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排序方式: 共有1357条查询结果,搜索用时 15 毫秒
31.
Suzanne M. Marselis Katharine Abernethy Alfonso Alonso John Armston Timothy R. Baker Jean‐Francois Bastin Jan Bogaert Doreen S. Boyd Pascal Boeckx David F. R. P. Burslem Robin Chazdon David B. Clark David Coomes Laura Duncanson Steven Hancock Ross Hill Chris Hopkinson Elizabeth Kearsley James R. Kellner David Kenfack Nicolas Labrire Simon L. Lewis David Minor Herv Memiaghe Abel Monteagudo Reuben Nilus Michael O'Brien Oliver L. Phillips John Poulsen Hao Tang Hans Verbeeck Ralph Dubayah 《Global Ecology and Biogeography》2020,29(10):1799-1816
32.
How to measure,report and verify soil carbon change to realize the potential of soil carbon sequestration for atmospheric greenhouse gas removal 总被引:1,自引:0,他引:1
Pete Smith Jean‐Francois Soussana Denis Angers Louis Schipper Claire Chenu Daniel P. Rasse Niels H. Batjes Fenny van Egmond Stephen McNeill Matthias Kuhnert Cristina Arias‐Navarro Jorgen E. Olesen Ngonidzashe Chirinda Dario Fornara Eva Wollenberg Jorge lvaro‐Fuentes Alberto Sanz‐Cobena Katja Klumpp 《Global Change Biology》2020,26(1):219-241
There is growing international interest in better managing soils to increase soil organic carbon (SOC) content to contribute to climate change mitigation, to enhance resilience to climate change and to underpin food security, through initiatives such as international ‘4p1000’ initiative and the FAO's Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading. Without such platforms, investments could be considered risky. In this paper, we review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. We describe how repeat soil surveys are used to estimate changes in SOC over time, and how long‐term experiments and space‐for‐time substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. We briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for SOC change already in use in various countries/regions. In the final section, we bring together the various components described in this review, to describe a new vision for a global framework for MRV of SOC change, to support national and international initiatives seeking to effect change in the way we manage our soils. 相似文献
33.
Pamela McElwee Katherine Calvin Donovan Campbell Francesco Cherubini Giacomo Grassi Vladimir Korotkov Anh Le Hoang Shuaib Lwasa Johnson Nkem Ephraim Nkonya Nobuko Saigusa Jean‐Francois Soussana Miguel Angel Taboada Frances Manning Dorothy Nampanzira Pete Smith 《Global Change Biology》2020,26(9):4691-4721
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation. 相似文献
34.
Vincent A. Viblanc Quentin Schull Antoine Stier Laureline Durand Emilie Lefol Jean‐Patrice Robin Sandrine Zahn Pierre Bize Franois Criscuolo 《Molecular ecology》2020,29(16):3154-3166
Because telomere length and dynamics relate to individual growth, reproductive investment and survival, telomeres have emerged as possible markers of individual quality. Here, we tested the hypothesis that, in species with parental care, parental telomere length can be a marker of parental quality that predicts offspring phenotype and survival. In king penguins (Aptenodytes patagonicus), we experimentally swapped the single egg of 66 breeding pairs just after egg laying to disentangle the contribution of prelaying parental quality (e.g., genetics, investment in the egg) and/or postlaying parental quality (e.g., incubation, postnatal feeding rate) on offspring growth, telomere length and survival. Parental quality was estimated through the joint effects of biological and foster parent telomere length on offspring traits, both soon after hatching (day 10) and at the end of the prewinter growth period (day 105). We expected that offspring traits would be mostly related to the telomere lengths (i.e., quality) of biological parents at day 10 and to the telomere lengths of foster parents at day 105. Results show that chick survival up to 10 days was negatively related to biological fathers’ telomere length, whereas survival up to 105 days was positively related to foster fathers’ telomere lengths. Chick growth was not related to either biological or foster parents’ telomere length. Chick telomere length was positively related to foster mothers’ telomere length at both 10 and 105 days. Overall, our study shows that, in a species with biparental care, parents’ telomere length is foremost a proxy of postlaying parental care quality, supporting the “telomere – parental quality hypothesis.” 相似文献
35.
Esterhuizen Karien Lindeque J. Zander Mason Shayne van der Westhuizen Francois H. Rodenburg Richard J. de Laat Paul Smeitink Jan A. M. Janssen Mirian C. H. Louw Roan 《Metabolomics : Official journal of the Metabolomic Society》2021,17(1):1-11
Metabolomics - Studies investigating crop resistance to abiotic and biotic stress have largely focused on plant responses to singular forms of stress and individual biochemical pathways that only... 相似文献
36.
Francois Korbmacher Benjamin Drepper Theo Sanderson Peer Martin Thomas Stach Alexander G. Maier Kai Matuschewski Joachim M. Matz 《Cellular microbiology》2021,23(1)
Malaria parasites are fast replicating unicellular organisms and require substantial amounts of folate for DNA synthesis. Despite the central role of this critical co‐factor for parasite survival, only little is known about intraparasitic folate trafficking in Plasmodium. Here, we report on the expression, subcellular localisation and function of the parasite's folate transporter 2 (FT2) during life cycle progression in the murine malaria parasite Plasmodium berghei. Using live fluorescence microscopy of genetically engineered parasites, we demonstrate that FT2 localises to the apicoplast. In invasive P. berghei stages, a fraction of FT2 is also observed at the apical end. Upon genetic disruption of FT2, blood and liver infection, gametocyte production and mosquito colonisation remain unaltered. But in the Anopheles vector, FT2‐deficient parasites develop inflated oocysts with unusual pulp formation consisting of numerous single‐membrane vesicles, which ultimately fuse to form large cavities. Ultrastructural analysis suggests that this defect reflects aberrant sporoblast formation caused by abnormal vesicular traffic. Complete sporogony in FT2‐deficient oocysts is very rare, and mutant sporozoites fail to establish hepatocyte infection, resulting in a complete block of parasite transmission. Our findings reveal a previously unrecognised organellar folate transporter that exerts critical roles for pathogen maturation in the arthropod vector. 相似文献
37.
There is often a lack of basic ecological data needed to implement effective conservation management programmes for endangered arthropods. This is particularly true for the highly localized and rare Colophon, a genus of beetles of which all members are narrow range endemics of conservation concern. The genus is confined to the highest mountain peaks in the Cape Floristic Region of South Africa and each of the 17 known species is endemic to a particular mountain or range. We investigated the influence of selected abiotic variables on adult Colophon westwoodi activity in Table Mountain National Park, South Africa, which will aid the development of an effective monitoring programme. Weekly surveys conducted on Table Mountain showed that adult numbers peaked during early summer. Adults were active at dusk on clear days, although earlier when misty. Unexpectedly, relative humidity and air temperature had no significant effect on Colophon abundance, while illuminance was the most important predictor. Contrary to general consensus, C. westwoodi activity is not strictly crepuscular but also appears nocturnal. Thus, Colophon monitoring programmes need to be conducted in early summer after sunset and monitoring can continue later than previously assumed. Little is still known about C. westwoodi population size, area of occupancy, general behaviour and the impact tourists have on it, or indeed why the genus is restricted to mountain tops. Therefore this research is important for the design of monitoring protocols for this flagship species, while at the same time directing future research. 相似文献
38.
Anneleen Daemen Obi L Griffith Laura M Heiser Nicholas J Wang Oana M Enache Zachary Sanborn Francois Pepin Steffen Durinck James E Korkola Malachi Griffith Joe S Hur Nam Huh Jongsuk Chung Leslie Cope Mary Jo Fackler Christopher Umbricht Saraswati Sukumar Pankaj Seth Vikas P Sukhatme Lakshmi R Jakkula Yiling Lu Gordon B Mills Raymond J Cho Eric A Collisson Laura J van’t Veer Paul T Spellman Joe W Gray 《Genome biology》2013,14(10):R110
39.
Sophie Reichert Fran?ois Criscuolo Elodie Verinaud Sandrine Zahn Sylvie Massemin 《PloS one》2013,8(12)
Telomeres are repetitive non coding DNA sequences located at the end of eukaryotic chromosomes, which maintain the integrity of the genome by hiding the chromosome ends from being recognised as double stranded breaks. Telomeres are emerging as biomarkers for ageing and survival, and are susceptible to reflect different individual life history trajectories. In particular, the telomere length with which one starts in life has been shown to be linked with individual life-long survival, suggesting that telomere dynamics can be a proxy for individual fitness and thereby be implicated in evolutionary trade-offs. As a consequence, an increasing number of studies were conducted on telomeres in the fields of ecology and evolutionary biology, in which telomere length was almost exclusively measured from blood samples. However, not only do the number of repeats of the telomeric sequences vary among species, but also within species with great inter-individual telomere lengths variability with age, tissues, and chromosomes. This raises the issue of the exact biological meaning of telomere measurement in blood cells and stimulated the study of the correlation of telomere lengths among tissues over age. By measuring telomere length in adult zebra finches (Taeniopygia guttata) in different somatic tissues displaying variable cell turnovers (bone marrow, brain, spleen, pectoral muscle, heart, liver and in red blood cells), we checked that the measure of telomere length in red blood cells is related to telomere lengths in the other tissues. Here we show significant relationships between the telomere lengths of red blood cells and several somatic tissues at adulthood. As red blood cells are easily accessible and suitable for the longitudinal monitoring of the individual rate of telomere loss, our study confirms that telomere length measured in red blood cells could serve as a surrogate for telomere length in the whole avian organism. 相似文献
40.
Genetic inactivation of PTEN through either gene deletion or mutation is common in metastatic prostate cancer, leading to activation of the phosphoinositide 3-kinase (PI3K-AKT) pathway, which is associated with poor clinical outcomes. The PI3K-AKT pathway plays a central role in various cellular processes supporting cell growth and survival of tumor cells. To date, therapeutic approaches to develop inhibitors targeting the PI3K-AKT pathway have failed in both pre-clinical and clinical trials. We showed that a novel AKT inhibitor, AZD5363, inhibits the AKT downstream pathway by reducing p-MTOR and p-RPS6KB/p70S6K. We specifically reported that AZD5363 monotherapy induces G2 growth arrest and autophagy, but fails to induce significant apoptosis in PC-3 and DU145 prostate cancer cell lines. Blocking autophagy using pharmacological inhibitors (3-methyladenine, chloroquine and bafilomycin A1) or genetic inhibitors (siRNA targeting ATG3 and ATG7) enhances cell death induced by AZD5363 in these prostate cancer cells. Importantly, the combination of AZD5363 with chloroquine significantly reduces tumor volume compared with the control group, and compared with either drug alone in prostate tumor xenograft models. Taken together, these data demonstrate that AKT inhibitor AZD5363, synergizes with the lysosomotropic inhibitor of autophagy, chloroquine, to induce apoptosis and delay tumor progression in prostate cancer models that are resistant to monotherapy, with AZD5363 providing a new therapeutic approach potentially translatable to patients. 相似文献