Quantitative estimation of social stock for metals Al and Cu in China

Social stock for metal determines secondary or recoverable resources to a certain extent.Top-down analysis method for the studying of metal in social stock was given.Influences of metal consumption under three circumstances,that is keeping constant,varying in a linear trend and in an exponential trend,on one kind of metal’s social stock,recyclable ratio and average age were analyzed.Al-contents and Cu-contents in social stock for China during the period 2006-2009 were calculated.The results reveal that Al-contents and Cu-contents in social stock kept increasing and reached 88.9 million tons and 51.4 millions tons in 2009,respectively,their average recyclable ratios are 1.45% and 0.30%,and the average ages are 4.65 years and 6.89 years,respectively.The recyclable ratios and average ages of Al-contents and Cu-contents in social stock will rise in future along with the decline of the increasing rate of aluminum consumption and copper consumption.

Social structure and space use of Amur tigers(Panthera tigris altaica)in Southern Russian Far East based on GPS telemetry data

To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.

大学新生网络使用时间与网络成瘾的关系：有中介的调节模型

通过整群取样的方法选取北京市某所高校2250名大一新生为测查对象,采用问卷方式探讨了大学新生网络使用时间、网络社交使用占网络使用总时间的比重、网络使用的背景性渴求以及网络成瘾程度之间的关系。基于网络使用满足的相关理论以及渴求的条件反射理论,本研究构建了一个有中介的调节模型,即网络社交使用比重在网络使用时间与网络成瘾之间起调节作用,而且这一调节作用通过网络使用的背景性渴求这一中介变量得以实现。结果显示:(1)大学新生每周上网时间为13.58±8.94小时,网络社交使用占全部上网时间的比重为27.18±18.15%;(2)网络使用时间、网络社交使用比重、网络使用背景性渴求与网络成瘾的五个维度及总分呈显著正相关;(3)网络使用时间以及网络社交使用比重均能够直接正向预测网络成瘾,同时网络社交比重在网络使用时间预测网络成瘾这一关系中起调节作用,即相比较少使用网络社交的被试,较多使用网络社交的群体表现出更高的网络成瘾程度,且网络使用时间对网络成瘾程度的预测作用相对较低;而且网络社交比重的调节作用部分通过网络使用的背景性渴求这一中介变量实现。