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Water resources have fundamental importance both for living beings life and for human activities. The lack of water can be a limiting factor for occupation and development of a certain region. Photovoltaic pumping systems are an alternative solution for remote locations, with electric generation from photovoltaic panels being a locally pollutant-free option and less maintenance when compared to combustion-generation engines. This work aims the analysis of a photovoltaic pumping system with two cell technologies, amorphous and polycrystalline silicon. The research shown an average volume pumped of 2,255.44 and 2,397.01 litres per day in the amorphous and polycrystalline systems, respectively. The best efficiency results in both systems were at 0.8 kWhm−2, 4.69% for amorphous and 7.75% polycrystalline. However, the first one presented lower voltage drop with panel's temperature increasing. It obtained higher flow and overall efficiency in the polycrystalline system. [ABSTRACT FROM AUTHOR]

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The article presents a study which examined the use of albumin and cholesterol dosages and serum aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT) activities in detecting hepatic histopathological injuries. The researchers performed the study on 220 healthy Nelore male cattle from several farms in Brazil's Goias state. Detection of minor liver injuries was found to be limited but high specificity of the GGT allows it to be used as an indicator of hepatic chronic injuries.

We study the performance of a quantum Otto heat engine with two spins coupled by a Heisenberg interaction, taking into account not only the mean values of work and efficiency but also their fluctuations. We first show that, for this system, the output work and its fluctuations are directly related to the magnetization and magnetic susceptibility of the system at equilibrium with either heat bath. We analyze the regions where the work extraction can be done with low relative fluctuation for a given range of temperatures, while still achieving an efficiency higher than that of a single spin system heat engine. In particular, we find that, due to the presence of "idle" levels, an increase in the interspin coupling can either increase or decrease fluctuations, depending on the other parameters. In all cases, however, we find that the relative fluctuations in work or efficiency remain large, implying that this microscopic engine is not very reliable as a source of work.

The optical response of layered transition metal dichalcogenides (TMDCs) exhibits remarkable excitonic properties which are important from both fundamental and device application viewpoints. One of these phenomena is the observation of intralayer/interlayer excitons. While much effort has been done to characterize excitons in monolayer TMDCs and their heterostructures, a quite limited number of works have addressed the exciton spectra of their bulk counterparts. In this work, we employ ab initio many-body perturbation calculations to investigate the exciton dynamics and spectra of bulk 2H-MX 2 (M = Mo, W, and X = S, Se). For molybdenum-based systems, we find the presence of interlayer excitons at energies higher than the first bright exciton (X A ), with non-negligible strength intensity. Our results also show that interlayer excitons in tungsten-based systems are almost degenerate in energy with X A and possess very small oscillator strengths when compared with molybdenum-based systems. At room temperature, and considering the thermal exciton fine-structure population for the X A -exciton, we estimate effective radiative lifetimes in the range of ∼4-14 ns. For higher energy excitons we predict longer effective lifetimes of tens of nanoseconds.

This study aims to investigate the glacier shrinkage and recent proglacial environment in King George Bay, Antarctica, since 1988 in response to climate change. Remote sensing data (SPOT, Sentinel, Landsat and Planet Scope images) were applied to glacial landforms and ice-marginal fluctuations mapping. Annual mean near-surface air temperature reanalysis solutions from ERA-Interim were analyzed. Moraines and glaciofluvial landforms were identified. The Ana Northern Glacier has the highest retreat value (3.64 km) (and area loss of 31%) in response to higher depth in frontal ice-margin and reveal ocean-glacier linkages. The Ana South Glacier changed from a tidewater glacier to land-terminating after 1995, and had an outline minimum elevation variation of 89 meters, a shrinkage of 0.63 km, and a new proglacial subaerial sector. The Ana South Glacier foreland had recessional moraines (probably formed between 1995 and 2022), lagoons, and lakes. There are many flutings in low-relief environments. The 1980-1989, 1990-1999, 2000-2009, 2010-2019 anomaly plots concerning to the 1980-2019 average for atmospheric temperature, are shown to be a driver of the local glacial trends.