345 research outputs found

    A flaring X-ray pulsar in Dorado

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    A study of unusual gamma-ray bursts detected on March 5 and March 6, 1979 in the KONUS experiment on the Venera 11 and Venera 12 spacecraft shows their source to be flaring X-ray pulsar in Dorado

    Preliminary results of a gamma-ray burst study in the Konus experiment on the Venera-11 and Venera-12 space probes

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    Twenty-one gamma-ray bursts and 68 solar flares in the hard X-ray range were detected on Venera-11 and Venera-12 space probes during the initial 50-day observation period. Major characteristics of the equipment used and preliminary data on the temporal structure and energy spectra of the gamma-ray bursts are considered. The pattern of gamma-ray burst frequency distribution vs. intensity, N(S), is established

    Risk of Venous Thromboembolic Complications in Patients with Atrial Fibrillation: a Systematic Review and Meta-analysis

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    Aim: The aim of this meta-analysis and systematic review was to evaluate the possible connection between AF and VTE.Material and methods. Atrial fibrillation (AF) and atrial flutter (AFL) contribute to intra-atrial blood stasis which leads to thrombus formation with its embolization. There is some evidence that AF can be a risk factor for deep vein thrombosis (DVT) and pulmonary embolism (PE). The following databases were searched: PubMed (MEDLINE), EMBASE, Google Scholar, the Cochrane Central Register of Controlled Trials. The time frame for conducting a systematic literature search ranged from January 1, 1990 to November 1, 2021. The diagnosis of atrial fibrillation had to be confirmed by using ECG. The diagnosis of VTE could be made with Doppler imaging, ventilation/perfusion scan, CT angiography, venography, angiography or autopsy. Only the three studies with 102192 patients meeting the requirement were included in the meta-analysis.Results. The prevalence of DVT and PE were assessed using incidence rate ratios (IRR) method of the inverse variance random effects model and its 95% confidence interval (CI). The significant association between atrial fibrillation and pulmonary embolism was found (IRR, 4.18 95% Cl 1.958.98). Also there is obvious association between DVT and AF (IRR, 2.97 95% Cl 2.18-4.03).Conclusion. It can be concluded that the increased risk of developing VTE is associatedwith concomitant AF

    The optical identifcation of events with poorly defined locations: The case of the Fermi GBM GRB140801A

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    We report the early discovery of the optical afterglow of gamma-ray burst (GRB) 140801A in the 137 deg2^2 3-Οƒ\sigma error-box of the Fermi Gamma-ray Burst Monitor (GBM). MASTER is the only observatory that automatically react to all Fermi alerts. GRB 140801A is one of the few GRBs whose optical counterpart was discovered solely from its GBM localization. The optical afterglow of GRB 140801A was found by MASTER Global Robotic Net 53 sec after receiving the alert, making it the fastest optical detection of a GRB from a GBM error-box. Spectroscopy obtained with the 10.4-m Gran Telescopio Canarias and the 6-m BTA of SAO RAS reveals a redshift of z=1.32z=1.32. We performed optical and near-infrared photometry of GRB 140801A using different telescopes with apertures ranging from 0.4-m to 10.4-m. GRB 140801A is a typical burst in many ways. The rest-frame bolometric isotropic energy release and peak energy of the burst is Eiso=5.54βˆ’0.24+0.26Γ—1052E_\mathrm{iso} = 5.54_{-0.24}^{+0.26} \times 10^{52} erg and Ep,rest≃280E_\mathrm{p, rest}\simeq280 keV, respectively, which is consistent with the Amati relation. The absence of a jet break in the optical light curve provides a lower limit on the half-opening angle of the jet ΞΈ=6.1\theta=6.1 deg. The observed EpeakE_\mathrm{peak} is consistent with the limit derived from the Ghirlanda relation. The joint Fermi GBM and Konus-Wind analysis shows that GRB 140801A could belong to the class of intermediate duration. The rapid detection of the optical counterpart of GRB 140801A is especially important regarding the upcoming experiments with large coordinate error-box areas.Comment: in press MNRAS, 201

    Acute WNT signalling activation perturbs differentiation within the adult stomach and rapidly leads to tumour formation

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    A role for WNT signalling in gastric carcinogenesis has been suggested due to two major observations. First, patients with germline mutations in adenomatous polyposis coli (APC) are susceptible to stomach polyps and second, in gastric cancer, WNT activation confers a poor prognosis. However, the functional significance of deregulated WNT signalling in gastric homoeostasis and cancer is still unclear. In this study we have addressed this by investigating the immediate effects of WNT signalling activation within the stomach epithelium. We have specifically activated the WNT signalling pathway within the mouse adult gastric epithelium via deletion of either glycogen synthase kinase 3 (GSK3) or APC or via expression of a constitutively active Ξ²-catenin protein. WNT pathway deregulation dramatically affects stomach homoeostasis at very short latencies. In the corpus, there is rapid loss of parietal cells with fundic gland polyp (FGP) formation and adenomatous change, which are similar to those observed in familial adenomatous polyposis. In the antrum, adenomas occur from 4 days post-WNT activation. Taken together, these data show a pivotal role for WNT signalling in gastric homoeostasis, FGP formation and adenomagenesis. Loss of the parietal cell population and corresponding FGP formation, an early event in gastric carcinogenesis, as well as antral adenoma formation are immediate effects of nuclear Ξ²-catenin translocation and WNT target gene expression. Furthermore, our inducible murine model will permit a better understanding of the molecular changes required to drive tumourigenesis in the stomach

    Salinity modulates thermotolerance, energy metabolism and stress response in amphipods Gammarus lacustris

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    Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase) and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate). Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming) was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress

    ВозмоТности ΠΎΡ†Π΅Π½ΠΊΠΈ систСмы гСмостаза ΠΏΡ€ΠΈ фибрилляции прСдсСрдий ΠΈ Ρ‚Ρ€ΠΎΠΌΠ±ΠΎΠ·Π΅ ΡƒΡˆΠΊΠ° Π»Π΅Π²ΠΎΠ³ΠΎ прСдсСрдия

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    Thromboembolic syndrome, the frequency of which is 8–15%, is the main danger for a patient with atrial fibrillation (AF). The left atrial appendage is the most common source of thromboembolia in atrial fibrillation. The frequency of detection of left atrial appendage thrombus in AF is 15.2% in the absence of anticoagulant therapy and 1–8% in patients using this group of drugs. The reason for the formation of thrombi in this localization during anticoagulant therapy today it is not reliably known. This article describes a clinical case of a 67-year-old patient with persistent AF and left atrial appendage thrombosis, who was hospitalized to determine further management strategies. A left atrial appendage thrombus lasted for a year despite continuous anticoagulant therapy with various oral anticoagulants at doses consistent with clinical guidelines due to the patient's absolute refusal to take warfarin, vitamin K antagonist. In addition, this article discusses the use of Thrombodynamics, a new global coagulation test, in patients with AF, which revealed a plasma hypercoagulable state with underlying persistent thrombosis in this patient on continuous oral anticoagulant treatment. The Thrombodynamics test is a promising procedure for assessing the coagulation system state and may be promising as a method for measuring the effectiveness of any oral anticoagulant. However, it is impossible to draw any definite conclusions on the basis of single observations; large clinical studies with the potential of long-term case follow-up of patients are needed.ΠžΡΠ½ΠΎΠ²Π½ΡƒΡŽ ΠΎΠΏΠ°ΡΠ½ΠΎΡΡ‚ΡŒ ΠΏΡ€ΠΈ фибрилляции прСдсСрдий (ЀП) для ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚Π° прСдставляСт тромбоэмболичСский синдром, частота ΠΊΠΎΡ‚ΠΎΡ€ΠΎΠ³ΠΎ составляСт 8–15%. НаиболСС частым источником тромбоэмболии ΠΏΡ€ΠΈ фибрилляции прСдсСрдий являСтся ΡƒΡˆΠΊΠΎ Π»Π΅Π²ΠΎΠ³ΠΎ прСдсСрдия. Частота выявлСния Ρ‚Ρ€ΠΎΠΌΠ±Π° Π² полости ΡƒΡˆΠΊΠ° Π»Π΅Π²ΠΎΠ³ΠΎ прСдсСрдия ΠΏΡ€ΠΈ ЀП составляСт 15,2% ΠΏΡ€ΠΈ отсутствии антикоагулянтной Ρ‚Π΅Ρ€Π°ΠΏΠΈΠΈ ΠΈ 1–8% Ρƒ ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ² Π½Π° Ρ„ΠΎΠ½Π΅ ΠΏΡ€ΠΈΠ΅ΠΌΠ° ΠΏΡ€Π΅ΠΏΠ°Ρ€Π°Ρ‚ΠΎΠ² этой Π³Ρ€ΡƒΠΏΠΏΡ‹. ΠŸΡ€ΠΈΡ‡ΠΈΠ½Π° формирования Ρ‚Ρ€ΠΎΠΌΠ±ΠΎΠ² Π΄Π°Π½Π½ΠΎΠΉ Π»ΠΎΠΊΠ°Π»ΠΈΠ·Π°Ρ†ΠΈΠΈ Π½Π° Ρ„ΠΎΠ½Π΅ антикоагулянтной Ρ‚Π΅Ρ€Π°ΠΏΠΈΠΈ ΠΊ настоящСму Π²Ρ€Π΅ΠΌΠ΅Π½ΠΈ достовСрно нСизвСстна. Π’ Π΄Π°Π½Π½ΠΎΠΉ ΡΡ‚Π°Ρ‚ΡŒΠ΅ описываСтся клиничСскоС наблюдСниС ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΊΠΈ 67 Π»Π΅Ρ‚ с ΠΏΠ΅Ρ€ΡΠΈΡΡ‚ΠΈΡ€ΡƒΡŽΡ‰Π΅ΠΉ Ρ„ΠΎΡ€ΠΌΠΎΠΉ ЀП ΠΈ Ρ‚Ρ€ΠΎΠΌΠ±ΠΎΠ·ΠΎΠΌ ΡƒΡˆΠΊΠ° Π»Π΅Π²ΠΎΠ³ΠΎ прСдсСрдия, которая Π±Ρ‹Π»Π° госпитализирована для опрСдСлСния дальнСйшСй Ρ‚Π°ΠΊΡ‚ΠΈΠΊΠΈ вСдСния. Π’Ρ€ΠΎΠΌΠ± Π² ΡƒΡˆΠΊΠ΅ Π»Π΅Π²ΠΎΠ³ΠΎ прСдсСрдия сохранялся Π² Ρ‚Π΅Ρ‡Π΅Π½ΠΈΠ΅ Π³ΠΎΠ΄Π°, нСсмотря Π½Π° ΠΏΡ€ΠΎΠ²ΠΎΠ΄ΠΈΠΌΡƒΡŽ Π°Π½Ρ‚ΠΈΠΊΠΎΠ°Π³ΡƒΠ»ΡΠ½Ρ‚Π½ΡƒΡŽ Ρ‚Π΅Ρ€Π°ΠΏΠΈΡŽ Ρ€Π°Π·Π»ΠΈΡ‡Π½Ρ‹ΠΌΠΈ ΠΏΠ΅Ρ€ΠΎΡ€Π°Π»ΡŒΠ½Ρ‹ΠΌΠΈ антикоагулянтами Π² Π΄ΠΎΠ·Π°Ρ…, ΡΠΎΠΎΡ‚Π²Π΅Ρ‚ΡΡ‚Π²ΡƒΡŽΡ‰ΠΈΡ… клиничСским рСкомСндациям Π²Π²ΠΈΠ΄Ρƒ Π°Π±ΡΠΎΠ»ΡŽΡ‚Π½ΠΎΠ³ΠΎ ΠΎΡ‚ΠΊΠ°Π·Π° ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΊΠΈ ΠΎΡ‚ ΠΏΡ€ΠΈΠ΅ΠΌΠ° антагониста Π²ΠΈΡ‚Π°ΠΌΠΈΠ½Π° К Π²Π°Ρ€Ρ„Π°Ρ€ΠΈΠ½Π°. ΠšΡ€ΠΎΠΌΠ΅ Ρ‚ΠΎΠ³ΠΎ, Π² Π΄Π°Π½Π½ΠΎΠΉ ΡΡ‚Π°Ρ‚ΡŒΠ΅ обсуТдаСтся ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ Π½ΠΎΠ²ΠΎΠ³ΠΎ глобального тСста Β«Π’Ρ€ΠΎΠΌΠ±ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΠΊΠ°Β» Ρƒ ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ² с ЀП, ΠΊΠΎΡ‚ΠΎΡ€Ρ‹ΠΉ продСмонстрировал Ρƒ Π΄Π°Π½Π½ΠΎΠΉ ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΊΠΈ состояниС гипСркоагуляции ΠΏΠ»Π°Π·ΠΌΡ‹ ΠΊΡ€ΠΎΠ²ΠΈ Π½Π° Ρ„ΠΎΠ½Π΅ ΠΏΡ€ΠΎΠ΄ΠΎΠ»ΠΆΠ°ΡŽΡ‰Π΅ΠΉΡΡ антикоагулянтной Ρ‚Π΅Ρ€Π°ΠΏΠΈΠΈ ΠΈ ΠΏΠ΅Ρ€ΡΠΈΡΡ‚ΠΈΡ€ΡƒΡŽΡ‰Π΅Π³ΠΎ Ρ‚Ρ€ΠΎΠΌΠ±ΠΎΠ·Π°. ВСст Β«Π’Ρ€ΠΎΠΌΠ±ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΠΊΠ°Β» прСдставляСт собой ΠΌΠ½ΠΎΠ³ΠΎΠΎΠ±Π΅Ρ‰Π°ΡŽΡ‰ΡƒΡŽ ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΈΠΊΡƒ для ΠΎΡ†Π΅Π½ΠΊΠΈ состояния ΡΠ²Π΅Ρ€Ρ‚Ρ‹Π²Π°ΡŽΡ‰Π΅ΠΉ систСмы ΠΊΡ€ΠΎΠ²ΠΈ ΠΈ ΠΌΠΎΠΆΠ΅Ρ‚ Π±Ρ‹Ρ‚ΡŒ пСрспСктивным Π² качСствС ΠΌΠ΅Ρ‚ΠΎΠ΄Π° измСрСния эффСктивности любого ΠΏΠ΅Ρ€ΠΎΡ€Π°Π»ΡŒΠ½ΠΎΠ³ΠΎ антикоагулянта. Однако Π½Π° основании Π΅Π΄ΠΈΠ½ΠΈΡ‡Π½Ρ‹Ρ… наблюдСний Π½Π΅Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ Π΄Π΅Π»Π°Ρ‚ΡŒ ΠΊΠ°ΠΊΠΈΠ΅-Π»ΠΈΠ±ΠΎ ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½Π½Ρ‹Π΅ Π²Ρ‹Π²ΠΎΠ΄Ρ‹, Π½Π΅ΠΎΠ±Ρ…ΠΎΠ΄ΠΈΠΌΡ‹ ΠΊΡ€ΡƒΠΏΠ½Ρ‹Π΅ клиничСскиС исслСдования с Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡ‚ΡŒΡŽ Π΄Π»ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠ³ΠΎ динамичСского наблюдСния Π·Π° ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚Π°ΠΌΠΈ

    The influence of salinity on the effects of Multi-walled carbon nanotubes on polychaetes

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    Salinity shifts in estuarine and coastal areas are becoming a topic of concern and are one of the main factors influencing nanoparticles behaviour in the environment. For this reason, the impacts of multiwalled carbon nanotubes (MWCNTs) under different seawater salinity conditions were evaluated on the common ragworm Hediste diversicolor, a polychaete species widely used as bioindicator of estuarine environmental quality. An innovative method to assess the presence of MWCNT aggregates in the sediments was used for the first time. Biomarkers approach was used to evaluate the metabolic capacity, oxidative status and neurotoxicity of polychaetes after long-term exposure. The results revealed an alteration of energy-related responses in contaminated polychaetes under both salinity conditions, resulting in an increase of metabolism and expenditure of their energy reserves (lower glycogen and protein contents). Moreover, a concentration-dependent toxicity (higher lipid peroxidation, lower ratio between reduced and oxidized glutathione and activation of antioxidant defences and biotransformation mechanisms) was observed in H. diversicolor, especially when exposed to low salinity. Additionally, neurotoxicity was observed by inhibition of Cholinesterases activity in organisms exposed to MWCNTs at both salinities.publishe

    Biomethanation potential of biological and other wastes

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    Anaerobic technology has been traditionally applied for the treatment of carbon rich wastewater and organic residues. Anaerobic processes can be fully integrated in the biobased economy concept for resource recovery. After a brief introduction about applications of anaerobic processes to industrial wastewater treatment, agriculture feedstock and organic fraction of municipal solid waste, the position of anaerobic processes in biorefinery concepts is presented. Integration of anaerobic digestion with these processes can help in the maximisation of the economic value of the biomass used, while reducing the waste streams produced and mitigating greenhouse gases emissions. Besides the integration of biogas in the existing full-scale bioethanol and biodiesel production processes, the potential applications of biogas in the second generation lignocellulosic, algae and syngas-based biorefinery platforms are discussed.(undefined
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