24 research outputs found
ИЗВЛЕЧЕНИЕ МАССЫ НЕЙТРИНО ИЗ УГЛОВОЙ АСИММЕТРИИ ЭЛЕКТРОНОВ β-РАСПАДА
The mass of electron antineutrinos in laboratory experiments is extracted from the analysis of the energy spectrum of electrons emitted during the beta decay of nuclei and nucleons. Since the total probability of the electron emission is proportional to the square of the matrix element of nucleons and nuclei, the effect of their internal structure on a very small amount of antineutrino mass (1 eV or less) turns out to be significant. This effect can be minimized by measuring the relative characteristics (particle polarizations, angular asymmetries) in pure Fermi and pure gam-Teller transitions. In this case, the full matrix elements are factorized (represented as a product of lepton and nucleon scalar functions, but not tensors), which leads to a reduction of poorly known nucleon structure functions in the numerator and denominator of all formulas for the degrees of polarizations and coefficients of lepton asymmetries.В лабораторных условиях массу электронных антинейтрино извлекают из анализа энергетического спектра электронов, испускаемых при бета-распаде ядер и нуклонов. Поскольку полная вероятность вылета электронов пропорциональна квадрату матричного элемента нуклонов и ядер, то влияние их внутренней структуры на очень малую величину массы антинейтрино (1 эВ и меньше) оказывается существенным. Можно минимизировать это влияние если измерять относительные характеристики (поляризации частиц, угловые асимметрии) в чистых фермиевских и чистых гамов-теллеровских переходах. В этом случае полные матричные элементы факторизуются (представляются в виде произведения лептонных и нуклонных скалярных функций, но не тензоров), что приводит к сокращению, плохо изученных нуклонных структурных функций в числителе и знаменателе всех формул для степеней поляризаций и коэффициентов асимметрий вылета лептонов
On the possibility of determining antineutrino mass by measuring relative characteristics in β-decay processes
An influence of the neutrino (antineutrino) mass on the characteristics of nuclei and neutron β-deca y is demonstr ated. It has been shown that meas uring relative character istics allows one to get rid of the unknown nuclear structure, which makes it possible to determine the magnitude of the neutrino (antineutrino) mass in the β-decay processes with greater accuracy. An analysis was carried out based on general theoretical formulas for differential probabilities of the β-decays of the free neutron and tritium nucleus. As a result, it was possible to obtain simple formulas from which a theoretical estimation for the neutrino (antineutrino) rest mass can be obtained. © Published under licence by IOP Publishing Ltd
О ВОЗМОЖНОСТИ ОПРЕДЕЛЕНИЯ МАССЫ АНТИНЕЙТРИНО ПО ИЗМЕРЕНИЮ ОТНОСИТЕЛЬНЫХ ХАРАКТЕРИСТИК (ПОЛЯРИЗАЦИЙ И АСИММЕТРИЙ) В ПРОЦЕССАХ β-РАСПАД
The influence of antineutrino mass on the characteristics of beta decay of nuclei and a neutron is demonstrated. It is shown that the measurement of relative characteristics allows to get rid of the poorly studied nuclear structure, and also the possibility of determining the mass of antineutrinos (neutrinos) in β-decay processes by measuring polarizations and asymmetries is presented. The analysis was carried out on the basis of theoretical formulas for the differential probabilities of decay processes. As a result, it was possible to obtain a formula for the theoretical estimate of the antineutrino mass value.Продемонстрировано влияние массы антинейтрино на характеристики β-распада ядер и нейтрона. Показано, что измерение относительных характеристик позволяет избавиться от плохо изученной ядерной структуры, а также представлена возможность определения величины массы антинейтрино (нейтрино) в процессах β-распада с помощью измерения поляризаций и асимметрий. Анализ производился на основе теоретических формул для дифференциальных вероятностей процессов распада. В результате удалось получить формулу для теоретической оценки величины массы антинейтрино
Influence of the magnetic interactions on the mass spectrum of elementary particles
Different approaches to the problem of mass quantization are discussed. The Barut ideas of crucial influence of magnetic forces for explaining the properties of the strong interaction are considered in details. It is shown that this approach gives the possibility to understand the enormous number of elementary particles (about 400) as the excited states of stable fundamental particles (e, p, v), bounded by magnetic interactions. © Published under licence by IOP Publishing Ltd
Massive seminal vesicle cyst with ipsilateral renal agenesis – Zinner syndrome in a Saudi patient
Emergency medicine research in the Philippines: A scoping review
Abstract Objectives In this review, we aim to synthesize the current emergency medicine literature in the Philippines in order to determine the depth of research available in the country while delineating the gaps, helping to provide focus to future research in the field. Methods A literature review was done using 4 databases to identify emergency medicine studies in the Philippines. To explore the research trends among eligible studies, data on study type, countries, and institutions involved as well as study themes were collected and described. Results A total of 845 studies were screened, and 43 were included in this review. Results show that only 25% of emergency medicine studies were published before 2015. Most studies were observational (37.2%) or descriptive (37.2%) in nature with the University of the Philippines/Philippine General Hospital being the most common contributing institution (17.4%). Metro Manila was the most common study site with more than half of studies conducted in the area. Lastly, among the variety of study disciplines, disaster medicine was the most frequent topic comprising 30.2% of studies reviewed. Conclusions Compared to the global scene, Philippine emergency medicine research still has a long way to go. This study was able to provide a landscape of the current literature and highlight the study trends. Further, the findings here emphasize the need to expand the scope of emergency medicine studies in the country as it is still a young and growing field with studies tending to cluster around just a small number of institutions and regions
Interaction of nuclear HDAC5 with 14-3-3 is modulated by liganded PPARs.
<p>Myocytes deprived of serum for 24 h were stimulated with ET1 (0.1 µM). Subsets of cells were also pre-treated with vehicle or PPAR ligands (troglitazone, 1 µM; fenofibrate, 10 µM; GW501516, 1 µM; 1 h) in the presence and absence of shRNA knockdown of DGKζ. HDAC5 was immunoprecipitated, and interaction between HDAC5 and 14-3-3 was assessed biochemically by immunoblotting. Data are presented as percent of normalized 14-3-3 vs. vehicle-treated controls. ET1 treatment significantly increased binding between HDAC5 and 14-3-3. n = 4. The ability of ET1 to increase HDAC5•14-3-3 interaction was <i>A,</i> abolished by liganded PPARs (n = 6), and <i>B</i>, restored by shRNA knockdown of DGKζ (n = 4). **p<0.01 vs. vehicle-treated controls. ‡p<0.01 vs. ET1-treated cells.</p
Effect of DGKζ knockdown on PPAR-mediated suppression of histone H3 acetylation of hypertrophic genes.
<p>mean ± SEM; n = 3;</p><p>*p<0.05 and *p<0.01 vs control;</p>†<p>p<0.05 & <sup>‡</sup>p<0.01 vs ET1.</p><p>Effect of DGKζ knockdown on PPAR-mediated suppression of histone H3 acetylation of hypertrophic genes.</p
Modulation of nuclear DGKζ by liganded PPARs.
<p>Myocytes deprived of serum for 24 h were stimulated with ET1 (0.1 µM). Subsets of cells were also pre-treated with vehicle, R59022 (DGK inhibitor, 10 µM), or PPAR ligands (troglitazone, 1 µM; fenofibrate, 10 µM; GW501516, 1 µM; 1 h). <i>A,</i> Nuclear DAG levels were assessed by ELISA of myocyte nuclear isolates. As would be expected as an output of GPCR-signaling, ET1 increased nuclear DAG levels. Likewise, inhibition of DGK using R59022 (i.e. inhibition of phosphorylative conversion of DAG to phosphatidic acid) also led to augmented nuclear DAG concentrations. n = 4–6. To determine how ET1 might be modulating nuclear DAG concentrations, nuclear DGKζ protein was assessed by <i>B,</i> western blotting of nuclear extracts and total lysates, and <i>C</i>, immunostaining and is presented as percent of normalized DGKζ protein vs. vehicle-treated controls. The ability of ET1 to reduce nuclear DGKζ was abolished by liganded PPARs. n = 4. *p<0.05 and **p<0.01 vs. vehicle-treated controls. †p<0.05 and ‡p<0.01 vs. ET1-treated cells.</p
Liganded PPARs inhibit ET1-dependent activation of nuclear PKCε via DGKζ
<p>. Myocytes deprived of serum for 24 h were stimulated with ET1 (0.1 µM). Subsets of cells were also pre-treated with vehicle or PPAR (troglitazone, 1 µM; fenofibrate, 10 µM; GW501516, 1 µM; 1 h). Activity of PKCε immunoprecipitates was assessed using a commercially-available ELISA-based PKC activity assay kit. The ability of PPARs to attenuate ET1-induced PKCε activity in the nucleus was abolished by shRNA knockdown of DGKζ. n = 3. *p<0.05 and **p<0.01 vs. vehicle-treated controls. ‡p<0.01 vs. ET1-treated cells.</p