167 research outputs found
Zeta Nonlocal Scalar Fields
We consider some nonlocal and nonpolynomial scalar field models originated
from p-adic string theory. Infinite number of spacetime derivatives is
determined by the operator valued Riemann zeta function through d'Alembertian
in its argument. Construction of the corresponding Lagrangians L starts
with the exact Lagrangian for effective field of p-adic tachyon
string, which is generalized replacing p by arbitrary natural number n and then
taken a sum of over all n. The corresponding new objects we
call zeta scalar strings. Some basic classical field properties of these fields
are obtained and presented in this paper. In particular, some solutions of the
equations of motion and their tachyon spectra are studied. Field theory with
Riemann zeta function dynamics is interesting in its own right as well.Comment: 13 pages, submitted to Theoretical and Mathematical Physic
Role of the Nuclear and Electromagnetic Interactions in the Coherent Dissociation of the Relativistic Li Nucleus into the H + He Channel
The differential cross section in the transverse momentum and a total
cross section of mb for the coherent dissociation of a 3-A-GeV/
Li nucleus through the HHe channel have been measured on emulsion
nuclei. The observed dependence of the cross section is explained by the
predominant supposition of the nuclear diffraction patterns on light (C, N, O)
and heavy (Br, Ag) emulsion nuclei. The contributions to the cross section from
nuclear diffraction ( MeV/) and Coulomb MeV/)
dissociations are calculated to be 40.7 and 4 mb, respectively.Comment: ISSN 0021-3640, Pleiades Publishing, Ltd., 200
Chickens productivity selection affects immune system genes
The quantitative trait loci associated with the immune properties of chickens are of interest from the point of view of obtaining animals resistant to infectious agents using marker-assisted selection. In the process of selecting markers for genomic selection in broiler-type chickens, a non-standard genotype frequency of the RACK1 gene allele (SNP Gga_rs15788101) in the B5 line of broiler-type chicken cross Smena 8 was identified and it was suggested that this gene was involved in selection. Therefore, it was decided to investigate the available polymorphisms in the three genes responsible for the IgY titer (DMA, RACK1 and CD1B). Molecular typing of single nucleotide polymorphisms of three loci revealed an approach to fixation of the unfavorable allele of the DMA gene (SNP Gga_rs15788237), an approach to fixation of the unfavorable allele of the RACK1 gene and the prevalence of the favorable CD1B gene allele (SNP Gga_rs16057130). Analysis of the haplotypes revealed a strong linkage disequilibrium of these genes. This suggests that these genes experience selection pressure. Analysis of the protein-coding sequences of the CD1B and DMA genes of various breeds of chickens revealed a negative selection of these genes. In order to understand whether the fixation of the studied alleles is the result of artificial selection of the B5 line of the cross Smena 8, an analysis of similar loci in layer chickens Hisex White was carried out. The frequencies of the alleles at the loci of the CD1B gene (Gga_rs16057130) and the RACK1 gene (Gga_rs15788101) in the Hisex White chicken genome differ from the frequencies of the alleles obtained for chickens of the B5 line of the cross Smena 8. It can be assumed that the fixation of the allele in the DMA gene (SNP Gga_rs15723) is associated with artificial or natural selection, consistent in broilers and layers. Changes in the loci Gga_rs16057130 and Gga_rs15788101 in the B5 line of the Smena 8 chickens are most likely associated with artificial selection of broiler productivity traits, which can subsequently lead to fixation of alleles at these loci. Artificial breeding of chickens leads to degradation of the variability of genes encoding elements of the immune system, which can cause a decrease in resistance to various diseases. The study of the negative impact of selection of economic traits on immunity should provide means to mitigate negative consequences and help find ways to obtain disease-resistant animals
Constraints to Coupling Constants of the Omega- and Sigma-Mesons with Dibaryons
The effect of narrow dibaryon resonances to nuclear matter and structure of
neutron stars is investigated in the mean-field theory (MFT) and in the
relativistic Hartree approximation (RHA). The existence of massive neutron
stars imposes constraints to the coupling constants of the omega- and
sigma-mesons with dibaryons. We conclude that the experimental candidates to
dibaryons d1(1920) and d'(2060) if exist form in nuclear matter a Bose
condensate stable against compression. This proves stability of the ground
state for nuclear matter with a Bose condensate of the light dibaryons.Comment: 10 pages, 6 figure
ПОСЛЕОПЕРАЦИОННЫЕ ОСЛОЖНЕНИЯ МАЛОИНВАЗИВНЫХ МЕТОДОВ ЛЕЧЕНИЯ РАКА ПРЕДСТАТЕЛЬНОЙ ЖЕЛЕЗЫ
Prostate cancer is the most common cancer among men. Radical prostatectomy (open, laparoscopic, or robotic) remains the main method of surgical treatment for prostate cancer. However, minimally invasive therapies for prostate cancer are becoming increasingly popular in recent years, because they have similar efficacy as open surgery. The most studied minimally invasive therapies are cryoablation, high intensity focused ultrasound (HIFU), and brachytherapy.Despite the minimization of damage to neighboring structures, minimally invasive procedures can cause a number of complications, like any other surgical interventions. Each method has specific limitations and the most typical complications. Since multiple minimally invasive methods are currently available, we can ensure an individual approach to each particular patient, thus using the advantages of the methods and avoiding possible complications. This article covers the most frequent and severe complications of minimally invasive therapies for prostate cancer, as well as the methods of their prevention and treatment.Рак предстательной железы (РПЖ) является наиболее распространенным онкологическим заболеванием среди мужчин. Радикальная простатэктомия (открытая, лапароскопическая, роботическая) считается основным хирургическим методом лечения РПЖ. Однако в последние годы все бόльшую популярность набирают малоинвазивные методы лечения РПЖ, которые не отстают по эффективности от радикальной операции (по данным последних исследований). К наиболее изученным малоинвазивным технологиям относятся криоаблация, HIFU-терапия (High Intensity Focused Ultrasound) и брахитерапия.Несмотря на минимизацию повреждения соседних структур, малоинвазивные методы лечения РПЖ, как и любые другие хирургические вмешательства, могут приводить к развитию ряда осложнений. Для каждого из методов существуют определенные ограничения, а также наиболее характерные и вероятные осложнения. Благодаря существованию на сегодняшний день целого ряда малоинвазивных методов лечения РПЖ возможен индивидуальный подход к конкретному пациенту, что позволяет избежать нежелательных осложнений и использовать сильные стороны каждого из методов. В настоящей работе рассмотрены наиболее частые и тяжелые осложнения, возникающие после малоинвазивного лечения РПЖ, а также методы их профилактики и лечения
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