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1.
The striatum which constitutes most of the forebrain of the early lower vertebrates, controls displays, of which aggression is an integral component in ranking, territory, and courtship. The displays persist in all vertebrates, as does the enlarged and modified striatum. Submissive displays controlled killing in conspecific conflicts. Beginning with the growth of the neocortex in mammals during the Cenozoic period, aggression became more complex, culminating in warfare and genocide. Agonistic/submissive display controls may become inoperative in the chimpanzee, which has the critical amount of intelligence required for genocide, as confirmed by the field observations of Goodall and others.  相似文献   
2.
Sulfur mustard (SM) is an old chemical warfare agent causing blisters (vesicant). Skin toxicity is thought to be partly caused by SM induced DNA damage. SM and the hemi mustard 2-chloroethyl ethyl sulfide (CEES) are bi- and monofunctional DNA alkylating agents, respectively. Both chemicals react especially with N7 guanine. The most abundant adducts are 7-hydroxyethylthioethylguanine for SM (61%) and 7-ethyl thioethylguanine for CEES. Thus, DNA alkylation should serve as a biomarker of SM exposure. A specific monoclonal antibody (2F8) was previously developed to detect SM and CEES adducts at N7 position by means of immunoslotblot (ISB) technique (van der Schans et al. (2004) [16]). Nitrogen mustards (HN-1, HN-2, HN-3) are alkylating agents with structural similarities, which can form DNA adducts with N7 guanine. The aim of the presented work was to modify the van der Schans protocol for use in a field laboratory and to test the cross reactivity of the 2F8 antibody against nitrogen mustards. Briefly, human keratinocytes were exposed to SM and CEES (0–300 μM, 60 min) or HN-1, HN-2, HN-3 (120 min). After exposure, cells were scraped and DNA was isolated and normalized. 1 μg DNA was transferred to a nitrocellulose membrane using a slotblot technique. After incubation with 2F8 antibody, the DNA adducts were visualized with chromogen staining (3,3′-diaminobenzidine (DAB), SeramunGrün). Blots were photographed and signal intensity was quantified. In general, DAB was superior to SeramunGrün stain. A staining was seen from 30 nM to 300 μM of SM or CEES, respectively. However, statistically significant DNA adducts were detected after CEES and SM exposure above 30 μM which is below the vesicant threshold. No signal was observed after HN-1, HN-2, HN-3 exposure. The total hands-on time to complete the assay was about 36 h. Further studies are necessary to validate SM or CEES exposure in blister roofs of exposed patients.  相似文献   
3.
Cryptosporidium is an apicomplexan protozoan that lives in most vertebrates, including humans. Its gp60 gene is functionally involved in its attachment to host cells, and its high level of genetic variation has made it the reference marker for sample typing in epidemiological studies. To understand the origin of such high diversity and to determine the extent to which this classification applies to the rest of the genome, we analysed the patterns of variation at gp60 and nine other nuclear loci in isolates of three Cryptosporidium species. Most loci showed low genetic polymorphism (πS <1%) and similar levels of between‐species divergence. Contrastingly, gp60 exhibited very different characteristics: (i) it was nearly ten times more variable than the other loci; (ii) it displayed a significant excess of polymorphisms relative to between‐species differences in a maximum‐likelihood Hudson–Kreitman–Aguadé test; (iii) gp60 subtypes turned out to be much older than the species they were found in; and (iv) showed a significant excess of polymorphic variants shared across species from random expectations. These observations suggest that this locus evolves under balancing selection and specifically under negative frequency‐dependent selection (FDS). Interestingly, genetic variation at the other loci clusters very well within the groups of isolates defined by gp60 subtypes, which may provide new tools to understand the genome‐wide patterns of genetic variation of the parasite in the wild. These results suggest that gp60 plays an active and essential role in the life cycle of the parasite and that genetic variation at this locus might be essential for the parasite's long‐term success.  相似文献   
4.
In this article I consider why individuals sacrifice their lives for the collective. In the Porgera Valley of highlands Papua New Guinea, young men who are called ‘Rambos’ engage in sustained tribal conflicts due to increasing social inequalities in an area that is supposedly benefiting from socioeconomic development. The opening of the Porgera Gold Mine in 1990 ushered in an era of anticipated benefits that were hoped to transform the lives of the region's subsistence horticulturalists. Yet, anticipated flows of mining money and social benefits have largely failed to materialise. The abjection experienced by young men eventuated into a series of tribal fights, resulting in deaths, displacements, and the destruction of most infrastructure. I examine the fighting and its aftermath in relation to anthropologies of the dark and the good and argue that these polar opposites can hinder more subtle understandings of value plurality among Porgerans.  相似文献   
5.
It has been proposed that human cooperation is unique among animals for its scale and complexity, its altruistic nature and its occurrence among large groups of individuals that are not closely related or are even strangers. One potential solution to this puzzle is that the unique aspects of human cooperation evolved as a result of high levels of lethal competition (i.e. warfare) between genetically differentiated groups. Although between-group migration would seem to make this scenario unlikely, the plausibility of the between-group competition model has recently been supported by analyses using estimates of genetic differentiation derived from contemporary human groups hypothesized to be representative of those that existed during the time period when human cooperation evolved. Here, we examine levels of between-group genetic differentiation in a large sample of contemporary human groups selected to overcome some of the problems with earlier estimates, and compare them with those of chimpanzees. We find that our estimates of between-group genetic differentiation in contemporary humans are lower than those used in previous tests, and not higher than those of chimpanzees. Because levels of between-group competition in contemporary humans and chimpanzees are also similar, these findings suggest that the identification of other factors that differ between chimpanzees and humans may be needed to provide a compelling explanation of why humans, but not chimpanzees, display the unique features of human cooperation.  相似文献   
6.
Plants defend themselves against the attack of natural enemies by using an array of both constitutively expressed and induced defenses. Long-lived woody perennials are overrepresented among plant species that show strong induced defense responses, whereas annual plants and crop species are underrepresented. However, most studies of plant defense genes have been performed on annual or short-lived perennial weeds or crop species. Here I use molecular population genetic methods to survey six wound-inducible protease inhibitors (PIs) in a long-lived woody, perennial plant species, the European aspen (Populus tremula), to evaluate the likelihood of either recurrent selective sweeps or balancing selection maintaining amino acid polymorphisms in these genes. The results show that none of the six PI genes have reduced diversities at synonymous sites, as would be expected in the presence of recurrent selective sweeps. However, several genes show some evidence of nonneutral evolution such as enhanced linkage disequilibrium and a large number of high-frequency-derived mutations. A group of at least four Kunitz trypsin inhibitor genes appear to have experienced elevated levels of nonsynonymous substitutions, indicating allelic turnover on an evolutionary timescale. One gene, TI1, has enhanced levels of intraspecific polymorphism at nonsynonymous sites and also has an unusual haplotype structure characterized by two divergent haplotypes occurring at roughly equal frequencies in the sample. One haplotype has very low levels of intraallelic nucleotide diversity, whereas the other haplotype has levels of diversity comparable to other genes in P. tremula. Patterns of sequence diversity at TI1 do not fit a simple model of either balancing selection or recurrent selective sweeps. This suggests that selection at TI1 is more complex, possibly involving allelic cycling.  相似文献   
7.
Skeletal evidence of nonritual interpersonal trauma in the central Illinois valley is currently limited to the terminal prehistoric period in the region. Sixteen percent of the entire Norris Farms Oneota skeletal sample died violently, presumably because they intruded upon small groups of Mississippians who had not yet abandoned the region. Archaeological evidence of palisades, however, suggests that the region was embroiled in conflict before the Oneota arrived though the skeletal evidence supporting more than ritualized or geographically sporadic cases of scalping or embedded projectiles has been elusive. This study examines the frequency and nature of interpersonal trauma at Orendorf, a Middle Mississippian (AD 1150-1250) site at the northern periphery of the region. Nine percent (N = 25) of all 268 individuals documented at Orendorf suffered warfare-related trauma, including 13 cases of scalping, six instances of decapitation, five individuals with healed cranial blunt force trauma, three projectile point impacts, and eight cases of projectile injuries inferred by the burial context. All of the traumatized individuals were at or above the age of 15 years and males and females were victimized equally. The trauma rate among adults is 16%, which is less than that of the Norris Farms Oneota (34%) but higher than other Mississippian groups in the Southeast. The nature of the injuries is more consistent with attacks by outsiders than codified or ritualized intragroup violence.  相似文献   
8.
ABSTRACT:?

Referee: Dr. Catharina Y. W. Ang, National Center Toxicology Research, HFT-230, FDA, 3900 NCTR Road, Jefferson, AR 72079

Control of the foodborne pathogens Escherichia coli O157:H7, Salmonella typhimurium, Staphylococcus aureus, and Listeria monocytogenes during sufu fermentation was evaluated. Before fermentation, pathogens were inoculated onto tofu (substrate for sufu) at 5 log cfu/g or 3 log cfu/g, and starter culture (Actinomucor elegans) was inoculated at 3 log cfu/g. After 2 days of fermentation at 30°C, the four pathogens reached 7 to 9 log cfu/g, and the mold count reached 6 to 7 log cfu/g. After fermentation, sufu samples were aged in a solution of 10% alcohol + 12% NaCl. After 1 month of aging, the total bacterial count was 6 to 7 log cfu/g, but all foodborne pathogens and mold were reduced to nondetectable levels. The total bacterial count decreased after aging for 2 months and 3 months, but the differences were not significant (P>0.05) compared with the count after 1 month. Microorganism in experimental sufu from different aging periods and in commercial sufu were compared. A total of 270 isolates were purified and identified by the BBL Crystal Identification System. From the experimental sufu samples, 49 Bacillus spp. (20.4%), 167 Enterococcus spp. (69.6%), 6 Shewanella putrefaciens (2.4%), and 18 miscellaneous Gram-negative bacilli (7.5%) were identified. From commercial sufu samples, 17 Bacillus. spp. (56.7%), 2 Enterococcus durans (6.7%), 5 miscellaneous Gram-negative bacilli (16.7%), 5 Corynbacterium aquaticum (16.7%), and 1 Shewanella putrefaciens (3.3%) were obtained. Although the longer aging period did not significantly decrease the total bacterial count, it may help in the development of sufu flavor. This study showed that sufu fermentation and aging can control common foodborne pathogens, so sufu is a safe product even though its preparation does not include pasteurization.  相似文献   
9.
This paper reports upon a series of recent developments in New Guinea highlands warfare. Building upon existing literature highlighting the deep influence of modernity within this context, we draw attention to two particular developments yet to be reported in the literature and which appear to be of special significance. Through an analysis of Aiya warfare, Southern Highlands Province, Papua New Guinea, we document the direct and increasing involvement of women within warfare, as well as the important role played by mobile phones used by warriors to communicate before and during fighting. These two developments are situated in relation to broader shifts currently reshaping Melanesian sociality, namely, the ambivalent and fraught position of women within an emergent PNG society, as well as the rapid diffusion of mobile phone technology throughout the region.  相似文献   
10.
Bacillus anthracis is a Gram-positive, spore-forming bacterium representing the etiological agent of acute infectious disease anthrax, a lethal but rare disease of animals and humans in nature. With recent use of anthrax as a bioweapon, a number of techniques have been recently developed and evaluated to facilitate its rapid detection of B. anthracis in the environment as well as in point-of-care settings for humans suspected of exposure to the pathogen. Complex laboratory methods for B. anthracis identification are required since B. anthracis has similarities with other Bacillus species and its existence in both spore and vegetative forms. This review discusses current challenges and various improvements associated with anthrax agent detection.  相似文献   
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