No news for Kerr-Schild fields

Algebraically special fields with no gravitational radiation are described. Kerr-Schild fields, which include as a concrete case the Kinnersley photon rocket, form an important subclass of them.Comment: 4 pages, Revtex

ЭЛЕКТРОТЕХНОЛОГИЯ ПОЛУЧЕНИЯ СИНТЕЗ-ГАЗА С ИСПОЛЬЗОВАНИЕМ ОБЪЁМНЫХ ВЫСОКОВОЛЬТНЫХ ИМПУЛЬСНЫХ РАЗРЯДОВ: КОРОННОГО И БАРЬЕРНОГО

Factory testing of a created high-voltage complex (plant) has been conducted. The complex consists of two pulse generators with the repetition rate of up to 50,000 pulses per second and load reactors with pulsed discharges – corona and barrier ones. Transistor (IGBT) keys are used as energy switches. The efficient mode of coke gas methane conversion (steam reforming) to syngas has been obtained with application of the complex created. A unidirectional action of the pulsed discharges, the gas mixture temperature, and a nickel catalyst has reduced the specific energy consumption for synthesis gas regeneration during the conversion. A feasible mechanism of this conversion is described.В заводских условиях проведена апробация созданного высоковольтного комплекса (установки), состоящего из двух генераторов импульсов с частотой следования до 50000 имп/с и нагрузки в виде реакторов с импульсными разрядами – коронным и барьерным. В качестве коммутаторов энергии использованы транзисторные (IGBT) ключи. Получен рациональный режим конверсии (парового риформинга) метана в составе коксового газа в синтез-газ при помощи созданной установки. Для уменьшения удельных энергозатрат на получение синтез-газа при конверсии использовано однонаправленное действие импульсных разрядов, температуры парогазовой смеси и никелевого катализатора. Описан возможный механизм такой конверсии.В заводських умовах проведено апробацію створеного високовольтного комплексу (установки), який складається з двох генераторів імпульсів з частотою проходження імпульсів до 50000 імп/с і навантаження у вигляді реакторів з імпульсними розрядами – коронним і бар’єрним. У якості комутаторів енергії використано транзисторні (IGBT) ключі. Отримано раціональний режим конверсії (парового риформінгу) метану у складі коксового газу в синтез-газ за допомогою створеної установки. Для зменшення питомих енерговитрат на одержання синтез-газу при конверсії використано односпрямовану дію імпульсних розрядів, температури парогазової суміші і нікелевого каталізатора. Описано можливий механізм такої конверсії

Electrophysical properties of nanoporous cerium dioxide–water system

The impedance of nanoporous cerium dioxide with adsorbed water is investigated in the frequency range 103–104 Hz at temperatures near the water–ice phase transition. Here we show that the manifestation of impedance peculiarities at phase transition is caused by the dielectric constant of the matrix

A review of career devoted to biophotonics-in memoriam to Ekaterina Borisova (1978-2021)

Regretfully, because of her sudden demise, Assoc. Prof. Ekaterina Borisova is no longer amongst us. COVID-19 pulled away a brilliant scientist during the peak of her scientific career (see Fig. 1). All authors would like to express deepest condolences and sincere support to her family, friends, relatives and colleagues! We, therefore, rightfully commemorate her dedicated and devoted contribution to biophotonics, her readiness to always support, help, motivate and inspire all her colleagues and collaborators

Search for W W/W Z resonance production in ℓνqq final states in pp collisions at √s=13 TeV with the ATLAS detector

A search is conducted for new resonances decaying into a W W or W Z boson pair, where one W boson decays leptonically and the other W or Z boson decays hadronically. It is based on proton-proton collision data with an integrated luminosity of 36.1 fb −1 collected with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of s=13 TeV in 2015 and 2016. The search is sensitive to diboson resonance production via vector-boson fusion as well as quark-antiquark annihilation and gluon-gluon fusion mechanisms. No significant excess of events is observed with respect to the Standard Model backgrounds. Several benchmark models are used to interpret the results. Limits on the production cross section are set for a new narrow scalar resonance, a new heavy vector-boson and a spin-2 Kaluza-Klein graviton.[Figure not available: see fulltext.]

Search for heavy resonances decaying into WW in the eνμν eνμν final state in pp collisions at √s=13 TeV with the ATLAS detector

A search for neutral heavy resonances is performed in the WW→eνμν decay channel using pp collision data corresponding to an integrated luminosity of 36.1fb−1, collected at a centre-of-mass energy of 13TeV by the ATLAS detector at the Large Hadron Collider. No evidence of such heavy resonances is found. In the search for production via the quark–antiquark annihilation or gluon–gluon fusion process, upper limits on σX×B(X→WW) as a function of the resonance mass are obtained in the mass range between 200GeV GeV and up to 5TeV for various benchmark models: a Higgs-like scalar in different width scenarios, a two-Higgs-doublet model, a heavy vector triplet model, and a warped extra dimensions model. In the vector-boson fusion process, constraints are also obtained on these resonances, as well as on a Higgs boson in the Georgi–Machacek model and a heavy tensor particle coupling only to gauge bosons

Measurement of the branching ratio Γ(Λb⁰ → ψ(2S)Λ0)/Γ(Λb⁰ → J/ψΛ0) with the ATLAS detector

An observation of the $\Lambda_b^0 \rightarrow \psi(2S) \Lambda^0$ decay and a comparison of its branching fraction with that of the $\Lambda_b^0 \rightarrow J/\psi \Lambda^0$ decay has been made with the ATLAS detector in proton--proton collisions at $\sqrt{s}=8\,$TeV at the LHC using an integrated luminosity of $20.6\,$fb$^{-1}$. The $J/\psi$ and $\psi(2S)$ mesons are reconstructed in their decays to a muon pair, while the $\Lambda^0\rightarrow p\pi^-$ decay is exploited for the $\Lambda^0$ baryon reconstruction. The $\Lambda_b^0$ baryons are reconstructed with transverse momentum $p_{\rm T}>10\,$GeV and pseudorapidity $|\eta|<2.1$. The measured branching ratio of the $\Lambda_b^0 \rightarrow \psi(2S) \Lambda^0$ and $\Lambda_b^0 \rightarrow J/\psi \Lambda^0$ decays is $\Gamma(\Lambda_b^0 \rightarrow \psi(2S)\Lambda^0)/\Gamma(\Lambda_b^0 \rightarrow J/\psi\Lambda^0) = 0.501\pm 0.033 ({\rm stat})\pm 0.019({\rm syst})$, lower than the expectation from the covariant quark model.Comment: 12 pages plus author list (28 pages total), 5 figures, 1 table, published on Physics Letters B 751 (2015) 63-80. All figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/BPHY-2013-08

It is time to define an organizational model for the prevention and management of infections along the surgical pathway: a worldwide cross-sectional survey

Background The objectives of the study were to investigate the organizational characteristics of acute care facilities worldwide in preventing and managing infections in surgery; assess participants' perception regarding infection prevention and control (IPC) measures, antibiotic prescribing practices, and source control; describe awareness about the global burden of antimicrobial resistance (AMR) and IPC measures; and determine the role of the Coronavirus Disease 2019 pandemic on said awareness. Methods A cross-sectional web-based survey was conducted contacting 1432 health care workers (HCWs) belonging to a mailing list provided by the Global Alliance for Infections in Surgery. The self-administered questionnaire was developed by a multidisciplinary team. The survey was open from May 22, 2021, and June 22, 2021. Three reminders were sent, after 7, 14, and 21 days. Results Three hundred four respondents from 72 countries returned a questionnaire, with an overall response rate of 21.2%. Respectively, 90.4% and 68.8% of participants stated their hospital had a multidisciplinary IPC team or a multidisciplinary antimicrobial stewardship team. Local protocols for antimicrobial therapy of surgical infections and protocols for surgical antibiotic prophylaxis were present in 76.6% and 90.8% of hospitals, respectively. In 23.4% and 24.0% of hospitals no surveillance systems for surgical site infections and no monitoring systems of used antimicrobials were implemented. Patient and family involvement in IPC management was considered to be slightly or not important in their hospital by the majority of respondents (65.1%). Awareness of the global burden of AMR among HCWs was considered very important or important by 54.6% of participants. The COVID-19 pandemic was considered by 80.3% of respondents as a very important or important factor in raising HCWs awareness of the IPC programs in their hospital. Based on the survey results, the authors developed 15 statements for several questions regarding the prevention and management of infections in surgery. The statements may be the starting point for designing future evidence-based recommendations. Conclusion Adequacy of prevention and management of infections in acute care facilities depends on HCWs behaviours and on the organizational characteristics of acute health care facilities to support best practices and promote behavioural change. Patient involvement in the implementation of IPC is still little considered. A debate on how operationalising a fundamental change to IPC, from being solely the HCWs responsibility to one that involves a collaborative relationship between HCWs and patients, should be opened

КОМПАКТНЫЙ ЁМКОСТНЫЙ ДЕЛИТЕЛЬ НАПРЯЖЕНИЯ НА 70 КВ С ЭКРАНИРОВАННЫМ ПРОМЕЖУТОЧНЫМ ЭЛЕКТРОДОМ

A compact capacitive voltage divider with dividing coefficient Kcdv=7653 is created, successfully tested and put into operation. The divider is intended for operation with various-form voltage of the amplitude up to 70 kV, the transient characteristic rise time not exceeding 1,5 ns. The divider diameter is 200 mm, its length is 175 mm and the mass is 1,27 kg.На основе сформулированных принципов создан, успешно испытан и введен в эксплуатацию компактный ёмкостный делитель напряжения с коэффициентом деления КЕДН=7653. Делитель рассчитан на работу с напряжениями различной формы при амплитуде до 70 кВ, имеет время нарастания переходной характеристики не более 1,5 нс. Диаметр делителя – 200 мм, длина – 175 мм, масса – 1,27 кг.На основі сформульованих принципів створено, успішно випробувано і введено в експлуатацію компактний ємнісний дільник напруги з коефіцієнтом ділення КЄДН=7653. Дільник розраховано на роботу з напругами різної форми при амплітуді до 70 кВ. Він має час наростання перехідної характеристики не більше 1,5 нс. Діаметр дільника – 200 мм, довжина – 175 мм, маса – 1,27 кг