Vector Theory of Gravity

We proposed a gravitation theory based on an analogy with electrodynamics on the basis of a vector field. For the first time, to calculate the basic gravitational effects in the framework of a vector theory of gravity, we use a Lagrangian written with gravitational radiation neglected and generalized to the case of ultra-relativistic speeds. This allows us to accurately calculate the values of all three major gravity experiments: the values of the perihelion shift of Mercury, the light deflection angle in the gravity field of the Sun and the value of radar echo delay. The calculated values coincide with the observed ones. It is shown that, in this theory, there exists a model of an expanding Universe.Comment: 9 page

Taphonomic phenomenon of ancient hair from Glacial Beringia:perspectives for palaeoecological reconstructions

An accumulation of mammoth hair, discovered in the Bol'shaya Chukochya River valley (northeast Yakutia, Russia), was found to contain remains of terrestrial and aquatic organisms, including plants, insects, crustaceans, birds and mammals. Radiocarbon dating indicated that this post-mortem taphocoenosis represented multiple time periods. The mammoth hair was dated to older than 45 ka BP, the plants were dated to 12 750 +/- 50 a BP (which corresponds to a shift in the environmental conditions and landscapes during the formation of thermokarst in northeastern Russia) and the bird feathers were dated to 4115 +/- 40 a BP. A scenario of the formation of this fossil assemblage is proposed, covering the MIS 3-1 time range. The hair also yielded various Arctic branchiopod crustaceans, which inhabit shallow temporary water bodies and therefore are important for reconstruction of palaeoenvironments. The cladoceran subgenus Daphnia (Ctenodaphnia), currently absent from the Asian part of Beringia, is reported from this region for the first time. The study demonstrates that the discovered permafrostpreserved hair is a unique repository of Ice Age organisms.</p

ОСЛОЖНЕНИЯ ИЗОЛИРОВАННОЙ РЕГИОНАРНОЙ ХИМИОПЕРФУЗИИ КОНЕЧНОСТЕЙ

Currently, the methods of delivering high local doses of chemotherapy to locally-advanced tumors of the extremities, while avoiding systemic toxicity, are actively investigated. Isolated regional limb chemoperfusion is one of these methods. From 2004 to 2014, a total of 70 patients underwent isolated limb perfusion (ILP) for locally-advanced soft tissue sarcoma and transit metastases of extremity melanoma. Complications of ILP, causes of their occurrence and preventive measures were analyzed.В настоящее время активно изучаются методы локального воздействия на местно-диссеминированные опухоли конечностей, позволяющие избежать калечащей операции и сохранить высокое качество жизни больного. Одной из таких методик является изолированная регионарная химиоперфузия конечностей. Мы изучили данные по 70 больным, которым в отделении общей онко логии НИИ онкологии им. Н.Н. Петрова в период с 2004 по 2014  выполнена изолированная химиоперфузия по поводу местно распространенных сарком мягких тканей, а также транзитных метастазов меланомы конечностей. Представлен анализ возможных осложнений ИРП, причины их возникновения и возможные пути профилактики

Insects and molluscs of the Late Pleistocene at the Gornovo site (Southern Ural foreland, Russia): New data on palaeoenvironment reconstructions

The paper presents new data on the subfossil insects and molluscs, as well a new radiocarbon date for the Gornovo site in the Southern Fore-Urals. As a result, the stratigraphic interpretation of the sediments of the lower part of the first above floodplain terrace of the Belaya River is corrected and they are assigned to the Tabulda Horizon (MIS 3) of the Upper Pleistocene in the regional scheme of the Fore-Urals Quaternary. The malacofauna of the locality is represented by 27 species of terrestrial and freshwater molluscs. The composition of molluscs in the deposits of MIS 3 indicates the succession of deposit accumulation in the river valley from the stage of reservoirs that periodically connecting with the river to the stage of the overgrown oxbow lake. Single occurrence of mollusc shells in the loams of MIS 2 is a result of sharp climate change. New insect material includes 136 species of Coleoptera from 17 families, as well as Heteroptera and Hymenoptera representatives. 29 species of beetles (Carabidae, Histeridae, Scarabaeidae, Elateridae, Tenebrionidae, Chrysomelidae, Brentidae and Curculionidae) are recorded for the Pleistocene for the first time. The insect assemblages from Gornovo site are assigned to periglacial and humid boreal faunal types. The entomofauna of the periglacial type has no analogues in the recent fauna; it corresponds to the deposits assigned to the middle of MIS 3. This entomofauna is characteristic to the MIS 2 and MIS 3 insect assemblages from the south of West Siberian Plain. Based on entomological data, the climate of the middle of MIS 3 of the Southern Fore-Urals is reconstructed as dry and cold, extracontinental, with mean July temperature not exceeding +15 °C. Steppe landscapes likely prevailed in open areas and coniferous forests were restricted to river valleys. Beetles from deposits dated to end of MIS 3 are assigned to the fauna of the boreal humid type. These insect assemblages are significantly poorer in diversity than periglacial type assemblages and are represented mainly by near water and forest Coleoptera. Based on these species, meadow and forest landscapes were reconstructed. The reconstructed mean air temperature of July ranged from +16 to +19 °C. This suggests a trend towards more mild conditions in the region connected to the climate warming at the end of MIS 3. It is likely that humidification during this period was regional, determined by the proximity of the site to the Southern Urals Mountains. © 2021 Elsevier Ltd and INQU

Электронные состояния в металло-полимерном композите полипараксилилен - серебро

Cathodoluminescence spectra of polyparaxylylene - silver metallopolymeric composite were measured and analyzed. The band structure of the composite was investigated. The density of states and band gap were calculated. A model of energy transfer in the polymer matrix was suggested.Измерены и проанализированы спектры катодолюминесценции металлополимерного композита полипараксилилен-серебро, исследована зонная структура композита, рассчитана плотность состояний и ширина запрещенной зоны, предложена модель переноса энергии в полимерной матрице

КРЕМНИЕВЫЕ ПРИБОРНЫЕ СТРУКТУРЫ С ЭФФЕКТИВНОЙ ИЗЛУЧАТЕЛЬНОЙ РЕКОМБИНАЦИЕЙ НА ДИСЛОКАЦИЯХ Мудрый А.В.1, Живулько В.Д.1, Мофиднахаи Ф.1, Ивлев Г.Д.2, Якушев М.

The efficient electroluminescence in the region of band-to-band (1,1 eV) and dislocationrelated (D1 – 0,8 eV) transitions has been detected from Si p-n structures at room and liquid nitrogen temperatures. It was found that dislocation-related luminescence in Si single crystals is considerably stronger than the intrinsic band-to-band emission in the wide temperature range of 4,2–300 K. The temperature dependent measurement of the D1 photoluminescence intensity shows that two energy levels placed below the conduction (0,04 eV) and above valence (0,32 eV) bands are responsible for this radiative recombination on dislocations.В кремниевых p-n структурах обнаружена эффективная электролюминесценция в области переходов зона–зона (1,1 эВ) и переходов, обусловленных дислокациями (D1–0,8 эВ), при комнатной температуре и температуре жидкого азота. Установлено, что люминесценция, обусловленная дислокациями в монокристаллах Si, значительно сильнее, чем собственное межзонное излучение в интервале температур 4,2–300 К. Измерение температурной зависимости интенсивности полосы фотолюминесценции D1 показало, что за излучательную рекомбинацию на дислокациях ответственны два энергетических уровня, расположенных ниже зоны проводимости (≈ 0,04 эВ) и выше валентной зоны (≈ 0,32 эВ)

Mathematical Modelling of Cell-Fate Decision in Response to Death Receptor Engagement

Cytokines such as TNF and FASL can trigger death or survival depending on cell lines and cellular conditions. The mechanistic details of how a cell chooses among these cell fates are still unclear. The understanding of these processes is important since they are altered in many diseases, including cancer and AIDS. Using a discrete modelling formalism, we present a mathematical model of cell fate decision recapitulating and integrating the most consistent facts extracted from the literature. This model provides a generic high-level view of the interplays between NFκB pro-survival pathway, RIP1-dependent necrosis, and the apoptosis pathway in response to death receptor-mediated signals. Wild type simulations demonstrate robust segregation of cellular responses to receptor engagement. Model simulations recapitulate documented phenotypes of protein knockdowns and enable the prediction of the effects of novel knockdowns. In silico experiments simulate the outcomes following ligand removal at different stages, and suggest experimental approaches to further validate and specialise the model for particular cell types. We also propose a reduced conceptual model implementing the logic of the decision process. This analysis gives specific predictions regarding cross-talks between the three pathways, as well as the transient role of RIP1 protein in necrosis, and confirms the phenotypes of novel perturbations. Our wild type and mutant simulations provide novel insights to restore apoptosis in defective cells. The model analysis expands our understanding of how cell fate decision is made. Moreover, our current model can be used to assess contradictory or controversial data from the literature. Ultimately, it constitutes a valuable reasoning tool to delineate novel experiments

A New Methodology to Associate SNPs with Human Diseases According to Their Pathway Related Context

Genome-wide association studies (GWAS) with hundreds of żthousands of single nucleotide polymorphisms (SNPs) are popular strategies to reveal the genetic basis of human complex diseases. Despite many successes of GWAS, it is well recognized that new analytical approaches have to be integrated to achieve their full potential. Starting with a list of SNPs, found to be associated with disease in GWAS, here we propose a novel methodology to devise functionally important KEGG pathways through the identification of genes within these pathways, where these genes are obtained from SNP analysis. Our methodology is based on functionalization of important SNPs to identify effected genes and disease related pathways. We have tested our methodology on WTCCC Rheumatoid Arthritis (RA) dataset and identified: i) previously known RA related KEGG pathways (e.g., Toll-like receptor signaling, Jak-STAT signaling, Antigen processing, Leukocyte transendothelial migration and MAPK signaling pathways); ii) additional KEGG pathways (e.g., Pathways in cancer, Neurotrophin signaling, Chemokine signaling pathways) as associated with RA. Furthermore, these newly found pathways included genes which are targets of RA-specific drugs. Even though GWAS analysis identifies 14 out of 83 of those drug target genes; newly found functionally important KEGG pathways led to the discovery of 25 out of 83 genes, known to be used as drug targets for the treatment of RA. Among the previously known pathways, we identified additional genes associated with RA (e.g. Antigen processing and presentation, Tight junction). Importantly, within these pathways, the associations between some of these additionally found genes, such as HLA-C, HLA-G, PRKCQ, PRKCZ, TAP1, TAP2 and RA were verified by either OMIM database or by literature retrieved from the NCBI PubMed module. With the whole-genome sequencing on the horizon, we show that the full potential of GWAS can be achieved by integrating pathway and network-oriented analysis and prior knowledge from functional properties of a SNP

Robust simplifications of multiscale biochemical networks

<p>Abstract</p> <p>Background</p> <p>Cellular processes such as metabolism, decision making in development and differentiation, signalling, etc., can be modeled as large networks of biochemical reactions. In order to understand the functioning of these systems, there is a strong need for general model reduction techniques allowing to simplify models without loosing their main properties. In systems biology we also need to compare models or to couple them as parts of larger models. In these situations reduction to a common level of complexity is needed.</p> <p>Results</p> <p>We propose a systematic treatment of model reduction of multiscale biochemical networks. First, we consider linear kinetic models, which appear as "pseudo-monomolecular" subsystems of multiscale nonlinear reaction networks. For such linear models, we propose a reduction algorithm which is based on a generalized theory of the limiting step that we have developed in <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. Second, for non-linear systems we develop an algorithm based on dominant solutions of quasi-stationarity equations. For oscillating systems, quasi-stationarity and averaging are combined to eliminate time scales much faster and much slower than the period of the oscillations. In all cases, we obtain robust simplifications and also identify the critical parameters of the model. The methods are demonstrated for simple examples and for a more complex model of NF-<it>κ</it>B pathway.</p> <p>Conclusion</p> <p>Our approach allows critical parameter identification and produces hierarchies of models. Hierarchical modeling is important in "middle-out" approaches when there is need to zoom in and out several levels of complexity. Critical parameter identification is an important issue in systems biology with potential applications to biological control and therapeutics. Our approach also deals naturally with the presence of multiple time scales, which is a general property of systems biology models.</p