scholarly journals Frugivore gut passage increases seed germination: an updated meta-analysis

2021 ◽  
Author(s):  
Haldre S Rogers ◽  
Brittany R Cavazos ◽  
Ann Marie Gawel ◽  
Alex T Karnish ◽  
Courtenay A Ray ◽  
...  

Many plants rely on animal mutualists for reproduction. Quantifying how animal mutualists impact plant performance provides a foundation for modelling how change in animal communities affects the composition and functioning of plant communities. We performed a meta-analysis of 2539 experiments, 6 times more than the last comprehensive meta-analysis, examining how gut passage by frugivores influences seed germination. We simultaneously analyzed multiple predictor variables related to study methodology, location, and frugivore identity to disentangle methodological from ecological impacts on effect sizes. We found that gut passage by birds, fish, reptiles, bats, primates, and other mammals on average increased seed germination, but that the magnitude varied across vertebrate groups. The positive effects of gut passage were largely explained by the de-inhibitory effects of pulp removal rather than by the scarification of seed tissues. Some previous studies and meta-analyses that found no effect of gut passage only tested scarification or did not distinguish between these tests of scarification and pulp removal. We found that, for a typical fleshy-fruited plant species, the lack of gut passage reduces germination by 60%. From an evolutionary perspective, this indicates a large risk associated with reliance on animal mutualists that is balanced against the benefits of animal-mediated seed dispersal. From a conservation perspective, this highlights the potential for large demographic consequences of frugivore declines on plant populations. Our database and findings advance quantitative predictions for the role of fruit-frugivore interactions in shaping plant communities in the Anthropocene.

2021 ◽  
pp. 003435522110432
Author(s):  
Areum Han

Objective: Mindfulness- and acceptance-based intervention (MABI) is an emerging evidenced-based practice, but no systematic review incorporating meta-analyses for MABIs in stroke survivors has been conducted. The objective of this systematic review was to measure the effectiveness of MABIs on outcomes in people with stroke. Method: Three electronic databases, including PubMed, CINAHL, and PsycINFO, were searched to identify relevant studies published in peer-reviewed journals. The methodological quality of the included studies was assessed. Data were extracted and combined in a meta-analysis with a random-effect model to compute the size of the intervention effect. Results: A total of 11 studies met the eligibility criteria. Meta-analyses found a small-to-moderate effect of MABIs on depressive symptoms (standardized mean difference [SMD] = 0.39, 95% confidence interval [CI] = [0.12, 0.66]) and a large effect on mental fatigue (SMD = 1.22, 95% CI = [0.57, 1.87]). No statistically significant effect of MABIs on anxiety, quality of life, and mindfulness was found, but there was a trend in favor of MABIs overall. Conclusions: This meta-analysis found positive effects of MABIs on depressive symptoms and mental fatigue in stroke survivors, but future high-quality studies are needed to guarantee treatment effects of MABIs on varied outcomes in stroke survivors.


2018 ◽  
Vol 115 (24) ◽  
pp. 6237-6242 ◽  
Author(s):  
Shihong Jia ◽  
Xugao Wang ◽  
Zuoqiang Yuan ◽  
Fei Lin ◽  
Ji Ye ◽  
...  

The theory of “top-down” ecological regulation predicts that herbivory suppresses plant abundance, biomass, and survival but increases diversity through the disproportionate consumption of dominant species, which inhibits competitive exclusion. To date, these outcomes have been clear in aquatic ecosystems but not on land. We explicate this discrepancy using a meta-analysis of experimental results from 123 native animal exclusions in natural terrestrial ecosystems (623 pairwise comparisons). Consistent with top-down predictions, we found that herbivores significantly reduced plant abundance, biomass, survival, and reproduction (allP< 0.01) and increased species evenness but not richness (P= 0.06 andP= 0.59, respectively). However, when examining patterns in the strength of top-down effects, with few exceptions, we were unable to detect significantly different effect sizes among biomes, based on local site characteristics (climate or productivity) or study characteristics (study duration or exclosure size). The positive effects on diversity were only significant in studies excluding large animals or located in temperate grasslands. The results demonstrate that top-down regulation by herbivores is a pervasive process shaping terrestrial plant communities at the global scale, but its strength is highly site specific and not predicted by basic site conditions. We suggest that including herbivore densities as a covariate in future exclosure studies will facilitate the discovery of unresolved macroecology trends in the strength of herbivore–plant interactions.


2019 ◽  
Vol 16 (12) ◽  
pp. 1187-1195
Author(s):  
Nathanial J. Kapsal ◽  
Theresa Dicke ◽  
Alexandre J.S. Morin ◽  
Diego Vasconcellos ◽  
Christophe Maïano ◽  
...  

Background: The physical and psychosocial benefits of physical activity for typically developing youth are well established; however, its impact on youth with intellectual disabilities is not as well understood. The aims of this review and meta-analysis were to synthesize the literature and quantify the effects of physical activity on the physical and psychosocial health of youth with intellectual disabilities. Method: Studies meeting the inclusion criteria were grouped by their focus on physical health and/or psychosocial health outcomes. Meta-analyses were performed using 3-level, random effects and mixed effects models. Results: One hundred nine studies met the inclusion criteria. Physical activity had a large effect on physical health (g = 0.773, P < .001) and a moderately large effect (g = 0.682, P < .001) on psychosocial health. Participant age, intellectual disability level, other developmental disabilities, outcome type, and intervention type moderated the effects of physical activity on physical health, whereas study design, risk of bias, other developmental disabilities, outcome type, and intervention type were moderators on psychosocial health. Conclusions: Physical activity has positive effects on the physical and psychosocial health of youth with intellectual disabilities. Although resistance training shows the most physical benefits, teaching movement and sports skills appear to benefit their physical and psychosocial health.


2008 ◽  
Vol 65 (3) ◽  
pp. 437-447 ◽  
Author(s):  
Tim J Haxton ◽  
C Scott Findlay

Systematic meta-analyses were conducted on the ecological impacts of water management, including effects of (i) dewatering on macroinvertebrates, (ii) a hypolimnetic release on downstream aquatic fish and macro invertebrate communities, and (iii) flow modification on fluvial and habitat generalists. Our meta-analysis indicates, in general, that (i) macroinvertebrate abundance is lower in zones or areas that have been dewatered as a result of water fluctuations or low flows (overall effect size, –1.64; 95% confidence intervals (CIs), –2.51, –0.77), (ii) hypolimnetic draws are associated with reduced abundance of aquatic (fish and macroinvertebrates) communities (overall effect size, –0.84; 95% CIs, –1.38, –0.33) and macroinvertebrates (overall effect size, –0.73; 95% CIs, –1.24, –0.22) downstream of a dam, and (iii) altered flows are associated with reduced abundance of fluvial specialists (–0.42; 95% CIs, –0.81, –0.02) but not habitat generalists (overall effect size, –0.14; 95% CIs, –0.61, 0.32). Publication bias is evident in several of the meta-analyses; however, multiple experiments from a single study may be contributing to this bias. Fail-safe Ns suggest that many (>100) studies showing positive or no effects of water management on the selected endpoints would be required to qualitatively change the results of the meta-analysis, which in turn suggests that the conclusions are reasonably robust.


2006 ◽  
Vol 76 (2) ◽  
pp. 275-313 ◽  
Author(s):  
Patricia A. Lauer ◽  
Motoko Akiba ◽  
Stephanie B. Wilkerson ◽  
Helen S. Apthorp ◽  
David Snow ◽  
...  

Schools and districts are adopting out-of-school-time (OST) programs such as after-school programs and summer schools to supplement the education of low-achieving students. However, research has painted a mixed picture of their effectiveness. To clarify OST impacts, this synthesis examined research on OST programs for assisting at-risk students in reading and/or mathematics. Researchers analyzed 35 OST studies that employed control or comparison groups and met other inclusion criteria. Meta-analyses indicated small but statistically significant positive effects of OST on both reading and mathematics student achievement and larger positive effect sizes for programs with specific characteristics such as tutoring in reading. Whether the OST program took place after school or during the summer did not make a difference in effectiveness.


2019 ◽  
Author(s):  
Weili Wang ◽  
Kuang-Huei Chen ◽  
Ying-Chieh Pan ◽  
Szu-Nian Yang ◽  
Yuan-Yu Chan

Abstract Objectives To examine the effectiveness and safety of yoga for women with sleep problems by performing a systematic review and meta-analysis.Methods Medline/PubMed, Clincalkey, ScienceDirect, Embase, PsycINFO, and the Cochrane Library were searched throughout the month of June 2019. Randomized controlled trials comparing yoga groups with control groups in women with sleep problems were included. Two reviewers independently evaluated risk of bias by using the risk of bias tool suggested by the Cochrane Collaboration for programming and conducting systematic reviews and meta-analyses. The main outcome measure was sleep quality or the severity of insomnia, which was measured using subjective instruments, such as the Pittsburgh Sleep Quality Index (PSQI), Insomnia severity index (ISI), or objective instruments, such as polysomnography, actigraphy, and safety of the intervention. For each outcome, standardized mean difference (SMD) and 95% confidence intervals (CIs) were determined. Results Nineteen studies including 1832 participants were included in this systematic review. Meta-analyses revealed positive effects of yoga using PSQI or ISI scores in 16 randomized control trials (RCTs) compared with the control group in improving sleep quality in women, PSQI (SMD = −0.54; 95% CI = −0.89 to −0.19 ; P = 0.003). However, three RCTs revealed no effects of yoga compared with the control group in reducing the severity of insomnia in women using ISI (SMD = −0.13; 95% CI = −0.74 to 0.48; P = 0.69). Seven RCTs revealed no evidence for effects of yoga compared with the control group in improving sleep quality for women with breast cancer using PSQI (SMD = −0.15 ; 95% CI = −0.31 to 0.01; P = 0.5). Four RCTs revealed no evidence for the effects of yoga compared with the control group in improving the sleep quality for peri-or postmenopausal women using PSQI (SMD = −0.31; 95% CI = −0.95 to 0.33; P = 0.34).Yoga was not associated with serious adverse events. Discussion This systematic review and meta-analysis found that yoga intervention in some groups of women was beneficial in managing sleep problems. Despite certain disadvantages in methodology in the included studies, yoga may be recommended as a complementary therapy to women.


2021 ◽  
Author(s):  
Peter Carolan ◽  
Antje Heinrich ◽  
Kevin Munro ◽  
Rebecca Millman

Motivation influences the amount of listening effort (LE) exerted or experienced under challenging conditions, such as in high-noise environments. This systematic review and meta-analysis is the first to quantify the effects of motivation on LE. The review was pre-registered in PROSPERO, and performed in accordance with PRISMA guidelines. Eligible studies examined the influence of motivation or individual traits (related to motivation) on LE in adults. Motivational factors, coded as independent variables, included financial reward, evaluative threat, perceived competence, feedback and individual traits. LE outcomes were categorised as subjective, behavioural or physiological. The quality of evidence was assessed using an adaptation of the Cochrane Collaboration Risk of Bias Tool. Nested random-effects meta-analyses were performed to quantify and compare the influence of motivational factors across LE outcomes. After assessing 3532 records, 48 studies met the inclusion criteria and 43 were included in the meta-analyses. Risk of bias was high e.g. many studies lacked sample size justification. Motivational factors had a small-to-medium effect (mean Cohen’s d = 0.34, range: 0.11 – 0.72) on LE. When LE outcomes were considered collectively, an external manipulation of motivation (perceived competence) produced a larger mean effect size compared with individual traits. Some combinations of motivational factors and LE outcomes produced more robust effects than others, e.g. evaluative threat and subjective LE outcomes. Although wide prediction intervals and high risk of bias mean that significant positive effects cannot be guaranteed, these findings provide useful guidance on the selection of motivational factors and LE outcomes for future research.


Oikos ◽  
2016 ◽  
Vol 125 (8) ◽  
pp. 1069-1080 ◽  
Author(s):  
Lisieux F. Fuzessy ◽  
Tatiana G. Cornelissen ◽  
Charles Janson ◽  
Fernando A. O. Silveira

2018 ◽  
Vol 4 (2) ◽  
pp. 153-166 ◽  
Author(s):  
Laura Gough ◽  
David R. Johnson

The interaction between bottom-up and top-down forces in regulating plant communities is a long-standing topic of interest in ecology. Factorial field experiments examining these factors have been relatively few, but recent meta-analyses provide predictions that can be tested in a range of ecosystems. We tested the prediction that added nutrients would reduce species richness and evenness, while herbivore activity would offset those changes in two tundra plant communities after 11 years. In moist acidic tundra (MAT), herbivores reduced richness more in fertilized plots when mammals were present compared with fertilized plots without herbivores. In dry heath (DH), evenness was significantly reduced in fertilized plots only when herbivores were present, also providing evidence that herbivores enhanced community changes caused by greater nutrient availability. The difference in response between MAT and the meta-analysis predictions appears to be driven by Betula nana, the species that dramatically increased with added nutrients in MAT. Unlike in similar studies and in DH, B. nana is not as palatable as most of the species in the community and is generally avoided by herbivores. These results highlight how the effects of herbivory and nutrients differ across communities and can be affected by the traits of the species present.


2020 ◽  
Author(s):  
Weili Wang ◽  
Kuang-Huei Chen ◽  
Ying-Chieh Pan ◽  
Szu-Nian Yang ◽  
Yuan-Yu Chan

Abstract Background: To examine the effectiveness and safety of yoga of women with sleep problems by performing a systematic review and meta-analysis. Methods: Medline/PubMed, ClinicalKey, ScienceDirect, Embase, PsycINFO, and the Cochrane Library were searched throughout the month of June, 2019. Randomized controlled trials comparing yoga groups with control groups in women with sleep problems were included. Two reviewers independently evaluated risk of bias by using the risk of bias tool suggested by the Cochrane Collaboration for programming and conducting systematic reviews and meta-analyses. The main outcome measure was sleep quality or the severity of insomnia, which was measured using subjective instruments, such as the Pittsburgh Sleep QualityIndex (PSQI),Insomnia Severity Index (ISI), or objective instruments such as polysomnography, actigraphy, and safety of the intervention. For each outcome, a standardized mean difference (SMD) and confidence intervals (CIs) of 95% were determined. Results: Nineteen studies in this systematic review included 1832 participants. The meta-analysis of the combined data conducted according to Comprehensive Meta-Analysis showed a significant improvement in sleep (SMD =−0.327, 95% CI=−0.506 to −0.148,P<0.001).Meta-analyses revealed positive effects of yoga using PSQI scores in 16 randomized control trials (RCTs), compared with the control group in improving sleep quality among women usingPSQI (SMD = −0.54; 95% CI = −0.89 to −0.19; P = 0.003). However, three RCTs revealed no effects of yoga compared to the control groupin reducing insomnia among women using ISI (SMD = −0.13; 95% CI = −0.74 to 0.48; P = 0.69).Yoga was not associated with any serious adverse events. Discussion: This systematic review and meta-analysis demonstrated that yoga intervention in women can be beneficial whencompared to non-active control conditions in term of managing sleep problems.The moderator analyses suggest that participants in the non-breast cancer subgroup and participants in the non-peri/postmenopausal subgroup were associated with greater benefits, with a direct correlation of total class time with quality of sleep among other related benefits.


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