1,048 research outputs found

    The role of renal transporters and novel regulatory interactions in the TAL that control blood pressure

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    Hypertension (HTN), a major public health issue is currently the leading factor in the global burden of disease, where associated complications account for 9.4 million deaths worldwide every year (98). Excessive dietary salt intake is among the environmental factors that contribute to HTN, known as salt sensitivity. The heterogeneity of salt sensitivity and the multiple mechanisms that link high salt intake to increases in blood pressure are of upmost importance for therapeutic application. A continual increase in the kidney's reabsorption of sodium (Na+) relies on sequential actions at various segments along the nephron. When the distal segments of the nephron fail to regulate Na+, the effects on Na+ homeostasis are unfavourable. We propose that the specific nephron region where increased active uptake occurs as a result of variations in Na+ reabsorption is at the thick ascending limb of the loop of Henle (TAL). The purpose of this review is to urge the consideration of the TAL that contributes to the pathophysiology of salt sensitive HTN. Further research in this area will enable development of a therapeutic application for targeted treatment

    Spontaneous emission of an atom near an oscillating mirror

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    We investigate the spontaneous emission of one atom placed near an oscillating reflecting plate. We consider the atom modeled as a two-level system, interacting with the quantum electromagnetic field in the vacuum state, in the presence of the oscillating mirror. We suppose that the plate oscillates adiabatically, so that the time-dependence of the interaction Hamiltonian is entirely enclosed in the time-dependent mode functions, satisfying the boundary conditions at the plate surface, at any given time. Using time-dependent perturbation theory, we evaluate the transition rate to the ground-state of the atom, and show that it depends on the time-dependent atom-plate distance. We also show that the presence of the oscillating mirror significantly affects the physical features of the spontaneous emission of the atom, in particular the spectrum of the emitted radiation. Specifically, we find the appearance of two symmetric lateral peaks in the spectrum, not present in the case of a static mirror, due to the modulated environment. The two lateral peaks are separated from the central peak by the modulation frequency, and we discuss the possibility to observe them with actual experimental techniques of dynamical mirrors and atomic trapping. Our results indicate that a dynamical (i.e., time-modulated) environment can give new possibilities to control and manipulate also other radiative processes of two or more atoms or molecules nearby, for example their cooperative decay or the resonant energy transfer

    Particulate Characterization and Control Evaluation for Carbon Fiber Composite Aircraft Crash Recovery Operations

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    Within the United States Air Force (USAF) Advanced Composite Material (ACM) is gaining an increasing use in military aircraft. With the number of aircraft that have increasingly large amounts of ACM materials, the probability of an incident with one of these aircraft also increases. When such an incident occurs the aircraft needs to be disassembled, removed, and later inspected as part of the accident investigation process. This disassembly process is termed “Crash Recovery Operations.” Carbon fibers have been shown to be hazardous to human health and a pilot study raised the suspicion that nanosized aerosol may be generated during the cutting of carbon fiber panels. Due to this, a bench top study was conducted to evaluate the effectiveness of several fiber controls. Additionally, an evaluation of a number of direct reading instruments and traditional gravimetric sampling techniques were evaluated to determine a sampling protocol for evaluation composite fibers. A statistically significant (F-value = \u3c 0.0001) shift towards larger diameters in the idealized particle size distribution was shown for both wetted water and water controls when compared to a baseline of no control when cutting burnt ACM. Recommendations for future evaluation and control of composite fiber processes were made

    Autoimmune Disorders and Lymphomas

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    Random wave run-up with a physically-based Lagrangian shoreline model

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    n the present paper the run-up of random waves was calculated by means of a numerical method. In situ measurements based on a video imaging technique have been used for the validation of the present numerical model. The on-site run-up measurements have been carried out at Lido Signorino beach, near Marsala, Italy,along a transect, normal to the shore. A video camera and a linear array of rods have been used to obtain field data. Numerical simulations with a 1DH Boussinesq-type of model for breaking waves which takes into account the wave run-up by means of a Lagrangian shoreline model have been carried out. In such simulations random waves of given spectrum have been propagated in a numerical flume having the same beach slope of the measured transect. The comparison between registered and estimated run-up underlined an acceptable agreement. Indeed, the numerical model tends to underestimate the actual R2%, with the maximum underestimate being less than 24%, which is a reasonable error in many cases of engineering interest

    Spatial entanglement and state engineering via four-photon Hong-Ou-Mandel interference

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    The phenomenon of entanglement is the basis of quantum information and quantum communication processes. Entangled systems with a large number of photons are of great interest at present because they provide a platform for streaming technologies based on photonics. In this paper we present a device which operates with four-photons and based on the Hong-Ou-Mandel (HOM) interference. The presented device allows to maximize the degree of spatial entanglement and generate the highly entangled four-dimensional Bell states. Furthermore, the use of the interferometer in different regimes leads to fast interference fringes in the coincidence probability with period of oscillations twice smaller than the pump wavelength. We have a good agreement between theoretical simulations and experimental results.Comment: 20 pages, 7 figur

    A new fungal isolates applicated to bovine skin in beamhouse processes

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    Content: Beamhouse area is an important step in leather technology, either in the final quality of the leather or in the contribution to the contamination of effluents. In unhairing process, the use of enzymes as sulphide assistants can reduce sulfhidric gas emissions to reach permitted levels for health. The characterization of enzymatic extracts allows controlling the proteolysis mechanism so that its action does not attack the reticular structure. A new fungal enzyme extracts were applied on submerged bovine skin in the soaking and unhairing steps. Fungal strains were isolated from alkaline soils of coast of Buenos Aires province and enzymatic extracts (EE) were obtained by submerged culture with bovine hair waste from hair-saving unhairing process as inducer in the production of keratinolytic enzymes. This activity was determined by quantitative test and the most productive strains were selected: Clonostachys rosea (CR), Emericellopsis minima (EM), Paecilomyces lilacinus (PL), Penicillium sp (Psp), Fusarium oxysporum (FO), Acremonium sp (A) and an unidentified filamentous fungus strain with sterile yellow mycelium (SYM). EE were tested at laboratory scale on submerged bovine skin with biocide 0,2% w/w wet skin, anionic 0,1% and non-ionic 0,5% tensioactives in soaking and unhairing respectively and incubated 48 h at 37°C in shaking thermostatic bath. Controls were tested in the same conditions without EE. Morphological changes in the skin were observed by scanning electron microscopy (SEM). Pieces of bovine skin were fixed, post-fixed in formaldehyde 4% and dehydrated in alcohol solutions, treated by critical point drying, metalized and analyzed in SEM. It was observed with FO, EM and A extracts empty hair follicles, absence of epidermis, papillary layer of dermis exposed, hairs enclosed by detached hair follicle sheaths and collagen fibers without characteristic patterns. With PL and SYM EE some hairs were detached while Psp and CR EE did not produce changes. In control samples epidermis and hair without modification were observed. In the quantitative test, keratinolytic activities increased in the following order: A<PL<Psp<CR<FO<SYM. Submerged culture with keratin as inductor produced keratinolytic enzymes useful for unhairing step. Fusarium oxysporum extract showed the greatest effect on the skin, thus the relationship between keratinolytic activity and depilatory effect was found. However, it is necessary to find the optimal conditions to avoid the damage of collagen and enable its application as a sustainable technology. Take-Away: A new fungal isolates applicated to bovine skin in beamhouse processe

    Aerobic growth of Rhodococcus aetherivorans BCP1 using selected naphthenic acids as the sole carbon and energy sources

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    Naphthenic acids (NAs) are an important group of toxic organic compounds naturally occurring in hydrocarbon deposits. This work shows that Rhodococcus aetherivorans BCP1 cells not only utilize a mixture of eight different NAs (8XNAs) for growth but they are also capable of marked degradation of two model NAs, cyclohexanecarboxylic acid (CHCA) and cyclopentanecarboxylic acid (CPCA) when supplied at concentrations from 50 to 500 mgL-1. The growth curves of BCP1 on 8XNAs, CHCA, and CPCA showed an initial lag phase not present in growth on glucose, which presumably was related to the toxic effects of NAs on the cell membrane permeability. BCP1 cell adaptation responses that allowed survival on NAs included changes in cell morphology, production of intracellular bodies and changes in fatty acid composition. Transmission electron microscopy (TEM) analysis of BCP1 cells grown on CHCA or CPCA showed a slight reduction in the cell size, the production of EPS-like material and intracellular electron-transparent and electron-dense inclusion bodies. The electron-transparent inclusions increased in the amount and size in NA-grown BCP1 cells under nitrogen limiting conditions and contained storage lipids as suggested by cell staining with the lipophilic Nile Blue A dye. Lipidomic analyses revealed significant changes with increases of methyl-branched (MBFA) and polyunsaturated fatty acids (PUFA) examining the fatty acid composition of NAs-growing BCP1 cells. PUFA biosynthesis is not usual in bacteria and, together with MBFA, can influence structural and functional processes with resulting effects on cell vitality. Finally, through the use of RT (Reverse Transcription)-qPCR, a gene cluster (chcpca) was found to be transcriptionally induced during the growth on CHCA and CPCA. Based on the expression and bioinformatics results, the predicted products of the chcpca gene cluster are proposed to be involved in aerobic NA degradation in R. aetherivorans BCP1. This study provides first insights into the genetic and metabolic mechanisms allowing a Rhodococcus strain to aerobically degrade NAs
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