Charge Radii and Magnetic Polarizabilities of the Rho and K* Mesons in QCD String Theory

The effective action for light mesons in the external uniform static electromagnetic fields was obtained on the basis of QCD string theory. We imply that in the presence of light quarks the area law of the Wilson loop integral is valid. The approximation of the Nambu-Goto straight-line string is used to simplify the problem. The Coulomb-like short-range contribution which goes from one-gluon exchange is also neglected. We do not take into account spin-orbital and spin-spin interactions of quarks and observe the $\rho$ and $K^*$ mesons. The wave function of the meson ground state is the Airy function. Using the virial theorem we estimate the mean charge radii of mesons in terms of the string tension and the Airy function zero. On the basis of the perturbative theory, in the small external magnetic field we find the diamagnetic polarizabilities of $\rho$ and $K^*$ mesons: $\beta_\rho =-0.8\times 10^{-4} {fm}^3$, $\beta_{K^*}=-0.57\times 10^{-4} {fm}^3$Comment: 22 pages, no figures, in LaTeX 2.09, typos correcte

Square vortex solitons with a large angular momentum

We show the existence of square shaped optical vortices with a large value of the angular momentum hosted in finite size laser beams which propagate in nonlinear media with a cubic-quintic nonlinearity. The light profiles take the form of rings with sharp boundaries and variable sizes depending on the power carried. Our stability analysis shows that these light distributions remain stable when propagate, probably for unlimited values of the angular momentum, provided the hosting beam is wide enough. This happens if the peak amplitude approaches a critical value which only depends on the nonlinear refractive index of the material. A variational approach allows us to calculate the main parameters involved. Our results add extra support to the concept of surface tension of light beams that can be considered as a trace of the existence of a liquid of light.Comment: 6 pages, 6 figures, submitted to Phys. Rev.

Different-sized porosity and thermal conductivity of oxide layers formed by plasma-electrolytic oxidation on the AlSi12Mg silumin

Oxide layers formed by plasma-electrolytic oxidation (PEO) are characterized by a sufficiently high porosity, which influences almost the whole complex of service characteristics. However, the known data on the integral porosity of PEO-produced layers are rather contradictory, and the pore size distribution in these layers remains understudied. Pore size distribution in the range of 10 nm to 10 µm (pore geometry was approximated by a spherical shape) was obtained by using analysis of scanning electron microscopy (SEM) images in a wide range of magnifications. Lognormal distribution function fits the shape of pore size distribution sufficiently well. Such distribution indicates the nature of pore formation, which can be related to the thermally activated process of gas emission from a liquid melt, the volume and average temperature of which, in turn, depend on the micro-arc discharge energy. The results of the oxide layer phase composition and crystallites sizes by the X-ray crystallography were described in the present paper. The amorphous component phase composition was estimated by the comparing of the of X-ray spectral microanalysis and X-ray crystallography methods. The thermal conductivity of the intact oxide layer and the polished layer (after the removal of its highly-porous outer part) was evaluated by using of the steady-state method and the laser flash method. The porosity values calculated based on the analysis of SEM-images, and the results of determining the phase composition, including amorphous phases, allowed evaluating the oxide layer thermal conductivity with use of four known analytical models. The results of calculating the thermal conductivity using the Loeb model demonstrate the good convergence with the experimental results obtained in this paper. Modeling results the size of crystallites effect on the oxide layer thermal conductivity significantly less than the porosity and amorphous phase

Giant and tunable excitonic optical anisotropy in single-crystal CsPbX3_3 halide perovskites

During the last years, giant optical anisotropy demonstrated its paramount importance for light manipulation which resulted in numerous applications ranging from subdiffraction light guiding to switchable nanolasers. In spite of recent advances in the field, achieving continuous tunability of optical anisotropy remains an outstanding challenge. Here, we present a solution to the problem through chemical alteration of the ratio of halogen atoms (X = Br or Cl) in single-crystal CsPbX$_3$ halide perovskites. It turns out that the anisotropy originates from an excitonic resonance in the perovskite, which spectral position and strength are determined by the halogens composition. As a result, we manage to continually modify the optical anisotropy by 0.14. We also discover that the halide perovskite can demonstrate optical anisotropy up to 0.6 in the visible range -- the largest value among non-van der Waals materials. Moreover, our results reveal that this anisotropy could be in-plane and out-of-plane, depending on perovskite shape -- rectangular and square. Hence, it can serve as an additional degree of freedom for anisotropy manipulation. As a practical demonstration, we created perovskite anisotropic nanowaveguides and show a significant impact of anisotropy on high-order guiding modes. These findings pave the way for halide perovskites as a next-generation platform for tunable anisotropic photonics.Comment: 18 pages, 3 figure

Neutron-induced astrophysical reaction rates for translead nuclei

Neutron-induced reaction rates, including fission, are calculated in the temperature range 1.d8 <T (K) < 1.d10 within the framework of the statistical model for targets with atomic number 83 < Z < 119 (from Po to Uuo) from the neutron to the proton drip-line. Four sets of rates have been calculated, utilizing - where possible - consistent nuclear data for neutron separation energies and fission barriers from Thomas-Fermi (TF), Extended Thomas-Fermi plus Strutinsky Integral (ETFSI), Finite-Range Droplet Model (FRDM) and Hartree-Fock-Bogolyubov (HFB) predictions. Tables of calculated values as well as analytic seven parameter fits in the standard REACLIB format are supplied. We also discuss the sensitivity of the rates to the input, aiming at a better understanding of the uncertainties introduced by the nuclear input.Comment: 14 pages, 10 figures, 2 tables in paper, 2 in Annex and online tables example

Theory and Applications of X-ray Standing Waves in Real Crystals

Theoretical aspects of x-ray standing wave method for investigation of the real structure of crystals are considered in this review paper. Starting from the general approach of the secondary radiation yield from deformed crystals this theory is applied to different concreat cases. Various models of deformed crystals like: bicrystal model, multilayer model, crystals with extended deformation field are considered in detailes. Peculiarities of x-ray standing wave behavior in different scattering geometries (Bragg, Laue) are analysed in detailes. New possibilities to solve the phase problem with x-ray standing wave method are discussed in the review. General theoretical approaches are illustrated with a big number of experimental results.Comment: 101 pages, 43 figures, 3 table

Внедрение лапароскопических технологий в хирургию колоректального рака на примере регионального онкологического центра

Objective: to evaluate complication rate, surgical operation time, mortality rate implementing minimally invasive surgical technique in colon and rectal surgery — a single cancer’s center experience.Matherials and methods. 124 patients underwent surgery in the period from 2016 to 2018 using laparoscopic technique for colorectal cancer. All patients were divided on 3 equal groups, depending on the time required to master laparoscopic technique: group A (1—40 procedure), group B (41—80 procedure) and group C (81—124 procedure). Outcome measures included operation time, mortality rate, readmission and postoperative complication rates, number of lymph nodes removed and time of impatient care.Results. Main outcome variables (operation time, number lymph nodes removed, time of impatient care, mortality rates, postoperative complication rates) reach a plateau in the learning curve after 54 operation. The study showed that the incidence of postoperative complications in all groups was 11.4 %, while the significantly high level of complications was in group A — 17.5 % (p = 0.023). Postoperative mortality in groups A and B was 2.5 % and 2.5 %, respectively.Conclusion. It is shown that the introduction of minimally invasive technologies into colorectal cancer surgery is relatively safe and possible under the given conditions, while the time of mastering the technique is comparable with the data available in the literature.Цель исследования — оценить частоту осложнений, время операции и летальность при внедрении минимально инвазивных хирургических технологий в хирургию колоректального рака на примере регионального онкологического центра.Материалы и методы. Проведен ретроспективный анализ 124 пациентов, оперированных минимально инвазивным доступом по поводу колоректального рака. В зависимости от времени освоения хирургической технологии все пациенты были разделены на 3 группы: А (операции с 1-й по 40-ю), В (с 41-й по 80-ю) и С (с 81-й по 124-ю). Анализировали следующие параметры: количество удаленных лимфатических узлов, частоту осложнений, летальность и продолжительность пребывания пациента в стационаре. Результаты. Достижение уровня плато основных анализируемых показателей наступило после 54-го вмешательства. Как показало исследование, частота послеоперационных осложнений во всех группах составила 11,4 %, при этом достоверно высокий уровень осложнений был в группе A — 17,5 % (p = 0,023). Послеоперационная летальность имела место в группах A и B — 2,5 и 2,5 % соответственно.Выводы. Внедрение минимально инвазивных технологий в хирургию колоректального рака относительно безопасно и возможно в условиях регионального онкологического стационара. Кривая обучения в региональной больнице сопоставима с данными, представленными в источниках литературы

Эмоциональные и личностные особенности восприятия боли у женщин при эндометриозе

Introduction. This article is devoted to psychological features in patients with pain syndrome in endometriosis and their pain perception.The objective of the study was to identify features of pain syndrome perception, personality traits, emotional features and satisfaction with quality of life in patients with endometriosis.Material and methods. 56 women were examined: 27 patients with endometriosis and 29 women without gynecological diseases. The following psychodiagnostic methods were used: «The McGill Pain Questionnaire», «Visual Analogue Scale», «Giessen test», the test of L. N. Sobchik «Diagnosis of interpersonal relationships», the questionnaire of N. E. Vodopyanova «Assessment of the level of satisfaction with the quality of life», «Hospital Anxiety and Depression Scale» (HADS).Results. The results of the study indicated that patients with painful forms of endometriosis were less satisfied with the quality of life in the field of health, emotional and physical comfort. The feminine type of gender-role behavior was identified in self-perception, and the responsibly-magnanimous style prevails in interpersonal relations. The perception of pain was interrelated with interpersonal behavior style.Conclusion. Psychological characteristics of patients with endometriosis must have been taken into account during treatment and rehabilitation, since they affected the subjective perception of pain, could reduce satisfaction with the quality of life and worsen the emotional state.Введение. Рассматриваются психологические особенности пациенток с болевым синдромом при эндометриозе, а также их связь с восприятием боли.Цель исследования – выявление особенностей восприятия болевого синдрома, а также личностных, эмоциональных особенностей и удовлетворенности качеством жизни у женщин с эндометриозом.Материал и методы. Всего обследованы 56 испытуемых: 27 женщин с эндометриозом и 29 женщин без гинекологической патологии. Использованные психодиагностические методики: Болевой опросник Мак-Гилла, визуальная аналоговая шкала боли, «Оценка уровня удовлетворенности качеством жизни» (в адаптации Н. Е. Водопьяновой), «Гиссенский личностный опросник», Метод диагностики межличностных отношений (ДМО Л. Н. Собчик), Госпитальная шкала тревоги и депрессии (HADS).Результаты. В результате исследования было выявлено, что для пациенток с болевой формой эндометриоза характерна меньшая удовлетворенность качеством жизни в сфере здоровья, эмоционального и физического комфорта. В восприятии себя наблюдается феминный тип поло-ролевого поведения, а в межличностных отношениях преобладает ответственно-великодушный стиль. Восприятие боли взаимосвязано со стилем поведения в межличностных отношениях.Выводы. При лечении и реабилитации пациенток с эндометриозом необходимо учитывать их психологические особенности, поскольку они оказывают влияние на субъективное восприятие болевого синдрома, могут снижать удовлетворенность качеством жизни и ухудшать эмоциональное состояние

Сравнительная характеристика различных способов изолированной химиоперфузии печени

Background. Metastatic liver injury is a  distinct oncological problem, irrespective of primary malignancy. Resection surgery is not always feasible in such patients. Isolated liver chemoperfusion is a promising treatment option in multiple small-focal metastatic organic lesions. This technique is technically complex, which limits its broader evaluation and adoption in clinical practice. The diversity of isolated liver chemoperfusion techniques does not allow an adequate assessment of world experience and requires further research. The important considerations with introducing isolated liver chemoperfusion are: an optimal surgical technique, liver isolation control method, as well as physiological arterial and portal blood flow maintenance.Materials and methods. A total of 21 patients were surveyed over June 2020 — December 2021. The patients were divided into 3 prospective cohorts: A) arteriocaval chemoperfusion, midline laparotomy access, technical-guided liver isolation, B) arteriocaval chemoperfusion, “in J laparotomy” access, ICG-guided liver isolation, C) arterio-porto-caval chemoperfusion, “in J laparotomy” access, ICG-guided liver isolation. A procedure’s tolerance was assessed with: the duration of surgery, postoperative ICU bed-days, total postoperative bed-days, hepatic cytolysis rates, chemotherapy side-effects severity.Results and discussion. The duration of surgery shortened with “in J laparotomy”. Haemotoxicity did not differ between cohorts A and B, albeit appearing significantly lower in cohort C. The cytolytic syndrome duration statistically significantly reduced in C vs. A and B cohorts.Conclusion. All the isolated liver chemoperfusion techniques employed are patient-safe. In ICG-guided liver isolation, the agent leakage into systemic blood flow is less likely, indicating a lower haemotoxicity. Arterioportal isolated chemoperfusion is more physiological compared to other techniques, thus facilitating lower hepatotoxicity. The use of “in J laparotomy” significantly reduces liver mobilisation and vascular cannulation times. Введение. Метастатическое поражение печени является отдельной проблемой онкологии независимо от первичного злокачественного заболевания. Резекционная хирургия не всегда осуществима у таких пациентов. При множественном мелкоочаговом метастатическом поражении органа многообещающим является лечение методом изолированной химиоперфузии печени. Эта методика технически сложна, что ограничивает её изучение и внедрение в широкую клиническую практику. Разнообразие способов проведения изолированной химиоперфузии печени не позволяет однозначно оценивать накопленный мировой опыт и требует дальнейшего изучения. В процессе внедрения изолированной химиоперфузии печени важными вопросами являются: оптимальная хирургическая техника, способ контроля изоляции печени, поддержание физиологичного артериального и портального кровотока.Материалы и методы. В исследовании принял участие 21 пациент в период с июня 2020 по декабрь 2021 г. Пациенты разделены на 3 проспективные группы: A) артерио-кавальная химиоперфузия печени, доступ через срединную лапаротомию, технический контроль полноты изоляции печени, B) артерио-кавальная химиоперфузия печени, доступ через J-лапаротомию, ICG-контроль полноты изоляции печени, C) артерио-порто-кавальная химиоперфузия печени, доступ через J-лапаротомию, ICG-контроль полноты изоляции печени. С целью оценки переносимости процедуры оценивались: длительность операции. послеоперационный койко-день в  отделении интенсивной терапии, общий послеоперационный койко-день, показатели печеночного цитолиза, выраженность побочных эффектов химиопрепарата.Результаты и обсуждение. Длительность операции сократилась с применением J-лапаротомии. Выраженность гематологической токсичности не различалась между группами A и B, однако значительно ниже в группе С. Длительность цитолитического синдрома статистически значимо снизилась в группе C при сравнении с группами A и B.Заключение. Все примененные нами способы изолированной химиоперфузии печени безопасны для пациента. При контроле изоляции печени с применением ICG снижается вероятность утечки химиопрепарата в системный кровоток, что показывает меньшую гематологическую токсичность. Проведение артерио-портальной изолированной химиоперфузии физиологичнее других примененных способов и способствует снижению гепатотоксичности. Применение J-лапаротомии значительно сокращает время мобилизации печени и канюляции сосудов.

Detection of π+π−\pi^+\pi^-atoms with the DIRAC spectrometer at CERN

The goal of the DIRAC experiment at CERN is to measure with high precision the lifetime of the $\pi^+\pi^-$ atom ($A_{2\pi}$), which is of order $3\times10^{-15}$ s, and thus to determine the s-wave $\pi\pi$-scattering lengths difference $|a_{0}-a_{2}|$. $A_{2\pi}$ atoms are detected through the characteristic features of $\pi^+\pi^-$ pairs from the atom break-up (ionization) in the target. We report on a first high statistics atomic data sample obtained from p Ni interactions at 24 GeV/$c$ proton momentum and present the methods to separate the signal from the background.Comment: 19 pages, 12 figures, 1 tabl