525 research outputs found
Octopamine underlies the counter-regulatory response to a glucose deficit in honeybees (Apis mellifera)
An animal’s internal state is a critical parameter required for adaptation to
a given environment. An important aspect of an animal’s internal state is the
energy state that is adjusted to the needs of an animal by energy homeostasis.
Glucose is one essential source of energy, especially for the brain. A
shortage of glucose therefore triggers a complex response to restore the
animal’s glucose supply. This counter-regulatory response to a glucose deficit
includes metabolic responses like the mobilization of glucose from internal
glucose stores and behavioral responses like increased foraging and a rapid
intake of food. In mammals, the catecholamines adrenalin and noradrenalin take
part in mediating these counter-regulatory responses to a glucose deficit. One
candidate molecule that might play a role in these processes in insects is
octopamine (OA). It is an invertebrate biogenic amine and has been suggested
to derive from an ancestral pathway shared with adrenalin and noradrenalin.
Thus, it could be hypothesized that OA plays a role in the insect’s counter-
regulatory response to a glucose deficit. Here we tested this hypothesis in
the honeybee (Apis mellifera), an insect that, as an adult, mainly feeds on
carbohydrates and uses these as its main source of energy. We investigated
alterations of the hemolymph glucose concentration, survival, and feeding
behavior after starvation and examined the impact of OA on these processes in
pharmacological experiments. We demonstrate an involvement of OA in these
three processes in honeybees and conclude there is an involvement of OA in
regulating a bee’s metabolic, physiological, and behavioral response following
a phase of prolonged glucose deficit. Thus, OA in honeybees acts similarly to
adrenalin and noradrenalin in mammals in regulating an animal’s counter-
regulatory response
Inhibition of Glycolysis Reduces Disease Severity in an Autoimmune Model of Rheumatoid Arthritis.
The K/BxN mouse is a spontaneous model of arthritis driven by T cell receptor transgenic CD4+ T cells from the KRN strain that are activated by glucose-6-phosphate isomerase (GPI) peptides presented by the H-2g7 allele from the NOD strain. It is a model of autoimmune seropositive arthritis because the production of anti-GPI IgG is necessary and sufficient for joint pathology. The production of high levels of anti-GPI IgG requires on the expansion of CD4+ follicular helper T (Tfh) cells. The metabolic requirements of this expansion have never been characterized. Based on the therapeutic effects of the combination of metformin and 2-deoxyglucose (2DG) in lupus models that normalized the expansion of effector CD4+ T cells. We showed that the CD4+ T cells and to a lesser extent, the B cells from K/BxN mice are more metabolically active than the KRN controls. Accordingly, preventive inhibition of glycolysis with 2DG significantly reduced joint inflammation and the activation of both adaptive and innate immune cells, as well as the production of pathogenic autoantibodies. However, contrary to the lupus-prone mice, the addition of metformin had little beneficial effect, suggesting that glycolysis is the major driver of immune activation in this model. We propose that K/BxN mice are another model in which autoreactive Tfh cells are highly glycolytic and that their function can be limited by inhibiting glucose metabolism
Анализ параметров работы установки для обогащения лития по литию - 7 амальгамно - обменным способом
Работа посвящена анализу эффективности протекания процесса обогащения лития по тяжелому изотопу литий-7 в колоннах в зависимости от внешних потоков, температуры и других параметров.The work is devoted to the analysis of the efficiency of the process of lithium enrichment in the heavy lithium-7 isotope in columns depending on external flows, temperature, and other parameters
The granulocyte colony stimulating factor pathway regulates autoantibody production in a murine induced model of systemic lupus erythematosus
INTRODUCTION: An NZB-derived genetic locus (Sle2c2) that suppresses autoantibody production in a mouse model of induced systemic lupus erythematosus contains a polymorphism in the gene encoding the G-CSF receptor. This study was designed to test the hypothesis that the Sle2c2 suppression is associated with an impaired G-CSF receptor function that can be overcome by exogenous G-CSF. METHODS: Leukocytes from B6.Sle2c2 and B6 congenic mice, which carry a different allele of the G-CSF receptor, were compared for their responses to G-CSF. Autoantibody production was induced with the chronic graft-versus-host-disease (cGVHD) model by adoptive transfer of B6.bm12 splenocytes. Different treatment regimens varying the amount and frequency of G-CSF (Neulasta(®)) or carrier control were tested on cGVHD outcomes. Autoantibody production, immune cell activation, and reactive oxygen species (ROS) production were compared between the two strains with the various treatments. In addition, the effect of G-CSF treatment was examined on the production autoantibodies in the B6.Sle1.Sle2.Sle3 (B6.TC) spontaneous model of lupus. RESULTS: B6.Sle2c2 and B6 leukocytes responded differently to G-CSF. G-CSF binding by B6.Sle2c2 leukocytes was reduced as compared to B6, which was associated with a reduced expansion in response to in vivo G-CSF treatment. G-CSF in vivo treatment also failed to mobilize bone-marrow B6.Sle2c2 neutrophils as it did for B6 neutrophils. In contrast, the expression of G-CSF responsive genes indicated a higher G-CSF receptor signaling in B6.Sle2c2 cells. G-CSF treatment restored the ability of B6.Sle2c2 mice to produce autoantibodies in a dose-dependent manner upon cGVHD induction, which correlated with restored CD4(+ )T cells activation, as well as dendritic cell and granulocyte expansion. Steady-state ROS production was higher in B6.Sle2c2 than in B6 mice. cGVHD induction resulted in a larger increase in ROS production in B6 than in B6.Sle2c2 mice, and this difference was eliminated with G-CSF treatment. Finally, a low dose G-CSF treatment accelerated the production of anti-dsDNA IgG in young B6.TC mice. CONCLUSION: The different in vivo and in vitro responses of B6.Sle2c2 leukocytes are consistent with the mutation in the G-CSFR having functional consequences. The elimination of Sle2c2 suppression of autoantibody production by exogenous G-CSF indicates that Sle2c2 corresponds to a loss of function of G-CSF receptor. This result was corroborated by the increased anti-dsDNA IgG production in G-CSF-treated B6.TC mice, which also carry the Sle2c2 locus. Overall, these results suggest that the G-CSF pathway regulates the production of autoantibodies in murine models of lupus
CosmoScout VR: A Modular 3D Solar System Based on SPICE
We present CosmoScout VR - a modular 3D Solar System for interactive exploration and presentation of large space mission datasets. This paper describes the overall architecture as well as several core components of the frame-work. To foster the application in various scientific domains, CosmoScout VR employs a plugin-based architecture. This not only reduces development times but also allows scientists to create their own data visualization plugins without having to modify the core source code of CosmoScout VR. One of the most important plugins - level-of-detail terrain rendering - is described in greater detail in this paper. Another key feature of CosmoScout VR is the scene graph which is tightly coupled with NASA's SPICE library to allow for high-precision positioning of celestial objects, such as planets, moons, and spacecrafts. SPICE is also used for the seamless navigation throughout the Solar System in which the user automatically follows the closest body. During navigation, the virtual scene is scaled in such a way, that the closest celestial body is always within arm's reach. This allows for simultaneous exploration of multiple datasets in their spatial context at diverse scales. However, the navigation uses all six degrees of freedom which can induce motion sickness. In this paper, we present some counter measures as well as evaluate their effectiveness in a user study. CosmoScout VR is open source, cross-platform, and while it can run on conventional desktop PCs, it also supports stereoscopic multi-screen systems, such as display walls, DOMEs or CAVEs
Разработка рекомендаций к системе учета и контроля ядерных материалов, радиоактивных веществ и радиоактивных отходов в Томском политехническом университете
В работе представлен анализ существующей системы государственного учета и контроля ядерных материалов, радиоактивных веществ и радиоактивных отходов. На основе проведенного анализа текущего состояния нормативно-правовых документов установлено несоответствие и предложена рекомендация по изменению ряда документов ТПУ в области учета и контроля ядерных материалов.The paper presents an analysis of the existing system of state accounting and control of nuclear materials, radioactive substances and radioactive waste. Based on the analysis of the current state of regulatory documents, a discrepancy was established and a recommendation was proposed to amend a number of TPU documents in the field of accounting and control of nuclear materials
ESID: A Visual Analytics Tool to Epidemiological Emergencies
Visual analysis tools can help illustrate the spread of infectious diseases
and enable informed decisions on epidemiology and public health issues. To
create visualisation tools that are intuitive, easy to use, and effective in
communicating information, continued research and development focusing on
user-centric and methodological design models is extremely important. As a
contribution to this topic, this paper presents the design and development of
the visual analytics application ESID (Epidemiological Scenarios for Infectious
Diseases). The goal of ESID is to provide a platform for rapid assessment of
the most effective interventions for infectious disease control. ESID provides
spatial-temporal analysis, forecasting, comparison of simulations, interactive
filters, and accessibility options. In its current form, it shows the
simulations of a hybrid graph-equation-based model as introduced in for
infection control. The model can be stratified for different age groups and
takes into account the properties of the infectious disease as well as human
mobility and contact behaviour.Comment: 6 pages, 5 images and 1 table, Eurovis workshop on visual analytics
(EuroVA) 202
Анализ опасных производственных факторов при эксплуатации трансформаторов на электростанции
В данной статье проанализированы опасные факторы при работе электрической станции, также рассмотрены возможные последствия при взрыве трансформаторов, а также предложены мероприятия по снижению или искоренению возможных чрезвычайных ситуаций.This article analyzes the dangerous factors in the operation of the power plant, also considered the possible consequences of the explosion of transformers, as well as proposed measures to reduce or eliminate possible emergencies
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