Genetic control of social organization in an ant

A central issue in evolutionary biology is the extent to which complex social organization is under genetic control. We have found that a single genomic element marked by the protein-encoding gene Gp-9 is responsible for the existence of two distinct forms of social organization in the fire ant Solenopsis invicta. This genetic factor influences the reproductive phenotypes and behavioral strategies of queens and determines whether workers tolerate a single fertile queen or multiple queens per colony. Furthermore, this factor affects worker tolerance of queens with alternate genotypes, thus explaining the dramatic differences in Gp-9 allele frequencies observed between the two social forms in the wild. These findings reveal how a single genetic factor can have major effects on complex social behavior and influence the nature of social organization.     

Toxic effect of systemic administration of low doses of the plasticizer di-(2-ethyl hexyl) phthalate [DEHP] in rats

A spreadsheet model of a circle breathing system and a 70-kg anaesthetised 'standard man' has been used to simulate the first 20 min of low-flow anaesthesia with halothane, enflurane, isoflurane, sevoflurane and desflurane in oxygen. It is shown that, with the fresh-gas flow set initially equal to the total ventilation and the fresh-gas partial pressure to 3 MAC, the end-expired partial pressure can be raised to 1 MAC in 1 min with desflurane and sevoflurane, 1.5 min with isoflurane, 2.5 min with enflurane and 4 min with halothane. Sequences of lower fresh-gas flow and partial pressure settings are given for then maintaining 1 MAC end-expired partial pressure, with a minimum usage of anaesthetic, e.g. 13 ml of liquid desflurane in 20 min (of which only 33% is taken up by the patient) if the minimum acceptable flow is 11.min-1, or 8 ml (with 57% in the patient) if the minimum is 250 ml.min-1.     

纺织业优化潜能

全球化对大多数人来说已成为一个时髦名词,不过在纺织业看来,这个词语早在多年前就是日常商务活动中的一部分了。通常一件令人满意的衣服在到达顾客手中之前,早就在全球兜过一大圈了。站在消费者的立场,介绍并分析了整个纺织链。     

可廉价染色的粘胶纤维

这篇文章是关于Ｄａｎｕｆｉｌ深染型纤维,一种与阴离子染料有很高亲和力的新再生纤维,因此可最大限度地减少染色助剂用量。这种新型纤维因其更符合经济学和生态学的原因而引人注目,因为它减少了水和盐的用量。一浴去可用于该纤维的混纺物,染色生产率要高得多。