189 research outputs found

    Процессы низкотемпературной дипольной релаксации в системах бычий сывороточный альбумин–нанооксид–вода

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    Методом термостимулированной деполяризации проведены сравнительные исследования процессов низкотемпературной дипольной релаксации в замороженных водных дисперсиях нанооксидов, индивидуальных и в присутствии бычьего сывороточного альбумина (БСА). Для последних систем характерно увеличение вкладов релаксационных процессов при Т > 160–170 К, в то время как для водных дисперсий оксидов бóльшие токи ТСД наблюдаются при Т 160…170 К, в той час як для водних дисперсій оксидів більші струми ТСД спостерігаються при Т 160- 170 К, since for aqueous suspensions of nanooxides, greater TSD currents are observed at Т < 160-170 К. This difference is due to the participation of the BSA molecules (polar bonds, groups, fragments, whole molecules) in the relaxation processes, whose features depend also on the nature of nanooxide and a character of BSA interactions with its surface

    Comparing Languages for Engineering Server Software: Erlang, Go, and Scala with Akka

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    Servers are a key element of current IT infrastructures, and must often deal with large numbers of concurrent requests. The programming language used to construct the server has an important role in engineering efficient server software, and must support massive concurrency on multicore machines with low communication and synchronisation overheads. This paper investigates 12 highly concurrent programming languages suitable for engineering servers, and analyses three representative languages in detail: Erlang, Go, and Scala with Akka. We have designed three server benchmarks that analyse key performance characteristics of the languages. The benchmark results suggest that where minimising message latency is crucial, Go and Erlang are best; that Scala with Akka is capable of supporting the largest number of dormant processes; that for servers that frequently spawn processes Erlang and Go minimise creation time; and that for constantly communicating processes Go provides the best throughput

    Definition of Estrogen Receptor Pathway Critical for Estrogen Positive Feedback to Gonadotropin-Releasing Hormone Neurons and Fertility

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    SummaryThe mechanisms through which estrogen regulates gonadotropin-releasing hormone (GnRH) neurons to control mammalian ovulation are unknown. We found that estrogen positive feedback to generate the preovulatory gonadotropin surge was normal in estrogen receptor β knockout (ERβ) mutant mice, but absent in ERα mutant mice. An ERα-selective compound was sufficient to generate positive feedback in wild-type mice. As GnRH neurons do not express ERα, estrogen positive feedback upon GnRH neurons must be indirect in nature. To establish the cell type responsible, we generated a neuron-specific ERα mutant mouse line. These mice failed to exhibit estrogen positive feedback, demonstrating that neurons expressing ERα are critical. We then used a GnRH neuron-specific Pseudorabies virus (PRV) tracing approach to show that the ERα-expressing neurons innervating GnRH neurons are located within rostral periventricular regions of the hypothalamus. These studies demonstrate that ovulation is driven by estrogen actions upon ERα-expressing neuronal afferents to GnRH neurons

    Inhibition of platelet-derived growth factor signaling attenuates pulmonary fibrosis

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    Pulmonary fibrosis is the consequence of a variety of diseases with no satisfying treatment option. Therapy-induced fibrosis also limits the efficacy of chemotherapy and radiotherapy in numerous cancers. Here, we studied the potential of platelet-derived growth factor (PDGF) receptor tyrosine kinase inhibitors (RTKIs) to attenuate radiation-induced pulmonary fibrosis. Thoraces of C57BL/6 mice were irradiated (20 Gy), and mice were treated with three distinct PDGF RTKIs (SU9518, SU11657, or Imatinib). Irradiation was found to induce severe lung fibrosis resulting in dramatically reduced mouse survival. Treatment with PDGF RTKIs markedly attenuated the development of pulmonary fibrosis in excellent correlation with clinical, histological, and computed tomography results. Importantly, RTKIs also prolonged the life span of irradiated mice. We found that radiation up-regulated expression of PDGF (A–D) isoforms leading to phosphorylation of PDGF receptor, which was strongly inhibited by RTKIs. Our findings suggest a pivotal role of PDGF signaling in the pathogenesis of pulmonary fibrosis and indicate that inhibition of fibrogenesis, rather than inflammation, is critical to antifibrotic treatment. This study points the way to a potential new approach for treating idiopathic or therapy-related forms of lung fibrosis

    Observational Study Design in Veterinary Pathology, Part 1: Study Design

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    Observational studies are the basis for much of our knowledge of veterinary pathology and are highly relevant to the daily practice of pathology. However, recommendations for conducting pathology-based observational studies are not readily available. In part 1 of this series, we offer advice on planning and conducting an observational study with examples from the veterinary pathology literature. Investigators should recognize the importance of creativity, insight, and innovation in devising studies that solve problems and fill important gaps in knowledge. Studies should focus on specific and testable hypotheses, questions, or objectives. The methodology is developed to support these goals. We consider the merits and limitations of different types of analytic and descriptive studies, as well as of prospective vs retrospective enrollment. Investigators should define clear inclusion and exclusion criteria and select adequate numbers of study subjects, including careful selection of the most appropriate controls. Studies of causality must consider the temporal relationships between variables and the advantages of measuring incident cases rather than prevalent cases. Investigators must consider unique aspects of studies based on archived laboratory case material and take particular care to consider and mitigate the potential for selection bias and information bias. We close by discussing approaches to adding value and impact to observational studies. Part 2 of the series focuses on methodology and validation of methods

    Принципи управління персоналом сільськогосподарських підприємств (на прикладі Луганської області)

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    У статті проаналізовано сучасний стан сільськогосподарського виробництва в Луганській області та здійснена оцінка перспектив реформування управління персоналом на підприємствах АПК. Регресійним аналізом оцінено ступінь впливу деяких факторів на рентабельність персоналу. Рекомендується використання SWOT-аналізу для дослідження й формування раціонального управління персоналом підприємств АПК.Performed analysis of the current state of agriculture in the Luhansk region, evaluated the prospects for personnel resources reforming for the agricultural enterprises. The degree of factors influencing on profitability of personnel is appraised by the regressive analysis. SWOT-analysis is recommended for research and forming of agrarian enterprises rational management of a personnel

    Insights into the regulation of DMSP synthesis in the diatom Thalassiosira pseudonana through APR activity, proteomics and gene expression analyses on cells acclimating to changes in salinity, light and nitrogen

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    Despite the importance of dimethylsulphoniopropionate (DMSP) in the global sulphur cycle and climate regulation, the biological pathways underpinning its synthesis in marine phytoplankton remain poorly understood. The intracellular concentration of DMSP increases with increased salinity, increased light intensity and nitrogen starvation in the diatom Thalassiosira pseudonana. We used these conditions to investigate DMSP synthesis at the cellular level via analysis of enzyme activity, gene expression and proteome comparison. The activity of the key sulphur assimilatory enzyme, adenosine 5′- phosphosulphate reductase was not coordinated with increasing intracellular DMSP concentration. Under all three treatments coordination in the expression of sulphur assimilation genes was limited to increases in sulphite reductase transcripts. Similarly, proteomic 2D gel analysis only revealed an increase in phosphoenolpyruvate carboxylase following increases in DMSP concentration. Our findings suggest that increased sulphur assimilation might not be required for increased DMSP synthesis, instead the availability of carbon and nitrogen substrates may be important in the regulation of this pathway. This contrasts with the regulation of sulphur metabolism in higher plants, which generally involves upregulation of several sulphur assimilatory enzymes. In T. pseudonana changes relating to sulphur metabolism were specific to the individual treatments and, given that little coordination was seen in transcript and protein responses across the three growth conditions, different patterns of regulation might be responsible for the increase in DMSP concentration seen under each treatment

    Parasites in the inner ear of harbour porpoise: Cases from the North and baltic seas

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    Peribullar sinuses of harbour porpoises Phocoena phocoena are parasitized with high prevalence by the nematode Stenurus minor. The effect of S. minor on the hearing ability of this species is still undetermined. Here, we review the occurrence of S. minor in the inner ear of harbour porpoises recovered from strandings in the North and Baltic Seas. In particular, we present the results from ears collected in German and Danish waters from 2002 to 2016 and from Dutch waters from 2010 to 2016. While the prevalence of S. minor in pterygoid and peribullar sinuses and tympanic cavity was high in harbour porpoises (66.67% in our cases), its prevalence in the cochlea was rare. Only 1 case out of 129 analysed by either histology, electron microscopy or immunofluorescence showed the presence of a nematode parasite morphologically consistent with S. minor at the most basal portion of the right cochlea. This individual also had severe haemorrhage along the right cochlear spiral, which was likely caused by ectopic S. minor migration. Although this animal might have had impaired hearing in the right ear, it was otherwise in good body condition with evidence of recent feeding. These findings highlight the need to study the effect of parasites on hearing, and other pathological changes that might impair appropriate processing of acoustic information.Postprint (author's final draft
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