62 research outputs found
АЛЬТЕРНАТИВНИЙ ЗАСІБ САНАЦІЇ РЕЗИДЕНТНИХ НОСІЇВ ЗОЛОТИСТОГО СТАФІЛОКОКА
The role of Staphylococcus aureus in the etiological structure of inflammatory infections is particularly important. The actual problem is the choice of a method of controlling bacteria carriers. One alternative way is the use of bacteriophages. The study was determined the sensitivity of Staphylococcus aureus strains, isolated from medical students of Kharkiv National Medical University, to the action of bacteriophages from various productions. This sensitivity was defined disco difuzinim method by bacteriophages such as: stafilofag (FSUE NPO "Microgen" MH RF c. Perm), piofag (FSUE NPO "Microgen" MH RF c. Nizhny Novgorod) and staphylococcal bacteriophage (Pharmaceutical Factory "Biofarm" Bila Cerkva, Ukraine). The results showed that more than half of the isolates S. aureus (68,75±6,69)% were sensitive to the stafilofag Ukrainian production to the piofag and stafilofag Russian production are low sensitivity (45,83±7,19) % and (22,9±6,06) %, accordingly.Роль золотистого стафілокока в етіологічній структурі гнійно-запальних інфекцій має особливе значення. Актуальною проблемою залишається вибір способу боротьби з бактеріоносіями. Одним з альтернативних шляхів є використання бактеріофагів. У ході дослідження була визначена чутливість штамів Staphylococcus аureus, вилучених від студентів-медиків Харківського національного медичного університету (ХНМУ), до дії бактеріофагів різних виробників. Чутливість визначали диско-дифузійним методом до таких бактеріофагів: стафілофаг (ФДУП «НВО «Микроген» МОЗ РФ, випуск м. Перм), піофаг (ФДУП «НВО «Микроген» МОЗ РФ, випуск м. Нижній Новгород) і стафілококовий бактеріофаг (фармацевтичний завод «Біофарм», м. Біла Церква, Україна). Результати дослідження показали, що більш ніж половина виділених штамів S. aureus, (68,75±6,69) %, були чутливими до стафілофага українського виробництва, до піофага та стафілофага російського виробника встановлена низька чутливість – (45,83±7,19) та (22,90±6,06) % відповідно
Повышение эффективности функционирования автоматических систем контроля, учета и управления энергопотреблением в условиях рынка двусторонних договоров и балансирующего рынка
В роботі обґрунтовується застосування автоматичних системи контролю, обліку та керування електроспоживанням (АСКОЕ) для керування попитом на електричну енергію в умовах ринку двосторонніх договорів та балансуючого ринку. Розглянуто склад АСКОЕ в загальному вигляді, призначення кожного компоненту системи. Наведено функціональну схему побудови пристроїв збирання та передавання даних (ПЗПД). Проведено аналіз вимог до апаратно-програмного забезпечення та шляхи вирішення існуючих проблем при побудові ПЗПД.This paper substantiates the application of the automatic systems of control, accounting and managing of power consumption to control the demand for electricity in a market of bilateral contracts and balancing market. Have been done the analysis of the constituent parts of the automatic systems of control, accounting and managing of power consumption and functions of each component of the system. The functional scheme of the devices collecting and transmitting data (RTU) are presented. Conducted the analysis of the hardware and software issues of RTU and submitted the solutions to the existing problems in constructing of the RTU.В работе обосновывается применение автоматических системы контроля, учета и управления электропотреблением (АСКУЭ) для управления спросом на электрическую энергию в условиях рынка двусторонних договоров и балансирующего рынка. Рассмотрены основные компоненты АСКУЭ в общем виде, назначение каждого компонента системы. Приведены функциональная схема построения устройств сбора и передачи данных (УСПД). Проведен анализ требований к аппаратно-программному обеспечению и пути решения существующих проблем при построении УСПД
Search for Cosmic-ray Boosted Sub-GeV Dark Matter using Recoil Protons at Super-Kamiokande
We report a search for cosmic-ray boosted dark matter with protons using the
0.37 megatonyears data collected at Super-Kamiokande experiment during
the 1996-2018 period (SKI-IV phase). We searched for an excess of proton
recoils above the atmospheric neutrino background from the vicinity of the
Galactic Center. No such excess is observed, and limits are calculated for two
reference models of dark matter with either a constant interaction
cross-section or through a scalar mediator. This is the first experimental
search for boosted dark matter with hadrons using directional information. The
results present the most stringent limits on cosmic-ray boosted dark matter and
exclude the dark matter-nucleon elastic scattering cross-section between
and for dark matter mass
from 10 MeV/ to 1 GeV/.Comment: With 1-page appendi
Measurement of the cosmogenic neutron yield in Super-Kamiokande with gadolinium loaded water
Cosmic-ray muons that enter the Super-Kamiokande detector cause hadronic
showers due to spallation in water, producing neutrons and radioactive
isotopes. Those are a major background source for studies of MeV-scale
neutrinos and searches for rare events. Since 2020, gadolinium was introduced
in the ultra-pure water in the Super-Kamiokande detector to improve the
detection efficiency of neutrons. In this study, the cosmogenic neutron yield
was measured using data acquired during the period after the gadolinium
loading. The yield was found to be at
259 GeV of average muon energy at the Super-Kamiokande detector.Comment: 10 pages, 10 figures, 3 table
Search for astrophysical electron antineutrinos in Super-Kamiokande with 0.01wt% gadolinium-loaded water
We report the first search result for the flux of astrophysical electron
antineutrinos for energies O(10) MeV in the gadolinium-loaded Super-Kamiokande
(SK) detector. In June 2020, gadolinium was introduced to the ultra-pure water
of the SK detector in order to detect neutrons more efficiently. In this new
experimental phase, SK-Gd, we can search for electron antineutrinos via inverse
beta decay with efficient background rejection and higher signal efficiency
thanks to the high efficiency of the neutron tagging technique. In this paper,
we report the result for the initial stage of SK-Gd with a exposure at 0.01% Gd mass concentration. No significant excess
over the expected background in the observed events is found for the neutrino
energies below 31.3 MeV. Thus, the flux upper limits are placed at the 90%
confidence level. The limits and sensitivities are already comparable with the
previous SK result with pure-water () owing
to the enhanced neutron tagging
Measurements of the charge ratio and polarization of cosmic-ray muons with the Super-Kamiokande detector
We present the results of the charge ratio () and polarization
() measurements using the decay electron events collected from
2008 September to 2022 June by the Super-Kamiokande detector. Because of its
underground location and long operation, we performed high precision
measurements by accumulating cosmic-ray muons. We measured the muon charge
ratio to be at
, where
is the muon energy and is the zenith angle
of incoming cosmic-ray muons. This result is consistent with the Honda flux
model while this suggests a tension with the model of . We
also measured the muon polarization at the production location to be
at the muon
momentum of at the surface of the
mountain; this also suggests a tension with the Honda flux model of
. This is the most precise measurement ever to experimentally
determine the cosmic-ray muon polarization near . These
measurement results are useful to improve the atmospheric neutrino simulations.Comment: 29 pages, 45 figure
Search for astrophysical electron antineutrinos in Super-Kamiokande with 0.01% gadolinium-loaded water
We report the first search result for the flux of astrophysical electron antineutrinos for energies (10) MeV in the gadolinium-loaded Super-Kamiokande (SK) detector. In 2020 June, gadolinium was introduced to the ultrapure water of the SK detector in order to detect neutrons more efficiently. In this new experimental phase, SK-Gd, we can search for electron antineutrinos via inverse beta decay with efficient background rejection thanks to the high efficiency of the neutron tagging technique. In this paper, we report the result for the initial stage of SK-Gd, during 2020 August 26, and 2022 June 1 with a 22.5 × 552 kton · day exposure at 0.01% Gd mass concentration. No significant excess over the expected background in the observed events is found for the neutrino energies below 31.3 MeV. Thus, the flux upper limits are placed at the 90% confidence level. The limits and sensitivities are already comparable with the previous SK result with pure water (22.5 × 2970 kton · day) owing to the enhanced neutron tagging. Operation with Gd increased to 0.03% started in 2022 June.DE-SC0015628 - Department of Energyhttp://10.0.15.7/2041-8213/acdc9
Diffuse supernova neutrino background search at Super-Kamiokande
A new search for the diffuse supernova neutrino background (DSNB) flux has
been conducted at Super-Kamiokande (SK), with a -ktonday
exposure from its fourth operational phase IV. The new analysis improves on the
existing background reduction techniques and systematic uncertainties and takes
advantage of an improved neutron tagging algorithm to lower the energy
threshold compared to the previous phases of SK. This allows for setting the
world's most stringent upper limit on the extraterrestrial flux,
for neutrino energies below 31.3 MeV. The SK-IV results are combined with the
ones from the first three phases of SK to perform a joint analysis using
ktondays of data. This analysis has the world's best
sensitivity to the DSNB flux, comparable to the predictions from
various models. For neutrino energies larger than 17.3 MeV, the new combined
C.L. upper limits on the DSNB flux lie around
cm, strongly disfavoring the most optimistic
predictions. Finally, potentialities of the gadolinium phase of SK and the
future Hyper-Kamiokande experiment are discussed.Comment: 42 pages, 37 figures, 14 table
Searching for supernova bursts in Super-Kamiokande IV
Super-Kamiokande has been searching for neutrino bursts characteristic of core-collapse supernovae continuously, in real time, since the start of operations in 1996. The present work focuses on detecting more distant supernovae whose event rate may be too small to trigger in real time, but may be identified using an offline approach. The analysis of data collected from 2008 to 2018 found no evidence of distant supernovae bursts. This establishes an upper limit of 0.29 yr−1 on the rate of core-collapse supernovae out to 100 kpc at 90% C.L. For supernovae that fail to explode and collapse directly to black holes the limit reaches to 300 kpc
Search for neutrinos in coincidence with gravitational wave events from the LIGO–Virgo O3a observing run with the Super-Kamiokande detector
The Super-Kamiokande detector can be used to search for neutrinos in time coincidence with gravitational waves detected by the LIGO–Virgo Collaboration (LVC). Both low-energy (7–100 MeV) and high-energy (0.1–105 GeV) samples were analyzed in order to cover a very wide neutrino spectrum. Follow-ups of 36 (out of 39) gravitational waves reported in the GWTC-2 catalog were examined; no significant excess above the background was observed, with 10 (24) observed neutrinos compared with 4.8 (25.0) expected events in the high-energy (low-energy) samples. A statistical approach was used to compute the significance of potential coincidences. For each observation, p-values were estimated using neutrino direction and LVC sky map; the most significant event (GW190602_175927) is associated with a post-trial p-value of 7.8% (1.4σ). Additionally, flux limits were computed independently for each sample and by combining the samples. The energy emitted as neutrinos by the identified gravitational wave sources was constrained, both for given flavors and for all flavors assuming equipartition between the different flavors, independently for each trigger and by combining sources of the same nature
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