610 research outputs found
Towards a Maximal Mass Model
We investigate the possibility to construct a generalization of the Standard
Model, which we call the Maximal Mass Model because it contains a limiting mass
for its fundamental constituents. The parameter is considered as a new
universal physical constant of Nature and therefore is called the fundamental
mass. It is introduced in a purely geometrical way, like the velocity of light
as a maximal velocity in the special relativity. If one chooses the Euclidean
formulation of quantum field theory, the adequate realization of the limiting
mass hypothesis is reduced to the choice of the de Sitter geometry as the
geometry of the 4-momentum space. All fields, defined in de Sitter p-space in
configurational space obey five dimensional Klein-Gordon type equation with
fundamental mass as a mass parameter. The role of dynamical field variables
is played by the Cauchy initial conditions given at , guarantying the
locality and gauge invariance principles. The corresponding to the geometrical
requirements formulation of the theory of scalar, vector and spinor fields is
considered in some detail. On a simple example it is demonstrated that the
spontaneously symmetry breaking mechanism leads to renormalization of the
fundamental mass . A new geometrical concept of the chirality of the fermion
fields is introduced. It would be responsible for new measurable effects at
high energies . Interaction terms of a new type, due to the existence
of the Higgs boson are revealed. The most intriguing prediction of the new
approach is the possible existence of exotic fermions with no analogues in the
SM, which may be candidate for dark matter constituents.Comment: 28 page
Towards a Geometric Approach to the Formulation of the Standard Model
A geometric interpretation of the spontaneous symmetry breaking effect, which
plays a key role in the Standard Model, is developed. The advocated approach is
related to the effective use of the momentum 4-spaces of the constant
curvature, de Sitter and anti de Sitter, in the apparatus of quantum field
theory.Comment: 8 pages, LaTe
Darboux transformation for two component derivative nonlinear Schr\"odinger equation
In this paper, we consider the two component derivative nonlinear
Schr\"{o}dinger equation and present a simple Darboux transformation for it. By
iterating this Darboux transformation, we construct a compact representation
for the soliton solutions.Comment: 12 pages, 2 figure
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Comparison of Time Within Therapeutic Range Using Anti-Factor Xa Versus Activated Partial Thromboplastin Time Monitoring of Unfractionated Heparin in Children.
ObjectiveTo compare unfractionated heparin (UFH) monitoring using time in therapeutic range of activated partial thromboplastin time (aPTT) versus anti-factor Xa activity (anti-Xa) in children.MethodsThis retrospective chart review, with data between October 2015 and October 2019, included pediatric patients younger than 18 years on therapeutic UFH infusion with aPTT or anti-Xa monitoring. Patients receiving extracorporeal membrane oxygenation, dialysis, concomitant anticoagulants, prophylactic UFH, no stated goal, and UFH administered for less than 12 hours were excluded. The primary outcome compared the percentage of time in therapeutic range between aPTT and anti-Xa. Secondary outcomes included time to first therapeutic value, UFH infusion rates, mean rate adjustments, and adverse events.ResultsA total of 65 patients were included, with 33 aPTT patients and 32 anti-Xa patients, representing 39 UFH orders in each group. Baseline characteristics were similar between groups, with an overall mean age of 1.4 years and mean weight of 6.7 kg. The anti-Xa cohort demonstrated a statistically significantly higher percentage of time in therapeutic range compared with the aPTT group (50.3% vs 26.9%, p = 0.002). The anti-Xa group also demonstrated a trend toward decreased time to first therapeutic value compared with aPTT (14 vs 23.2 hours, p = 0.12). Two patients in each group experienced new or worsening thrombosis. Six patients in the aPTT cohort experienced bleeding.ConclusionsThis study demonstrated greater time was spent within therapeutic range for children receiving UFH monitored with anti-Xa compared with aPTT. Future studies should assess clinical outcomes in a larger population
Modern methods of Ta₂O₅ coatings deposition for biomedical applications
The study of e-beam evaporated Ta₂O₅ film structure and properties effect on cell/material response was performed.
The surface properties and structure of e-beam evaporated Ta₂O₅ films were investigated by means of XPS and XRD
methods. The cytotoxicity and cytocompatibility were estimated by in vitro tests. Films of Ta₂O₅ are bio- and
chemically inert, which allows their use in various medical applications, e.g., in diagnostic and treatment techniques
employing short-range quasi-static electric fields for stimulation of positive biological processes in live organisms.Дослідження структури та властивостей покриттiв Ta₂O₅, які нанесено методом електронно-променевого
випарювання, було зроблено методами рентгеноструктурного аналізу та фотоелектронної спектроскопії.
Цитотоксичнiсть i цiтосумiснiсть були визначені in vitro. Плiвки Ta₂O₅ мають бiо- та хімічно- інертні
властивості, що сприятиме їх застосуванню з метою діагностики та лікування з використанням близькодіючих
квазiстацiонарних електричних полів, якi стимулюють позитивні біологічні процеси.Исследования структуры и свойств покрытий Ta₂O₅, нанесенных методом электронно-лучевого испарения,
были проведены методами рентгеноструктурного анализа и фотоэлектронной спектроскопии. Цитотоксичность
и цитосовместимость были определены in vitro. Пленки Ta₂O₅ являются био- и химически- инертными, возможно их применение для диагностики и лечения с использованием близкодействующих квазистационарных электрических полей, стимулирующих позитивные биологические процессы
Impact of baseline anemia on the short- and long-term prognosis of patients presenting with non-st-elevation myocardial infraction (NSTEMI)
Anaemia at admission is a known predictor of death in patients with myocardial infarction with ST-elevation (STEMI). Data on the effect of anaemia on the prognosis in patients with non-ST-elevation myocardial infarction (NSTEMI) is less readily available. Purpose: We aimed to evaluate the frequency of anaemia in a Bulgarian tertiary centre NSTEMI patient population, and its effect on the immediate and extended prognosis of the patients. Methods: We performed ambispective analysis of 138 consecutive patients with NSTEMI, and anaemia was defi ned as haemoglobin at admission below 120 g/L for females and below 130 g/L for males. Results: There was no signifi cant difference in the frequencies of standard risk factors between patients with and without anaemia. Anaemic patients tended to be older, with lower body mass index and worse kidney function. Patients with baseline anaemia tended to have higher GRACE risk scores and a larger size of the realised myocardial infarction as judged by maximal reached troponin I. There was no signifi cant difference in interventional treatment in both groups. Median hospital stay was signifi cantly longer in anaemic patients and was marked by more complications. Despite a lack of increase in inhospital bleeding and no difference in treatment with oral antiaggregants, patients with anaemia received haemotransfusion treatment more often. Mortality rate was higher in anaemic patients both during the index hospitalization and during the follow up. Conclusion: Anaemia at admission is associated with an increased risk of both in hospital cardiovascular complications and after dehospitalisation all-cause mortality in patients with NSTEMI and should be considered as an additional risk factor in the global risk assessment of patients
Estimation of errors in text and data processing
The company Adiss Lab Lts. obtained 1 000 000 medical reports that are either in free form text, or in XML format. One of the main goals of their development is to integrate an algorithm for information extraction (IE) in their platform. The verification of the algorithm’s output for a report is done by a medical doctor (MD) for a certain fee. Validating the correctness of all data would be overwhelming and very expensive. Hence, the problem, as presented by the company, is to provide a method (algorithm) which determines the minimum amount of reports that will validate the correctness of the IE algorithm and a procedure for selecting these reports.
In order to solve the problem we have considered an algorithm-centric approach uses active learning and semi-supervised learning
Recoilless resonant neutrino capture and basics of neutrino oscillations
It is shown that the experiment on recoilless resonant emission and
absorption of , proposed recently by Raghavan, could have an
important impact on our understanding of the physics of neutrino oscillations.Comment: Additional information in the last chapte
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