Dried blood spots can help decrease the burden on patients dually infected with multidrug-resistant tuberculosis and HIV

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The spatio-temporal pattern of Argentine shortfin squid Illex argentinus abundance in the southwest Atlantic

The Argentine shortfin squid (Illex argentinus) is a common neritic species occurring in waters off Brazil, Uruguay, Argentina, and the Falkland/Malvinas Islands in the southwest Atlantic. Illex argentinus is the most important fished cephalopod species in the area and plays a significant role in the ecosystem. It is object of major fisheries using both trawlers (mostly from European countries) and jigging vessels (mainly from Asian countries) and estimated total annual average catch for the last 15 years (1988-2003) is about 700 000 tons. The present paper aims to develop predictive models of squid abundance in relation to physical and environmental conditions, models that could ultimately be applied to fishery forecasting. Fishery and biological data collected by scientific observers aboard commercial trawlers between 1988 and 2003 were analysed in relation to physical and environmental factors to establish the spatio-temporal pattern of the species’ distribution and quantify the influence of environmental variables (e.g. SST, depth) on local abundance. The data included 26 168 fishing haul records, of which 11 103 were positive for Illex. CPUE (Catch Per Unit Effort, kg h−1) was used as abundance index. The analyses were based on time-series maps created using Geographical Information Systems (GIS). GIS maps showed that highest CPUE values were recorded during the first four months of the year (the Austral summer-autumn), with peak values higher than 5000 kg h−1 mainly located within 42◦ S, 46◦ S and MN (North part of Malvinas/Falkland) areas. Generalised additive models (GAMs) were used to describe variation in Illex argentinus abundance in relation to geographical and environmental variables. The presence/absence (PA) of Illex and its abundance (CPUE) in areas of presence were modelled separately. Predictors retained in the optimal models included SST, latitude, longitude, month, average fishing depth and year. Both models suggest a clear seasonal effect: maximum catchability was found during March (PA model) and the maximum abundances were found during the first quarter of the year (CPUE model). GAM models also demonstrated that higher catches and maturity of squid were related, in general terms, to warmer and deeper water.Abondance spatio-temporelle du calmar Illex argentinus dans l’Atlantique Sud. L’encornet rouge argentin (Illex argentinus) est une espèce néritique commune de l’Atlantique Sud-Ouest présente dans les eaux du Brésil, de l’Uruguay de l’Argentine et des îles Malouines (Falklands). Illex argentinus est la principale espèce de céphalopode exploitée dans cette région où elle joue un rôle majeur dans l’écosystème. L’espèce est pêchée par d’importantes flottilles de chalutiers (principalement de pays européens) et aux turluttes industrielles (de pays asiatiques) pour une production annuelle de 700 000 t en moyenne sur les 15 dernières années (1988-2003). Cet article présente des modèles prédictifs de l’abondance en fonction des facteurs physiques et environnementaux ; modèles qui pourraient à terme être appliqués à la gestion des pêches. Les données de capture et les paramètres biologiques récoltés, grâce à des observateurs embarqués, de 1988 à 2003, ont été analysées en relation avec les facteurs physiques pour préciser les variations spatio-temporelles de répartition et quantifier l’effet de la température et de la profondeur sur l’abondance. Le jeu de données porte sur 26 168 traits de pêche dont 11 103 comportant des captures d’Illex. Les captures par unité d’effort (CPUE en kg h−1) sont utilisées comme indice d’abondance et les analyses utilisent des séries de cartes, créées avec un système d’information géographique (SIG). Les valeurs les plus élevées de CPUE sont enregistrées durant les quatre premiers mois de l’année (l’été et l’automne austral) avec un pic dépassant 5000 kg h−1 localisé entre 42◦ S et 46◦ S dans la partie Nord desMalouines. Les modèles additifs généralisés (GAM) ont servi à décrire les variations d’abondance en fonction des variables géographiques et environnementales. La présence ou l’absence de la ressource est modélisée séparément de l’abondance. Les modèles optimaux retiennent comme variables explicatives la température, la latitude, la longitude, le mois, la profondeur et l’année. Les deux modèles indiquent un effet saisonnier net: la capturabilité est maximale en mars (présence/absence) et l’abondance (CPUE) est la plus élevée durant le premier trimestre. Les modèles additifs généralisés montrent également que les captures les plus élevées d’animaux à maturité sont associées à des eaux plus tièdes et des secteurs plus profonds

Ecological Modeling of Aedes aegypti (L.) Pupal Production in Rural Kamphaeng Phet, Thailand

Background - Aedes aegypti (L.) is the primary vector of dengue, the most important arboviral infection globally. Until an effective vaccine is licensed and rigorously administered, Ae. aegypti control remains the principal tool in preventing and curtailing dengue transmission. Accurate predictions of vector populations are required to assess control methods and develop effective population reduction strategies. Ae. aegypti develops primarily in artificial water holding containers. Release recapture studies indicate that most adult Ae. aegypti do not disperse over long distances. We expect, therefore, that containers in an area of high development site density are more likely to be oviposition sites and to be more frequently used as oviposition sites than containers that are relatively isolated from other development sites. After accounting for individual container characteristics, containers more frequently used as oviposition sites are likely to produce adult mosquitoes consistently and at a higher rate. To this point, most studies of Ae. aegypti populations ignore the spatial density of larval development sites. Methodology - Pupal surveys were carried out from 2004 to 2007 in rural Kamphaeng Phet, Thailand. In total, 84,840 samples of water holding containers were used to estimate model parameters. Regression modeling was used to assess the effect of larval development site density, access to piped water, and seasonal variation on container productivity. A varying-coefficients model was employed to account for the large differences in productivity between container types. A two-part modeling structure, called a hurdle model, accounts for the large number of zeroes and overdispersion present in pupal population counts. Findings - The number of suitable larval development sites and their density in the environment were the primary determinants of the distribution and abundance of Ae. aegypti pupae. The productivity of most container types increased significantly as habitat density increased. An ecological approach, accounting for development site density, is appropriate for predicting Ae. aegypti population levels and developing efficient vector control program

Cave spiders choose optimal environmental factors with respect to the generated entropy when laying their cocoon

The choice of a suitable area to spiders where to lay eggs is promoted in terms of Darwinian fitness. Despite its importance, the underlying factors behind this key decision are generally poorly understood. Here, we designed a multidisciplinary study based both on in-field data and laboratory experiments focusing on the European cave spider Meta menardi (Araneae, Tetragnathidae) and aiming at understanding the selective forces driving the female in the choice of the depositional area. Our in-field data analysis demonstrated a major role of air velocity and distance from the cave entrance within a particular cave in driving the female choice. This has been interpreted using a model based on the Entropy Generation Minimization - EGM - method, without invoking best fit parameters and thanks to independent lab experiments, thus demonstrating that the female chooses the depositional area according to minimal level of thermo-fluid-dynamic irreversibility. This methodology may pave the way to a novel approach in understanding evolutionary strategies for other living organisms

Neoadjuvant nivolumab and nivolumab plus ipilimumab induce (near-) complete responses in patients with head and neck squamous cell carcinoma:The IMCISION trial

BackgroundNivolumab (NIVO) alone or with ipilimumab (COMBO) immune checkpoint blockade (ICB) prior to curative surgery has shown promising results in multiple tumor types. We completed a phase Ib/II study with neoadjuvant NIVO or COMBO in resectable head and neck squamous cell carcinoma (HNSCC) and show safety, efficacy and correlative biomarker results.Methods32 stage II-IVB HNSCC patients indicated for curative (salvage) surgery were treated with NIVO (240mg, weeks 1&3, N=6) or NIVO (240mg, weeks 1&3) + IPI (1mg/kg, week 1, N=26) prior to surgery in week 5. Imaging was performed at baseline and week 4. AEs were reported in terms of CTCAE. Pathological response (pR) was defined as % change in viable tumor cells from baseline to on-treatment; ≥90% pR was considered (near-) complete response (pCR). WES and RNAseq were performed on paired tumor biopsies.Results32 (31 HPV-negative) patients started treatment (stage II n=3, III n=8, IVA-B n=11, recurrent disease n=10). 6 patients included with recurrent disease had had previous (C)RT. 1 patient discontinued ICB after one course due to patient’s preference. Surgery was not postponed in any patient. 3/32 patients did not undergo surgery: 1 due to unresectable PD and 2 due to reasons unrelated to ICB or disease. Grade 3-4 irAEs in 11/32 patients were well manageable. (Near-)pCR in the primary tumor was seen in 9/29 evaluable patients (31%). Another 31% of patients had 20-89% pR. At 14 months median FU, RFS for patients with (near-)pCR was 100%, significantly better than patients with <90% pR (p=<0.05). Metabolic response assessment with FDG-PET (week 4) was able to identify (near-)pCRs. A baseline AID/APOBEC-associated tumor mutational profile was correlated with (near)pCR (p=<0.05). Finally, (near)pCR tumors were characterized by a decrease in hypoxia gene expression after ICB.ConclusionsNeoadjuvant ICB was feasible in HNSCC and induced (near)pCR in 31% of evaluable patients at time of surgery, which was accompanied by 100% RFS. Baseline AID/APOBEC-related mutations, on-treatment FDG-PET and resolution of hypoxia need future validation to discover their potential role as biomarkers for (near)pCR after ICB in HNSCC

New Insights Into Legacy Phosphorus From Fractionation of Streambed Sediment

Streambed and lake sediment was studied in Savjaan, a eutrophic mesoscale catchment (722 km(2)) in central Sweden. Triplicate sediment cores from five lakes and nine streams, ranging from headwater to fourth order, were sampled. The sediment was analyzed with a sequential extraction method, where six different phosphorus (P) fractions were measured. The results showed that streambed sediments store considerable amounts of P and in some cases have comparable P contents (g/kg DW) to lake sediment. Land use, soil type, and drainage area (location in the catchment) had a significant effect on the different P fractions found in surficial sediments. Sediment from lakes and forested headwater streams generally had high proportions of organic P and iron bound P. In larger streams located in agricultural areas on clay soils closer to the catchment outlet, with dense sediment and a relatively low proportion of organic matter, P was to a larger extent bound to calcium. Streambed sediment may be an important catchment scale P store and should be considered when modeling catchment P dynamics. The large stores of streambed legacy P should also be considered when performing ditch maintenance to avoid unnecessary mobilization of bioavailable P

Resource Quantity Affects Benthic Microbial Community Structure and Growth Efficiency in a Temperate Intertidal Mudflat

Estuaries cover <1% of marine habitats, but the carbon dioxide (CO2) effluxes from these net heterotrophic systems contribute significantly to the global carbon cycle. Anthropogenic eutrophication of estuarine waterways increases the supply of labile substrates to the underlying sediments. How such changes affect the form and functioning of the resident microbial communities remains unclear. We employed a carbon-13 pulse-chase experiment to investigate how a temperate estuarine benthic microbial community at 6.5°C responded to additions of marine diatom-derived organic carbon equivalent to 4.16, 41.60 and 416.00 mmol C m−2. The quantities of carbon mineralized and incorporated into bacterial biomass both increased significantly, albeit differentially, with resource supply. This resulted in bacterial growth efficiency increasing from 0.40±0.02 to 0.55±0.04 as substrates became more available. The proportions of diatom-derived carbon incorporated into individual microbial membrane fatty acids also varied with resource supply. Future increases in labile organic substrate supply have the potential to increase both the proportion of organic carbon being retained within the benthic compartment of estuaries and also the absolute quantity of CO2 outgassing from these environments

Predicting the exposure of diving grey seals to shipping noise.

There is high spatial overlap between grey seals and shipping traffic, and the functional hearing range of grey seals indicates sensitivity to underwater noise emitted by ships. However, there is still very little data regarding the exposure of grey seals to shipping noise, constraining effective policy decisions. Particularly, there are few predictions that consider the at-sea movement of seals. Consequently, this study aimed to predict the exposure of adult grey seals and pups to shipping noise along a three-dimensional movement track, and assess the influence of shipping characteristics on sound exposure levels. Using ship location data, a ship source model, and the acoustic propagation model, RAMSurf, this study estimated weighted 24-h sound exposure levels (10-1000 Hz) (SELw). Median predicted 24-h SELw was 128 and 142 dB re 1 μPa2s for the pups and adults, respectively. The predicted exposure of seals to shipping noise did not exceed best evidence thresholds for temporary threshold shift. Exposure was mediated by the number of ships, ship source level, the distance between seals and ships, and the at-sea behaviour of the seals. The results can inform regulatory planning related to anthropogenic pressures on seal populations

Influence of environmental parameters on movements and habitat utilization of humpback whales (Megaptera novaeangliae) in the Madagascar breeding ground

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Royal Society Open Science 3 (2016): 160616, doi:10.1098/rsos.160616.Assessing the movement patterns and key habitat features of breeding humpback whales is a prerequisite for the conservation management of this philopatric species. To investigate the interactions between humpback whale movements and environmental conditions off Madagascar, we deployed 25 satellite tags in the northeast and southwest coast of Madagascar. For each recorded position, we collated estimates of environmental variables and computed two behavioural metrics: behavioural state of ‘transiting’ (consistent/directional) versus ‘localized’ (variable/non-directional), and active swimming speed (i.e. speed relative to the current). On coastal habitats (i.e. bathymetry < 200 m and in adjacent areas), females showed localized behaviour in deep waters (191 ± 20 m) and at large distances (14 ± 0.6 km) from shore, suggesting that their breeding habitat extends beyond the shallowest waters available close to the coastline. Males' active swimming speed decreased in shallow waters, but environmental parameters did not influence their likelihood to exhibit localized movements, which was probably dominated by social factors instead. In oceanic habitats, both males and females showed localized behaviours in shallow waters and favoured high chlorophyll-a concentrations. Active swimming speed accounts for a large proportion of observed movement speed; however, breeding humpback whales probably exploit prevailing ocean currents to maximize displacement. This study provides evidence that coastal areas, generally subject to strong human pressure, remain the core habitat of humpback whales off Madagascar. Our results expand the knowledge of humpback whale habitat use in oceanic habitat and response to variability of environmental factors such as oceanic current and chlorophyll level.Funding was provided by Total Foundation to NeuroPSI, and by individuals and foundations to the WCS Ocean Giants Program

Modeling the vacuolar storage of malate shed lights on pre- and post-harvest fruit acidity

Background: Malate is one of the most important organic acids in many fruits and its concentration plays a critical role in organoleptic properties. Several studies suggest that malate accumulation in fruit cells is controlled at the level of vacuolar storage. However, the regulation of vacuolar malate storage throughout fruit development, and the origins of the phenotypic variability of the malate concentration within fruit species remain to be clarified. In the present study, we adapted the mechanistic model of vacuolar storage proposed by Lobit et al. in order to study the accumulation of malate in pre and postharvest fruits. The main adaptation concerned the variation of the free energy of ATP hydrolysis during fruit development. Banana fruit was taken as a reference because it has the particularity of having separate growth and post-harvest ripening stages, during which malate concentration undergoes substantial changes. Moreover, the concentration of malate in banana pulp varies greatly among cultivars which make possible to use the model as a tool to analyze the genotypic variability. The model was calibrated and validated using data sets from three cultivars with contrasting malate accumulation, grown under different fruit loads and potassium supplies, and harvested at different stages. Results: The model predicted the pre and post-harvest dynamics of malate concentration with fairly good accuracy for the three cultivars (mean RRMSE = 0.25-0.42). The sensitivity of the model to parameters and input variables was analyzed. According to the model, vacuolar composition, in particular potassium and organic acid concentrations, had an important effect on malate accumulation. The model suggested that rising temperatures depressed malate accumulation. The model also helped distinguish differences in malate concentration among the three cultivars and between the pre and post-harvest stages by highlighting the probable importance of proton pump activity and particularly of the free energy of ATP hydrolysis and vacuolar pH. Conclusions: This model appears to be an interesting tool to study malate accumulation in pre and postharvest fruits and to get insights into the ecophysiological determinants of fruit acidity, and thus may be useful for fruit quality improvement. (Résumé d'auteur