Miracle-dz/UniFAR-FTUs huggingface dataset:
Changes in latitude and dominant diazotrophic community alter N2 fixation

ABSTRACT: The contribution of planktonic diazotrophs to the overall N budget is a key unknown in the eastern Indian Ocean. Here we investigated the relationships between dissolved inorganic nutrients, phytoplankton pigment composition, microbial community structure, nitrogen fixation rates and the δ15N of fractionated zooplankton samples along the shelf break of Western Australia (32° to 12° S) in September 2012. Bulk nitrogen fixation rates declined from 4.8 nmol l−1 h−1 in the colder and more saline sub-tropical waters at higher latitudes to 1.5 nmol l−1 h−1 in the warmer and fresher Timor Sea at lower latitudes. A regional bloom of Trichodesmium was identified between 13° and 9° S in the Timor Sea. Trichodesmium-specific N2 fixation rates were 0.05 ± 0.01 nmol colony−1 h−1. Highest dissolved inorganic nitrogen (DIN) concentrations occurred at the highest NH4+:NO3− ratios, thereby deviating from the paradigm that greater DIN concentrations come primarily from increased NO3− through advection, mixing or upwelling. Both the microplankton and nanoflagellate fraction declined significantly in warmer waters, with higher DIN concentrations but decreasing % NO3−. A clear increase in the prokaryotic diagnostic pigment zeaxanthin was seen with increasing temperatures from higher to lower latitudes. The microbial community, measured using automated ribosomal intergenic spacer analysis (ARISA), clustered strongly according to the water mass biogeochemistry including temperature, salinity, DIN and phosphate concentrations (p < 0.001). Isotope analysis suggested that injections of low δ15N from N2 fixation lowered the zooplankton δ15N signature of animals up to ~500 μm in size and that nearly 47% of the fixed nitrogen was used by zooplankton (≤500 μm fraction) in the Timor Sea.
Spin Hall magnetoresistance in antiferromagnet/normal metal bilayers

We investigate the emergence of spin Hall magnetoresistance in a magnetic bilayer composed of a normal metal adjacent to an antiferromagnet. Based on a recently derived drift‐diffusion equation, we show that the resistance of the bilayer depends on the relative angle between the direction transverse to the current flow and the Néel order parameter. While this effect presents striking similarities with the spin Hall magnetoresistance recently reported in ferromagnetic bilayers, its physical origin is attributed to the anisotropic spin relaxation of itinerant spins in the antiferromagnet.
Energy efficient Dijkstra-based weighted sum minimization routing protocol for WSN

Wireless sensor networks (WSNs) consist of several wireless sensor nodes which have limited transmission power and processing capabilities. Hierarchical cluster-based routing protocols are considered an efficient technique to route data from sensor nodes to base station. This paper proposes a scheme which considers K-means clustering in cluster formation phase and calculates a weight function for the cluster head selection process. Moreover, it considers an optimal fixed packet size with respect to radio parameters and channel conditions of the transceiver. In data transmission phase, it implements a multiobjective weight function as a link cost using traditional Dijkstra algorithm. This technique results in balanced and efficient energy consumption of nodes within the network. Simulation results show that proposed scheme is better than the CERP and TEEN routing protocol in terms of energy conservation of nodes in the network and increases the throughput of the overall system. It also indicates high scalability and packet delivery rate due to the efficient use of energy in the system.
Les facteurs sous-jacents au transfert des compétences informatiques construites par les futurs maîtres du primaire sur le plan de l’intervention éducative

Cet article presente les resultats de deux enquetes menees aupres d’enseignants du primaire et d’etudiants du programme de formation initiale a l’enseignement au prescolaire et au primaire de l’Universite de Sherbrooke. Les chercheurs font d’abord etat de la documentation scientifique relative a l’identification des facteurs qui favorisent ou inhibent l’integration des TIC en enseignement, tant chez les enseignants chevronnes que chez les novices. Ils examinent ensuite l’impact eventuel des effets de modelage de la formation pratique sur la reproduction des modeles actuels de recours a ces technologies. Enfin, ils s’interrogent sur la probabilite de changer les pratiques en fonction de la stabilite des modeles d’intervention educative preconises en formation initiale a l’enseignement et dans les milieux de pratique.
MOCVD growth of GaAsP on Si for tandem solar cell application

In this paper, the crystal growth of GaAsP on Si substrate for solar cell application and the characteristics of GaAsP/Si monolithic tandem solar cells are described. The conversion efficiency is improved by using thermal cycle annealing (TCA) and a graded buffer layer. TEM micrographs show that the dislocation density is drastically decreased with using TCA. The conversion efficiency of GaAsP solar cell on Si with GaAs buffer layer is higher than that with GaP buffer layer. The improvement in the efficiency is obtained by reducing the dislocation density in the GaAsP layer.
Morphological divergence rate tests for natural selection: uncertainty of parameter estimation and robustness of results

In this study, we used a combination of geometric morphometric and evolutionary genetics methods for the inference of possible mechanisms of evolutionary divergence. A sensitivity analysis for the constant-heritability rate test results regarding variation in genetic and demographic parameters was performed, in order to assess the relative influence of uncertainty of parameter estimation on the robustness of test results. As an application, we present a study on body shape variation among populations of the poeciliine fish Poecilia vivipara inhabiting lagoons of the quaternary plains in northern Rio de Janeiro State, Brazil. The sensitivity analysis showed that, in general, the most important parameters are heritability, effective population size and number of generations since divergence. For this specific example, using a conservatively wide range of parameters, the neutral model of genetic drift could not be accepted as a sole cause for the observed magnitude of morphological divergence among populations. A mechanism of directional selection is suggested as the main cause of variation among populations in different habitats and lagoons. The implications of parameter estimation and biological assumptions and consequences are discussed.
Nutritional quality of vegetable and seed from different accessions of Amaranthus in South Africa

Amaranthus vegetable and seed are highly nutritious, but in many parts of South Africa they are hardly utilised as food. Assessment of five accessions of Amaranthus available in South Africa was carried out to select the best accession for vegetable and seed. Seeds were planted in pots in a glass house and leaves and seed were harvested. Leaves were analysed for ascorbic acid, crude protein, nitrate and minerals. Seeds were analysed for protein, fat and minerals. Ascorbic acid content in the leaves varied between 630 and 496 mg/100g. V2 contained significantly higher amount of nitrates (1 474 mg/100g) while VOP and AMA17 had the lowest (729 mg/100g). AMA 17 leaves had the highest concentrations for all the minerals that were determined in leaves. The seeds of AMA17 contained significantly higher amounts of manganese, calcium and zinc than the seeds from all other accessions and it is therefore most recommended, especially in view of the more favourable health aspects thereof. VOP seed would probably be more acceptable to the local population as food because of the cream colour compared to the black colour of the other accessions.
NuSTAR reveals the extreme properties of the super-Eddington accreting supermassive black hole in PG 1247+267

PG1247+267 is one of the most luminous known quasars at z ~ 2 and is a strongly super-Eddington accreting supermassive black hole (SMBH) candidate. We obtained NuSTAR data of this intriguing source in December 2014 with the aim of studying its high-energy emission, leveraging the broad band covered by the new NuSTAR and the archival XMM-Newton data. Several measurements are in agreement with the super-Eddington scenario for PG1247+267: the soft power law (Γ = 2.3 ± 0.1); the weak ionized Fe emission line; and a hint of the presence of outflowing ionized gas surrounding the SMBH. The presence of an extreme reflection component is instead at odds with the high accretion rate proposed for this quasar. This can be explained with three different scenarios; all of them are in good agreement with the existing data, but imply very different conclusions: i) a variable primary power law observed in a low state, superimposed on a reflection component echoing a past, higher flux state; ii) a power law continuum obscured by an ionized, Compton thick, partial covering absorber; and iii) a relativistic disk reflector in a lamp-post geometry, with low coronal height and high BH spin. The first model is able to explain the high reflection component in terms of variability. The second does not require any reflection to reproduce the hard emission, while a rather low high-energy cutoff of ~100 keV is detected for the first time in such a high redshift source. The third model require a face-on geometry, which may affect the SMBH mass and Eddington ratio measurements. Deeper X-ray broad-band data are required in order to distinguish between these possibilities.
Community structure and diet of roving herbivorous reef fishes in the Abrolhos Archipelago, south‐western Atlantic

Community structure and diet of roving herbivorous reef fishes were analysed in 13 study sites around the five islands of the Abrolhos Archipelago, north-eastern Brazil (17°58' S; 38°42' W). This area has been part of the Abrolhos Marine National Park since 1983. Abundances and diets of fishes within the families Scaridae, Acanthuridae and Kyphosidae were compared among groups of sites differing in benthic community structure and exposure regime. The abundance of roving herbivorous fishes was higher in shallower sites than in deeper sites. At all study sites, observations of total herbivorous reef fish community structure revealed that 64% of fishes were acanthurids, 33% were scarids and only 4% were kyphosids. This pattern was predominant in all study sites. The majority of fishes examined in this study had the bulk of their diet based on both algae (35-90%) and detritus (35-65%). Among groups of algae, filamentous algae were the most commonly consumed as the majority of roving herbivorous fishes in Abrolhos feed as scrapers and excavators. The exceptions were the kyphosids, which had a diet consisting primarily of macroalgae (mainly Phaeophyta), and Acanthurus coeruleus that consumed mainly turf algae and very little detritus. The data collected indicate that roving herbivorous fishes in the Abrolhos Archipelago are more abundant at calm sites where detritus and delicate algae, their major food resources, are more abundant. The results presented here, along with underwater observations, suggest that the abundance and diet of these three fish families are associated with substratum cover.
A survey of key Australian pome fruit growing districts for exotic and endemic pathogens

A survey of key Australian pome fruit growing districts for 11 quarantinable pathogens was conducted using reverse transcriptase polymerase chain reaction (RT-PCR) and PCR methods. The targeted exotic organisms included two bacteria, two phytoplasmas, four viroids and three viruses. Except for Pear blister canker viroid, which has been previously reported in Australia, no other exotic pathogen was detected. RT-PCR assays were also used to detect four endemic viruses, Apple stem pitting virus, Apple stem grooving virus, Apple chlorotic leafspot virus and Apple mosaic virus. The results showed that each virus is widespread in Australia and that many pome fruit trees are infected with a combination of two or more virus species. The results also indicated that genetic variation occurs between strains of Apple stem pitting virus and strains of Apple stem grooving virus
Computational prediction , rationalization and experimental validation of PCR primers for the detection of antibiotic resistance genes in wastewater treatment plants

Wastewater treatment plants (WWTPs) are point sources of various emerging pollutants, including antibiotics and antibiotic-resistance genes (ARGs). These reservoirs promote formation of antimicrobial resistance due to natural selection of the multidrug-resistant bacteria and horizontal gene transfer of ARGs. Therefore, there is a great need to effectively monitor the spread, diversity and fate of ARGs in WWTPs. One of the possibilities for such screening is PCR typing. However, efficient and diverse sets of primers specific to various ARGs are needed. In literature, there are plethora of such primers, however their usefulness in environmental studies varies significantly. In this study a dedicated bioinformatic in silico PCR (e-PCR) tool was created to validate and calculate various primers specificity and efficacy. Over 300 primer pairs specific to diverse ARGs families were validated against the Comprehensive Antibiotic Resistance Database (CARD) and Antibiotic Resistance Genes Database (ARDB) and various WWTPs metagenomes, which enables calculating primers overall rating and preparation of the database of PCR primers most useful in ARGs environmental screening. Finally, selected primer pairs were used in experimental PCR testing survey to check the presence of the ARGs in waste samples (collected on subsequent stages of the wastewater treatment process) from the Oswiecim WWTP (Poland).
Spatial variability in reef fish distribution, abundance, size and biomass: a multi-scale analysis

This study used underwater visual census techniques to quantify the distribution, abundance, fork lengths and biomass of scarid fishes on multiple reefs across the continental shelf of the northern Great Barrier Reef. Spatial patterns in fish distribution were examined over a cross shelf environmental gradient using a hierarchical sampling design that covered a spectrum of scales ranging from metres to tens of kilometres. The design included replicate reefs within mid and outer continental shelf positions and replicate sheltered and exposed sites within each reef. Most of the 21 species surveyed were found to be widely distributed across mid and outer shelf reefs and the number of species did not change significantly between reefs, exposures or across the shelf. Despite a similar complement of species, scarid assemblages differed markedly in the relative and absolute abundance of taxa between exposed and sheltered habitats on mid and outer shelf reefs. Principal components and cluster analyses indicated that changes in the numerical abundance of taxa resulted in consistently different assemblages from 9 sheltered mid shelf sites and 9 exposed outer shelf sites at opposite ends of the surveyed environmental gradient. Variance components calculated for scarid abundance and biomass across 4 spatial scales revealed differences in the scales at which significant variability occurred between sheltered and exposed reef habitats. On exposed reef crests significant variation occurred at both scales of tens of kilometres (shelf position) and hundreds of metres (sites), while on sheltered back reefs significant variation was attributable only to the site scale. Mean scarid abundance (±SE) for exposed outer shelf sites (3060 ± 460 ha-1) was on average 4 times higher than in all other habitat zones surveyed, while mean biomass (±SE) was only 3 times higher (920 ± 190 kg ha-1). The discrepancy between abundance and biomass estimates is explained by a 30% average decline in parrotfish fork lengths on exposed outer shelf reef crests relative to other habitats. Log-linear analysis indicated that at least 8 species of scarids displayed significant changes in body size according to their location across the continental shelf and/or the prevailing exposure regime. The observed patterns of variation in density and length frequency suggest density-dependent processes and that changes in mortality or growth rates may exist between habitats across the continental shelf.
Building a connected BLE mesh: A network inference study

Bluetooth low energy (BLE) is on the way of becoming the next standard for low-power, low-datarate applications. While not being designed directly for mesh operation, recent works have shown that both connected and broadcasts mesh are possible, this latter one being ultimately included in the standard. For any robust operation in a connected BLE mesh network, especially for high reliability and low-latency operations like healthcare, the control parameters need to be carefully chosen in order to avoid congestion and packet loss but the relationships between controllable parameters and final network performance have not yet been investigated in BLE mesh networks. In this work, we show that it is possible to infer the relationships between the controllable and observable network parameters by using a mutual information based structure learning approach; we show, in fact, how each setting such as transmit power, connection interval, source rate, impact overall network performance figures of merit such as end-to-end delay, packet delivery ratio and network build time.
Face aftereffects suggest interdependent processing of expression and sex and of expression and race

Bruce and Young (1986) proposed that functionally different aspects of faces (e.g., sex, identity, and expression) are processed independently. Although interdependent processing of identity and expression and of identity and sex have been demonstrated previously, evidence for interdependent processing of sex and expression is equivocal. Using a visual adaptation paradigm, we show that expression aftereffects can be simultaneously induced in different directions along anger–fear continua for male and female faces (Experiment 1) and for East Asian and Black African faces (Experiment 2). These findings for sex- and race-contingent expression aftereffects suggest that processing of expression is interdependent with processing of sex and race and are therefore problematic for models of face perception that have emphasized independent processing of functionally different aspects of faces. By contrast, our findings are consistent with models of face processing that propose that invariant physical aspects of faces and changeable social cues can be processed interdependently.
Clinical findings and diagnostic value of post‐traumatic thoracic radiographs in dogs and cats with blunt trauma

Objective: To characterize the clinical findings in dogs and cats that sustained blunt trauma and to compare clinical respiratory examination results with post-traumatic thoracic radiography findings. Design: Retrospective clinical study. Setting: University small animal teaching hospital. Animals, interventions and measurements: Case records of 63 dogs and 96 cats presenting with a history of blunt trauma and thoracic radiographs between September 2001 and May 2003 were examined. Clinical signs of respiratory distress (respiratory rate (RR), pulmonary auscultation) and outcome were compared with radiographic signs of blunt trauma. Results: Forty-nine percent of dogs and 63.5% of cats had radiographic signs attributed to thoracic trauma. Twenty-two percent of dogs and 28% of cats had normal radiographs. Abnormal auscultation results were significantly associated with radiographic signs of thoracic trauma, radiography score and presence and degree of contusions. Seventy-two percent of animals with no other injuries showed signs of thoracic trauma on chest radiographs. No correlation was found between the radiographic findings and outcome, whereas the trauma score at presentation was significantly associated with outcome and with signs of chest trauma but not with the radiography score. Conclusion: Thoracic trauma is encountered in many blunt trauma patients. The RR of animals with blunt trauma is not useful in predicting thoracic injury, whereas abnormal chest auscultation results are indicative of chest abnormalities. Thorough chest auscultation is, therefore, mandatory in all trauma animals and might help in the assessment of necessity of chest radiographs.
Helminth community structure and diet of three Afrotropical anuran species: a test of the interactive-versus-isolationist parasite communities hypothesis

Abstract. The interactive-versus-isolationist hypothesis predicts that parasite communities should be depauperated and weakly structured by interspecific competition in amphibians. A parasitological survey was carried out to test this hypothesis using three anuran species from Nigeria, tropical Africa (one Bufonidae; two Ranidae). High values of parasite infection parameters were found in all three species, which were infected by nematodes, cestodes and trematodes. Nonetheless, the parasite communities of the three anurans were very depauperated in terms of number of species (4 to 6). Interspecific competition was irrelevant in all species, as revealed by null models and Monte Carlo permutations. Cluster analyses revealed that, in terms of parasite community composition, the two Ranidae were similar, whereas the Bufonidae was more different. However, when prevalence, intensity, and abundance of parasites are combined into a multivariate analysis, each anuran species was clearly spaced apart from the others, thus revealing considerable species-specific differences in terms of their parasite communities. All anurans were generalists and probably opportunistic in terms of dietary habits, and showed no evidence of interspecific competition for food. Overall, our data are widely consistent with expectations driven from the interactive-versus-isolationist parasite communities hypothesis.
Role of Helicobacter Pylori Infection in the Pathogenesis of Minimal Hepatic Encephalopathy and Effect of its Eradication

Background and purpose Minimal hepatic encephalopathy (MHE) is the mildest form in the spectrum of hepatic encephalopathy (HE); it has no recognizable clinical symptoms but mild cognitive and psychomotor deficits. Neuropsychometric testing is an established methodology for quantifying cognitive impairment in MHE. Ammonia is important in the pathogenesis of MHE and H. pylori are known to produce copious amounts of ammonia, thus, it may contribute to the development of MHE in the presence of liver cirrhosis. The study aimed to detect the prevalence of H. pylori infection in cirrhotic patients with and without MHE and to establish the correlation between the presence of H. pylori infection and blood ammonia level and the results of neuropsychometric tests in these cases. Moreover, to investigate the effect of H. pylori eradication on different measured parameters. Material and Methods 80 patients with HCV related liver cirrhosis were included in the study; patients were divided according to the presence or absence of MHE and H. pylori infection into 4 subgroups. Full history taking, routine laboratory investigations, fasting blood ammonia level and detection of H. pylori antigen in stool were done to all studied patients. Also, neuropsychometric tests were performed for diagnosis of MHE. Results and conclusion H. pylori infection is common among cirrhotic Egyptian patients and its role in the pathogenesis of MHE and ammonia production was proved. Screening of cirrhotic patients for detection and eradication of H. pylori is beneficial in the improvement and cure of MHE for better quality of life.