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21.
伴随着社会经济的发展,社会公平逐渐成为热点话题。社会公平问题不但体现在社会现象上,还对生态系统起着重要的影响。通过构建资本交换自主体模型,模拟社会财富分配动态过程,可观测资本交换熵指数变化情况,从而解释熵增原理。除此以外,不同系统的最终状态能达到的最大熵指数不同,用熵增原理与本文构建的最大熵指数模型可以对系统的生态公平进行纵向或横向评价。构建的资本交换熵模型也可以证明最大熵原理,同时,财富集中的现象将会使生态环境的选择权完全交予富人群体,影响可持续发展。 相似文献
22.
Emilia L Lim Diane L Trinh David W Scott Andy Chu Martin Krzywinski Yongjun Zhao A Gordon Robertson Andrew J Mungall Jacqueline Schein Merrill Boyle Anja Mottok Daisuke Ennishi Nathalie A Johnson Christian Steidl Joseph M Connors Ryan D Morin Randy D Gascoyne Marco A Marra 《Genome biology》2015,16(1)
BackgroundDiffuse large B-cell lymphoma (DLBCL) is an aggressive disease, with 30% to 40% of patients failing to be cured with available primary therapy. microRNAs (miRNAs) are RNA molecules that attenuate expression of their mRNA targets. To characterize the DLBCL miRNome, we sequenced miRNAs from 92 DLBCL and 15 benign centroblast fresh frozen samples and from 140 DLBCL formalin-fixed, paraffin-embedded tissue samples for validation.ResultsWe identify known and candidate novel miRNAs, 25 of which are associated with survival independently of cell-of-origin and International Prognostic Index scores, which are established indicators of outcome. Of these 25 miRNAs, six miRNAs are significantly associated with survival in our validation cohort. Abundant expression of miR-28-5p, miR-214-5p, miR-339-3p, and miR-5586-5p is associated with superior outcome, while abundant expression of miR-324-5p and NOVELM00203M is associated with inferior outcome. Comparison of DLBCL miRNA-seq expression profiles with those from other cancer types identifies miRNAs that were more abundant in B-cell contexts. Unsupervised clustering of miRNAs identifies two clusters of patients that have distinct differences in their outcomes. Our integrative miRNA and mRNA expression analyses reveal that miRNAs increased in abundance in DLBCL appear to regulate the expression of genes involved in metabolism, cell cycle, and protein modification. Additionally, these miRNAs, including one candidate novel miRNA, miR-10393-3p, appear to target chromatin modification genes that are frequent targets of somatic mutation in non-Hodgkin lymphomas.ConclusionsOur comprehensive sequence analysis of the DLBCL miRNome identifies candidate novel miRNAs and miRNAs associated with survival, reinforces results from previous mutational analyses, and reveals regulatory networks of significance for lymphomagenesis.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0568-y) contains supplementary material, which is available to authorized users. 相似文献23.
Background
The Commission on Investing in Health published its report, GlobalHealth2035, in 2013, estimating an investment case for a grand convergence in health outcomes globally. In support of the drafting of the Sustainable Development Goals (SDGs), we estimate what the grand convergence investment case might achieve—and what investment would be required—by 2030.Methods and Findings
Our projection focuses on a sub-set of low-income (LIC) or lower-middle-income countries (LMIC). We start with a country-based (bottom-up) analysis of the costs and impact of scaling up reproductive, maternal, and child health tools, and select HIV and malaria interventions. We then incorporate global (top-down) analyses of the costs and impacts of scaling up existing tools for tuberculosis, additional HIV interventions, the costs to strengthen health systems, and the costs and benefits from scaling up new health interventions over the time horizon of this forecast. These data are then allocated to individual countries to provide an aggregate projection of potential cost and impact at the country level. Finally, incremental costs of R&D for low-income economies and the costs of addressing NTDs are added to provide a global total cost estimate of the investment scenario.Results
Compared with a constant coverage scenario, there would be more than 60 million deaths averted in LIC and 70 million deaths averted in LMIC between 2016 and 2030. For the years 2015, 2020, 2025, and 2030, the incremental costs of convergence in LIC would be (US billion) $24.3, $21.8, $24.7, and $27, respectively; in LMIC, the incremental costs would be (US billion) $34.75, $38.9, $48.7, and $56.3, respectively.Conclusion
Key health outcomes in low- and low-middle income countries can significantly converge with those of wealthier countries by 2030, and the notion of a “grand convergence” may serve as a unifying theme for health indicators in the SDGs. 相似文献24.
Michelle J. Boyle Prasanna Jagannathan Lila A. Farrington Ijeoma Eccles-James Samuel Wamala Tara I McIntyre Hilary M. Vance Katherine Bowen Felistas Nankya Ann Auma Mayimuna Nalubega Esther Sikyomu Kate Naluwu John Rek Agaba Katureebe Victor Bigira James Kapisi Jordan Tappero Mary K Muhindo Bryan Greenhouse Emmanuel Arinaitwe Grant Dorsey Moses R. Kamya Margaret E. Feeney 《PLoS pathogens》2015,11(7)
FoxP3+ regulatory CD4 T cells (Tregs) help to maintain the delicate balance between pathogen-specific immunity and immune-mediated pathology. Prior studies suggest that Tregs are induced by P. falciparum both in vivo and in vitro; however, the factors influencing Treg homeostasis during acute and chronic infections, and their role in malaria immunopathogenesis, remain unclear. We assessed the frequency and phenotype of Tregs in well-characterized cohorts of children residing in a region of high malaria endemicity in Uganda. We found that both the frequency and absolute numbers of FoxP3+ Tregs in peripheral blood declined markedly with increasing prior malaria incidence. Longitudinal measurements confirmed that this decline occurred only among highly malaria-exposed children. The decline of Tregs from peripheral blood was accompanied by reduced in vitro induction of Tregs by parasite antigen and decreased expression of TNFR2 on Tregs among children who had intense prior exposure to malaria. While Treg frequencies were not associated with protection from malaria, there was a trend toward reduced risk of symptomatic malaria once infected with P. falciparum among children with lower Treg frequencies. These data demonstrate that chronic malaria exposure results in altered Treg homeostasis, which may impact the development of antimalarial immunity in naturally exposed populations. 相似文献
25.
FCRL5 Delineates Functionally Impaired Memory B Cells Associated with Plasmodium falciparum Exposure
26.
Glucosylceramides are critical for cell‐type differentiation and organogenesis,but not for cell viability in Arabidopsis 下载免费PDF全文
Joseph Msanne Ming Chen Kyle D. Luttgeharm Amanda M. Bradley Elizabeth S. Mays Janet M. Paper Daniel L. Boyle Rebecca E. Cahoon Kathrin Schrick Edgar B. Cahoon 《The Plant journal : for cell and molecular biology》2015,84(1):188-201
Glucosylceramides (GlcCer), glucose‐conjugated sphingolipids, are major components of the endomembrane system and plasma membrane in most eukaryotic cells. Yet the quantitative significance and cellular functions of GlcCer are not well characterized in plants and other multi‐organ eukaryotes. To address this, we examined Arabidopsis lines that were lacking or deficient in GlcCer by insertional disruption or by RNA interference (RNAi) suppression of the single gene for GlcCer synthase (GCS, At2g19880), the enzyme that catalyzes GlcCer synthesis. Null mutants for GCS (designated ‘gcs‐1’) were viable as seedlings, albeit strongly reduced in size, and failed to develop beyond the seedling stage. Heterozygous plants harboring the insertion allele exhibited reduced transmission through the male gametophyte. Undifferentiated calli generated from gcs‐1 seedlings and lacking GlcCer proliferated in a manner similar to calli from wild‐type plants. However, gcs‐1 calli, in contrast to wild‐type calli, were unable to develop organs on differentiation media. Consistent with a role for GlcCer in organ‐specific cell differentiation, calli from gcs‐1 mutants formed roots and leaves on media supplemented with the glucosylated sphingosine glucopsychosine, which was readily converted to GlcCer independent of GCS. Underlying these phenotypes, gcs‐1 cells had altered Golgi morphology and fewer cisternae per Golgi apparatus relative to wild‐type cells, indicative of protein trafficking defects. Despite seedling lethality in the null mutant, GCS RNAi suppression lines with ≤2% of wild‐type GlcCer levels were viable and fertile. Collectively, these results indicate that GlcCer are essential for cell‐type differentiation and organogenesis, and plant cells produce amounts of GlcCer in excess of that required for normal development. 相似文献
27.
Improved white spruce (Picea glauca) genome assemblies and annotation of large gene families of conifer terpenoid and phenolic defense metabolism 下载免费PDF全文
René L. Warren Christopher I. Keeling Macaire Man Saint Yuen Anthony Raymond Greg A. Taylor Benjamin P. Vandervalk Hamid Mohamadi Daniel Paulino Readman Chiu Shaun D. Jackman Gordon Robertson Chen Yang Brian Boyle Margarete Hoffmann Detlef Weigel David R. Nelson Carol Ritland Nathalie Isabel Barry Jaquish Alvin Yanchuk Jean Bousquet Steven J. M. Jones John MacKay Inanc Birol Joerg Bohlmann 《The Plant journal : for cell and molecular biology》2015,83(2):189-212
28.
Using miniaturized radiotelemetry to discover the breeding grounds of the endangered New Zealand Storm Petrel Fregetta maoriana 下载免费PDF全文
Matt J. Rayner Chris P. Gaskin Neil B. Fitzgerald Karen A. Baird Martin M. Berg David Boyle Leigh Joyce Todd J. Landers Graeme G. Loh Sue Maturin Lyndon Perrimen R. Paul Scofield Joanna Simm Ian Southey Graeme A. Taylor Alan J. D. Tennyson Bruce C. Robertson Megan Young Richard Walle Stefanie M. H. Ismar 《Ibis》2015,157(4):754-766
Identification of breeding sites remains a critical step in species conservation, particularly in procellariiform seabirds whose threat status is of global concern. We designed and conducted an integrative radiotelemetry approach to uncover the breeding grounds of the critically endangered New Zealand Storm Petrel Fregetta maoriana (NZSP), a species considered extinct before its rediscovery in 2003. Solar‐powered automated radio receivers and hand‐held telemetry were used to detect the presence of birds on three island groups in the Hauraki Gulf near Auckland, New Zealand. At least 11 NZSP captured and radiotagged at sea were detected at night near Te Hauturu‐o‐Toi/Little Barrier Island with the detection of an incubating bird leading to the discovery of the first known breeding site for this species. In total, four NZSP breeding burrows were detected under mature forest canopy and three adult NZSP and two NZSP chicks were ringed. Telemetry data indicated NZSP showed strong moonlight avoidance behaviour over the breeding site, had incubation shifts of approximately 5 days and had a breeding season extending from February to June/July, a different season from other Procellariiformes in the region. Radiotelemetry, in combination with rigorously collected field data on species distribution, offers a valuable technique for locating breeding grounds of procellariiform seabirds and gaining insights into breeding biology while minimizing disturbance to sensitive species or damage to fragile habitat. Our study suggests an avenue for other breeding ground searches in one of the most threatened avian Orders, and highlights the general need for information on the location of breeding sites and understanding the breeding biology in data‐deficient birds. 相似文献
29.
Ants in their plants: Pseudomyrmex ants reduce primate,parrot and squirrel predation on Macrolobium acaciifolium (Fabaceae) seeds in Amazonian Brazil 下载免费PDF全文
Adrian A. Barnett Thais Almeida Richelly Andrade Sarah Boyle Marcelo Gonçalves de Lima Ann MacLarnon Caroline Ross Welma Sousa Silva Wilson R. Spironello Beatriz Ronchi‐Teles 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(2):260-273
Although plant‐inhabiting ants are known to act as effective deterrents to a variety of vertebrate and invertebrate herbivores, this has been reported only once before for primates, a group better known for their predation of ants. In the present study, we investigated the effects that colonies of Pseudomyrmex viduus ants living in individual Macrolobium acaciifolium (Fabaceae) trees have on the rates of visitation and fruit removal by four taxa of seed‐predating vertebrates: the primate Cacajao melanocephalus ouakary; macaws (Ara spp.); large parrots (Amazona spp.); and the Northern Amazonian red squirrel (Sciurus igniventris). We found that ant presence significantly reduced both rates of visitation and of fruit removal by C. m. ouakary. The same pattern of reduced fruit removal was also observed for other seed predators (parrots, macaws, and squirrels) but not for visitation rates (although this may be a result of the small sample size). This appears to be only the second‐known demonstration of the repellent effect of ants on primates and, indeed, the first for squirrels and psittacine birds. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 260–273. 相似文献
30.