北方季风边缘区洞穴石笋δ~(18)O序列预测初步研究

基于时域组合模型建立了中国北方季风边缘区万象洞及黄爷洞石笋&delta;~(18)O时间序列的动态模型,并对未来20年的降水变化趋势进行了预测。研究结果表明,时域组合模型较好地提取了时间序列的周期信息,用其拟合实测数据精度较高;用其预测时间序列的变化情况,和现代气象观测记录相吻合,具有一定的可信度。同时通过中国北方季风边缘区树轮的预测结果对比显示,该地区在2012~2013年前后降水最少,随后20年里将呈现先升后降的变化趋势。</p

桥接治疗对急性脑梗死患者神经元特异性烯醇化酶、S100钙结合蛋白B、胶质纤维酸性蛋白的影响 Effect of Bridging Therapy on Neuron-Specific Enolase, S100 Calcium-Binding Protein B, Glial Fibrillary Acidic Protein in Patients with Acute Cerebral Infarction

目的 探讨桥接治疗对前循环大血管闭塞急性脑梗死患者血清神经损伤相关生化标志物的影响以及临床疗效，为急性脑梗死治疗方式的选择提供参考依据。 方法 回顾性分析2018年10月—2020年6月前循环大血管闭塞的急性脑梗死患者的病历资料，根据是否采取桥接治疗分为对照组（静脉溶栓组）和观察组（桥接治疗组）。统计两组在治疗后24 h、14 d的治疗有效（NIHSS评分下降≥4分或NIHSS评分0分）率，治疗后30 d、90 d及180 d的良好预后 （mRS评分≤2分）率及日常生活能力自理（Barthel指数＞60分）率，住院期间脑出血发生率，治疗前以及治疗后3 d、7 d及14 d神经元特异性烯醇化酶（neuron-specific enolase，NSE）、S100钙结合蛋白B（S100 calcium-binding protein B，S100B）及胶质纤维酸性蛋白（glial fibrillary acidic protein，GFAP）水平。采用基于混合效应的logistic回归模型、线性混合效应模型进行预后指标的统计分析。 结果 多因素分析结果显示：观察组的治疗有效率是对照组的3.35倍（OR 3.35，95%CI 1.10～10.13，P=0.041）；观察组的良好预后率是对照组的4.12倍（OR 4.12，95%CI 1.14～14.82，P=0.035）；观察组的日常生活能力自理率与对照组相当（OR 1.47，95%CI 0.28～7.68，P=0.648）；观察组与对照组脑出血发生率差异无统计学意义（7.4% vs. 8.7%，P=1.000）；观察组NSE、S100B、GFAP水平低于对照组，差异具有统计学意义（P<0.001）。 结论 对于前循环大血管闭塞的急性脑梗死患者，与单纯静脉溶栓相比，桥接治疗可显著降低患者NSE、S100B及GFAP水平，提高临床疗效。 Abstract: Objective To explore the effect of bridging therapy on the related biochemical markers of serum nerve injury in acute cerebral infarction patients with anterior circulation large vessel occlusion and its clinical efficiency, in order to provide evidence for the selection of treatment methods for acute cerebral infarction. Methods The patients with acute cerebral infarction with occlusion of large vessels in anterior intracranial circulation from October 2018 to June 2020 were analyzed retrospectively. According to whether bridging therapy was taken, they were divided into control group (intravenous thrombolysis group) and observation group (bridging therapy group). The treatment effective (NIHSS score decreased by≥4 points or NIHSS score of 0 point) rate between the two groups at 24 h and 14 d after treatment was analyzed. The good prognosis (mRS score≤2 points) rate and self-care (Barthel index>60) rate of normal living ability between two groups at 30 d, 90 d and 180 d after treatment, the incidence of intracerebral hemorrhage during hospitalization, and the related biochemical markers of serum nerve injury [neuron-specific enolase (NSE), S100 calcium-binding protein B (S100B) and glial fibrillary acidic protein (GFAP)] before and at 3 d, 7 d and 14 d after treatment were also analyzed. Logistic regression model based on mixed effects and linear mixed effects model were used for statistical analysis of prognostic indicators. Results Multivariate analysis showed that the treatment effective rate of the observation group was 3.35 times higher than that of the control group (OR 3.35, 95%CI 1.10-10.13, P=0.041). The good prognosis rate of the observation group may be 4.12 times higher than that of the control group (OR 4.12, 95%CI 1.14-14.82, P=0.035). The self-care rate of normal living ability in the observation group was similar to that in the control group (OR 1.47, 95%CI 0.28-7.68, P=0.648). There was no significant difference in the incidence of intracerebral hemorrhage between the observation group and the control group (7.4% vs. 8.7%, P=1.000). The levels of NSE, S100B and GFAP in the observation group were lower than those in the control group, and the differences were statistically significant (P<0.001). Conclusions Compared with simple intravenous thrombolysis, bridging therapy can significantly reduce NSE, S100B and GFAP in acute cerebral infarction patients with anterior circulation large vessel occlusion, and improve clinical efficiency

西安东郊 S5土壤中 AgSO4等矿物的发现与研究

根据西安东郊任家坡黄土剖面中第 5 层古土壤样品的电子显微镜观察和能谱分析, 在该层古土壤中发现了极少见的能够指示典型干旱气候环境的 AgSO4 矿物和钼矿物等. 次 生银矿物一般呈现椭球形结晶粒状形态, 具有孔洞和裂隙化学沉淀结晶的特点, 钼矿物具 有胶体物质的特点. 次生银矿物有两种类型, 一是 AgSO4矿物, 二是氧化银矿物. 次生银、 钼和钴矿物与新生粘土矿物及 Fe2O3和 Al2O3的明显迁移指示该层土壤发育时经历了较为强 烈的化学风化和矿物分解作用, 银、 钼和钴能够从原生矿物中释放出来, 当时西安地区降水 量丰富, 达到了酸性化学风化阶段. 在西安地区 S5 下部分层古土壤发育末期, 出现了由温 暖湿润季风气候向非季风干旱气候的大变化. 在比 CaSO4 还易于溶解的 AgSO4 形成时期, 关中平原为非季风干旱气候, 强烈的蒸发造成了土壤水溶液中 SO42的富集和 AgSO4 的形 成. 当时东亚夏季风活动极弱, 一般不能越过秦岭到关中平原地区, 那时西安地区年降水 量为 300 mm 以下, 比现今兰州地区的气候还要冷干

西安蓝田S_4古土壤剖面中针铁矿富集层与土壤古水分研究

利用野外调查与观察、电镜观察和X-射线衍射法,对西安市蓝田县白鹿塬东端安村北约1km的第四纪黄土-古土壤剖面(34&deg;17&#39;N, 109&deg;32&#39;E)中第4层古土壤(S_4)的铁锰结核样品进行了实验分析。整个S_4古土壤风化剖面厚度为5.6m,粘化层的厚度为1.5m,在S_4古土壤层下部5.0?5.6m深度范围发现了具有指示当时土壤水分含量、地下水富集、水分循环等作用的针铁矿(a-FeO(OH))与铁锰结核富集层。针铁矿呈褐黄色薄膜分布于土体表面。含针铁矿的铁锰结核呈黑褐色球形,电镜下主要呈颗粒状、球形和呈菊花形等形态。针铁矿和铁锰结核呈层分布在同一层位,形成于当时的地下水位附近。在铁锰结核样品中,针铁矿含量为0.9%~3.3%,粘土矿物伊利石含量为6.0% ~ 15.5%,高岭石含量为2% -5%,石英含量为61.1%~66.6%, 斜长石含量10% ~ 16.4%, 钾长石含量3.8%-6.0%。针铁矿与铁锰结核的发育和迁移深度指示,在西安蓝田安村附近S_4古土壤发育时期,年降水量至少为900mm,且重力水分布深度达到了5.6m,5.6m深度范围内的含水量大于25%,在针铁矿和铁锰结核发育层位,含水量接近饱和。当时土壤水分含量很充足,土壤水分平衡为正,有较多水分补给地下水,适于茂盛森林植被发育。研究显示,组成铁锰结核的物质成分来自S_4古土壤粘化层中高价铁锰氧化物迁移,并随着地下水位的升降而发生还原和氧化聚集形成。</p

中国油茶生产区域比较优势分析与影响因素研究Comparative advantage analysis and influencing factors of Camellia oleifera production areas in China

为促进油茶产业高质量发展，丰富我国食用植物油供给体系，根据2010—2020年的数据，采用综合比较优势法分析我国16个油茶生产区域的比较优势，对其影响因素进行研究，并提出相应的提质增产的建议。结果表明：2010—2020年，中国油茶生产规模呈现出东西部增长，中部下降的特征；中国16个油茶生产区域生产规模优势总体波动较小，效率优势呈先降后升趋势，效益优势、综合比较优势总体呈下跌状态。根据油茶生产区域的规模、效率、效益优势情况，将16个油茶生产区域划分为“三高省区”“规模优势省区”“效率优势省区”等7种类型，其中湖南、江西、浙江属于“三高省区”，广东、广西、福建属于“规模优势和效率优势双高省区”，云南属于“规模优势省区”，湖北、海南、江苏属于“效率优势和效益优势双高省区”，贵州、陕西属于“效率优势省区”，安徽属于“效益优势省区”，四川、重庆、河南属于“三低省区”。各省区油茶生产受自然资源禀赋、科技水平、市场、政策等因素影响，建议通过优化种植区域布局、完善油茶市场体制、加速新品种研发、提高机械化程度等措施进一步缩小油茶生产区域间的优势差异。In order to promote the high-quality development of the Camellia oleifera industry and enrich China′s edible vegetable oil supply system, according to data from 2010 to 2020, the comparative advantage of 16 Camellia oleifera production areas in China was analyzed using the comprehensive comparative advantage method, and the influencing factors were studied. Corresponding suggestions to improve quality and increase production were proposed. The results showed that from 2010 to 2020, the production of Camellia oleifera in China showed the characteristics of "increasing in the East and West", "decreasing in the Middle". The scale advantage of China′s 16 Camellia oleifera production areas fluctuated slightly in general, the efficiency advantage first decreased and then increased, and the benefit advantage and comprehensive advantage generally declined. According to the scale, efficiency and benefit advantages of Camellia oleifera production areas, the 16 Camellia oleifera production provinces(regions) were divided into seven types, in which Hunan, Jiangxi, and Zhejiang belonged to the "Three High Provinces"; Guangdong, Guangxi, and Fujian belonged to the "Dual High Provinces with Scale and Efficiency Advantages"; Yunnan belonged to the "Scale Advantage Province"; Hubei, Hainan, and Jiangsu belonged to the "Dual High Provinces with Efficiency and Benefit Advantages"; Guizhou and Shaanxi belonged to the "Efficiency Advantage Province"; Anhui belonged to the "Benefit Advantage Province"; Sichuan, Chongqing, and Henan belonged to the "Three Low Provinces". The production in the Camellia oleifera was influenced by natural resource endowment, technological level, market factors, and policy factors. The advantageous differences between production areas can be reduced by optimizing the layout of planting areas, improving the Camellia oleifera market system, accelerating the development of new varieties, and improving the degree of mechanization