云南丽江树轮δ18O记录的大气环流变化信息

通过对云南玉龙雪山丽江冷杉年轮晚材纤维素氧同位素 (δ¹⁸O) 的分析,建立了1902-2004时段年分辨率的树轮δ¹⁸O序列。将所得序列与相邻的丽江市气象站记录的气候资料对比,分析了树轮δ¹⁸O对气候要素的响应。结果表明,丽江冷杉年轮晚材中的δ¹⁸O与其生长季气候因子密切相关。主要与季风期 (8-10月) 的降水和相对湿度、6-10月总云量、5-6月平均温度显著相关,尤其和总云量相关性最高 (r = -0.45,P = 0.01)。同时,树轮δ¹⁸O年际变化与南亚季风指数、东亚夏季风指数呈反相关关系,并与1-5月南方涛动指数负相关显著,在一定程度上反映了大尺度的大气环流影响。     

利用InSAR数据的格尔木市地表沉降监测

InSAR及其相关技术在城市地面沉降监测中具有独特优势。本文采用2015年12月4日至2018年1月10日间的37景Sentinel-1卫星SAR影像数据,基于InSAR时间序列分析技术,对地处高原的格尔木市市区及其周边进行了地表形变监测。结果表明,基于相干性等指标共提取了252 889个相干点,每平方千米平均有501个相干点,后续经相干点分析计算后掩模去误差较大的点后,实际使用相干点252 035个;格尔木市及其周边郊区的整体沉降速率均在5 mm/a以内,未发现明显的沉降区域或大面积的沉降带,市区南部的沉降速率低于北部。     

残余和现今应力场重迭法预测强震危险时区

以红河断裂带测区为例，用Ｘ射线法测量了测区的古构造残余应力场及其应变能密度场，用有限单元法计算了测区在两种边界条件下的水平最大剪应力场，用实验和理论证明了古构造残余主压应力大小和方向对岩石破坏、破裂扩展和震级的影响。用上述方法预测，松平—南涧、玉溪—开远、普洱为测区内强震危险区段。结合地球自转角速度相对变率的天文观测曲线在时间轴上的外延，预测得１９８９－１９９６、１９９９－２００４、２００７－２０１３、２０１６－２０１８年为测区内强震危险时段。     

同型半胱氨酸水平与脑梗死患者MTHFR基因C677T多态性之间的相关性研究

目的 探讨研究同型半胱氨酸（homocysteine,Hcy）水平与脑梗死患者亚甲基四氢叶酸还原酶（MTHFR）基因C677T的多态性之间的相关性。方法 选择2012年2月~2015年8月期间在笔者医院住院就诊的450例脑梗死患者作为研究组,其中糖尿病患者181例,非糖尿病患者269例,另外选择285例笔者医院门诊部健康的体检人员作为对照组,分别采用焦磷酸测序的方法检测分析MTHFR基因C677T的多态性,并分析各基因型与Hcy水平之间的相关性。结果 脑梗死组与健康对照组的MTHFR基因型分布之间的差异具有统计学意义（P<0.05）,脑梗死组T基因的频率明显比对照组高,差异有统计学意义（χ²=13.67,P=0.00）。脑梗死组患者的Hcy浓度明显高于健康对照组,差异有统计学意义（t=12.71,P=0.00）。脑梗死组患者各MTHFR基因型患者的Hcy水平之间比较,差异有统计学意义（F=17.68,P=0.00）。非糖尿病脑梗死患者的Hcy水平明显高于糖尿病脑梗死患者,差异有统计学意义（t=2.97,P=0.00）,非糖尿病组TT型的Hcy浓度明显高于糖尿病组,CC型的Hcy浓度明显低于糖尿病组,差异均有统计学意义（t=5.67,2.18;P=0.00,0.03）。糖尿病性脑梗死患者和非糖尿病脑梗死患者中,MTHFR基因为TT型的Hcy水平明显高于CC型和CT型,差异均有统计学意义（P<0.05）,而CC型和CT型的Hcy水平之间比较差异无统计学意义（P>0.05）。结论 脑梗死患者比健康人的MTHFR基因C677T的T等位基因频率高,且脑梗死患者的MTHFR基因C677T为TT基因型时血清中Hcy的水平更高,由此判断TT基因型可能是脑梗死发生的危险因素。     

红河断裂带测区古构造残余应力随深度分布X射线测量

以岩体正交各向异性弹性理论为基础,用X射线衍射法,在红河断裂带测区,选用12个大口径钻孔用金刚石钻头钻取的岩芯,测量了岩体中三维宏观残余应力和微观残余应力及其弹性应变能密度随深度的分布,分析了它们沿深度的分布规律。     

Relative humidity history on the Batang–Litang Plateau of western China since 1755 reconstructed from tree-ring δ18O and δD

We measured the annual variation in the stable isotopes of oxygen (δ¹⁸O) and hydrogen (δD) in tree rings of Abies georgei on the Batang–Litang Plateau of western China. Although correlations between tree-ring δ¹⁸O and δD are relatively weak in semi-arid regions, we found a strong correlation between the δ¹⁸O and δD time series from 1755 to 2009 under the wetter environment. Tree-ring δ¹⁸O and δD time series are both significantly and negatively correlated with moisture conditions from June to August, including relative humidity and total precipitation, respectively, from 1960 to 2009. Considering the difference in low-frequency domain between the two isotopes, the relative humidity histories from June to August, reconstructed separately from the tree-ring δ¹⁸O and δD data with instrumental climate data, reveal a persistent drying trend since 1850s, especially since the early 1970s. There is an obvious offset of reconstructed relative humidity from tree-ring δ¹⁸O and δD in the period 1755–1820, despite the strong similarity in their 21-year moving averages. The decreased relative humidity since the 1850s may be associated with the thermal contrast between the sea surface temperature of the Indian Ocean and the Qinghai-Tibetan Plateau, which determines the strength of moisture transfer via the Indian summer monsoon.     

南海北部陆架区海域深水金线鱼的产卵场

根据 1997年 12月至 1999年 6月在南海北部陆架区海域进行的底拖网渔业资源调查的资料 ,统计分析了南海北部陆架区海域深水金线鱼性腺成熟期的组成及分布、季节性变化和水深变化规律。结果表明 ,南海北部陆架区海域深水金线鱼的产卵场位于广东沿海水深 6 0～ 15 0m海区 ,尤其是珠江口外海区的群体更为密集 ;该生殖群体的产卵期较长 ,且分布范围大 ,未见有显著性变化。     

Bioacoustic application on fisheries management in an artificial reefs’ ecological reserve of Bohai Gulf China

Various techniques have been used in marine fishery resources assessment. Among those, acoustic techniques have high efficiency and wide adaptability, and are environment friendly. Therefore, acoustic techniques played a key/indispensable role in the field of ecosystem-based fishery management. Acoustic surveys were conducted during the wet (May) and dry (November) seasons in 2016 in the artificial reefs ecological reserve of Bohai Gulf and a nearby control region to understand the current situation of fishery resources and explore the effectiveness of underwater artificial constructions by a dual-frequency identification sonar (DIDSON) and a scientific split-beam echosounder (120 KHz, Simrad EY60). Fish densities in various seasons and regions showed significant differences and interaction, with a maximum value of 358020.34 ind/n.mile² in the artificial reefs’ region and a minimum value of 71898.35 ind/n.mile² in the control region during the wet season. Fish densities in defined parallel transects revealed a roughly southward migration trend of small-size individuals from wet season to dry season. Single echo detections in the artificial reefs region demonstrated a wider target strength (TS) range (? 60 ~ ? 30 dB vs ? 60 ~ ? 51 dB) and higher mean TS values (? 55.87 dB vs ? 58.31 dB) than the control region both in the wet and dry seasons, which indicated a more complicated and stable fish community structure in the artificial reefs area. The vertical distribution of single echo detections tracked by the echoview post-processing system showed an apparent downward gathering effect. A positive correlation between TS and water depth was discovered from Pearson correlation analysis in the artificial reefs region during the dry season.