Overlapping community detection using core label propagation algorithm and belonging functions

Applied Intelligence - The community detection in complex networks has become a major field of research. Disjoint community detection deals often with getting a partition of nodes where every node...     

Partial Sperm beta1 Integrin Subunit Deletion Proves Its Involvement in Mouse Gamete Adhesion/Fusion

We have previously shown, using antibodies, that the sperm alpha6beta1 integrin is involved in mouse gamete fusion in vitro. Here we report the conditional knockdown of the sperm Itgb1 gene. It induced a drastic failure of sperm fusogenic ability with sperm accumulation in the perivitelline space of in vitro inseminated oocytes deleted or not for the Itgb1 gene. These data demonstrate that sperm, but not oocyte, beta1 integrin subunit is involved in gamete adhesion/fusion. Curiously, knockdown males were fertile in vivo probably because of the incomplete Cre-mediated deletion of the sperm Itgb1 floxed gene. Indeed, this was shown by Western blot analysis and confirmed by both the viability and litter size of pups obtained by mating partially sperm Itgb1 deleted males with females producing completely deleted Itgb1 oocytes. Because of the total peri-implantation lethality of Itgb1 deletion in mice, we assume that sperm that escaped the Itgb1 excision seemed to be preferentially used to fertilize in vivo. Here, we showed for the first time that the deletion, even partial, of the sperm Itgb1 gene makes the sperm unable to normally fertilize oocytes. However, to elucidate the question of the essentiality of its role during fertilization, further investigations using a mouse expressing a recombinase more effective in male germ cells are necessary.     

Can energy optimization lead to economic and environmental waste in LPWAN architectures?

As low-power wide-area network (LPWAN) end devices (EDs) are deployed in massive scale, their economic and environmental costs of operation are becoming too significant to ignore and too difficult to estimate. While LPWAN architectures and protocols are designed to primarily save energy, this study shows that energy saving does not necessarily lead to lower cost or environmental footprint of the network. Accordingly, a theoretical framework is proposed to estimate the operational expenditure (OpEx) and environmental footprint of LPWAN EDs. An extended constrained optimization model is provided for the ED link assignment to gateways (GWs) based on heterogeneous ED configurations and hardware specifications. Based on the models, a simulation framework is developed which demonstrates that OpEx, energy consumption, and environmental footprint can be in conflict with each other as constrained optimization objectives. We demonstrate different ways to achieve compromises in each dimension for overall improved network performance.     

Local measurements of fluid and particle velocities in a stirred suspension

An experimental approach is proposed for the measurement of the local behaviour of continuous and dispersed phases in a stirred suspension at low particle concentrations (0.5 vol.%). The basic principle involves the simultaneous measurement of the local velocity and particle size with a phase Doppler velocimeter and the separation of the data obtained from large particles (representing the dispersed phase) and very small particles (representing the motion of the continuous liquid phase).This technique was applied to the investigation of a fully baffled cylindrical vessel, with a flat bottom, stirred by an industrial axial propeller. The diameters of the vessel and the propeller and the vertical clearance were 0.3 m, 0.14 m and 0. l m respectively. The liquid was water and spherical glass particles were used as the dispersed phase.In the absence of particles, the circulation pattern created by the propeller in the middle plane between two baffles revealed a major circulation loop in the lower part of the vessel and a minor contra-rotative loop in the wall surface corner. The calculated pumping coefficient, circulation flow number, non-dimensional time of renewal and circulation time were 0.62, 0.89, 11.76 and 8.15 respectively. The tangential velocities remained at values of less than 15% of the impeller tip velocity in the plane of the measurements.Axial, radial and tangential mean and root-mean-square velocities for the carrier liquid phase and particles were measured in the two-phase flow, using particles with a mean diameter of 253 μm. These measurements showed that the particles lagged behind the liquid phase in the upward parts of the flow field, but were ahead in some downward parts. The root-mean-square axial velocities obtained for the particles were always greater than these obtained for the continuous phase. Non-homogeneities in the suspension were observed by the local mean diameter field. The effects of the stirring rate and size of the particles were also checked in the upward part of the flow in the vessel.     

Minimizing the Consequences of Intentional Attack on Water Infrastructure

Abstract:  Since September 11, 2001, protecting the nation's water infrastructure and improving water network resiliency have become priorities in the water industry. In this work, we develop methods to mitigate the consequences of water shortage resulting from destruction of facilities in water networks. These methods integrate search techniques, such as branch-and-bound and genetic algorithms, with a hydraulic solver to check demand feasibilities across a residual water network. The objective is to identify a feasible customer demand pattern that minimizes the consequences of water shortage in the downgraded network. We present a mathematical model of the problem addressed along with an exact solution methodology and several heuristics. We apply these methodologies to three water networks ranging in size from approximately 10–700 nodes and compare the solution quality and computational efficiency.     

Nanotube transistors as direct probes of the trap dynamics at dielectric-organic interfaces of interest in organic electronics and solar cells

The high sensitivity of nanotube transistors is used for the first time as a probe to study charge dynamics at a dielectric/polymer (polythiophene) interface, an inorganic/organic junction of particular importance for organic solar cells, and organic field effect transistors (OFETs). A carbon nanotube field effect transistor is coated with a thin film of a photoconductive polymer and photoexcited so as to generate carriers in the structure. Comparison between devices using SiO2 and TiO2 as gate dielectric reveals the critical role of the dielectric and clearly elucidates the relative contributions of the polymer and the dielectric layers on the separation, trapping, and relaxation of photogenerated charges.     

Unsaturated zone arsenic distribution and implications for groundwater contamination

Arsenic compounds have been applied at the land surface as pesticides in agricultural areas globally. The purpose of this study was to evaluate the fate of anthropogenic arsenic applications related to agriculture, using arsenic applications on cotton in the southern High Plains (SHP), Texas, as a case study and examining possible linkages with contamination of the underlying Ogallala aquifer in this region, where 36% of wells exceed the new EPA 10 microg/L standard. Unsaturated zone soil samples were collected from boreholes beneath natural ecosystems (grassland/ shrubland) to provide a control (no arsenic application) (5 profiles) and cotton cropland (20 profiles) for analyses of water-extractable arsenic, vanadium, phosphate, chloride, and nitrate. Natural ecosystem profiles have high arsenic concentrations at depth (maximum of 7.2-69.6 microg As/ kg dry soil at 5.9-21.4 m depth) that are attributed to a geologic source. Most profiles beneath cotton cropland have high arsenic concentrations within the upper meter (profile means 1.7 to 31.6 microg/kg) that correlate with phosphate (r = 0.70, p < 0.01) and are attributed to anthropogenic arsenic application associated with phosphate fertilizer application. High arsenic concentrations at >1 m depth (profile means < or =36.3 microg/kg) found in cropland profiles are attributed to a geologic source because of similarity with profiles beneath natural ecosystems, lack of correlation with phosphate, and pore-water ages that predate anthropogenic arsenic application in many profiles. GIS analyses showed poor correlations between groundwater arsenic and percent cultivated land (r = -0.15, p < 0.01), groundwater nitrate (r = 0.30, p < 0.01), and water table depth (r= -0.31, p < 0.01), further supporting the idea that anthropogenic-derived arsenic in the shallow subsurface is not linked to groundwater arsenic contamination in this region.     

Coupling dark fermentation and microbial electrolysis to enhance bio-hydrogen production from agro-industrial wastewaters and by-products in a bio-refinery framework

The aim of this work is to evaluate biohydrogen production from agro-industrial wastewaters and by-products, by combining dark fermentation and microbial electrolysis in a two-step cascade process. Such coupling of both technologies constitutes a technological building block within a concept of environmental biorefinery where sustainable production of renewable energy is expected.Six different wastewaters and industrial by-products coming from cheese, fruit juice, paper, sugar, fruit processing and spirits factories were evaluated for the feasibility of hydrogen production in a two-step process. The overall hydrogen production when coupling dark fermentation and microbial electrolysis was increased up to 13 times when compared to fermentation alone, achieving a maximum overall hydrogen yield of 1608.6 ± 266.2 mLH₂/gCOD_consumed and a maximum of 78.5 ± 5.7% of COD removal.These results show that dark fermentation coupled with microbial electrolysis is a highly promising option to maximize the conversion of agro-industrial wastewaters and by-products into bio-hydrogen.     

On the Room-Temperature Mechanical Properties of an Ion-Irradiated TiZrNbHfTa Refractory High Entropy Alloy

JOM - Refractory high-entropy alloys (RHEAs) are potential candidate materials for use in next-generation nuclear reactors due to their excellent mechanical performance at high temperatures. Here,...     

Bleeding and Thrombosis: Insights into Pathophysiology of Bothrops Venom-Related Hemostasis Disorders

Toxins from Bothrops venoms targeting hemostasis are responsible for a broad range of clinical and biological syndromes including local and systemic bleeding, incoagulability, thrombotic microangiopathy and macrothrombosis. Beyond hemostais disorders, toxins are also involved in the pathogenesis of edema and in most complications such as hypovolemia, cardiovascular collapse, acute kidney injury, myonecrosis, compartmental syndrome and superinfection. These toxins can be classified as enzymatic proteins (snake venom metalloproteinases, snake venom serine proteases, phospholipases A₂ and L-amino acid oxidases) and non-enzymatic proteins (desintegrins and C-type lectin proteins). Bleeding is due to a multifocal toxicity targeting vessels, platelets and coagulation factors. Vessel damage due to the degradation of basement membrane and the subsequent disruption of endothelial cell integrity under hydrostatic pressure and tangential shear stress is primarily responsible for bleeding. Hemorrhage is promoted by thrombocytopenia, platelet hypoaggregation, consumption coagulopathy and fibrin(ogen)olysis. Onset of thrombotic microangiopathy is probably due to the switch of endothelium to a prothrombotic phenotype with overexpression of tissue factor and other pro-aggregating biomarkers in association with activation of platelets and coagulation. Thrombosis involving large-caliber vessels in B. lanceolatus envenomation remains a unique entity, which exact pathophysiology remains poorly understood.