57 research outputs found
Technology for designing an individual educational trajectory of university students
The continuity of education has to ensure the possibility of a person’s multidimensional progression of a person in the educational space and create optimal conditions for such progression. The continuous education system is currently one of the priorities in the state development policy in Russi
СОВРЕМЕННЫЕ МЕТОДЫ ЛЕЧЕНИЯ РЕЦИДИВНОГО НЕОПЕРАБЕЛЬНОГО ПЛОСКОКЛЕТОЧНОГО РАКА ГОРТАНИ (ОБЗОР ЛИТЕРАТУРЫ)
The literature review presents the modern methods of treatment of inoperable recurrent squamous cell cancer of the larynx. The application of radiation and chemotherapy.В обзоре литературы представлены данные о современных методах лечения неоперабельного рецидивного плоскоклеточного рака гортани. Рассматриваются вопросы применения лучевой и лекарственной терапии
ЛУЧЕВАЯ ТЕРАПИЯ НЕРЕЗЕКТАБЕЛЬНОГО РАКА ГОРТАНИ
The treatment outcomes of unresectable laryngeal cancer have been presented. The techniques of radiation therapy (RT) alone and concurrent chemoradiotherapy (CRT), as well as the effect of changes in the fractionation regimens on the treatment outcome have been analyzed. No differences in overall survival (OS) and locoregional control (LC) between the RT and CRT techniques were found (p<0.8). There is a trend toward improvement in OS (p<0.1) and LC (p<0.05) in laryngeal cancer patients treated with hyperftactionated radiation therapy.Представлены результаты лучевого лечения нерезектабельного плоскоклеточного рака гортани. Проанализированы методики самостоятельной лучевой терапии и одновременного химиолучевого лечения, а также влияние изменения режима фракционирования на результаты лечения в целом. Исходя из полученных данных, можно сделать вывод, что между методами только лучевой и химиолучевой терапии нет достоверных различий в показателях как общей выживаемости, так и локорегионарного контроля (p<0,8). Имеется тенденция к улучшению показателей общей выживаемости (p<0,1), а также достоверные данные об увеличении степени локорегионарного контроля (p<0,05) при облучении в режиме гиперфракционирования
Three-dimensional quantization of the electromagnetic field in dispersive and absorbing inhomogeneous dielectrics
A quantization scheme for the phenomenological Maxwell theory of the full
electromagnetic field in an inhomogeneous three-dimensional, dispersive and
absorbing dielectric medium is developed. The classical Maxwell equations with
spatially varying and Kramers-Kronig consistent permittivity are regarded as
operator-valued field equations, introducing additional current- and
charge-density operator fields in order to take into account the noise
associated with the dissipation in the medium. It is shown that the equal-time
commutation relations between the fundamental electromagnetic fields
and and the potentials and in the Coulomb gauge
can be expressed in terms of the Green tensor of the classical problem. From
the Green tensors for bulk material and an inhomogeneous medium consisting of
two bulk dielectrics with a common planar interface it is explicitly proven
that the well-known equal-time commutation relations of QED are preserved
Современные возможности консервативного и комбинированного лечения местнораспространенного рака гортани
The comparative analysis of results of conservative and combined treatment was carried out. The study group consisted of 400 patients with stage T3–4N0–3M0 laryngeal cancer who received concurrent chemotherapy and radiation therapy in combination with various physical radiomodifyers. The control group comprised 920 patients treated with the same technique but without systemic polychemotherapy. The 5-year relapse-free and overall survival rates were significantly higher in the study group than in the control group (concervative treatment: 71 % and 86 % versus 37 % and 64.8 %, respectively, р<0,001 and combined treatment: 80 % and 83 % versus 47.4 % and 52 %, respectively(р<0,001). The functional organ was preserved in 71.2 % of locally advanced laryngeal cancer patients treated conservatively compared to 37.0 % of the control group patients. Oprgan-preserving surgeries were performed in 30.5% and 23%, respectively. The total number of patients with the larynx preservation was 50 % of the stydy group and 31.6 % of the control group.Проведен сравнительный анализ результатов консервативного и комбинированного лечения 400 больных (основная группа) раком гортани T3–4N0–3M0 стадии, которым применялась одновременная химиолучевая терапия в сочетании с различными физиче-скими радиомодификаторами и 920 пациентов (контрольная группа), пролеченных по аналогичным методикам, но без применения системной полихимиотерапии. Получено значимое повышение 5-летней безрецидивной и общей выживаемости в основной группе как при консервативном – 71 % и 86 %, в контрольной группе – 37 % (р<0,001) и 64,8 % (р<0,001), так и при комбинированном лечении – 80 % и 83 %, в контрольной группе – 47,4 % (р<0,001) и 52 % (р<0,001) соответственно. Сохранен функционирующий орган у 71,2 % больных местнораспространенным раком гортани при консервативном лечении по сравнению с 37,0 % в контроле, органосохраняющие хирургические вмешательства удалось провести у 30,5 % и 23,0 % пациентов соответственно. Всего гортань сохранена у 50 % больных основной группы, в контрольной – у 31,6 %
Multigene phylogeny of the Mustelidae: Resolving relationships, tempo and biogeographic history of a mammalian adaptive radiation
<p>Abstract</p> <p>Background</p> <p>Adaptive radiation, the evolution of ecological and phenotypic diversity from a common ancestor, is a central concept in evolutionary biology and characterizes the evolutionary histories of many groups of organisms. One such group is the Mustelidae, the most species-rich family within the mammalian order Carnivora, encompassing 59 species classified into 22 genera. Extant mustelids display extensive ecomorphological diversity, with different lineages having evolved into an array of adaptive zones, from fossorial badgers to semi-aquatic otters. Mustelids are also widely distributed, with multiple genera found on different continents. As with other groups that have undergone adaptive radiation, resolving the phylogenetic history of mustelids presents a number of challenges because ecomorphological convergence may potentially confound morphologically based phylogenetic inferences, and because adaptive radiations often include one or more periods of rapid cladogenesis that require a large amount of data to resolve.</p> <p>Results</p> <p>We constructed a nearly complete generic-level phylogeny of the Mustelidae using a data matrix comprising 22 gene segments (~12,000 base pairs) analyzed with maximum parsimony, maximum likelihood and Bayesian inference methods. We show that mustelids are consistently resolved with high nodal support into four major clades and three monotypic lineages. Using Bayesian dating techniques, we provide evidence that mustelids underwent two bursts of diversification that coincide with major paleoenvironmental and biotic changes that occurred during the Neogene and correspond with similar bursts of cladogenesis in other vertebrate groups. Biogeographical analyses indicate that most of the extant diversity of mustelids originated in Eurasia and mustelids have colonized Africa, North America and South America on multiple occasions.</p> <p>Conclusion</p> <p>Combined with information from the fossil record, our phylogenetic and dating analyses suggest that mustelid diversification may have been spurred by a combination of faunal turnover events and diversification at lower trophic levels, ultimately caused by climatically driven environmental changes. Our biogeographic analyses show Eurasia as the center of origin of mustelid diversity and that mustelids in Africa, North America and South America have been assembled over time largely via dispersal, which has important implications for understanding the ecology of mustelid communities.</p
Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations
Background: Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts?
Results: In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these.
Conclusions: The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies
An approach to the development of clustering algorithms with a combined use of the Variable Neighborhood Search and Greedy Heuristic Method
Ordovician Paracrinoids from the Baltic: Key Problems of Comparative Morphology of Pelmatozoan Echinoderms
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