scholarly journals Monitoring field establishment of the emerald ash borer biocontrol agent Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae): Sampling methods, sample size, and phenology

2021 ◽  
Vol 156 ◽  
pp. 104535
Author(s):  
Toby R. Petrice ◽  
Leah S. Bauer ◽  
Deborah L. Miller ◽  
John S. Stanovick ◽  
Therese M. Poland ◽  
...  
2018 ◽  
Vol 4 (2) ◽  
pp. 205630511877283 ◽  
Author(s):  
Hwalbin Kim ◽  
S. Mo Jang ◽  
Sei-Hill Kim ◽  
Anan Wan

Despite the existing evaluation of the sampling options for periodical media content, only a few empirical studies have examined whether probability sampling methods can be applicable to social media content other than simple random sampling. This article tests the efficiency of simple random sampling and constructed week sampling, by varying the sample size of Twitter content related to the 2014 South Carolina gubernatorial election. We examine how many weeks were needed to adequately represent 5 months of tweets. Our findings show that a simple random sampling is more efficient than a constructed week sampling in terms of obtaining a more efficient and representative sample of Twitter data. This study also suggests that it is necessary to produce a sufficient sample size when analyzing social media content.


2019 ◽  
Vol 54 (4) ◽  
pp. 373-385 ◽  
Author(s):  
David Marancik ◽  
Jason Collins ◽  
Josephine Afema ◽  
Christian Lawrence

Examining zebrafish populations for the presence of disease is an integral component of managing fish health in research facilities. Currently, many different strategies are used for zebrafish fish health inspections, which is a scenario that may result in subjective and biased diagnostic evaluations. The goal of this study was to compare the success of pathogen detection between a sample size of randomly selected fish ( n = 60) that provides 95% confidence in pathogen detection based on a presumed pathogen prevalence level ≥5%, and other subpopulations and sample numbers commonly submitted for diagnostic testing within a 1000 tank, 30,000 fish, recirculating research system. This included fish collected from a sump tank ( n = 53), sentinel fish ( n = 11), and fish that were found moribund or freshly dead ( n = 18). Additionally, five fish from each subpopulation were collected for histopathologic examination. A second study used retrospective data to examine pathogen distribution between systems ( n = 2−5) in multi-system facilities ( n = 5) using a sample size of 60 fish per system. For the pathogens detected, results supported the use of representative sample numbers rather than smaller numbers of populations considered more at risk. The exception to this is for the moribund/mortality group, which may be a resource for targeted surveillance of select pathogens. Each system within multi-system facilities should be considered separate units in terms of fish health inspections and biosecurity. Development of these evidence-based standards for fish health inspections in zebrafish systems enhances fish welfare, provides identification of potentially zoonotic pathogens, and ensures scientific integrity and reproducibility of research results.


2020 ◽  
Vol 113 (6) ◽  
pp. 2657-2665
Author(s):  
Narin Srei ◽  
Claude Guertin ◽  
Robert Lavallée ◽  
Marie-Ève Lajoie ◽  
Christian Brousseau ◽  
...  

Abstract The FraxiProtec, an autodissemination device loaded with the fungus Beauveria bassiana isolate CFL-A, was tested in the field to evaluate its potential to infect emerald ash borer adults and reduce their populations. During the 2-yr experimental period, the dispersion of B. bassiana-infected adults was also documented to assess the dissemination capacity of the biocontrol agent beyond the treated areas. The mean percentage of infected emerald ash borer in 2017 and 2018 in 15 treated sites was 43.3 ± 2.9% and 39.7 ± 3.9%, respectively, and no significant variation was observed over the tested years. Furthermore, a 40% significant reduction of the mean emerald ash borer population growth per tree in treated sites was recorded when compared to the control sites. Emerald ash borer infected with B. bassiana isolate CFL-A were collected from baited sticky traps in the sentinel stations in the area surrounding the FraxiProtec-treated sites. Even at a distance of 125 m, an average of 9.4 ± 2.6% infected emerald ash borer were collected. Finally, exploratory analyzes were carried out on parameters such as the area to be treated, ash tree density, and FraxiProtec density to document potential relationships, which could be used in the determination of a prescription.


1971 ◽  
Vol 103 (1) ◽  
pp. 67-71 ◽  
Author(s):  
P. H. Westigard ◽  
L. D. Calvin

AbstractStudies were conducted in southern Oregon pear orchards to develop sampling methods for assessment of mite abundance. Those species included in the investigation were the two-spotted spider mite, Tetranychus urticae Koch; European red mite, Panonychus ulmi (Koch); yellow spider mite, Eotetranychus carpini borealis (Ewing); and the predaceous phytoseiid Typhlodromus occidentalis Nesbitt.The results show that five leaves on one limb per tree are adequate to include representative numbers of the four mite species. Variation in mite densities between trees, even of the same variety, was quite high. The sample size (numbers of trees) required for assessing mite density can be calculated provided that an estimate of the coefficient of variation (S/X) is available.


2021 ◽  
Vol 9 (5) ◽  
pp. 11
Author(s):  
Favourate Y Sebele-Mpofu

Sampling is one of the most controversial matters in qualitative research. Qualitative researchers have often been denounced for not giving adequate rationalisations for their sample size resolutions. This study aimed to provide an extensive review of sampling methods used in qualitative research and discuss the extent to which saturation might help alleviate the issues concerning these methods, sample size sufficiency and when to sample. The study specifically honed on the sampling adequacy (how big or how small should a sample be), the sampling techniques used and whether sample sizes should be delineated a priori, posteriori or during analysis. Having highlighted, the paradoxically nature of these aspects, through an overview of the sampling process, the researcher explored saturation as a tool to alleviate the challenges and the lack of objectivity in sampling in qualitative research. The overall findings were that, saturation does provide same degree of transparency and quality in sampling, but the concept is not immune to controversy, guidelines on how to apply it or achieve it remain foggy and contestable among researchers. Discussions are in most cases oversimplified and comparatively unknowledgeable. The answer to the research question, was that, what really constitutes an adequate sample size is only answerable within the context of the study, scientific paradigm, epistemological stance, ontological and methodological assumptions of the research conducted. Contextualisation of the mode of saturation adopted, clear articulation of the research methodology and transparent reporting of the whole process is key to enhance the role of saturation in alleviating subjectivity in sampling. This paper sought to make a contribution to the on-going methodological discourse on how qualitative researchers can justify their sampling decisions.


Culture modification may be a term employed in public political affairs that emphasizes the influence of cultural capital on individual and community behavior. it's been generally known as positioning of culture,which suggests the reconstruction of the cultural idea of a society.there is no significant difference between traditional culture and age . The aim to understand about cultural changes in chennai . For research methodology we use discripitive methods is used For the aim of the study ,descriptive analysis .for sampling methods Convenience sampling ways is employed. For Sample size 1480 samples. Independent variable such as Age ,Monthly financial gain,Gender,educational qualifications . Dependent are variable , ancient culture ,Changes in culture ,Social mediaWorship ,traditional ,spending,time,outdoors game.Statisticspercentage analysis ,Chi square ,Correlation ,Independent sample t check ,Anova. the sample size about 1480 .From this research it was found the cultural changes is mainly caused about people forgot of traditional cultures. The main courses of cultural changes is social media .From the research I found cultural changes is mostly increased in the city’s then I give suggestions people want follow traditions culture


Author(s):  
Syed Hammad Mian ◽  
Abdulrahman M Al-Ahmari

The selection of appropriate sample size and point distribution on the measuring surface has been a fundamental problem in the contemporary coordinate metrology. It is usually resolved by the users depending on their instinct or prior experience. As a result, inspection results have to be compromised between accuracy and measurement time. However, to deliver quality products in minimum time, effort, and cost, a reliable and an efficient sampling plan is mandatory. Although there have been a remarkable progress due to the development of various procedures for computing the sample size and selecting the appropriate point distribution, still users are inconversant with the characteristics and applications of the available sampling methods due to the absence of a proper review. Accordingly, a systematic review, giving insight into the various strategies available for the sample size and the point distribution, is presented. In this article, different algorithms and their application in the estimation of sample size and point distribution have been reviewed comprehensively. The classification of sampling methods and the importance of adaptive sampling have also been described. It has been concluded that the effectiveness of inspection process or the performance of coordinate measuring machine can be escalated through the application of a suitable sampling strategy. Therefore, the metrologists should either develop an effective method for defining sampling strategy or select the most suitable method from the available resources before carrying out the inspection process.


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