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中国省域人口空间结构特征及其对经济绩效的影响——基于实体城市的空间识别 被引量:18
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作者 孙斌栋 张之帆 李琬 《地理科学》 CSSCI CSCD 北大核心 2021年第11期1884-1896,共13页
基于LandScan全球人口和ESA全球土地利用数据,构建2000—2015年中国省域人口空间结构数据库,刻画省域人口空间结构的时空格局,进而运用面板固定效应法、两阶段最小二乘法和差分GMM法探索空间结构对省域经济绩效的影响及这种影响对不同... 基于LandScan全球人口和ESA全球土地利用数据,构建2000—2015年中国省域人口空间结构数据库,刻画省域人口空间结构的时空格局,进而运用面板固定效应法、两阶段最小二乘法和差分GMM法探索空间结构对省域经济绩效的影响及这种影响对不同规模省域的差异,最后从省会城市集聚(不)经济的角度分析其内在机制。结果发现:(1)2000—2015年,中国所有省会城市的人口规模都得到了显著增加,省域人口空间结构存在单中心化的演变趋势,且中西部地区省域人口空间结构相对偏单中心化;(2)对所有省份尤其是人口规模相对较小的省份而言,人口空间结构单中心化倾向于提高省域经济效率,而对人口规模相对大的省份,人口空间结构单中心化很可能不利于省域经济效率的提高;(3)省会城市自身已经初显集聚不经济的迹象。 展开更多
关键词 “强省会”战略 人口空间布局 中心化人口空间结构 经济绩效 省域
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动态死亡率模型的研究进展 被引量:7
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作者 王晓军 路倩 《应用概率统计》 CSCD 北大核心 2020年第4期415-440,共26页
死亡率的预测是人口预测的基础.近年来,死亡率建模方法不断取得新的进展,从最早的静态死亡率模型开始,死亡率模型不断发展为包括时间项的动态预测模型,如Lee-Carter族模型、CBD族模型等.本文对死亡率预测模型的相关文献进行了回顾和梳理... 死亡率的预测是人口预测的基础.近年来,死亡率建模方法不断取得新的进展,从最早的静态死亡率模型开始,死亡率模型不断发展为包括时间项的动态预测模型,如Lee-Carter族模型、CBD族模型等.本文对死亡率预测模型的相关文献进行了回顾和梳理.随着动态模型的发展,一些学者从死亡率改善水平入手,发展出一系列死亡率改善模型.另外,随着死亡率研究的深入,多人口死亡率的建模引起了研究者的重视,多人口预测模型迅速发展和完善.随着死亡率模型的研究方法不断丰富和创新,新兴统计学方法(如机器学习等)已经在死亡率建模中有所应用,拟合和预测准确度不断提升.除了经典的建模方法的扩展外,例如小区域人口或数据缺失的人口、高龄人口、相关人口等死亡率建模问题仍值得研究. 展开更多
关键词 动态死亡率 预测 死亡率改善 单人口 人口
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一类非线性FDE整体解的存在性及全局吸引性 被引量:1
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作者 唐先华 庾建设 《数学年刊(A辑)》 CSCD 北大核心 2000年第6期655-666,共12页
本文研究了FDE 整体解的存在性及其零解的全局吸引性,所得结果应用于具有时滞的单种群人口模型 则改进了文[1,2]中的相应结论.
关键词 FDE 整体解 全局吸引性 种群人口模型 非线性 存在性
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Per Capita (PC) versus Per Adult Human Unit Method (PAHUM): A Net Assessment of EU28-Population, Family/Household, Food Consumption and Environmental Impact
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作者 Sumer Hasimoglu Vecihi Aksakal 《Journal of Environmental Science and Engineering(A)》 2015年第7期336-351,共16页
Communication of Lisbon Strategy sets out an integrated package of measures to deliver more sustainable consumption (including food), better environmental protection, correct population and production evaluations by... Communication of Lisbon Strategy sets out an integrated package of measures to deliver more sustainable consumption (including food), better environmental protection, correct population and production evaluations by using appropriate and more meaningful methods. It lays ahead as one of the key challenges for EU28-PC, Adult Equivalent (AE) and conjoint evaluations and implementation are not sufficiently dynamic and forward-looking to drive the performance of methods upwards. Those evaluations do not serve the above purpose. On PC, AE method use overall, voluntary and regulatory instruments are not sufficiently connected and potential synergies among the different instruments are not exploited. Divergent national, international approaches send conflicting signals to producers and consumers. As a result, the full potential of the internal food market of EU28 and its impact on environment are not realized and evaluated on properly identified UNIT basis. Misidentified UNIT for measurement would not give correct results and if one installs his correct assumptions on the wrong unit, the falls results will start following each other. The developed PAHUM-(Copy-right 1989) and policy approach may integrate the potential of the different policy instruments, helping implement them (gender, age, structure and household size) to food consumption and environmental issues. 展开更多
关键词 Per capita per adult human unit adult equivalents food environment.
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Association of NOD1 and NOD2 genes polymorphisms with Helicobacter pylori related gastric cancer in a Chinese population 被引量:9
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作者 Peng Wang Li Zhang +8 位作者 Jian-Ming Jiang Dan Ma Hao-Xia Tao Sheng-Ling Yuan Yan-Chun Wang Ling-Chun Wang Hao Liang Zhao-Shan Zhang Chun-Jie Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期2112-2120,共9页
AIM:To investigate the association between the tag single nucleotide polymorphisms(TagSNPs) of NOD1 and NOD2 and the risk of developing gastric cancer.METHODS:We conducted a hospital-based case-control study including... AIM:To investigate the association between the tag single nucleotide polymorphisms(TagSNPs) of NOD1 and NOD2 and the risk of developing gastric cancer.METHODS:We conducted a hospital-based case-control study including 296 incident gastric cancer patients and 160 gastritis controls.Eight TagSNPs in the NOD1 and NOD2 genes were selected from the Hapmap database using the haploview software and genotyped by the Sequenom MassArray system.The serum levels of anti-Helicobacter pylori(H.pylori) IgG were measured by enzyme-linked immunosorbent assay to indicate H.pylori infection.The odds ratios(OR) and 95% confidence intervals(CI) were calculated by unconditional logistic regression,including sex and age as confounding factors.RESULTS:The NOD1 rs2907749 GG genotype showed a decreased risk for gastric cancer(OR 0.50,95% CI:0.26-0.95,P = 0.04) while the rs7789045 TT genotype showed an increased risk(OR 2.14,95% CI:1.20-3.82,P = 0.01).An elevated susceptibility to gastric cancer was observed in the subjects with H.pylori infection and the NaOD1 rs7789045 TT genotype(OR 2.05,95% CI:1.07-3.94,P = 0.03) or the NOD2 rs7205423 GC genotype(OR 2.52,95% CI:1.05-6.04,P = 0.04).Haplotype analysis suggested that the distribution of AGT(rs2907749,rs2075820 and rs7789045) in NOD1 between the cases and control groups was significantly different(P corrected:0.04),and the diplotype AGT/AGT was associated with an elevated gastric cancer risk(OR 1.98,95% CI:1.04-3.79,P = 0.04).The association of the NOD1 rs7789045 TT genotype and the diplotype AGT/AGT was significant with H.pylori-related diffuse-type gastric cancer(OR 3.00,95% CI:1.38-6.53,P = 0.01;OR 4.02,95% CI:1.61-10.05,P < 0.01,respectively).CONCLUSION:Genetic polymorphisms in NOD1 and NOD2 may interact with H.pylori infection and may play important roles in promoting the development of gastric cancer in the Chinese population. 展开更多
关键词 Gastric cancer NOD1 NOD2 Gene polymorphisms Helicobacter pylori infection
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Association of Interleukin-10 Gene Haplotype with Gastric Cancer in a Chinese Population
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作者 Jing-yuan CUI Hong MA +1 位作者 He WANG Feng-bo SUN 《Clinical oncology and cancer researeh》 CAS CSCD 2010年第4期234-239,共6页
OBJECTIVE Interleukin-10 (IL-10) is a multifunctional cytokine with both immunosuppressive and antiangiogenic functions.Previous studies have reported that IL-10 levels are signifi cantly elevated in patients with g... OBJECTIVE Interleukin-10 (IL-10) is a multifunctional cytokine with both immunosuppressive and antiangiogenic functions.Previous studies have reported that IL-10 levels are signifi cantly elevated in patients with gastric cancer (GC). It has also been confirmed that interindividual variations in IL-10 production are genetically attributed to the polymorphisms of IL-10 gene.Therefore, this study was designed to investigate whether the polymorphisms of IL-10 gene were associated with susceptibility to GC in the Chinese population.METHODS The serum levels of IL-10 were measured by radioimmunoassay. The single nucleotide polymorphisms (SNPs) at positions -1082A/G, -819T/C and -592A/C in the IL-10 gene promoter were analyzed using polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP).RESULTS 220 patients with gastric cancer and 180 healthy controls were included in this study. The serum levels of IL-10 were signifi cantly higher in GC patients than healthy controls (Z = -19.13, P 〈 0.001). Single SNP analysis showed that the -1082G allele, -1082AG and -819CC genotypes significantly increased in patients with GC (P = 0.029, 0.021, 0.039 respectively). In a logistic regression analysis adjusted for age and sex, the -1082AG genotype was associated with an odds ratio of 1.974 (95% CI,1.14-3.391; P = 0.014), and the -819CC genotype with an odds ratio of 2.496 (95% CI, 1.222-5.102; P = 0.012) for GC. Furthermore,haplotype analysis revealed that at least five haplotypes (ATA,ACC, GCC, ACA and ATC) were existent in this population.Also that the GCC haplotype was associated with a signifi cantly increased risk of GC as compared with the ATA haplotype (OR =1.90; 95% CI, 1.11-3.27; P = 0.02).CONCLUSION The results indicate that the gene haplotype of IL-10 may contribute to the susceptibility to GC in the Chinese population. 展开更多
关键词 INTERLEUKIN-10 POLYMORPHISM single nucleotide haplotypes stomach neoplasms
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“食物有限”型泛函微分方程零解的3/2-全局吸引性 被引量:5
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作者 唐先华 庾建设 《中国科学(A辑)》 CSCD 2000年第10期900-913,共14页
研究“食物有限”型泛函微分方程x′(t) + [1 +x(t) ][1 -cx(t) ]F(t,x(·) ) =0 ,t≥0零解的全局吸引性 ,获得了 3 2 型条件 。
关键词 泛函微分方程 全局吸引性 种群人口模型
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