scholarly journals A new workflow combining R packages for statistical analysis of metabolites

2019 ◽  
Author(s):  
Paola G. Ferrario
Keyword(s):  
Statistical Analysis ◽  
Large Scale ◽  
Research Question ◽  
Central Research ◽  
Metabolomics Data ◽  
Large Scale Study ◽  
Public Data ◽  
R Packages

AbstractIn metabolomics, the investigation of an association between many metabolites and one trait (such as age in humans or cultivar in foods) is a central research question. On this topic, we present a complete statistical analysis, combining selected R packages in a new workflow, which we are sharing completely, according to modern standards and research reproducibility requirements. We demonstrate the workflow using a large-scale study with public data, available on repositories. Hence, the workflow can directly be re-used on quite different metabolomics data, when searching for association with one covariate of interest.

THE NEEDS AND EXPECTATIONS OF STAFF AND STUDENTS LIVING WITH HIV AND AIDS IN A SOUTH AFRICA RURAL-BASED UNIVERSITY

2015 ◽  
Vol 16 (2) ◽  
pp. 30-43
Author(s):  
Azwihangwisi Mavhandu-Mudzusi
Keyword(s):  
South African ◽  
Large Scale ◽  
Research Question ◽  
Qualitative Interviews ◽  
Hiv And Aids ◽  
Central Research ◽  
Immunodeficiency Syndrome ◽  
Living With Hiv ◽  
The Impact ◽  
Hiv Aids

Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) are making an impact in institutions of higher education. Studies have revealed that though few students and staff have been recorded to be suffering from HIV/AIDS, more have become ill and some have died in ways that signal the impact of HIV/AIDS. Universities can contribute to addressing the needs and expectations of staff and students living with HIV and AIDS. The purpose of this study was to explore and describe the preparedness of a South African rural-based university in addressing the needs and expectations of staff and students living with HIV and AIDS. A qualitative study design was followed, with one South African rural-based university as the case setting. Qualitative interviews were conducted stemming from the central research question, “How is the university addressing the needs and expectations of staff and students living with HIV and AIDS?” Following an open coding method of data analysis, three themes emerged relating to how the needs and expectations of staff and students living with HIV and AIDS are addressed: persistence stigma and discrimination, limited assurance to confidentiality and, inadequate treatment, care and support. Recommendations were made for improvement of service delivery to address the needs and expectations of staff and students living with HIV and AIDS and further research should be conducted on large scale to determine other needs and expectations of SSLWHA other South African rural-based universities and how they are addressed.

scholarly journals Processos híbridos e a influência das tecnologias digitais nas práticas artísticas

2019 ◽  
Vol 24 (40) ◽  
Author(s):  
Alessandra Lucia Bochio ◽  
Marina Bortoluz Polidoro
Keyword(s):  
Large Scale ◽  
Research Question ◽  
Digital Technologies ◽  
The Other ◽  
Central Research ◽  
Daily Lives ◽  
Other Hand ◽  
The One ◽  
The Way ◽  
New Look

O artigo apresenta uma reflexão acerca da produção de imagens em um contexto pós-digital, abordando a influência das tecnologias digitais em práticas artísticas artesanais. Por um lado, as produções em arte desde a modernidade têm evidenciado sobreposição de procedimentos e técnicas, apropriações, ampliação das linguagens e hibridismos. Por outro lado, a popularização das tecnologias digitais e a incorporação dessas em larga escala faz com que a presença das mesmas em etapas nos processos artísticos aconteça de forma naturalizada, mesmo naqueles que não têm as tecnologias como questão central de investigação. Conclui-se que as mudanças ocorridas por meio da naturalização das tecnologias digitais em nosso cotidiano e a forma como estas estão nos afetando atualmente, oferecem um novo olhar às estratégias utilizadas pelos artistas e colocam ainda novos problemas a eles.Abstract The article presents a reflection about the production of images in a post-digital context, addressing the influence of digital technologies on artisanal artistic practices. On the one hand, the productions in art since the modernity have evidenced overlapping of procedures and techniques, appropriations, amplification of languages and hybridity. On the other hand, the popularization of digital technologies and the incorporation of these on a large scale makes their presence in stages in the artistic processes happen in a naturalized way, even in those which do not hold the technologies as a central research question. We conclude that the changes that have taken place through the naturalization of digital technologies in our daily lives, and the way they are currently affecting us, offer a new look at the strategies used by artists and pose new problems for them.

scholarly journals What we eval in the shadows: a large-scale study of eval in R programs

2021 ◽  
Vol 5 (OOPSLA) ◽  
pp. 1-23
Author(s):  
Aviral Goel ◽  
Pierre Donat-Bouillud ◽  
Filip Křikava ◽  
Christoph M. Kirsch ◽  
Jan Vitek
Keyword(s):  
Static Analysis ◽  
Large Scale ◽  
Data Science ◽  
Negative Impact ◽  
Application Domain ◽  
Domain Specific ◽  
Web Programming ◽  
Large Scale Study ◽  
Dynamic Languages ◽  
R Packages

Most dynamic languages allow users to turn text into code using various functions, often named <tt>eval</tt>, with language-dependent semantics. The widespread use of these reflective functions hinders static analysis and prevents compilers from performing optimizations. This paper aims to provide a better sense of why programmers use <tt>eval</tt>. Understanding why <tt>eval</tt> is used in practice is key to finding ways to mitigate its negative impact. We have reasons to believe that reflective feature usage is language and application domain-specific; we focus on data science code written in R and compare our results to previous work that analyzed web programming in JavaScript. We analyze 49,296,059 calls to <tt>eval</tt> from 240,327 scripts extracted from 15,401 R packages. We find that <tt>eval</tt> is indeed in widespread use; R’s <tt>eval</tt> is more pervasive and arguably dangerous than what was previously reported for JavaScript.

scholarly journals Large-scale study of Toxoplasma and Cytomegalovirus shows an association between infection and serious psychiatric disorders

2019 ◽  
Vol 79 ◽  
pp. 152-158 ◽  
Author(s):  
Kristoffer Sølvsten Burgdorf ◽  
Betina B. Trabjerg ◽  
Marianne Giørtz Pedersen ◽  
Janna Nissen ◽  
Karina Banasik ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Large Scale ◽  
Large Scale Study

scholarly journals Measuring sleep regularity: Theoretical properties and practical usage of existing metrics

SLEEP ◽  
2021 ◽  
Author(s):  
Dorothee Fischer ◽  
Elizabeth B Klerman ◽  
Andrew J K Phillips
Keyword(s):  
Large Scale ◽  
Research Question ◽  
Group Differences ◽  
Regularity Index ◽  
Wake Patterns ◽  
Health Related ◽  
Phase Deviation ◽  
Unbiased Estimates ◽  
Large Scale Simulations ◽  
Larger Sample

Abstract Study Objectives Sleep regularity predicts many health-related outcomes. Currently, however, there is no systematic approach to measuring sleep regularity. Traditionally, metrics have assessed deviations in sleep patterns from an individual’s average. Traditional metrics include intra-individual standard deviation (StDev), Interdaily Stability (IS), and Social Jet Lag (SJL). Two metrics were recently proposed that instead measure variability between consecutive days: Composite Phase Deviation (CPD) and Sleep Regularity Index (SRI). Using large-scale simulations, we investigated the theoretical properties of these five metrics. Methods Multiple sleep-wake patterns were systematically simulated, including variability in daily sleep timing and/or duration. Average estimates and 95% confidence intervals were calculated for six scenarios that affect measurement of sleep regularity: ‘scrambling’ the order of days; daily vs. weekly variation; naps; awakenings; ‘all-nighters’; and length of study. Results SJL measured weekly but not daily changes. Scrambling did not affect StDev or IS, but did affect CPD and SRI; these metrics, therefore, measure sleep regularity on multi-day and day-to-day timescales, respectively. StDev and CPD did not capture sleep fragmentation. IS and SRI behaved similarly in response to naps and awakenings but differed markedly for all-nighters. StDev and IS required over a week of sleep-wake data for unbiased estimates, whereas CPD and SRI required larger sample sizes to detect group differences. Conclusions Deciding which sleep regularity metric is most appropriate for a given study depends on a combination of the type of data gathered, the study length and sample size, and which aspects of sleep regularity are most pertinent to the research question.

Isolation, Characterization, and Differentiation of Stem Cells From Various Dental Sources: An In Vitro Study

2021 ◽  
pp. 232020682110107
Author(s):  
Sandeep S. Katti ◽  
Kishore Bhat ◽  
Chetana Bogar
Keyword(s):  
Stem Cells ◽  
Growth Factors ◽  
Statistical Analysis ◽  
Specific Growth ◽  
Culture Media ◽  
In Vitro Study ◽  
Central Research ◽  
Cell Lineages ◽  
Apical Papilla

Aim: The aim of the current study was to isolate stem cells from various dental sources such as dental pulp, periodontal ligament (PDL), and apical papilla, and to characterize stem cells by staining for the presence/absence of specific surface markers and also to differentiate stem cells into osteogenic, chondrogenic, and adipogenic cell lineages by exposing them to specific growth factors under the ideal conditions. Materials and Methods: A total of 117 samples were included in the study, consisting of 30 pulp, 50 gingival, 35 PDL, and 2 apical papilla samples. The pulp was extirpated and transported to the Central Research Laboratory. Gingival connective tissue was collected from the participants undergoing any crown lengthening procedure or any gingivectomy procedure from the Department of Periodontology. A similar procedure was also followed for apical papilla and PDL. Isolation was done followed by the identification of the cells by immunocytochemistry using different markers. Once the identity of cells was confirmed, these cells were treated with different culture media to attain 70% to 100% confluency. Then the medium was replaced with a conditioning medium containing specific growth factors for differentiation into osteogenic, chondrogenic, and adipogenic cell lineages. Result: In our study, the number of samples collected and processed was 117. The isolation rate of stem cells from the above-collected samples was 70%. Statistical analysis—no statistical analysis was done as there was no variability expected. Conclusion: Our study showed that stem cells could be isolated, differentiated, and characterized from different dental sources.

scholarly journals Correction to: Methane and Electricity Production from Poultry Litter Digestion in the Amazon Region of Brazil: A Large-Scale Study

2021 ◽  
Author(s):  
Marcelo Mendes Pedroza ◽  
Wanderson Gomes da Silva ◽  
Luciene Santos de Carvalho ◽  
Alice Rocha de Souza ◽  
Girlene Figueiredo Maciel
Keyword(s):  
Large Scale ◽  
Poultry Litter ◽  
Amazon Region ◽  
Electricity Production ◽  
Large Scale Study
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