Different Stages Of Selection Research Articles

New protocol for rapid cassava multiplication in field conditions: a perspective on speed breeding.

Despite the economic and social importance, high-yielding cassava cultivars are only released after extensive research, mainly due to the low multiplication rate. This study aimed to assess the impact of using smaller-sized seed cuttings treated with agrochemicals (8MP) compared to the conventional planting size (16 cm) on genetic parameters, agronomic performance, and the ranking of cassava clones based on yield and growth attributes. The evaluation was carried out in clonal evaluation trial (CET), preliminary yield trial (PYT), and uniform yield trials (UYT). Additionally, a new selection scheme for cassava breeding programs was proposed. A total of 169 clones were evaluated, including 154 improved clones at different stages of selection and 15 local varieties used as checks. Field trials were conducted using both sizes of propagative material (8MP and 16 cm) in each phase of the breeding program. The data were analyzed using mixed models, considering the random effects of genotype and genotype-environment interaction (G×E) to determine variances and heritabilities. Bland-Altman concordance and correlation analysis of selection indices were employed to examine the consistency in the ranking of cassava clones using different seed cutting sizes. The distribution of variance components, heritabilities, means, and range of the 8MP and 16 cm trials in different phases of the cassava breeding program exhibited remarkable similarity, thereby enabling a comparative assessment of similar genetic effects. With a selection intensity of 30%, the concordance in clone ranking was 0.41, 0.57, and 0.85 in CET, PYT, and UYT trials, respectively, when comparing the selection based on 8MP and 16 cm trials. It is worth noting that the ranking of the top 15% remained largely unchanged. Based on the findings, proposed changes in the cassava selection scheme involve increasing the number of trials starting from the CET phase, early incorporation of G×E interaction, elimination of the PYT trial, reduction of the breeding cycle from 5 to 3 years, and a decrease in the time required for variety development from 11 to 9 years. These modifications are expected to lead to cost reduction and enhance the effectiveness of cassava breeding programs.

Acidic Growth Conditions Promote Epithelial-to-Mesenchymal Transition to Select More Aggressive PDAC Cell Phenotypes In Vitro.

Pancreatic Ductal Adenocarcinoma (PDAC) is characterized by an acidic microenvironment, which contributes to therapeutic failure. So far there is a lack of knowledge with respect to the role of the acidic microenvironment in the invasive process. This work aimed to study the phenotypic and genetic response of PDAC cells to acidic stress along the different stages of selection. To this end, we subjected the cells to short- and long-term acidic pressure and recovery to pHe 7.4. This treatment aimed at mimicking PDAC edges and consequent cancer cell escape from the tumor. The impact of acidosis was assessed for cell morphology, proliferation, adhesion, migration, invasion, and epithelial-mesenchymal transition (EMT) via functional in vitro assays and RNA sequencing. Our results indicate that short acidic treatment limits growth, adhesion, invasion, and viability of PDAC cells. As the acid treatment progresses, it selects cancer cells with enhanced migration and invasion abilities induced by EMT, potentiating their metastatic potential when re-exposed to pHe 7.4. The RNA-seq analysis of PANC-1 cells exposed to short-term acidosis and pHe-selected recovered to pHe 7.4 revealed distinct transcriptome rewiring. We describe an enrichment of genes relevant to proliferation, migration, EMT, and invasion in acid-selected cells. Our work clearly demonstrates that upon acidosis stress, PDAC cells acquire more invasive cell phenotypes by promoting EMT and thus paving the way for more aggressive cell phenotypes.

“New Balls Please”: Physical Load Imposed on Ball Boys during the Roland Garros 2022

The process of becoming a ball kid at the French Open consists of different stages of selection and training. Selection and training of the ball kids is organized by the French Federation of Tennis (FFT) and is intended to be an immersive and educational experience. A sample was made up of ball kids participating at the 2022 French Open (Roland Garros). For this study, 26 ball kids were analyzed during several rotations of their activity on the court with different durations (N = 26; age = 15.00 ± 0.84; height = 169.03 ± 9.62; weight = 52.26 ± 7.35). Each ball kid participated in several analyzed rotations (data entry N = 94). Two groups are analyzed: ball kids at the net and in the back of the court. The result of the statistical analysis showed a statistically significant difference between the two groups in the variables: meters covered per minute on court (t = 6.85, p = 0.00), total number of decelerations per minute (t = 8.39, p = 0.00), walking and jogging meters per minute (t = 4.68, p = 0.00), and maximum velocity achieved (t = 3.02, p = 0.00). Participating as a ball kid during a professional tournament presents a unique experience for young athletes. Young people that are participating can improve their fitness, social skills, mental abilities, and well-being due to requests for the ball kids' duties during match play and out of play activities.

The first selection for cosmonauts: from idea to implementation

In the article describes the evolution of the idea of human spaceflight in the post-war period, the formation of a selection system for cosmonauts. Attention is drawn to the fact that by the time of the International Geophysical Year (1957-1958) in the USSR there was an opportunity to send a person on a suborbital flight, but it was decided to finalize the equipment for an orbital mission. At the same time, on the basis of unpublished documents, the progress of the search for applicants for the first cosmonaut team is shown, the reasons for the pilots' refusals from further tests at different stages of selection are revealed.

INVESTIGATING LOCAL ITEM INDEPENDENCE IN CIVIC EDUCATION MULTIPLE-CHOICE ITEMS OF JOINT MOCK EXAMINATION

In preparation for external examinations, Senior Secondary School II students write joint mock examinations in core subjects including civic education. The study examined into the authenticity of civic education test multiple-choice items. A post-hoc research design was used. The population included all public school senior secondary I, II, and III students, whereas the target population included 2020/21 SSS II students. The Kwara State Ministry of Education and Human Capital Development created a 50-item multiple-choice item for the research. At different stages of selection, stratified, proportionate, and simple random sampling techniques were used. Using tetrachoric correlation statistics, one research question was posed and answered. Based on the thumb rule of 0.3, 41 of 50 items favoured local item independence. Local item dependency should be taught as part of psychometric properties in undergraduate and postgraduate progra

Applicability of an international linear appraisal system in Murciano-Granadina breed: fitting, zoometry correspondence inconsistencies, and improving strategies

Linear appraisal systems (LAS) are effective strategies to systematically collect zoometric information from animal populations. Traditionally applied LAS in goats was developed considering the variability and scales found in highly selected breeds. As a result, traditional LAS may no longer cover the different contexts of goat breeds widespread throughout the world, and departures from normality may be indicative of the different stages of selection at which a certain population can be found. The present study aimed to evaluate the distribution and symmetry properties of twenty-eight zoometric traits. After symmetry analysis was performed, the scale readjustment proposal suggested specific strategies should be implemented such as scale reduction of lower or upper levels, determination of a setup moment to evaluate and collect information from young (up to 2 years) and adult bucks (over 2 years), the addition of upper categories in males due to upper values in the scale being incorrectly clustered together. The particular analysis of each variable permits determining specific strategies for each trait and serve as a model for other breeds, either selected or in terms of selection. Highlights Specific strategies must be approached for each particular zoometric trait. Scale levels for limb related traits must be readjusted. An extension of the scale in the stature of males is proposed. Males must be subdivided into two categories (below and over two years). Environment adaptability shapes progress for better dairy-linked zoometry.

Selecting talent using social networks: A mixed-methods study

Previous studies on the use of Social Networking Sites (SNS) in personnel selection generally focus on examining this phenomenon in the selection process as a whole. However, personnel selection is a macro-process composed of several activities. This paper aims to investigate how human resource professionals use SNS in hiring decisions during the different stages of the selection process. The research uses an explanatory sequential mixed-methods approach. The first study consisted of a questionnaire-based survey of hiring professionals with the intent to describe various aspects of current practice (n = 429). Survey data was analyzed using descriptive and inferential statistics. The second study comprised semi-structured interviews with hiring professionals to provide a more in-depth, richer analysis (n = 24). Interview data was analyzed via qualitative thematic analysis. Results uncovered two types of users. Single-stage users emphasized efficiency concerns, whereas multiple-stage users mentioned to access profiles on an as needed-basis. Participants reported that the patterns of use could be quite complex and dynamic, with selectors revisiting the profile of the same applicant several times for different purposes, or examining profiles of the same applicant in different SNS. The assessment of SNS information is typically non-systematic, but some employers reported using scales, mainly in pre-selection. Evidence emerged of potential adverse effects during the selection process. Overall, this paper contributes to theory and practice by providing a better understanding of the use of SNS across the different stages of personnel selection. To our best knowledge, this is the first mixed-methods study of its kind.

Genomic prediction of sugar content and cane yield in sugar cane clones in different stages of selection in a breeding program, with and without pedigree information

High cane yield and commercially extractable sucrose (CCS) content are two of the key sugarcane commercial traits selected in sugarcane breeding programs. Advancements in genomic prediction may provide opportunities to speed up gains for these traits in breeding programs by combining accurate prediction of breeding values in candidate parent clones shortening generation intervals. Selection trials in commercial breeding programs may provide training populations for developing genomic predictions. In this study, three different populations of clones in early and advanced stage selection trials in an established commercial sugarcane breeding program were used to assess genomic prediction accuracy. The clones (genotypes) were evaluated for cane yield and sugar content in field trials and genotyped using a SNP array developed for sugarcane cultivars and parents. Five models (Bayes A, Bayes B, Bayesian LASSO, Bayesian GBLUP and RKHS) were tested using pedigree and/or marker data. Prediction models that included marker information had higher prediction accuracies than models with pedigree data only. For CCS, the prediction accuracies for genotypes in advanced stage trials using DNA markers were superior compared with prediction accuracies for early-stage trials, suggesting that prior intensive selection for CCS did not diminish accuracy of genomic prediction. However, by contrast, for cane yield, the prediction accuracies were much less for the population in the advanced stages of selection. The levels of prediction accuracy obtained in most datasets (0.25–0.45) are encouraging for developing applications of genomic prediction to predict breeding values of yield and sugar content in sugarcane breeding programs.

Genomic selection for productive traits in biparental cassava breeding populations.

Cassava improvement using traditional breeding strategies is slow due to the species’ long breeding cycle. However, the use of genomic selection can lead to a shorter breeding cycle. This study aimed to estimate genetic parameters for productive traits based on pedigree (pedigree and phenotypic information) and genomic (markers and phenotypic information) analyses using biparental crosses at different stages of selection. A total of 290 clones were genotyped and phenotyped for fresh root yield (FRY), dry matter content (DMC), dry yield (DY), fresh shoot yield (FSY) and harvest index (HI). The clones were evaluated in clonal evaluation trials (CET), preliminary yield trials (PYT), advanced yield trials (AYT) and uniform yield trials (UYT), from 2013 to 2018 in ten locations. The breeding stages were analyzed as follows: one stage (CET), two stages (CET and PYT), three stages (CET, PYT and AYT) and four stages (CET, PYT, AYT and UYT). The genomic predictions were analyzed via k-fold cross-validation based on the genomic best linear unbiased prediction (GBLUP) considering a model with genetic additive effects and genotype × location interactions. Genomic and pedigree accuracies were moderate to high (0.56–0.72 and 0.62–0.78, respectively) for important starch-related traits such as DY and FRY; when considering one breeding stage (CET) with the aim of early selection, the genomic accuracies ranged from 0.60 (DMC) to 0.71 (HI). Moreover, the correlations between the genomic estimation breeding values of one-stage genomic analysis and the estimated breeding values of the four-stage (full data set) pedigree analysis were high for all traits as well as for a selection index including all traits. The results indicate great possibilities for genomic selection in cassava, especially for selection early in the breeding cycle (saving time and effort).

Prototipo limpiador de frijol aplicando dispositivos lógicos programables

The project focuses on the cleaning of beans through the separation of impurities by screening machines, with the aim of helping small farmers who grow and sell their beans. Beans are among the most comsumed foods; however, the cleaning process is tedious, so we want to develop a system that performs such process in different stages of selection. Grains vary in price and quality in different places due to the conditions in which they are sold. This is because when they are sold in a supermarket, the product must be considered first level, which means, they must be of a homogeneous size and clean of any type of garbage. The purpose of this prototype is to clean the beans in such a way that it separates the impurities they might have and obtain a clean product. We begin by defining the cleaning procedure, then performing the structure and placement of sensors and actuators, and finally the programming and adjustments necessary for its operation. With this prototype, people who cultivate and extract the seeds can perform the cleaning and generate greater profits.

ВИРОБНИЧА ПЕРЕВІРКА СТРІЧКОВОГО ПРИСТРОЮ ДЛЯ АВТОМАТИЧНОГО ФЕНОТИПУВАННЯ НАСІННЯ СОНЯШНИКУ

When performing the breeding and seed production process, it is important to use marker traits that serve to establish the plant's affiliation to a particular hybrid or variety (prevent falsification) and quickly select a large number of plants at different stages of selection. Based on this, the development and improvement of technical and technological support for the automatic phenotyping test of sunflower seeds in the structure of systems for automated control of their structural and mode parameters is an urgent problem. The purpose of the research is to develop and perform a production test of a tape device for the automatic phenotyping test of sunflower seeds. A rational precision technological line of the processes of separation of sunflower seed material has been developed, which includes the stages of mechanically threshing baskets from under individual insulators and primary cleaning of the seed mixture, which is carried out on laboratory sieving and small aerodynamic separators using for automatic phenotyping test of seeds. The proposed sunflower device can significantly intensify and shorten the breeding process and improve the design of the breeding program. With the help of the specified device it is possible to carry out bioinformative analysis of the data, to carry out an assessment of their quality, to sort the seeds of oilseeds crops, to carry out the selection according to the given characteristics at the initial stages of the breeding process. A tape device for automatic phenotyping test of seeds has been developed, which preserves the accuracy of individual measurement of the geometric dimensions of sunflower seeds, determination of their shape and color, which corresponds to modern measuring tools, and provides low complexity and high technological implementation of the phenotyping test procedure (determination, identification) breeding material, its morphological and marker features

Radiocarbon Analysis of Samples by a 1-MV AMS Spectrometer at Ion Charge State 3+

Charge states 1+ and 2+ are usually used for ion selection in 1-MV AMS complexes. Charge state 3+ is used at the BINP AMS complex for the improved ion selection. A brief description of the BINP AMS complex, experimental results of ion separation at different stages of selection, and examples of radiocarbon dating of samples are presented.

A importância do e-recrutamento e seleção online no processo organizacional

Um dos processos realizados pelo setor de Recursos Humanos de uma organização é o Recrutamento e Seleção; esta, talvez seja uma das práticas mais realizadas pelas empresas e que possui diferentes formas a depender da necessidade e da cultura organizacional de cada uma delas, pois o que cada empresa busca na contratação de pessoas, são candidatos e futuros colaboradores aptos ao exercício da função. Surge, então, o objeto desta pesquisa, a utilização de ferramentas tecnológicas para este processo, a qual é denominada de e-recrutamento. . Portanto, o objetivo deste artigo é investigar a importância da utilização de ferramentas online no processo de Recrutamento e Seleção das organizações. E, para isto é preciso observar o uso de ferramentas online em processos de seleção à distância, como também averiguar o quanto a tecnologia pode auxiliar na aproximação com os candidatos e comparar as etapas de seleção presencialmente com as etapas online, observando as questões de tempo, economia, comunicação e disponibilidade dos candidatos em relação a cada uma delas. Desta forma, a metodologia utilizada foi a revisão sistemática da literatura e, foram pesquisados artigos científicos publicados no período de 2002 a 2014 encontrados nas bases de dados da SCIELO, PEPSIC E GOOGLE ACADÊMICO, além de livros das áreas de administração, recursos humanos e psicologia organizacional e do trabalho. Verificou-se, então, que a prática do e-recrutamento e a seleção online podem ser atendidas em diversas demandas que atualmente são apresentadas para a área organizacional e/ou recursos humanos, além de contribuir para efetivar de forma positiva nos quesitos aproximação e facilidade de comunicação entre candidatos e empresas, como maior dinamicidade, otimização do tempo e baixo custo nos processos e resultados.

Cassava Breeding II: Phenotypic Correlations through the Different Stages of Selection.

Breeding cassava relies on a phenotypic recurrent selection that takes advantage of the vegetative propagation of this crop. Successive stages of selection (single row trial–SRT; preliminary yield trial–PYT; advanced yield trial–AYT; and uniform yield trials UYT), gradually reduce the number of genotypes as the plot size, number of replications and locations increase. An important feature of this scheme is that, because of the clonal, reproduction of cassava, the same identical genotypes are evaluated throughout these four successive stages of selection. For this study data, from 14 years (more than 30,000 data points) of evaluation in a sub-humid tropical environment was consolidated for a meta-analysis. Correlation coefficients for fresh root yield (FRY), dry matter content (DMC), harvest index (HIN), and plant type score (PTS) along the different stages of selection were estimated. DMC and PTS measured in different trials showed the highest correlation coefficients, indicating a relatively good repeatability. HIN had an intermediate repeatability, whereas FRY had the lowest value. The association between HIN and FRY was lower than expected, suggesting that HIN in early stages was not reliable as indirect selection for FRY in later stages. There was a consistent decrease in the average performance of clones grown in PYTs compared with the earlier evaluation of the same genotypes at SRTs. A feasible explanation for this trend is the impact of the environment on the physiological and nutritional status of the planting material and/or epigenetic effects. The usefulness of HIN is questioned. Measuring this variable takes considerable efforts at harvest time. DMC and FRY showed a weak positive association in SRT (r = 0.21) but a clearly negative one at UYT (r = −0.42). The change in the relationship between these variables is the result of selection. In later stages of selection, the plant is forced to maximize productivity on a dry weight basis either by maximizing FRY or DMC, but not both. Alternatively, the plant may achieve high dry root yield by simultaneously attaining “acceptable” (but not maximum) levels of FRY and DMC.

Person–job fit versus person–organization fit as predictors of organizational attraction and job acceptance intentions: A longitudinal study

This longitudinal field study examined the relationship between perceived person–job (PJ) and person–organization (PO) fit and organizational attraction, intentions to accept a job offer, and actual job offer decision. Data were collected from 193 graduate applicants prior to the selection process, during the selection process, at the end of the selection process, and after job acceptance decision. The findings showed support for the hypothesis that perceptions of PJ and PO fit influenced attraction at different stages of selection. The second hypothesis that the relationship between perceptions of PJ and PO fit and intentions to accept a job offer are mediated by organizational attraction was partially supported. Mid‐selection, the relationship between PJ fit perceptions and intentions to accept a job offer was mediated by organizational attraction; in contrast, at the end of the selection process, there was a direct relationship between PJ fit perceptions and intentions. PO fit perceptions were unrelated to intentions to accept a job offer. PJ and PO fit perceptions (before and during the selection process) were unrelated to actual job acceptance decision. These findings highlight the importance of ensuring that applicants have sufficient information about the job during the recruitment and selection process.

Resistance of human immunodeficiency virus type 1 to protease inhibitors: selection of resistance mutations in the presence and absence of the drug

Inhibitors of the human immunodeficiency virus (HIV) protease are a promising class of antiviral agents that dramatically reduce HIV replication both in culture and in infected patients. However, as for many other antiviral compounds, long-term efficacy of these agents is impeded by the emergence of virus variants with increased resistance to their inhibitory action, following selection of specific mutations in the protease coding sequence. We have studied HIV-1 variants that emerged at different stages of selection in the presence of the C2-symmetrical protease inhibitor ABT-77003. The selection of variants was a gradual process during which mutations accumulated at different sites in the protease, generating virus populations with increasing levels of resistance to the drug. The initially selected viruses had a low level of resistance as well as a markedly reduced replicative capacity. Further accumulation of mutations at secondary sites led to an improvement in both drug resistance and replication. In spite of their reduced infectivity, partially selected virus populations did not readily revert to wild-type when serially passaged in drug-free conditions. Instead, even in the absence of drug, secondary mutations identical to those selected in the presence of the inhibitor continued to emerge. These mutations improved both the intrinsic replicative capacity of the virus and its level of resistance to the inhibitor, suggesting that once committed to drug resistance, readaptation of the enzyme to its natural substrate leads to a reduction of its sensitivity to the inhibitor.

Selection indices for sugarcane improvement at three stages of selection

Selection indices at different stages of selection were estimated for a biparental mating population of sugarcane (Saccharum officinarum L.). At the seedling stage indices constructed from primary characters are better than selection for yield alone. At the clonal stage the superiority of index selection over direct selection was marginal. In the seedling stage, selection based on index can lead to better selection efficiency in succeeding clonal stages. This was confirmed by a sample study.

Corrigendum - Response to selection in Australian Merino sheep. II. Estimates of phenotypic and genetic parameters for some production traits in Merino ewes and an analysis of the possible effects of selection on them

Estimates of heritabilities and of phenotypic and genetic correlations are given, based on extensive measurements on medium Peppin Merino ewes at 15–16 months of age. In general these substantiate results obtained by other workers and, in particular, confirm the high heritabilities of the traits measured. An effort has been made to try to detect possible changes in additive genetic variance for the trait under selection (clean wool weight). Estimates are obtained for data from animals at different stages of selection: (A) either unselected, or with little selection history, and (B and C) with varying amounts of selection. For stage A data the average estimated additive genetic variance was 0.31. There are problems involved in estimating from stage (B+C) data but an upper limit average value of 0.22 was obtained. Thus, although a decrease in additive genetic variance has occurred, its statistical significance is unknown and conclusions about the decrease must necessarily be tentative. In practically all cases the estimates of phenotypic and genetic correlations are of the same order of magnitude, and for the genetic correlations may be summarized as: See PDFAll other combinations of traits have negligible genetic correlations (in the range –0.20 to + 0.2).

Response to selection in Australian Merino sheep. II. Estimates of phenotypic and genetic parameters for some production traits in Merino ewes and an analysis of the possible effects of selection on them

Estimates of heritabilities and of phenotypic and genetic correlations are given, based on extensive measurements on medium Peppin Merino ewes at 15–16 months of age. In general these substantiate results obtained by other workers and, in particular, confirm the high heritabilities of the traits measured. An effort has been made to try to detect possible changes in additive genetic variance for the trait under selection (clean wool weight). Estimates are obtained for data from animals at different stages of selection: (A) either unselected, or with little selection history, and (B and C) with varying amounts of selection. For stage A data the average estimated additive genetic variance was 0.31. There are problems involved in estimating from stage (B+C) data but an upper limit average value of 0.22 was obtained. Thus, although a decrease in additive genetic variance has occurred, its statistical significance is unknown and conclusions about the decrease must necessarily be tentative. In practically all cases the estimates of phenotypic and genetic correlations are of the same order of magnitude, and for the genetic correlations may be summarized as: See PDFAll other combinations of traits have negligible genetic correlations (in the range –0.20 to + 0.2).