22 research outputs found

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

    Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

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    Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

    Ultralight vector dark matter search using data from the KAGRA O3GK run

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    Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Eco-innovative competencies of mining engineers in the context of environmental management system requirements

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    The article is devoted to the analysis of mining engineers’ eco-innovation training key components associated with the formation of special knowledge and skills in the field of coal mining enterprises environmental management. The issues of the eco-innovation activities and the objectives of environmental management at coal mining enterprises are consistently considered. The article presents the examination of general and special requirements for the environmental education of mining engineers, which are to become the basis for the sustainable development of engineering projects in coal-mining industry

    THE CONTENT OF CD4+ AND CD8+ EFFECTOR MEMORY CELLS AND THE PROLIFERATIVE ACTIVITY OF T LYMPHOCYTES IN BRONCHIAL ASTHMA

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    Bronchial asthma is a chronic inflammatory disease of the respiratory tract. T-lymphocytes play a key role in the pathogenesis of this allergic disease. The reduction in number of naive T cells and the accumulation of memory T cells in bronchial asthma are accompanied by dysregulation of T lymphocytes function. In present study, it was investigated the content of different subpopulations of T lymphocytes in the peripheral blood, in unstimulated and PHA-stimulated cultures, as well as their proliferative capacity in patients with bronchial asthma and healthy donors. The study included 10 patients with bronchial asthma (age 45.4 ± 11.8 years). One half of patients was in remission and the other half - in the stage of exacerbation of the underlying disease. The group of donors was formed by healthy individuals matched by gender and age to patients. Based on the expression of cell surface markers CD45R0, CD62L and CD197 (CCR7) CD4+ and CD8+ T lymphocytes were divided into central (Tcm) and effector memory cells (Tem), naive T-lymphocytes (Tnaive) and terminal-differentiated effectors (Temra) using flow cytometric technique. The proliferative activity of Tcm, Tem and Tnaive was evaluated in response to PHA as a functional marker of T cells. It was found that the percentage of CD4+TemCD62L+ and CD8+TemCD62L+ in the peripheral blood of patients in the exacerbation of asthma was significantly reduced compared to donors. After stimulation with PHA, these differences in T cell subsets between the groups of patients and donors were disappeared. We performed a correlation analysis between memory T cells and age . It was determined that the relative amount of CD4+ and CD8+ memory cells increased with age in asthmatics, but not in healthy donors. The analysis of mitogen-induced proliferation showed that Tcm and Tnaive cells divided more actively compared to other subpopulations in both groups. At the same time, the proliferative activity of CD4+ T lymphocytes and subsets of CD8+Tcm, CD4+Tcm and CD4+Tem62L- was higher in the group of patients in remission of asthma, than in groups of patients in exacerbation of the disease, and healthy donors. The revealed increase in the relative number of memory T cells with age suggests that these cells participate in the development of bronchial asthma. The proliferative response of the studied subpopulations, which was comparable with the donor values, indicates the retention of the functional characteristics of memory T cells and naive T lymphocytes in bronchial asthma. The increased proliferation of some T-cell subpopulations in asthmatics in remission points to the activated state of memory T cells. The observed decrease in the number of CD4+TemCD62L+ and CD8+TemCD62L+ in patients in exacerbation of asthma, by our opinion, may be associated with an active inflammatory process in the airways

    Mechanochemically Obtained Phytobiotics Suppress the Development of Pathogens

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    Проведено исследование бактерицидного действия ряда фитопрепаратов, полученных в результате механохимической обработки смесей растительного сырья с твердым карбонатом натрия в отношении условно-патогенных бактерий Salmonella typhimurium, Shigella sonnei, Esherichia coli, Pasteurella multocida, Yersinia pseudotuberculosis, Streptococcu spyogenes, Staphylococcus aureus, Staphylococcu sepidermidis, Proteus vulgaris, Proteus mirabilis. Исследованные фитопрепараты характеризуются селективным воздействием на один – три вида микроорганизмов. Обнаружен эффект аддитивного действия фитопрепаратов в смеси, который может быть в дальнейшем использован вне смесей для профилактики и терапии конкретных случаев заболевания животных и человека с установленной бактериальной этиологиейA study of the bactericidal action of a number of phytopreparations obtained as a result of mechanochemical treatment of mixtures of plant raw materials with solid sodium carbonate in relation to 10 species of opportunistic bacteria was carried out. The investigated phytopreparations have a selective effect on 1-3 types of microorganisms. The effect of the additive action of phytopreparations in mixtures, which can be used for the prevention and treatment of diseases of animals and humans with an established bacterial etiology, has been discovere
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