Sharply 2-transitive linear groups

A group G is sharply 2-transitive if it admits a faithful permutation representation that is transitive and free on pairs of distinct points. Conjecturally, for all such groups there exists a near-field N (i.e. a skew field that is distributive only from the left) such that G is isomorphic to the semidirect product of the multiplicative and additive groups of N. This is well known in the finite case. We prove this conjecture when G < GL(n,F) is a linear group. Here we have to assume that both the characteristic of the field F and the permutational characteristic of the group G (see Definition 2.1) are not equal to 2.Comment: 8 pages, revision matches accepted versio

ОПУХОЛИ НАДПОЧЕЧНЫХ ЖЕЛЕЗ: ДИАГНОСТИКА, ТАКТИКА ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ

Проанализированы результаты хирургического лечения 1134 пациентов по поводу опухолей надпочечных желез за период с 1996 по 2015 г. Разработан оптимальный протокол диагностики и лечения гормонально активных злокачественных опухолей надпочечников, инциденталом. Сформулированы показания к их хирургическому лечению, оценена возможность выполнения видеоассистирующих операций по поводу заболеваний надпочечных желез

Efficient pairwise RNA structure prediction and alignment using sequence alignment constraints

BACKGROUND: We are interested in the problem of predicting secondary structure for small sets of homologous RNAs, by incorporating limited comparative sequence information into an RNA folding model. The Sankoff algorithm for simultaneous RNA folding and alignment is a basis for approaches to this problem. There are two open problems in applying a Sankoff algorithm: development of a good unified scoring system for alignment and folding and development of practical heuristics for dealing with the computational complexity of the algorithm. RESULTS: We use probabilistic models (pair stochastic context-free grammars, pairSCFGs) as a unifying framework for scoring pairwise alignment and folding. A constrained version of the pairSCFG structural alignment algorithm was developed which assumes knowledge of a few confidently aligned positions (pins). These pins are selected based on the posterior probabilities of a probabilistic pairwise sequence alignment. CONCLUSION: Pairwise RNA structural alignment improves on structure prediction accuracy relative to single sequence folding. Constraining on alignment is a straightforward method of reducing the runtime and memory requirements of the algorithm. Five practical implementations of the pairwise Sankoff algorithm – this work (Consan), David Mathews' Dynalign, Ian Holmes' Stemloc, Ivo Hofacker's PMcomp, and Jan Gorodkin's FOLDALIGN – have comparable overall performance with different strengths and weaknesses

The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2002

Called for by the U.S. Coral Reef Task Force’s (USCRTF) National Action Plan to Conserve Coral Reefs, this is the first biennial report on the condition of coral reefs. It is the scientific baseline for subsequent reports on the health of U.S. coral reef ecosystems that are to be used by NOAA and others to evaluate the efficacy of coral reef conservation and management practices. The National Oceanic and Atmospheric Administration’s National Ocean Service led the development of this report. It was authored by 38 experts and supported by 79 contributors from government agencies and non-governmental organizations across the nation and internationally. Over 100 Task Force members and other notable scientists have reviewed this document

Six priorities to advance the science and practice of coral reef restoration worldwide

Coral reef restoration is a rapidly growing movement galvanized by the accelerating degradation of the world's tropical coral reefs. The need for concerted and collaborative action focused on the recovery of coral reef ecosystems coalesced in the creation of the Coral Restoration Consortium (CRC) in 2017. In March 2020, the CRC leadership team met for a biennial review of international coral reef restoration efforts and a discussion of perceived knowledge and implementation bottlenecks that may impair scalability and efficacy. Herein we present six priorities wherein the CRC will foster scientific advancement and collaboration to: (1) increase restoration efficiency, focusing on scale and cost-effectiveness of deployment; (2) scale up larval-based coral restoration efforts, emphasizing recruit health, growth, and survival; (3) ensure restoration of threatened coral species proceeds within a population-genetics management context; (4) support a holistic approach to coral reef ecosystem restoration; (5) develop and promote the use of standardized terms and metrics for coral reef restoration; and (6) support coral reef restoration practitioners working in diverse geographic locations. These priorities are not exhaustive nor do we imply that accomplishing these tasks alone will be sufficient to restore coral reefs globally; rather these are topics where we feel the CRC community of practice can make timely and significant contributions to facilitate the growth of coral reef restoration as a practical conservation strategy. The goal for these collective actions is to provide tangible, local-scale advancements in reef condition that offset declines resulting from local and global stressors including climate change

Современные подходы к таргетной биопсии предстательной железы

Prostate cancer (PCa) is in second place in oncological morbidity in males and is the fifth leading cause of death among the world's population. According to current world statistics, over the past 20 years there has been an increase in primary morbidity, as well as mortality from PCa. The key to diagnosing PCa is a prostate biopsy. Nevertheless, a systemic biopsy under transrectal ultrasound control is the subject of discussion and debate in oncourology, as it has significant drawbacks that affect the qualitative result of the diagnosis of PCa. Given the importance of adequate and staged PCa, various methods of targeted biopsy under magnetic resonance control have been proposed.This review will examine the main features and significance of targeted prostate biopsy, as well as the role of magnetic resonance imaging in the early diagnosis of PCa. The method of targeted biopsy of the prostate gland can improve the detection of PCa in relation to clinically significant forms. In addition, this method is extremely promising and requires further study to further improve the quality of early diagnosis of PCa, especially when selecting patients for radical surgical treatment.Рак предстательной железы (РПЖ) занимает 2-е место в структуре онкологической заболеваемости мужчин и 5-е место среди причин смерти населения в мире. Согласно данным мировой статистики в течение последних 20 лет отмечается рост первичной заболеваемости РПЖ, а также смертности от него. Основным методом диагностики РПЖ является биопсия предстательной железы. Тем не менее системная биопсия под трансректальным ультразвуковым контролем остается предметом дискуссии в онкоурологии, так как имеет значимые недостатки, которые влияют на качественный результат диагностики РПЖ. С учетом важности стадирования данного заболевания были предложены различные способы прицельной биопсии под магнитно-резонансным контролем.В настоящем обзоре рассмотрены основные особенности и значимость таргетной биопсии предстательной железы, а также роль магнитно-резонансной томографии в ранней диагностике РПЖ. Таргетная биопсия предстательной железы позволяет улучшить показатели выявления РПЖ в отношении клинически значимых форм. Данный способ является крайне перспективным и требует дальнейшего изучения для дальнейшего повышения качества ранней диагностики РПЖ, особенно при отборе пациентов для радикального хирургического лечения

The role of leukocyte-stromal interactions in chronic inflammatory joint disease

Rheumatoid arthritis (RA) is a debilitating, chronic, persistent inflammatory disease that is characterised by painful and swollen joints. The aetiology of RA is unknown, however whereas past research has concentrated on the role of immune or inflammatory infiltrating cells in inflammation, it is becoming clear that stromal cells play a critical part in regulating the quality and duration of an inflammatory response. In this review we assess the role of fibroblasts within the inflamed synovium in modulating immune responses; in particular we examine the role of stromal cells in the switch from resolving to persistent inflammation as is found in the rheumatoid synovium

Financialization in Commodity Markets: Disentangling the Crisis from the Style Effect

In this paper, we show that large inflows into commodity investments, a recent phenomenon known as financialization, has changed the behavior and dependence structure between commodities and the general stock market. The common perception is that the increase in comovements is the result of distressed investors selling both assets during the 2007-2009 financial crisis. We show that financial distress alone cannot explain the size and persistence of comovements. Instead, we argue that commodities have become an investment style for institutional investors. Given that institutional investors continue to target funds into commodities, we predict spillovers between commodities and the stock market to remain high in the future

Incorporating phylogenetic-based covarying mutations into RNAalifold for RNA consensus structure prediction

BACKGROUND: RNAalifold, a popular computational method for RNA consensus structure prediction, incorporates covarying mutations into a thermodynamic model to fold the aligned RNA sequences. When quantifying covariance, it evaluates conserved signals of two aligned columns with base-pairing rules. This scoring scheme performs better than some other approaches, such as mutual information. However it ignores the phylogenetic history of the aligned sequences, which is an important criterion to evaluate the level of sequence covariance. RESULTS: In this article, in order to improve the accuracy of consensus structure folding, we propose a novel approach named PhyloRNAalifold. It incorporates the number of covarying mutations on the phylogenetic tree of the aligned sequences into the covariance scoring of RNAalifold. The benchmarking results show that the new scoring scheme of PhyloRNAalifold can improve the consensus structure detection of RNAalifold. CONCLUSION: Incorporating additional phylogenetic information of aligned sequences into the covariance scoring of RNAalifold can improve its performance of consensus structures folding. This improvement is correlated with alignment characteristics, such as pair-wise identity and the number of sequences in the alignment