幼龄绵羊血清T_4含量的季节和昼夜周期变化

幼龄绵羊血清甲状腺素 (T4)含量的放射免疫测定 (RIA )表明 ,幼龄绵羊年平均含量为 5 8.10 6ng/mL±11.0 5 4ng/mL ,其中冬季昼夜平均含量最高为 72 .5 94ng/mL± 5 .0 48ng/mL ,极明显地高于其他季节 ;春季为 60 .171ng/mL± 8.0 11ng/mL ,极明显地高于夏季均值 47.0 5 5ng/mL± 1.5 41ng/mL(P <0 .0 1) ;秋季为 5 2 .60 2ng/mL± 2 .896ng/mL,与夏季无明显差异 (P >0 .0 5 )。测定结果还表明 ,昼夜周期性变化无明显的差异 (P >0 .0 5 ) ,但白天小绵羊血清中T4含量高于夜晚。

太原市太阳总辐射特征及相关要素分析

用5年滑动平均方法并用最小二乘法建立方程式,计算太阳辐射气候倾向率及日照气候倾向反映太阳辐射的45a变化趋势,用小波分析方法分析太阳总辐射的周期变化规律。结果表明,太原地区的年日照时数减少,年总辐射量呈显著减少趋势,有11a的周期变化,在1981年左右有突变。初步统计能见度低于10km次数在逐年增多。

新疆石河子太阳总辐射特征及相关要素分析

统计了新疆石河子地区1959~2003年太阳总辐射的资料.首先把新疆石河子太阳总辐射资料统一单位,在此基础上用5a滑动平均的统计方法并用最小二乘法建立方程式,计算太阳辐射气候倾向率及日照气候倾向反映太阳辐射的45a变化趋势,用小波分析方法分析太阳总辐射的周期变化规律.结果表明,新疆石河子地区的年日照时数减少,年总辐射量呈显著减少趋势,有11年的周期变化,在1981年左右有突变.初步统计能见度低于10km次数在逐年增多,认为近年来大气混浊度和大气总悬浮粒子浓度的比例增加是引起新疆石河子地区太阳总辐射量下降的原因之一,说明太阳总辐射量的变化与城市发展密切相关.

Reproductive Cycle and Seasonal Variations in Lipid Content and Fatty Acid Composition in Gonad of the Cockle Fulvia mutica in Relation to Temperature and Food

From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.

Seasonal Variation of Biochemical Components in Clam (Saxidomuspurpuratus Sowerby 1852) in Relation to Its Reproductive Cycle and the Environmental Condition of Sanggou Bay, China

Seasonal variation of biochemical components in clam(Saxidomus purpuratus Sowerby 1852) was investigated from March 2012 to February 2013 in relation to environmental condition of Sanggou Bay and the reproductive cycle of clam.According to the histological analysis,the reproductive cycle of S.purpuratus includes two distinctive phases:a total spent and inactive stage from November to January,and a gametogenesis stage,including ripeness and spawning,during the rest of the year.Gametes were generated at a low temperature(2.1℃) in February.Spawning took place once a year from June to October.The massive spawning occurred in August when the highest water temperature and chlorophyll a level could be observed.The key biochemical components(glycogen,protein and lipid) in five tissues(gonad,foot,mantle,siphon and adductor muscle) were analyzed.The glycogen content was high before gametogenesis,and decreased significantly during the gonad development in the gonad,mantle and foot of both females and males,suggesting that glycogen was an important energy source for gonad development.The protein and lipid contents increased in the ovary during the gonad development,demonstrating that they are the major organic components of oocytes.The lipid and protein contents decreased in the testis,implying that they can provide energy and material for spermatogenesis.The results also showed that protein stored in the mantle and foot could support the reproduction after the glycogen was depleted.

Seasonal evolution of circulation and thermal structure in the Yellow Sea

In this paper, the authors used the Princeton Ocean Model (POM) to simulate the seasonal evolu- tions of circulation and thermal structure in the Yellow Sea. The simulated circulation showed that the Yellow Sea Warm Current (YSWC) was a compensation current of monsoon-driven current, and that in winter, the YSWC became stronger with depth, and could flow across the Bohai Strait in the north. Sensitivity and control- ling tests led to the following conclusions. In winter, the direction of the Yellow Sea Coastal Current in the sur- face layer was controlled partly by tide instead of wind. In summer, a cyclonic horizontal gyre existed in the middle and eastern parts of the Yellow Sea below 10 m. The downwelling in upper layer and upwelling in lower layer were somehow similar to Hu et al. (1991) conceptual model. The calculated thermal structure showed an obvious northward extending YSWC tongue in winter, its position and coverage of the Yellow Sea Cold Water Mass in summer.

The seasonal cycle of redistribution of atmospheric mass between continent and ocean in the Northern Hemisphere

Using NCEP/NCAR and ERA-40 reanalyses,we studied the seasonal cycle of redistribution of air mass between continents and oceans over the Northern Hemisphere.Our results demonstrate that air mass in the Northern Hemisphere shifts clearly between continents and oceans when the season cycles.In July,the air mass reaches its lowest over Eurasia and its highest over the Pacific,and the opposite occurs in January.However,a different scenario is observed over the north Atlantic;the accumulated air mass reaches its maximum there in May.The maintenance of the accumulation or loss of air mass in a region is found to be related to the areal mean air mass flux divergence and the difference between precipitation and evaporation in an air column.The zonal-vertical circulations change with season,with the air ascent and decent reversed between land and sea.Besides,there also exists a noticeable difference of water vapor content of the air between continents and oceans,and this difference is season-dependent.Physically,the vapor content is able to significantly affect the atmosphere in absorbing solar short-and earth’s long-wave radiations,hence influencing atmospheric thermal conditions.The land-sea thermal contrasts inclusive of the diabatic heating rate changes their signs with season going on,resulting in the reversal of orientations of the temperature gradient.These thermal forcings not only facilitate the formation of the monsoons but also indirectly induce the seasonal cycle of the air mass exchanging over regions between continents and oceans.

Ionospheric absorption and planetary wave activity in East Asia sector

In this paper, we focus on ionospheric absorption in the East Asia sector, and look for manifestations of atmospheric influences in this area. First, a 4-year historical record of absorption measurement at Beijing is presented. This record was obtained by a sweep frequency technique, in which 27-days periodic variation of the absorption level was found to be dominant, appearing in most seasons except winters. Instead, unusual enhancements of the absorption level appeared in winters (winter anomaly), at the meantime the level varied with periods mainly in the range of 8-12 days. Comparing to 27-days period from the Sun, the shorter period oscillations should be related to planetary wave activities in lower atmosphere. Second, fmin data from 5 mid-latitude ionosondes in Japan were used as an indirect but long-term measurement. With the fmin data covering two solar cycles, disturbances with various periods were found to be active around solar maximum years, but the 8-12 days oscillations always existed in winter, showing seasonal dependence instead of connection to solar activity. These results given in this paper demonstrate seasonal and solar cycle-dependent features of the ionospheric absorption in East Asia sector, and confirm the existence of influence from atmosphere-ionosphere coupling in this area, as well as the relationship between ionospheric winter anomaly and planetary wave activity.