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831.
Eze Paez 《Bioethics》2016,30(6):433-439
Emergency contraceptives may sometimes prevent implantation, thereby causing the death of the embryo. According to some positions contrary to abortion, because the embryo is a human animal, there are usually decisive moral reasons not to use them. In this article, I will show that objecting to the use of emergency contraceptives on those grounds is unjustified. If organisms are real existents, then according to the most plausible conception of what is required for a group of cells to compose one, the embryo cannot qualify as a single organism. On the other hand, if organisms are virtual objects, then whether or not the embryo qualifies as one is morally irrelevant. I conclude that even if those positions are right about the morality of abortion, they are not entitled to oppose the use of emergency contraceptives. 相似文献
832.
Catherine A. Lindell 《Restoration Ecology》2008,16(2):197-203
Animals are key members of ecosystems, contributing to processes like pollination, seed dispersal, and herbivory. Incorporating measures of animal behavior into evaluations of restoration success will provide critical information that is not available from animal species composition and richness estimates derived from the documentation of species presence and absence. Behavioral studies will (1) allow comparisons of the habitat quality of target and reference sites based on behaviors that have fitness consequences for organisms; (2) provide valuable information about reasons for differences in habitat quality; (3) identify critical resources that make a site suitable or not for particular species; and/or (4) provide information on the mechanisms through which species contribute to ecosystem functions. When resources for the evaluation of restoration success are available, practitioners should carefully consider the costs and benefits of the different variables they could quantify. In some cases, it may be more important to compare the behavior of one or a few critical animal species that contribute to ecosystem function rather than try to document the presence or absence of all species. 相似文献
833.
Xin Zhao Hieu Tran Holly DeRosa Ryland C. Roderick Amanda C. Kentner 《Genes, Brain & Behavior》2021,20(7):e12755
While there is a strong focus on the negative consequences of maternal immune activation (MIA) on developing brains, very little attention is directed towards potential advantages of early life challenges. In this study, we utilized a polyinosine-polycytidylic acid (poly(I:C)) MIA model to test visual pairwise discrimination (PD) and reversal learning (RL) in mice using touchscreen technology. Significant sex differences emerged in that MIA reduced the latency for males to make a correct choice in the PD task while females reached criterion sooner, made fewer errors, and utilized fewer correction trials in RL compared to saline controls. These surprising improvements were accompanied by the sex-specific upregulation of several genes critical to cognitive functioning, indicative of compensatory plasticity in response to MIA. In contrast, when exposed to a 'two-hit' stress model (MIA + loss of the social component of environmental enrichment [EE]), mice did not display anhedonia but required an increased number of PD and RL correction trials. These animals also had significant reductions of CamK2a mRNA in the prefrontal cortex. Appropriate functioning of synaptic plasticity, via mediators such as this protein kinase and others, are critical for behavioral flexibility. Although EE has been implicated in, delaying the appearance of symptoms associated with certain brain disorders, these findings are in line with evidence that it also makes individuals more vulnerable to its loss. Overall, with the right 'dose', early life stress exposure can confer at least some functional advantages, which are lost when the number or magnitude of these exposures become too great. 相似文献