827 research outputs found
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Correlates of long-term land-cover change and protected area performance at priority conservation sites in Africa
The loss of natural habitats is a major threat to biodiversity, and protected area designation is one of the standard responses to this threat. However, greater understanding of the drivers of habitat loss and of the circumstances under which protected areas succeed or fail is still needed. We use visual assessment of satellite images to quantify land-cover change over periods of up to 30 years in and around a matched sample of protected and unprotected Important Bird and Biodiversity Areas (IBAs) in Africa. We modelled the annual survival of forests and other natural land covers as a function of a range of environmental and anthropic predictors of plausible drivers. The best-supported model indicated that survival rates of natural land cover were highest in steeper areas, at higher altitudes, in areas with lower human population densities and in areas where the cover of natural habitats was already higher at the start of the period. Survival rates of natural land cover in protected areas were, on average, around twice those in unprotected areas, but the differences between them varied along different environmental gradients. The overall survival rates of both protected and unprotected forests were significantly lower than those of other natural land-cover types, but the net benefit of protection, in terms of the absolute difference in rates of loss between protected and unprotected sites, was higher in forests. Interaction terms indicated that as slope and altitude increased, the natural protection offered by topography increasingly nullified the additional benefits of legislative protection. Furthermore, protected area designation offered reduced additional benefits to the survival of natural land cover in areas where rates of conversion were higher at the start of the observation period. Variation in the impacts of protected area status along different environmental gradients indicates that targets to improve the world's protected area network, such as Aichi Target 11 of the Convention on Biological Diversity, need to look beyond simple area-based metrics. Our methods and results contribute to the development of a protocol for prioritizing places where protection is likely to have the greatest effect.This work was partly supported by the Cambridge Conservation Initiative Collaborative Fund, through the generosity of Arcadia (grant CCI 09/09 009) and by King's College Cambridge (B. Phalan, Zukerman Junior Research Fellowship)
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Modelling the potential non-breeding distribution of Spoon-billed Sandpiper Calidris pygmaea
SummaryThe Spoon-billed Sandpiper Calidris pygmaea is a âCritically Endangeredâ migratory shorebird. The species faces an array of threats in its non-breeding range, making conservation intervention essential. However, conservation efforts are reliant on identifying the speciesâ key stopover and wintering sites. Using Maximum Entropy models, we predicted Spoon-billed Sandpiper distribution across the non-breeding range, using data from recent field surveys and satellite tracking. Model outputs suggest only a limited number of stopover sites are suitable for migrating birds, with sites in the Yellow Sea and on the Jiangsu coast in China highlighted as particularly important. All the previously known core wintering sites were identified by the model including the Ganges-Brahmaputra Delta, Nan Thar Island and the Gulf of Mottama. In addition, the model highlighted sites subsequently found to be occupied, and pinpointed potential new sites meriting investigation, notably on Borneo and Sulawesi, and in parts of India and the Philippines. A comparison between the areas identified as most likely to be occupied and protected areas showed that very few locations are covered by conservation designations. Known sites must be managed for conservation as a priority, and potential new sites should be surveyed as soon as is feasible to assess occupancy status. Site protection should take place in concert with conservation interventions including habitat management, discouraging hunting, and fostering alternative livelihoods.Field surveys in Russian non-breeding grounds were supported by RSPB, MHS and NABU. Field surveys in Gulf of Mottama partly supported by BBC Wildlife Fund. Satellite tagging data collection partly supported by The Biodiversity Investigation, Observation and Assessment Program (2019 - 2023) of the Ministry of Ecology and Environment of China, RSPB and a private donor. Bangladesh Spoon-billed Sandpiper Conservation Projectâs fieldwork in Meghna Estuary (2015 - 2016) supported by RSPB. Data collection by EL partly supported by Basic research program (budgetary funds), projects number ĐĐĐĐ-Đ19-119022190168-8 and ĐĐĐĐ-Đ19-119021990093-8). PT supported by Moscow State University Grant for Leading Scientific Schools "Depository of the Living Systems" in the MSU Development Program framework. TBL was funded by the Natural Environment Research Council UK, and the IAPETUS Doctoral Training Partnership
Vitamin D supplementation and breast cancer prevention : a systematic review and meta-analysis of randomized clinical trials
In recent years, the scientific evidence linking vitamin D status or supplementation to breast cancer has grown notably. To investigate the role of vitamin D supplementation on breast cancer incidence, we conducted a systematic review and meta-analysis of randomized controlled trials comparing vitamin D with placebo or no treatment. We used OVID to search MEDLINE (R), EMBASE and CENTRAL until April 2012. We screened the reference lists of included studies and used the âRelated Articleâ feature in PubMed to identify additional articles. No language restrictions were applied. Two reviewers independently extracted data on methodological quality, participants, intervention, comparison and outcomes. Risk Ratios and 95% Confident Intervals for breast cancer were pooled using a random-effects model. Heterogeneity was assessed using the I2 test. In sensitivity analysis, we assessed the impact of vitamin D dosage and mode of administration on treatment effects. Only two randomized controlled trials fulfilled the pre-set inclusion criteria. The pooled analysis included 5372 postmenopausal women. Overall, Risk Ratios and 95% Confident Intervals were 1.11 and 0.74â1.68. We found no evidence of heterogeneity. Neither vitamin D dosage nor mode of administration significantly affected breast cancer risk. However, treatment efficacy was somewhat greater when vitamin D was administered at the highest dosage and in combination with calcium (Risk Ratio 0.58, 95% Confident Interval 0.23â1.47 and Risk Ratio 0.93, 95% Confident Interval 0.54â1.60, respectively). In conclusions, vitamin D use seems not to be associated with a reduced risk of breast cancer development in postmenopausal women. However, the available evidence is still limited and inadequate to draw firm conclusions. Study protocol code: FARM8L2B5L
Free satellite data key to conservation
Biodiversity is in crisis, with extinction rates orders of magnitude higher than background levels ([ 1 ][1]). Underfunded conservationists need to target their limited resources effectively. Over the past decade, satellite remote sensing has revolutionized our ability to monitor biodiversity globally, and is now used routinely, especially by nongovernmental organizations, to detect changes, set priorities, and target conservation action. The U.S. Geological Survey (USGS) unlocked high-resolution Landsat data in 2008 ([ 2 ][2]), making data available online ([ 3 ][3]), and the Copernicus program from the European Commission subsequently made their data available as well ([ 4 ][4]). These resources have been instrumental to biodiversity research. Assessments of environmental changes such as deforestation are now readily available. The current spatial and spectral resolution of Landsat data make them appropriate to many conservation applications, and although they are not always ideal, pragmatic researchers with limited resources use them regularly. Conservationists have already called for these data to remain free ([ 5 ][5]). Consequently, the news that USGS may charge for data ([ 6 ][6]) is deeply troubling. USGS has recently convened an advisory committee to determine whether users would be prepared to pay for increased spectral and spatial resolution images ([ 7 ][7]). Requiring users to pay would put these images beyond the reach of conservationists. It would halt time-series analyses that have been useful in monitoring the effects of climate change, land-cover change, and ocean surfaces, likely hindering the achievement of the Sustainable Development Goals ([ 8 ][8]). We urge the USGS to reconsider their position and continue to provide data from the Landsat program freely to all users. 1. [â”][9]1. J. DeVos et al ., Cons. Biol. 29, 452 (2015). [OpenUrl][10] 2. [â”][11]1. C. Woodcock et al . Science 320, 1011 (2008). [OpenUrl][12][CrossRef][13][PubMed][14] 3. [â”][15]USGS, Earth Explorer ([https://earthexplorer.usgs.gov/][16]). 4. [â”][17]European Commission, Copernicus (). 5. [â”][18]1. W. Turner et al ., Biol. Conserv. 182, 173 (2015). [OpenUrl][19] 6. [â”][20]1. G. Popkin , Nature 556, 417 (2018). [OpenUrl][21] 7. [â”][22]USGS, Landsat Advisory Group undertakes a Landsat Cost Recovery Study (2018); [www.usgs.gov/center-news/landsat-advisory-group-undertakes-a-landsat-cost-recovery-study][23]. 8. [â”][24]Sustainable Development Goals ([https://sustainabledevelopment.un.org/?menu=1300][25]). [1]: #ref-1 [2]: #ref-2 [3]: #ref-3 [4]: #ref-4 [5]: #ref-5 [6]: #ref-6 [7]: #ref-7 [8]: #ref-8 [9]: #xref-ref-1-1 "View reference 1 in text" [10]: {openurl}?query=rft.jtitle%253DCons.%2BBiol.%26rft.volume%253D29%26rft.spage%253D452%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [11]: #xref-ref-2-1 "View reference 2 in text" [12]: {openurl}?query=rft.jtitle%253DScience%26rft.volume%253D320%26rft.spage%253D1011%26rft_id%253Dinfo%253Adoi%252F10.1126%252Fscience.320.5879.1011a%26rft_id%253Dinfo%253Apmid%252F18497274%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [13]: /lookup/external-ref?access_num=10.1126/science.320.5879.1011a&link_type=DOI [14]: /lookup/external-ref?access_num=18497274&link_type=MED&atom=%2Fsci%2F361%2F6398%2F139.2.atom [15]: #xref-ref-3-1 "View reference 3 in text" [16]: http://earthexplorer.usgs.gov/ [17]: #xref-ref-4-1 "View reference 4 in text" [18]: #xref-ref-5-1 "View reference 5 in text" [19]: {openurl}?query=rft.jtitle%253DBiol.%2BConserv.%26rft.volume%253D182%26rft.spage%253D173%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [20]: #xref-ref-6-1 "View reference 6 in text" [21]: {openurl}?query=rft.jtitle%253DNature%26rft.volume%253D556%26rft.spage%253D417%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [22]: #xref-ref-7-1 "View reference 7 in text" [23]: http://www.usgs.gov/center-news/landsat-advisory-group-undertakes-a-landsat-cost-recovery-study [24]: #xref-ref-8-1 "View reference 8 in text" [25]: http://sustainabledevelopment.un.org/?menu=130
Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.
The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition
Local biodiversity is higher inside than outside terrestrial protected areas worldwide
Protected areas are widely considered essential for biodiversity conservation. However, few global studies have demonstrated that protection benefits a broad range of species. Using a new global biodiversity database with unprecedented geographic and taxonomic coverage, we compare four biodiversity measures at sites sampled in multiple land uses inside and outside protected areas. Globally, species richness is 10.7% higher and abundance 14.5% higher in samples taken inside protected areas compared to samples taken outside, but neither rarefaction-based richness nor endemicity differ significantly. Importantly, we show that the positive effects of protection are mostly attributable to differences in land use between protected and unprotected sites. Nonetheless, even within some human-dominated land uses, species richness and abundance are higher in protected sites. Our results reinforce the global importance of protected areas but suggest that protection does not consistently benefit species with small ranges or increase the variety of ecological niches
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at â s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fbâ1 of â s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
Role of Ox-PAPCs in the Differentiation of Mesenchymal Stem Cells (MSCs) and Runx2 and PPARÎł2 Expression in MSCs-Like of Osteoporotic Patients
BACKGROUND: Mesenchymal stem cells (MSCs) can differentiate into osteoblasts and adipocytes and conditions causing bone loss may induce a switch from the osteoblast to adipocyte lineage. In addition, the expression of Runx2 and the PPARÎł2 transcription factor genes is essential for cellular commitment to an osteogenic and adipogenic differentiation, respectively. Modified lipoproteins derived from the oxidation of arachidonate-containing phospholipids (ox-PAPCs: POVPC, PGPC and PEIPC) are considered important factors in atherogenesis. METHODOLOGY: We investigated the effect of ox-PAPCs on osteogenesis and adipogenesis in human mesenchymal stem cells (hMSCs). In particular, we analyzed the transcription factor Runx2 and the PPARÎł2 gene expression during osteogenic and adipogenic differentiation in absence and in presence of ox-PAPCs. We also analyzed gene expression level in a panel of osteoblastic and adipogenic differentiation markers. In addition, as circulating blood cells can be used as a "sentinel" that responds to changes in the macro- or micro-environment, we analyzed the Runx2 and the PPARÎł2 gene expression in MSCs-like and ox-PAPC levels in serum of osteoporotic patients (OPs). Finally, we examined the effects of sera obtained from OPs in hMSCs comparing the results with age-matched normal donors (NDs). PRINCIPAL FINDINGS: Quantitative RT-PCR demonstrated that ox-PAPCs enhanced PPARÎł2 and adipogenic gene expression and reduced Runx2 and osteoblast differentiation marker gene expression in differentiating hMSCs. In OPs, ox-PAPC levels and PPARÎł2 expression were higher than in NDs, whereas Runx2 was lower than in ND circulant MSCs-like. CONCLUSIONS: Ox-PAPCs affect the osteogenic differentiation by promoting adipogenic differentiation and this effect may appear involved in bone loss in OPs
The combination of Ki67, histological grade and estrogen receptor status identifies a low-risk group among 1,854 chemo-naĂŻve women with N0/N1 primary breast cancer
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