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2022 ◽  
Vol 23 (2) ◽  
pp. 853
Author(s):  
Yury Ilinsky ◽  
Mary Demenkova ◽  
Roman Bykov ◽  
Alexander Bugrov

Bacteria of the Wolbachia genus are maternally inherited symbionts of Nematoda and numerous Arthropoda hosts. There are approximately 20 lineages of Wolbachia, which are called supergroups, and they are designated alphabetically. Wolbachia strains of the supergroups A and B are predominant in arthropods, especially in insects, and supergroup F seems to rank third. Host taxa have been studied very unevenly for Wolbachia symbionts, and here, we turn to one of largely unexplored insect families: Acrididae. On the basis of five genes subject to multilocus sequence typing, we investigated the incidence and genetic diversity of Wolbachia in 41 species belonging three subfamilies (Gomphocerinae, Oedipodinae, and Podisminae) collected in Turkey, Kazakhstan, Tajikistan, Russia, and Japan, making 501 specimens in total. Our results revealed a high incidence and very narrow genetic diversity of Wolbachia. Although only the strains belonging to supergroups A and B are commonly present in present, the Acrididae hosts here proved to be infected with supergroups B and F without A-supergroup variants. The only trace of an A-supergroup lineage was noted in one case of an inter-supergroup recombinant haplotype, where the ftsZ gene came from supergroup A, and the others from supergroup B. Variation in the Wolbachia haplotypes in Acrididae hosts within supergroups B and F was extremely low. A comprehensive genetic analysis of Wolbachia diversity confirmed specific features of the Wolbachia allelic set in Acrididae hosts. This result can help to elucidate the crucial issue of Wolbachia biology: the route(s) and mechanism(s) of Wolbachia horizontal transmission.


2022 ◽  
Vol 2022 ◽  
pp. 1-14
Author(s):  
Eun Hak Lee ◽  
Kyoungtae Kim ◽  
Seung-Young Kho ◽  
Dong-Kyu Kim ◽  
Shin-Hyung Cho

As the mode share of the subway in Seoul has increased, the estimation of passenger travel routes has become a crucial issue to identify the congestion sections in the subway network. This paper aims to estimate the travel train of subway passengers in Seoul. The alternative routes are generated based on the train log data. The travel route is then estimated by the empirical cumulative distribution functions (ECDFs) of access time, egress time, and transfer time. The train choice probability is estimated for alternative train combinations and the train combination with the highest probability is assigned to the subway passenger. The estimated result is validated using the transfer gate data which are recorded on private subway lines. The result showed that the accuracy of the estimated travel train is shown to be 95.6%. The choice ratios for no-transfer, one-transfer, two-transfer, three-transfer, and four-transfer trips are estimated to be 53.9%, 37.7%, 6.5%, 1.5%, and 0.4%, respectively. Regarding the practical application, the passenger kilometers by lines are estimated with the travel route estimation of the whole network. As results of the passenger kilometer calculation, the passenger kilometer of the proposed algorithm is estimated to be 88,314 million passenger kilometer. The proposed algorithm estimates the passenger kilometer about 13% higher than the shortest path algorithm. This result implies that the passengers do not always prefer the shortest path and detour about 13% for their convenience.


Author(s):  
Navya Anna Raju ◽  
Divya Prasad ◽  
Puneethkumar M Srinivasappa ◽  
Ankush Biradar ◽  
Sandeep S. Gholap ◽  
...  

The discharge of CO2 into the atmosphere has become a crucial issue for mankind and a great threat to the environment due to escalating consequences of global warming. This grants...


2021 ◽  
Vol 43 (4) ◽  
pp. 447-461
Author(s):  
Łukasz Prus

The paper describes term of service in a totalitarian state as a basis for reducing the pension of officers employed in the security service in the years 1944–1990. The legislators decided to hold liable the officers of the communist political police by reducing their pensions again, 26 years after the transformation. In this aspect, the crucial issue is the concept of service in a totalitarian state. The thesis of the paper is that the qualification of service in a totalitarian state cannot be determined only by formal conditions, that is, the time and place of service, but should also take into account substantive criteria, especially violation of the fundamental rights of individuals by former officers.


2021 ◽  
Vol 11 (2) ◽  
pp. 194
Author(s):  
Ahmad Heki Sujiatmoko

The students’ motivation in learning has been a crucial issue for many researchers so far. It is because motivation takes an important role to support the students’ learning achievement. Hence, motivation cannot be separated from the teaching and learning activities conducted by the EFL teachers. This current research was aimed at investigating the elements of the students’ motivation in joining the EFL virtual learning activities using the zoom application during the covid 19 pandemic. The research applied a qualitative descriptive approach. To collect the data, the researcher observed one elective class and interviewed some students from the class investigated. The results revealed that the students’ motivation was mostly influenced by the positive effect related to the learning situations created by the teacher when using the zoom application to conduct the teaching and learning activities. This also implied that the zoom application could lead the teachers to think of being creative in conducting the virtual teaching and learning activities.


2021 ◽  
Vol 4/2021 (94) ◽  
pp. 19-37
Author(s):  
Ewa Prymon-Ryś ◽  
◽  
Agnieszka Galarowicz ◽  

Purpose: The purpose of the article is identification and evaluation of the most important changes that have occurred in the behavior of Polish consumers as a result of the pandemic lockdown introduced in 2020. The article presents the results of studies conducted during the epidemic restrictions from March 15 to May 4, 2020. Design/methodology/approach: The main aim of the research was to determine how these restrictions influenced the purchasing behavior and decisions made by consumers. In the polls, the technique of an internet survey was used, which was justified by the accepted form of remote communication imposed on the society in various spheres of activity. The subject of the research was the organization of free time, the organization of shopping in households, the frequency of purchases and the methods of shopping in stationary and online stores. Findings: The most important phenomena that have been observed include the growing importance of e-commerce and technologies supporting distance communication and online exchange. The share of FMCG in online purchases increased when compared with the pre-pandemic online purchases. Polish consumers reduced the frequency of purchases and limited their overall spending on everyday purchases. During the first wave of the pandemic, the crucial issue for consumers was time management as a result of increased professional and family responsibilities, or (a similar percentage of responses) of excess free time. Poles used information technologies – for communication, shopping, learning and entertainment, to cope with the imposed social isolation. This trend, as indicated by the results of subsequent studies, will continue. Research limitations/implications: The research was conducted at a particular moment of time, during the last 2 weeks of the first pandemic lockdown; therefore, the study cannot provide the measurement of observable effects of behavior changes during a longer time since the pandemic situation has been volatile. In the research, the snowball method of sampling, which has its own limitations, was adopted. Originality/value: The value of the article results from the outcomes of the survey conducted with the use of a research questionnaire originally designed for the purposes of this study and empirical research results obtained during the lockdown period, which allowed for observing changes in consumer behavior in real time.


Author(s):  
Yange Sun ◽  
Han Shao ◽  
Bencai Zhang

Ensemble classification is an actively researched paradigm that has received much attention due to increasing real-world applications. The crucial issue of ensemble learning is to construct a pool of base classifiers with accuracy and diversity. In this paper, unlike conventional data-streams oriented ensemble methods, we propose a novel Measure via both Accuracy and Diversity (MAD) instead of one of them to supervise ensemble learning. Based on MAD, a novel online ensemble method called Accuracy and Diversity weighted Ensemble (ADE) effectively handles concept drift in data streams. ADE mainly uses the following three steps to construct a concept-drift oriented ensemble: for the current data window, 1) a new base classifier is constructed based on the current concept when drift detect, 2) MAD is used to measure the performance of ensemble members, and 3) a newly built classifier replaces the worst base classifier. If the newly constructed classifier is the worst one, the replacement has not occurred. Comparing with the state-of-art algorithms, ADE exceeds the current best-related algorithm by 2.38% in average classification accuracy. Experimental results show that the proposed method can effectively adapt to different types of drifts.


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Omid Zarei ◽  
Leili Shokoohizadeh ◽  
Hadi Hossainpour ◽  
Mohammad Yousef Alikhani

Background. Shiga toxin-producing Escherichia coli (STEC) is known as a crucial zoonotic food-borne pathogen. A total of 257 raw chicken meat samples were collected from different markets in Hamadan, west of Iran, from January 2016 to May 2017. Materials and Methods. The samples were cultured in selective and differential culture media, and the virulence genes of E. coli isolates were analyzed by PCR assay. The antibiotic resistance patterns of E. coli isolates were determined by the disk diffusion method. The genetic relatedness of the E. coli O157 isolates was analyzed by ERIC-PCR. Results. In total, 93 (36% ± 3.12) of the isolates were identified as E. coli in this study. Based on serological and microbiological tests, 36 (38.7% ± 9.9), 7 (7.5% ± 5.35), and 12 (12.9% ± 6.81) of the E. coli isolates were characterized as STEC, enteropathogenic E. coli (EPEC), and attaching and effacing E. coli (AEEC) strains, respectively. A high level of resistance to nalidixic acid (91.4% ± 5.7), tetracycline (89.2% ± 6.31), ampicillin (82.8% ± 7.67), and trimotoprime-sulfametoxazole (71% ± 9.22) was detected among the E. coli isolates. The analysis of the ERIC-PCR results showed five different ERIC types among the E. coli O157 isolates. Conclusions. Based on our findings, control and check-up of poultry meats should be considered as a crucial issue for public health.


Webology ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 70-82
Author(s):  
Zeina Hassan Razaq

Securing any communication system where important data may be transmitted through the channel is a very crucial issue. One of the good solutions in providing security for the speech is to use speech scrambling techniques. The chaotic system used in security has properties that make it a good choice for scrambling speech signal and the optimisation algorithm can provide a perfect performance when used to enhance the hybrid of more than one method. In this paper, we suggest a system that uses an optimisation method, namely, particle swarm optimisation. The evaluation measures prove that the output of the optimisation method has better performance among the methods used in the comparison, including chaotic maps and hybrid chaotic maps.


Author(s):  
Boshra H. Namin ◽  
Torvald Øgaard ◽  
Jo Røislien

Incivility has been identified as a prevalent and crucial issue in workplaces and one that may be associated with detrimental effects on employees and organizational outcomes, such as turnover intention. Many studies have been published regarding the effects of incivility, but there is a lack of integrative reviews and meta-analyses. The aim of the present study is to conduct an early meta-analysis of the relationship between employees’ perceptions of workplace incivility and their turnover intentions. Six databases, including ISI Web of Science, PsychInfo, Scopus, Emerald, Hospitality & Tourism Complete, and Soc Index, were searched to identify empirical articles for this meta-analytical paper. The results of statistical meta-analyses and meta-regression suggest that there is a positive relationship between perceived incivility and turnover intentions in employees and that relationship is consistent across different sources of workplace incivility. However, we did observe a possible interaction effect of “supervisor” and “coworker incivility”. The results also suggest that the relationship between workplace incivility and turnover intention is stronger in the academic sector than in other industries and stronger in the United States than in other countries.


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