Realist Review: Current Practice and Future Prospects

Realist review has emerged as a specific literature review approach that is concerned with explaining the outcomes of complex intervention programs. We undertook a systematic scoping review to examine the current practice of realist review. A systematic scoping review is a process of mapping the existing evidence base on a particular topic. We identified a growing body of literature using the realist review approach. We selected 54 reviews for our study. These reviews covered a range of topics, including health care, education, management, and public safety. We found that the initial process of exploratory scoping of the literature was described in only 58 per cent of the reviews. The approaches regarding appraisal, analysis, and synthesis of the selected studies were poorly described in most reviews. Overall, there was little uniformity and transparency regarding many methodological issues. Specific methodological guidance may need to be developed if realist reviews are to have a more uniform and transparent approach

The Science Performance of JWST as Characterized in Commissioning

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb29

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Realist Review: Current Practice and Future Prospects

Realist review has emerged as a specific literature review approach that is concerned with explaining the outcomes of complex intervention programs. We undertook a systematic scoping review to examine the current practice of realist review. A systematic scoping review is a process of mapping the existing evidence base on a particular topic. We identified a growing body of literature using the realist review approach. We selected 54 reviews for our study. These reviews covered a range of topics, including health care, education, management, and public safety. We found that the initial process of exploratory scoping of the literature was described in only 58 per cent of the reviews. The approaches regarding appraisal, analysis, and synthesis of the selected studies were poorly described in most reviews. Overall, there was little uniformity and transparency regarding many methodological issues. Specific methodological guidance may need to be developed if realist reviews are to have a more uniform and transparent approach

Women Who Trade Sexual Services from Men: A Systematic Mapping Review

Most research on transactional sex frame men as buyers and females as sellers of sex. We conducted a systematic mapping review of the empirical research on transactional sex where women form the demand (buyer) and men the supply (seller). We included 46 studies, of which 25 explicitly researched women as buyers of sex from male sellers, and 21 studies where this topic was a subset of larger topics. The majority of research on women who trade sexual services from men is published in the last 15 years, by female researchers, using cross-sectional or qualitative/ethnographic design, and from the perspective of males as sellers. While the women appear to be mature and financially independent, the men are young and socioeconomically vulnerable. Men’s main motivation for the sexual-economic exchanges with women is financial, whereas women’s motivations are largely satisfaction of sexual needs and a stereotyped erotic fantasy of black male hypersexuality. Condoms are often not used. Our review shows that there is a – possibly growing and diversifying – female consumer demand for male sexual services, and transactional sex where women trade sex from men is a complex social phenomenon firmly grounded in social, economic, political, and sexual relations

Dietary Alteration of the Gut Microbiome and Its Impact on Weight and Fat Mass: A Systematic Review and Meta-Analysis

Dietary alteration of the gut microbiome is an important target in the treatment of obesity. Animal and human studies have shown bidirectional weight modulation based on the probiotic formulation used. In this study, we systematically reviewed the literature and performed a meta-analysis to assess the impact of prebiotics, probiotics and synbiotics on body weight, body mass index (BMI) and fat mass in adult human subjects. We searched Medline (PubMed), Embase, the Cochrane Library and the Web of Science to identify 4721 articles, of which 41 were subjected to full-text screening, yielding 21 included studies with 33 study arms. Probiotic use was associated with significant decreases in BMI, weight and fat mass. Studies of subjects consuming prebiotics demonstrated a significant reduction in body weight, whereas synbiotics did not show an effect. Overall, when the utilization of gut microbiome-modulating dietary agents (prebiotic/probiotic/synbiotic) was compared to placebo, there were significant decreases in BMI, weight and fat mass. In summary, dietary agents for the modulation of the gut microbiome are essential tools in the treatment of obesity and can lead to significant decreases in BMI, weight and fat mass. Further studies are needed to identify the ideal dose and duration of supplementation and to assess the durability of this effect

A Meta-Analysis of fMRI Studies of Youth Cannabis Use: Alterations in Executive Control, Social Cognition/Emotion Processing, and Reward Processing in Cannabis Using Youth

Background: Adolescent cannabis use (CU) is associated with adverse health outcomes and may be increasing in response to changing cannabis laws. Recent imaging studies have identified differences in brain activity between adult CU and controls that are more prominent in early onset users. Whether these differences are present in adolescent CU and relate to age/developmental stage, sex, or cannabis exposure is unknown. Methods: A systematic review and subsequent effect-size seed-based d mapping (SDM) meta-analysis were conducted to examine differences in blood-oxygen-level-dependent (BOLD) response during fMRI studies between CU and non-using typically developing (TD) youth. Supplemental analyses investigated differences in BOLD signal in CU and TD youth as a function of sex, psychiatric comorbidity, and the dose and severity of cannabis exposure. Results: From 1371 citations, 45 fMRI studies were identified for inclusion in the SDM meta-analysis. These studies compared BOLD response contrasts in 1216 CU and 1486 non-using TD participants. In primary meta-analyses stratified by cognitive paradigms, CU (compared to TD) youth showed greater activation in the rostral medial prefrontal cortex (rmPFC) and decreased activation in the dorsal mPFC (dmPFC) and dorsal anterior cingulate cortex (dACC) during executive control and social cognition/emotion processing, respectively. In meta-regression analyses and subgroup meta-analyses, sex, cannabis use disorder (CUD) severity, and psychiatric comorbidity were correlated with brain activation differences between CU and TD youth in mPFC and insular cortical regions. Activation differences in the caudate, thalamus, insula, dmPFC/dACC, and precentral and postcentral gyri varied as a function of the length of abstinence. Conclusions: Using an SDM meta-analytic approach, this report identified differences in neuronal response between CU and TD youth during executive control, emotion processing, and reward processing in cortical and subcortical brain regions that varied as a function of sex, CUD severity, psychiatric comorbidity, and length of abstinence. Whether aberrant brain function in CU youth is attributable to common predispositional factors, cannabis-induced neuroadaptive changes, or both warrants further investigation