Investigations of Y<inf>2</inf>SiO<inf>5</inf>: Nd¹⁴³ by ESR method

© 2016 Elsevier B.V.Here we present the investigation of Y2SiO5 monocrystals doped by isotopically pure 143Nd3+(0.025%) impurity by X-ray and electron spin resonance methods. The crystal structure parameters of Y2SiO5 monocrystal and microscopic parameters: g-tensors and hyperfine structure parameters of two nonequivalent Nd3+ paramagnetic centers were determined

Investigations of Y<inf>2</inf>SiO<inf>5</inf>: Nd¹⁴³ by ESR method

© 2016 Elsevier B.V.Here we present the investigation of Y2SiO5 monocrystals doped by isotopically pure 143Nd3+(0.025%) impurity by X-ray and electron spin resonance methods. The crystal structure parameters of Y2SiO5 monocrystal and microscopic parameters: g-tensors and hyperfine structure parameters of two nonequivalent Nd3+ paramagnetic centers were determined

EPR Detection of Iron Storage in Rat Tissues After Simulated Microgravity Model

© 2016, Springer-Verlag Wien.By a method of spectroscopy of electron paramagnetic resonance the tissues of rats after exposure of microgravity simulation (model of hindlimb unloading) were investigated. In the tissues of heart, lung, liver and muscles the signals of electron magnetic resonance (EMR) depending on orientation were detected. The temperature and orientation dependences of the signals were studied. Comprehensive analysis of the characteristics of the EMR signals made it possible to identify the source of the signals as a crystalline magnetite. Three types of anisotropic EMR signals corresponding to a variety of spatial forms of accumulation of biogenic magnetite were detected. The appearance of the signals after microgravity simulation indicates an alteration in iron metabolism and an abnormal accumulation of iron in the rat tissues

ESR Study of Y<inf>2</inf>SiO<inf>5</inf>:Nd¹⁴³ Isotopically Pure Impurity Crystals for Quantum Memory

© 2017, Springer-Verlag Wien.Two Y2SiO5 single crystals doped with 0.001 at.% of the 143Nd3+ ion (sample I containing the only 28Si isotope) and (sample II with the natural abundance of silicon isotopes) were studied using magnetic resonance methods. The spin–spin and spin–lattice relaxation times were measured at 9.7 GHz between 4 and 10 K. It is established that three relaxation processes describe temperature dependences of the spin–lattice relaxation for both crystals. They are one-phonon, two-phonon Raman and two-phonon Orbach–Aminov relaxation processes. It is established that temperature dependence of spin–spin relaxation time differs for different hyperfine components of the electron paramagnetic resonance spectrum of neodymium ions and depends on the kind of the neodymium isotope (143Nd or 145Nd)

Interplay of rare-earth and transition-metal subsystems in Cu<inf>3</inf>Yb(SeO<inf>3</inf>)<inf>2</inf>O<inf>2</inf>Cl

©2017 American Physical Society We present the synthesis and the experimental and theoretical study of the new member of the francisite family, Cu 3 Yb(SeO 3 ) 2 O 2 Cl. The compound reaches an antiferromagnetic order at T N = 36.7 K and experiences first-order spin-reorientation transition to weakly ferromagnetic phase at T R = 8.7 K evidenced in specific heat C p and magnetic susceptibility χ measurements. Distinctly different magnetization loops in T < T R and T R < T < T N temperature ranges reflect the interplay of rare-earth and transition-metal subsystems. At low temperatures, the saturation magnetization M s ∼ 5.2 μ B is reached in pulsed magnetic-field measurements. The electron spin resonance data reveal the complicated character of the absorption line attributed to response from both copper and ytterbium ions. Critical broadening of the linewidth at the phase transitions points to quasi-two-dimensional character of the magnetic correlations. The spectroscopy of Yb 3+ ions evidences splitting of the lowest-energy Kramers doublet of 2 F 5 / 2 excited multiplet at T R < T < T N while the ground Kramers doublet splits only at T < T R . We describe the magnetic properties both above and below the spin-reorientation transition in the framework of a unified approach based on the mean-field approximation and crystal-field calculations

Современные данные о патогенезе и лечении гипоксически-ишемических поражений головного мозга у новорожденных

Hypoxic-ischemic brain lesions in children are the main environmental (non-genetic) factor in forming severe neurological pathology with subsequent disability. Scientists see the improvement of therapeutic approaches in acute phase of the disease as a main way to reduce the severity of neurologic complications. Due to the achievements in neuroscience in the field of perinatal hypoxicischemic injury mechanisms, three energy phases of pathologic events deployment were identified: primary (up to 6 hours from the lesion), secondary (6 to 24–48 h after the lesion) and distal tertiary (during few weeks, months). At the same time, necrosis, apoptosis, glutamate excitotoxicity, oxidative stress, inflammation, angiogenesis and neurogenesis make up separate links of destruction process. On the basis of new data on the pathogenesis of the disease, scientists from different countries have already offered modern treatment methods for perinatal hypoxic-ischemic injury with erythropoietin, allopurinol, melatonin, N-acetylcysteine, magnesium sulphate, albumin, -interferon, as well as with the help of controlled hypothermia, xenon, the use of stem cells, etc. This article presents a review of new data on pathogenesis and promising treatment methods for perinatal hypoxic-ischemic injuries.Гипоксически-ишемические поражения головного мозга у детей являются главным средовым (негенетическим) фактором формирования у них тяжелой неврологической патологии с последующей инвалидизацией. В качестве основного пути снижения тяжести неврологических осложнений ученые видят совершенствование лечебных подходов в острый период заболевания. Благодаря достижениям нейронауки в области изучения механизмов гипоксически-ишемических перинатальных повреждений (ГИПП) были определены три энергетические фазы развертывания патологических событий: первичная (до 6 ч с момента поражения), вторичная (от 6 до 24–48 ч от момента поражения) и отдаленная третичная (в течение нескольких недель-месяцев). При этом некроз, апоптоз, глутаматная эксайтотоксичность, окислительный стресс, воспаление, ангио- и нейрогенез составляют отдельные звенья процесса поражения. На основании новых данных о патогенезе заболевания ученые разных стран уже предложили современные методы лечения ГИПП препаратами эритропоэтина, аллопуринола, мелатонина, N-ацетилцистеина, сульфата магния, альбумина, -интерферона, а также при помощи управляемой гипотермии, ксенона, использования стволовых клеток и др. В статье представлен обзор новых данных о патогенезе и перспективных методах лечения ГИПП

Exchange interactions in Cu<inf>2</inf>AlBO<inf>5</inf> and Cu<inf>2</inf>GaBO<inf>5</inf>

© 2020 Author(s). Single crystals of ludwigite Cu2MeBO5 (Me=Al, Ga) were synthesized by flux growth technique. The calculations of the exchange integrals in frameworks of indirect coupling model revealed that monoclinic distortions strongly affect exchange interactions. We have performed electron spin resonance (ESR) measurements for untwined single crystals of Cu2MeBO5 (Me=Al, Ga). The observed anisotropy of the ESR linewidth result from the one-dimensional chain like structure of Cu2MeBO5 (Me=Al, Ga) and the anisotropic exchange interactions between Cu ions, respectively

Clinical, Morphological, and Immunohistochemical Justification of Surgery for Chronic Appendicitis in Children

Objective: Chronic appendicitis (CA) is a diagnosis characterized by long-standing right lower quadrant pain. We analyzed clinical, morphological, and immunohistochemical studies of the appendix to confirm the adequacy of surgery for CA in children with chronic right lower quadrant pain. Patients and Methods: We carried out comparative studies of clinical presentations and results of morphological and immunohistochemical studies of remote appendicitis in 55 children with chronic recurrent lower quadrant pain (CRLQP). Results: Morphological and immunohistochemical studies revealed three types of changes in the appendix. Type 1 (n = 21) - chronic inflammation. Inflammatory leukocyte infiltration was localized within the mucous membrane of the appendix. An immunohistochemical study revealed a significant (P < .01) increase in the expression of CD106 (vascular cell adhesion molecule 1) and in the number of matrix metalloproteinase 9 (MMP-9) positive cells. Type 2 (n = 20) - lymphoid hyperplasia. Morphological changes were characterized by lymphoid infiltration of the mucosa and submucosa of the appendix. Immunological changes were characterized by an increase (P < .01) in the expression and number of MMP-9, expression of CD106 positive cells, an increase in the expression of collagen IIIα in combination with a decrease in the expression and number of positive vascular endothelial growth factor (VEGF) and vasoactive intestinal peptide cells. Type 3 (n = 12) - catarrhal inflammation. Morphological changes were characterized by impaired blood circulation only in the mucous membrane, without destructive or inflammatory changes. Immunological changes were characterized by an increase (P < .01) in the expression and number of VEGF-positive cells, which may indicate a response to local hypoxia of the appendix and explain neovascularization in a chronic condition. The abdominal syndrome after appendectomy was noted to disappear in 89% of patients. The established changes in remote appendicitis, other than acute inflammation, make it possible to consider reasonable appendectomy a way of treating CRLQP in children. Conclusions: We have identified immunohistochemical and morphological changes pointing to autoimmune and vascular mechanisms of appendix damage in children with CRLQP. Laparoscopic appendectomy helps to eliminate abdominal pain in most CA patients. © Copyright 2021, Mary Ann Liebert, Inc., publishers 2021

КОНЦЕПЦИЯ СОХРАНЕНИЯ И НЕИСТОЩИМОГО ИСПОЛЬЗОВАНИЯ ЛЕСНЫХ ГЕНЕТИЧЕСКИХ РЕСУРСОВ В УКРАИНЕ

Elaboration and adoption of the "Concept for the conservation and sustainable use of forest genetic resources in Ukraine" were caused by the need to define the strategic goals and objectives, methodological, methodical, organizational principles and techniques for conservation of forest genetic resources in Ukraine on a nationwide scale. The development of the Concept aims at providing stable functioning of forest ecosystems today and in the future, preserving the potential of forests for producing of their unique set of economic, environmental and social benefits. The use of the document will serve as the basis for developing of new and improving the existing legislative, departmental and administrative regulations that provide different aspects of biodiversity conservation in forests – programs, regulations, guidelines, directives, recommendations, etc. In the Concept, which is developed in Ukraine for the first time, characterized are the topicality and the necessity for conservation of forest genetic resources, the classification of factors that endanger the genetic diversity of forest tree species is described, legal basis of the process for conserving forest genetic resources is analyzed, the methods and strategy of genetic variability of forest tree species conservation are reported, attention was paid to the benefits from sustainable use of forest genetic resources, also here were indicated the necessity of scientific support of this process and outlined ways of implementing this concept.Розроблення й прийняття Концепції зумовлена потребою розробки методів збереження та невиснажливого використання лісових генетичних ресурсів в Україні, визначення стратегічної мети й завдань, методологічних, методичних, організаційних принципів і прийомів діяльності зі збереження генетичної мінливості лісів. Вона покликана забезпечити стабільність функціонування лісових екосистем сьогодні та в майбутньому, зберегти потенціал лісів стосовно продукування ними комплексу унікальних економічних, екологічних й соціальних благ. Використання документу слугуватиме основою для розробки нових й удосконалення існуючих законодавчо-правових, нормативно-регулюючих і організаційно-розпорядчих актів, що забезпечують різні сторони збереження біорізноманіття в лісах – програм, положень, настанов, вказівок, інструкцій, рекомендацій тощо. У Концепції охарактеризована актуальність й необхідність збереження лісових генетичних ресурсів, приведена класифікація загроз зниження генетичного різноманіття лісових деревних порід, проаналізовані правові засади процесу збереження лісових генетичних ресурсів, розроблені методи й стратегії збереження генетичної мінливості лісових деревних видів, приділена увага сталому користуванню вигодами від збереження лісових генетичних ресурсів, вказано на науковий супровід цього процесу і віднайдено шляхи реалізації даної Концепції, яка в Україні розроблена вперше.Разработка и утверждение Концепции обусловлено необходимостью разработки методов сохранения и неистощимого использования лесных генетических ресурсов в Украине, определения стратегической цели и задач, методологических, методических, организационных принципов и приемов деятельности по сохранению генетической изменчивости лесов. Она предназначена обеспечить стабильность функционирования лесных экосистем сегодня и в будущем, сохранить потенциал лесов в сфере продуцирования ими комплекса уникальных экономических, экологических и социальных благ. Использование документа будет служить основой для разработки новых и усовершенствования существующих законодательно-правовых, нормативно-регулирующих и организационно-распорядительных актов, обеспечивающих различные стороны сохранения биоразнообразия в лесах – программ, положений, наставлений, указаний, инструкций, рекомендаций и т.п. В Концепции охарактеризована актуальность и необходимость сохранения лесных генетических ресурсов, приведена квалификация угроз снижения генетического разнообразия лесных древесных пород, проанализированы правовые основы процесса ее сохранности, разработаны методы и стратегии сбережения генетической изменчивости лесных древесных пород, уделено внимание постоянному использованию преимуществ от сохранения лесных генетических ресурсов, обращено внимание на научное сопровождение этого процесса и найдены пути реализации данной Концепции, которая в Украине разработана впервые