ALBERT

Description: ‘Basic research’ is based on epistemological and intentional criteria. In terms of science policy, however, these criteria imply contradictory views on investment in ‘basic research’. The former espouses the linear model of innovation and encourages policy-makers concerned with economic problems to expand investment on basic research. However, the latter can collide with the policy norm of policy-makers and discourage investment in ‘basic research’ in an institutional setting where the nation-state prevails over scientists, as in South Korea. Emphasizing policy ideas and policy learning, this paper empirically shows that changes in investment priority and the emergence of new concepts about ‘basic research’ are co-products of a policy paradigm of the linear model and a policy norm of industrial competitiveness in Korea. Specifically, emphasis was placed on the balance between pure and oriented basic research, but moved on to ‘oriented basic research’, ‘basic engineering’, and to ‘basic research’ coupled with ‘woncheon-technology’.

Description: Contending that collaboration management practices and interpersonal relationships are the main factors in successful collaboration in R&D, scholars have turned their attention to the relationships between collaborators. Internal factors in research collaboration activities are not yet understood at the team level. They are the so-called black box of collaboration study. The purpose of this paper is to empirically demonstrate how factors relating to team characteristics, motivation, and processes influence research impact. The study works from a multi-theoretical perspective, extending from behavioral science to general management study, and seeks to answer the question: How should we organize and manage a collaborative team to improve its research impact? The empirical results show that, along with previously identified qualitative and quantitative factors, input factors such as: project motivation, transformational leadership, frequent face-to-face communication, more outsourcing, more attentional resource, and more evenly distributed workload improve research impact.

Description: Parents influence their children's eating behavior by providing access to certain types of food, creating enjoyable mealtimes and associations with food, and by role modeling. In this study we investigate the association between parental employment and parental time spent eating with their children. Using data from the 2001/02 German Time Budget Survey, we explore associations between time spent eating with children and labor force participation in Germany. We find that parental labor force participation is negatively associated with time spent eating with children. Each additional hour of work per day by the mother is associated with a 2.4 minute decrease in the amount of time the mother spends eating with her children. For paternal hours of work, we find that the more time a father spends working, the less time the child spends eating with the father or with both parents. Overall, we find evidence of mother inter-gender time substitution and some amount of time/food away from home substitution. Understanding how parents allocate their time, where they are most likely to eat, and what drives these decisions is an important endeavor since parents play a critical role in shaping and reinforcing their children's eating practices.

Description: While many governments subsidize extension programs, financial incentives for participation in extension programs are rare and little is known about such initiatives. This article assesses whether a financial incentive for an agricultural extension program for dairy farmers in Ireland has an impact on the type of farmer that participates in extension services. The findings reveal that financial incentives encourage participation, especially with cohorts of farmers that previously eschewed such programs. Several aspects of the overall economic effectiveness of the extension program are discussed and policy recommendations are outlined.

Description: Using a mathematical programming model of Norwegian agriculture, we explore interconnections between trade liberalization and reductions in greenhouse gas (GHG) emissions. We show that the Doha Round proposals for a new agreement on agriculture through the World Trade Organization would not generate significant reductions in emissions. Further trade liberalization would reduce emissions by cutting agricultural production but would not change production methods. Imposing a carbon tax would lead both to a reduction in output and the extensification of production. In contrast, if farmers are allowed to claim a credit for carbon sequestration the effect is to intensify agricultural production.

Description: The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) Program is a key part of America's safety net, but its structure fails to incentivize participants to be cost-conscious in their purchases and may cause retailers to attach excessive markups to WIC products. We investigate cost containment in the WIC Program, with a focus on California. Results show that smaller vendors often charge considerably higher prices for WIC foods than their larger counterparts. However, larger vendors do not mark up WIC foods more or promote them less than comparable control products. Cost containment can be improved by targeting WIC Program sales to larger vendors when it is possible to do so without compromising participant access, and using large-vendor prices as a benchmark to limit prices set by smaller vendors.

Description: Policy makers in the United States often justify agricultural subsidies by stressing that agriculture is the engine of the rural economy. We use the increase in crop prices in the late 2000s to estimate the marginal effect of increased agricultural revenues on local economies in the U.S. Heartland. We find that $1 more in crop revenue generated 64¢ in personal income, with most going to farm proprietors and workers (59%) or nonfarmers who own farm assets (36%). The evidence suggests a weak link between revenues and nonfarm income or employment, or on population. Cuts to agricultural subsidies are therefore likely to have little effect on the broader rural economy in regions like the Heartland.

Description: Farmers throughout the developing world face multiple sources of uninsured risk to agricultural production and household assets. In this paper, we present results from an experimental demand-elicitation exercise in rural Bangladesh to shed light on smallholder farmers' interest in formal insurance products. We propose a suite of insurance and savings products, and we randomly vary the price of one insurance option (area-yield insurance) and the presence of one of the savings options (group savings). Consistent with economic theory, farmers buy more of the insurance products that cover the risks they primarily face. However, because farmers are subject to a variety of risks, they do not focus on only one type of insurance; instead, they evenly split their endowment between life and disability insurance and agricultural insurance. Demand for area-yield insurance falls with price; we also observe important cross-price elasticities with other insurance products. The presence of group savings does not alter demand for insurance, though group savings is found to be a particularly popular risk management tool, especially when decisions are made in groups.

Description: We demonstrate the real-time observation of phonon-polariton propagation in ferroelectric LiNbO 3 using a single-shot spectroscopic setup that employs an echelon mirror. The echelon mirror provides a spatially encoded time delay for the probe pulse; therefore, the ultrafast transient behavior of materials can be detected on a single-shot basis. Using optical Kerr gate apparatus, forward and backward propagating E -mode phonon-polaritons were simultaneously induced via an impulsive stimulated Raman scattering process, and subsequently, their dynamics were readily mapped in time-frequency space using heterodyne detection. The two phonon-polaritons appeared on opposite sides of the central probe wavelength and were symmetrically imaged against the ordinary and extraordinary probe lights. By taking into account coupling of the lowest E -mode phonon-polariton to a low-frequency relaxational mode, not only the phonon-polariton dispersion but also the wavevector dependence of the damping rate was unveiled and quantitatively evaluated.

Description: This is the report on trap states in enhancement-mode AlGaN/GaN/AlGaN double heterostructures high electron mobility transistors by fluorine plasma treatment with different GaN channel layer thicknesses. Compared with the thick GaN channel layer sample, the thin one has smaller 2DEG concentration, lower electron mobility, lower saturation current, and lower peak transconductance, but it has a higher threshold voltage of 1.2 V. Deep level transient spectroscopy measurements are used to obtain the accurate capture cross section of trap states. By frequency dependent capacitance and conductance measurements, the trap state density of (1.98–2.56) × 10 12  cm −2 eV −1 is located at E T in a range of (0.37–0.44) eV in the thin sample, while the trap state density of (2.3–2.92) × 10 12  cm −2 eV −1 is located at E T in a range of (0.33–0.38) eV in the thick one. It indicates that the trap states in the thin sample are deeper than those in the thick one.

Description: Source attribution and process analysis for atmospheric mercury in eastern China simulated by CMAQ-Hg Atmospheric Chemistry and Physics, 15, 8767-8779, 2015 Author(s): J. Zhu, T. Wang, J. Bieser, and V. Matthias The contribution from different emission sources and atmospheric processes to gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), particulate bound mercury (PBM) and mercury deposition in eastern China were quantified using the Community Multi-scale Air Quality (CMAQ-Hg) modeling system run with a nested domain. Natural sources (NAT) and six categories of anthropogenic mercury sources (ANTH) including cement production (CEM), domestic life (DOM), industrial boilers (IND), metal production (MET), coal-fired power plants (PP) and traffic (TRA) were considered for source apportionment. NAT were responsible for 36.6 % of annual averaged GEM concentration, which was regarded as the most important source for GEM in spite of obvious seasonal variation. Among ANTH, the influence of MET and PP on GEM were most evident especially in winter. ANTH dominated the variations of GOM and PBM concentrations with contributions of 86.7 and 79.1 %, respectively. Among ANTH, IND were the largest contributor for GOM (57.5 %) and PBM (34.4 %) so that most mercury deposition came from IND. The effect of mercury emitted from out of China was indicated by a 〉 30 % contribution to GEM concentration and wet deposition. The contributions from nine processes – consisting of emissions (EMIS), gas-phase chemical production/loss (CHEM), horizontal advection (HADV), vertical advection (ZADV), horizontal advection (HDIF), vertical diffusion (VDIF), dry deposition (DDEP), cloud processes (CLDS) and aerosol processes (AERO) – were calculated for process analysis with their comparison in urban and non-urban regions of the Yangtze River delta (YRD). EMIS and VDIF affected surface GEM and PBM concentrations most and tended to compensate each other all the time in both urban and non-urban areas. However, DDEP was the most important removal process for GOM with 7.3 and 2.9 ng m −3 reduced in the surface of urban and non-urban areas, respectively, in 1 day. The diurnal profile variation of processes revealed the transportation of GOM from urban area to non-urban areas and the importance of CHEM/AERO in higher altitudes which partly caused diffusion of GOM downwards to non-urban areas. Most of the anthropogenic mercury was transported and diffused away from urban areas by HADV and VDIF and increased mercury concentrations in non-urban areas by HADV. Natural emissions only influenced CHEM and AERO more significantly than anthropogenic. Local emissions in the YRD contributed 8.5 % more to GEM and ~ 30 % more to GOM and PBM in urban areas compared to non-urban areas.

Description: Seasonal variation of secondary organic aerosol tracers in Central Tibetan Plateau Atmospheric Chemistry and Physics, 15, 8781-8793, 2015 Author(s): R.-Q. Shen, X. Ding, Q.-F. He, Z.-Y. Cong, Q.-Q. Yu, and X.-M. Wang Secondary organic aerosol (SOA) affects the earth's radiation balance and global climate. High-elevation areas are sensitive to global climate change. However, at present, SOA origins and seasonal variations are understudied in remote high-elevation areas. In this study, particulate samples were collected from July 2012 to July 2013 at the remote Nam Co (NC) site, Central Tibetan Plateau and analyzed for SOA tracers from biogenic (isoprene, monoterpenes and β-caryophyllene) and anthropogenic (aromatics) precursors. Among these compounds, isoprene SOA (SOA I ) tracers represented the majority (26.6 ± 44.2 ng m −3 ), followed by monoterpene SOA (SOA M ) tracers (0.97 ± 0.57 ng m −3 ), aromatic SOA (SOA A ) tracer (2,3-dihydroxy-4-oxopentanoic acid, DHOPA, 0.25 ± 0.18 ng m −3 ) and β-caryophyllene SOA tracer (β-caryophyllenic acid, 0.09 ± 0.10 ng m −3 ). SOA I tracers exhibited high concentrations in the summer and low levels in the winter. The similar temperature dependence of SOA I tracers and isoprene emission suggested that the seasonal variation of SOA I tracers at the NC site was mainly influenced by the isoprene emission. The ratio of high-NO x to low-NO x products of SOA I (2-methylglyceric acid to 2-methyltetrols) was highest in the winter and lowest in the summer, due to the influence of temperature and relative humidity. The seasonal variation of SOA M tracers was impacted by monoterpenes emission and gas-particle partitioning. During the summer to the fall, temperature effect on partitioning was the dominant process influencing SOA M tracers' variation; while the temperature effect on emission was the dominant process influencing SOA M tracers' variation during the winter to the spring. SOA M tracer levels did not elevate with increased temperature in the summer, probably resulting from the counteraction of temperature effects on emission and partitioning. The concentrations of DHOPA were 1–2 orders of magnitude lower than those reported in the urban regions of the world. Due to the transport of air pollutants from the adjacent Bangladesh and northeastern India, DHOPA presented relatively higher levels in the summer. In the winter when air masses mainly came from northwestern India, mass fractions of DHOPA in total tracers increased, although its concentrations declined. The SOA-tracer method was applied to estimate secondary organic carbon (SOC) from these four precursors. The annual average of SOC was 0.22 ± 0.29 μgC m −3 , with the biogenic SOC (sum of isoprene, monoterpenes and β-caryophyllene) accounting for 75 %. In the summer, isoprene was the major precursor with its SOC contributions of 81 %. In the winter when the emission of biogenic precursors largely dropped, the contributions of aromatic SOC increased. Our study implies that anthropogenic pollutants emitted in the Indian subcontinent could be transported to the TP and have an impact on SOC over the remote NC.

Description: Influence of biomass burning on CCN number and hygroscopicity during summertime in the eastern Mediterranean Atmospheric Chemistry and Physics Discussions, 15, 21539-21582, 2015 Author(s): A. Bougiatioti, S. Bezantakos, I. Stavroulas, N. Kalivitis, P. Kokkalis, G. Biskos, N. Mihalopoulos, A. Papayannis, and A. Nenes This study investigates the CCN activity and hygroscopic properties of particles influenced by biomass burning in the eastern Mediterranean. Air masses sampled were subject to a range of atmospheric processing (several hours up to 3 days). Values of the hygroscopicity parameter, κ, were derived from cloud condensation nuclei (CCN) measurements and a Hygroscopic Tandem Differential Mobility Analyzer (HTDMA). An Aerosol Chemical Speciation Monitor (ACSM) was also used to determine the chemical composition and mass concentration of non-refractory components of the submicron aerosol fraction. During fire events, the increased organic content (and lower inorganic fraction) of the aerosol decreases the hygroscopicity parameter, κ, for all particle sizes. The reason, however, for this decrease was not the same for all size modes; smaller particle sizes appeared to be richer in less hygroscopic, less CCN-active components due to coagulation processes while larger particles become less hygroscopic during the biomass burning events due to condensation of less hygroscopic gaseous compounds. In addition, smaller particles exhibited considerable chemical dispersion (where hygroscopicity varied up to 100 % for particles of same size); larger particles, however, exhibited considerably less dispersion owing to the effects of aging and retained high levels of CCN activity. These conclusions are further supported by the observed mixing state determined by the HTDMA measurements. ACSM measurements indicate that the bulk composition reflects the hygroscopicity and chemical nature of the largest particles and a large fraction of the CCN concentrations sampled. Based on Positive Matrix Factorization (PMF) analysis of the organic ACSM spectra, CCN concentrations follow a similar trend with the BBOA component, with enhancements of CCN in biomass burning plumes ranging between 65 and 150 %, for supersaturations ranging between 0.2 and 0.7 %. Using multilinear regression, we determine the hygroscopicity of the prime organic aerosol components (BBOA, OOA-BB and OOA); it is found that the total organic hygroscopicity is very close to the inferred hygroscopicity of the oxygenated organic aerosol components. Finally, the transformation of freshly-emitted biomass burning (BBOA) to more oxidized organic aerosol (OOA-BB) can result in a two-fold increase of the inferred organic hygroscopicity. Almost 10 % of the total aerosol hygroscopicity is related to the two biomass burning components (BBOA and OOA-BB), which in turn contribute almost 35 % to the fine-particle organic water of the aerosol. This is important as organic water can contribute to the atmospheric chemistry and the direct radiative forcing.

Description: Measurement-based direct radiative effect by brown carbon over Indo-Gangetic Plain Atmospheric Chemistry and Physics Discussions, 15, 21583-21606, 2015 Author(s): A. Arola, G. L. Schuster, M. R. A. Pitkänen, O. Dubovik, H. Kokkola, A. V. Lindfors, T. Mielonen, T. Raatikainen, S. Romakkaniemi, S. N. Tripathi, and H. Lihavainen The importance of light absorbing organic aerosols, often called brown carbon (BrC), has become evident in recent years. However, there are relatively few measurement-based estimates for the direct radiative effect of BrC so far. In those earlier studies, the AErosol RObotic NETwork (AERONET) measured Aerosol Absorption Optical Depth (AAOD) and Absorption Angstrom Exponent (AAE) have been exploited. However, these two pieces of information are clearly not sufficient to separate properly carbonaceous aerosols from dust, while imaginary indices of refraction would contain more and better justified information for this purpose. This is first time that the direct radiative effect (DRE) of BrC is estimated by exploiting the AERONET-retrieved imaginary indices. We estimated it for four sites in Indo-Gangetic Plain (IGP), Karachi, Lahore, Kanpur and Gandhi College. We found a distinct seasonality, which was generally similar among all the sites, but with slightly different strengths. The monthly warming effect up to 0.5 W m -2 takes place during spring season. On the other hand, BrC results in overall cooling effect in the winter season, which can reach levels close to −1W m -2 . We then estimated similarly also DRE of black carbon and total aerosol, in order to assess the relative significance of BrC radiative effect in the radiative effects of other components. Even though BrC impact seems minor in this context, we demonstrated that it is not insignificant and moreover that it is crucial to perform spectrally resolved radiative transfer calculations to obtain good estimates for DRE of BrC.

Description: Contrail life cycle and properties from 1 year of MSG/SEVIRI rapid-scan images Atmospheric Chemistry and Physics, 15, 8739-8749, 2015 Author(s): M. Vázquez-Navarro, H. Mannstein, and S. Kox The automatic contrail tracking algorithm (ACTA) – developed to automatically follow contrails as they age, drift and spread – enables the study of a large number of contrails and the evolution of contrail properties with time. In this paper we present a year's worth of tracked contrails, from August 2008 to July 2009 in order to derive statistically significant mean values. The tracking is performed using the 5 min rapid-scan mode of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat Second Generation (MSG) satellites. The detection is based on the high spatial resolution of the images provided by the Moderate Resolution Imaging Spectroradiometer on board the Terra satellite (Terra/MODIS), where a contrail detection algorithm (CDA) is applied. The results show the satellite-derived average lifetimes of contrails and contrail-cirrus along with the probability density function (PDF) of other geometric characteristics such as mean coverage, distribution and width. In combination with specifically developed algorithms (RRUMS; Rapid Retrieval of Upwelling irradiance from MSG/SEVIRI and COCS (Cirrus Optical properties derived from CALIOP and SEVIRI), explained below) it is possible to derive the radiative forcing (RF), energy forcing (EF), optical thickness (τ) and altitude of the tracked contrails. Mean values here retrieved are duration, 1 h; length, 130 km; width, 8 km; altitude, 11.7 km; optical thickness, 0.34. Radiative forcing and energy forcing are shown for land/water backgrounds in day/night situations.

Description: Accounting for the effects of sastrugi in the CERES clear-sky Antarctic shortwave angular distribution models Atmospheric Measurement Techniques, 8, 3163-3175, 2015 Author(s): J. Corbett and W. Su The Cloud and the Earth's Radiant Energy System (CERES) instruments on NASA's Terra, Aqua and Soumi NPP satellites are used to provide a long-term measurement of Earth's energy budget. To accomplish this, the radiances measured by the instruments must be inverted to fluxes by the use of a scene-type-dependent angular distribution model (ADM). For permanent snow scenes over Antarctica, shortwave (SW) ADMs are created by compositing radiance measurements over the full viewing zenith and azimuth range. However, the presence of small-scale wind blown roughness features called sastrugi cause the BRDF (bidirectional reflectance distribution function) of the snow to vary significantly based upon the solar azimuth angle and location. This can result in monthly regional biases between −12 and 7.5 Wm −2 in the inverted TOA (top-of-atmosphere) SW flux. The bias is assessed by comparing the CERES shortwave fluxes derived from nadir observations with those from all viewing zenith angles, as the sastrugi affect fluxes inverted from the oblique viewing angles more than for the nadir viewing angles. In this paper we further describe the clear-sky Antarctic ADMs from Su et al. (2015). These ADMs account for the sastrugi effect by using measurements from the Multi-Angle Imaging Spectro-Radiometer (MISR) instrument to derive statistical relationships between radiance from different viewing angles. We show here that these ADMs reduce the bias and artifacts in the CERES SW flux caused by sastrugi, both locally and Antarctic-wide. The regional monthly biases from sastrugi are reduced to between −5 and 7 Wm −2 , and the monthly-mean biases over Antarctica are reduced by up to 0.64 Wm −2 , a decrease of 74 %. These improved ADMs are used as part of the Edition 4 CERES SSF (Single Scanner Footprint) data.

Description: Space-borne observation of methane from atmospheric infrared sounder version 6: validation and implications for data analysis Atmospheric Measurement Techniques Discussions, 8, 8563-8597, 2015 Author(s): X. Xiong, F. Weng, Q. Liu, and E. Olsen Atmospheric Methane (CH 4 ) is generated as a standard product in recent version of the hyperspectral Atmospheric Infrared Sounder (AIRS-V6) aboard NASA's Aqua satellite at the NASA Goddard Earth Sciences Data and Information Services Center (NASA/GES/DISC). Significant improvements in AIRS-V6 was expected but without a thorough validation. This paper first introduced the improvements of CH 4 retrieval in AIRS-V6 and some characterizations, then presented the results of validation using ~ 1000 aircraft profiles from several campaigns spread over a couple of years and in different regions. It was found the mean biases of AIRS CH 4 at layers 343–441 and 441–575 hPa are −0.76 and −0.05 % and the RMS errors are 1.56 and 1.16 %, respectively. Further analysis demonstrates that the errors in the spring and in the high northern latitudes are larger than in other seasons or regions. The error is correlated with Degree of Freedoms (DOFs), particularly in the tropics or in the summer, and cloud amount, suggesting that the "observed" spatiotemporal variation of CH 4 by AIRS is imbedded with some artificial impact from the retrieval sensitivity in addition to its variation in reality, so the variation of information content in the retrievals needs to be taken into account in data analysis of the retrieval products. Some additional filtering (i.e. rejection of profiles with obvious oscillation as well as those deviating greatly from the norm) for quality control is recommended for the users to better utilize AIRS-V6 CH 4 , and their implementation in the future versions of the AIRS retrieval algorithm is under consideration.

Description: Impact of aerosols on the OMI tropospheric NO 2 retrievals over industrialized regions: how accurate is the aerosol correction of cloud-free scenes via a simple cloud model? Atmospheric Measurement Techniques Discussions, 8, 8385-8437, 2015 Author(s): J. Chimot, T. Vlemmix, J. P. Veefkind, J. F. de Haan, and P. F. Levelt The Ozone Monitoring Instrument (OMI) instrument has provided daily global measurements of tropospheric NO 2 for more than a decade. Numerous studies have drawn attention to the complexities related to measurements of tropospheric NO 2 in the presence of aerosols. Fine particles affect the OMI spectral measurements and the length of the average light path followed by the photons. However, they are not explicitly taken into account in the current OMI tropospheric NO 2 retrieval chain. Instead, the operational OMI O 2 -O 2 cloud retrieval algorithm is applied both to cloudy scenes and to cloud free scenes with aerosols present. This paper describes in detail the complex interplay between the spectral effects of aerosols, the OMI O 2 -O 2 cloud retrieval algorithm and the impact on the accuracy of the tropospheric NO 2 retrievals through the computed Air Mass Factor (AMF) over cloud-free scenes. Collocated OMI NO 2 and MODIS Aqua aerosol products are analysed over East China, in industrialized area. In addition, aerosol effects on the tropospheric NO 2 AMF and the retrieval of OMI cloud parameters are simulated. Both the observation-based and the simulation-based approach demonstrate that the retrieved cloud fraction linearly increases with increasing Aerosol Optical Thickness (AOT), but the magnitude of this increase depends on the aerosol properties and surface albedo. This increase is induced by the additional scattering effects of aerosols which enhance the scene brightness. The decreasing effective cloud pressure with increasing AOT represents primarily the absorbing effects of aerosols. The study cases show that the actual aerosol correction based on the implemented OMI cloud model results in biases between −20 and −40 % for the DOMINO tropospheric NO 2 product in cases of high aerosol pollution (AOT ≥ 0.6) and elevated particles. On the contrary, when aerosols are relatively close to the surface or mixed with NO 2 , aerosol correction based on the cloud model results in overestimation of the DOMINO tropospheric NO 2 product, between 10 and 20 %. These numbers are in line with comparison studies between ground-based and OMI tropospheric NO 2 measurements under conditions with high aerosol pollution and elevated particles. This highlights the need to implement an improved aerosol correction in the computation of tropospheric NO 2 AMFs.

Description: Sensitivity of thermal infrared sounders to the chemical and micro-physical properties of UTLS secondary sulphate aerosols Atmospheric Measurement Techniques Discussions, 8, 8439-8481, 2015 Author(s): P. Sellitto and B. Legras Monitoring upper tropospheric-lower stratospheric (UTLS) secondary sulphate aerosols and their chemical and micro-physical properties from satellite nadir observations is crucial to better understand their formation and evolution processes and then to estimate their impact to the UTLS chemistry, and on regional and global radiative balance. Here we present a study aimed at the evaluation of the sensitivity of thermal infrared (TIR) satellite nadir observations to the chemical composition and the size distribution of idealized UTLS sulphate aerosol layers. The extinction properties of sulphuric acid/water droplets, for different sulphuric acid mixing ratios and temperatures, are systematically analysed. The extinction coefficients are derived by means of a Mie code, using refractive indexes taken from the GEISA (Gestion et Étude des Informations Spectroscopiques Atmosphériques: Management and Study of Spectroscopic Information) spectroscopic database and log-normal size distributions with different effective radii and number concentrations. IASI (Infrared Atmospheric Sounding Interferometer) pseudo-observations are generated using forward radiative transfer calculations performed with the 4A (Automatized Atmospheric Absorption Atlas) radiative transfer model, to estimate the impact of the extinction of idealized aerosol layers, at typical UTLS conditions, on the brightness temperature spectra observed by this satellite instrument. We found a marked and typical spectral signature of these aerosol layers between 700 and 1200 cm −1 , due to the absorption bands of the sulphate and bi-sulphate ions and the undissociated sulphuric acid, with the main absorption peaks at 1170 and 905 cm −1 . The dependence of the aerosol spectral signature to the sulphuric acid mixing ratio, and effective number concentration and radius, as well as the role of interferring parameters like the ozone, sulphur dioxide, carbon dioxide and ash absorption, and temperature and water vapour profile uncertainties, are analyzed and critically discussed.

Description: Global cloud top height retrieval using SCIAMACHY limb spectra: model studies and first results Atmospheric Measurement Techniques Discussions, 8, 8295-8352, 2015 Author(s): K.-U. Eichmann, L. Lelli, C. von Savigny, H. Sembhi, and J. P. Burrows Cloud top heights (CTH) were retrieved for the period 1 January 2003 to 7 April 2012 using height-resolved limb spectra measured with the Scanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) on board ENVISAT (ENVIronmental SATellite). In this study, we tested the sensitivity of the colour index method used in the retrieval code SCODA (SCIAMACHY Cloud Detection Algorithm) and the accuracy of the retrieved CTHs in comparison to other methods. Sensitivity studies using the radiative transfer model SCIATRAN showed that the method is capable of generally detecting cloud tops down to about 5 km and very thin cirrus clouds even up to the tropopause. Volcanic particles can also be detected that occasionally reach the lower stratosphere. Low clouds at 2–3 km can only be retrieved under very clean atmospheric conditions, as light scattering of aerosols interferes with the cloud retrieval. Upper tropospheric ice clouds are detectable for cloud optical depths down to about τ N = 0.005, which is in the subvisual range. The detection sensitivity decreases towards the surface. An optical thickness of roughly 0.1 was the lower detection limit for water cloud top heights at 5 km. This value is much lower than thresholds reported for the passive cloud detection in nadir viewing direction. Comparisons with SCIAMACHY nadir cloud top heights, calculated with the Semi-Analytical CloUd Retrieval Algorithm (SACURA), showed a good agreement in the global cloud field distribution. But only opaque clouds (τ N 〉 5) are detectable with the nadir passive retrieval technique in the UV-visible and infrared wavelength range. So due to the frequent occurrence of thin and sub-visual cirrus clouds in the tropics, large cloud top height deviations were detected between both viewing geometries. Also the land/sea contrast seen in nadir retrievals was not detected in limb mode. Co-located cloud top height measurements of the limb viewing Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on ENVISAT for the period from January 2008 to March 2012 were compared, showing good agreement to within 1 km, which is smaller than the vertical field of view of both instruments. Lower stratospheric aerosols from volcanic eruptions occasionally interfered with the cloud retrieval and inhibited detection of tropospheric clouds. Examples of the impact of these events are shown for the volcanoes Kasatochi in August 2008, Sarychev Peak in June 2009, and Nabro in June 2010. Long-lasting aerosol layers were detected after these events in the Northern Hemisphere down to the tropics. Particle top heights up to about 22 km were retrieved in 2009, when the enhanced lower stratospheric aerosol layer persisted for about 7 months. Up to about 82 % of the Northern hemispheric lower stratosphere between 30° and 70° was covered by scattering particles in August 2009 and nearly half in October 2008.

Description: Operation of the Airmodus A11 nano Condensation Nucleus Counter at various inlet pressures, various operation temperatures and design of a new inlet system Atmospheric Measurement Techniques Discussions, 8, 8483-8508, 2015 Author(s): J. Kangasluoma, A. Franchin, J. Duplissy, L. Ahonen, F. Korhonen, M. Attoui, J. Mikkilä, K. Lehtipalo, J. Vanhanen, M. Kulmala, and T. Petäjä Measuring sub-3 nm particles outside of controlled laboratory conditions is a challenging task, as many of the instruments are operated at their limits and are subjected to changing ambient conditions. In this study, we advance the current understanding on the operation of Airmodus A11 nano Condensation Nucleus Counter (nCNC), which consists of a A10 Particle Size Magnifier (PSM) and A20 condensation particle counter (CPC). We explore the effect of the inlet line pressure on the measured particle concentration. We identify two different regions inside the instrument where supersaturation of working fluid can take place. We show the possibility of varying the cut-off of the instrument from 1 to 6 nm, a wider size range than the one usually covered by the PSM. We also present a new inlet system, which allows automated measurements of the background, minimizes the diffusion losses in the sampling line and is equipped with an electrostatic filter to remove ions. Finally, our view of the guidelines for optimal use of the Airmodus nCNC are provided.

Description: Looking beyond stratification: a model-based analysis of the biological drivers of oxygen depletion in the North Sea Biogeosciences Discussions, 12, 12543-12610, 2015 Author(s): F. Große, N. Greenwood, M. Kreus, H. J. Lenhart, D. Machoczek, J. Pätsch, L. A. Salt, and H. Thomas The problem of low oxygen conditions, often referred to as hypoxia, occurs regularly in the North Sea, a temperate European shelf sea. Stratification represents a major process regulating the seasonal dynamics of bottom oxygen. However, lowest oxygen conditions in the North Sea do not occur in the regions of strongest stratification. This suggests that stratification is an important prerequisite for hypoxia, but that the complex interaction between hydrodynamics and the biological processes drives its development. In this study we use the ecosystem model HAMSOM-ECOHAM5 to provide a general characteristic of the different North Sea oxygen regimes, and to quantify the impact of the different physical and biological factors driving the oxygen dynamics below the thermocline and in the bottom layer. We show that the North Sea can be subdivided into three different regimes in terms of oxygen dynamics: (1) a highly productive, non-stratified coastal regime, (2) a productive, seasonally stratified regime with a small sub-thermocline volume, and (3) a productive, seasonally stratified regime with a large sub-thermocline volume, with regime 2 being highly susceptible to hypoxic conditions. Our analysis of the different processes driving the oxygen development reveals that inter-annual variations in the oxygen conditions are caused by variations in primary production, while spatial differences can be attributed to differences in stratification and water depth. In addition, we show that benthic bacteria represent the main oxygen consumers in the bottom layer, consistently accounting for more than 50 % of the overall consumption. By providing these valuable insights, we show that ecosystem models can be a useful tool for the interpretation of observations and the estimation of the impact of anthropogenic drivers on the North Sea oxygen conditions.

Description: Impact of the oceanic geothermal heat flux on a glacial ocean state Climate of the Past Discussions, 11, 3597-3624, 2015 Author(s): M. Ballarotta, F. Roquet, S. Falahat, Q. Zhang, and G. Madec The oceanic geothermal heating (OGH) has a significant impact on the present-day ocean state, but its role during glacial periods, when the ocean circulation and stratification were different from those of today, remains poorly known. In the present study, we analyzed the response of the glacial ocean to OGH, by comparing ocean simulations of the Last Glacial Maximum (LGM, ∼ 21 ka ago) including or not geothermal heating. We found that applying the OGH warmed the Antarctic Bottom Waters (AABW) by ∼ 0.4 °C and increased the abyssal circulation by 15 to 30 % north of 30° S in the deep Pacific and Atlantic basins. The geothermally heated deep waters were then advected toward the Southern Ocean where they upwelled to the surface due to the Ekman transport. The extra heat transport towards Antarctica acted to reduce the amount of sea ice contributing to the freshening of the whole AABW overturning cell. The global amount of salt being conserved, this bottom freshening induced a salinification of the North Atlantic and North Pacific surface and intermediate waters, contributing to the deepening of the North Atlantic Deep Water. This indirect mechanism is responsible for the largest observed warming, found in the North Atlantic deep western boundary current between 2000 and 3000 m (up to 2 °C). The characteristic time scale of the ocean response to the OGH corresponds to an advective time scale (associated with the overturning of the AABW cell) rather than a diffusive time scale. The OGH might facilitate the transition from a glacial to an inter-glacial state but its effect on the deep stratification seems insufficient to drive alone an abrupt climate change.

Description: Woodland Survey of Great Britain 1971–2001 Earth System Science Data, 7, 203-214, 2015 Author(s): C. M. Wood, S. M. Smart, and R. G. H. Bunce The Woodland Survey of Great Britain is a unique data set, consisting of a detailed range of ecological measurements at a national scale, covering a time span of 30 years. A set of 103 woods spread across Britain were first surveyed in 1971, which were again surveyed in 2000–2003 (for convenience referred to subsequently as the "2001 survey"). Standardised methods of describing the trees, shrubs, ground flora, soils and general habitats present were used for both sets of surveys. The sample of 1648 plots spread through 103 woodland sites located across Britain makes it probably the most extensive quantitative ecological woodland survey undertaken in Britain; it is also notable for the range of sites that have been revisited after such a long interval. The data set provides a unique opportunity to explore the effects of a range of potential drivers of woodland change that operated between 1971 and 2001. The data set is available in four discrete parts, which have been assigned the following DOIs: doi:10.5285/4d93f9ac-68e3-49cf-8a41-4d02a7ead81a (Kirby et al., 2013b), doi:10.5285/d6409d40-58fe-4fa7-b7c8-71a105b965b4 (Kirby et al., 2013d), doi:10.5285/fb1e474d-456b-42a9-9a10-a02c35af10d2 (Kirby et al., 2013c), doi:10.5285/2d023ce9-6dbe-4b4f-a0cd-34768e1455ae (Kirby et al., 2013a).

Description: Estimating greenhouse gas emissions from travel – a GIS-based study Geographica Helvetica, 70, 185-192, 2015 Author(s): S. Kuonen Conferences, meetings and congresses are an important part of today's economic and scientific world. But the environmental impact, especially from greenhouse gas emissions associated with travel, can be extensive. Anthropogenic greenhouse gas (GHG) emissions account for the warming of the atmosphere and oceans. This study draws on the need to quantify and reduce greenhouse gas emissions associated with travel activities and aims to give suggestions for organizers and participants on possible ways to reduce greenhouse gas emissions, demonstrated on the example of the European Geography Association (EGEA) Annual Congress 2013 in Wasilkow, Poland. The lack of a comprehensive methodology for the estimation of greenhouse gas emissions from travel led to an outline of a methodology that uses geographic information systems (GIS) to calculate travel distances. The calculation of travel distances in GIS is adapted from actual transportation infrastructure, derived from the open-source platform OpenStreetMap. The methodology also aims to assess the possibilities to reduce GHG emissions by choosing different means of transportation and a more central conference location. The results of the participants of the EGEA congress, who shared their travel data for this study, show that the total travel distance adds up to 238 000 km, with average travel distance of 2429 km per participant. The travel activities of the participants in the study result in total GHG emissions of 39 300 kg CO 2 -eq including both outward and return trip. On average a participant caused GHG emissions of 401 kg CO 2 -eq. In addition, the analysis of the travel data showed differences in travel behaviour depending on the distance between conference site and point of origin. The findings on travel behaviour have then been used to give an estimation of total greenhouse gas emissions from travel for all participants of the conference, which result in a total amount of 79 711 kg CO 2 -eq. The potential for reducing greenhouse gas emissions by substituting short flights with train rides and car rides with bus and train rides is limited. Only 6 % of greenhouse gas emissions could be saved by applying these measures. Further considerable savings could only be made by substituting longer flights (32.6 %) or choosing a more central conference location (26.3 %).

Description: Singular vector based targeted observations of chemical constituents: description and first application of the EURAD-IM-SVA Geoscientific Model Development Discussions, 8, 6267-6307, 2015 Author(s): N. Goris and H. Elbern Measurements of the large dimensional chemical state of the atmosphere provide only sparse snapshots of the state of the system due to their typically insufficient temporal and spatial density. In order to optimize the measurement configurations despite those limitations, the present work describes the identification of sensitive states of the chemical system as optimal target areas for adaptive observations. For this purpose, the technique of singular vector analysis (SVA), which has been proved effective for targeted observations in numerical weather predication, is implemented into the chemical transport model EURAD-IM (EURopean Air pollution and Dispersion – Inverse Model) yielding the EURAD-IM-SVA. Besides initial values, emissions are investigated as critical simulation controlling targeting variables. For both variants, singular vectors are applied to determine the optimal placement for observations and moreover to quantify which chemical compounds have to be observed with preference. Based on measurements of the airship based ZEPTER-2 campaign, the EURAD-IM-SVA has been evaluated by conducting a comprehensive set of model runs involving different initial states and simulation lengths. Since the considered cases are restricted in terms of considered chemical compounds and selected areas, they allow for a retracing of the results and a confirmation of their correctness. Our analysis shows that the optimal placement for observations of chemical species is not entirely determined by mere transport and mixing processes. Rather, a combination of initial chemical concentrations, chemical conversions, and meteorological processes determine the influence of chemical compounds and regions. We furthermore demonstrate that the optimal placement of observations of emission strengths is highly dependent on the location of emission sources and that the benefit of including emissions as target variables outperforms the value of initial value optimisation with growing simulation length. The obtained results confirm the benefit of considering both initial values and emission strengths as target variables and of applying the EURAD-IM-SVA for measurement decision guidance with respect to chemical compounds.

Description: A global scale mechanistic model of the photosynthetic capacity Geoscientific Model Development Discussions, 8, 6217-6266, 2015 Author(s): A. A. Ali, C. Xu, A. Rogers, R. A. Fisher, S. D. Wullschleger, N. G. McDowell, E. C. Massoud, J. A. Vrugt, J. D. Muss, J. B. Fisher, P. B. Reich, and C. J. Wilson Although plant photosynthetic capacity as determined by the maximum carboxylation rate (i.e., V c, max25 ) and the maximum electron transport rate (i.e., J max25 ) at a reference temperature (generally 25 °C) is known to vary substantially in space and time in response to environmental conditions, it is typically parameterized in Earth system models (ESMs) with tabulated values associated to plant functional types. In this study, we developed a mechanistic model of leaf utilization of nitrogen for assimilation (LUNA V1.0) to predict the photosynthetic capacity at the global scale under different environmental conditions, based on the optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The LUNA model was able to reasonably well capture the observed patterns of photosynthetic capacity in view that it explained approximately 55 % of the variation in observed V c, max25 and 65 % of the variation in observed J max25 across the globe. Our model simulations under current and future climate conditions indicated that V c, max25 could be most affected in high-latitude regions under a warming climate and that ESMs using a fixed V c, max25 or J max25 by plant functional types were likely to substantially overestimate future global photosynthesis.

Description: Uncertainties in calculating precipitation climatology in East Asia Hydrology and Earth System Sciences Discussions, 12, 7765-7783, 2015 Author(s): J. Kim and S. K. Park This study examines the uncertainty in calculating the fundamental climatological characteristics of precipitation in the East Asia region from multiple fine-resolution gridded analysis datasets based on in-situ rain gauge observations. Five observation-based gridded precipitation datasets are used to derive the long-term means, standard deviations in lieu of interannual variability and linear trends over the 28-year period from 1980 to 2007. Both the annual and summer (June–July–August) mean precipitation is examined. The agreement amongst these precipitation datasets are examined using multiple metrics including the signal-to-noise ratio (SNR) defined as the ratio between long-term means and the corresponding standard deviations, and Taylor diagrams which allows examinations of the pattern correlation, the standard deviation, and the centered root mean square error. It is found that the five gauge-based precipitation analysis datasets agree well in the long-term mean and interannual variability in most of the East Asia region including eastern China, Manchuria, South Korea, and Japan, which are densely populated and have fairly high density observation networks. The regions of large inter-dataset variations include Tibetan Plateau, Mongolia, northern Indo-China, and North Korea. The regions of large uncertainties are typically lightly populated and are characterized by severe terrain and/or extreme high elevations. Unlike the long-term mean and interannual variability, agreements between datasets in the linear trend is weak, both for the annual and summer mean values. In most of the East Asia region, the SNR for the linear trend is below 0.5, i.e., the inter-dataset variability exceeds the multi-data ensemble mean. The uncertainty in the spatial distribution of long-term means among these datasets occurs both in the spatial pattern and variability, but the uncertainty for the interannual variability and time trend is much larger in the variability than in the pattern correlation. Thus, care must be taken in using long-term trends calculated from gridded precipitation analysis data for climate studies over the East Asia region.

Description: Qualitative soil moisture assessment in semi-arid Africa – the role of experience and training on inter-rater reliability Hydrology and Earth System Sciences, 19, 3505-3516, 2015 Author(s): M. Rinderer, H. C. Komakech, D. Müller, G. L. B. Wiesenberg, and J. Seibert Soil and water management is particularly relevant in semi-arid regions to enhance agricultural productivity. During periods of water scarcity, soil moisture differences are important indicators of the soil water deficit and are traditionally used for allocating water resources among farmers of a village community. Here we present a simple, inexpensive soil wetness classification scheme based on qualitative indicators which one can see or touch on the soil surface. It incorporates the local farmers' knowledge on the best soil moisture conditions for seeding and brick making in the semi-arid environment of the study site near Arusha, Tanzania. The scheme was tested twice in 2014 with farmers, students and experts (April: 40 persons, June: 25 persons) for inter-rater reliability, bias of individuals and functional relation between qualitative and quantitative soil moisture values. During the test in April farmers assigned the same wetness class in 46 % of all cases, while students and experts agreed on about 60 % of all cases. Students who had been trained in how to apply the method gained higher inter-rater reliability than their colleagues with only a basic introduction. When repeating the test in June, participants were given improved instructions, organized in small subgroups, which resulted in a higher inter-rater reliability among farmers. In 66 % of all classifications, farmers assigned the same wetness class and the spread of class assignments was smaller. This study demonstrates that a wetness classification scheme based on qualitative indicators is a robust tool and can be applied successfully regardless of experience in crop growing and education level when an in-depth introduction and training is provided. The use of a simple and clear layout of the assessment form is important for reliable wetness class assignments.

Description: Nonlinear effects of locally heterogeneous hydraulic conductivity fields on regional stream–aquifer exchanges Hydrology and Earth System Sciences Discussions, 12, 7727-7764, 2015 Author(s): J. Zhu, C. L. Winter, and Z. Wang Computational experiments are performed to evaluate the effects of locally heterogeneous conductivity fields on regional exchanges of water between stream and aquifer systems in the Middle Heihe River Basin (MHRB) of northwestern China. The effects are found to be nonlinear in the sense that simulated discharges from aquifers to streams are systematically lower than discharges produced by a base model parameterized with relatively coarse effective conductivity. A similar, but weaker, effect is observed for stream leakage. The study is organized around three hypotheses: (H1) small-scale spatial variations of conductivity significantly affect regional exchanges of water between streams and aquifers in river basins, (H2) aggregating small-scale heterogeneities into regional effective parameters systematically biases estimates of stream–aquifer exchanges, and (H3) the biases result from slow-paths in groundwater flow that emerge due to small-scale heterogeneities. The hypotheses are evaluated by comparing stream–aquifer fluxes produced by the base model to fluxes simulated using realizations of the MHRB characterized by local (grid-scale) heterogeneity. Levels of local heterogeneity are manipulated as control variables by adjusting coefficients of variation. All models are implemented using the MODFLOW simulation environment, and the PEST tool is used to calibrate effective conductivities defined over 16 zones within the MHRB. The effective parameters are also used as expected values to develop log-normally distributed conductivity ( K ) fields on local grid scales. Stream-aquifer exchanges are simulated with K fields at both scales and then compared. Results show that the effects of small-scale heterogeneities significantly influence exchanges with simulations based on local-scale heterogeneities always producing discharges that are less than those produced by the base model. Although aquifer heterogeneities are uncorrelated at local scales, they appear to induce coherent slow-paths in groundwater fluxes that in turn reduce aquifer–stream exchanges. Since surface water–groundwater exchanges are critical hydrologic processes in basin-scale water budgets, these results also have implications for water resources management.

Description: Near–surface air temperature and snow skin temperature comparison from CREST-SAFE station data with MODIS land surface temperature data Hydrology and Earth System Sciences Discussions, 12, 7665-7687, 2015 Author(s): C. L. Pérez Díaz, T. Lakhankar, P. Romanov, J. Muñoz, R. Khanbilvardi, and Y. Yu Land Surface Temperature (LST) is a key variable (commonly studied to understand the hydrological cycle) that helps drive the energy balance and water exchange between the Earth's surface and its atmosphere. One observable constituent of much importance in the land surface water balance model is snow. Snow cover plays a critical role in the regional to global scale hydrological cycle because rain-on-snow with warm air temperatures accelerates rapid snow-melt, which is responsible for the majority of the spring floods. Accurate information on near-surface air temperature ( T -air) and snow skin temperature ( T -skin) helps us comprehend the energy and water balances in the Earth's hydrological cycle. T -skin is critical in estimating latent and sensible heat fluxes over snow covered areas because incoming and outgoing radiation fluxes from the snow mass and the air temperature above make it different from the average snowpack temperature. This study investigates the correlation between MODerate resolution Imaging Spectroradiometer (MODIS) LST data and observed T -air and T -skin data from NOAA-CREST-Snow Analysis and Field Experiment (CREST-SAFE) for the winters of 2013 and 2014. LST satellite validation is imperative because high-latitude regions are significantly affected by climate warming and there is a need to aid existing meteorological station networks with the spatially continuous measurements provided by satellites. Results indicate that near-surface air temperature correlates better than snow skin temperature with MODIS LST data. Additional findings show that there is a negative trend demonstrating that the air minus snow skin temperature difference is inversely proportional to cloud cover. To a lesser extent, it will be examined whether the surface properties at the site are representative for the LST properties within the instrument field of view.

Description: Does drought alter hydrological functions in forest soils? An infiltration experiment Hydrology and Earth System Sciences Discussions, 12, 7689-7725, 2015 Author(s): K. F. Gimbel, H. Puhlmann, and M. Weiler The water cycle is expected to change in future and severely affect precipitation patterns across central Europe and in other parts of the world, leading to more frequent and severe droughts. Usually, it is assumed that system properties, like soil properties, remain stable and will not be affected by drought events. To study if this assumption is appropriate, we address the effects of drought on the infiltration behavior of forest soils using dye tracer experiments on six sites in three regions across Germany, which were forced into drought conditions. The sites cover clayey, loamy and sandy textured soils. In each region, we compared a deciduous and a coniferous forest stand to address differences between the main tree species. The results of the dye tracer experiments show clear evidence for changes in infiltration behavior at the sites. The infiltration changed at the clayey plots from regular and homogeneous flow to fast preferential flow. Similar behavior was observed at the loamy plots, where large areas in the upper layers remained dry, displaying signs of strong water repellency. This was confirmed by WDPT tests, which revealed, in all except one plot, moderate to severe water repellency. Water repellency was also accountable for the change of regular infiltration to fingered flow in the sandy soils. The results of this study suggest that the "drought-history" or generally the climatic conditions in the past of a soil are more important than the actual antecedent soil moisture status regarding hydrophobicity and infiltration behavior; and also, that drought effects on infiltration need to be considered in hydrological models to obtain realistic predictions concerning water quality and quantity in runoff and groundwater recharge.

Description: Vertically aligned nanocomposite (VAN) (La 0.7 Sr 0.3 MnO 3 ) 1−x :(CeO 2 ) x (LSMO:CeO 2 ) thin films have been grown on SrTiO 3 (001) substrates by pulsed laser deposition. Tunable magnetoresistance properties as well as microstructures are demonstrated in these VAN films by modulating the film composition (x = 0, 0.3, 0.4, 0.45, 0.5, and 0.55). The sample of x = 0.3 shows a large low-field magnetoresistance (LFMR) in a high temperature range, i.e., over 10% at the range of 280 K to 320 K under 1 T and with a peak value of ∼13.5% at 310 K. In addition, a vast enhancement of LFMR in a low temperature range of 20–150 K with peak of ≈34.3% at 45 K for 1 T could be achieved with x = 0.5. The enhanced LFMR properties can be attributed to both the phase boundary induced spin fluctuation and the magnetic tunneling effect through vertical ferromagnetic/insulator/ferromagnetic structures. The observed enhanced LFMR performance, especially at high temperatures, as well as its simple growth method, offers a great potential for LSMO:CeO 2 nanocomposites to be used in spintronic devices in a large temperature range.

Description: We present a new generalized scaling relationship accounting for relaxation processes of both the real and the imaginary parts of the complex dielectric permittivity data in a wide temperature range of dielectric media. It has been successfully used for experimental data related to various dynamics in liquid crystalline phases of: 4-bromobenzylidene-4′-pentyloxyanilin, 4-bromobenzylidene-4′-hexyloxyaniline, 4′-butyl-4-(2-methylbutoxy) azoxybenzene, and 4-ethyl-4′-octylazoxybenzene. Moreover, the scaling was checked for the theoretical data of Dissado-Hill cluster model. A comparison with earlier scaling, proposed by Nagel and Dendzik, is given.

Description: Focusing of surface phonon-polaritons propagating toward the tip of a cone and the edge of a wedge is theoretically analyzed and compared. Based on Maxwell's equations, explicit expressions for the dispersion relations in each structure are determined and solved numerically for a propagation parameter driving the surface phonon-polariton energy density. For conical and wedge structures of SiO 2 , it is found that: (1) the cone (wedge) supports the polariton focusing only for aperture angles in the interval 18 ° – 68 ° ( 21 ° – 51 ° ), and within the range of excitation frequencies from 32.1 THz (31.5 THz) to 33.9 THz (33.9 THz). In this frequency interval, the real part of the SiO 2 permittivity is negative and the presence of polaritons is significant. (2) The polariton focusing efficiency of both the cone and wedge reaches its maximum values at the critical frequency f cr = 33.6  THz and at different aperture angles of about α opt = 45 ° and α opt = 30 ° , respectively. (3) When the polaritons travel from 100 nm to 5 nm toward the tip of the cone with this optimum angle, their Poynting vector increases by a factor of 12, which is about four times larger than the corresponding one provided by the wedge and indicates that the cone is more efficient than the wedge for the focusing of surface phonon-polaritons.

Description: Surface plasmons can squeeze light into a deep-subwavelength space and generate abundant hot electrons in the nearby metallic regions, enabling a new paradigm of photoconversion by the way of hot electron collection. Unlike the visible spectral range concerned in previous literatures, we focus on the communication band and design the infrared hot-electron photodetectors with plasmonic metal-insulator-metal configuration by using full-wave finite-element method. Titanium dioxide-silver Schottky interface is employed to boost the low-energy infrared photodetection. The photodetection sensitivity is strongly improved by enhancing the plasmonic excitation from a rationally engineered metallic grating, which enables a strong unidirectional photocurrent. With a five-step electrical simulation, the optimized device exhibits an unbiased responsivity of ∼0.1 mA/W and an ultra-narrow response band (FWHM = 4.66 meV), which promises to be a candidate as the compact photodetector operating in communication band.

Description: A two-step method that combines homogeneous electron beam (EB) irradiation and thermal annealing has been developed to enhance the thermoelectric properties of nanocrystalline bismuth selenium telluride thin films. The thin films, prepared using a flash evaporation method, were treated with EB irradiation in a N 2 atmosphere at room temperature and an acceleration voltage of 0.17 MeV. Thermal annealing was performed under Ar/H 2 (5%) at 300 °C for 60 min. X-ray diffraction was used to determine that compositional phase separation between bismuth telluride and bismuth selenium telluride developed in the thin films exposed to higher EB doses and thermal annealing. We propose that the phase separation was induced by fluctuations in the distribution of selenium atoms after EB irradiation, followed by the migration of selenium atoms to more stable sites during thermal annealing. As a result, thin film crystallinity improved and mobility was significantly enhanced. This indicates that the phase separation resulting from the two-step method enhanced, rather than disturbed, the electron transport. Both the electrical conductivity and the Seebeck coefficient were improved following the two-step method. Consequently, the power factor of thin films that underwent the two-step method was enhanced to 20 times (from 0.96 to 21.0  μ W/(cm K 2 ) that of the thin films treated with EB irradiation alone.

Description: In this study, we developed a new method for in-situ pressure determination in multi-anvil, high-pressure apparatus using an acoustic travel time approach within the framework of acoustoelasticity. The ultrasonic travel times of polycrystalline Al 2 O 3 were calibrated against NaCl pressure scale up to 15 GPa and 900 °C in a Kawai-type double-stage multi-anvil apparatus in conjunction with synchrotron X-radiation, thereby providing a convenient and reliable gauge for pressure determination at ambient and high temperatures. The pressures derived from this new travel time method are in excellent agreement with those from the fixed-point methods. Application of this new pressure gauge in an offline experiment revealed a remarkable agreement of the densities of coesite with those from the previous single crystal compression studies under hydrostatic conditions, thus providing strong validation for the current travel time pressure scale. The travel time approach not only can be used for continuous in-situ pressure determination at room temperature, high temperatures, during compression and decompression, but also bears a unique capability that none of the previous scales can deliver, i.e., simultaneous pressure and temperature determination with a high accuracy (±0.16 GPa in pressure and ±17 °C in temperature). Therefore, the new in-situ Al 2 O 3 pressure gauge is expected to enable new and expanded opportunities for offline laboratory studies of solid and liquid materials under high pressure and high temperature in multi-anvil apparatus.

Description: We report a novel method of determining the average Néel relaxation time and its temperature dependence by calculating derivatives of the measured time dependence of temperature for a frozen ferrofluid exposed to an alternating magnetic field. The ferrofluid, composed of dextran-coated Fe 3 O 4 nanoparticles (diameter 13.7 nm ± 4.7 nm), was synthesized via wet chemical precipitation and characterized by x-ray diffraction and transmission electron microscopy. An alternating magnetic field of constant amplitude ( H 0 = 20 kA/m) driven at frequencies of 171 kHz, 232 kHz, and 343 kHz was used to determine the temperature dependent magnetic energy absorption rate in the temperature range from 160 K to 210 K. We found that the specific absorption rate of the ferrofluid decreased monotonically with temperature over this range at the given frequencies. From these measured data, we determined the temperature dependence of the Néel relaxation time and estimate a room-temperature magnetocrystalline anisotropy constant of 40 kJ/m 3 , in agreement with previously published results.

Description: We propose a concurrent multiscale molecular dynamics for molecular systems in order to apply macroscale mechanical boundary conditions such as traction and average displacement for solid state materials, which is difficult to do in traditional molecular dynamics where boundary conditions are applied in terms of forces and displacements on selected particles. The multiscale model is systematically constructed in terms of multiscale structures of kinematics, force field, and dynamical equations. The idea is to extend the Anderson-Parrinello-Rahman molecular dynamics to the cases that have arbitrary finite domain and boundary, thus the model is capable of solving inhomogeneous, non-equilibrium problems. The macroscale stress loading on a representative volume element with periodic boundary condition is generalized to all kinds of macroscale mechanical boundary conditions. Unlike most multiscale techniques, our theory is aimed at understanding fundamental physics rather than achieving computing efficiency. Examples of problems with prescribed average displacements and surface tractions are presented to demonstrate the validity of the proposed multiscale molecular dynamics.

Description: We study the effect of chain rigidity on the behavior of semiflexible polymers in the vicinity of flat walls in a slit, and of surfactants at the liquid-liquid interface between immiscible liquids. Using molecular dynamics simulations, it is demonstrated that the impact of bending angle forces is particularly strong within the depletion layer at the phase boundary whereas at distance R e away from the interface, where R e is the mean distance between the ends of a semiflexible chain, the contribution of these non-local triplet interactions to pressure tensor virtually disappears. The present study also demonstrates that growing stiffness of the macromolecules leads to an increase in surface tension and total pressure.

Description: Quantum-chemical computations of nuclear quadrupole-coupling parameters for 24 open-shell states of small molecules based on non-relativistic and spin-free exact two-component (SFX2C) relativistic equation-of-motion coupled-cluster (EOM-CC) as well as spin-orbital-based restricted open-shell Hartree-Fock coupled-cluster (ROHF-CC) methods are reported. Relativistic effects, the performance of the EOM-CC and ROHF-CC methods for treating electron correlation, as well as basis-set convergence have been carefully analyzed. Consideration of relativistic effects is necessary for accurate calculations on systems containing third-row (K-Kr) and heavier elements, as expected, and the SFX2C approach is shown to be a useful cost-effective option here. Further, it is demonstrated that the EOM-CC methods constitute flexible and accurate alternatives to the ROHF-CC methods in the calculations of nuclear quadrupole-coupling parameters for open-shell states.

Description: We study the continuity of an abstract generalization of the maximum-entropy inference—a maximizer. It is defined as a right-inverse of a linear map restricted to a convex body which uniquely maximizes on each fiber of the linear map a continuous function on the convex body. Using convex geometry we prove, amongst others, the existence of discontinuities of the maximizer at limits of extremal points not being extremal points themselves and apply the result to quantum correlations. Further, we use numerical range methods in the case of quantum inference which refers to two observables. One result is a complete characterization of points of discontinuity for 3 × 3 matrices.

Description: State determination of catalytic converters based on an ultra-wideband communication system Journal of Sensors and Sensor Systems, 4, 255-262, 2015 Author(s): I. Motroniuk, R. Stöber, and G. Fischerauer A novel microwave-based approach for monitoring the state of aftertreatment systems such as diesel particulate filters (DPFs), three-way catalytic converters (TWCs), and selective catalytic reduction (SCR) catalysts is proposed. The volume inside the metallic housing of the DPF, TWC, or SCR is considered as a wireless communication channel between two terminals of a communication system. It is shown that, depending on the transmission channel characteristics, the properties of the catalyst, such as the catalyst state, can be inferred. This is done by means of an ultra-wideband (UWB) measurement and the subsequent evaluation and processing of the waveform in the time and frequency domains.

Description: The monthly cycle of daily food intake among adult participants in the Supplemental Nutrition Assistance Program is examined using data from the 2007–10 National Health and Nutrition Examination Survey. Exogenous variation in interview and benefit receipt dates provides means for identification, and a difference-in-differences specification is used to account for the large boost in benefits that began in April 2009 via the American Recovery and Reinvestment Act (ARRA). Caloric intake declined as much as 25% at the end of the month prior to ARRA, but not after implementation. Few differences were observed for diet quality measures or among subgroups. Increases in SNAP benefit amounts may help smooth food intake over the benefit month.

Description: Many applied economics journals ban the use of deception in experiments, which contrasts with the policies in other academic disciplines. We examine the cases for and against deception, and describe the ways deception can be employed in applied economics experiments. We create a general ranking of harms from deception in experiments and present evidence from a survey (conducted in summer 2014) of agricultural and applied economists eliciting attitudes towards ten different deceptive practices. Survey respondents view inflicting physical or psychological harm on participants and not making promised payments as the most severe forms of deception. Less severe forms of deception include providing participants with incomplete product information and conducting an experiment using participants who are not aware they are part of an experiment. Finally, we provide recommendations for policies addressing deception in experiments.

Description: Existing economic analysis of corn stover as an energy feedstock has not considered potential changes in land use associated with different stover prices. We estimate the response of corn stover supply density to its price driven by changes in land use and examine its implications for a processing plant's pricing strategy and marginal cost, as well as associated changes in soil erosion. We find that plants will exploit the intensive margin as well as the extensive margin to secure additional amounts of stover. Our results show, counterintuitively, that a market for stover may result in lower soil erosion due to reallocations of land to continuous corn with removal, which, combined with no-till farming, results in lower soil erosion than the baseline without stover removal. Also contrary to expectations, using cover crops with stover removal may result in higher soil erosion due to land use changes within the fuel shed associated with optimal pricing.

Description: A quantum two-path interferometer allows for direct measurement of the transmission phase shift of an electron, providing useful information on coherent scattering problems. In mesoscopic systems, however, the two-path interference is easily smeared by contributions from other paths, and this makes it difficult to observe the true transmission phase shift. To eliminate this problem, multi-terminal Aharonov-Bohm (AB) interferometers have been used to derive the phase shift by assuming that the relative phase shift of the electrons between the two paths is simply obtained when a smooth shift of the AB oscillations is observed. Nevertheless, the phase shifts using such a criterion have sometimes been inconsistent with theory. On the other hand, we have used an AB ring contacted to tunnel-coupled wires and acquired the phase shift consistent with theory when the two output currents through the coupled wires oscillate with well-defined anti-phase. Here, we investigate thoroughly these two criteria used to ensure a reliable phase measurement, the anti-phase relation of the two output currents, and the smooth phase shift in the AB oscillation. We confirm that the well-defined anti-phase relation ensures a correct phase measurement with a quantum two-path interference. In contrast, we find that even in a situation where the anti-phase relation is less well-defined, the smooth phase shift in the AB oscillation can still occur but does not give the correct transmission phase due to contributions from multiple paths. This indicates that the phase relation of the two output currents in our interferometer gives a good criterion for the measurement of the true transmission phase, while the smooth phase shift in the AB oscillation itself does not.

Description: A comparison of chemical mechanisms using tagged ozone production potential (TOPP) analysis Atmospheric Chemistry and Physics, 15, 8795-8808, 2015 Author(s): J. Coates and T. M. Butler Ground-level ozone is a secondary pollutant produced photochemically from reactions of NO x with peroxy radicals produced during volatile organic compound (VOC) degradation. Chemical transport models use simplified representations of this complex gas-phase chemistry to predict O 3 levels and inform emission control strategies. Accurate representation of O 3 production chemistry is vital for effective prediction. In this study, VOC degradation chemistry in simplified mechanisms is compared to that in the near-explicit Master Chemical Mechanism (MCM) using a box model and by "tagging" all organic degradation products over multi-day runs, thus calculating the tagged ozone production potential (TOPP) for a selection of VOCs representative of urban air masses. Simplified mechanisms that aggregate VOC degradation products instead of aggregating emitted VOCs produce comparable amounts of O 3 from VOC degradation to the MCM. First-day TOPP values are similar across mechanisms for most VOCs, with larger discrepancies arising over the course of the model run. Aromatic and unsaturated aliphatic VOCs have the largest inter-mechanism differences on the first day, while alkanes show largest differences on the second day. Simplified mechanisms break VOCs down into smaller-sized degradation products on the first day faster than the MCM, impacting the total amount of O 3 produced on subsequent days due to secondary chemistry.

Description: Size distribution and optical properties of mineral dust aerosols transported in the western Mediterranean Atmospheric Chemistry and Physics Discussions, 15, 21607-21669, 2015 Author(s): C. Denjean, F. Cassola, A. Mazzino, S. Triquet, S. Chevaillier, N. Grand, T. Bourrianne, G. Momboisse, K. Sellegri, A. Schwarzenbock, E. Freney, M. Mallet, and P. Formenti This study presents in situ aircraft measurements of Saharan mineral dust transported over the western Mediterranean basin in June–July 2013 during the ChArMEx/ADRIMED (the Chemistry-Aerosol Mediterranean Experiment/Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region) airborne campaign. Dust events differing in terms of source region (Algeria, Tunisia and Morocco), time of tranport (1–5 days) and height of transport were sampled. Mineral dust were transported above the marine boundary layer, which conversely was dominated by pollution and marine aerosols. The dust vertical structure was extremely variable and characterized by either a single layer or a more complex and stratified structure with layers originating from different source regions. Mixing of mineral dust with pollution particles was observed depending on the height of transport of the dust layers. Dust layers carried higher concentration of pollution particles at intermediate altitude (1–3 km) than at elevated altitude (〉 3 km), resulting in scattering Angstrom exponent up to 2.2 within the intermediate altitude. However, the optical properties of the dust plumes remained practically unchanged with respect to values previously measured over source regions, regardless of the altitude. Moderate light absorption of the dust plumes was observed with values of aerosol single scattering albedo at 530 nm ranging from 0.90 to 1.00 ± 0.04. Concurrent calculations from the aerosol chemical composition revealed a negligible contribution of pollution particles to the absorption properties of the dust plumes that was due to a low contribution of refractory black carbon in regards to the fraction of dust and sulfate particles. This suggests that, even in the presence of moderate pollution, likely a persistent feature in the Mediterranean, the optical properties of the dust plumes could be assimilated to those of native dust in radiative transfer simulations, modeling studies and satellite retrievals over the Mediterranean. Measurements also showed that the coarse mode of mineral dust was conserved even after 5 days of transport in the Mediterranean, which contrasts with the gravitational depletion of large particles observed during the transport of dust plumes over the Atlantic. Simulations with the WRF mesoscale meteorological model highlighted a strong vertical turbulence within the dust layers that could prevent deposition of large particles during their atmospheric transport. This has important implications for the dust radiative effects due to surface dimming, atmospheric heating and cloud formation. The results presented here add to the observational dataset necessary for evaluating the role of mineral dust on the regional climate and rainfall patterns in the western Mediterranean basin.

Description: Identification of particulate organosulfates in three megacities at the middle and lower reaches of the Yangtze River Atmospheric Chemistry and Physics Discussions, 15, 21415-21448, 2015 Author(s): X. K. Wang, S. Rossignol, Y. Ma, L. Yao, M. Y. Wang, J. M. Chen, C. George, and L. Wang PM 2.5 filter samples have been collected in three megacities i.e., Wuhan (WH), Nanjing (NJ), and Shanghai (SH) at the middle and lower reaches of the Yangtze River, respectively. Analysis of those samples using an ultra-high performance liquid chromatography (UHPLC) coupled to an orbitrap mass spectrometer (MS) allowed detection of about two hundred particulate organosulfates (OSs), including dozens of nitrooxy-organosulfates, at each location. While aliphatic OSs represented more than 78 % of the detected OSs at the three locations, aromatic OSs were much less abundant. OSs with two to four isomers accounted for about 50 % of the total OSs on average in these megacities, and the percentage of OSs with six and more isomers in WH was more significant than those in SH and NJ. The average molecular weight, and the degrees of oxidation and saturation of OSs in the WH summer samples were greater than those in WH winter samples. In SH, the average molecular weight and the degree of oxidation of OSs in summer samples were greater than those in winter samples, but the degree of saturation was similar between the two seasons. In summer, the average molecular weight, and the degrees of oxidation and unsaturation of OSs were smallest in WH among the three cities. Between NJ and SH, the average molecular weight and the degree of saturation of OSs were close and the degree of oxidation of OSs in NJ was smaller. Kendrick mass defect diagrams and Van Krevelen diagrams indicated that the characteristics of identified OSs between in NJ and in SH shared better similarity. In addition, the identity and abundance of OSs in SH showed clear seasonal and diurnal variations. OSs in summer were more abundant than they were in winter due to stronger photochemical reactions in summer. The relative abundance of OSs at night was greater than that in the daytime and more nitrooxy-OSs existed at night, probably because of active NO 3 radical chemistry at night. In SH summer samples, OSs with 5 and 10 carbons (C 5 and C 10 ) were the most abundant, indicating the importance of isoprene and monoterpenes as precursors of OSs, whereas the relative abundances of OSs with 8, 9, and more than 14 carbons (C 8 , C 9 , and C 14+ ) were also high in SH winter samples, urging the need to further understand the precursors of OSs.

Description: Trace metal characterization of aerosol particles and cloud water during HCCT 2010 Atmospheric Chemistry and Physics, 15, 8751-8765, 2015 Author(s): K. W. Fomba, D. van Pinxteren, K. Müller, Y. Iinuma, T. Lee, J. L. Collett Jr., and H. Herrmann Trace metal characterization of bulk and size-resolved aerosol and cloud water samples were performed during the Hill Cap Cloud Thuringia (HCCT) campaign. Cloud water was collected at the top of Mt. Schmücke while aerosol samples were collected at two stations upwind and downwind of Mt. Schmücke. Fourteen trace metals including Ti, V, Fe, Mn, Co, Zn, Ni, Cu, As, Sr, Rb, Pb, Cr, and Se were investigated during four full cloud events (FCEs) that fulfilled the conditions of a continuous air mass flow through the three stations. Aerosol particle trace metal concentrations were found to be lower than those observed in the same region during previous field experiments but were within a similar range to those observed in other rural regions in Europe. Fe and Zn were the most abundant elements with concentration ranges of 0.2–111.6 and 1.1–32.1 ng m −3 , respectively. Fe, Mn, and Ti were mainly found in coarse mode aerosols while Zn, Pb, and As were mostly found in the fine mode. Correlation and enrichment factor analysis of trace metals revealed that trace metals such as Ti and Rb were mostly of crustal origin while trace metals such as Zn, Pb, As, Cr, Ni, V, and Cu were of anthropogenic origin. Trace metals such as Fe and Mn were of mixed origins including crustal and combustion sources. Trace metal cloud water concentration decreased from Ti, Mn, Cr, to Co with average concentrations of 9.18, 5.59, 5.54, and 0.46 μg L −1 , respectively. A non-uniform distribution of soluble Fe, Cu, and Mn was observed across the cloud drop sizes. Soluble Fe and Cu were found mainly in cloud droplets with diameters between 16 and 22 μm, while Mn was found mostly in larger drops greater than 22 μm. Fe(III) was the main form of soluble Fe especially in the small and larger drops with concentrations ranging from 2.2 to 37.1 μg L −1 . In contrast to other studies, Fe(II) was observed mainly in the evening hours, implying its presence was not directly related to photochemical processes. Aerosol–cloud interaction did not lead to a marked increase in soluble trace metal concentrations; rather it led to differences in the chemical composition of the aerosol due to preferential loss of aerosol particles through physical processes including cloud drop deposition to vegetative surfaces.

Description: Known and unknown unknowns: the application of ensemble techniques to uncertainty estimation in satellite remote sensing data Atmospheric Measurement Techniques Discussions, 8, 8509-8562, 2015 Author(s): A. C. Povey and R. G. Grainger This paper discusses a best-practice representation of uncertainty in satellite remote sensing data. An estimate of uncertainty is necessary to make appropriate use of the information conveyed by a measurement. Traditional error propagation quantifies the uncertainty in a measurement due to well-understood perturbations in a measurement and auxiliary data – known, quantified "unknowns". The underconstrained nature of most satellite remote sensing observations requires the use of various approximations and assumptions that produce non-linear systematic errors that are not readily assessed – known, unquantifiable "unknowns". Additional errors result from the inability to resolve all scales of variation in the measured quantity – unknown "unknowns". The latter two categories of error are dominant in underconstrained remote sensing retrievals and the difficulty of their quantification limits the utility of existing uncertainty estimates, degrading confidence in such data. This paper proposes the use of ensemble techniques to present multiple self-consistent realisations of a data set as a means of depicting unquantified uncertainties. These are generated using various systems (different algorithms or forward models) believed to be appropriate to the conditions observed. Benefiting from the experience of the climate modelling community, an ensemble provides a user with a more complete representation of the uncertainty as understood by the data producer and greater freedom to consider different realisations of the data.

Description: Improved stratospheric aerosol extinction profiles from SCIAMACHY: validation and sample results Atmospheric Measurement Techniques Discussions, 8, 8353-8383, 2015 Author(s): C. von Savigny, F. Ernst, A. Rozanov, R. Hommel, K.-U. Eichmann, V. Rozanov, J. P. Burrows, and L. W. Thomason Stratospheric aerosol extinction profiles have been retrieved from SCIAMACHY/Envisat measurements of limb-scattered solar radiation. The retrieval is an improved version of an algorithm presented earlier. The retrieved aerosol extinction profiles are compared to co-located aerosol profile measurements with the SAGE II solar occultation instrument at a wavelength of 525 nm. Comparisons were carried out with two versions of the SAGE II data set (version 6.2 and the new version 7.0). In a global average sense the SCIAMACHY and the SAGE II version 7.0 extinction profiles agree to within about 10 % for altitudes above 15 km. Larger relative differences (up to 40 %) are observed at specific latitudes and altitudes. We also find differences between the two SAGE II data versions of up to 40 % for specific latitudes and altitudes. Sample results on the latitudinal and temporal variability of stratospheric aerosol extinction and optical depth during the SCIAMACHY mission period are presented. The results indicate that a series of volcanic eruptions is responsible for the increase in stratospheric aerosol optical depth from 2002 to 2012. Above about 28 km altitude volcanic eruptions are found to have negligible impact in the period 2002 to 2012.

Description: The tropopause inversion layer in baroclinic life cycles experiments: the role of diabatic and mixing processes Atmospheric Chemistry and Physics Discussions, 15, 21495-21537, 2015 Author(s): D. Kunkel, P. Hoor, and V. Wirth Recent studies on the formation of a quasi-permanent layer of enhanced static stability above the thermal tropopause revealed the contributions of dynamical and radiative processes. Dry dynamics lead to the evolution of a tropopause inversion layer (TIL) which is, however, too weak compared to observations and thus diabatic contributions are required. In this study we aim to assess the importance of diabatic as well as mixing processes in the understanding of TIL formation at midlatitudes. The non-hydrostatic model COSMO is applied in an idealized mid-latitude channel configuration to simulate baroclinic life cycles. The effect of individual diabatic, i.e. related to humidity and radiation, and turbulent processes is studied first to estimate the additional contribution of these processes to dry dynamics. In a second step these processes are stepwise included in the model to increase the complexity and finally estimate the relative importance of each process. The results suggest that including turbulence leads to a weaker TIL than in a dry reference simulation. In contrast, the TIL evolves stronger when radiation is included but the temporal occurrence is still comparable to the reference. Using various cloud schemes in the model shows that latent heat release and consecutive increased vertical motions foster an earlier and stronger appearance of the TIL than in all other life cycles. Furthermore, updrafts moisten the upper troposphere and as such increase the radiative effect from water vapor. Particularly, this process becomes more relevant for maintaining the TIL during later stages of the life cycles. Increased convergence of the vertical wind induced by updrafts and by propagating and potentially dissipating inertia-gravity waves further contributes to the enhanced stability of the lower stratosphere. Furthermore, radiative feedback of ice clouds reaching up to the tropopause is identified to potentially further affect the strength of the TIL in the region of the cloud.

Description: : As sequencing becomes cheaper and more widely available, there is a greater need to quickly and effectively analyze large-scale genomic data. While the functionality of AVIA v1.0, whose implementation was based on ANNOVAR, was comparable with other annotation web servers, AVIA v2.0 represents an enhanced web-based server that extends genomic annotations to cell-specific transcripts and protein-level functional annotations. With AVIA’s improved interface, users can better visualize their data, perform comprehensive searches and categorize both coding and non-coding variants. Availability and implementation : AVIA is freely available through the web at http://avia.abcc.ncifcrf.gov . Contact : Hue.Vuong@fnlcr.nih.gov Supplementary information: Supplementary data are available at Bioinformatics online.

Description: : As new methods for multivariate analysis of genome wide association studies become available, it is important to be able to combine results from different cohorts in a meta-analysis. The R package MultiMeta provides an implementation of the inverse-variance-based method for meta-analysis, generalized to an n -dimensional setting. Availability and implementation: The R package MultiMeta can be downloaded from CRAN. Contact: dragana.vuckovic@burlo.trieste.it ; vi1@sanger.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online.

Description: The stability of a long scale equilibrium vortex structure to short scale perturbations is studied in a strongly coupled dusty plasma in the framework of a generalized hydrodynamic model. It is shown that the free energy associated with the velocity shear of the vortex can drive secondary instabilities consisting of transverse shear waves when the resonance condition between the vortex rotation frequency and the secondary wave frequency is met. Such a process can transfer energy from the long scale vortex to the short scale secondary wave and thereby provide a saturation mechanism for long scale vortices in plasmas in a manner analogous to that in neutral fluids.

Description: A laser produced high-Z plasma in which an energy balance is achieved due to radiation emission and radiative heat transfer supports ion acoustic instability. A linear dispersion relation is derived, and instability is compared to the radiation cooling instability [R. G. Evans, Plasma Phys. Controlled Fusion 27 , 751 (1985)]. Under conditions of indirect drive fusion experiments, the driving term for the instability is the radiative heat flux and, in particular, the density dependence of the radiative heat conductivity. A specific example of thermal Bremsstrahlung radiation source has been considered. This instability may lead to plasma jet formation and anisotropic x-ray generation, thus affecting inertial confinement fusion related experiments.

Description: The present paper is devoted to simulation of nonlinear disintegration of a localized perturbation into ion-acoustic solitons train in a plasma with hot electrons and cold ions. A Gaussian initial perturbation is used to model the localized perturbation. For this purpose, first, we reduce fluid system of equations to a Korteweg de-Vries equation by the following well-known assumptions. (i) On the ion-acoustic evolution time-scale, the electron velocity distribution function (EVDF) is assumed to be stationary. (ii) The calculation is restricted to small amplitude cases. Next, in order to generalize the model to finite amplitudes cases, the evolution of EVDF is included. To this end, a hybrid code is designed to simulate the case, in which electrons dynamics is governed by Vlasov equation, while cold ions dynamics is, like before, studied by the fluid equations. A comparison between the two models shows that although the fluid model is capable of demonstrating the general features of the process, to have a better insight into the relevant physics resulting from the evolution of EVDF, the use of kinetic treatment is of great importance.

Description: Impact of model developments on present and future simulations of permafrost in a global land-surface model The Cryosphere, 9, 1505-1521, 2015 Author(s): S. E. Chadburn, E. J. Burke, R. L. H. Essery, J. Boike, M. Langer, M. Heikenfeld, P. M. Cox, and P. Friedlingstein There is a large amount of organic carbon stored in permafrost in the northern high latitudes, which may become vulnerable to microbial decomposition under future climate warming. In order to estimate this potential carbon–climate feedback it is necessary to correctly simulate the physical dynamics of permafrost within global Earth system models (ESMs) and to determine the rate at which it will thaw. Additional new processes within JULES, the land-surface scheme of the UK ESM (UKESM), include a representation of organic soils, moss and bedrock and a modification to the snow scheme; the sensitivity of permafrost to these new developments is investigated in this study. The impact of a higher vertical soil resolution and deeper soil column is also considered. Evaluation against a large group of sites shows the annual cycle of soil temperatures is approximately 25 % too large in the standard JULES version, but this error is corrected by the model improvements, in particular by deeper soil, organic soils, moss and the modified snow scheme. A comparison with active layer monitoring sites shows that the active layer is on average just over 1 m too deep in the standard model version, and this bias is reduced by 70 cm in the improved version. Increasing the soil vertical resolution allows the full range of active layer depths to be simulated; by contrast, with a poorly resolved soil at least 50 % of the permafrost area has a maximum thaw depth at the centre of the bottom soil layer. Thus all the model modifications are seen to improve the permafrost simulations. Historical permafrost area corresponds fairly well to observations in all simulations, covering an area between 14 and 19 million km 2 . Simulations under two future climate scenarios show a reduced sensitivity of permafrost degradation to temperature, with the near-surface permafrost loss per degree of warming reduced from 1.5 million km 2 °C −1 in the standard version of JULES to between 1.1 and 1.2 million km 2 °C −1 in the new model version. However, the near-surface permafrost area is still projected to approximately half by the end of the 21st century under the RCP8.5 scenario.

Description: Numerical simulations of the Cordilleran ice sheet through the last glacial cycle The Cryosphere Discussions, 9, 4147-4203, 2015 Author(s): J. Seguinot, I. Rogozhina, A. P. Stroeven, M. Margold, and J. Kleman Despite more than a century of geological observations, the Cordilleran ice sheet of North America remains poorly understood in terms of its former extent, volume and dynamics. Although geomorphological evidence is abundant, its complexity is such that whole ice-sheet reconstructions of advance and retreat patterns are lacking. Here we use a numerical ice sheet model calibrated against field-based evidence to attempt a quantitative reconstruction of the Cordilleran ice sheet history through the last glacial cycle. A series of simulations is driven by time-dependent temperature offsets from six proxy records located around the globe. Although this approach reveals large variations in model response to evolving climate forcing, all simulations produce two major glaciations during marine oxygen isotope stages 4 (61.9–56.5 ka) and 2 (23.2–16.8 ka). The timing of glaciation is better reproduced using temperature reconstructions from Greenland and Antarctic ice cores than from regional oceanic sediment cores. During most of the last glacial cycle, the modelled ice cover is discontinuous and restricted to high mountain areas. However, widespread precipitation over the Skeena Mountains favours the persistence of a central ice dome throughout the glacial cycle. It acts as a nucleation centre before the Last Glacial Maximum and hosts the last remains of Cordilleran ice until the middle Holocene (6.6–6.2 ka).

Description: Coherence oscillations measured in two-dimensional (2D) electronic spectra of pigment-protein complexes may have electronic, vibrational, or mixed-character vibronic origins, which depend on the degree of electronic-vibrational mixing. Oscillations from intrapigment vibrations can obscure the inter-site coherence lifetime of interest in elucidating the mechanisms of energy transfer in photosynthetic light-harvesting. Huang-Rhys factors ( S ) for low-frequency vibrations in Chlorophyll and Bacteriochlorophyll are quite small ( S ≤ 0.05), so it is often assumed that these vibrations influence neither 2D spectra nor inter-site coherence dynamics. In this work, we explore the influence of S within this range on the oscillatory signatures in simulated 2D spectra of a pigment heterodimer. To visualize the inter-site coherence dynamics underlying the 2D spectra, we introduce a formalism which we call the “site-probe response.” By comparing the calculated 2D spectra with the site-probe response, we show that an on-resonance vibration with Huang-Rhys factor as small as S = 0.005 and the most strongly coupled off-resonance vibrations ( S = 0.05) give rise to long-lived, purely vibrational coherences at 77 K. We moreover calculate the correlation between optical pump interactions and subsequent entanglement between sites, as measured by the concurrence. At 77 K, greater long-lived inter-site coherence and entanglement appear with increasing S . This dependence all but vanishes at physiological temperature, as environmentally induced fluctuations destroy the vibronic mixing.

Description: We demonstrate high precision controllability of the magnetization reversal nucleation process in [Co/Pd] 8 multilayer films consisting of two sets of bilayers with high and low perpendicular anisotropy, respectively. The anisotropy of the entire film is set by the degree of Co/Pd interfacial mixing during deposition which provides fine control of the anisotropy of an individual bilayer in the multilayer stack. The relative number of each type of bilayer is used to select the magnetisation reversal behavior such that changing one bilayer changes the properties of the entire multilayer through anisotropy averaging. A simple extension to the sputtering protocol would provide multilayer films with fully graded anisotropy, while maintaining a constant saturation magnetization opening new possibilities for the creation of highly engineered multilayer structures for spin torque devices and future magnetic recording media.

Description: Coherence oscillations measured in two-dimensional (2D) electronic spectra of pigment-protein complexes may have electronic, vibrational, or mixed-character vibronic origins, which depend on the degree of electronic-vibrational mixing. Oscillations from intrapigment vibrations can obscure the inter-site coherence lifetime of interest in elucidating the mechanisms of energy transfer in photosynthetic light-harvesting. Huang-Rhys factors ( S ) for low-frequency vibrations in Chlorophyll and Bacteriochlorophyll are quite small ( S ≤ 0.05), so it is often assumed that these vibrations influence neither 2D spectra nor inter-site coherence dynamics. In this work, we explore the influence of S within this range on the oscillatory signatures in simulated 2D spectra of a pigment heterodimer. To visualize the inter-site coherence dynamics underlying the 2D spectra, we introduce a formalism which we call the “site-probe response.” By comparing the calculated 2D spectra with the site-probe response, we show that an on-resonance vibration with Huang-Rhys factor as small as S = 0.005 and the most strongly coupled off-resonance vibrations ( S = 0.05) give rise to long-lived, purely vibrational coherences at 77 K. We moreover calculate the correlation between optical pump interactions and subsequent entanglement between sites, as measured by the concurrence. At 77 K, greater long-lived inter-site coherence and entanglement appear with increasing S . This dependence all but vanishes at physiological temperature, as environmentally induced fluctuations destroy the vibronic mixing.

Description: Electrochemical in operando X-ray diffraction (XRD) is a powerful method to analyze structural changes of energy storage materials while inserting/de-inserting charge carriers, such as Li- or Na-ions, into/from a host structure. The design of an XRD in operando cell is presented, which enables the use of thin (6 μ m) aluminum foil as X-ray window as a non-toxic alternative to conventional beryllium windows. Owing to the reduced thickness, diffraction patterns and their changes during cycling can be observed with excellent quality, which was demonstrated for two cathode materials for sodium-ion batteries in a half-cell set-up, P2-Na 0.7 MnO 2 and Na 2.55 V 6 O 16 ⋅ 0.6H 2 O.

Description: Publication date: Available online 7 August 2015 Source: FEBS Open Bio Author(s): Kimberley J. Anderson, Aaron P. Russell, Victoria C. Foletta The function of the stress-responsive N-myc downstream-regulated gene 2 (NDRG2) in the control of myoblast growth, and the amino acids contributing to its function, are not well characterised. Here, we investigated the effect of increased NDRG2 levels on the proliferation, differentiation and apoptosis in skeletal muscle cells under basal and stress conditions. NDRG2 overexpression increased C2C12 myoblast proliferation and the expression of positive cell cycle regulators, cdk2, cyclin B and cyclin D, and phosphorylation of Rb, while the serine/threonine-deficient NDRG2, 3A-NDRG2, had less effect. The onset of differentiation was enhanced by NDRG2 as determined through the myogenic regulatory factor expression profiles and myocyte fusion index. However, the overall level of differentiation in myotubes was not different. While NDRG2 up-regulated caspase 3/7 activities during differentiation, no increase in apoptosis was measured by TUNEL assay or through cleavage of caspase 3 and PARP proteins. During H 2 O 2 treatment to induce oxidative stress, NDRG2 helped protect against the loss of proliferation and ER stress as measured by GRP78 expression with 3A-NDRG2 displaying less protection. NDRG2 also attenuated apoptosis by reducing cleavage of PARP and caspase 3 and expression of pro-apoptotic Bax while enhancing the pro-survival Bcl-2 and Bcl-xL levels. In contrast, Mcl-1 was not altered, and NDRG2 did not protect against palmitate-induced lipotoxicity. Our findings show that NDRG2 overexpression increases myoblast proliferation and caspase 3/7 activities without increasing overall differentiation. Furthermore, NDRG2 attenuates H 2 O 2 -induced oxidative stress and specific serine and threonine amino acid residues appear to contribute to its function in muscle cells.

Description: Stimulated Brillouin scattering during electron gyro-harmonic heating at EISCAT Annales Geophysicae, 33, 983-990, 2015 Author(s): H. Y. Fu, W. A. Scales, P. A. Bernhardt, S. J. Briczinski, M. J. Kosch, A. Senior, M. T. Rietveld, T. K. Yeoman, and J. M. Ruohoniemi Observations of secondary radiation, stimulated electromagnetic emission (SEE), produced during ionospheric modification experiments using ground-based, high-power, high-frequency (HF) radio waves are considered. The High Frequency Active Auroral Research Program (HAARP) facility is capable of generating narrowband SEE in the form of stimulated Brillouin scatter (SBS) and stimulated ion Bernstein scatter (SIBS) in the SEE spectrum. Such narrowband SEE spectral lines have not been reported using the European Incoherent Scatter (EISCAT) heater facility before. This work reports the first EISCAT results of narrowband SEE spectra and compares them to SEE previously observed at HAARP during electron gyro-harmonic heating. An analysis of experimental SEE data shows observations of emission lines within 100 Hz of the pump frequency, interpreted as SBS, during the 2012 July EISCAT campaign. Experimental results indicate that SBS strengthens as the pump frequency approaches the third electron gyro-harmonic. Also, for different heater antenna beam angles, the CUTLASS radar backscatter induced by HF radio pumping is suppressed near electron gyro-harmonics, whereas electron temperature enhancement weakens as measured by EISCAT/UHF radar. The main features of these new narrowband EISCAT observations are generally consistent with previous SBS measurements at HAARP.

Description: We present a method for noninvasively imaging the hand joints using a three-dimensional (3D) photoacoustic imaging (PAI) system. This 3D PAI system utilizes cylindrical scanning in data collection and virtual-detector concept in image reconstruction. The maximum lateral and axial resolutions of the PAI system are 70  μ m and 240  μ m. The cross-sectional photoacoustic images of a healthy joint clearly exhibited major internal structures including phalanx and tendons, which are not available from the current photoacoustic imaging methods. The in vivo PAI results obtained are comparable with the corresponding 3.0 T MRI images of the finger joint. This study suggests that the proposed method has the potential to be used in early detection of joint diseases such as osteoarthritis.

Description: We show how to levitate a liquid droplet above a plasma. Submitting a conductive droplet to a voltage larger than 50 V, we get a levitation regime that looks like the one obtained with the well-known thermal Leidenfrost effect, except that light is emitted from beneath the droplet. Spectroscopic analysis shows that this light is emitted by a cold and dense plasma and also that lines coming from the cathode plate material are present revealing a local cathodic sputtering effect. We examine the conditions for the levitation to occur and show that the levitation is essentially of thermal origin. Assuming a stationary heat transfer, we present a model that accounts well for the observed levitation conditions. In particular, stable levitation is shown to be possible for thin cathode plates only.

Description: We have performed atomistic simulations of the phonon-limited high field carrier transport in ⟨ 110 ⟩ Si nanowires with small diameter. The carrier drift velocities are obtained from a direct solution of the non-linear Boltzmann transport equation. The relationship between the drift velocity and the electric field considerably depends on the carrier, temperature, and diameter of the nanowires. In particular, the threshold between the linear and non-linear regimes exhibits important variations. The drift velocity reaches a maximum value and then drops. These trends can be related to the effects of quantum confinement on the band structure of the nanowires. We also discuss the impact of the different phonon modes and show that high-energy phonons can, unexpectedly, increase the drift velocity at a high electric field.

Description: Ion implantation is proposed to produce self-standing bent monocrystals. A Si sample 0.2 mm thick was bent to a radius of curvature of 10.5 m. The sample curvature was characterized by interferometric measurements; the crystalline quality of the bulk was tested by X-ray diffraction in transmission geometry through synchrotron light at ESRF (Grenoble, France). Dislocations induced by ion implantation affect only a very superficial layer of the sample, namely, the damaged region is confined in a layer 1  μ m thick. Finally, an elective application of a deformed crystal through ion implantation is here proposed, i.e., the realization of a crystalline undulator to produce X-ray beams.

Description: One-dimensional (1D) nanotubes of Nd 0.1 Bi 0.9 FeO 3 (NBFO) with an inner diameter of ∼50 nm were synthesized via sol-gel based electrospinning without template assistant. The phases, morphologies, crystalline structures, and magnetic properties of these 1D nanostructures were characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and SQUID, respectively. It was found that the calcination condition plays a crucial role in determining the morphologies and the magnetic properties. Interestingly, these 1D NBFO nanotubes exhibit wasp-waisted magnetic hysteresis with a lower coercivity and larger saturation magnetization, which were prevalent in natural rocks and artificial composite materials. The origin of these wasp-waisted hysteresis loops was discussed.

Description: Atmospheric pressure pulsed helium plasma jets are utilized for plasma-cell interactions. The effect of operating parameters such as applied voltage, pulse repetition frequency, and duty ratio on the generation of specific reactive oxygen and nitrogen species in gas and liquid phases and within cells is investigated. The apoptotic changes detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling assay in cells caused by plasma exposure are observed to correlate well with the levels of extracellular and intracellular reactive oxygen and nitrogen species.

Description: We report photovoltaic response of highly transparent graphene/BiFe 0.95 Si 0.05 O 3 (BFSiO)/ITO/glass derived from bottom-up spin coating technique. The device exhibits short-circuit-current (I SC 0.75 mA) with 1000 fold upsurge and open-circuit-voltage (V OC  ∼ 0.45 V) under standard AM 1.5 illumination through graphene. In combination, I SC of 0.63 mA and V OC of 0.35 V for same illumination through ITO, reveals the prospects of harvesting indoor light. Also, crystallographic structure, red shift in band gap, leakage behavior, and ferroelectric characteristics of BFSiO thin films are reported. Reproducible transient response of I SC and V OC with quick switching (

Description: Physical insights on the hydrodynamics and locomotion of self-propelled nanowire motor under nonequilibrium steady state are investigated using finite element method in accordance with hybrid molecular dynamics/multiparticle collision dynamics and rigid body dynamics. Nanowire motor is discretized into finite segments, and forces of solvent molecule acting on the motor are assumed to be the sum of forces acting on all segments of the motor. We show that the locomotion of nanowire motor is mainly determined by the imbalance forces acting on the catalytic and noncatalytic segments. The average velocity along the axis increases significantly as a function of time prior to reaching equilibrium. The length of nanowire motor shows negligible effect on the velocity of the motor. Preliminary experimental results are provided to validate the current model.

Description: Ultrahigh density periodically ordered magnetic yttrium iron garnet (Y 3 Fe 5 O 12 , YIG) nanodot arrays have been prepared by pulsed laser deposition through an ultrathin alumina mask (UTAM). UTAM having periodically ordered circularly shaped holes with 350 nm in diameter, 450 nm in inter-pore distance, and 700 nm in height has been prepared on silicon substrate. Furthermore, the microstructure and magnetic properties of YIG nanodot arrays have been characterized. Nanodot arrays with a sharp distribution in diameter centered at 340 nm with standard deviation of 10 nm have been fabricated. Moreover, typical hysteresis loops and ferromagnetic resonance spectra in in-plane and out-of-plane revealed that this unique structure greatly influences the magnetics properties of YIG. First, coercivity of YIG nanodot arrays in in-plane was increased about from 15 Oe of YIG films to 500 Oe. Then, the degree of uniformity about nanodot height decided that two or more resonance peaks in out-of-plane were detected in the spectra. The peak-to-peak linewidth values were about 94 Oe and 40 Oe in the parallel and perpendicular directions, respectively, which indicated that the values were larger by the two-magnon scattering. Consequently, this pattering method creates opportunities for studying physics in oxide nanomagnets and may be applied in spin-wave devices.

Description: We report on the tuning of the optical properties of II-VI-material-based microcavity samples, which is achieved by depositing Ag films on top of the structures. The micro-reflectivity spectra show a spectral shift of the sample resonance dependent on the metal layer thickness. By comparison of the experimental findings with the theoretical calculations applying the transfer matrix method on a metal-dielectric mirror structure, the influence of the metal layer particularly with regard to its partial oxidation was explored. Tamm plasmon modes are created at the interface between an open cavity with three ZnSe quantum wells and a metal layer on top. When tuning the excitonic emission relative to the mode by changing the sample temperature, an anticrossing of the resonances was observed. This is a clear indication that the strong coupling regime has been achieved in that sample configuration yielding a Rabi splitting of 18.5 meV. These results are promising for the realization of polariton-based optical devices with a rather simple sample configuration.

Description: Optimizing the impact of temperature on bio-hydrogen production from food waste and its derivatives under no pH control using statistical modelling Biogeosciences Discussions, 12, 12823-12850, 2015 Author(s): A. Sattar, C. Arslan, C. Ji, S. Sattar, K. Yousaf, and S. Hashim The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 °C) to thermophilic (55 °C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen production from rice waste. The maximum cumulative bio-hydrogen production of 650 mL was obtained from noodle waste under mesophilic temperature condition. Most of the production was observed during 48 h of incubation that continued till 72 h of incubation, and a decline in pH during this interval was 4.3 and 4.4 from a starting value of 7 under mesophilic and thermophilic conditions, respectively. Most of glucose consumption was also observed during 72 h of incubation and the maximum consumption was observed during the first 24 h, which was the same duration where the maximum pH drop occurred. The maximum hydrogen yields of 82.47 mL VS −1 , 131.38 mL COD −1 , and 44.90 mL glucose −1 were obtained from mesophilic food waste, thermophilic noodle waste and mesophilic rice waste respectively. The production of volatile fatty acids increased with an increase in time and temperature from food waste and noodle waste reactors whereas it decreased with temperature in rice waste reactors. The statistical modelling returned good results with high values of coefficient of determination ( R 2 ) for each waste type when it was opted for the study of cumulative hydrogen production, glucose consumption and volatile fatty acid production. The 3-D response surface plots developed by the statistical models helped a lot in developing better understanding of the impact of temperature and incubation time.

Description: Characterization and source apportionment of organic aerosol using offline aerosol mass spectrometry Atmospheric Measurement Techniques Discussions, 8, 8599-8644, 2015 Author(s): K. R. Daellenbach, C. Bozzetti, A. Křepelová, F. Canonaco, R. Wolf, P. Zotter, P. Fermo, M. Crippa, J. G. Slowik, Y. Sosedova, Y. Zhang, R.-J. Huang, L. Poulain, S. Szidat, U. Baltensperger, A. S. H. Prévôt, and I. El Haddad Field deployments of the Aerodyne Aerosol Mass Spectrometer (AMS) have significantly advanced real-time measurements and source apportionment of non-refractory particulate matter. However, the cost and complex maintenance requirements of the AMS make impractical its deployment at sufficient sites to determine regional characteristics. Furthermore, the negligible transmission efficiency of the AMS inlet for supermicron particles significantly limits the characterization of their chemical nature and contributing sources. In this study, we utilize the AMS to characterize the water-soluble organic fingerprint of ambient particles collected onto conventional quartz filters, which are routinely sampled at many air quality sites. The method was applied to 256 particulate matter (PM) filter samples (PM 1 , PM 2.5 , PM 10 ) collected at 16 urban and rural sites during summer and winter. We show that the results obtained by the present technique compare well with those from co-located online measurements, e.g. AMS or Aerosol Chemical Speciation Monitor (ACSM). The bulk recoveries of organic aerosol (60–91 %) achieved using this technique, together with low detection limits (0.8 μg of organic aerosol on the analyzed filter fraction) allow its application to environmental samples. We will discuss the recovery variability of individual hydrocarbon, oxygen containing and other ions. The performance of such data in source apportionment is assessed in comparison to ACSM data. Recoveries of organic components related to different sources as traffic, wood burning and secondary organic aerosol are presented. This technique, while subjected to the limitations inherent to filter-based measurements (e.g. filter artifacts and limited time resolution) may be used to enhance the AMS capabilities in measuring size-fractionated, spatially-resolved long-term datasets.

Description: Fluorescence microscopy allows us to observe fluorescently labeled molecules in diverse biological processes and organelle structures within living cells. However, the diffraction limit restricts its spatial resolution to about half of its wavelength, limiting the capability of biological observation at the molecular level. Structured-illumination microscopy (SIM), a type of super-resolution microscopy, doubles the spatial resolution in all three dimensions by illuminating the sample with a patterned excitation light, followed by computer reconstruction. SIM uses a relatively low illumination power compared with other methods of super-resolution microscopy and is easily available for multicolor imaging. SIM has great potential for meeting the requirements of live-cell imaging. Recent developments in diverse types of SIM have achieved higher spatial (~50 nm lateral) and temporal (~100 Hz) resolutions. Here, we review recent advancements in SIM and discuss its application in noninvasive live-cell imaging.

Description: One of the most popular super-resolution microscopies that breaks the diffraction barrier is stimulated emission depletion (STED) microscopy. As the optical set-up of STED microscopy is based on a laser scanning microscopy (LSM) system, it potentially has several merits of LSM like confocal or two-photon excitation LSM. In this article, we first describe the principles of STED microscopy and then describe the features of our newly developed two-photon excitation STED microscopy. On the basis of our recent results and those of other researchers, we conclude by discussing future research and new technologies in this field.

Description: The electrically automated ultrathin sectioning apparatus, which has been developed in recent years, can produce consecutive ultrathin sections with a diamond knife and a gallium ion beam. These newly developed apparatuses, however, have several shortcomings, such as the limited block cutting area, thermal damage to the sample by the focused ion beam and a sample electronic charge. To overcome these faults and for easier scanning electron microscopy three-dimensional fine structural reconstruction, we have developed a new cutting method using a deep ultraviolet laser, which we have named the ‘LANTome (Light Ablation Nanotome)’. Using this method, we confirmed the widening of sectioning areas, shortening of the sectioning time, automatic smoothing of rough surfaces, no sample electronic charge and minimal heat effects on the sample tissue, such as thermal denaturation.

Description: Recent advances in nanoscopy, which breaks the diffraction barrier and can visualize structures smaller than the diffraction limit in cells, have encouraged biologists to investigate cellular processes at molecular resolution. Since nanoscopy depends not only on special optics but also on ‘smart’ photophysical properties of photocontrollable fluorescent probes, including photoactivatability, photoswitchability and repeated blinking, it is important for biologists to understand the advantages and disadvantages of fluorescent probes and to choose appropriate ones for their specific requirements. Here, we summarize the characteristics of currently available fluorescent probes based on both proteins and synthetic compounds applicable to nanoscopy and provide a guideline for selecting optimal probes for specific applications.

Description: As one of the most powerful tools in the biological investigation of cellular structures and dynamic processes, fluorescence microscopy has undergone extraordinary developments in the past decades. The advent of super-resolution techniques has enabled fluorescence microscopy – or rather nanoscopy – to achieve nanoscale resolution in living specimens and unravelled the interior of cells with unprecedented detail. The methods employed in this expanding field of microscopy, however, are especially prone to the detrimental effects of optical aberrations. In this review, we discuss how super-resolution microscopy techniques based upon single-molecule switching, stimulated emission depletion and structured illumination each suffer from aberrations in different ways that are dependent upon intrinsic technical aspects. We discuss the use of adaptive optics as an effective means to overcome this problem.

Description: As urbanization continues across the globe, cities face significant challenges and opportunities to grow in ways that reduce carbon emissions while providing high quality of life. An EcoPartnership between the cities of Portland, Oregon, USA and Kunming, China is designed to accelerate the exchange of policies and strategies for low-carbon development. Kunming successfully implemented China's first bus-rapid transit system (BRT); Portland is currently analyzing the feasibility of BRT. Portland relies on an urban growth boundary (UGB) as a key policy to guide growth management; Kunming is evaluating the feasibility of a UGB. Both cities are investing in infrastructure for bicycle networks. Key characteristics of successful collaboration include shared substantive priorities; familiarity with the institutional context and roles of the individuals involved; a good match in the responsibilities of the participating agencies and individuals; interpersonal rapport and trust; and the persistence of the collaboration over time.

Description: We performed a detailed analysis of elemental abundances, dust features, and polycyclic aromatic hydrocarbons (PAHs) in the C-rich planetary nebula (PN) Wray16-423 in the Sagittarius dwarf spheroidal galaxy, based on a unique data set taken from the Subaru/HDS, MPG/ESO FEROS, HST /WFPC2, and Spitzer /IRS. We performed the first measurements of Kr, Fe, and recombination O abundance in this PN. The extremely small [Fe/H] implies that most Fe atoms are in the solid phase, considering into account the abundance of [Ar/H]. The Spitzer /IRS spectrum displays broad 16–24 μm and 30 μm features, as well as PAH bands at 6–9 and 10–14 μm. The unidentified broad 16–24 μm feature may not be related to iron sulphide (FeS), amorphous silicate, or PAHs. Using the spectral energy distribution model, we derived the luminosity and effective temperature of the central star, and the gas and dust masses. The observed elemental abundances and derived gas mass are in good agreement with asymptotic giant branch nucleosynthesis models for an initial mass of 1.90 M and a metallicity of Z  = 0.004. We infer that respectively about 80, 50, and 90 per cent of the Mg, S, and Fe atoms are in the solid phase. We also assessed the maximum possible magnesium sulphide (MgS) and iron-rich sulphide (Fe50S) masses and tested whether these species can produce the band flux of the observed 30 μm feature. Depending on what fraction of the sulphur is in sulphide molecules such as CS, we conclude that MgS and Fe50S could be possible carriers of the 30 μm feature in this PN.

Description: We investigate the evolution of the H β + [O iii ] and [O ii ] luminosity functions from z  ~ 0.8 to ~5 in four redshift slices per emission line using data from the High- z Emission Line Survey (HiZELS). This is the first time that the H β + [O iii ] and [O ii ] luminosity functions have been studied at these redshifts in a self-consistent analysis. This is also the largest sample of [O ii ] and H β + [O iii ] emitters (3475 and 3298 emitters, respectively) in this redshift range, with large comoving volumes ~1  x  10 6  Mpc –3 in two independent volumes (COSMOS and UDS), greatly reducing the effects of cosmic variance. The emitters were selected by a combination of photometric redshift and colour–colour selections, as well as spectroscopic follow-up, including recent spectroscopic observations using DEIMOS and MOSFIRE on the Keck Telescopes and FMOS on Subaru. We find a strong increase in L * and a decrease in * for both H β + [O iii ] and [O ii ] emitters. We derive the [O ii ] star formation history of the Universe since z  ~ 5 and find that the cosmic star formation rate density (SFRD) rises from z  ~ 5 to ~3 and then drops towards z  ~ 0. We also find that our star formation history is able to reproduce the evolution of the stellar mass density up to z  ~ 5 based only on a single tracer of star formation. When comparing the H β + [O iii ] SFRDs to the [O ii ] and H α SFRD measurements in the literature, we find that there is a remarkable agreement, suggesting that the H β + [O iii ] sample is dominated by star-forming galaxies at high- z rather than AGNs.

Description: We present a ‘two-fluid’ implementation of dust in smoothed particle hydrodynamics (SPH) in the test particle limit. The scheme is able to handle both short and long stopping times and reproduces the short friction time limit, which is not properly handled in other implementations. We apply novel tests to verify its accuracy and limitations, including multidimensional tests that have not been previously applied to the drag-coupled dust problem and which are particularly relevant to self-gravitating protoplanetary discs. Our tests demonstrate several key requirements for accurate simulations of gas–dust mixtures. First, in standard SPH particle jitter can degrade the dust solution, even when the gas density is well reproduced. The use of integral gradients, a Wendland kernel and a large number of neighbours can control this, albeit at a greater computational cost. Secondly, when it is necessary to limit the artificial viscosity we recommend using the Cullen & Dehnen switch, since the alternative, using α ~ 0.1, can generate a large velocity noise up to v   0.3 c s in the dust particles. Thirdly, we find that an accurate dust density estimate requires 〉400 neighbours, since, unlike the gas, the dust particles do not feel regularization forces. This density noise applies to all particle-based two-fluid implementations of dust, irrespective of the hydro solver and could lead to numerically induced fragmentation. Although our tests show accurate dusty gas simulations are possible, care must be taken to minimize the contribution from numerical noise.

Description: Halo abundance matching has been used to construct a one-parameter mapping between galaxies and dark matter haloes by assuming that halo mass and galaxy luminosity (or stellar mass) are monotonically related. While this approach has been reasonably successful, it is known that galaxies must be described by at least two parameters, as can be seen from the two-parameter Fundamental Plane on which massive early-type galaxies lie. In this paper, we derive a connection between initial dark matter density perturbations in the early Universe and present-day virialized dark matter haloes by assuming simple spherical collapse combined with conservation of mass and energy. We find that z  = 0 halo concentration, or alternatively the inner slope of the halo density profile α, is monotonically and positively correlated with the collapse redshift of the halo. This is qualitatively similar to the findings of some previous works based on numerical simulations, with which we compare our results. We then describe how the halo mass and concentration (or inner slope α) can be used as two halo parameters in combination with two parameters of early-type galaxies to create an improved abundance matching scheme. In a forthcoming paper, we will show an application of this scheme to galaxies on the Fundamental Plane.

Description: Large surveys have shown that red galaxies are preferentially aligned with their haloes, while blue galaxies have a more isotropic distribution. Since haloes generally align with their filaments, this introduces a bias in the measurement of the cosmic shear from weak lensing. It is therefore vitally important to understand why this difference arises. We explore the stability of different disc orientations within triaxial haloes. We show that, in the absence of gas, the disc orientation is most stable when its spin is along the minor axis of the halo. Instead when gas cools on to a disc, it is able to form in almost arbitrary orientation, including off the main planes of the halo (but avoiding an orientation perpendicular to the halo's intermediate axis). Substructure helps gasless galaxies reach alignment with the halo faster, but has less effect on galaxies when gas is cooling on to the disc. Our results provide a novel and natural interpretation for why red, gas poor galaxies are preferentially aligned with their halo, while blue, star-forming, galaxies have nearly random orientations, without requiring a connection between galaxies’ current star formation rate and their merger history.

Description: Statistical detection and modeling of the over-dispersion of winter storm occurrence Natural Hazards and Earth System Science, 15, 1757-1761, 2015 Author(s): M. Raschke In this communication, I improve the detection and modeling of the over-dispersion of winter storm occurrence. For this purpose, the generalized Poisson distribution and the Bayesian information criterion are introduced; the latter is used for statistical model selection. Moreover, I replace the frequently used dispersion statistics by an over-dispersion parameter which does not depend on the considered return period of storm events. These models and methods are applied in order to properly detect the over-dispersion in winter storm data for Germany, carrying out a joint estimation of the distribution models for different samples.