ALBERT

Description: We examined the relationships between large wood (LW) export and precipitation patterns and intensity by analyzing the data on the annual volume of LW removed from 42 reservoirs and the daily precipitation at or near the reservoir sites. We also calculated the effective precipitation by considering the antecedent precipitation. Both daily and effective precipitation data were used as explanatory variables to explain LW export. The model selection revealed that the precipitation pattern and intensity controlling LW export varied with latitude in the Japanese archipelago. In small watersheds with narrow channel widths and low discharges, mass movements, such as landslides and debris flows, are major factors in the production and transport of LW. In this case, the effective precipitation required to initiate mass movements regulated the LW export and did not vary with the latitude. In intermediate and large watersheds with wide channel widths and high stream discharges, heavy rainfall and subsequent floods regulated buoyant depth, influencing the initiation of LW movement. In southern and central Japan, intense rainfall accompanied by typhoons or localized torrential downpours causes geomorphic disturbances, which introduce abundant pieces of LW into the channels. However, these pieces continue to be removed by repeated rainfall events. Therefore, LW export is supply-limited and potentially produces less LW accumulation. Conversely, in northern Japan, where typhoons and torrential downpours are rare, LW export is transport-limited because LW pieces recruited by bank erosion, tree mortality, and windthrow accumulate and persist on valley floors. These pieces may be easily exported by infrequent flooding.

Description: We developed a method to measure in situ the isotopic composition of liquid water with minimal supervision and, most important, with a temporal resolution of less than a minute. For this purpose a microporous hydrophobic membrane contactor (Membrana) was combined with an isotope laser spectrometer (Picarro). The contactor, originally designed for degassing liquids, was used with N2 as a carrier gas in order to transform a small fraction of liquid water to water vapor. The generated water vapor was then analyzed continuously by the Picarro analyzer. To prove the membrane's applicability, we determined the specific isotope fractionation factor for the phase change through the contactor's membrane across an extended temperature range (8°C–21°C) and with different waters of known isotopic compositions. This fractionation factor is needed to subsequently derive the liquid water isotope ratio from the measured water vapor isotope ratios. The system was tested with a soil column experiment, where the isotope values derived with the new method corresponded well (R2 = 0.998 for δ18O and R2 = 0.997 for δ2H) with those of liquid water samples taken simultaneously and analyzed with a conventional method (cavity ring-down spectroscopy). The new method supersedes taking liquid samples and employs only relatively cheap and readily available components. This makes it a relatively inexpensive, fast, user-friendly, and easily reproducible method. It can be applied in both the field and laboratory wherever a water vapor isotope analyzer can be run and whenever real-time isotope data of liquid water are required at high temporal resolution.

Description: Transit time of discharge is a hydrological characteristic used in water resource management. Previous studies have demonstrated large spatial variation in the mean transit time (MTT) of stream base flow in meso-scale catchments. Various relationships between topography and MTT have been reported. Although it is generally assumed that base flow MTT is controlled by the depth of the hydrologically active layer that recharges a stream, this hypothesis has not been tested in field studies. This study confirmed that the depth of hydrologically active soil and bedrock controls spatial variation in MTT. The study used isotopic and geochemical tracer data gathered in the 4.27 km2 Fudoji catchment, central Japan. The results, together with previously documented relationships between topography and MTT, indicate that the depth of the hydrologically active layer is sometimes, but not always, related to topography. A comprehensive understanding of the factors that control base flow production in mountainous catchments will require further study of the water flow path depths that recharge streams.

Description: Two drugs that were thought not to be of benefit in the later stages of Alzheimer's disease have been shown to hold back severe decline by four months

Description: Hopes dashed of personalised drug treatments after two-thirds of genetic mutations in the same tumour are found to vary from one biopsy to the next

Description: This paper examines the long-term historical changes in frequency and amplitude of hydroclimatic extremes in the Blue Nile basin using data from the second half of 20th century. The temporal variability of basin-wide rainfall extremes and river flow extremes from four gauging stations was investigated under the hypothesis of no trend and no persistence in time. On the basis of a quantile anomaly analysis method, decadal variations in extreme daily, monthly, and annual quantiles were studied, and the periods of statistical significance were identified. The analysis showed that high and low river flows and rainfall depths do not vary in time in a fully random way but show a particular variation pattern. Their extremes show significant decadal variations. The 1980s had statistically significant negative anomalies in extremes in comparison with the long-term reference period of 1964–2009, while the 1960s–1970s and the 1990s–2000s had positive anomalies, although less significant. There is neither consistent increasing nor decreasing trend in rainfall and flow extremes of recent years. Therefore, anticipated trends due to global warming could not be identified. Conversely, low-flow extremes show an increasing trend during the last decade, which could be related to the effect of water regulation works at the outlet of Lake Tana. Moreover, similar patterns and statistically significant correlations were found between climatic indices representing the Pacific and Atlantic Oceans and the Blue Nile rainfall and flow extremes. Changes that occur on the Pacific Ocean appear to be a main driver for the decadal oscillations in climate and related high and low Blue Nile water availability for Ethiopia, Sudan, and Egypt.

Description: Few studies exist on infiltration processes in badlands, although infiltration and subsurface lateral flows are known to contribute to soil erosion and to control slope instability. Our investigation was carried out in a 100 m² plot located in a 0.5 ha landslide in black marls (South-East France). An artificial sprinkling was performed with an intensity of 10 mm.h -1 during 66.4 h interrupted with 8.4 h. breaks. KBr and KCl were used as tracers. A pseudo-steady state was reached after 25-35 hours and 250-350 mm of rainfall. The runoff coefficient was 40% (ratio total runoff volume/total sprinkling water amount). Pre-event water (PE) contributed to the groundwater recharge at the very beginning of the experiment but PE contribution dropped steadily while the soil was saturating. After around 200 mm cumulative rainfall, PE contribution started to rise steeply before reaching a nearly constant value. This original mechanism implies an efficient transfer process of PE. It was assumed from the description of the material structure and from hydrological evidences that PE was mainly drained from a structure porosity made of the marl's flaked nature. Total pre-event water contributions ranged from 25 to 79 % (PE contribution was over 50 % in 2/3 of the observations wells). Over the recession phase, release of pre-event water occurred from the drainage of a texture porosity. The study showed that at the plot scale, infiltration processes proved well organised despite the high heterogeneity and anisotropy of the material. It was possible to propose a general conceptual model explaining the hydrological processes over time and area. The peculiar structure of regolith originating from black marl is preserved over a large part of the weathering time, so that the material structure (type, orientation of grains, small/large pores) remains a first order control of water flow generation in Black marl soils. Copyright © 2012 John Wiley & Sons, Ltd.

Description: In this work, the multifractal properties of hourly rainfall data recorded at a location in Southern Spain have been related to the scale properties of the corresponding Intensity-Duration-Frequency (IDF) curves. Four parametric models for the IDF curves have been fitted to the quantiles of rainfall obtained by using the Generalized Pareto frequency distribution function with the extreme data series obtained for the same place. The scaling of the rainfall intensity moments has been analysed and the empirical moments scaling exponent function has been obtained. The corresponding values of q 1 and γ 1 have been empirical and theoretically calculated and compared to some characteristics of the different IDF models. Thus, the scaling behaviour of IDF curves has been analysed and the best model has been selected. Copyright © 2012 John Wiley & Sons, Ltd.

Description: A reliable procedure for measuring parameters connected to surface roughness is needed to compare the gas sensing properties of various thin films or the effect of different fabrication procedures on the surface roughness and the sensing properties. In this article, we propose to investigate how the acquisition parameters specific to atomic force microscopy investigations such as pixel size, scan area and scan speed influence the roughness parameters, namely root mean square and surface area ratio, commonly used for characterizing the gas sensing properties of porphyrins and other materials. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: The magnitude 9 megaquake that shook the east coast of Japan in March 2011 reactivated dormant faults close to Fukushima's beleaguered nuclear reactors

Description: Major-ion compositions of groundwater are employed in this study of the water-rock interactions and hydrogeochemical evolution within a carbonate aquifer system. The groundwater samples were collected from boreholes or underground tunnels in the Ordovician limestone of Yanzhou Coalfield where catastrophic groundwater inflows can be hazardous to mining and impact use of the groundwater as a water supply. The concentration of TDS ranged from 961 to 3,555 mg/l and indicates moderately to highly mineralized water. The main water-type of the middle Ordovician limestone groundwater is Ca-Mg-SO 4 , with SO 4 2- ranging from 537 mg/l to 2,297 mg/l, and average values of Ca 2+ and Mg 2+ of 455.7 mg/l and 116.6 mg/l, respectively. The water samples were supersaturated with respect to calcite and dolomite and undersaturated or saturated with respect to gypsum. Along the general flow direction, deduced from increases of TDS and Cl - , the main water-rock interactions that caused hydrogeochemical evolution of the groundwater within the aquifer were the dissolution of gypsum, the precipitation of calcite, the dissolution or precipitation of dolomite, and ion exchange. Ion exchange is the major cause for the lower mole concentration of Ca 2+ than that of SO 4 2- . The groundwater level of Ordovician aquifer is much higher than that of C-P coal-bearing aquifers, so the potential flow direction is upward and the pyrite in coal is not a possible source of sulfate, additional data on the stable sulfur and oxygen isotopic composition of the sulfate may be helpful to identify its origin. Although ion exchange probably accounts for the higher mole concentration of Na + than that of Cl - , the dissolution of aluminosilicate can not be ruled out. The data evaluation methods and results of this study could be useful in other areas to understand flow paths in aquifers and to provide information needed to identify the origin of groundwater. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Quantitative evaluation of the effect of climate variability and human activities on runoff is of great importance for water resources planning and management in term of maintaining the ecosystem integrity and sustaining the society development. In this paper, hydro-climatic data from 4 catchments (i.e., Luanhe River Catchment, Chaohe River Catchment, Hutuo River Catchment and Zhanghe River Catchment) in the Haihe River Basin from 1957–2000 were used to quantitatively attribute the hydrological response (i.e., runoff) to climate change and human activities separately. To separate the attributes, the temporal trends of annual precipitation, potential evapotranspiration (PET) and runoff during 1957–2000 were first explored by the Man-Kendall test. Despite that only Hutuo River Catchment was dominated by significant negative trend in annual precipitation, all four catchments presented significant negative trend in annual runoff varying from −0.859 mm a -1 (Chaohe River) to −1.996 mm a -1 (Zhanghe River). Change points in 1977 and 1979 are detected by precipitation-runoff double cumulative curves method and Pettitt's test for Zhanghe River and other three rivers, respectively, and are adopted to divide data set into two study periods as the pre-change period and post-change period. Three methods including hydrological model method, hydrological sensitivity analysis method and climate elasticity method were calibrated with the hydro-climatic data during the pre-change period. And then, hydrological runoff response to climate variability and human activities were quantitatively evaluated with the help of the three methods and based on the assumption that climate and human activities are the only drivers for streamflow and are independent to each other. Similar estimates of anthropogenic and climatic effects on runoff for catchments considered can be obtained from the three methods. We found that human activities were the main driving factors for the decline in annual runoff in Luanhe River Catchment, Chaohe River Catchment and Zhanghe River Catchment, accounting for over 50% of runoff reduction. However, Climate variability should be responsible for the decrease in annual runoff in the Hutuo River Catchment. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Measurements of river water quality at Haridwar, India, taken during 2005 – 2006 show that the river water does not meet the WHO and Bureau of Indian Standards criteria of drinking water quality, especially with respect to total coliform and fecal-coliform. This study investigates the removal of pathogens at a river bank filtration (RBF) site in Haridwar. Using the quality of river water and the quality of abstracted water from a nearby production well, semi-empirical models based on the concept of filtration coefficient are developed and tested for their effectiveness in removing pathogens under varying bacteriological quality of source water. A two-tier model which includes the effect of clogged layer is developed to obtain an equivalent filtration coefficient. This coefficient is found to be linearly related with natural logarithm of the concentration of pathogens in the source water. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Nonpoint source pollution and hydromodification are the leading causes of impairment to our nation's rivers and streams. Roadside ditch networks, ubiquitous in both rural and urban landscapes, intercept and shunt substantial quantities of overland runoff and shallow groundwater to stream systems. By altering natural flowpaths, road ditches contribute not only to hydromodification but also potentially to nonpoint-source (NPS) pollution by acting as hydrologic links between agricultural fields and natural streams. Unfortunately, the impacts of these alterations on watershed hydrology and water quality are not well understood. Through a series of field measurements, including field surveys and discharge monitoring, this study examined the effect of road ditch networks on basin morphometry, field- and watershed-scale hydrology, and pollutant transport in a 38 km 2 agricultural watershed in south-central NY. Salient findings include: (i) 94% of road ditches discharged directly to natural streams, effectively doubling the drainage density, (ii) on average, road ditches increased peak and total event flows in their receiving streams by 78% and 57%, respectively, but displayed significant variation across ditches, (iii) ditches intercepted large quantities of surface and subsurface runoff from agricultural fields and therefore represent efficient conduits for the transport of agricultural NPS pollutants to sensitive receiving waterbodies. Our results provide useful information for hydrologists who wish to further understand how artificial drainage may be affecting watershed hydrology and for managers and engineers tasked with designing appropriate flood and NPS pollution control measures. Copyright © 2012 John Wiley & Sons, Ltd.

Description: We coupled the process-based NIES Integrated Catchment-based Eco-hydrology (NICE) model to an urban canopy model (UCM) and the Regional Atmospheric Modeling System (RAMS) in order to simulate the effect of urban geometry and anthropogenic exhaustion on the hydrothermal changes in the atmospheric/land and the interfacial areas of the Japanese megalopolis. The simulation was conducted with multi-scale in horizontally regional–urban–point levels, and in vertically atmosphere–surface–unsaturated–saturated layers. The model reproduced reasonably the observed hydrothermal values by using ground-truth data in various types of natural/artificial land covers. The simulated results also suggested that the latent heat flux in new water-holding pavement (consisting of porous asphalt and water-holding filler made of steel by-products based on silica compound) has a strong impact on hydrologic cycle and cooling temperature in comparison with the observed heat budget by newly incorporating the effect of water amount on the heat conductivity in the pavement. Furthermore, the model predicted the hydrothermal changes under two types of land cover scenarios to promote evaporation and to reduce air temperature against heat island phenomenon. Finally, we evaluated the relationship between the effect of groundwater use to ameliorate the heat island and the effect of infiltration on the water cycle in the catchment. These procedures to integrate the multi-scaled model simulation with political scenario based on the effective management of water resources as heat sink/source would be very powerful approaches to recovering a sound hydrologic cycle and create thermally-pleasing environments in the megalopolis. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Soil and vadose zone profiles are used as an archive of changes in groundwater recharge and water quality following changes in land use in an area of the Loess Plateau of China. A typical rain-fed loess-terrace agriculture region in Hequan, Guyuan is taken as an example and multiple tracers (chloride mass balance, stable isotopes, tritium, and water chemistry) are used to examine groundwater recharge mechanisms and to evaluate soil water chloride as an archive for recharge rate and water quality. Results show that groundwater recharge beneath natural uncultivated grassland, used as a baseline, is about 94–100 mm yr -1 and the time it takes for annual precipitation to reach water table through the thick unsaturated zone is from decades to hundreds of years (tritium free). This recharge rate is 2–3 orders of magnitude more than in the other semiarid areas with similar annual rainfall and with deep rooted vegetation and relatively high temperature. Most of the water that eventually becomes recharge originally infiltrated in the summer months. The conversion from native grassland to winter wheat has reduced groundwater recharge by 42–50% (50–55 mm yr -1 for recharge), and from winter wheat to alfalfa resulted in a significant chloride accumulation in the upper soil zone which terminated deep drainage. The paper also evaluates the time lag between potential recharge and actual recharge to aquifer and between increase in solute concentration in soil moisture and that in the aquifer following land-use change due to the deep unsaturated zone. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Shallow upland drains, grips, have been hypothesized as responsible for increased downstream flow magnitudes. Observations provide counterfactual evidence, often relating to the difficulty of inferring conclusions from statistical correlation and paired catchment comparisons; and the complexity of designing field experiments to test grip impacts at the catchment-scale. Drainage should provide drier antecedent moisture conditions, providing more storage at the start of an event; but, grips have higher flow velocities than overland flow so potentially delivering flow more rapidly to the drainage network. We develop and apply a model for assessing the impacts of grips upon flow hydrographs. The model was calibrated on the gripped case; then the gripped case was compared with the intact case by removing all grips. This comparison showed that even given parameter uncertainty, the intact case had significantly higher flood peaks and lower baseflows, mirroring field observations of the hydrological response of intact peat. The simulations suggest that this is because delivery effects may not to translate into catchment-scale impacts for three reasons. First, in our case, the proportions of flow path lengths that were hillslope were not changed significantly by gripping. Second, the structure of the grip network as compared with the structure of the drainage basin mitigated against grip-related increases in the concentration of runoff in the drainage network, although it did marginally reduce the mean timing of that concentration at the catchment outlet. Third, the effect of the latter upon downstream flow magnitudes can only be assessed by reference to the peak timing of other tributary basins, emphasizing that drain effects are both relative and scale dependent. However, given the importance of hillslope flow paths, we show that if upland drainage causes significant changes in surface roughness on hillslopes, then critical and important feedbacks may impact upon the speed of hydrological response. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Natural soil pipes are found in peatlands but little is known about their hydrological role. This paper presents the most complete set of pipe discharge data to date from a deep blanket peatland in northern England. In a 17.4-ha catchment, we identified 24 perennially-flowing and 60 ephemerally-flowing pipe outlets. Eight pipe outlets along with the catchment outlet were continuously gauged over an 18-month period. The pipes in the catchment were estimated to produce around 13.7 % of annual streamflow with individual pipes often producing large peak flows (maximum peak of 3.8 L s -1 ). Almost all pipes, whether ephemeral, perennially-flowing, shallow or deep (outlets 〉 1 m below the peat surface), showed increased discharge within a mean of 3 hours after rainfall commencement and were dominated by stormflow, indicating good connectivity between the peatland surface and the pipes. However, almost all pipes had a longer time period between hydrograph peak and return to baseflow compared to the stream (mean of 23.9 hours for pipes, 19.7 hours for stream). As a result, the proportion of streamflow produced by the pipes at any given time increased at low flows and formed the most important component of stream discharge for the lowest 10 % of flows. Thus, a small number of perennially-flowing pipes became more important to the stream system under low flow conditions and probably received water via matrix flow during periods between storms. Given the importance of pipes to streamflow in blanket peatlands, further research is required into their wider role in influencing stream-water chemistry, water temperature and fluvial carbon fluxes, as well as their role in altering local hydrochemical cycling within the peat mass itself. Enhanced piping within peatlands caused by environmental change may lead to changes in streamflow regime with larger low flows and more prolonged drainage of the peat. Copyright © 2012 John Wiley & Sons, Ltd.

Description: The hydrology of Quebec (Canada) boreal fens is poorly documented. Many peatlands are located in watersheds with impounded rivers. In such cases, their presence influences reservoir inflows. In recent years, some fens have been subjected to an increase of their wet area, a sign that they may be evolving towards an aquatic ecosystem. This dynamic process is referred to as aqualysis. This paper presents the seasonal and monthly hydrological budgets of a small watershed including a highly aqualysed fen (James Bay region). Monitoring of precipitation ( P ), runoff ( Q ) and groundwater levels ( WL ) was conducted during the ice-free season. Three semi-empirical equations (Thornthwaite, Priestley-Taylor and Penman-Monteith) were used and compared to calculate potential evapotranspiration ( PET ). The first two equations, having fewer parameters, estimate higher PET values than the third equation. The use of pressure level gauges installed in wells, for the calculation of peatland water storage, is inconclusive. Swelling of peat, peat decomposition and plant composition could be responsible for non-negligible amounts of absorbed water, which are not entirely accounted for by well levels. The estimation of peat matrix water storage is potentially the largest source of error and the limiting factor to calculate water balances in this environment. The results show that the groundwater level and the water storage vary depending on the season and especially after a heavy rainfall. Finally, the results illustrate the complexity of water routing through the site and, thus, raise several questions to be resolved in the future. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Drugs that clamp onto a pathogen's vital enzymes when they are at their most reactive can combat a range of infections

Description: Virus particles and viral inclusions were detected by transmission electron microscopy examination of sections of the seminal vesicles and mucus gland of asymptomatic young drones from colonies of Apis mellifera lightly infested by Varroa mite. In the mucus gland the infection was found in the muscular sheath and epithelium, while in the seminal vesicle in cells of the outer serosa. Isolated viral particles were also observed in the hemolymph occupying the intercellular spaces of the muscular sheath fibers. In the muscle the virus appeared as polygonal crystalloid inclusions, while in the epithelium mainly inside cytoplasmic vesicles. The infected cells apparently are not damaged. The virus particles are present in the hemolymph and forming more mature structures, as crystalloids, in the muscle. This suggests that the virus is liberated in the body fluid and infects the tissues penetrating the cells through endocytosis. The presence of virus in mucus gland epithelial vesicles raise the possibility of its transference to the gland secretion and therefore, to the semen. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.

Description: Belgium, the Netherlands and Luxembourg all punch above their weight when it comes to scientific innovation - and career opportunities

Description: Creating a haven for science is no simple feat in the Philippines, a country where evolution and fossils are controversial topics

Description: As early humans expanded beyond hunter-gatherer groups, religion was the glue that held societies full of strangers together, says Ara Norenzayan

Description: Those who would dance on religion's grave are underestimating its staying power, says Robert N. McCauley

Description: Further to your Instant Expert on sleep (4 February), I found a way to maximise the efficiency of sleep cycles when in Antarctica during the...

Description: • The story about a fire at a Brazilian Antarctic base (3 March, p 5) should have said most bases use non-flammable building materials...

Description: Can't live with him, can't live without him. In a special series of articles we lay out a new vision that resets the terms of the debate

Description: What is dark matter? Or gravity? Why is the universe so smooth? There's a particle for every conundrum, say Valerie Jamieson and Richard Webb

Description: Your article on dingo conservation and the Azaria Chamberlain inquest (18 February, p 28) reminded me of a pup I bought for my daughter from...

Description: Ben Haller's letter (25 February, p 36) about your editorial on brain-eavesdropping (4 February, p 3) makes a reasonable point regarding the possible...

Description: Your item on Jurassic katydid calls suggests that sounds at 6. 4 kilohertz "can travel long distances" (11 February, p 18). In fact, there is...

Description: Animals thinking inside a virtual world can help us understand what can go wrong in the brain

Description: Clusters of cells instrumental in building complex brains have been found in a simple worm that barely has a brain at all

Description: The prehistoric sea-level rise long thought to have been caused by the ice sheet melting may actually have been down to local subsidence

Description: The aim of this study was to evaluate the persistence of resin cement residues after dentin surface cleaning with different alcohol-based solutions or an essential oil (eucalyptol). Forty bovine teeth were sectioned in order to expose pulp chamber dentin to be washed with 1.0 mL of 2.5% sodium hypochlorite (NaOCl), followed by 0.1 mL of 17% EDTA application for 3 min, and final irrigation with 2.5% NaOCl. The specimens were air dried and resin-based cement was rubbed onto the dentine surface with a microbrush applicator. After 15 min, the surface was scrubbed with a cotton pellet and moistened with different dentin cleaning solutions, compounding the following groups: G1—95% ethanol, G2—70% ethanol, G3—70% isopropyl alcohol, or G4—eucalyptol. The dentin was scrubbed until the cement residues could not be visually detected. Sections were then processed for SEM and evaluated at ×500 magnification. Scores were attributed to each image according to the area covered by residual sealer, and data were subjected to Kruskal–Wallis at 5% significance. Eucalyptol promoted the most adequate dentin cleaning, although no statistical difference was detected amongst the groups ( P 〉 0.05), except between the eucalyptol and 70% ethanol groups ( P 〈 0.05). All the evaluated dentin cleaning solutions were unable to completely remove the cement residues from the dentin surface. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.

Description: In The Emotional Life of Your Brain , Richard J. Davidson has devised simple surveys based on solid neuroscience to help you shape your own grey matter

Description: Religions are not literally true but neither are they total nonsense. Atheists need to reclaim the useful bits, Alain de Botton tells Graham Lawton

Description: In his new novel, The Sensorium of God , Stuart Clark catalogues the messy international and interpersonal politics at the time of Newton's breakthroughs

Description: Religions are not literally true but neither are they total nonsense. Alain de Botton explains why atheists need to reclaim the useful bits

Description: Our minds solve fundamental problems in a way that leaves a god-shaped space just waiting to be filled by religion, explains Justin L. Barrett

Description: Human interactions influence how technology turns out, and not always for the better, argues Henry Petroski in To Forgive Design

Description: Your report on electric racing cars mentions charging mats built into the track to allow inductive charging on the go, and suggests the mats be...

Description: In your lost scientific treasures article, you mentioned Damascus steel (4 February, p 40). This material was made from high-carbon "wootz" steel made in...

Description: The unusual four-winged dinosaur was coated with dark iridescent feathers – not all of them used for flight, it seems

Description: Circumcised men reduced their risk of prostate cancer by 15 per cent, but only if they had the operation before having sex for the first time

Description: Free apps spend most of their power sending targeted adverts – and can drain your cellphone battery in 90 minutes

Description: Facebook has the power of a nation state, but is not living up to its moral responsibilities, says former CNN bureau chief Rebecca MacKinnon

Description: This close-up of a pride of feasting lions was taken by armoured photographic robot as it trundled across the Masai Mara

Description: This study evaluated the effects on human enamel after two bleaching procedures: with a fluoridated bleaching agent and with topical fluoride application postbleaching. It used 43 enamel blocks (3 mm 2 ) that were ground flat (600–2,000 grit) and polished with polishing paste (one and one-fourth). Specimens were randomly divided into three groups according to the bleaching procedure: (1) control group, (2) hydrogen peroxide 35% (HPF) and topical application of fluoride 1.23%, and (3) HP 38% (OP) with fluoride in its composition. Bleaching agents were used according to the manufacturer's instructions. Three methodologies were used: nanoindentation, to observe surface hardness and elastic modulus; atomic force microscopy, to observe surface roughness ( R a − R z ); and scanning electron microscopy, to observe the enamel surface effects. Group OP had a decrease in the elastic modulus after bleaching, which was recovered at 14 days. An increased roughness ( R a ; 32%) was observed on group HPF and had an increased erosion on enamel surface (67%). It was concluded that topical application of fluoride, after using the nonfluoridated whitening agent, increased the roughness values and erosion of enamel. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: Feature/edge-preserving noise removal techniques have a strong potential in several application domains including medical image processing. Magnetic resonance (MR) images have a tendency to gain Rician noise during acquisition. In this article, we have presented genetic algorithms based adapted selective non-local means (GASNLM) filter-based scheme for noise suppression of MR images while preserving the image features as much as possible. We have applied GASNLM filter with optimal parameter values for different frequency image regions to remove the noise. Filter parameter values are optimized by genetic algorithm (GA). A change in NLM filter known as selective weight matrix is also proposed to preserve the image features. The results prove soundness of the method. We have compared results with many well known and latest techniques, and the improvements are discussed. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: Whether an ultimate creator as envisaged by religion exists or not is a question that science can address, argues Victor J. Stenger

Description: OBJECTIVES: The aim of this in vitro study was to investigate the efficacy of in-office bleaching technique combined with the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI Paste–MI) at different moments and its influence on enamel surface properties. METHODS: Eighty bovine dental crowns were randomly allocated into eight groups ( n = 10), and bleached with either 35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four different protocols of application of MI were considered: without MI, MI applied before bleaching, MI applied after bleaching, and MI applied both before and after bleaching. Bleaching effectiveness was measured by the VITA EasyShade spectrophotometer utilizing the CIEL*a*b* system (Δ E , Δ L *, Δ a *, and Δ b *). Color readings were measured at baseline, 7, 14, and 21 days. Hardness and roughness were measured at baseline (T0) and immediately after bleaching (T14). Data were subjected to the two-way ANOVA for repeated measurements and Tukey's test at 5%. RESULTS: HP groups achieved the greatest color change. The application of a CPP-ACP paste did not reduce the efficacy of bleaching peroxides. Samples bleached with CP showed decreased hardness at T14. Samples bleached with HP that received the application of MI before and before/after bleaching did not present hardness decrease at T14. Samples bleached with peroxides only and received MI after bleaching showed increased roughness at T14. CONCLUSIONS: The use of CPP-ACP was able to prevent negative changes in roughness and hardness of bovine enamel when associated to hydrogen peroxide, and might be applied before/after the bleaching protocol. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.

Description: Ticks are ectoparasites of great medical and veterinary importance around the world and synthetic chemicals such as permethrin have been used for their control. This study provides a cytochemistry analysis of both degenerative and cell death processes in salivary glands of the brown dog tick Rhipicephalus sanguineus semi-engorged females exposed to 206, 1,031, and 2,062 ppm of permethrin. The results presented herein demonstrate that permethrin is a potent chemical acaricide that would act on the glandular tissue's morphophysiology in this tick species by eliciting severe changes in the acinus shape, intense vacuolation of the acinar cells' cytoplasm, marked glandular tissue disorganization, culminating in an advanced degenerative stage with consequent formation of many apoptotic bodies (cell death). In addition, permethrin induced major changes in the acinar cells' nucleus, such as a change both in its shape and size, chromatin marginalization, nuclear fragmentation, and appearance of picnotic nuclei, especially when the highest concentrations of the product were used. Thus, permethrin induced early degeneration of this tissue characterized by significant changes in the structure of acinar cells and production of enzymes related to the cell death process, in addition to interfering directly in the genetic material of these cells. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.

Description: After receiving injections of human embryonic stem cells, monkeys with tremors and rigidity were able to move smoothly

Description: Some snails survive inside bird guts for hours at a time, and travel hundreds of kilometres that way before popping out at the other end

Description: Rapid switch between neutrino flavours could herald experiments to explore early universe's preference for matter

Description: Why can everyone learn Portuguese? Is Twitter a trivialiser? A whistle-stop tour of our intellectual landscape in the company of Noam Chomsky

Description: The pumping organ of blood-sucking female mosquitoes has a three-dimensional (3D) structure. However, conventional two-dimensional imaging methods are insufficient for visualizing the 3D structure in detail. Furthermore, their 3D imaging tasks are highly time consuming and sample preparation process requires elaborate skill. Among 3D imaging techniques, synchrotron X-ray microscopic computed tomography (SR-μCT) is especially suitable for small insects with opaque cuticles, such as mosquitoes. In this study, the 3D morphological structure of the pump system of a female mosquito was visualized using SR-μCT. Expandable volume capacities of two pump chambers were measured for several mosquito samples of similar size. To verify the cross-sectional images acquired by SR-μCT, complementary paraffin-sectioning data were compared. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.

Description: Frictional interactions between wires and brackets reduce the efficacy in orthodontic treatments. Self-ligating brackets (SLBs) are now more often used due to lower frictional forces when compared with conventional-ligating brackets. In this study, scanning electron microscopy and atomic force microscopy were used to examine the microstructural effects of stainless steel and ceramic SLBs on the surface roughness of stainless steel and superelastic NiTi wires both after in vivo clinical orthodontic treatment as well as in in vitro three-point bending experiments. A combination of two wires—0.019 in. × 0.025 in. stainless steel wires and 0.016 in. superelastic NiTi wires—and two SLBs—both passive-type stainless steel SLBs and active-type ceramic SLBs—was applied for 4 months (bicuspid-extraction) in an in vivo setting and for 1 month in an in vitro setting (200 g loads). After the SLB treatments, all wires exhibited severe scratches secondary to frictional interactions with the brackets. When used with the stainless steel SLBs (Damon 3MX®), the surfaces of 0.019 in. × 0.025 in. stainless steel ( P 〈 0.0001) and 0.016 in. superelastic NiTi wires ( P 〈 0.05) were significantly smoother than when used with the ceramic SLBs (Clippy-C®). Such results suggest that orthodontic treatments with stainless steel SLBs are more effective than with ceramic SLBs. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: To determine whether sodium hypochlorite (NaOCl) with 0.2% chlorhexidine gluconate (CHX) leads to colour change and precipitate formation, and to ultrastructurally analyse the dentine surface after simultaneous irrigation with 0.5% NaOCl and 0.2% CHX. Four tubes in which 5ml of different NaOCl concentrations and 5ml 0,2% CHX were placed, were observed every 15 minutes in the first two hours and after 7 days. Mixture solutions were centrifuged at 800 rpm/4 min. A precipitate is observed under light-microscopy. Thirty-five single-rooted teeth were instrumented using crown-down technique with irrigation: Positive control: distilled water, Negative control: 0,5% NaOCl+15% EDTA, Experimental group: identical to the negative control, then canals were treated with 0.5% NaOCl+0.2% CHX. The longitudinal root sections were observed under scanning-electron-microscopy. The amount of debris was assessed with 5/score-system, and the results were analysed using the Mann-Whitney U test (p 〈 0.001). Change in colour was noticed immediately after the merger and it did not change with time. Mixture solutions showed considerable turbidity, but precipitate was observed only after centrifugation. Statistical analysis showed a significant difference in the dentinal wall purity when comparing the cervical and middle root canal thirds between the experimental and negative control group. The difference was also observed between the cervical and middle thirds compared to the apical third of the root canal within these groups. Interaction between NaOCl and CHX, as well as the creation of precipitates, depends not only on the concentration of NaOCl, but also on the concentration of CHX. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: Religions are not literally true but neither are they total nonsense. Alain de Botton explains why atheists need to reclaim the useful bits

Description: Political "microtargeting" via social media is a double-edged sword

Description: Leafcutter ants of the genus Atta Fabricius are serious agricultural pests. Morphological studies of immature stages within this group are few, and the data provided for species of considerable importance are usually incomplete. In this study, the immatures of Atta sexdens Linnaeus are described and compared using light and scanning electron microscopy. Only specimens from founding stage colonies (i.e., lacking adult workers) were used. The existence of four larval instars was estimated by a frequency plot of maximum head widths, and the larvae of different instars differed from each other mainly by their bodily dimensions. Worker larvae belonged to two distinct morphological castes: (1) gardeners and nurses and (2) within-nest generalists. The worker larvae described in this study differed from a previous description of the same species by the following traits: the existence of a genal lobe, the number of clypeal hairs, the presence of two hairs on the ninth abdominal somite, the presence of hairs on the anterior surface of the labrum, and the shape of the maxillary palpus. This study provides a comparative analysis of immature stages of A. sexdens that may be relevant to future morphological and biological studies of the Attini. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.

Description: MRI and PET scans have revealed how the genetic condition affects brain development, and might one day help to predict symptoms of Williams syndrome

Description: The model of atoms as mini solar systems was supplanted by quantum fuzziness – now atoms have been forced to act more like the classical systems

Description: Attempts to fly drones in civilian airspace are a classic example of an irresistible force (innovation) meeting an immovable object (the law)

Description: Mind-reading technology notwithstanding, there is no prospect of anyone looking inside your skull without your consent

Description: Potential climate change effects on aspects of conjunctive management of water resources can be evaluated by linking climate models with fully integrated groundwater–surface water models. The objective of this study is to develop a modeling system that links global climate models with regional hydrologic models, using the California Central Valley as a case study. The new method is a supply and demand modeling framework that can be used to simulate and analyze potential climate change and conjunctive use. Supply-constrained and demand-driven linkages in the water system in the Central Valley are represented with the linked climate models, precipitation-runoff models, agricultural and native vegetation water use, and hydrologic flow models to demonstrate the feasibility of this method. Simulated precipitation and temperature were used from the GFDL-A2 climate change scenario through the 21st century to drive a regional water balance mountain hydrologic watershed model (MHWM) for the surrounding watersheds in combination with a regional integrated hydrologic model of the Central Valley (CVHM). Application of this method demonstrates the potential transition from predominantly surface water to groundwater supply for agriculture with secondary effects that may limit this transition of conjunctive use. The particular scenario considered includes intermittent climatic droughts in the first half of the 21st century followed by severe persistent droughts in the second half of the 21st century. These climatic droughts do not yield a valley-wide operational drought but do cause reduced surface water deliveries and increased groundwater abstractions that may cause additional land subsidence, reduced water for riparian habitat, or changes in flows at the Sacramento–San Joaquin River Delta. The method developed here can be used to explore conjunctive use adaptation options and hydrologic risk assessments in regional hydrologic systems throughout the world.

Description: A selection of the responses from the forensic scientists who took our survey

Description: Our survey of UK forensic scientists reveals that many are concerned that closure of the Forensic Science Service will lead to miscarriages of justice

Description: In The Joy of Sin , Simon Laham presents compelling evidence that indulging in your darker side need not necessarily be bad

Description: In Beautiful Souls , Eyal Press writes a beautiful narrative of whistle-blowers and refuseniks, but seeks in vain to pin down their psychological profile

Description: The "cuddle chemical" oxytocin bonds mothers to their babies and sniffing it makes adults nicer – but can also foster gloating and racism

Description: Nearly all our fresh water comes from obscure underground deposits – now satellites and radioactive isotopes are telling us how much we have to go round

Description: Imagine charging your cellphone from a meadow or harvesting electricity from rice paddies. The technology works, but can we make plant power a staple crop?

Description: I had no idea beetles could be such pests, as in the case of the bark beetle damaging North American forests (5 November 2011, p...

Description: In his letter, Brian Robinson says that, during a time of austerity, a hiatus in pursuit of the mysteries of the cosmos would not matter...

Description: • Saul (not Sam) Winstein was the champion of unconventional carbocation chemistry (21 January, p 34...

Description: Further to Michael Dowling's letter calling for the creation problem in cosmological theory to be left to philosophers rather than physicists like Stephen Hawking...

Description: Felicitas Arias of the International Bureau of Weights and Measures suggests we stop adding leap seconds to coordinated universal time (UTC), which is based on...

Description: Your feature on the idea of progress in evolution included palaeontologist Simon Conway Morris's suggestion that ice ages would have killed off the dinosaurs...

Description: Jesse Prinz offers that "philosophy tells us what is possible, and science tells us what is true" (21 January, p 26). This serves us well...

Description: Do British people know enough about the financial interests of those writing health articles? Time to toughen editorial codes, asks James Davies

Description: The unique pattern of your heartbeat could one day be used to encrypt hard drives and other electronics

Description: Australia has a long history of ecological disaster from alien species - so why is ecologist David Bowman proposing adding yet another?

Description: Books and formal papers make knowledge look finite, knowable. By embracing the unfinished, unfinishable forms of the web we are truer to the spirit of enquiry - and to the world we live in, says David Weinberger

Description: How the Lola-Drayson electric concept car gets its juice is even more impressive than its flat-out speed

Description: Parents and those newly head-over-heals show greater activation of brain areas related to parental attachment when they see a baby than single people

Description: A 15 kilometre-long swatche of seagrass off the coast of Spain is at least 80,000 years old, making it the oldest living organism that we know of on Earth

Description: An efficient approach is developed to analytically evaluate solute transport in a horizontal, divergent radial flow field with a multistep injection flow rate and an arbitrary input concentration history. By assuming a piecewise steady state flow and transforming the time domain to the cumulative injected flow domain, the concentration distribution is found to be completely determined by the total volume of injected flow and independent of specific flow rates. Thus, on the cumulative flow domain, the transport problem with a temporally varying velocity field can be transformed into a steady state flow problem. Linear convolution can then be applied on the cumulative injected flow domain to evaluate the solution for an arbitrarily time-dependent input concentration. Solutions on the regular time domain can be conveniently obtained by mapping the solution on the cumulative injected flow domain to the time domain. Furthermore, we theoretically examine the conditions for the assumption of piecewise steady state flow to be valid. On the basis of the critical time scale of the “pseudosteady state condition,” defined as when velocity changes accomplish 99% of their steady state differences, and the relative error in the mean travel time of plume front, we obtain conditions for neglecting the transitional period between two pumping steps. Such conditions include the following: (1) the duration of a pumping step, tp, must be longer than the critical time scale, tc, i.e., tp ≥ tc = 25r2S/T, where r is the radial distance, S is the storage coefficient, and T is the transmissivity, or similarly, a maximum problem domain needs to be defined for a given pumping strategy. (2) the maximum well pumping rate, qmax, should satisfy qmax ≤ πθT/25S, where θ is the effective porosity. When both conditions are satisfied, transitional periods may be neglected.

Description: Meander bends in alluvial rivers morphologically evolve toward meander cutoff with narrowing intra-meander necks, and this should steepen hydraulic gradients and intensify intra-meander hyporheic flux. This research used dye tracking and head loss measurements in a 1:500 planimetrically scaled laboratory river table to quantify the spatial and temporal intensification of intra-meander flux rates at two evolution ages. The younger meander bend, M1, had a sinuosity of 2.3, a river neck width of 0.39 cm, and 0.6% river slope, and the older meander bend, M3, had a sinuosity of 5.2, a river neck width of 0.12 cm, and 0.5% river slope. Flux into and out of the meander bend was estimated along the normalized curvilinear distance s *, with the meander neck at s * = 0.1 and s * = 0.9, the meander centroid at s * = 0.37 and s * = 0.63, and the apex at s * = 0.5. Between the meander centroid and neck we documented a 60% spatial intensification for M1 and a 90% spatial intensification for M3. Between M1 and M3 we documented a 135% temporal intensification at the neck and a 100% intensification at the centroid. Our empirical spatial and temporal intensification rates involving the M1 and the M3 scenario were 1 to 3 times lower than theoretical rates derived from a river evolution model with equivalent M1 and M3 planimetry. Over estimation by the theoretical model was attributed to exaggerated head loss caused by the model neglecting groundwater contributions to river stage. Hyporheic exchange provides critical ecosystem services and its spatial and temporal variation with meander evolution should be considered in river management. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Watershed models which combine hydrology and water quality are being widely utilized in integrated watershed management for the determination of best water management practices. In this study, the hydrology of the Lower Porsuk Stream Watershed in Turkey has been modeled with SWAT to determine optimal water management strategies. The calibration and validation process have been accomplished using data from two monitoring stations. The model has been run for the 1978–2009 period and while the 1998–2004 period has been used for calibration, the validation has spanned the whole period. The SWATCup calibration and uncertainity program has been utilized for this purpose. No significant differences have been detected among different iteration numbers in the calibration period. The monthly Nash-Sutcliffe and R 2 performance indicatiors for the upstream Esenkara station have been 0.74 and 0.88, respectively for the calibration period, and 0.87 and 0.87, respectively for the validation period. The Kıranharmanı station which is located close to the watershed outlet has shown values of 0.59 and 0.72, respectively for the calibration period, and 0.44 and 0.56, respectively for the validation period. There are uncertanities in the abstracted irrigation and groundwater quantities which have reflected in the results in the Kıranharmanı station which is more affected as it lies downstream of the irrigation areas. The effects of different irrigation practices on the flow regime have been also investigated. A scenario has been implemented in which drip irrigation wholly replaces conventional furrow and sprinkler irrigation. The scenario has shown increases in stream flows by 87 % for the whole year. The adoption of more efficient irrigation practices thus results in reducing the water stress induced by irrigation demands. With this study a modeling framework has been founded to aid water management applications in the Lower Porsuk Stream Watershed by generating scenarios for best management practices. Copyright © 2012 John Wiley & Sons, Ltd.