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排序方式: 共有154条查询结果,搜索用时 15 毫秒
81.
82.
Yancheva G Nowaczyk NR Mingram J Dulski P Schettler G Negendank JF Liu J Sigman DM Peterson LC Haug GH 《Nature》2007,445(7123):74-77
The Asian-Australian monsoon is an important component of the Earth's climate system that influences the societal and economic activity of roughly half the world's population. The past strength of the rain-bearing East Asian summer monsoon can be reconstructed with archives such as cave deposits, but the winter monsoon has no such signature in the hydrological cycle and has thus proved difficult to reconstruct. Here we present high-resolution records of the magnetic properties and the titanium content of the sediments of Lake Huguang Maar in coastal southeast China over the past 16,000 years, which we use as proxies for the strength of the winter monsoon winds. We find evidence for stronger winter monsoon winds before the B?lling-Aller?d warming, during the Younger Dryas episode and during the middle and late Holocene, when cave stalagmites suggest weaker summer monsoons. We conclude that this anticorrelation is best explained by migrations in the intertropical convergence zone. Similar migrations of the intertropical convergence zone have been observed in Central America for the period ad 700 to 900 (refs 4-6), suggesting global climatic changes at that time. From the coincidence in timing, we suggest that these migrations in the tropical rain belt could have contributed to the declines of both the Tang dynasty in China and the Classic Maya in Central America. 相似文献
83.
Joe T. Smith Lester D. Flake Kenneth F. Higgins Gerald D. Kobriger Collin G. Homer 《西北部美国博物学家》2011,65(3)
Greater Sage-Grouse ( Centrocercus urophasianus ) have been declining in many states and provinces of North America, and North and South Dakota hold no exception to these declines. We studied effects of cultivated land on Greater Sage-Grouse lek abandonment in North and South Dakota. Landscape-level data were assessed using satellite imagery within a geographic information system. Comparisons were made of 1972-1976 and 1999-2000 percent cultivated and noncultivated land. These comparisons were made between land uses surrounding active leks versus inactive leks, active leks versus random locations, and abandoned regions versus active regions. The 1999-2000 imagery illustrated that percent cultivated land was greater near abandoned leks (4-km buffers) than near active leks in North Dakota or random sites, but this did not hold true in South Dakota. Comparison of an extensive region of abandoned leks with a region of active leks in North Dakota illustrated a similar increase as well as dispersion of cultivation within the abandoned region. However, 1972-1976 imagery revealed that this relationship between percentage of cultivated land and lek activity in North Dakota has been static over the last 30 years. Thus, if the decline of Greater Sage-Grouse is the result of cultivated land infringements, it occurred prior to 1972 in North Dakota. 相似文献
84.
Gerald Midgley 《Systemic Practice and Action Research》2007,20(3):195-210
This paper presents a Buddhist systems methodology (BSM) designed for problem prevention and problem solving in Taiwanese
Buddhist organisations. Three sets of twelve questions based on Buddhist concepts are offered to (i) support explorations
of boundaries and values in problematic situations; (ii) guide the choice of methods for intervention; and (iii) support the
evaluation of recommendations for change. The paper argues that the BSM has advantages in Taiwanese contexts compared with
Western systems approaches. The latter can appear threatening to organizational harmony and can therefore be regarded negatively.
In contrast, the BSM uses Buddhist concepts that are closely associated with the practice of harmonious living. Thus, it reframes
systems thinking as the exercise of Buddhist discipline applied to organizational life, and is likely to be viewed as a co-operative
and culturally valued endeavour.
相似文献
Chao Ying ShenEmail: |
85.
86.
Thirty new loci for age at menarche identified by a meta-analysis of genome-wide association studies
Elks CE Perry JR Sulem P Chasman DI Franceschini N He C Lunetta KL Visser JA Byrne EM Cousminer DL Gudbjartsson DF Esko T Feenstra B Hottenga JJ Koller DL Kutalik Z Lin P Mangino M Marongiu M McArdle PF Smith AV Stolk L van Wingerden SH Zhao JH Albrecht E Corre T Ingelsson E Hayward C Magnusson PK Smith EN Ulivi S Warrington NM Zgaga L Alavere H Amin N Aspelund T Bandinelli S Barroso I Berenson GS Bergmann S Blackburn H Boerwinkle E Buring JE Busonero F Campbell H Chanock SJ Chen W Cornelis MC 《Nature genetics》2010,42(12):1077-1085
To identify loci for age at menarche, we performed a meta-analysis of 32 genome-wide association studies in 87,802 women of European descent, with replication in up to 14,731 women. In addition to the known loci at LIN28B (P = 5.4 × 10???) and 9q31.2 (P = 2.2 × 10?33), we identified 30 new menarche loci (all P < 5 × 10??) and found suggestive evidence for a further 10 loci (P < 1.9 × 10??). The new loci included four previously associated with body mass index (in or near FTO, SEC16B, TRA2B and TMEM18), three in or near other genes implicated in energy homeostasis (BSX, CRTC1 and MCHR2) and three in or near genes implicated in hormonal regulation (INHBA, PCSK2 and RXRG). Ingenuity and gene-set enrichment pathway analyses identified coenzyme A and fatty acid biosynthesis as biological processes related to menarche timing. 相似文献
87.
Stuart PE Nair RP Ellinghaus E Ding J Tejasvi T Gudjonsson JE Li Y Weidinger S Eberlein B Gieger C Wichmann HE Kunz M Ike R Krueger GG Bowcock AM Mrowietz U Lim HW Voorhees JJ Abecasis GR Weichenthal M Franke A Rahman P Gladman DD Elder JT 《Nature genetics》2010,42(11):1000-1004
We carried out a meta-analysis of two recent psoriasis genome-wide association studies with a combined discovery sample of 1,831 affected individuals (cases) and 2,546 controls. One hundred and two loci selected based on P value rankings were followed up in a three-stage replication study including 4,064 cases and 4,685 controls from Michigan, Toronto, Newfoundland and Germany. In the combined meta-analysis, we identified three new susceptibility loci, including one at NOS2 (rs4795067, combined P = 4 × 10?11), one at FBXL19 (rs10782001, combined P = 9 × 10?1?) and one near PSMA6-NFKBIA (rs12586317, combined P = 2 × 10??). All three loci were also associated with psoriatic arthritis (rs4795067, combined P = 1 × 10??; rs10782001, combined P = 4 × 10??; and rs12586317, combined P = 6 × 1??) and purely cutaneous psoriasis (rs4795067, combined P = 1 × 10??; rs10782001, combined P = 2 × 10??; and rs12586317, combined P = 1 × 10??). We also replicated a recently identified association signal near RNF114 (rs495337, combined P = 2 × 10??). 相似文献
88.
Gerald Holton 《自然科学史研究》2005,24(B07):75-82
Historians of modem science have good reasons to be grateful to Paul Arthur Schilpp, professor of philosophy and Methodist clergyman but better known as the editor of a series of volumes on“ Living Philosophers”, including several on scientist-philosophers. His motto was: “The asking of questions about a philosopher's meaning while he is alive.” 相似文献
89.
Gerald Holton 《自然科学史研究》2005,24(Z1):75-82
Ⅰ
Historians of modern science have good reasons to be grateful to Paul Arthur Schilpp, professor of philosophy and Methodist clergyman but better known as the editor of a series of volumes on" Living Philosophers", including several on scientist-philosophers. His motto was:"The asking of questions about a philosopher's meaning while he is alive." And to his everlasting credit, he persuaded Albert Einstein to do what he had resisted all his years: to sit down to write, in 1946 at age sixty-seven, an extensive autobiography-forty-five pages long in print. 相似文献
90.