179 research outputs found
The influence of the microstructure morphology of two phase Ti-6Al-4V alloy on the mechanical properties of diffusion bonded joints
The influence of ultra fine grained (UFG) and coarse grained (CG) microstructure of the titanium alloy Ti-6Al-4V on the strength of a diffusion bonded (DB) joint was studied using a laboratory DB fixture and a new shear test rig. The DB process was carried out at 725°C and 825°C during 2 and 4 hours in a vacuum furnace. Coarsening of grain structure resulting from different DB cycles was quantified. The chain pores were observed at 725°C for both microstructure conditions bonded during 2 hours. The increase of bonding time up to 4 hours leads to subsequent elimination of the pores. The UFG samples bonded at 725°C showed a higher level of the shear strength than CG samples for both bonding times. The CG material demonstrated the highest shear strength after 4 hours of DB bonding at 825°C. The increase of the creep deformation of UFG samples when compared to the CG condition was observed as a result of DB at of 725° C during 4 hours
Special section guest editorial: advances in terahertz biomedical science and applications
The Journal of Biomedical Optics (JBO) has published this special section of papers to capture the most recent advances in THz technology and innovative THz instruments and methods in biology and medicine. A few of the papers in this special section are dedicated to similar biomedical applications of novel optical tools from the neighboring infrared (IR) range. Two papers of the special section consider modern problems of oncodiagnosis. In the research article ‘Development of oral cancer tissue-mimicking phantom based on polyvinyl chloride plastisol and graphite for terahertz frequencies’, authors have introduced a new type of a water-free tissue-mimicking phantom for THz biophotonics. This phantom is based on graphite powders embedded into a polyvinyl chloride plastisol matrix. The effective THz optical properties of such a phantom can be managed in a wide range by changing its composition, thus allowing to mimic the THz optical properties of various biological tissues
Современные аспекты фотодинамической терапии при базальноклеточном раке кожи
Photodynamic therapy (PDT) is one of the most effective treatments for basal cell skin cancer (BCC). As the incidence rate of BCC is increasing worldwide, interest in developing new methods for diagnosing and treating this disease, taking into account long-term cosmetic results, is growing. The review article presents the results of domestic and foreign studies on the treatment of BCC with PDT. The presented results of studies from various domestic and foreign clinics indicate the high efficiency of independent PDT and a combination of PDT with other treatment methods. PDT is proposed to be used in combination with surgical methods and radiation therapy, immunomodulating and chemotherapeutic agents, and inhibitors of molecules involved in the carcinogenic process. These new strategies open the way to increasing the effectiveness of treatment and prevention of BCC. Moreover, in all studies, the safety of this non-invasive treatment, a low level of adverse reactions during therapy, good tolerance for the patient and excellent cosmetic treatment results are noted. The guidelines currently being developed in Europe and the United States provide consistent expert advice that reflects current published evidence of treatment outcomes for BCC using PDT. Moreover, the recommendations emphasize that the treatment plan for patients with “difficult to treat” BCC should be discussed at an interdisciplinary oncological council.Фотодинамическая терапия (ФДТ) является одним из наиболее эффективных методов лечения базальноклеточного рака кожи (БКРК). По мере роста показателей заболеваемости БКРК во всём мире всё больше возрастает интерес к разработке новых методов диагностики и лечения данного заболевания с учётом отдалённых косметических результатов. В обзорной статье приводятся результаты отечественных и зарубежных исследований по лечению БКРК с помощью ФДТ. Представленные результаты исследований различных отечественных и зарубежных клиник свидетельствуют о высокой эффективности самостоятельной ФДТ и комбинации ФДТ с другими методами лечения. ФДТ предлагается применять в сочетании с хирургическими методами и лучевой терапией, иммуномодулирующими и химиотерапевтическими агентами, ингибиторами молекул, участвующих в канцерогенном процессе. Эти новые стратегии открывают путь к повышению эффективности лечения и профилактики БКРК. При этом во всех исследованиях отмечается безопасность данного неинвазивного лечения, низкий уровень побочных реакций при проведении терапии, хорошая переносимость для пациента и превосходные косметические результаты лечения. В разработанных в настоящее время в Европе и США руководствах представлены согласованные экспертные рекомендации, отражающие текущие опубликованные доказательства результативности лечения БКРК с использованием ФДТ. При этом в рекомендациях подчеркивается, что план терапии пациентов с трудно поддающимися лечению БКРК должен обсуждаться на междисциплинарном онкологическом совете
КОНКУРЕНТОСПОСОБНОСТЬ В СРЕДЕ ИННОВАЦИОННОГО ПРЕДПРИНИМАТЕЛЬСТВА
The theme of this article is relevant because in any economic doctrine of competition is seen as a driving force of the market. The ability of business entities, including entities of innovative entrepreneurship to compete for the market (consumers) is a key factor in the development of this segment and the main factor stimulating the transition of the national economy to innovation-oriented development.The purpose: The aim of the article is in-depth and comprehensive analysis of the positions of Russian and foreign scientists-economists on the question of the essence of the concepts of «competition» and «competitiveness».Methods. Methodological basis of this paper are generalization of literary sources and comparative analysis methods. Results. Comprehensively analyzed the positions of leading scientists and economists in relation to the concepts of «competition and competitiveness», including and in such an important sector as innovative entrepreneurship. The identifi ed similarities, diff erences and their features.Conclusions / significance. Identifi ed and completed a substantial part of the economic category «competitiveness of innovative entrepreneurship». According to the authors, the competitiveness of innovative entrepreneurship should be considered as the ability of the subjects of this segment to compete in a superior degree with the manufacturers (sellers) of a similar product (goods, works, services) with the best (unique) characteristics through effi cient and optimal use of knowledge and other resources to support the activities to maximize the economic benefi ts, not available to competitors of, or adjacent segment.В любом экономическом учении конкуренция рассматривается как движущая сила рынка. Способность хозяйствующих субъектов, в том числе и субъектов инновационного предпринимательства конкурировать за рынок (потребителя), является ключевым фактором развития данного сегмента и основным фактором, стимулирующим переход национальной экономики к инновационно ориентированному развитию. Целью статьи является глубокий и всесторонний анализ позиций российских и зарубежных ученых-экономистов по вопросу сущности понятий «конкуренция» и «конкурентоспособность». Методической основой данной статьи являются метод обобщения литературных источников и сравнительные методы анализа.В статье всесторонне проанализированы позиции ведущих ученых-экономистов в отношении понятий «конкуренция» и конкурентоспособность», в том числе и в такой значимой сфере как инновационное предпринимательство. Выявлены сходства, различия и их особенности.Выводы / значимость. Выявлена и дополнена содержательная часть экономической категории «конкурентоспособность инновационного предпринимательства». По мнению авторов, конкурентоспособность инновационного предпринимательства необходимо рассматривать как способность субъектов этого сегмента конкурировать в превосходящей степени с производителями (продавцами) аналогичного продукта (товара, работы, услуги) с лучшими (уникальными) характеристиками, посредством эффективного и оптимального использования знаниевых и прочих ресурсов для обеспечения деятельности, что позволяет максимизировать этим субъектам экономические выгоды, недоступные конкурентам данного или смежного сегмента
Перспективы создания искусственных тканей и органов человека на основе метода трехмерной биопечати
Three-dimensional (3D) printing is a method of creating a material object layer-by-layer in space from a virtual, mathematical model. 3D printing is based on additive technologies – a step-by-step formation of a structure by adding material to the base. 3D bioprinting is the fabrication of functional biological structures that mimic human organs and tissues. Analysis of scientific publications showed that in the near future, viable and fully functional artificial copies of individual human organs and tissues can be obtained.Трехмерная (3D) печать – это процесс послойного создания в пространстве материального объекта из виртуальной, математической модели. Метод 3D-печати основан на аддитивных технологиях – поэтапном формировании конструкции путем добавления материала на основу. 3D-биопечать – создание функциональных биологических структур, которые имитируют органы и ткани человека. Анализ научных публикаций показал, что в недалеком будущем возможно получение жизнеспособных и полноценно функционирующих искусственных копий отдельных органов и тканей человека
Neurodevelopmental Syndrome with Intellectual Disability, Speech Impairment, and Quadrupedia Is Associated with Glutamate Receptor Delta 2 Gene Defect
Bipedalism, speech, and intellect are the most prominent traits that emerged in the evolution of; Homo sapiens; . Here, we describe a novel genetic cause of an "involution" phenotype in four patients, who are characterized by quadrupedal locomotion, intellectual impairment, the absence of speech, small stature, and hirsutism, observed in a consanguineous Brazilian family. Using whole-genome sequencing analysis and homozygous genetic mapping, we identified genes bearing homozygous genetic variants and found a homozygous 36.2 kb deletion in the gene of glutamate receptor delta 2 (; GRID2; ) in the patients, resulting in the lack of a coding region from the fifth to the seventh exons. The; GRID2; gene is highly expressed in the cerebellum cortex from prenatal development to adulthood, specifically in Purkinje neurons. Deletion in this gene leads to the loss of the alpha chain in the extracellular amino-terminal protein domain (ATD), essential in protein folding and transport from the endoplasmic reticulum (ER) to the cell surface. Then, we studied the evolutionary trajectories of the; GRID2; gene. There was no sign of strong selection of the highly conservative; GRID2; gene in ancient hominids (Neanderthals and Denisovans) or modern humans; however, according to in silico tests using the Mfold tool, the; GRID; 2 gene possibly gained human-specific mutations that increased the stability of; GRID2; mRNA
Chromatin profiling of cortical neurons identifies individual epigenetic signatures in schizophrenia
Both heritability and environment contribute to risk for schizophrenia. However, the molecular mechanisms of interactions between genetic and non-genetic factors remain unclear. Epigenetic regulation of neuronal genome may be a presumable mechanism in pathogenesis of schizophrenia. Here, we performed analysis of open chromatin landscape of gene promoters in prefrontal cortical (PFC) neurons from schizophrenic patients. We cataloged cell-type-based epigenetic signals of transcriptional start sites (TSS) marked by histone H3-K4 trimethylation (H3K4me3) across the genome in PFC from multiple schizophrenia subjects and age-matched control individuals. One of the top-ranked chromatin alterations was found in the major histocompatibility (MHC) locus on chromosome 6 highlighting the overlap between genetic and epigenetic risk factors in schizophrenia. The chromosome conformation capture (3C) analysis in human brain cells revealed the architecture of multipoint chromatin interactions between the schizophrenia-associated genetic and epigenetic polymorphic sites and distantly located HLA-DRB5 and BTNL2 genes. In addition, schizophrenia-specific chromatin modifications in neurons were particularly prominent for non-coding RNA genes, including an uncharacterized LINC01115 gene and recently identified BNRNA_052780. Notably, protein-coding genes with altered epigenetic state in schizophrenia are enriched for oxidative stress and cell motility pathways. Our results imply the rare individual epigenetic alterations in brain neurons are involved in the pathogenesis of schizophrenia
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