Dynamics of abundance and population structure of sea otters, <Emphasis Type="Italic">Enhydra lutris</Emphasis> L., on the Commander Archipelago and activity of their migrations between Islands

Fluctuations in the abundance of insular groups of sea otters on the Commander Archipelago are analyzed with regard to changes in meteorological conditions. The main factors responsible for the abrupt decline of the Bering Sea group between 2002 and 2004 are discussed. A statistically significant correlation has been revealed between fluctuations of sea otter abundance and the cycles of solar activity in the period since 1992. Changes in the age and sex structure of the insular groups of sea otters are evaluated.     

Update on selective reduction

Over the past 25 years fetal reduction has been utilized to reduce the risks of higher-order multiple pregnancies that have resulted from overly successful infertility therapies. The demographics of multiple pregnancy patients have evolved over the past decade, with increasing proportions coming from IVF as opposed to ovulation induction, being older and a higher proportion with donor eggs. Genetic diagnosis prior to reduction is becoming more common and is very safe in experienced hands. For all starting numbers, including twins, reduction to a lower number of fetuses reduces fetal losses, prematurity, and infant mortality and morbidity. Copyright © 2005 John Wiley & Sons, Ltd.     

消除氯离子对CODcr快速仪法干扰的实验

氯离子浓度高于５００ｍｇ／Ｌ时,对ＣＯＤｃｒ的测定呈混浊干扰,通过加入ＨｇＳＯ４络合氯离子,可消除氯离子含量达２０００ｍｇ／Ｌ的干扰,过量的ＨｇＳＯ４对ＣＯＤｃｒ结果无影响。