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Purpose: Over the last 60 years, intensification of soil cultivation led to an acceleration of soil erosion and sediment delivery to river systems. In Martinique, this acceleration has led to the remobilization of a toxic insecticide (i.e. chlordecone) used in the 1970s-1990s to control banana weevil. A previous study attributed this accelerated remobilization to the application of glyphosate in plantations from the 1990s onwards. To further unambiguously confirm this link, the identification of soil erosion sources supplied to coastal sediment is essential. Methods: Accordingly, sediment fingerprinting tools were adapted and applied to a coastal sediment core collected in the Galion Bay. Potential source samples (n=37) were collected across the drainage area. Along with the coastal sediment core layers, these samples were analysed for potential tracing properties. The optimal suite of tracers was then selected and introduced into an un-mixing model to quantify their contributions to coastal sediment. Results: Results showed that subsoil (i.e. soil layer < 30 cm depth) and banana plantation soil surface supply the major sources of sediment (49-78% and 12-36%, respectively) to the Galion Bay and that their contributions increased since 2000, in line with chlordecone and glyphosate fluxes. Conclusion: This evolution may be attributed to the higher sensitivity of banana plantations to erosion that may have been enhanced by the glyphosate application leaving the soil uncovered with vegetation and to the contamination of both topsoil and deep soil layers ( < 30 cm) layers with chlordecone due to its vertical transfer along the soil profile and its redistribution across hillslopes. [ABSTRACT FROM AUTHOR]

Background: Although confidence does not automatically imply competence, it does provide pharmacy students with a sense of empowerment to manage a pharmacotherapeutic problem independently. Among the methods used in higher education, there is growing interest in simulation. Aim: To evaluate the impact of simulation on pharmacy students' confidence in performing clinical pharmacy activities. Method: Articles that reported the use of simulation among pharmacy students with fully described outcomes about confidence were included. Studies for which it was impossible to extract data specific to pharmacy students or simulation were excluded. The search was carried out in Medline, Embase, Lissa and PsycInfo from inception to August the 31th, 2022. The results were synthesized into 4 parts: confidence in collecting information, being an expert in a procedure/pathology, counselling and communicating, and other results. The quality assessment of included studies was conducted using the Mixed Methods Appraisal Tool "MMAT" tool. Results: Among the 39 included articles, the majority were published in the last 5 years and conducted in the United States. The majority included pharmacy students in years 1 through 3 (69.2%). The most common study design was the pre-post uncontrolled design (66.7%). Studies measuring the effects of human and/or virtual simulation were mainly focused on confidence to counsel and/or communicate with patients and colleagues (n = 20). Evaluations of the effects of these types of simulation on confidence in information gathering by health professionals were also well represented (n = 16). Conclusion: Simulation-based training generally yielded positive impact on improving pharmacy students' confidence in performing clinical pharmacy activities. Rigorous assessment methods and validated confidence questionnaires should be developed for future studies. [ABSTRACT FROM AUTHOR]

The receptor-binding domain, region II, of the Plasmodium vivax Duffy binding protein (PvDBPII) binds the Duffy antigen on the reticulocyte surface to mediate invasion. A heterologous vaccine challenge trial recently showed that a delayed dosing regimen with recombinant PvDBPII SalI variant formulated with adjuvant Matrix-MTM reduced the in vivo parasite multiplication rate (PMR) in immunized volunteers challenged with the Thai P. vivax isolate PvW1. Here, we describe extensive analysis of the polyfunctional antibody responses elicited by PvDBPII immunization and identify immune correlates for PMR reduction. A classification algorithm identified antibody features that significantly contribute to PMR reduction. These included antibody titre, receptor-binding inhibitory titre, dissociation constant of the PvDBPII-antibody interaction, complement C1q and Fc gamma receptor binding and specific IgG subclasses. These data suggest that multiple immune mechanisms elicited by PvDBPII immunization are likely to be associated with protection and the immune correlates identified could guide the development of an effective vaccine for P. vivax malaria. Importantly, all the polyfunctional antibody features that correlated with protection cross-reacted with both PvDBPII SalI and PvW1 variants, suggesting that immunization with PvDBPII should protect against diverse P. vivax isolates. [ABSTRACT FROM AUTHOR]

The invasion of reticulocytes by Plasmodium vivax merozoites is dependent on the interaction of the Plasmodium vivax Duffy Binding Protein (PvDBP) with the Duffy antigen receptor for chemokines (DARC). The N-terminal cysteine-rich region II of PvDBP (PvDBPII), which binds DARC, is a leading P. vivax malaria vaccine candidate. Here, we have evaluated the immunogenicity of recombinant PvDBPII formulated with the adjuvants Matrix-M and GLA-SE in mice. Analysis of the antibody responses revealed comparable ELISA recognition titres as well as similar recognition of native PvDBP in P. vivax schizonts by immunofluorescence assay. Moreover, antibodies elicited by the two adjuvant formulations had similar functional properties such as avidity, isotype profile and inhibition of PvDBPII-DARC binding. Furthermore, the anti-PvDBPII antibodies were able to block the interaction of DARC with the homologous PvDBPII SalI allele as well as the heterologous PvDBPII PvW1 allele from a Thai clinical isolate that is used for controlled human malaria infections (CHMI). The cross-reactivity of these antibodies with PvW1 suggest that immunization with the PvDBPII SalI strain should neutralize reticulocyte invasion by the challenge P. vivax strain PvW1. [ABSTRACT FROM AUTHOR]

We study the leakage of fluids (liquids or gases) in syringes with glass barrel, steel plunger and rubber O-ring stopper. The leakrate depends on the interfacial surface roughness and on the viscoelastic properties of the rubber. Random surface roughness is produced by sandblasting the rubber O-rings. We present a very simple theory for gas flow which takes into account both the diffusive and ballistic flow. The theory shows that the interfacial fluid flow (leakage) channels are so narrow that the gas flow is mainly ballistic (the so called Knudsen limit). We compare the leakrate obtained using air and helium. For barrels filled with water we observe no leakage even if leakage occurs for gases. We interpret this as resulting from capillary (Laplace pressure or surface energy) effects. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to explore the beliefs, perceptions and representations of patients in order to identify the determinants of oral anticancer drugs adherence and to take action in current practice to improve patient support in digestive oncology.Methods: We constructed a semi-directed interview guide which aimed to explore the patient's relationship with medication, their health history, their experiences at the time of the announcement of treatment, their confidence, their fears, their motivations to adhere to their treatment and the constraints linked to their treatment. The data were analysed and discussed using a thematic approach.Results: Seventeen patients agreed to participate in the study. The median age was 60 years. Ten patients had colorectal cancer, 3 patients had hepatocellular carcinoma, 3 patients had gastrointestinal stromal tumour and 1 patient had neuroendocrine pancreatic tumour. We identified five categories of factors influencing adherence: demographic and socioeconomic, disease-related, treatment-related, care system-related, and patient representation and pathways' factors. A majority of patients emphasised the importance of family support in the adherence process and the convenience of per os treatment compared to other intravenous treatments. However, several negative determinants emerged such as the toxicity of the treatment, fears of forgetting to take the medication, difficulties with the galenic formulation and negative beliefs of the family.Conclusion: This study demonstrates the need to address the different dimensions of the patient in order to understand his or her behaviour with regard to adherence and to identify the levers for improvement. [ABSTRACT FROM AUTHOR]

As flood events are expected to become more frequent due to climate change, investigating how overland flow exports terrestrial nutrients, carbon and living organisms into aquatic systems is essential for understanding both soil and stream ecosystem status. Here we assessed how dissolved organic carbon (DOC), total suspended sediments (TSS), and stream bacterial diversity responded to stream discharge and overland flow during stormflow in a tropical catchment. A higher humification index and a decreasing ratio of allochthonous to autochthonous DOC indicated that DOC from soils was exported to stream during the flood. The δ13C and δ15N of particulate matter was indicative of a source in the cultivated areas of the upper catchment and of subsurface soils (stream banks and gullies) in the downstream section. Bacterial richness of particle-attached (PA) and the free-living (FL) fractions increased with the flood progression in the upstream section. Moreover, the community structure of the PA fraction in the stream was more similar to that of overland flow than was the FL fraction. This suggests that the soil PA bacterial community was washed-out with overland flow during the flood recession. The relative contribution of sources and the composition of TSS, rather than hydrological regime, significantly drove the composition of bacterial community. In conclusion, our results emphasize that overland flow during a flood event strongly influences the structure of stream bacterial communities further underlining the biological connectivity between terrestrial runoff and stream flow. [ABSTRACT FROM AUTHOR]

Density functional theory is used to study the effect of asymmetric in-plane strain on various BiInO3 phases. Structural relaxation is carried out to simulate the growth of coherently strained epitaxial films on (001) oriented orthorhombic perovskite substrates. The results are in particular analyzed with respect to commercially available substrates in order to assess the stabilization of new and fundamentally interesting BiInO3 phases. We find that a pyroxene-like Pcca phase is energetically more favorable than the bulk-like Pna21 structure on standard cubic substrate materials, such as SrTiO3. However, the presence of imaginary phonon modes suggests that this phase is dynamically instable. The bulk-like structure instead is stable over a wide range of lattice in-plane strain, but coherent growth requires substrates with unusually large lattice parameters. We suggest the use of lanthanate substrates in order to produce high-quality thin films of the bulk phase. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and finite element (FE) investigation into the local-overall buckling interaction behaviour of axially loaded cold-formed steel (CFS) channel section columns. Current design guidelines from the American Iron and Steel Institute (AISI) and the Australian and New Zealand Standards (AS/NZS) recommend the use of a non-dimensional strength curve for determining the axial capacity of such CFS channel section columns. This study has reviewed the accuracy of the current AISI (2016), AS/NZS (2018) and Eurocode (EN 1993-1-3) design guidelines for determining the axial capacity of CFS channel sections under local-overall buckling interaction failure. A total of 40 tests were conducted on CFS channel sections covering stub, short, intermediate, and slender columns with varying thicknesses. A nonlinear FE model was then developed and validated against the test results. The validated FE model was used to conduct a parametric study comprising 70 FE models to review the accuracy of the current design guidelines in accordance with AISI (2016), AS/NZS (2018) and Eurocode (EN 1993-1-3). It was found that the AISI (2016) and AS/NZS (2018) are conservative by 10 to 15% on average when determining the axial capacity of pin-ended CFS channel section columns undergoing local-overall buckling interaction. Eurocode (EN 1993-1-3) design rules were found to lead to considerably more conservative predictions of column axial load capacity for CFS channels.This paper has therefore proposed modifications to the current design rules of AISI (2016) and AS/NZS (2018). The accuracy of proposed design rules was verified using the FE analysis and test results of CFS channel section columns undergoing local-overall buckling interaction. [ABSTRACT FROM AUTHOR]

Hydrogen Evolution Reaction (HER) is an attractive technology for chemical conversion of energy. Replacement of platinum with inexpensive and stable electrocatalysts remains a major bottleneck hampering large-scale hydrogen production by using clean and renewable energy sources. Here, we report electrocatalytically active and ultra-stable Polymer-Derived Ceramics towards HER. We successfully prepared ultrathin silicon and carbon (Si–C) based ceramic systems supported on electrically conducting 2D reduced graphene oxide (rGO) nanosheets with promising HER activity by varying the nature and the composition of the ceramic with the inclusion of nitrogen, boron and oxygen. Our results suggest that oxygen-enriched Si-B-C-N/rGO composites (O-SiBCN/rGO) display the strongest catalytic activity leading to an onset potential and a Tafel slope of − 340 mV and ~ 120 mV dec−1 respectively. O-SiBCN/rGO electrodes display stability over 170 h with minimal increase of 14% of the overpotential compared to ~ 1700% for commercial platinum nanoparticles. Our study provides new insights on the performance of ceramics as affordable and robust HER catalysts calling for further exploration of the electrocatalytic activity of such unconventional materials. [ABSTRACT FROM AUTHOR]

Extreme differences between the sexes are usually explained by intense sexual selection on male weapons or ornaments. Sexually antagonistic genes, with a positive effect on male traits but a negative effect on female fitness, create a negative inter-sexual correlation for fitness (sexual conflict). However, such antagonism might not be apparent if sexually selected male traits are condition-dependent, and condition elevates female fitness. Here we reveal a surprising positive genetic correlation between male weaponry and female fecundity. Using mite lines that had previously been through 13 generations of selection on male weapons (fighting legs), we investigated correlated evolution in female fecundity. Females from lines under positive selection for weapons (up lines) evolved higher fecundity, despite evolving costly, thicker legs. This is likely because male mites have condition-dependent weaponry that increases our ability to indirectly select on male condition. Alleles with positive effects on condition in both sexes could have generated this correlation because: the up lines evolved a higher proportion of fighters and there were positive correlations between weapon size and the male morph and sex ratios of the offspring. This positive inter-sexual genetic correlation should boost the evolution of male weapons and extreme sex differences. [ABSTRACT FROM AUTHOR]

Accurately locating the foraging areas of diving marine predators is central to understanding their ecology and implementing conservation and management regulations. This study compares horizontal and vertical approaches of identifying seal foraging areas. We analysed GPS locations and dive data obtained from GPS/GSM tags fitted on eight grey seals (Halichoerus grypus) and nine harbour seals (Phoca vitulina). In the horizontal dimension, we used the First Passage Time to identify Area-Restricted Search (ARS) behaviour. In the vertical dimension, we used two dive criteria indicating benthic foraging behaviour: dive shape and vertical descent speed. The two approaches were spatially compared using the Index of Differences in Spatial Pattern. We found that the two approaches highlight similar hotspots when pooling all individuals of the same species. However, the degree of overlap varied considerably at the individual level. Some individuals performed most of their likely foraging dives (vertical dimension) in areas where they also displayed ARS behaviour (horizontal dimension), while others performed these dives both in and outside ARS zones. We suggest that comparing foraging areas detected from horizontal and vertical approaches (1) can strengthen the confidence in the efficiency of approaches to accurately spatialize the actual foraging effort of a diving predator at the scale of a colony (sampled with several individuals); and (2) provides more comprehensive insights into potential interindividual differences in foraging strategies as some divergent individual strategies may not be detected using only horizontal movements. [ABSTRACT FROM AUTHOR]

Objectives: We investigated the incidence of tuberculosis (TB) in patients with newly diagnosed oral cancer and analyzed the risk factors for TB development and mortality in oral cancer patients. Materials and methods: We used Taiwan's National Health Insurance Database to determine the incidence of TB and to analyze the risk factors for TB in patients newly diagnosed with oral cancer. From 2000 to 2011, we identified 40,327 oral cancer patients and the same number of subjects from the general population matched for sex, age, and comorbidities at a 1:1 ratio. Results: Compared with the matched cohort, oral cancer patients exhibited a higher risk for TB (adjusted hazard ratio (aHR) 2.36, 95% confidence interval (CI) 2.06–2.71). Age ≥ 50 (aHR 1.90, 95% CI 1.57–2.29), being male (aHR 1.98, 95% CI 1.36–2.89), having diabetes mellitus (aHR 1.31, 95% CI 1.05–1.64), alcohol use disorder (aHR 1.42, 95% CI 1.06–1.89), human immunodeficiency virus (HIV) (aHR 8.24, 95% CI 2.05–33.14), chemotherapy (aHR 1.41, 95% CI 1.15–1.72), and radiotherapy for oral cancer (aHR 1.92, 95% CI 1.57–2.36) were identified as independent risk factors for TB in oral cancer patients. Hyperlipidemia was an independent protective factor for TB in oral cancer patients. Conclusion: Old age, male sex, diabetes mellitus, alcohol use disorder, and HIV were independent risk factors for TB in patients with oral cancer. Clinical relevance: High-risk oral cancer patients should be regularly screened for TB, especially those in endemic areas. [ABSTRACT FROM AUTHOR]

The Red River, draining a 169,000 km2 watershed, is the second largest river in Viet Nam and constitutes the main source of water for a large percentage of the population of North Viet Nam. Here we present the results of an investigation into the spatial distribution and temporal dynamics of particulate and dissolved organic carbon (POC and DOC, respectively) in the Red River Basin. POC concentrations ranged from 0.24 to 5.80 mg C L−1 and DOC concentrations ranged from 0.26 to 5.39 mg C L−1. The application of the Seneque/Riverstrahler model to monthly POC and DOC measurements showed that, in general, the model simulations of the temporal variations and spatial distribution of organic carbon (OC) concentration followed the observed trends. They also show the impact of high population densities (up to 994 inhab km−2 in the delta area) on OC inputs in surface runoff from the different land use classes and from urban point sources. A budget of the main fluxes of OC in the whole river network, including diffuse inputs from soil leaching and runoff and point sources from urban centers, as well as algal net primary production and heterotrophic respiration was established using the model results. It shows the predominantly heterotrophic character of the river system and provides an estimate of CO2 emissions from the river of 330 Gg C year−1. This value is in reasonable agreement with the few available direct measurements of CO2 fluxes in the downstream part of the river network. [ABSTRACT FROM AUTHOR]

Aims: Our aim was to determine the effect of soil characteristics and root traits on soil aggregate stability at an inter- and intra-site scale in a range of agro-ecosystems. We also evaluated the effect of soil depth and the type of land use on aggregate stability.Methods: Soil aggregate stability, soil physicochemical properties and fine root traits were measured along land use gradients (from monocultures to agroforestry systems and forests), at two soil depths at four sites (Mediterranean and tropical climates) with contrasting soils (Andosol, Ferralsol, Leptosol and Fluvisol).Results: Aggregate stability was much lower in deep than in surface soil layers, likely linked to lower soil organic carbon (SOC) and lower root mass density (RMD). Locally, and consistently in all sites, land use intensification degrades soil aggregate stability, mainly in surface soil layers. Soil organic carbon, cation exchange capacity and root traits: water-soluble compounds, lignin and medium root length proportion were the most important drivers of aggregate stability at the inter-site level, whereas SOC, root mass and root length densities (RMD, RLD) were the main drivers at the intra-site level.Conclusions: Overall, the data suggest different controls on soil aggregate stability globally (soil) and locally (roots). Conversion from forests to agricultural land will likely lead to greater C losses through a loss of aggregate stability and increased soil erosion. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the association between obstructive sleep apnea (OSA) and ophthalmologic diseases, specifically glaucoma, nonarteritic anterior ischemic optic neuropathy (NAION), retinal vein occlusion (RVO), central serous chorioretinopathy (CSR), and floppy eyelid syndrome (FES), by performing a systematic review and meta-analysis of published studies. Methods: PubMed, Embase, and Scopus databases were searched for observational studies on OSA and its association with select ophthalmologic diseases. Data was pooled for random-effects modeling. The association between OSA and ophthalmologic diseases was summarized using an estimated pooled odds ratio with a 95 % confidence interval. Results: Relative to non-OSA subjects, OSA subjects have increased odds of diagnosis with glaucoma (pooled odds ratio (OR) = 1.242; P < 0.001) and floppy eyelids syndrome (pooled OR = 4.157; P < 0.001). In reverse, the overall pooled OR for OSA was 1.746 ( P = 0.002) in the glaucoma group, 3.126 ( P = 0.000) in the NAION group, and 2.019 ( P = 0.028) in the CSR group. For RVO, one study with 5965 OSA patients and 29,669 controls demonstrated a 1.94-fold odds increase in OSA patients. Conclusions: Our results suggest significant associations between OSA and glaucoma, NAION, CSR, and FES. Screening for OSA should be considered in patients with glaucoma, NAION, CSR, or FES. [ABSTRACT FROM AUTHOR]

Dynamic magnetic resonance imaging (MRI) allows real-time characterization of upper airway collapse in sleeping subjects with obstructive sleep apnea (OSA). The aim of our study was to use sleep MRI to compare differences in upper airway collapse sites between BMI-matched subjects with mild OSA and severe OSA. This is a prospective, nested case-control study using dynamic sleep MRI to compare 15 severe OSA subjects (AHI >40) and 15 mild OSA (AHI <10) subjects, who were matched for BMI. Upper airway imaging was performed on sleeping subjects in a 3.0 T MRI scanner. Sleep MRI movies were used by blinded reviewers to identify retropalatal (RP), retroglossal (RG), and lateral pharyngeal wall (LPW) airway collapse. Mean AHI in the severe OSA group was 70.3 ± 23 events/h, and in the mild group was 7.8 ± 1 events/h ( p < 0.001). All mild and severe OSA subjects demonstrated retropalatal airway collapse. Eighty percent in the mild group showed single-level RP collapse ( p < 0.001). All subjects in the severe group showed multi-level collapse: RP + LPW ( n = 9), RP + RG + LPW ( n = 6). All severe OSA subjects showed LPW collapse, as compared with three subjects in the mild group ( p < 0.001). LPW collapse was positively associated with AHI in simple regression analysis ( β = 51.8, p < 0.001). In conclusion, severe OSA patients present with more lateral pharyngeal wall collapse as compared to BMI-matched mild OSA patients. [ABSTRACT FROM AUTHOR]

The mechanical characteristics of various sedimentary stones significantly depend on the water content, where 70 % loss of their mechanical strengths can be observed when saturated by water. Furthermore, the clay fraction has been shown to be a key factor of their hydro-mechanical behaviour since it governs for instance the hydric dilation. This work aims at investigating the correlations between the clay mineral content and the mechanical weakening experienced by limestones when interacting with water. The experimental characterization focuses on five different limestones that exhibit very different micro-structures. For each of them, we present the determination of clay mineral composition, the sorption isotherm curve and the dependences of tensile and compressive strengths on the water content. It emerges from these results that, first, the sorption behaviour is mainly governed by the amount of smectite layers which exhibit the larger specific area and, second, the rate of mechanical strength loss depends linearly on the sorption capacity. Indeed, the clay fraction plays the role of a retardation factor that delays the appearance of capillary bridges as well as the mechanical weakening of stones. However, no correlation was evidenced between the clay content and the amplitude of weakening. Since the mechanisms whereby the strength decreases with water content are not clearly established, these results would help to discriminate between various hypothesis proposed in the literature. [ABSTRACT FROM AUTHOR]

Autotomy and regrowth of a body part occurs in many animal species. It is costly to regrow the limb and there are often additional long-term costs in, for example, limb strength, foraging efficiency and even mating success. In the fiddler crab Uca mjoebergi, 7 % of males have autotomized and regrown their large claw at some point in their lives. Previous work has shown that there is a great disadvantage to having a regenerated claw. While these males are able to attract mate-searching females to visit them, none of the 84 males observed to have mated in previously collected data had regenerated claws. Since females' final mate choice is based on burrow structure, it was assumed that males with regenerated claws had poorer burrows. Here we show that, by finding only three cases of a female mating with a regenerated claw male, that there is, in fact, no mating disadvantage to having a regenerated claw. We also show that the burrows of males with regenerated claws are no different than those of orginal-clawed males. This is a very clear reminder that sample size matters, especially when dealing with rare events. [ABSTRACT FROM AUTHOR]

Purpose: Land use change and the associated acceleration of soil erosion have increased sediment supply to rivers worldwide. To effectively manage sediment loads, it is important to understand sediment dynamics. Fallout radionuclides (i.e. Be-7, excess Pb-210, Cs-137) separately provide spatial and temporal sediment source information. However, their combined application has been limited by an assumption that subsurface sources do not receive Be fallout. Here, we examine this assumption and investigate the utility of combining these radionuclides to simultaneously model spatial and temporal sediment source dynamics. Materials and methods: Soil and subsurface material were sampled to characterize potential sediment sources in a 12-km catchment in northern Laos. This included material that was directly sampled from surface and subsurface sources ( n = 65) and also in situ sediment source samples that were collected in ephemeral flow on hillslopes ( n = 19). Suspended sediment ( n = 16) was sampled at two monitoring stations. A distribution modelling approach quantified the relative contributions of surface and subsurface sources, as well as the proportion of material labelled with Be. The results from these two end-member models were compared to a four end-member model examining contributions from recently eroded surface, recently eroded subsurface, re-suspended surface and re-suspended subsurface sources. Results and discussion: Approximately 80 % of sediment was modelled to be supplied by sources labelled with Be. Subsurface sources were modelled to contribute ~75 % of sediment. Accordingly, there was ~55 % more sediment modelled from subsurface sources than expected if subsurface sources were sheltered from Be fallout. Differences between subsoil and Be-labelled source contributions modelled by the two and four end-member models were, with one exception (0.3 %), within the range of model uncertainty, further supporting the existence of re-suspended subsurface sources. At an upstream sampling location (S4), surface sources contributed the majority of sediment (55 %) whereas subsurface sources dominated the supply of sediment downstream (S10-74 %). Importantly, re-suspended subsurface sources, labelled with Be, were a significant sediment source at the catchment outlet (S10-60 %) during the investigated event. Conclusions and perspectives: This study demonstrates the utility of combining multiple radionuclides when investigating spatial and temporal sediment source dynamics in tropical, ephemeral catchments. In the future, this approach should be tested with larger source datasets during the entire wet season and in larger catchments. This research furthers our understanding of sediment propagation in tropical catchments, contributing to the implementation of efficient soil conservation measures to reduce the deleterious effects of suspended sediment loads. [ABSTRACT FROM AUTHOR]

Consumption of water polluted by faecal contaminants is responsible for 2 million deaths annually, most of which occur in developing countries without adequate sanitation. In tropical aquatic systems, streambeds can be reservoirs of persistent pathogenic bacteria and high rainfall can lead to contaminated soils entering streams and to the resuspension of sediment-bound microbes in the streambed. Here, we present a novel method using fallout radionuclides (Be and Pb) to estimate the proportions of Escherichia coli, an indicator of faecal contamination, associated with recently eroded soil particles and with the resuspension of streambed sediments. We show that using these radionuclides and hydrograph separations we are able to characterize the proportion of particles originating from highly contaminated soils and that from the resuspension of particle-attached bacteria within the streambed. We also found that although overland flow represented just over one tenth of the total flood volume, it was responsible for more than two thirds of the downstream transfer of E. coli. We propose that data obtained using this method can be used to understand the dynamics of faecal indicator bacteria (FIB) in streams thereby providing information for adapted management plans that reduce the health risks to local populations.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Pentameric ligand-gated ion channels mediate signal transduction through conformational transitions between closed-pore and open-pore states. To stabilize a closed conformation of GLIC, a bacterial proton-gated homolog from Gloeobacter violaceus whose open structure is known, we separately generated either four cross-links or two single mutations. We found all six mutants to be in the same 'locally closed' conformation using X-ray crystallography, sharing most of the features of the open form but showing a locally closed pore as a result of a concerted bending of all of its M2 helices. The mutants adopt several variant conformations of the M2-M3 loop, and in all cases an interacting lipid that is observed in the open form disappears. A single cross-linked mutant is functional, according to electrophysiology, and the locally closed structure of this mutant indicates that it has an increased flexibility. Further cross-linking, accessibility and molecular dynamics data suggest that the locally closed form is a functionally relevant conformation that occurs during allosteric gating transitions. [ABSTRACT FROM AUTHOR]

Improving access to clean water has the potential to make a major contribution toward poverty reduction in rural communities of Lao P.D.R. This study focuses on stream water quality along a Mekong basin tributary, the Houay Xon that flows within a mountainous, mosaic land-use catchment of northern Lao P.D.R. To compare direct water quality measurements to the perception of water quality within the riparian population, our survey included interviews of villagers. Water quality was found to vary greatly depending on the location along the stream. Overall, it reflected the balance between the stream self-cleaning potential and human pressure on the riparian zone: (i) high bacteria and suspended load levels occurred where livestock are left to free-range within the riparian zone; (ii) very low oxygen content and high bacteriological contamination prevailed downstream from villages; (iii) high concentrations of bacteria were consistently observed along urbanized banks; (iv) low oxygen content were associated with the discharge of organic-rich wastewater from a small industrial plant; (v) very high suspended load and bacteria levels occurred during flood events due to soil erosion from steep cultivated hill slopes. Besides these human induced pollutions we also noted spontaneous enrichments in metals in wetland areas fed by dysoxic groundwater. These biophysical measurements were in agreement with the opinions expressed by the majority of the interviewees who reported poor and decreasing water quality in the Houay Xon catchment. Based on our survey, we propose recommendations to improve or maintain stream water quality in the uplands of northern Lao P.D.R. [ABSTRACT FROM AUTHOR]

To establish the incidence and long-term prognosis of iatrogenic gas embolism. This was a prospective inception cohort. We included all consecutive adults with proven iatrogenic gas embolism admitted to the sole referral academic hyperbaric center in Paris. Treatment was standardized as one hyperbaric session at 4 ATA for 15 min followed by two 45-min plateaus at 2.5 then 2 ATA. Inspired fraction of oxygen was set at 100% during the entire dive. Primary endpoint was 1-year mortality. All patients had evaluation by a neurologist, visual field tested by Goldman kinetic perimetry and brain MRI or CT scan at 6 months and 1 year. From January 1993 to August 2004, 125 of 4,727,496 hospitalizations had proven iatrogenic gas embolism. The crude mortality was 25/119 (21%) at 1 year. Cardiac arrest at time of accident and ICU admission, and SAPS II of 33 or more were independent prognostic factors of 1-year mortality (OR = 4.39, 95% CI 1.46–12.20 and OR = 6.30, 1.71–23.21, respectively). Among ICU survivors, independent predictors of 1-year mortality were age (OR = 1.07, 1.01–1.14), Babinski sign (OR = 6.58, 1.14–38.20) and acute kidney failure (OR = 8.09, 1.28–51.21). Focal motor deficits (OR = 12.78, 3.98–41.09) and Babinski sign (OR = 6.76, 2.24–20.33) on ICU admission, and duration of mechanical ventilation of 5 days or more (OR = 15.14, 2.92–78.52) were independent predictors of long-term sequels. Gas embolism complicates 2.65 per 100,000 hospitalizations, and is associated with high mortality and morbidity. Babinski sign on ICU admission is associated with poor prognosis. [ABSTRACT FROM AUTHOR]

Whereas neuroblastoma (NB) with MYCN amplification presents a poor prognosis, no single marker allows to reliably predict outcome in tumours without MYCN amplification. We report here an extensive analysis of 147 NB samples at diagnosis, without MYCN amplification, by chromosomal comparative genomic hybridisation (CGH), providing a comprehensive overview of their genomic imbalances. Comparative genomic hybridisation profiles showed gains or losses of entire chromosomes (type 1) in 71 cases, whereas partial chromosome gains or losses (type 2), including gain involving 17q were observed in 68 cases. Atypical profiles were present in eight cases. A type 1 profile was observed more frequently in localised disease (P<0.0001), and in patients of less than 12 months at diagnosis (P<0.0001). A type 2 genomic profile was associated with a higher risk of relapse in the overall population (log-rank test; P<0.0001), but also in the subgroup of patients with localised disease (log-rank test, P=0.007). In multivariate analysis, the genomic profile was the strongest independent prognostic factor. In conclusion, the genomic profile is of prognostic impact in patients without MYCN amplification, making it a help in the management of low-stage NB. Further studies using higher-resolution CGH are needed to better characterise atypical genomic alterations. [ABSTRACT FROM AUTHOR]

Multiple questionnaires completed over the semester by 514 students enrolled in a first year psychology course reveal that no single pattern of reliance on print, online, or in-person resources guarantees a high mark. Analyses of the reported and measured frequency of use of various resources correlated against students’, performance on both individual assessments and their final marks suggests that students employ a range of strategies in their use of class resources. They tend to rely on their textbooks, Web-based lecture notes, and online quizzes, but their final marks are more strongly determined by their university entrance scores than by their resource use strategy, their sex, or whether or not English is their first language. The data suggest that students adapt their learning strategies to the resources available, with an apparent emphasis on learning what will be assessed rather than exploring for understanding. Importantly, the results argue that investment in development of educational technologies – and students’, use of educational technologies – must be informed by empirical data concerning its impact on the efficiency and quality of learning. [ABSTRACT FROM AUTHOR]

Previous research has generally failed to find a relation between the way students approach the task of studying and their exam grades. The present study investigated why it is that a deep approach to studying, which has been shown to result in a higher quality of learning, does not consistently result in higher exam grades. The participants in the study were 49 third-year psychology students. They completed questionnaires that assessed approaches to studying, motivation, and intelligence. Their final exam marks, along with indicators of the quality of their final exam responses and the quantity of information reproduced in the final exam were used as indicators of academic performance. The results showed that the deep study approach was linearly related to the quality of exam responses, but quadratically related to the quantity of information reproduced. The use of the deep approach was no more effective in facilitating high exam marks for questions that emphasised understanding of the study material than for questions that emphasised reproduction of it. Taken together, these findings suggest that students who use high levels of the deep approach fail to consistently achieve higher exam grades because of deficiencies in the quantity of their responses, rather than because of the insensitivity of exams to students' understanding of the study material. [ABSTRACT FROM AUTHOR]

With PCR products as probes, we have cloned two new cry-type genes from Bacillus thuringiensis subsp. wuhanensis. The deduced amino acid sequence of the first clone is 77.3% identical to Cry1Ga1. The deduced protein sequence of the second clone is 69.8–78.7% identical to that of Cry1B group. The nomenclature assignment of these two clones is, therefore, named Cry1Gb1 and Cry1Bd1, respectively. The Cry1Bd1 is toxic to Plutella xylostella larvae, and the Cry1Gb1 is toxic to Pieris rapae larvae. [ABSTRACT FROM AUTHOR]

Background. Exogenous surfactant treatment of hyaline membrane disease is known to modify the pattern of radiological changes on the chest radiograph. Objectives. To analyse and attempt to explain the radiological changes observed after exogenous surfactant treatment. Materials and methods. Thirty-nine premature infants with typical hyaline membrane disease. Results. Transient asymmetrical clearing with better aeration of the right lung in the absence of malposition of the tip of the endotracheal tube was observed in nine cases (23 %). This asymmetry was patchy in one case. It was due to a complication of mechanical ventilation in three cases [pneumothorax ( n = 2) and pneumomediastinum ( n = 1)]. In the other six cases, asymmetrical clearing could be related to the anatomical position of the right main bronchus, which facilitates distribution of surfactant to the right lung. However, the course of these premature infants was similar to that of infants with symmetrical chest radiological findings after treatment. Conclusions. Asymmetrical clearing of chest radiographs, sometimes patchy, after surfactant treatment requires exclusion of pneumothorax or infection but has no influence on clinical outcome. [ABSTRACT FROM AUTHOR]

Infraspecific genetic differentiation was analysed in two tetraploid annual bromegrasses, Bromus lanceolatus (from N Africa) and B. hordeaceus (from N Africa and France). Genetic analysis of populations was based on allozyme polymorphisms at 17 loci. Different fixed heterozygous phenotypes were scored in both species, according to their allopolyploid origin. In N Africa, more variation occurred among populations of B. lanceolatus than of B. hordeaceus. The variation was not randomly distributed among populations of both species. In B. lanceolatus, differentiation was correlated with climatic variables rather than with geographic distance between populations. Higher correlation of genetic differentiation with geographic distance occurred in B. hordeaceus, particularly at large geographic scale, between French and N African populations. Within each region, the populations appeared weakly genetically differentiated, even when belonging to different subspecies. [ABSTRACT FROM AUTHOR]

The enzymatic spectra of Typha angustifolia, T. latifolia and their hybrids were examined by disc electrophoresis for three enzymatic systems: esterases, alcohol deshydrogenase, and glutamate deshydrogenase. The intermediate position of the hybrids is confirmed. The study of alcohol deshydrogenase reveales the existence of an intraspecific variability in T. angustifolia between individuals from the Massif Armoricain in France and Dellys in Algeria. [ABSTRACT FROM AUTHOR]

The author would like to correct the Fig. 4 of the published article. [ABSTRACT FROM AUTHOR]