Stock Assessment of the Blue Swimmer Crab Portunus pelagicus (Linnaeus, 1766) from the Oman Coastal Waters

Abstract: The stock assessment of the blue swimmer crab, Portunus pelagicus was made based on monthly length frequency data collected from four landing sites along the Oman coasts on both Arabian and Oman Seas from January, 2011 to May, 2012. Age and growth have been estimated from the length-frequency distribution of up to 1000 specimens. Age composition was determined using Bhattacharya's method and the results showed that the maximum life span of P. pelagicus was about 15 months. Bertalanffy (1938) growth parameters didn't differ significantly between sexes and the obtained values of K were K = 1.85, 1.68 and 1.68 y -1 and CL values were 102.83, 109.57 and 108.46 mm for male, female and sexes combined, respectively. The values of total mortality coefficient (Z), natural mortality coefficient (M) and fishing mortality coefficient (F) were 7.85, 3.15 and 4.7 y -1 . The yield per recruit and SSB analysis showed that the crab stock is being exploited beyond its maximum biological limit, but the increasing of fishing mortality to the level which gives the maximum Y/R (83% of its current value) will accompanied with a negligible increase in Y/R (2.7%) and a considerable decrease in both biomass per recruit (21.1%) and spawning stock biomass (37.6%)

TraceSim: An alignment method for computing stack trace similarity

ABSTRACT: Software systems can automatically submit crash reports to a repository for investigation when program failures occur. A significant portion of these crash reports are duplicate, i.e., they are caused by the same software issue. Therefore, if the volume of submitted reports is very large, automatic grouping of duplicate crash reports can significantly ease and speed up analysis of software failures. This task is known as crash report deduplication. Given a huge volume of incoming reports, increasing quality of deduplication is an important task. The majority of studies address it via information retrieval or sequence matching methods based on the similarity of stack traces from two crash reports. While information retrieval methods disregard the position of a frame in a stack trace, the existing works based on sequence matching algorithms do not fully consider subroutine global frequency and unmatched frames. Besides, due to data distribution differences among software projects, parameters that are learned using machine learning algorithms are necessary to provide more flexibility to the methods. In this paper, we propose TraceSim – an approach for crash report deduplication which combines TF-IDF, optimum global alignment, and machine learning (ML) in a novel way. Moreover, we propose a new evaluation methodology for this task that is more comprehensive and robust than previously used evaluation approaches. TraceSim significantly outperforms seven baselines and state-of-the-art methods in the majority of the scenarios. It is the only approach that achieves competitive results on all datasets regarding all considered metrics. Moreover, we conduct an extensive ablation study that demonstrates the importance of each TraceSim’s element to its final performance and robustness. Finally, we provide the source code for all considered methods and evaluation methodology as well as the created datasets

Opposing Effects of Prior Infection versus Prior Vaccination on Vaccine Immunogenicity against Influenza A(H3N2) Viruses

Prior vaccination can alternately enhance or attenuate influenza vaccine immunogenicity and effectiveness. Analogously, we found that vaccine immunogenicity was enhanced by prior A(H3N2) virus infection among participants of the Ha Nam Cohort, Viet Nam, but was attenuated by prior vaccination among Australian Health Care Workers (HCWs) vaccinated in the same year. Here, we combined these studies to directly compare antibody titers against 35 A(H3N2) viruses spanning 1968–2018. Participants received licensed inactivated vaccines containing A/HongKong/4801/2014 (H3N2). The analysis was limited to participants aged 18–65 Y, and compared those exposed to A(H3N2) viruses circulating since 2009 by infection (Ha Nam) or vaccination (HCWs) to a reference group who had no recent A(H3N2) infection or vaccination (Ha Nam). Antibody responses were compared by fitting titer/titer-rise landscapes across strains, and by estimating titer ratios to the reference group of 2009–2018 viruses. Pre-vaccination, titers were lowest against 2009–2014 viruses among the reference (no recent exposure) group. Post-vaccination, titers were, on average, two-fold higher among participants with prior infection and two-fold lower among participants with 3–5 prior vaccinations compared to the reference group. Titer rise was negligible among participants with 3–5 prior vaccinations, poor among participants with 1–2 prior vaccinations, and equivalent or better among those with prior infection compared to the reference group. The enhancing effect of prior infection versus the incrementally attenuating effect of prior vaccinations suggests that these exposures may alternately promote and constrain the generation of memory that can be recalled by a new vaccine strain.Annette Fox, Louise Carolan, Vivian Leung, Hoang Vu Mai Phuong, Arseniy Khvorov, Maria Auladell, Yeu-Yang Tseng, Pham Quang Thai, Ian Barr, Kanta Subbarao, Le Thi Quynh Mai, H. Rogier van Doorn, and Sheena G. Sulliva

The Digital Economy

Целью данной работы является рассмотрение новой мировой тенденции в экономике. Это тенденция «цифровая экономика», о её развитии в России было заявлено на государственном уровне, что привлекает наше внимание к данной теме. Следовательно, нужно конкретно понимать, что из себя представляет «цифровая экономика», каковы её основные принципы, на чём основана, какие перспективы и угрозы в себе содержит.The purpose of this work is to consider a new world trend in the economy. This is the trend of "digital economy", its development in Russia was announced at the state level, which draws our attention to this topic. "What is reality?", "Some peculiarity", what are its main principles, what are the p rospects and threats in itself

Spatial-Temporal Distribution of the Palinurid and Scyllarid Phyllosoma Larvae in Oman Coastal Waters

The Bongo Net samples collected between 2005 and 2008 in the Sea of Oman and in the north-western part of the Arabian Sea (near Massirah Island) were analyzed, for a pilot assessment of seasonal and spatial distribution of the phyllosoma larvae. In the samples collected, 84% of all phyllosoma larvae were from the family Palinuridae, while the others were contributed by family Scyllaridae. All larvae of Panulirus homarus were in the first development stage and had a mean body length of 1.30±0.89mm. The phyllosoma larvae of the less abundant family Scyllaridae were in the second, third, and fourth development stages, which had a mean length of 2.3mm, 3.3mm and 4.63mm, respectively. In terms of seasonal changes, the phyllosoma larvae tend to appear in Omani waters in February, reaching their maximum numbers in April. The abundance of phyllosoma P. homarus was as much as twofold higher in the Arabian Sea compared to the Sea of Oman

Factor Analysis of XRF and XRPD Data on the Example of the Rocks of the Kontozero Carbonatite Complex (NW Russia). Part II: Geological Interpretation

Numerical comparison of mineralogical and geochemical data, which is required in a variety of geological applications, is a challenging task, especially when analyzing extensive sample collections. Herein, we apply factor analysis (FA) to a collection of 198 diffraction patterns of bulk rock samples from the Kontozero carbonatite complex. The mineralogical information hidden in the X-ray powder diffraction (XRPD) data is thereby squeezed down to a set of two dozen variables represented by factor scores (FS). The values of these FSs show a functional relationship with the contents of the minerals composing the rocks. Therefore, factor scores can be considered as a beneficial tool for rapid qualitative and semiquantitative analysis of the mineral composition of rocks. Supplementing principal component analysis (PCA) with FSs as independent variables characterizing the mineral content of rocks allows for the numerical comparison of mineralogical and geochemical data. By PCA, we reveal the main trends in the mineralogical and geochemical evolution of the investigated rocks of the Kontozero complex. Furthermore, the results are obtained in the very first stages of the research. This fact elucidates the potential use of the proposed technique in geological studies and mining

Management of accounts receivable at the enterprise: problems and solutions

Магистерская диссертация включает в себя введение, три главы, заключение, список использованных источников. В первой главе рассмотрены сущность и структура оборотного капитала, в т.ч . особое внимание уделено дебиторской задолженности, отражены основные причины ее возникновения, описаны факторы, влияющие на величину. Рассмотрен механизм анализа дебиторской задолженности и управления ей. Во второй главе дана характеристика ПАО «ММК», проведен анализ его финансового состояния. Выявлены тенденции в состоянии дебиторской задолженности и управления ей, определены причинно-следственные связи с возможными причинами сложившейся ситуации. В третьей главе обобщены проблемы, выявленные в результате анализа дебиторской задолженности, предложены мероприятия по сокращению дебиторской задолженности и проведен расчет результативности предложенных мер. В заключении сформированы основные выводы.The master's thesis includes an introduction, three chapters, a conclusion, and a list of sources used. In the first chapter, the essence and structure of working capital are considered, including special attention is paid to accounts receivable, the main causes of its occurrence are reflected, the factors affecting the amount are described. The mechanism of the analysis of accounts receivable and its management is considered. In the second chapter, the characteristics of PJSC MMK are given, an analysis of its financial condition is carried out. Trends in the state of accounts receivable and its management are revealed, cause-and-effect relationships with possible causes of the current situation are determined. The third chapter summarizes the problems identified as a result of the analysis of accounts receivable, suggests measures to reduce accounts receivable and calculates the effectiveness of the proposed measures. In conclusion, the main conclusions are formed