Tag: statistics

J Insect Sci. 2021 Mar 1;21(2):2. doi: 10.1093/jisesa/ieaa149.

ABSTRACT

Insecticide exposure has been identified as a contributing stressor to the decline in the North American monarch butterfly Danaus plexippus L. (Lepidoptera: Nymphalidae) population. Monarch toxicity data are currently limited and available data focuses on lethal endpoints. This study examined the 72-h toxicity of two pyrethroid insecticides, bifenthrin and β-cyfluthrin, and their effects on growth and diet consumption. The toxicity of bifenthrin to caterpillars was lower than β-cyfluthrin after 72 h. Survival was the most sensitive endpoint for bifenthrin, but diet consumption and caterpillar growth were significantly reduced at sublethal levels of β-cyfluthrin. Using AgDRIFT spray drift assessment, the aerial application of bifenthrin or β-cyfluthrin is predicted to pose the greatest risk to fifth-instar caterpillars, with lethal insecticide deposition up to 28 m for bifenthrin and up to 23 m for β-cyfluthrin from treated edges of fields. Low boom ground applications are predicted to reduce distances of lethal insecticide exposure to 2 m from the treated field edge for bifenthrin and β-cyfluthrin. Growth and survival of fifth-instar monarch caterpillars developing within the margins of a treated field may be significantly impacted following foliar applications of bifenthrin or β-cyfluthrin. These findings provide evidence that pyrethroid insecticides commonly used for soybean pest control are a potential risk to monarch caterpillars in agricultural landscapes.

PMID:33686432 | DOI:10.1093/jisesa/ieaa149

Phys Ther. 2021 Mar 3:pzab078. doi: 10.1093/ptj/pzab078. Online ahead of print.

ABSTRACT

OBJECTIVE: The purpose of this study is to explore academic faculty, employer, and recent graduate perspectives of the work-readiness of Australian new graduate physical therapists for private practice and factors that influence new graduate preparation and transition to private practice.

METHODS: This study used a mixed-methods design with 3 surveys and 12 focus groups. One hundred and twelve participants completed a survey and 52 participated in focus groups. Descriptive statistics were utilized to summarize the quantitative data and thematic analysis was used to analyze the qualitative data. Triangulation across participant groups and data sources was undertaken.

RESULTS: Australian new graduate physical therapists were perceived to be “somewhat ready” for private practice and “ready” by their third year of employment. Participants proposed that new graduates bring enthusiasm, readiness to learn, and contemporary, research-informed knowledge. New graduates were also perceived to find autonomous clinical reasoning and timely caseload management difficult; to have limited business, marketing and administration knowledge and skills; and to present with underdeveloped confidence, communication, and interpersonal skills. Factors perceived to influence graduate transition included private practice experience, such as clinical placements and employment; employer and client expectations of graduate capabilities; workplace support; university academic preparation and continuing education; and individual graduate attributes and skills.

CONCLUSION: Australian new graduate physical therapists have strengths and limitations in relation to clinical, business, and employability knowledge and skills. New graduate work-readiness and transition may be enhanced by additional private practice experience, employer and client expectation management, provision of workplace support, and tailored university and continuing education.

IMPACT: The number of new graduate physical therapists employed in private practice in Australia is increasing; however, until this study, their work-readiness for this setting was unknown. This exploration of new graduate performance in private practice and transition can help to increase understanding and enhancement of work-readiness.

PMID:33686439 | DOI:10.1093/ptj/pzab078

Z Erziehwiss. 2021 Mar 3:1-17. doi: 10.1007/s11618-021-01001-y. Online ahead of print.

ABSTRACT

Keeping schools open was an active strategy in Sweden to meet the threats of the COVID-19 pandemic. In this article we analyze how a collection of welfare state agents with different tasks, resources and interests in interaction formed an assemblage in their responses to the pandemic and how education thereby became part of a strategy to keep the society going. The inquiries concern what this tells us about education as framed and constrained as a part of society. Our observations are based on statements presented by the government and public agencies, mass media and websites. We identified an assemblage of interwoven agents such as institutions, laws, regulations and recommendations, pandemic manuals, statistics and media. All these were brought together by actions and ideas to handle a pandemic when there were no preventive vaccines. The overarching principle was to educate the population to competent actions in dealing with the pandemic. To keep schools open was part of that principle combined with caretaking ambitions. This assemblage looked like a centralistic machine but it was not; risks were pushed back to local authorities and schools. In conclusion, we note that education is vital in the overarching strategy to deal with the pandemic in Sweden in terms of trust in people and governmentality.

PMID:33686342 | PMC:PMC7927774 | DOI:10.1007/s11618-021-01001-y

Nat Hum Behav. 2021 Mar 8. doi: 10.1038/s41562-021-01065-0. Online ahead of print.

ABSTRACT

How do we evaluate a group of people after a few negative experiences with some members but mostly positive experiences otherwise? How do rare experiences influence our overall impression? We show that rare events may be overweighted due to normative inference of the hidden causes that are believed to generate the observed events. We propose a Bayesian inference model that organizes environmental statistics by combining similar events and separating outlying observations. Relying on the model’s inferred latent causes for group evaluation overweights rare or variable events. We tested the model’s predictions in eight experiments where participants observed a sequence of social or non-social behaviours and estimated their average. As predicted, estimates were biased toward sparse events when estimating after seeing all observations, but not when tracking a summary value as observations accrued. Our results suggest that biases in evaluation may arise from inferring the hidden causes of group members’ behaviours.

PMID:33686201 | DOI:10.1038/s41562-021-01065-0

Eye (Lond). 2021 Mar 8. doi: 10.1038/s41433-021-01490-5. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate the inter-rater reliability for identification of complete retinal pigment epithelium and outer retinal atrophy (cRORA) on SD-OCT images as defined by the Classification of Atrophy Meetings (CAM) group.

METHODS: Fifty images of anonymized SD-OCT line scans of eyes with cRORA due to AMD were selected. Each .tiff image was saved in both black-on-white (BW) and white-on-black (WB) format. Five retina-trained clinicians graded both sets of images twice for the diagnosis of cRORA based on the CAM group definition. Fleiss kappa statistic was calculated for inter-rater reliability and Cohen’s kappa statistic for intra-grader and inter-grader reliability between any two graders.

RESULTS: The inter-grader reliability varied from as low as 0.28 to 0.92 for WB images and 0.34 to 0.86 for BW images. However, the inter-grader and intra-grader agreement was ĸ WB 0.92; ĸ BW 0.86 and ĸ 0.92 respectively, for graders accustomed to the CAM criteria. Fleiss kappa was ĸ 0.49 (p value < 0.0001) for WB images and ĸ 0.34 (p value < 0.0001 for BW images. Overall, the agreement was better using WB images for all parameters except RPE attenuation/loss.

CONCLUSION: There is significant variability in diagnosis of cRORA on SD-OCT by retina-trained ophthalmologists in the real world. The study highlights the need for training to recognise the different features of cRORA prior to its implementation in clinical practice.

PMID:33686233 | DOI:10.1038/s41433-021-01490-5

Nat Genet. 2021 Mar 8. doi: 10.1038/s41588-021-00787-1. Online ahead of print.

ABSTRACT

Psychiatric disorders are highly genetically correlated, but little research has been conducted on the genetic differences between disorders. We developed a new method (case-case genome-wide association study; CC-GWAS) to test for differences in allele frequency between cases of two disorders using summary statistics from the respective case-control GWAS, transcending current methods that require individual-level data. Simulations and analytical computations confirm that CC-GWAS is well powered with effective control of type I error. We applied CC-GWAS to publicly available summary statistics for schizophrenia, bipolar disorder, major depressive disorder and five other psychiatric disorders. CC-GWAS identified 196 independent case-case loci, including 72 CC-GWAS-specific loci that were not significant at the genome-wide level in the input case-control summary statistics; two of the CC-GWAS-specific loci implicate the genes KLF6 and KLF16 (from the Krüppel-like family of transcription factors), which have been linked to neurite outgrowth and axon regeneration. CC-GWAS loci replicated convincingly in applications to datasets with independent replication data.

PMID:33686288 | DOI:10.1038/s41588-021-00787-1

Nat Hum Behav. 2021 Mar 8. doi: 10.1038/s41562-021-01053-4. Online ahead of print.

ABSTRACT

Epidemiological studies show high comorbidity between different mental health problems, indicating that individuals with a diagnosis of one disorder are more likely to develop other mental health problems. Genetic studies reveal substantial sharing of genetic factors across mental health traits. However, mental health is also genetically correlated with socio-economic status (SES), and it is therefore important to investigate and disentangle the genetic relationship between mental health and SES. We used summary statistics from large genome-wide association studies (average N ~ 160,000) to estimate the genetic overlap across nine psychiatric disorders and seven substance use traits and explored the genetic influence of three different indicators of SES. Using genomic structural equation modelling, we show significant changes in patterns of genetic correlations after partialling out SES-associated genetic variation. Our approach allows the separation of disease-specific genetic variation and genetic variation shared with SES, thereby improving our understanding of the genetic architecture of mental health.

PMID:33686200 | DOI:10.1038/s41562-021-01053-4

Sci Rep. 2021 Mar 8;11(1):5355. doi: 10.1038/s41598-021-84486-1.

ABSTRACT

The homological scaffold leverages persistent homology to construct a topologically sound summary of a weighted network. However, its crucial dependency on the choice of representative cycles hinders the ability to trace back global features onto individual network components, unless one provides a principled way to make such a choice. In this paper, we apply recent advances in the computation of minimal homology bases to introduce a quasi-canonical version of the scaffold, called minimal, and employ it to analyze data both real and in silico. At the same time, we verify that, statistically, the standard scaffold is a good proxy of the minimal one for sufficiently complex networks.

PMID:33686171 | DOI:10.1038/s41598-021-84486-1

Sci Rep. 2021 Mar 8;11(1):5440. doi: 10.1038/s41598-021-84844-z.

ABSTRACT

In grasses, leaf expansion and central rib growth occur in a non-proportional manner, with potential implications to the nutritive value of leaves. The objective of this study was to evaluate the relationship among blade length, percentage of central rib, anatomical characteristics and the nutritive value along the length of leaf blades of different sizes and hierarchical order of insertion on the tiller axis of Napier elephant grass (Pennisetum purpureum Schum. cv. Napier). Two experiments were carried out with isolated growing plants during the summer of 2017 (January to March). Central rib mass increased linearly with the increase in leaf blade mass and its percentage relative to blade mass decreased from the base to the tip of the leaf. There were no significant variations in anatomical characteristics along the length of leaf blades when central rib was not taken into account. The central rib showed negative relationship with nutritive value. The apical portions of long leaves showed similar digestibility to short leaves. The multivariate analysis of Cluster and Principal Components grouped the response variables according to leaf hierarchical order, final blade length and percentage of structural tissues, highlighting the relationship between leaf size, structural tissues and nutritive value.

PMID:33686178 | DOI:10.1038/s41598-021-84844-z

Sci Rep. 2021 Mar 8;11(1):5356. doi: 10.1038/s41598-021-85082-z.

ABSTRACT

Partial hepatectomy (PHx) is the gold standard for the treatment of colorectal cancer liver metastases. However, after removing a substantial amount of hepatic tissue, growth factors are released to induce liver regeneration, which may promote the proliferation of liver micrometastases or circulating tumour cells still present in the patient. The aim of this study is to assess the effect of PHx on the growth of liver metastases induced by intrasplenic cell inoculation as well as on in vitro proliferation of the same cancer cell line. Liver tumours were induced in 18 WAG/RijHsd male rats, by seeding 250,000 syngeneic colorectal cancer cells (CC531) into the spleen. The left lateral lobe of the liver was mobilized and in half of the animals it was removed to achieve a 40% hepatectomy. Twenty-eight days after tumour induction, the animals were sacrificed and the liver was removed and sliced to assess the relative tumour surface area (RTSA%). CC531 cells were cultured in presence of foetal calf serum, non-hepatectomised (NRS) or hepatectomized rat serum (HRS), and their proliferation rate at 24, 48, and 72 h was measured. RTSA% was significantly higher in animals which had undergone PHx than in the controls (non-hepatectomised) (46.98 ± 8.76% vs. 18.73 ± 5.65%; p < 0.05). Analysing each lobe separately, this difference in favour of hepatectomized animals was relevant and statistically significant in the paramedian and caudate lobes. But in the right lobe the difference was scarce and not significant. In vitro, 2.5% HRS achieved stronger proliferative rates than the control cultures (10% FCS) or their equivalent of NRS. In this experimental model, a parallelism has been shown between the effect of PHx on the growth of colorectal cancer cells in the liver and the effect of the serum on those cells in vitro.

PMID:33686132 | DOI:10.1038/s41598-021-85082-z