We have attempted to quantify the frequency and effects of slightly deleterious mutations (SDMs), those that have selective effects close to the reciprocal of the effective population size of a species, by comparing the level of selective constraint in protein-coding genes of related species that have different present-day effective population sizes. In our two comparisons, the species with the smaller effective population size showed lower constraint, implying that SDMs had become fixed. The fixation of SDMs was supported by the observation of a higher fraction of radical to conservative amino acid substitutions in species with smaller effective population sizes. The fraction of strongly deleterious mutations (which rarely become fixed) is >70% in most species. Only approximately 10% or fewer of mutations seem to behave as SDMs, but SDMs could comprise a substantial fraction of mutations in protein-coding genes that have a chance of becoming fixed between species.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1093/oxfordjournals.molbev.a004039 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Neural effects of memory training to reduce false memories in older adults: Univariate and multivariate analyses.
Neurobiol Aging
January 2025
Department of Psychology, The Pennsylvania State University, University Park, PA 16802, United States. Electronic address:
The growing population of older adults emphasizes the need to develop interventions that prevent or delay some of the cognitive decline that accompanies aging. In particular, as memory impairment is the foremost cognitive deficit affecting older adults, it is vital to develop interventions that improve memory function. This study addressed the problem of false memories in aging by training older adults to use details of past events during memory retrieval to distinguish targets from related lures.
View Article and Find Full Text PDFPerson-Specific Analyses of Smartphone Use and Mental Health: An Intensive Longitudinal Study Over One Year.
JMIR Form Res
December 2024
Department of Communication, Stanford University, Stanford, US.
Background: Contrary to popular concerns about the harmful effects of media use on mental health, research on this relationship is ambiguous, stalling advances in theory, interventions, and policy. Scientific explorations of the relationship between media and mental health have mostly found null or small associations, with the results often blamed on the use of cross-sectional study designs or imprecise measures of media use and mental health.
Objective: This exploratory empirical demonstration aimed to answer whether mental health effects are associated with media use experiences by (1) redirecting research investments to granular and intensive longitudinal recordings of digital experiences to build models of media use and mental health for single individuals over the course of one entire year, (2) using new metrics of fragmented media use to propose explanations of mental health effects that will advance person-specific theorizing in media psychology, and (3) identifying combinations of media behaviors and mental health symptoms that may be more useful for studying media effects than single measures of dosage and affect or assessments of clinical symptoms related to specific disorders.
Adjuvant transarterial chemoembolization for hepatocellular carcinoma following curative resection: A randomized, open-label, phase 3 trial.
Hepatology
January 2025
Department of Hepatobiliary and Pancreatic Surgery, the First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.
Background Aims: The role of adjuvant transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) following curative resection remains controversial. We aimed to determine the effectiveness of postoperative adjuvant TACE in HCC patients.
Approach Results: In this randomized phase 3 trial, histologically confirmed HCC patients (AJCC TNM stage I and II) were randomly assigned (1:1) to adjuvant TACE or observation groups.
Methodological Considerations When Studying Resistance-Trained Populations: Ideas for Using Control Groups.
J Strength Cond Res
December 2024
Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, University, Mississippi; and.
Hammert, WB, Dankel, SJ, Kataoka, R, Yamada, Y, Kassiano, W, Song, JS, and Loenneke, JP. Methodological considerations when studying resistance-trained populations: Ideas for using control groups. J Strength Cond Res 38(12): 2164-2171, 2024-The applicability of training effects from experimental research depends on the ability to quantify the degree of measurement error accurately over time, which can be accounted for by including a time-matched nonexercise control group.
View Article and Find Full Text PDFBackground: Nephrology has seen an uptake in transition to remote care delivery. The impact of telenephrology care on chronic kidney disease (CKD) progression is not well defined.
Methods: We analyzed data from patients naturally selected for telenephrology versus standard, in-person visits.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!