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  • Wiley-Blackwell  (570,352)
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  • 1
    Publication Date: 2019-02-11
    Description: Aim: The interdependencies between trophic interactions, environmental factors and anthropogenic forcing determine how species distributions change over time. Large changes in species distributions have occurred as a result of climate change. The objective of this study was to analyse how the spatial distribution of cod and flounder has changed in the Baltic Sea during the past four decades characterized by large hydrological changes. Location: Baltic Sea. Taxon: Cod (Gadus morhua) and flounder (Platichthys flesus). Methods: Catch per unit of effort (CPUE) data for adult and juvenile cod and for adult flounder were modelled using Delta-Generalized additive models including environmental and geographical variables between 1979 and 2016. From the annual CPUE predictions for each species, yearly distribution maps and depth distribution curves were obtained. Mean depth and the depth range were estimated to provide an indication on preferred depth and habitat occupancy. Results: Adult and juvenile cod showed a contraction in their distribution in the southern areas of the Baltic Sea. Flounder, instead, showed an expansion in its distribution with an increase in abundance in the northern areas. The depth distributions showed a progressive shift of the mean depth of occurrence towards shallower waters for adult cod and flounder and towards deeper waters for juvenile cod, as well as a contraction of the species depth ranges, evident mainly from the late 1980s. Main conclusions: Our study illustrates large changes in the spatial distribution of cod and flounder in the Baltic Sea. The changes in depth distribution occurred from the late 1980s are probably due to a combination of expanded areas of hypoxia in deep waters and an increase in predation risk in shallow waters. The net effect of these changes is an increased spatial overlap between life stages and species, which may amplify cod cannibalism and the interaction strength between cod and flounder
    Type: Article , PeerReviewed
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  • 2
    Publication Date: 2018-03-09
    Description: This study presents turbulence kinetic energy (TKE) budget terms above tall, deciduous walnut canopy in the wintertime stable boundary layer (SBL) and makes a comparison to well-known results of horizontally-homogeneous and flat (HHF) terrain. Turbulence measurements performed at five levels above the canopy height (approximately h =18 m) enable the investigation of joint effect of the roughness sublayer (RSL) and the transition layer on the TKE budget terms. Each term of the TKE budget is investigated within the framework of local similarity theory. Kolomogorov’s similarity hypothesis assumes local isotropy within the inertial subrange. Thoroughly testing the local isotropy hypothesis for the present data set results in a ratio of the horizontal spectral densities ( S v / S u ) approaching 4/3 , while the ratio of the vertical to the longitudinal spectral density ( S w / S u ) is less than the canonical value of 4/3 (even less than 1) for all levels indicating anisotropic turbulence even at very small scales above the canopy. As a consequence, estimated values of TKE dissipation rate ( ε ) from the vertical component are smaller than those obtained from the horizontal velocity components. This finding has a direct influence on the applicability of classical Kansas spectral models valid for HHF terrain as well as on the budget of wind variances. Additionally, the behavior of the non-dimensional gradient of mean wind speed is tested with regard to conformity to z -less scaling requirements (i.e., linear dependence on stability). It is confirmed that a stability threshold (such as Rf  〉 0.25 , where Rf is the flux Richardson number) is a stronger determinant of z -less behavior than the existence of a well-defined inertial subrange - opposite to observations in the SBL over ideal flat surfaces. Finally, the local equilibrium between the production and destruction of TKE within the RSL and transition layer is analyzed.
    Print ISSN: 0035-9009
    Electronic ISSN: 1477-870X
    Topics: Geography , Physics
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  • 3
    Publication Date: 2018-03-09
    Description: In this paper, we focus on the characteristics of electromagnetic power of characteristic modes (CMs) for magneto-dielectric materials (MDM). A generalized integral form of Poynting's theorem is proposed. Based on the generalized integral form of Poynting's theorem, an explicit formulation for electromagnetic power of traditional VIE (volume integral equation)-based CM and PMCHWT (Poggio, Miller, Chang, Harrington, Wu, and Tsai)-based CM of homogeneous MDM is presented for the first time. Furthermore, from the concept of electromagnetic power, a novel electromagnetic power-based CM for MDM is proposed. Numerical results are given to show that the proposed CM are effective in solving scattering problem.
    Print ISSN: 0048-6604
    Electronic ISSN: 1944-799X
    Topics: Geosciences , Physics
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  • 4
    Publication Date: 2018-03-09
    Description: Verification in the presence of observation errors is approached form the Bayesian point of view. Like data assimilation (DA), Bayesian verification is shown to have a robust foundation established by Bayesian inference. Together, DA and Bayesian verification form two difference levels of Bayesian inference. Evaluation of a model is equivalent to inference on the plausibility of this model given observations. Relative performances between different models are measured by ratios of posterior plausibilities, which becomes ratios of likelihoods in case of no prior information. These ratios are called the Bayes factors and are the standard verification method in Bayesian model comparison. Since verification scores are used intensively in numerical weather prediction, the verification scores derived from likelihoods are proposed to replace the Bayes factors in Bayesian verification. With two requirements that the verification scores are both strictly proper and local, the logarithm score, i.e. log-likelihood, and its linear transformation are shown to be the unique class. Log-likelihoods in Bayesian verification are determined by the form of forecast probability distributions from models. The empirical form is preferable since its flexibility in incorporating not only observation errors but also other uncertainties in observation biases or observation error variances into calculation to obtain closed forms for log-likelihoods. When applied for observations with Gaussian errors, the logarithm score induces the weighted mean squared error which is non-dimensional and can be used for both univariate and multivariate observations. The most interesting application of Bayesian verification is to offer a new explanation for rank histograms and quantify the flatness of rank histograms by a metric which turns out to be the Kullback-Leibler divergence between the rank distribution observed in reality and a uniform rank distribution. It is worthy of note that the two very different metrics come from the logarithm score.
    Print ISSN: 0035-9009
    Electronic ISSN: 1477-870X
    Topics: Geography , Physics
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  • 5
    Publication Date: 2018-03-09
    Description: The basic structure and dynamics of the primary electric current systems in the Earth's magnetosphere is presented and discussed. In geophysics, the word current is used to describe the flow of mass from one location to another, and its analogue of electric current is a flow of charge from one place to another. An electric current is associated with a magnetic field, and they combine with the Earth's internally-generated dipolar magnetic field to form the topology of the magnetosphere. The concept of an electric current is reviewed and compared with other approaches to investigating the physics of the magnetosphere. The implications of understanding magnetospheric current systems is discussed, including paths forward for new investigations with the robust set of observations being produced by the numerous scientific and commercial satellites orbiting Earth.
    Print ISSN: 8755-1209
    Topics: Geosciences
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  • 6
    Publication Date: 2018-03-09
    Description: One of the largest ophiolitic peridotite masses in the world covers a quarter of the island of Grande Terre, New Caledonia. The Peridotite Nappe was obducted during the Eocene, is weakly deformed and corresponds to the highest of a structurally simple pile of thrust nappes. We present new marine seismic data that allows us to track the offshore continuation of the Peridotite Nappe along-strike for a distance of more than 500 km south of New Caledonia, and to image its pre-, syn- and post-obduction sedimentary records. Offshore, the Peridotite Nappe underlies a c. 150-km wide and 2 km-deep basin. Flat-topped horsts of peridotite are clearly bounded by major normal faults; in contrast faults are obscure onland. To the east, the Peridotite Nappe roots along the eastern margin of the Félicité Ridge (new name), a c. 300 x 25 km dome-shaped ridge, which we interpret as being the southern extension of the HP/LT metamorphic core complex observed in New Caledonia. Two alternative tectonic models address the relative timing and relationships between Peridotite Nappe emplacement, uplift of a metamorphic core complex, and extensional tectonics. These models provide new ideas for the understanding the formation of the eastern margin of the Zealandia continent. Our results contribute to an understanding of how oceanic mantle is emplaced onto continental margins.
    Print ISSN: 0278-7407
    Electronic ISSN: 1944-9194
    Topics: Geosciences
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  • 7
    Publication Date: 2018-03-09
    Description: The Andean belt is the only present-day active case example of a subduction-type orogeny. However, an existing controversy opposes classical views of Andean growth as an east-verging retro-wedge, against a recently proposed bi-vergent model involving a primary west-vergent crustal-scale thrust synthetic to the subduction. We examine these diverging views by quantitatively re-evaluating the orogen structural geometry and kinematics at the latitude of 33.5°S. We first provide a 3D-geological map and build an updated section of the east-vergent Aconcagua fold-and-thrust belt (Aconcagua-FTB), which appears as a critical structural unit in this controversy. We combine these data with geological constraints on nearby structures to derive a complete and larger scale section of the Principal Cordillera within the forearc region. We restore our section and integrate published chronological constraints to build an evolutionary model showing the evolving shortening of this forearc part of the Andes. The proposed kinematics implies uplift of the Frontal Cordillera basement since ~20-25 Ma, supported by westward thrusting over a crustal ramp that transfers shortening further west across the Principal Cordillera. The Aconcagua-FTB is evidenced as a secondary east-verging roof thrust atop the large-scale basement antiform culmination of the Frontal Cordillera. We estimate a shortening of ~27-42 km across the Principal Cordillera, of which only ~30% is absorbed by the Aconcagua-FTB. Finally, we combine these findings with published geological data on the structure of the eastern back-arc Andean mountain front, and build a crustal-scale cross-section of the entire Andes at 33.5° S. We estimate a total orogenic shortening of ~31-55km, mainly absorbed by crustal west-vergent structures synthetic to the subduction. Our results provide quantitative key geological inferences to revisit this subduction-type orogeny and compare it to collisional alpine-type orogenic belts.
    Print ISSN: 0278-7407
    Electronic ISSN: 1944-9194
    Topics: Geosciences
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  • 8
    Publication Date: 2018-03-09
    Description: The continental margin of Southeast Asia evolved from a dominantly Andean - type active margin during Mesozoic to a Western Pacific - type since Late Cretaceous. With the spreading of the South China Sea, the Palawan - Mindoro Block drifted from mainland Asia and the Cenozoic strata provide an excellent window to gain insights into the tectonic evolution of the margin of Southeast Asia. Here we present U - Pb age and Hf isotopic data on detrital zircon grains from Cenozoic sedimentary rocks in the Palawan - Mindoro Block, the Philippines to evaluate the provenance and tectonic evolution of the South China Sea. Zircon grains in Eocene - Miocene sedimentary rocks from the Palawan - Mindoro Block show a wide range in age from 60 to 2700 Ma, with four major age groups of 80 - 120 Ma, 160 - 180 Ma, 1600 - 2100 Ma and 2200 - 2700 Ma. The εHf(t) of the zircon grains of the samples from Mindoro Island range from −39 to +13.7 and similar Hf isotopic composition is recorded in Paleogene and Neogene strata. Zircon U - Pb ages and Hf isotopic data of the Eocene samples from the Palawan - Mindoro Block show a similar pattern with those from Taiwan, which suggests that the Palawan - Mindoro Block was attached to the margin of South China during Late Cretaceous - Eocene times. The difference of zircon U - Pb age composition in the Miocene samples between the Palawan - Mindoro Block and Taiwan reflects southward drifting of the Palawan - Mindoro Block and seafloor spreading of the South China Sea at that time.
    Print ISSN: 0278-7407
    Electronic ISSN: 1944-9194
    Topics: Geosciences
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  • 9
    Publication Date: 2018-03-12
    Description: Management of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), an invasive, agricultural pest in the United States, has presented significant challenges. This polyphagous insect uses both extra-oral and gut-based digestion thwarting protein- or nucleotide-based control strategies. The objective of this study was to biochemically characterize the digestive enzymes (proteases and nucleases) from the saliva, salivary gland and the gut of H. halys . Enzyme profiles for the two tissues and saliva radically differ: The pH optimum for proteases in the gut was six, with cysteine proteases predominant. In contrast, the alkaline pH optima for protease activity in the salivary gland (8–10) and saliva (7) reflected abundant serine protease and cathepsin activities. RNase enzymes were most abundant in saliva, while dsRNase and DNase activities were higher in the salivary gland and saliva compared to those in the gut. These very different enzyme profiles highlight the biphasic digestive system used by this invasive species for efficient processing of plant nutrients. Knowledge of H. halys digestive physiology will allow for counteractive measures targeting digestive enzymes or for appropriate protection of protein- or nucleotide-based management options targeting this pest.
    Print ISSN: 0739-4462
    Electronic ISSN: 1520-6327
    Topics: Biology
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  • 10
    Publication Date: 2018-03-12
    Description: Cells and tissues are continuously exposed to a changing microenvironment, hence the necessity of a flexible modulation of gene expression that in complex organism have been achieved through specialized chromatin mechanisms. Chromatin-based cell memory enables cells to maintain their identity by fixing lineage specific transcriptional programs, ensuring their faithful transmission through cell division; in particular PcG-based memory system evolved to maintain the silenced state of developmental and cell cycle genes. In evolution the complexity of this system have increased, particularly in vertebrates, indicating combinatorial and dynamic properties of Polycomb proteins, in some cases even overflowing outside the cell nucleus. Therefore, their function may not be limited to the imposition of rigid states of genetic programs, but on the ability to recognize signals and allow plastic transcriptional changes in response to different stimuli. Here, we discuss the most novel PcG mediated memory functions in facing and responding to the challenges posed by a fluctuating environment. Cellular microenvironment can regularly change, hence the need for a dynamic modulation of transcriptional programs by the epigenome. In the current review, we highlight novel emerging aspects of epigenetic memory controlled by PcG proteins and the evolution of specialized functions to convey plasticity and adaptability to environmental changes.
    Print ISSN: 0265-9247
    Electronic ISSN: 1521-1878
    Topics: Biology , Medicine
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  • 11
    Publication Date: 2018-03-12
    Description: Centrosomes are the main microtubule organizing centers in animal cells. In particular during embryogenesis, they ensure faithful spindle formation and proper cell divisions. As metazoan centrosomes are eliminated during oogenesis, they have to be reassembled upon fertilization. Most metazoans use the sperm centrioles as templates for new centrosome biogenesis while the egg's cytoplasm re-prepares all components for on-going centrosome duplication in rapidly dividing embryonic cells. We discuss our knowledge and the experimental challenges to analyze zygotic centrosome reformation, which requires genetic experiments to enable scrutinizing respective male and female contributions. Male and female knockout animals and mRNA injection to mimic maternal expression of centrosomal proteins could point a way to the systematic molecular dissection of the process. The most recent data suggest that timely expression of centrosome components in oocytes is the key to zygotic centrosome reformation that uses male sperm as coordinators for de novo centrosome production. Centrosome reformation at fertilization is essential for metazoan development. It requires a complicated interplay of sperm centrioles and the cytoplasm of the oocyte, which has eliminated its centrioles during oogenesis. The male centrioles launch centrosome duplication using female centrosome proteins for the first metazoan cell divisions.
    Print ISSN: 0265-9247
    Electronic ISSN: 1521-1878
    Topics: Biology , Medicine
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  • 12
    Publication Date: 2018-03-12
    Description: It is generally accepted that insulin exerts an antiapoptotic effect against ischemia/reperfusion through the activation of PI3K/Akt/mTOR pathway. MicroRNAs involve in multiple cardiac pathophysiological processes, including ischemia/reperfusion–induced cardiac injury. However, the regulation of microRNAs in the cardioprotective effect of insulin is rarely discussed. In this study, using a cell model of ischemia through culturing H9C2 cardiac myocytes in serum-free medium with hypoxia, we demonstrated that pretreatment with insulin significantly inhibited cell apoptosis and downregulated microRNA-320 (miR-320) expression. Interestingly, miR-320 mimic impaired the cardioprotective effect of insulin against myocardial ischemia injury by targeting survivin, which is a member of the family of inhibitor of apoptosis proteins. Suppression miR-320 expression by miR-320 inhibitor in H9C2 cells with myocardial ischemia mimics the cardioprotective effect of insulin by maintaining survivin expression. Taken together, miR-320–mediated survivin expression involves in cardioprotective effect of insulin against myocardial ischemia injury. Significance of this study Myocardial ischemia/reperfusion (I/R) injury remains an important clinical problem with extremely deficient clinical therapies. Insulin exerts an antiapoptotic effect against I/R through the activation of PI3K/Akt/mTOR pathway. Here, we provided evidences to show that microRNA-320 involves in the cardioprotective effect of insulin by targeting survivin, which is an inhibitor of apoptosis protein and functions as a key regulator in cell apoptosis and involves in the tumour genesis and progression. Our findings may provide a new potential therapeutic strategy for I/R injury and ischemic heart disease.
    Print ISSN: 0263-6484
    Electronic ISSN: 1099-0844
    Topics: Biology , Medicine
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  • 13
    Publication Date: 2018-03-12
    Description: Ongoing controversy over logging the ancient Białowieża Forest in Poland symbolizes a global problem for policies and management of the increasing proportion of the earth's intact forest that is subject to post-disturbance logging. We review the extent of, and motivations for, post-disturbance logging in protected and unprotected forests globally. An unprecedented level of logging in protected areas and other places where green-tree harvest would not normally occur is driven by economic interests and a desire for pest control. To avoid failure of global initiatives dedicated to reducing the loss of species, five key policy reforms are necessary: (1) salvage logging must be banned from protected areas; (2) forest planning should address altered disturbance regimes for all intact forests to ensure that significant areas remain undisturbed by logging; (3) new kinds of integrated analyses are needed to assess the potential economic benefits of salvage logging against its ecological, economic, and social costs; (4) global and regional maps of natural disturbance regimes should be created to guide better spatio-temporal planning of protected areas and undisturbed forests outside reserves; and (5) improved education and communication programs are needed to correct widely-held misconceptions about natural disturbances. This article is protected by copyright. All rights reserved
    Print ISSN: 1755-263X
    Electronic ISSN: 1755-263X
    Topics: Biology
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  • 14
    Publication Date: 2018-03-12
    Description: Reconstructions of the carbonate compensation depth (CCD) in the past have been used to inform hypotheses about the nature of weathering, tectonics, climate change, and the major ion content of the world's oceans over the Cenozoic. These reconstructions are sensitive to uncertainties in the input data, in particular, the paleodepth estimates of sediment cores. Here we propose that a significant, previously unconsidered contributor to uncertainties in paleodepth estimates is from dynamic topography produced by radial stresses exerted on the Earth's surface by the convecting mantle; these stresses can warp the ocean floor by hundreds of meters over broad regions and also vary significantly over millions of years. We present new reconstructions of the equatorial Pacific and Indian Ocean CCDs over the last 30 Myr and 23 Myr, respectively, which demonstrate an overall deepening trend since the Miocene, and illustrate the possible effect of long-term changes in dynamic topography on these reconstructions.
    Electronic ISSN: 1525-2027
    Topics: Chemistry and Pharmacology , Geosciences , Physics
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  • 15
    Publication Date: 2018-03-12
    Description: A spherical harmonic model of the magnetic field of Jupiter is obtained from vector magnetic field observations acquired by the Juno spacecraft during its first 9 polar orbits about the planet. Observations acquired during 8 of these orbits provide the first truly global coverage of Jupiter's magnetic field with a coarse longitudinal separation of ~45 degrees between perijoves. The magnetic field is represented with a degree 20 spherical harmonic model for the planetary (“internal”) field, combined with a simple model of the magnetodisc for the field (“external”) due to distributed magnetospheric currents. Partial solution of the underdetermined inverse problem using generalized inverse techniques yields a model (“JRM09”) of the planetary magnetic field with spherical harmonic coefficients well determined through degree and order 10, providing the first detailed view of a planetary dynamo beyond Earth's.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
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  • 16
    Publication Date: 2018-03-12
    Description: El Nino events are characterized by anomalously warm tropical Pacific surface waters and concurrent ocean heat discharge, a precursor of subsequent cold La Nina conditions. Here we show that El Nino 2015/16 departed from this norm: despite extreme peak surface temperatures, Tropical Pacific (30N-30S) upper ocean heat content (OHC) increased by 9.6±1.7 ZJ (1ZJ=10 21 J), in stark contrast to the previous strong El Nino in 1997/98 (-11.5±2.9 ZJ). Unprecedented reduction of Indonesian Throughflow volume and heat transport played a key role in the anomalous 2015/16 event. We argue that this anomaly is linked with the previously documented intensified warming and associated rising sea levels in the Indian Ocean during the last decade. Additionally, increased absorption of solar radiation acted to dampen Pacific OHC discharge. These results explain the weak and short-lived La Nina conditions in 2016/17 and indicate the need for realistic representation of Indo-Pacific energy transfers for skilful seasonal-to-decadal predictions.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
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  • 17
    Publication Date: 2018-03-12
    Description: microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression post-transcriptionally by interfering with the translation of one or more target mRNAs. The unique miRNA sequences are involved in many physiological and pathological processes. Dysregulation of miRNAs contributes to the pathogenesis of all types of cancer. Notably, the diminished expression of tumor suppressor miRNAs, such as members of the Let-7 and miR-34 family, promotes tumor progression, invasion and metastasis. The past lustrum in particular, has witnessed substantial improvement of miRNA replacement therapy. This approach aims to restore tumor suppressor miRNA function in tumor cells using synthetic miRNA mimics or miRNA expression plasmids. Here, we provide a comprehensive review of recent advances in miRNA replacement therapy for treatment of cancer and its advantages over conventional gene therapy. We discuss a wide variety of delivery methods and vectors, as well as obstacles that remain to be overcome. Lastly, we review efforts to reverse epigenetic alterations, which affect miRNA expression in cancer cells, and the promising observation that restoring miRNA function re-sensitizes resistant tumor cells to chemotherapeutic drugs. The fact that various miRNA replacement therapies are currently in clinical trial demonstrates the great potential of this approach to treat cancer. Recent advances in microRNA replacement therapy in cancers.
    Electronic ISSN: 1097-4652
    Topics: Biology , Medicine
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  • 18
    Publication Date: 2018-03-12
    Description: The experimental dataset of downwelling radiance spectra measured at the ground in clear conditions during 2013 by a Far Infrared Fourier Transform Spectrometer at Dome-C, Antarctica, presented in Rizzi et al. [2016] is used to estimate the effect of solar heating of the radiosonde humidity sensor, called dry bias. The effect is quite evident comparing residuals for the Austral Summer and Winter clear cases and can be modeled by an increase of the water vapour concentration at all levels by about15%. Such an estimate has become possible only after a new version of the simulation code and spectroscopic data has become available, which has substantially improved the modelling of water vapour absorption in the Far Infrared. The negative yearly spectral bias reported in Rizzi et al. [2016] is in fact greatly reduced when compared to the same measurement dataset.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
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  • 19
    Publication Date: 2018-03-12
    Description: A spectral analysis of daily rainfall data has been performed to investigate extreme rainfall events in South China during the presummer rainy seasons between 1998-2015 (excluding 1999, 2006, 2011 and 2014). The results reveal a dominant frequency mode at the synoptic scale with pronounced positive rainfall anomalies. By analyzing the synoptic-scale bandpass-filtered anomalous circulations, 24 extreme rainfall episodes (defined as those with a daily rainfall amount in the top 5%) are categorized into “cyclone” (15) and “trough” (8) types, with the remaining events as an “anticyclone” type, according to the the primary anomalous weather system contributing to each extreme rainfall episode. The 15 cyclone-type episodes are further separated into (11) lower- and (4) upper-tropospheric migratory anomalies. An analysis of their anomalous fields shows that both types could be traced back to the generation of cyclonic anomalies downstream of the Tibetan Plateau, except for two episodes of lower-tropospheric migratory anomalies originating over the South China Sea. However, a lower-tropospheric cyclonic anomaly appears during all phases in the former type, but only in the wettest phase in the latter type, with its peak disturbance occurring immediately beneath an upper-level warm anomaly. The production of extreme rainfall in the trough-type episodes is closely related to a deep trough anomaly extending from an intense cyclonic anomaly over North China, which in turn could be traced back to a mid-latitude Rossby-wave train passing by the Tibetan Plateau. The results have important implications for understanding the origin, structure, and evolution of synoptic disturbances associated with the pre-summer extreme rainfall in South China.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
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  • 20
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    Wiley-Blackwell
    Publication Date: 2018-03-12
    Description: No abstract is available for this article.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
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  • 21
    Publication Date: 2018-03-12
    Description: The changing material composition of cars represents a challenge for future recycling of end-of-life vehicles (ELVs). Particularly, as current recycling targets are based solely on mass, critical metals increasingly used in cars might be lost during recycling processes, due to their small mass compared to bulk metals such as Fe and Al. We investigate a complementary indicator to material value in passenger vehicles based on exergy. The indicator is called thermodynamic rarity and represents the exergy cost (GJ) needed for producing a given material from bare rock to the market. According to our results, the thermodynamic rarity of critical metals used in cars, in most cases, supersedes that of the bulk metals that are the current focus of ELV recycling. While Fe, Al, and Cu account for more than 90% of the car's metal content, they only represent 60% of the total rarity of a car. In contrast, while Mo, Co, Nb, and Ni account for less than 1% of the car's metal content, their contribution to the car's rarity is larger than 7%. Rarity increases with the electrification level due to the greater amount of critical metals used; specifically, due to an increased use of (1) Al alloys are mainly used in the car's body-in-white of electric cars for light-weighting purposes, (2) Cu in car electronics, and (3) Co, Li, Ni, and rare earth metals (La, Nd, and Pr) in Li-ion and NiMH batteries.
    Print ISSN: 1088-1980
    Electronic ISSN: 1530-9290
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 22
    Publication Date: 2018-03-12
    Description: Now-a-days, plant species are consumed globally for various purposes and this increasing demand leads to adulteration due to gradually exploitation in natural resources. The major causes of adulteration may be confusion in nomenclature, unawareness of authentic sources, unavailability of authentic sources, color resemblances, deficiencies in collection procedures, and misidentification. This study aims to use the microscopic techniques such as scanning electron microscopy for the authentication of the oil yielding seeds of four important and traditionally used species Prunus persica , Prunus domestica , and Eruca sativa and Argemone Mexicana from their adulterants. All of these are versatile in usage. Locally, these four plants are adulterated badly and there is need to provide a criteria and a complete monograph for correct identification. This research may prove to be helpful for quality control and as well for future studies to explore other novel aspects of these plants. Scanning electron microscopy (SEM) is applied for discrimination of morphologically similar oil yielding seeds SEM can be used for quality control of seeds Seed surface ornamentation is found to be in authentication of original source of seeds
    Print ISSN: 1059-910X
    Electronic ISSN: 1097-0029
    Topics: Natural Sciences in General
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  • 23
    Publication Date: 2018-03-12
    Description: Reconstructing past changes in the spatial structure of tropical Pacific hydroclimate requires archives of past moisture balance across spatial gradients of precipitation. To date, only one, 600-year, terrestrial record of hydroclimate is available for the central tropical Pacific (CTP) from Washington Lake, Washington Island, limiting the ability to test hypotheses regarding the location of the CTP Intertropical Convergence Zone (ITCZ) in the last millennium. A new lake sediment record from Lake 30, Kiritimati, Republic of Kiribati, 3° south of Washington Island, provides additional constraints on past CTP ITCZ position. Lake 30 geochemical and sedimentological data indicate an episode of increased microbial mat development and gypsum precipitation from 900 to 1200 C.E., coincident with the Medieval Climate Anomaly (MCA). We infer drier conditions during the MCA at Kiritimati as the Washington Lake proxy record indicates wetter conditions, suggesting the CTP ITCZ was displaced northward during the MCA relative to its position today. At the transition between the MCA and the Little Ice Age (LIA), Lake 30 sediment becomes predominantly carbonate, suggesting a transition to wetter conditions and a southward shift of the ITCZ relative to its MCA position. However, a tropical Pacific synthesis of hydroclimate-sensitive proxy records does not point to a consistent spatial or temporal pattern of variability in the MCA and LIA, suggesting multiple influences on centennial-scale tropical Pacific hydroclimate during the last millennium.
    Print ISSN: 0883-8305
    Electronic ISSN: 1944-9186
    Topics: Geosciences
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  • 24
    Publication Date: 2018-03-13
    Description: Honey bees require nectar and pollen from flowers: nectar for energy and pollen for growth. The demand for nectar and pollen varies during the year, with more pollen needed in spring for colony population growth, and more nectar needed in summer to sustain the maximum colony size and collect surplus nectar stores for winter. Sufficient bee forage is therefore necessary to ensure a healthy bee colony. Land-use changes can reduce the availability of floral resources suitable for bees, thereby increasing the susceptibility of bees to other stressors such as disease and pesticides. In contrast, land-based management decisions to protect or plant bee forage can enhance pollen and nectar supply to bees while meeting other goals such as riparian planting for water-quality improvement. Commercial demand for honey can also put pressure on floral resources through over-crowding of hives. To help understand and manage floral resources for bees, we developed a spatial model for mapping monthly nectar and pollen production from maps of land cover. Based on monthly estimated production data we mapped potential monthly supply of nectar and pollen to a given apiary location in the landscape. This is done by summing the total production within the foraging range of the apiary while subtracting the estimated nectar converted to energy for collection. Ratios of estimated supply over theoretical hive demand may then be used to infer a potential landscape carrying capacity to sustain hives. This model framework is quantitative and spatial, utilising estimated flight energy costs for nectar foraging. It can contribute to management decisions such as where apiaries could be placed in the landscape depending on floral resources and where nectar limited areas may be located. It can contribute to planning areas for bee protection or planting such as in riparian vegetation. This would aid managed bee health, wild pollinator protection and honey production. We demonstrate the methods in a case study in New Zealand where there is a growing demand for mānuka ( Leptospermum scoparium ) honey production. This article is protected by copyright. All rights reserved.
    Print ISSN: 1051-0761
    Electronic ISSN: 1939-5582
    Topics: Biology
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  • 25
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    Wiley-Blackwell
    In: Ecology
    Publication Date: 2018-03-13
    Print ISSN: 0012-9658
    Electronic ISSN: 1939-9170
    Topics: Biology
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  • 26
    Publication Date: 2018-03-13
    Description: It is not new to recognise that data from remote sensing platforms is transforming the way we characterise and analyse our environment. The ability to collect continuous data spanning spatial scales now allows geomorphological research in a data rich environment and this special issue (coming just 7 years after the 2010 special issue of ESPL associated with the remote sensing of rivers) highlights the considerable research effort being made to exploit this information, into new understanding of geomorphic form and process. The 2010 special issue on the remote sensing of rivers noted that fluvial remote sensing papers made up some 14% of the total river related papers in ESPL. A similar review of the papers up to 2017 reveals that this figure has increased to around 25% with a recent proliferation of articles utilising satellite based data and structure from motion derived data. It is interesting to note, however that many studies published to date are proof of concept, concentrating on confirming the accuracy of the remotely sensed data at the expense of generating new insights and ideas on fluvial form and function. Data is becoming ever more accurate and researchers should now be concentrating on analysing these early data sets to develop increased geomorphic insight challenging paradigms and moving the science forward. The prospect of this occurring is increased by the fact that many of the new remote sensed platforms allow accurate spatial data to be collected cheaply and efficiently. This is providing the individual researcher or small research grouping with tremendous opportunity to move the science of fluvial geomorphology forward unconstrained to a large degree of the need to secure substantial research funding. Fluvial geomorphologists have never before been in such a liberated position! As techniques and analytical skills continue to improve it is inevitable that Marcus and Fondstad's (2010) prediction that remotely sensed data will revolutionising our understanding of geomorphological form and process will prove true, altering our ideas on the very nature of system functioning in the process.
    Print ISSN: 0197-9337
    Electronic ISSN: 1096-9837
    Topics: Geography , Geosciences
    Published by Wiley-Blackwell
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  • 27
    Publication Date: 2018-03-13
    Description: Enchytraeus albidus is a terrestrial earthworm widespread along the coasts of northern Europe and the Arctic. This species tolerates freezing of body fluids and survives winters in a frozen state. Their acclimatory physiological mechanisms behind freeze tolerance involve increased fluidity of membrane lipids during cold exposure and accumulation of cryoprotectants (glucose) during the freezing process. Gene regulatory processes of these physiological responses have not been studied, partly because no gene expression tools were developed. The main aim of this study was to understand whether the freeze tolerance mechanisms have a transcriptomic basis in E. albidus . For that purpose, first the transcriptome of E. albidus was assembled with RNAseq data. Second, two strains from contrasting thermal environments (Germany and Greenland) were compared by mapping barcoded RNAseq data onto the assembled transcriptome. Both of these strains are freeze tolerant, but Greenland is extremely freeze tolerant. Results showed more plastic responses in the Greenland strain as well as higher constitutive expression of particular stress response genes. These altered transcriptional networks are associated with an adapted homeostasis coping with prolonged freezing conditions in Greenland animals. Previously identified physiological alterations in freeze-tolerant strains of E. albidus are underpinned at the transcriptome level. These processes involve anion transport in the hemolymph, fatty acid metabolism, metabolism, and transport of cryoprotective sugars as well as protection against oxidative stress. Pathway analysis supported most of these processes, and identified additional differentially expressed pathways such as peroxisome and Toll-like receptor signaling. We propose that the freeze-tolerant phenotype is the consequence of genetic adaptation to cold stress and may have driven evolutionary divergence of the two strains. We studied transcriptional regulatory networks underlying cold tolerance in a natural Enchytraeus albidus population from Greenland as compared to a freeze-sensitive reference population. Constitutive overexpression of stress response genes as well as increased transcriptional plasticity of genes involved in cold tolerance-associated physiological processes seem to have shaped genetic adaptation to prolonged freezing conditions.
    Electronic ISSN: 2045-7758
    Topics: Biology
    Published by Wiley-Blackwell
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  • 28
    Publication Date: 2018-03-13
    Description: With wildlife populations in decline, understanding their distributions across the landscape are needed for management and conservation efforts, particularly in remote or hazardous regions. We used indigenous local knowledge to inform species distribution models (SDMs) to predict the distribution of 38 wildlife species historically documented in Somaliland, one of the most isolated, data-poor regions in Africa. We conducted 195 interviews with agro-pastoral men and women in 2016 and 2017 throughout Somaliland based on the environmental range captured by performing a Multivariate Environmental Similarity Surface (MESS) analysis. Respondents were asked if each species (1) occurred in the vicinity, and if they did, (2) whether it was common, rare, extirpated, or unknown. We tested two commonly used SDMs, Maxent and boosted regression trees (BRTs), to map the potential distribution of wildlife using interview data. We present detailed case studies of two species of high conservation priority: cheetah ( Acinonyc jubatus ) and African wild ass ( Equus africanus somaliensis ). More than half of the respondents reported the presence of 25 of the wildlife species in the survey. Additionally, we developed Maxent models for all surveyed wildlife known to develop a species richness map. The least reported species known to have inhabited Somaliland in recent decades were lion ( Panthera leo ), African wild ass, and Somali wild dog ( Lycaon pictus somalicus ). Surprisingly, 177 of respondents reported the presence of cheetah, which was presumed by many to be extirpated from Somaliland. Given the high number of reports, coupled with the BRT model results and evaluations, it may be that cheetahs persist throughout Somaliland. Unfortunately, our results also suggest that African wild ass may have been extirpated from Somaliland. Our models carry the uncertainties of the raw data, but provide habitat suitability maps to guide future targeted surveys. Our methods and results demonstrate that integrating indigenous local knowledge with SDMs may be an essential tool for the conservation of wildlife in data-poor regions.
    Electronic ISSN: 2150-8925
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 29
    Publication Date: 2018-03-13
    Description: Ecologists have been interested in understanding communities through the lens of specialists and generalists to predict species diversity and distribution patterns and to ameliorate worldwide declines in specialist species. Dispersal traits are assumed to be associated with specialization (specialists are weaker dispersers than generalists), but dispersal modes can be variable within groups. Niche-based predictions of occupancy and environmental responses were assessed using invertebrates from California vernal pools that were categorized by specialization (endemic or widespread taxa) and dispersal mode (passive or active dispersal). Data from a latitudinal gradient resulted in widespread taxa with greater percent occupancy than endemic taxa as predicted, but passive dispersers had greater occupancy than active dispersers in contrast to predictions. Endemic species and widespread-active dispersers exhibited similar levels of specialization measured as coefficient of variation among treatments in a mesocosm experiment. This suggested that habitat choice was important, and these differences in specialization were scale dependent (generalists across habitat types and specialists within a habitat type). A negative correlation between latitudinal occupancy and level of specialization demonstrated how local-scale responses and landscape patterns were related and depend on both specialization and dispersal traits. This study underscores how habitat heterogeneity and species traits, including specialization and dispersal, can interact to affect community patterns at different spatial scales.
    Electronic ISSN: 2150-8925
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 30
    Publication Date: 2018-03-13
    Description: Skillful predictions of continental climate would be of great practical benefit for society and stakeholders. It nevertheless remains fundamentally unresolved to what extent climate is predictable, for what features, at what time scales, and by which mechanisms. Here we identify the dominant time scales and sources of European surface air temperature (SAT) variability during the cold season using a coupled climate reanalysis, and a statistical method that estimates SAT variability due to atmospheric circulation anomalies. We find that eastern Europe is dominated by sub-decadal SAT variability associated with the North Atlantic Oscillation, whereas interdecadal and multi-decadal SAT variability over northern and southern Europe are thermodynamically driven by ocean temperature anomalies. Our results provide evidence that temperature anomalies in the North Atlantic Ocean are advected over land by the mean westerly winds, and, hence, provide a mechanism through which ocean temperature controls the variability and provides predictability of European SAT.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
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  • 31
    Publication Date: 2018-03-13
    Description: Future projections of east Amazonian precipitation indicate drying, but they are uncertain and poorly understood. In this study we analyse the Amazonian precipitation response to individual atmospheric forcings using a number of global climate models. Black carbon is found to drive reduced precipitation over the Amazon due to temperature-driven circulation changes, but the magnitude is uncertain. CO 2 drives reductions in precipitation concentrated in the east, mainly due to a robustly negative, but highly variable in magnitude, fast response. We find that the physiological effect of CO 2 on plant stomata is the dominant driver of the fast response due to reduced latent heating, and also contributes to the large model spread. Using a simple model we show that CO 2 physiological effects dominate future multi-model mean precipitation projections over the Amazon. However, in individual models temperature-driven changes can be large, but due to little agreement, they largely cancel out in the model-mean.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
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  • 32
    Publication Date: 2018-03-13
    Description: Climate models show a robust negative feedback in the midlatitudes, coincident with an increase in cloud liquid in the mixed-phase region of the control climate. This 'mixed-phase feedback' is normally attributed to a feedback caused by a phase-change feedback (ice to liquid). Here we use an aquaplanet configuration to investigate this in more detail. We use high-frequency instantaneous diagnostics and composite them in ascending and descending regimes. We find that a large fraction of the increase in cloud liquid water in the mixed-phase region does not significantly contribute to the radiative feedback due to a masking effect of the ice cloud above. Using some simple arguments and approximate calculations, we estimate that about one-third of the total shortwave negative radiative feedback is driven by a phase-change feedback, whereas the rest of the feedback is driven by changes in ice and warm liquid clouds.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
    Topics: Geosciences , Physics
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  • 33
    Publication Date: 2018-03-13
    Description: Hadal trenches have been proposed as depocenters of organic material and hotspots for organic matter mineralization. In this study, we for the first time quantified the total benthic O 2 uptake in hadal trenches using in-situ chamber incubations. Three trenches in the tropical Pacific were targeted and exhibited relatively high diagenetic activity given the great water depths, i.e., the Mariana Trench (2.0×10 2 μmol O 2 m -2 d -1 , 10,853 m), the Mussau Trench (2.7±0.1×10 2 μmol O 2 m -2 d -1 , 7,011 m), and the New Britain Trench (6.0±0.1×10 2 μmol O 2 m -2 d -1 , 8,225 m). Combined with the analyses of total organic carbon (TOC) and δ 13 C of TOC in the sediments and previously published in-situ O 2 microprofiles from hadal settings, we suggest that hadal benthic carbon mineralization partly is governed by the surface production but also is linked to the distance from land. Therefore, we highlight that terrestrial organic matter can be of importance in sustaining benthic communities in some hadal settings.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
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  • 34
    Publication Date: 2018-03-13
    Description: To assess phytoplankton nutritional status in seasonally oligotrophic waters of the southern Mid-Atlantic Bight, and the potential for rain to stimulate primary production in this region during summer, shipboard bioassay experiments were performed using natural seawater and phytoplankton collected north and south of the Gulf Stream. Bioassay treatments comprised iron, nitrate, iron+nitrate, iron+nitrate+phosphate, and rainwater. Phytoplankton growth was inferred from changes in chlorophyll- a , inorganic nitrogen and carbon-13 uptake, relative to unamended control treatments. Results indicated the greatest growth stimulation by iron+nitrate+phosphate, intermediate growth stimulation by rainwater, modest growth stimulation by nitrate and iron+nitrate, and no growth stimulation by iron. Based on these data and analysis of seawater and atmospheric samples, nitrogen was the proximate limiting nutrient, with a secondary limitation imposed by phosphorus. Our results imply that summer rain events increase new production in these waters by contributing nitrogen and phosphorus, with the availability of the latter setting the upper limit on rain-stimulated new production.
    Print ISSN: 0094-8276
    Electronic ISSN: 1944-8007
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  • 35
    Publication Date: 2018-03-13
    Description: Molybdenum disulfide (MoS 2 ), a type of transition metal dichalcogenide material, has emerged as an important class among 2D systems. When 2D MoS 2 materials are reduced to 0D quantum dots (QDs), they introduce new optical properties that point to several potential technological advantages in electronic, magnetic, optical, and catalytic properties. In this study, a simple way to produce chiral MoS 2 QDs from MoS 2 nanopowder is presented using l (+)-ascorbic acid as a reducing agent. The calculated quantum yield of QDs is 11.06%. Experimental results reveal that the size of QDs is uniformly monodispersed (2–3 nm) and have a blue emissive fluorescence peak and circular dichroism (CD) peak located at 420 and 330 nm, respectively. Furthermore, a dual-mode detection system based on fluorescence and chirality is performed using as-synthesized MoS 2 QDs, where QDs are conjugated with anti-hemagglutinin antibodies of avian influenza virus and made into an immunobridge in the presence of target virus and anti-neuraminidase antibodies conjugated magnetic nanoparticles (MNPs). The photoluminescence and CD spectra of unconjugated QDs after separated magnetochirofluorescent (MNPs-QDs) nanohybrids by external magnets enables influenza virus A (H5N1) detection with the limit of detection value of 7.35 and 80.92 pg mL −1 , respectively. A dual-mode biosensing detection system based on fluorescence and chirality of MoS 2 quantum dots for avian influenza viruses is described.
    Electronic ISSN: 2056-6646
    Topics: General, Interdisciplinary , Energy, Environment Protection, Nuclear Power Engineering
    Published by Wiley-Blackwell
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  • 36
    Publication Date: 2018-03-13
    Description: We report the formation of Al 2 O 3 -SiO 2 fiber-reinforced Al 2 O 3 -SiO 2 aerogels with the content of fibers in the range from 40 wt% to 55 wt% by sol-gel reaction, followed by supercritical drying. The structure and physical properties of fiber-reinforced Al 2 O 3 -SiO 2 aerogels are studied. We find that the fiber-reinforced Al 2 O 3 -SiO 2 aerogels can be resistant to the temperature of 1200 °C. The integration of fibers significantly improves the mechanical properties of Al 2 O 3 -SiO 2 aerogels. We find that the bending strength of fiber-reinforced Al 2 O 3 -SiO 2 aerogels increases 0.431MPa to 0.755 MPa and the elastic modulus increases from 0.679 MPa to 1.153 MPa, when the content of fibers increases from 40 wt% to 50 wt%. The thermal conductivity of the fiber-reinforced Al 2 O 3 -SiO 2 aerogels is in the range from 0.0403 W/mK to 0.0545 W/mK, depending on the content of fibers. This article is protected by copyright. All rights reserved.
    Print ISSN: 1546-542X
    Electronic ISSN: 1744-7402
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 37
    Publication Date: 2018-03-13
    Description: Oxidation protective SiC nanowires-reinforced SiC (SiCNWs-SiC) coating was prepared on pack cementation (PC) SiC coated carbon/carbon (C/C) composites by a simple chemical vapor deposition (CVD) process. This double-layer SiCNWs-SiC/PC SiC coating system on C/C composites not only has the advantages of SiC buffer layer, but also has the toughening effects of SiCNWs. The microstructure and phase composition of the nanowires and the coatings were examined by SEM, TEM and XRD. The single-crystalline β-SiC nanowires with twins and stacking faults were deposited uniformly and oriented randomly with diameter of 50-200 nm and length ranging from several to tens micrometers. The dense SiCNWs-SiC coating with some closed pores was obtained by SiC nanocrystals stacked tightly with each other on the surface of SiCNWs. After introducing SiCNWs in the coating system, the oxidation resistance is effectively improved. The oxidation test results showed that the weight loss of the SiCNWs-SiC/PC SiC coated samples were 4.91% and 1.61% after oxidation at 1073 K for 8 h and at 1473 K for 276 h, respectively. No matter oxidation at which temperature, the SiCNWs-SiC/PC SiC coating system has better antioxidation property than the single-layer PC SiC coating or the double-layer CVD SiC/PC SiC coating without SiCNWs. This article is protected by copyright. All rights reserved.
    Print ISSN: 1546-542X
    Electronic ISSN: 1744-7402
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 38
    Publication Date: 2018-03-13
    Description: A rapidly developing area of ceramic science and technology involves research about the interactions between bioceramic materials and human body. Over the past half century, the use of bioceramics has revolutionized the surgical treatment of various diseases that primarily affect bone and teeth as well as many therapeutic approaches, thus contributing to significantly improve the quality of life of rehabilitated patients. Hydroxyapatite and other calcium phosphates have been largely employed in orthopaedics and dentistry for repairing small osseous defects since at least four decades. This article is protected by copyright. All rights reserved.
    Print ISSN: 1546-542X
    Electronic ISSN: 1744-7402
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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  • 39
    Publication Date: 2018-03-13
    Description: Precipitation is an important climate quantity that is critically relevant to society. In spite of intense efforts, significant precipitation biases remain in most climate models. One pervasive and persistent bias found in many general circulation models occurs in the Tropical West Pacific where northern hemisphere summer-time precipitation is often underestimated compared to observations. Using the DOE-E3SM model, the inclusion of a missing process, convective gustiness, is shown to reduce those biases through a net increase in surface evaporation. Gustiness in surface wind fields is assumed to arise empirically in proportion to the intensity of convective precipitation. The increased evaporation can be treated as an increase in the moist static energy forcing into the atmosphere. A Normalized Gross Moist Stability (NGMS) framework (which characterizes the relationship between convective forcing and convective response) is used to explore the processes responsible for the precipitation bias, and the impact of the gustiness parameterization in reducing that bias. Because the NGMS of the Tropical West Pacific is less than unity in the E3SMv1 model, the increase in energy forcing amplifies the increase in precipitation to exceed that of the evaporative flux. Convective gustiness favors increased precipitation in regions where the resolved surface winds are weak and convection is present.
    Electronic ISSN: 1942-2466
    Topics: Geography , Geosciences
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  • 40
    Publication Date: 2018-03-13
    Description: Characterizing the 700-km-wide system of active faults on the Shan Plateau, southeast of the eastern Himalayan syntaxis (EHS), is critical to understanding the geodynamics and seismic hazard of the large region that straddles neighboring China, Myanmar, Thailand, Laos and Vietnam. Here we evaluate the fault styles and slip rates over multi-timescales, reanalyze previously-published short-term GPS velocities and evaluate slip-rate gradients to interpret the regional kinematics and geodynamics that drive the crustal motion. Relative to the Sunda plate, GPS velocities across the Shan Plateau define a broad arcuate tongue-like crustal motion with a progressively northwestward increase in sinistral shear over a distance of ~700 km followed by a decrease over the final ~100 km to the syntaxis. The cumulative GPS slip rate across the entire sinistral-slip fault system on the Shan Plateau is ~12 mm/yr. Our observations of the fault geometry, slip rates and arcuate southwesterly-directed tongue-like patterns of GPS velocities across the region suggest that the fault kinematics is characterized by a regional southwestward distributed shear across the Shan Plateau, compared to more block-like rotation and indentation north of the Red River fault. The fault geometry, kinematics and regional GPS velocities are difficulty to reconcile with regional bookshelf faulting between the Red River and Sagaing faults or localized lower crustal channel flows beneath this region. The crustal motion and fault kinematics can be driven by a combination of basal traction of a clockwise, southwestward asthenospheric flow around the EHS and gravitation or shear-driven indentation from north of the Shan Plateau.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
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  • 41
    Publication Date: 2018-03-13
    Description: The ability to forecast ecological carbon cycling is imperative to land management in a world where past carbon fluxes are no longer a clear guide in the Anthropocene. However, carbon-flux forecasting has not been practiced routinely like numerical weather prediction. This study explored: (1) the relative contributions of model forcing data and parameters to uncertainty in forecasting flux- vs. pool-based carbon cycle variables; and (2) time points when temperature and CO 2 treatments may cause statistically detectable differences in those variables. We developed an online forecasting workflow (EcoPAD), which facilitates iterative data-model integration. EcoPAD automates data transfer from sensor networks, data assimilation and ecological forecasting. We used SPRUCE data collected from 2011-2014 to constrain the parameters in the Terrestrial ECOsystem Model (TECO), forecast carbon cycle responses to elevated CO 2 and a gradient of warming from 2015 to 2024, and specify uncertainties in the model output. Our results showed that data assimilation substantially reduces forecasting uncertainties. Interestingly, we found that the stochasticity of future external forcing contributed more to the uncertainty of forecasting future dynamics of C flux-related variables than model parameters. However, the parameter uncertainty primarily contributes to the uncertainty in forecasting C pool-related response variables. Given the uncertainties in forecasting carbon fluxes and pools, our analysis showed that statistically different responses of fast-turnover pools to various CO 2 and warming treatments were observed sooner than slow-turnover pools. Our study has identified the sources of uncertainties in model prediction and thus leads to improve ecological carbon cycling forecasts in the future.
    Print ISSN: 0148-0227
    Topics: Biology , Geosciences
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  • 42
    Publication Date: 2018-03-13
    Description: Water relations in plant communities are influenced both by contrasting functional groups (grasses, shrubs) and by climate change via complex effects on interception, uptake and transpiration. We modelled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate change on ecological drought (soil water potential below which photosynthesis stops) in 340 semiarid grassland sites over 30-year periods. Relative to control vegetation (climate and site-determined mixes of functional groups), the frequency and duration of drought were increased by shrubs and decreased by annual grasses. The rankings of shrubs, control vegetation, and annual grasses in terms of drought effects were generally consistent in current and future climates, suggesting that current differences among functional groups on drought effects predict future differences. Climate change accompanied by experimentally-increased biomass (i.e. the effects of invasions that increase community biomass, or management that increases productivity through fertilization or respite from grazing) increased drought frequency and duration, and advanced drought onset. Our results suggest that the replacement of perennial temperate semiarid grasslands by shrubs, or increased biomass, can increase ecological drought both in current and future climates.
    Print ISSN: 0148-0227
    Topics: Biology , Geosciences
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  • 43
    Publication Date: 2018-03-13
    Description: Dissolved hydrogen measurements were made at high resolution in surface waters along a tropical north Atlantic transect between Guadeloupe and Cape Verde in 2015 (Meteor 116). Parallel water samples acquired to assess the relative abundance of the nifH gene from several types of diazotrophs, indicated that Trichodesmium and UCYN-A were dominant in this region. We show that a high degree of correlation exists between the hydrogen saturations and UCYN- A nifH abundance, and a weak correlation with Trichodesmium . The findings suggest that nitrogen fixation by UCYN-A is a major contributor to hydrogen supersaturations in this region of the ocean. The ratio of hydrogen released to nitrogen fixed has not been determined for this symbiont, but the indications are that it may be high in comparison with the small number of diazotrophs for which the ratio has been measured in laboratory cultures. We speculate that this would be consistent with the diazotroph being an exosymbiont on its haptophyte host. Our high resolution measurements of hydrogen concentrations are capable of illustrating the time and space scales of inferred activity of diazotrophs in near real-time in a way that cannot be achieved by biological sampling and rate measurements requiring incubations with 15 N 2 . Direct measurement of high resolution spatial variability would be relatively challenging through collection and analysis of biological samples by qPCR, and extremely challenging by 15 N-uptake techniques, neither of which methods yields real-time data. Nonetheless, determination of fixation rates still firmly depends on the established procedure of incubations in the presence of 15 N 2 .
    Print ISSN: 0148-0227
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  • 44
    Publication Date: 2018-03-13
    Description: Oceanic magnetic signals are sensitive to ocean velocity, salinity, and heat content. The detection of respective signals with global satellite magnetometers would pose a very valuable source of information. While tidal magnetic fields are already detected, electromagnetic signals of the ocean circulation still remain unobserved from space. We propose to use satellite altimetry to construct proxy magnetic signals of the ocean circulation. These proxy time series could subsequently be fitted to satellite magnetometer data. The fitted data could be removed from the observations or the fitting constants could be analyzed for physical properties of the ocean, e.g., the heat budget. To test and evaluate this approach, synthetic true and proxy magnetic signals are derived from a global circulation model of the ocean. Both data sets are compared in dependence of location and time scale. We study and report when and where the proxy data describe the true signal sufficiently well. Correlations above 0.6 and explained variances of above 80% can be reported for large parts of the Antarctic ocean, thus explaining the major part of the global, sub-seasonal magnetic signal.
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  • 45
    Publication Date: 2018-03-13
    Description: Coral bleaching represents one of the main climate-change related threats to reef ecosystems. This research represents a methodological alternative for modeling this phenomenon, focused on assessing uncertainties and complexities with a low number of observations. To develop this model, intermittent reef monitoring data from the largest reef complex in the South Atlantic collected over nine summers between 2000 and 2014 were used with remote sensing data to construct and train a bleaching seasonal prediction model. The Bayesian approach was used to construct the network as it is suitable for hierarchically organizing local thermal variables and combining them with El Niño indicators from the preceding winter to generate accurate bleaching predictions for the coming season. Network count information from six environmental indicators was used to calculate the probability of bleaching, which is mainly influenced by the combined information of two thermal indices; one thermal index is designed to track short period anomalies in the early summer that are capable of triggering bleaching (SST of five consecutive days), and the other index is responsible for tracking the accumulation of thermal stress over time, an index called degree heating trimester (DHT). In addition to developing the network, this study conducted the three tests of applicability proposed for model: 1- Perform the forecast of coral bleaching for the summer of 2016; 2- Investigate the role of turbidity during the bleaching episodes; and 3- Use the model information to identify areas with a lower predisposition to bleaching events.
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  • 46
    Publication Date: 2018-03-13
    Description: Nishimura et al [2010, 2011, 2013 and in their comment, hereafter called N18] have suggested that chorus waves interact with equatorial electrons to produce pulsating auroras. We agree that chorus can scatter electrons 〉10 keV, as do Time Domain Structures (TDS). Lower energy electrons occurring in pulsating auroras cannot be produced by chorus but such electrons are scattered and accelerated by TDS. TDS often occur with chorus and have power in their spectra at chorus frequencies. Thus, the absence of power at low frequencies is not evidence that TDS are absent, as an example shows. Through examination of equatorial electric field waveforms and electron pitch angle distributions measured on the THEMIS satellites (in place of examining field and particle spectra, as done by Nishimura et al), we show that chorus cannot produce the field-aligned electrons associated with pulsating auroras in the Nishimura et al [2010] events, but Time Domain Structures can. Equatorial field-aligned electron distributions associated with pulsating auroras and created by TDS in the absence of chorus or any other wave at the equator are also shown.
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  • 47
    Publication Date: 2018-03-13
    Description: The magnetic aromaticity of 6-membered monoheterocycles containing Group 13 to 16 elements (C 5 H 5 X, where X = SiH, GeH, N, P, As, O + , S + , Se + ) was assessed by using 2 magnetic descriptors: the π -electron contribution to the out-of-plane component of the nucleus-independent chemical shifts (NICSzz, π ) and ring current strength. The results show that both descriptors lead to the same conclusion regarding magnetic aromaticity. However, they do not agree with the predictions obtained by isotropic NICS, which is a most commonly used method. Ring current strength and NICS π predict that benzene is the most aromatic molecule of the series, with an only slightly less aromatic pyridine. Additionally, aromaticity decreases when going down in the same group of the periodic system. The only exception is the pyrylium cation, which is predicted as the least aromatic species of this series. This work compares different methods based on nucleus-independent chemical shift (NICS) computations with ring current strengths analysis. This shows that out-of-plane component of the NICSs (NICS π ) is the unique, based on NICS descriptor, that lead to similar conclusions to those obtained by ring current strength computations.
    Print ISSN: 0894-3230
    Electronic ISSN: 1099-1395
    Topics: Chemistry and Pharmacology , Physics
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  • 48
    Publication Date: 2018-03-13
    Description: Microcystin is one of the most common toxins associated with freshwater harmful algal blooms, but little is known about microcystin fate in the aquatic environment. Laboratory wave tank experiments were performed to determine whether exchange of surface water and pore water (benthic exchange) removes and dilutes microcystin-LR (MC-LR) at environmentally relevant concentrations in coastal waters overlying permeable sediments. Over the 100 h experiment, 60% of MC-LR mass was removed due to interaction with sediment (via adsorption and/or biodegradation), while only 20% was removed in an experiment without sediment. The observed fate and transport of MC-LR in sediments was adequately described with a one-dimensional reactive transport model that uses an enhanced diffusion coefficient to represent benthic exchange of solutes. Numerical sensitivity studies showed that MC-LR removal increases with hydraulic conductivity of sediment and wave height and decreases with water depth. For MC-LR concentration at the WHO recreational guideline (20 ppb), sandy sediments can remove the equivalent MC-LR mass in 1 m of surface water under typical nearshore wave conditions within tens of hours. In open water at large depths above a silty bed, removal times are much longer (on the order of weeks). Wave-driven benthic exchange is therefore an important control on MC-LR fate in energetic coastal areas but not in deep or calm settings where sediment–water interactions are greatly reduced. The nearshore fate of algal toxins is important to human health and socioeconomic vitality, since recreational activities and direct human exposures are concentrated along coasts.
    Print ISSN: 0024-3590
    Electronic ISSN: 1939-5590
    Topics: Biology , Geosciences , Physics
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  • 49
    Publication Date: 2018-03-13
    Description: As the costs and regulatory barriers to new water supply development continue to rise, drought management strategies have begun to rely more heavily on temporary conservation measures. While these measures are effective, they often lead to intermittent and unpredictable reductions in revenues that are financially disruptive to water utilities, raising concerns over lower credit ratings and higher rates of borrowing for this capital intensive sector. Consequently, there is growing interest in financial risk management strategies that reduce utility vulnerabilities. This research explores the development of financial index insurance designed to compensate a utility for drought related losses. The focus is on analyzing candidate hydrologic indices that have the potential to be used by utilities across the U.S., increasing the potential for risk pooling, which would offer the possibility of both lower risk management costs and more widespread implementation. This work first analyzes drought-related financial risks for 315 publicly operated water utilities across the country and examines the effectiveness of financial contracts based on several indices both in terms of their correlation with utility revenues and their spatial autocorrelation across locations. Hydrologic-based index insurance contracts are then developed and tested over a 120-year period. Results indicate that risk pooling, even under conditions in which droughts are subject to some level of spatial autocorrelation, has the potential to significantly reduce the cost of managing financial risk.
    Print ISSN: 0043-1397
    Electronic ISSN: 1944-7973
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 50
    Publication Date: 2018-03-14
    Description: In a hydrogen network, sinks and sources are generally connected to reactors or purifiers, and their compositions and flow rates are affected by these equipments. The relationship between these streams deserves to be studied based on the integration of the hydrogen network to identify the feasible and optimal operating conditions of the reactors and purifiers. Equations are deduced to describe the quantitative relationship among the hydrogen consumption, the hydrogen concentration and flow rates of coupled sink and source, the purification feed and purified product. Based on this, the Δ F SKq ~ F pur quantitative diagram is plotted to identify the feasible region and the variation trend line. The purification and hydrogen consuming reactor parameters can be optimized in the design and operation stage of a hydrogen network. The case study shows that the proposed method is simple, easy understanding, and can be applied to identify the variation trend line and feasible region accurately without tedious calculation.
    Print ISSN: 0930-7516
    Electronic ISSN: 1521-4125
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
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  • 51
    Publication Date: 2018-03-14
    Description: Electro discharge machining (EDM) is an important manufacturing process for hard-to-cut-materials like nickel based alloys, e.g. alloy 718. Its high yield strength at high temperature makes it suitable as material for manufacturing of pressure vessels for high pressure / high temperature applications, in particular for ammonothermal pressure vessels. This report first summarizes the relationship between microstructure and properties of alloy 718 for practitioners. Second, it focuses on the metallographic description of alloy 718 surfaces proceeded by EDM and its behavior during use as equipment for ammonoacidic systems. Furthermore, this article includes the finding of suitable post processing, namely honing, to achieve high stability of the surface at high pressure atmosphere.
    Print ISSN: 0930-7516
    Electronic ISSN: 1521-4125
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
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  • 52
    Publication Date: 2018-03-14
    Description: Global change is affecting primary productivity in forests worldwide, and this, in turn, will alter long-term carbon (C) sequestration in wooded ecosystems. On one hand, increased primary productivity, for example, in response to elevated atmospheric carbon dioxide (CO 2 ), can result in greater inputs of organic matter to the soil, which could increase C sequestration belowground. On other hand, many of the interactions between plants and microorganisms that determine soil C dynamics are poorly characterized, and additional inputs of plant material, such as leaf litter, can result in the mineralization of soil organic matter, and the release of soil C as CO 2 during so-called “priming effects”. Until now, very few studies made direct comparison of changes in soil C dynamics in response to altered plant inputs in different wooded ecosystems. We addressed this with a cross-continental study with litter removal and addition treatments in a temperate woodland (Wytham Woods) and lowland tropical forest (Gigante forest) to compare the consequences of increased litterfall on soil respiration in two distinct wooded ecosystems. Mean soil respiration was almost twice as high at Gigante (5.0 μmol CO 2  m −2  s −1 ) than at Wytham (2.7 μmol CO 2  m −2  s −1 ) but surprisingly, litter manipulation treatments had a greater and more immediate effect on soil respiration at Wytham. We measured a 30% increase in soil respiration in response to litter addition treatments at Wytham, compared to a 10% increase at Gigante. Importantly, despite higher soil respiration rates at Gigante, priming effects were stronger and more consistent at Wytham. Our results suggest that in situ priming effects in wooded ecosystems track seasonality in litterfall and soil respiration but the amount of soil C released by priming is not proportional to rates of soil respiration. Instead, priming effects may be promoted by larger inputs of organic matter combined with slower turnover rates. Taken together, results of our cross-continental study with litter removal and addition treatments in a temperate woodland (Wytham Woods) and lowland tropical forest (Gigante forest) for comparing consequences of increased litterfall on soil respiration in two distinct wooded ecosystems showed that mean soil respiration was almost twice as high at Gigante than at Wytham but surprisingly, litter manipulation treatments had a greater and more immediate effect on soil respiration at Wytham. Importantly, despite higher soil respiration rates at Gigante, priming effects were stronger and more consistent at Wytham. Our results suggest that in situ priming effects in wooded ecosystems track seasonality in litterfall and soil respiration but the amount of soil C released by priming is not proportional to rates of soil respiration.
    Electronic ISSN: 2045-7758
    Topics: Biology
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  • 53
    Publication Date: 2018-03-14
    Description: Management, environment, and agroecosystem type are key factors influencing photosynthetic carbon (C) uptake and C use efficiency (CUE), calculated as the ratio of net ecosystem production to gross ecosystem production (NEP:GEP). Current literature has mainly emphasized annual C balance in studies involving multiple years with continuous monitoring of ecosystem C fluxes, yet CUE has not been thoroughly analyzed during the growing season, particularly in paired comparisons of contrasting types of pasture under semiarid conditions. From 2009 through 2013, we used eddy covariance method to determine daily, seasonal, and annual C budgets in rainfed alfalfa ( Medicago sativa L.) and grass ecosystems subjected to periodic harvest (haying) near Mandan, North Dakota, USA. We found consistently higher magnitudes of C fluxes (ecosystem respiration [ER], NEP, GEP) and hay production in alfalfa than grassland. Leaf area and canopy nitrogen content per unit land area were key driving factors for daily, seasonal, and annual differences in C fluxes between agroecosystems. Net ecosystem C balance indicated C losses occurred through haying in both ecosystems, though no changes in soil C stocks were detected in either ecosystem over the course of the study. Mean NEP:GEP ratios (±standard error) during periods of steady carbon dioxide (CO 2 ) uptake before and after haying were 0.43 ± 0.01 and 0.26 ± 0.03 for alfalfa and grassland, respectively, implying more efficient C use in the former. Moreover, alfalfa had consistently greater CUE than grassland despite variations in sunlight, temperature, and precipitation within and between growing seasons. Ratios of ER to GEP were also repeatedly lower in alfalfa than grassland in all five growing seasons. Under drought conditions, we infer alfalfa roots accessed water in the soil profile unavailable to more shallow-rooted grass species. Overall, hayed alfalfa was more efficient and tolerant than grassland in assimilating and using atmospheric CO 2 under variable intra- and inter-seasonal conditions. Outcomes from this study suggest the inclusion of alfalfa in unirrigated crop rotations can sustain high CUE, C uptake, and hay production while mitigating C losses in a semiarid environment.
    Electronic ISSN: 2150-8925
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 54
    Publication Date: 2018-03-14
    Description: An improved model to predict ·OH yield in hydrodynamic cavitation for wastewater treatment is developed. Relaxing the chemical equilibrium assumption, the model can estimate the global average ·OH yield during the whole oscillation cycle of all bubbles by considering radicals diffusion, cavitation event rate and bubble radius distribution. Reliability of the model is verified by comparing with experimental data in literature in terms of geometric and operating parameters. The results show that the maximum ·OH yield 1.2743×10 -4 mol·m -3 ·s -1 is achieved at optimal upstream pressure 3.6×10 5 Pa, while increasing downstream pressure always enhances ·OH yield. Decreasing the hole and pipe diameters benefits ·OH yield. Finally, a relevant correlation is developed for the design of cavitation reactors.
    Print ISSN: 0930-7516
    Electronic ISSN: 1521-4125
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
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  • 55
    Publication Date: 2018-03-14
    Description: Magnetic γ-Fe 2 O 3 catalysts were prepared by the microwave-assisted co-precipitation method utilizing direct-titrate and back-titrate precipitation technique with different precipitants ((NH 4 ) 2 CO 3 , NaOH, Na 2 CO 3 , and NH 4 OH), which were investigated in the selective catalytic reduction of NO x with NH 3 . The best γ-Fe 2 O 3 catalyst prepared method was direct-titration, using NH 4 OH as the precipitant, which exhibits a high de-NO x efficiency of above 90% at 325~400 °C. The direct-titration using NH 4 OH as the precipitant is effective to maintain the proper crystallization degree of γ-Fe 2 O 3 , improve the pore structure, and suppress the formation of α-Fe 2 O 3 phase, which are of benefits to get tiny and uniform discrete γ-Fe 2 O 3 particles with high activity in SCR. Meanwhile, NH 4 + -based precipitants in direct-titration leads to an increase of surface O/Fe atom ratio and more lattice oxygen sites are exposed to the crystal surface.
    Print ISSN: 0930-7516
    Electronic ISSN: 1521-4125
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
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  • 56
    Publication Date: 2018-03-14
    Description: Species composition is constrained by two upper-level processes in ecological contexts where the dispersion of organisms is not severely limited, namely selection and ecological drift. This intuitive framework has motivated a constant flow of empirical models for linking the species matrix to the local environmental descriptors, in which the environment rarely explains more than 30–40% of the variation in species composition. In most cases, researchers only approximate the environmental axes that drive fitness differences between species, as the list of measured descriptors reflect both logistical constraints and hypothesis-driven questions. Moreover, contextual factors, such as the species pool size (SPS) and the spatial extent of the sampled area, could moderate species–environment associations through sampling effects and dispersal limitations. This study's objective was to quantify the influence of contextual factors (i.e., related to the circumstances in which the study was conducted) on the species–environment association strength on the basis of a synthesis of 156 models of forest bird communities. Our results reveal that factors related to the SPS and the number of independent environmental axes studied affect our capacity to detect selection, whereas spatial factors such as the study's spatial extent and latitude are less important determinants. The study context explains almost a third of the observed variation in the strength of the species–environment association. We conclude that strong species–environment associations can be found for properly designed studies of forest bird communities, which raises the question of whether ecologists have underestimated the importance of selection in community assembly processes.
    Electronic ISSN: 2150-8925
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 57
    Publication Date: 2018-03-14
    Description: Termite mounds perform important roles in savanna ecosystems, generating heterogeneity and influencing ecosystem processes across multiple trophic levels. However, the influence the environment and neighboring termite colonies have on mound spatial patterning and structure is poorly understood, despite the profound implications such dynamics can have on ecosystems. To better understand these drivers, we mapped the spatial distribution and size of active and inactive Macrotermes mounds in eight 1-km 2 plots on contrasting geologies, nutrient-rich granite and nutrient-poor basalt, in a semi-arid Zimbabwean savanna. Although mound density was not significantly different between basalt (5.5 mounds/ha) and granite (6.1 mounds/ha), termite mound structural attributes and spatial distribution patterns varied greatly between geologies. Mound size distributions differed between the geologies and mounds were 2.6 times taller and 3.9 times wider and had 15 times greater lateral surface area on granite. Subsequently, 6% of the total landscape was covered by mounds on granite compared with only 0.4% on basalt. On granite, large mounds exhibited significant over-dispersion at scales below 30 m, signifying density-dependent thinning. Furthermore, small mounds were clustered around large mounds, likely a result of the budding of new colonies comprising fully fledged castes less vulnerable to competition. In contrast, random patterning was evident on comparably homogenous basalt. Our results demonstrate the powerful influence geological substrate has on mound spatial patterning and structure, suggesting that the importance of termite mounds for ecosystem functioning is more pronounced on nutrient-poor granitic substrates than basalts because of the pronounced over-dispersion, which maximizes mound production per unit area, and much larger mound sizes here.
    Electronic ISSN: 2150-8925
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 58
    Publication Date: 2018-03-14
    Description: Woody encroachment can lead to a complete switch from open habitats to dense thickets, and has the potential to greatly alter the biodiversity and ecological functioning of grassy ecosystems across the globe. Plant litter decomposition is a critical ecosystem process fundamental to nutrient cycling and global carbon dynamics, yet little is known about how woody encroachment might alter this process. We compared grass decay rates of heavily encroached areas with adjacent non-encroached open areas in a semi-arid South African savanna using litterbags that allowed or excluded invertebrates. We also assessed the effect of woody encroachment on termite activity, dominant decomposer organisms in savanna systems. We found a significant reduction in decomposition rates within encroached areas, with litter taking twice as long to decay compared with open savanna areas. Moreover, invertebrates were more influential on grass decomposition in open areas and termite activity was substantially lower in encroached areas, particularly during the dry season when activity levels were reduced to almost zero. Our results suggest that woody encroachment created an unfavourable environment for invertebrates, and termites in particular, leading to decreased decomposition rates in these areas. We provide the first quantification of woody encroachment altering the functioning of African savanna ecosystems through the slowing of aboveground plant decomposition. Woody encroachment is intensifying across the globe, and our results suggest that substantial changes to the carbon balance and biodiversity of grassy biomes could occur. This article is protected by copyright. All rights reserved.
    Print ISSN: 1354-1013
    Electronic ISSN: 1365-2486
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
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  • 59
    Publication Date: 2018-03-14
    Description: Stone covers on loessial slopes can increase the time of infiltration by slowing the velocity of the overland flow, which reduces the transport of solutes, but few mechanistic models have been tested under water-scouring conditions. We carried out field experiments to test a previously proposed, physically based model of water and solute transport. The area of soil infiltration was calculated from the uncovered surface area, and Richards' equation and the kinematic wave equation were used to describe water infiltration and flow along slopes with stone covers. The transport of chemicals into the runoff from the surface soil, presumably by diffusion, and their movement in the soil profile could be described by the convection-diffusion equations of the model. The simulated and measured data correlated well. The stones on the soil surface reduced the area available for infiltration but increased the Manning coefficient, eventually leading to increased water infiltration and decreased solute loss with runoff. Our results indicated that the traditional model of water movement and solute migration could be used to simulate water transport and solute migration for stone-covered soil on loessial slopes.
    Print ISSN: 0885-6087
    Electronic ISSN: 1099-1085
    Topics: Architecture, Civil Engineering, Surveying , Geography
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  • 60
    Publication Date: 2018-03-14
    Description: Climate change is rapidly reshaping arctic landscapes through shifts in vegetation cover and productivity, soil resource mobilization, and hydrological regimes. The implications of these changes for stream ecosystems and food webs is unclear and will depend largely on microbial biofilm responses to concurrent shifts in temperature, light, and resource supply from land. To study those responses, we used nutrient diffusing substrates to manipulate resource supply to biofilm communities along regional gradients in stream temperature, riparian shading, and dissolved organic carbon (DOC) loading in arctic Sweden. We found strong nitrogen (N) limitation across this gradient for gross primary production, community respiration and chlorophyll- a accumulation. For unamended biofilms, activity and biomass accrual were not driven by any single physical or chemical driver across this region. However, the magnitude of biofilm response to N addition did: in tundra streams, biofilm response was constrained by thermal regimes, whereas variation in light availability regulated this response in birch and coniferous forest streams. Furthermore, heterotrophic responses to experimental N addition increased across the region with greater stream water concentrations of DOC relative to inorganic N. Thus, future shifts in resource supply to these ecosystems are likely to interact with other concurrent environmental changes to regulate stream productivity. Indeed, our results suggest that in the absence of increased nutrient inputs, arctic streams will be less sensitive to future changes in other habitat variables such as temperature and DOC loading. This article is protected by copyright. All rights reserved.
    Print ISSN: 1354-1013
    Electronic ISSN: 1365-2486
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
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  • 61
    Publication Date: 2018-03-14
    Description: The redistribution of species has emerged as one of the most pervasive impacts of anthropogenic climate warming, and presents many societal challenges. Understanding how temperature regulates species distributions is particularly important for mobile marine fauna such as sharks given their seemingly rapid responses to warming, and the socio-political implications of human encounters with some dangerous species. The predictability of species distributions can potentially be improved by accounting for temperature's influence on performance, an elusive relationship for most large animals. We combined multi-decadal catch data and bio-logging to show that coastal abundance and swimming performance of tiger sharks Galeocerdo cuvier are both highest at ~22°C, suggesting thermal constraints on performance may regulate this species' distribution. Tiger sharks are responsible for a large proportion of shark bites on humans, and a focus of controversial control measures in several countries. The combination of distribution and performance data moves towards a mechanistic understanding of tiger shark's thermal niche, and delivers a simple yet powerful indicator for predicting the location and timing of their occurrences throughout coastlines. For example, tiger sharks are mostly caught at Australia's popular New South Wales beaches (i.e. near Sydney) in the warmest months, but our data suggest similar abundances will occur in winter and summer if annual sea surface temperatures increase by a further 1–2°C. Being able to predict how temperature regulates species distributions is particularly important for mobile marine animals such as sharks given their seemingly rapid responses to warming, and implications of human encounters with some dangerous species. We combined catch data and accelerometry tagging to show that coastal abundance and swimming activity of tiger sharks Galeocerdo cuvier are both highest at ~22°C. Our combination of distribution and performance data takes a step towards a mechanistic understanding of tiger shark's thermal niche, and delivers a simple indicator that may be useful for predicting coastal occurrences of this potentially dangerous species.
    Print ISSN: 1354-1013
    Electronic ISSN: 1365-2486
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
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  • 62
    Publication Date: 2018-03-14
    Description: Densely branched lateral roots (DBLRs) in Sesbania cannabina are formed in response to patchily distributed phosphorus (P) in volcanic soils. Little attention has been paid to morphological and physiological responses of DBLRs. Here, we investigated the relation between plant growth and DBLR development, enzymatic activities involved in P acquisition, and the influence of arbuscular mycorrhizal fungi (AMF), which contribute to P uptake, to clarify the function of DBLRs. We investigated DBLR development induced by localized application of P fertilizer and we compared the activities of phosphoenolpyruvate carboxylase (PEPCase) and acid phosphatase (APase) between DBLRs and non-DBLRs. Additionally, plants were grown with or without AMF to investigate the effect of AMF colonization on the numbers of DBLRs and plant P uptake, and we compared AMF colonization between DBLRs and non-DBLR roots. Secondary to quaternary lateral DBLRs were produced after the primary lateral roots passed near P fertilizer. P i content per DBLR increased as DBLRs developed, promoting higher shoot growth. Under P deficiency, PEPCase and APase activities increased in non-DBLR, but were significantly lower in DBLRs in the same plants. AMF inoculation changed the root system architecture by significantly decreasing the number of DBLRs, and AMF colonization was lower in DBLRs than in non-DBLRs. Our results indicate that DBLR formation is a P-coacquisition strategy of S . cannabina grown in P-deficient andosolic soil. Roots that form DBLR are clearly different from non-DBLR roots in morphological and biochemical response and AMF symbiosis.
    Print ISSN: 1436-8730
    Electronic ISSN: 1522-2624
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 63
    Publication Date: 2018-03-14
    Description: Product/service-systems (PSS) that focus on selling service and performance instead of products are often mentioned as means to realize a circular economy (CE), in which economic growth is decoupled from resource consumption. However, a PSS is no implicit guarantee for a CE, and CE strategies do not necessarily lead to decoupling economic growth from resource consumption in absolute terms. Absolute resource decoupling only occurs when the resource use declines, irrespective of the growth rate of the economic driver. In this forum paper, we propose a two-step framework that aims to support analyses of PSS and their potential to lead to absolute resource decoupling. In the first step, we present four PSS enablers of relative resource reduction that qualify as CE strategies. In the second step, three subsequent requirements need to be met, in order to successfully achieve absolute resource decoupling. Conditions and limitations for this accomplishment are discussed. Danish textile cases are used to exemplify the framework elements and its application. We expect that the framework will challenge the debate on the necessary conditions for CE strategies to ensure absolute resource decoupling.
    Print ISSN: 1088-1980
    Electronic ISSN: 1530-9290
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 64
    Publication Date: 2018-03-14
    Description: The mobility of landslides on Mars is studied based on a database of 3,118 events. To establish the volume of the landslides for the whole dataset based on the deposit area, a new volume-area relationship based on a representative dataset of 222 landslides is used. Plotting the H/L ratio between fall height H and runout L versus volume, landslide mobility is analyzed and compared with existing empirical relationships for Martian and terrestrial landslides. Analyzing the mobility in terms of normalized residuals, i.e., the relative deviation of the H/L ratio from the dataset best-fit line, mobility is found to depend on both the landslide location on Mars, and landslide typology. This allows us to identify four different types of high mobility (hypermobile) landslides. Three classes of high mobility landslides are associated respectively to meteoroid impact, the Olympus Mons aureoles, and landslides with Toreva-block failure style, and their mobility can be explained by the peculiar flow mechanics. The fourth class includes landslides associated with isolated craters, those in the regions wetted by the putative Oceanus Borealis, and the ones at high latitudes. We suggest that the common factor behind all the hypermobile landslides of this fourth kind is the presence of ice. This is confirmed by our data showing that landslides increase in mobility with latitude. The latitudinal trend mirrors the distribution of ice as detected by radar, neutron probes, and the presence of glacial and layered ejecta morphologies. Because the overall landslide distribution supports the presence of ice-lubricated conditions, two ice lubrication models are presented showing how ice melting within or underneath the landslides could enhance mobility. By proper analysis in terms of apparent friction residuals, we find that the mobility of landslides in Valles Marineris with the largest landslide concentration is lower than average. We explain this circumstance partly from the smaller role of ice in equatorial Valles Marineris, and partly because the collapses from high slope relief imply high-speed impact with the floor valley confinement, loss of momentum, and decrease in mobility. Environmental consequences imply that the present subsurface ice distribution may have been persistent throughout the Amazonian period.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
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  • 65
    Publication Date: 2018-03-14
    Description: The existence of uncertainties and variations in data represents a remaining challenge for life cycle assessment (LCA). Moreover, a full analysis may be complex, time-consuming, and implemented mainly when a product design is already defined. Structured under-specification, a method developed to streamline LCA, is here proposed to support the residential building design process, by quantifying environmental impact when specific information on the system under analysis cannot be available. By means of structured classifications of materials and building assemblies, it is possible to use surrogate data during the life cycle inventory phase and thus to obtain environmental impact and associated uncertainty. The bill of materials of a building assembly can be specified using minimal detail during the design process. The low-fidelity characterization of a building assembly and the uncertainty associated with these low levels of fidelity are systematically quantified through structured under-specification using a structured classification of materials. The analyst is able to use this classification to quantify uncertainty in results at each level of specificity. Concerning building assemblies, an average decrease of uncertainty of 25% is observed at each additional level of specificity within the data structure. This approach was used to compare different exterior wall options during the early design process. Almost 50% of the comparisons can be statistically differentiated at even the lowest level of specificity. This data structure is the foundation of a streamlined approach that can be applied not only when a complete bill of materials is available, but also when fewer details are known.
    Print ISSN: 1088-1980
    Electronic ISSN: 1530-9290
    Topics: Energy, Environment Protection, Nuclear Power Engineering
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  • 66
    Publication Date: 2018-03-14
    Description: High zinc (Zn) concentration of seeds has beneficial effects both on seed vigor and human nutrition. This study investigated the effect of Zn biofortification on growth of young durum wheat ( Triticum durum cv. Yelken) seedlings under varied Zn and water supply. The seeds differing in Zn concentrations were obtained by spraying ZnSO 4 to durum wheat plants at different rates under field conditions. Three groups of seeds were obtained with the following Zn concentrations: 9, 20, and 50 mg Zn kg −1 . The seeds differing in Zn were tested for germination rate, seedling height, shoot dry matter production, and shoot Zn concentration under limited and well irrigated conditions in a Zn-deficient soil with and without Zn application. In an additional experiment carried out in solution culture, root and shoot growth and superoxide dismutase activity (SOD) of seedlings were studied under low and adequate Zn supply. Low seed Zn concentration resulted in significant decreases in seedling height both in Zn-deficient and sufficient soil, but more clearly under water-limited soil condition. Decrease in seed germination due to low seed Zn was also more evident under limited water supply. Increasing seed Zn concentration significantly restored impairments in seedling development. Drought-induced decrease in seedling growth at a given seed Zn concentration was much higher when soil was Zn-deficient. Increasing seed Zn concentration also significantly improved SOD activity in seedlings grown under low Zn supply, but not under adequate Zn supply. The results suggest that using Zn-biofortified seeds assures better seed vigor and seedling growth, particularly when Zn and water are limited in the growth medium. The role of a higher antioxidative potential ( i.e ., higher SOD activity) is discussed as a possible major factor in better germination and development of seedlings resulting from Zn-biofortified seeds.
    Print ISSN: 1436-8730
    Electronic ISSN: 1522-2624
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 67
    Publication Date: 2018-03-14
    Description: Balanced applications of nitrogen (N), phosphorus (P), and potassium (K) are known to increase grain yield of wheat but the impact of the interactions among N, P, and K on root growth and nitrogen use efficiency (NUE) have not been proven. The aim of this study was to investigate the effect of balanced applications of N, P, and K on the rooting patterns and NUE of wheat. Two glasshouse experiments were conducted. A rhizobox study was used to assess the impact of interactions among N, P, and K fertilisers on total root length, biomass, specific root length, root length density, N use efficiency (NUE), and N uptake efficiency of the shoots (NUpE shoot ) and N nutrition index. In a separate pot study, plants were grown to maturity to confirm the effect of the observed changes in root growth on NUE, NUpE grain , and grain/biomass yield. In the rhizobox experiment when plants were supplied with N+P+K, total root biomass increased approximately six-fold relative to plants grown with N alone or with no fertiliser. Plants exposed to N+P+K had NUpE shoot and NUE values that were five and ten times higher, respectively, than plants that received just fertiliser N. Plants supplied with N+P or N+P+K had N nutrition indices close to one (N-adequate), while plants that only received N had an index of 0.62 (N-deficient). The pot study confirmed that the changes in root length and biomass in plants exposed to N+P+K resulted in significant increases in NUE, NUpE grain , shoot biomass, and grain yield at maturity. Interactions among fertiliser N, P, and K played a critical role in influencing root biomass and length, which was associated with increases in NUE, NUpE shoot and NUpE grain .
    Print ISSN: 1436-8730
    Electronic ISSN: 1522-2624
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 68
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    Wiley-Blackwell
    Publication Date: 2018-03-14
    Print ISSN: 0739-4462
    Electronic ISSN: 1520-6327
    Topics: Biology
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  • 69
    Publication Date: 2018-03-14
    Description: The inability of organisms to cope in changing environments poses a major threat to their survival. Rising carbon dioxide concentrations, recently exceeding 400 μatm, are rapidly warming and acidifying our oceans. Current understanding of organism responses to this environmental phenomenon is based mainly on relatively short- to medium-term laboratory and field experiments, which cannot evaluate the potential for long-term acclimation and adaptation, the processes identified as most important to confer resistance. Here, we present data from a novel approach that assesses responses over a centennial timescale showing remarkable resilience to change in a species predicted to be vulnerable. Utilising museum collections allows the assessment of how organisms have coped with past environmental change. It also provides a historical reference for future climate change responses. We evaluated a unique specimen collection of a single species of brachiopod ( Calloria inconspicua ) collected every decade from 1900 to 2014 from one sampling site. The majority of brachiopod shell characteristics remained unchanged over the past century. One response, however, appears to reinforce their shell by constructing narrower punctae (shell perforations) and laying down more shell. This study indicates one of the most calcium-carbonate-dependent species globally to be highly resilient to environmental change over the last 120 years and provides a new insight for how similar species might react and possibly adapt to future change. Current knowledge of how organisms will respond to ocean warming and acidification is based on relatively short- to medium-term laboratory and field experiments, which cannot evaluate the potential for adaptation. We present a novel approach of utilising museum collections of a brachiopod species collected every decade at one site from 1900 to 2014 to assess how organisms have coped with past environmental change. This study indicates the resilience of one of the most vulnerable species globally to environmental change over the past 120 years and provides an insight for how similar species might react to future change.
    Print ISSN: 1354-1013
    Electronic ISSN: 1365-2486
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
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  • 70
    Publication Date: 2018-03-14
    Description: The weakening in the relationship between the South China Sea summer monsoon onset (SCSSMO) and the low-level cross-equatorial flow (CEF) in May is investigated using the ERA-Interim reanalysis data sets during 1979–2016. The SCSSMO–SCSCEF relationship has experienced a significant inter-decadal change, and the correlation coefficient becomes weaker after the late 1990s. The correlation has shifted from the significant negative value in the earlier decade to insignificant in the later decade. This inter-decadal change is robust under several sensitive tests and largely independent of the El Niño-Southern Oscillation signal. One possible explanation is the change in mechanisms driving the SCSSMO over the course of the two periods. Before the late 1990s, the northwards march of the intertropical convergence zone, which has a close relationship with the SCSCEF, is mainly responsible for the SCSSMO. After the late 1990s, warming of the western North Pacific favours more tropical cyclones and disturbances during May. The westwards movement of these tropical disturbances would affect the SCSSMO and help explain why the SCSSMO–SCSCEF relationship became weaker in the later decade. (a) The time series of SCSSMO (bar) and SCSCEF (curves) in May of different levels (including 850 hPa, 925 hPa, and 10 m; data from ERAInterim), (b) the 11-year sliding correlation (partial correlation) between the SCSSMO and SCSCEF (after removing ENSO signal in May or preceding winter); the dashed line denotes the 90% confidence level; (c) same as (b), but for the 925 hPa SCSCEF calculated by NCEP/NCAR, NCEP-DOE, and averaged from May 1 to June 8 (which contains 90% of the SCSSMO) by ERA-Interim; (d) the composited 925 hPa SCSCEF with respect to SCSSMO during 1979–1998 and 1999–2016 (date 0 is defined as the onset, while the signs of “−” and “+” denote the dates before and after the onset). Thin and thick lines denote the daily and 5-day mean of composited SCSCEF, respectively.
    Print ISSN: 0899-8418
    Electronic ISSN: 1097-0088
    Topics: Geosciences , Physics
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  • 71
    Publication Date: 2018-03-14
    Description: The February–May rainfall season, locally known as Belg, contributes up to 40% of the annual rainfall over northeastern, central and southwestern Ethiopia. Its contribution exceeds 50% over southern and southeastern Ethiopia. The Belg season is characterized by significant inter-annual and intra-seasonal variability. However, there are only a few studies addressing the characteristics of this season. Interactions between extratropical and tropical systems across the Red Sea region play a major role in modulating the rainfall pattern during this season. It is shown in this article that the North Atlantic Oscillation (NAO) seems to play a major role in the variability of the Belg rains on the sub-seasonal time scale. The Belg rains are negatively correlated with the NAO index over much of the region, with southern and southeastern Ethiopia exhibiting relatively highest correlation values. NAO rainfall anomaly composites also indicate that the negative (positive) phase of the NAO tends to enhance (suppress) the Belg rains. Two modes of regional circulation patterns that modulate Belg rainfall variability have also been identified in this study. A ridge/trough pattern, featuring two anomalous mid- to upper-level warm anticyclones and one cold cyclonic trough in the region between the northeast Atlantic and the Arabian Peninsula, tends to suppress the Belg rainfall due to reduced tropical–extratropical interactions. In contrast, a tripole structure with two anomalous mid- to upper-level cold cyclonic troughs and one warm anticyclone tends to enhance rainfall during the Belg season of Ethiopia. It is further shown in this article that the Madden–Julian Oscillation (MJO) tends to modulate rainfall during the Belg season. Composites of circulation anomalies at 500 hPa (above) shows a tripole circulation pattern in the form of anticyclone–cyclone–anticyclone (ACA) for dry Belg (a)–(d) and cyclone–anticyclone–cyclone (CAC) for wet Belg (e)–(h). The ACA and CAC patterns indicate influence of tropical/extratropical interactions in modulating the Ethiopian Belg rainfall. NAO-related anomalies in the North Atlantic are also linked to anomalies in the Red Sea region through the tripole pattern.
    Print ISSN: 0899-8418
    Electronic ISSN: 1097-0088
    Topics: Geosciences , Physics
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  • 72
    Publication Date: 2018-03-14
    Description: Aridity is a permanent feature of climate based on long-term climatic conditions over a region. Climatic indices are reliable tools to explore climate type, and climatologists have proposed various indices to classify climate and investigate the aridity or humidity in any region. In this study, we examined spatiotemporal variations of aridity in Iran during the last six decades from 1954 to 2013, using the de Martonne aridity index ( I DM ), which is calculated based on precipitation and temperature. Data used in this study were extracted from the Global Precipitation Climatology Centre and the University of Delaware gridded data sets, respectively. Both data sets have global high-resolution (0.5° × 0.5°) coverage, and temporally span more than a century of data (from 1901). According to the data obtained from these data sets, more than 80% of Iran has an arid and semi-arid climate (annually), although the spatial pattern of I DM varies throughout the year. Using the Mann–Kendall test showed a negative significant trend in I DM in 20% of Iran's total area in spring, and less than 7% in the other seasons of the year. Overall, it can be concluded that there were no significant trends in aridity for most parts of Iran during the last six decades. Results of this study showed a spatiotemporal non-significant negative or positive trend in aridity, in most of the months and seasons of the year and also annually, in Iran, using the de Martonne aridity index ( I DM ) and the Mann–Kendall (MK) trend test, based on Global Precipitation Climatology Centre and the University of Delaware gridded data sets.Spatial pattern of MK Z-values for the annual I DM time series during 60 years period from 1954 to 2013.
    Print ISSN: 0899-8418
    Electronic ISSN: 1097-0088
    Topics: Geosciences , Physics
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  • 73
    Publication Date: 2018-03-14
    Description: Understanding how different climate factors interact and impact rice yield is essential for effective agricultural management strategies and policies. However, the potential impacts are less clear at the regional scale. In this work, we used the latest version of the ORYZA crop model to evaluate the impacts of climate change and carbon dioxide (CO 2 ) on rice yields in the Sichuan Basin of China based on high-quality agricultural experimental, meteorological and soil data and the incorporation of future climate data generated by five general circulation models (GCMs) under three newly released representative concentration pathway (RCP) 2.6, 4.5 and 8.5 scenarios. Considering climate change alone, our modelling results indicated a continuing rice reduction for most stations by 2–17, 4–28 and 1–43% under the RCP2.6, 4.5 and 8.5 scenarios, respectively; when considering the CO 2 fertilizer effect, rice yields increased by 3–10, 4–13 and 5–20% under the RCP2.6, 4.5 and 8.5 scenarios, respectively. However, for most stations, the CO 2 fertilizer effect could not completely offset the negative impacts of climate change on rice yields. In addition, temperature and radiation were the main climate factors that cause yield variation by affecting the rice maturity periods (DAE), spikelet fertility factor (SPFERT) and spikelet number (NSP). The uncertainty arising from the climate models was less than 10% under the RCP2.6 scenario, 15% under the RCP4.5 scenario and 20% under the RCP8.5 scenario, indicating good consistency in rice yield simulations. These findings offer insight into the physiological mechanisms and the degree of climate change impacts on rice yields, thus informing appropriate adaptive strategies for rice planting in the Sichuan Basin, China. We use the ORYZA v3 model, coupled with climate data generated by five general circulation models (GCMs) under three representative concentration pathways (RCPs) (2.6, 4.5 and 8.5), to simulate climate change impacts on rice yields in the Sichuan Basin of China. We collect high-quality meteorological, soil and agricultural experimental data at the plot scale to calibrate, validate and evaluate the crop model. We identify the main factors that affect rice yields, explore the degree and the physiological mechanisms of climate change on rice yields and quantify the uncertainty arising from climate models.
    Print ISSN: 0899-8418
    Electronic ISSN: 1097-0088
    Topics: Geosciences , Physics
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  • 74
    Publication Date: 2018-03-14
    Description: Lapse rate (LR) of near-surface (2 m) air temperature is essential for determining spatially distributed and gridded air temperature interpolated from in situ observational sites. However, due to the limitation of sparse observational networks, high-resolution LRs are not usually available on regional scales, especially in mountainous regions. The purpose of this study is to estimate LRs for the entire Tibetan Plateau (TP) using observed air temperature and moderate-resolution imaging spectroradiometer (MODIS) night-time land surface temperatures (LSTs) and to analyse the spatio-temporal changes of the estimated LRs. First, diurnal cycles of LRs derived from in situ observations in three subregions of the TP were analysed, which shows that the LRs in the western and northeastern regions were shallow in the cold season and steep in the warm season, whereas the southeastern region exhibited a different pattern. Further comparisons revealed that the LRs for night-time air temperatures better represented the LRs for daily mean air temperatures than the daytime ones, and the night-time MODIS LSTs correlated well with the night-time air temperatures, especially for the MODIS Terra data sets. Therefore, the night-time MODIS LSTs from the Terra data sets were used to estimate high-resolution (10 km) LRs for the daily mean temperatures over the entire TP. Estimated LRs over most areas of the TP were shallower than the commonly used environmental LR (−6.5 K/km). The LRs in the southeastern region were steeper than those in the northeastern region, while steeper LR values occurred in the northwestern region with lower temperatures and less humidity. Study region with subregions and spatial distribution and elevation of the 85 stations (denoted by blank circles). The colour represents the DEM (m) from the shuttle radar topography mission (SRTM). The range of station elevations (solid bar with diagonal) as well as the number of stations in each region (solid bar). Further division of regions 2 and 3 into regions A–D occurred to validate estimated daily mean temperature and LR.
    Print ISSN: 0899-8418
    Electronic ISSN: 1097-0088
    Topics: Geosciences , Physics
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