scholarly journals Large-scale afforestation for ecosystem service provisioning: learning from the past to improve the future

2021 ◽  
Author(s):  
Ignacio Pérez-Silos ◽  
José Manuel Álvarez-Martínez ◽  
José Barquín
Keyword(s):  
Carbon Sequestration ◽  
Large Scale ◽  
Meta Analysis ◽  
Landscape Management ◽  
Multiple Objectives ◽  
Service Provisioning ◽  
Trade Offs ◽  
Natural Land ◽  
Management Approaches ◽  
Afforestation Policy

Abstract Context Afforestation is one of the major drivers of land cover change in the world. In spite of its multiple applications, forest generation has been fostered during the last century to achieve few specific objectives such as timber production or catchment erosion protection. However, new afforestation programs are required to meet multiple objectives such as carbon sequestration, reducing environmental risks and enhance biodiversity conservation to reach sustainability. Objectives Assessing the general efficiency of past large-scale afforestation programs on the provision of ecosystem services (ES) and other socio-ecological attributes. We also determined whether this efficiency depended on the type of ecosystem used for comparison. Methods We carried out a semi-quantitative meta-analysis from 75 studies analyzing the effects of 128 afforestation actions developed in one of the EU countries with larger areas of afforested land during the twentieth century. Results Spanish afforestation policy improved timber provision and carbon sequestration. However, our results show that afforestation programs did not enhance regulating ES when compared to natural land plots, but only when compared to highly degraded areas prior to restoration actions. Conclusions Large-scale afforestations have difficulties in assuring the provisioning of regulating ES and the conservation of biodiversity when only productivity criteria are prioritized. Our results suggest the need for an afforestation agenda that embraces more comprehensive landscape management approaches that allow reducing undesired ES trade-offs while getting multiple objectives from different ecosystems.

Relationship between total plasma homocysteine and the risk of aneurysms – a meta-analysis

VASA ◽  
2020 ◽  
pp. 1-6
Author(s):  
Hanji Zhang ◽  
Dexin Yin ◽  
Yue Zhao ◽  
Yezhou Li ◽  
Dejiang Yao ◽  
...  
Keyword(s):  
Large Scale ◽  
Meta Analysis ◽  
Single Species ◽  
Total Plasma ◽  
Control Groups ◽  
Randomized Controlled ◽  
Randomized Controlled Studies ◽  
The Difference ◽  
The Relationship ◽  
Healthy Participants

Summary: Our meta-analysis focused on the relationship between homocysteine (Hcy) level and the incidence of aneurysms and looked at the relationship between smoking, hypertension and aneurysms. A systematic literature search of Pubmed, Web of Science, and Embase databases (up to March 31, 2020) resulted in the identification of 19 studies, including 2,629 aneurysm patients and 6,497 healthy participants. Combined analysis of the included studies showed that number of smoking, hypertension and hyperhomocysteinemia (HHcy) in aneurysm patients was higher than that in the control groups, and the total plasma Hcy level in aneurysm patients was also higher. These findings suggest that smoking, hypertension and HHcy may be risk factors for the development and progression of aneurysms. Although the heterogeneity of meta-analysis was significant, it was found that the heterogeneity might come from the difference between race and disease species through subgroup analysis. Large-scale randomized controlled studies of single species and single disease species are needed in the future to supplement the accuracy of the results.

Identification of and Correction for Publication Bias: Comment

2019 ◽  
Author(s):  
Amanda Kvarven ◽  
Eirik Strømland ◽  
Magnus Johannesson
Keyword(s):  
Publication Bias ◽  
False Positive ◽  
Large Scale ◽  
Meta Analysis ◽  
False Positive Rate ◽  
Effect Sizes ◽  
Replication Studies ◽  
Moderate Reduction ◽  
Positive Rate ◽  
Meta Analyses

Andrews & Kasy (2019) propose an approach for adjusting effect sizes in meta-analysis for publication bias. We use the Andrews-Kasy estimator to adjust the result of 15 meta-analyses and compare the adjusted results to 15 large-scale multiple labs replication studies estimating the same effects. The pre-registered replications provide precisely estimated effect sizes, which do not suffer from publication bias. The Andrews-Kasy approach leads to a moderate reduction of the inflated effect sizes in the meta-analyses. However, the approach still overestimates effect sizes by a factor of about two or more and has an estimated false positive rate of between 57% and 100%.

Association between ALDH2 Gene Polymorphism and Late-onset Alzheimer Disease: An Up-to-date Meta-analysis

2020 ◽  
Vol 17 (2) ◽  
pp. 105-111
Author(s):  
Haitao Liu ◽  
Wei Ge ◽  
Wei Chen ◽  
Xue Kong ◽  
Weiming Jian ◽  
...  
Keyword(s):  
Gene Polymorphism ◽  
Large Scale ◽  
Late Onset ◽  
Meta Analysis ◽  
Case Control ◽  
Cochrane Library ◽  
Positive Trend ◽  
Case Control Studies ◽  
China National Knowledge Infrastructure ◽  
Aldh2 Gene

Objectives: Previous case-control studies have focused on the relationship between ALDH2 gene polymorphism and late-onset Alzheimer's Disease (LOAD), but no definite unified conclusion has been reached. Therefore, the correlation between ALDH2 Glu504Lys polymorphism and LOAD remains controversial. To analyze the correlation between ALDH2 polymorphism and the risk of LOAD, we implemented this up-to-date meta-analysis to assess the probable association. Methods: Studies were searched through China National Knowledge Infrastructure (CNKI), VIP Database for Chinese Technical Periodicals, China Biology Medicine, PubMed, Cochrane Library, Clinical- Trials.gov, Embase, and MEDLINE from January 1, 1994 to December 31, 2018, without any restrictions on language and ethnicity. Results: Five studies of 1057 LOAD patients and 1136 healthy controls met our criteria for the analysis. Statistically, the ALDH2 GA/AA genotype was not linked with raising LOAD risk (odds ratio (OR) = 1.48, 95% confidence interval (CI) = 0.96-2.28, p = 0.07). In subgroup analysis, the phenomenon that men with ALDH2*2 had higher risk for LOAD (OR = 1.72, 95%CI = 1.10-2.67, p = 0.02) was observed. Conclusions: This study comprehends only five existing case-control studies and the result is negative. The positive trend might appear when the sample size is enlarged. In the future, more large-scale casecontrol or cohort studies should be done to enhance the association between ALDH2 polymorphism and AD or other neurodegenerative diseases.

Flexible Spectrum Management: Approaches for India

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Arturo Basaure ◽  
Heikki Kokkinen ◽  
Heikki Hämmäinen ◽  
V. Sridhar
Keyword(s):  
Large Scale ◽  
Mobile Services ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Management Approach ◽  
Unlicensed Spectrum ◽  
Spectrum Band ◽  
Management Policies ◽  
Management Approaches ◽  
Lock In

Radio spectrum for commercial mobile services continues to be scarce. Countries around the world have recognized the importance of efficient utilization of this scarce resource and have initiated regulatory and policy steps towards flexible approaches to spectrum management, including sharing of licensed spectrum, and releasing unlicensed spectrum for mobile services. Technologies for shared access and the associated standardization activities have also progressed towards possible large scale deployments. In this paper, we analyze the evolution of spectrum management policies using a causal model and indicate how the markets can lock in to either centralized or flexible approach. We also cite a use case of a flexible spectrum management approach using spectrum band fill option and indicate its suitability to the Indian context.

Serum Copper Level and Polycystic Ovarian Syndrome: A Meta-Analysis

2021 ◽  
pp. 1-8
Author(s):  
Qingtao Jiang ◽  
Feng Zhang ◽  
Lei Han ◽  
Baoli Zhu ◽  
Xin Liu
Keyword(s):  
Large Scale ◽  
Polycystic Ovarian Syndrome ◽  
Meta Analysis ◽  
Serum Copper ◽  
Copper Level ◽  
Serum Copper Level ◽  
Copper Status ◽  
Plasma Copper ◽  
Mean Differences ◽  
Ovarian Syndrome

<b><i>Introduction:</i></b> The association of serum copper with polycystic ovarian syndrome (PCOS) has been studied for years, but no definite conclusion is drawn. Therefore, we conducted a meta-analysis to investigate serum copper concentrations in PCOS subjects compared with healthy controls. <b><i>Methods:</i></b> Electronic search was performed in PubMed, Google Scholar, and Scopus up to June 30, 2020, without any restriction. Standardized mean differences (SMDs) with corresponding 95% CIs in serum copper levels were employed with random-effects model. <i>I</i><sup>2</sup> was applied to evaluate heterogeneity among studies. <b><i>Results:</i></b> Nine studies, measuring plasma copper levels in 1,168 PCOS patients and 1,106 controls, were included. Pooled effect size suggested serum copper level was significantly higher in women with PCOS (SMD = 0.51 μg/mL, 95% CI = [0.30, 0.72], <i>p</i> &#x3c; 0.0001). The overall heterogeneity was not connected with subgroups of the country, but derived from the opposite result of 1 study. <b><i>Conclusion:</i></b> Our research generally indicated circulating copper level in PCOS sufferers was significantly higher than normal controls. Large-scale studies are still needed to elucidate the clear relation between copper status and etiology of PCOS.

scholarly journals Mapping the adaptive landscape of a major agricultural pathogen reveals evolutionary constraints across heterogeneous environments

2021 ◽  
Author(s):  
Anik Dutta ◽  
Fanny E. Hartmann ◽  
Carolina Sardinha Francisco ◽  
Bruce A. McDonald ◽  
Daniel Croll
Keyword(s):  
Life History ◽  
Large Scale ◽  
Life History Traits ◽  
Genetic Correlations ◽  
Stress Factors ◽  
Life History Trait ◽  
Adaptive Landscape ◽  
Heterogeneous Environments ◽  
Growth Responses ◽  
Trade Offs

AbstractThe adaptive potential of pathogens in novel or heterogeneous environments underpins the risk of disease epidemics. Antagonistic pleiotropy or differential resource allocation among life-history traits can constrain pathogen adaptation. However, we lack understanding of how the genetic architecture of individual traits can generate trade-offs. Here, we report a large-scale study based on 145 global strains of the fungal wheat pathogen Zymoseptoria tritici from four continents. We measured 50 life-history traits, including virulence and reproduction on 12 different wheat hosts and growth responses to several abiotic stressors. To elucidate the genetic basis of adaptation, we used genome-wide association mapping coupled with genetic correlation analyses. We show that most traits are governed by polygenic architectures and are highly heritable suggesting that adaptation proceeds mainly through allele frequency shifts at many loci. We identified negative genetic correlations among traits related to host colonization and survival in stressful environments. Such genetic constraints indicate that pleiotropic effects could limit the pathogen’s ability to cause host damage. In contrast, adaptation to abiotic stress factors was likely facilitated by synergistic pleiotropy. Our study illustrates how comprehensive mapping of life-history trait architectures across diverse environments allows to predict evolutionary trajectories of pathogens confronted with environmental perturbations.

scholarly journals Adult body growth and reproductive investment vary markedly within and across Atlantic and Pacific herring: a meta-analysis and review of 26 stocks

2021 ◽  
Author(s):  
Thassya C. dos Santos Schmidt ◽  
Doug E. Hay ◽  
Svein Sundby ◽  
Jennifer A. Devine ◽  
Guðmundur J. Óskarsson ◽  
...  
Keyword(s):  
Egg Size ◽  
Meta Analysis ◽  
Reproductive Investment ◽  
Body Growth ◽  
Clupea Harengus ◽  
Pacific Herring ◽  
Atlantic Herring ◽  
Additional Information ◽  
Trade Offs ◽  
Investment In Reproduction

AbstractLife-history traits of Pacific (Clupea pallasii) and Atlantic (Clupea harengus) herring, comprising both local and oceanic stocks subdivided into summer-autumn and spring spawners, were extensively reviewed. The main parameters investigated were body growth, condition, and reproductive investment. Body size of Pacific herring increased with increasing latitude. This pattern was inconsistent for Atlantic herring. Pacific and local Norwegian herring showed comparable body conditions, whereas oceanic Atlantic herring generally appeared stouter. Among Atlantic herring, summer and autumn spawners produced many small eggs compared to spring spawners, which had fewer but larger eggs—findings agreeing with statements given several decades ago. The 26 herring stocks we analysed, when combined across distant waters, showed clear evidence of a trade-off between fecundity and egg size. The size-specific individual variation, often ignored, was substantial. Additional information on biometrics clarified that oceanic stocks were generally larger and had longer life spans than local herring stocks, probably related to their longer feeding migrations. Body condition was only weakly, positively related to assumingly in situ annual temperatures (0–30 m depth). Contrarily, body growth (cm × y−1), taken as an integrator of ambient environmental conditions, closely reflected the extent of investment in reproduction. Overall, Pacific and local Norwegian herring tended to cluster based on morphometric and reproductive features, whereas oceanic Atlantic herring clustered separately. Our work underlines that herring stocks are uniquely adapted to their habitats in terms of trade-offs between fecundity and egg size whereas reproductive investment mimics the productivity of the water in question.

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