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In the first part, the authors review a group of studies dealing with the identification of regional differences in Italian migratory patterns, especially using the concept of migration field. The second part is devoted to a study of the hierarchical clustering of Italian provinces using 1973 inter-provincial migratory flow data. (summary in ENG, FRE)  相似文献   
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Slater PB 《GeoJournal》1982,6(5):477-480
In contrast to results for several other nations, hierarchical regionalizations based upon 1960 Philippine lifetime migration do not indicate that islands act as migration regions — groups of provinces, relatively self-contained with respect to migration flows. Inter-island links seem to be more important than intra-island ties. Northern Luzon, the Bicol Peninsula and the Southern Philippines are among the regions that appear. Manila and its suburban province of Rizal are exceptional both for the breadth and strength of their interprovincial migration ties.  相似文献   
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Apatite fission track thermochronology (AFTT) and paleomagnetic (PM) results have been used to constrain the Late Paleozoic to Cenozoic landscape evolution of the Lachlan Fold Belt (LFB) around the Northparkes copper-gold deposit in east-central New South Wales. The present-day landscape of this region of the LFB is relatively flat with little expression of the underlying rock and has previously been interpreted to indicate long-term stability of the region since the end of LFB orogenesis in the Early Carboniferous. This was presumably borne out by PM analyses from thick weathered horizons within open pits at the mine, which suggested that significant periods of weathering, and hence relative landscape stability, prevailed during the Early to middle Carboniferous and at some time during the Cenozoic. Results from AFTT analyses, however, indicate that the region must have experienced significant episodes of cooling/denudation during the mid-Permian to mid-Triassic and during the early Cenozoic, as well as episodes of heating/burial during the Late Carboniferous to mid-Permian and during the late Mesozoic. When combined, the AFTT and PM results are in fact consistent and indicate that since the late Paleozoic the landscape of the LFB around the Northparkes deposit has evolved through multiple episodes of denudation and deposition as well as periods of relative stability during which the thick weathering horizons formed. Together these results establish a complementary chronological framework that constrains the Late Palaeozoic to Cenozoic landscape evolution of the Northparkes region and highlights the importance of using dual data sets in elucidating the long-term landscape evolution of similar "stable" terranes.  相似文献   
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This is a first foray into the historical start and early years of chemometrics from about 1972 onwards.We have gathered interviews with three originators(Kowalski,Wold and Massart)as well as with aselected group of six other well-known chemometricians who gradually became active in the 1970s(Christie,Clementi,Hopke,Martens,Brown and Deming).The interviews include amongst a host ofsubjective recollections a succinct record of the key historical literature as highlighted by the interviewees'own rankings of‘earliest’and‘best’.A discussion of the most general commonalities in these interviews together with other historicalmaterial is presented in the second part of the paper.  相似文献   
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目的:系统评价中西医结合治疗慢性子宫内膜炎的临床疗效,为临床治疗提供循证医学依据。方法:计算机检索万方数据(WANFANG DATA)、中国知网(CNKI)、维普中文科技期刊数据库(VIP)、中国生物医学文献数据库(CBM)、PubMed、Embase、Cochrane Library等中中西医结合治疗慢性子宫内膜炎的临床随机对照试验(RCT),检索时间从建库至2020年3月。采用“偏倚风险评估工具”进行质量评价,运用RevMan 5.3软件进行Meta分析,发表偏倚采用Stata 15.1软件进行分析。结果:纳入12个RCTs,共1273 例患者。Meta分析结果显示:中西医结合治疗在总有效率[RR=1.20,95%CI(1.15,1.25),Z=8.02(P<0.00001)]、月经经期恢复正常的发生率[RR=1.03,95%CI(1.15,1.47),Z=4.25(P<0.0001)]、经量恢复正常的发生率[RR=1.27,95%CI(1.13,1.43),Z=4.06(P<0.0001)]、改善子宫内膜厚度[MD=1.10,95%CI(0.92,1.29),Z=11.86(P<0.00001)]、减少显炎性图像[OR=0.20,95%CI(0.08,0.49),Z=3.53(P=0.0004)]、升高血清白细胞介素-2(IL-2)水平[SMD=3.69,95%CI(3.18,4.20),Z=14.24(P<0.00001)]、降低血清白细胞介素-1β(IL-1β)[SMD=-4.97,95%CI(-7.44,-2.49),Z=3.93(P<0.0001)]与肿瘤坏死因子-α(TNF-α)水平[SMD=-1.38,95%CI(-1.68,-1.08),Z=8.99(P<0.00001)]、不良反应发生率[OR=0.34,95%CI(0.15,0.75),Z=2.65(P=0.008)]方面,均优于单用西医治疗的对照组。结论:中西医结合治疗慢性子宫内膜炎的临床疗效优于单用西医治疗,值得临床推广应用。  相似文献   
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Concentrations of dissolved oxygen (DO) plotted vs. dissolved organic carbon (DOC) in groundwater samples taken from a coastal plain aquifer of South Carolina (SC) showed a statistically significant hyperbolic relationship. In contrast, DO-DOC plots of groundwater samples taken from the eastern San Joaquin Valley of California (CA) showed a random scatter. It was hypothesized that differences in the bioavailability of naturally occurring DOC might contribute to these observations. This hypothesis was examined by comparing nine different biochemical indicators of DOC bioavailability in groundwater sampled from these two systems. Concentrations of DOC, total hydrolysable neutral sugars (THNS), total hydrolysable amino acids (THAA), mole% glycine of THAA, initial bacterial cell counts, bacterial growth rates, and carbon dioxide production/consumption were greater in SC samples relative to CA samples. In contrast, the mole% glucose of THNS and the aromaticity (SUVA(254)) of DOC was greater in CA samples. Each of these indicator parameters were observed to change with depth in the SC system in a manner consistent with active biodegradation. These results are uniformly consistent with the hypothesis that the bioavailability of DOC is greater in SC relative to CA groundwater samples. This, in turn, suggests that the presence/absence of a hyperbolic DO-DOC relationship may be a qualitative indicator of relative DOC bioavailability in groundwater systems.  相似文献   
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Redox processes and water quality of selected principal aquifer systems   总被引:9,自引:0,他引:9  
Reduction/oxidation (redox) conditions in 15 principal aquifer (PA) systems of the United States, and their impact on several water quality issues, were assessed from a large data base collected by the National Water-Quality Assessment Program of the USGS. The logic of these assessments was based on the observed ecological succession of electron acceptors such as dissolved oxygen, nitrate, and sulfate and threshold concentrations of these substrates needed to support active microbial metabolism. Similarly, the utilization of solid-phase electron acceptors such as Mn(IV) and Fe(III) is indicated by the production of dissolved manganese and iron. An internally consistent set of threshold concentration criteria was developed and applied to a large data set of 1692 water samples from the PAs to assess ambient redox conditions. The indicated redox conditions then were related to the occurrence of selected natural (arsenic) and anthropogenic (nitrate and volatile organic compounds) contaminants in ground water. For the natural and anthropogenic contaminants assessed in this study, considering redox conditions as defined by this framework of redox indicator species and threshold concentrations explained many water quality trends observed at a regional scale. An important finding of this study was that samples indicating mixed redox processes provide information on redox heterogeneity that is useful for assessing common water quality issues. Given the interpretive power of the redox framework and given that it is relatively inexpensive and easy to measure the chemical parameters included in the framework, those parameters should be included in routine water quality monitoring programs whenever possible.  相似文献   
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东海盆地西湖凹陷致密砂岩气资源丰富,近年来古近系花港组成为勘探热点层位,但储层的致密化及与油气充注关系不明制约着花港组致密砂岩气的有效勘探和经济开发。在花港组储层特征的基础上,划分及厘定储层成岩作用类型与演化序列,恢复并揭示储层致密化过程及与油气充注的匹配关系。研究表明,西湖凹陷花港组储层砂岩主要经历压实、胶结和溶蚀3种成岩作用,压实作用是导致花港组储层孔隙损失和致密化的根本原因;并经历同生阶段、早成岩阶段(A、B期)和中成岩阶段(A、B期)共3阶段5期次的成岩演化过程;在中成岩阶段A2期时成岩环境开始由酸性向碱性发生转变,并伴随着晚期碳酸盐、硅质等胶结作用发育以及机械压实作用持续增强,储层逐渐趋于致密化;结合与油气主成藏期(7~0 Ma)的耦合关系将研究区花港组储层划分为3种类型:成藏未致密型储层、成藏同步致密型储层、成藏已致密型储层。研究梳理了西湖凹陷花港组储层特征、成岩演化序列、储层致密化及与油气充注的耦合关系,为下一步研究区致密砂岩气的勘探提供理论支持。   相似文献   
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