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1.
Rafael Alarcón-Medina 《Dialectical Anthropology》2018,42(3):293-308
In recent years, the US government has intensified the deportation of undocumented Mexican migrants, some of them with long life trajectories in the USA. With weak family networks in their communities of origin and sometimes none at all, many deportees choose to stay in cities along the US-Mexico border, joining the army of underpaid, low-skilled, and informal urban workers. Some take advantage of their transnational experience to earn a better income; within this context, the call center industry is an economic sector that profits from the language facility and sociocultural skills deported populations bring with them from their years spent living in the USA. This paper addresses the working conditions among call center workers in Mexico, with a focus in Tijuana City in the Mexican Northwest. In particular, I explore how migration, deportation, and call center labor produces what I call informational return, a process in which the convergence of culture, deportation, and digital media plays a key role in the constitution of a transnational digital worker. 相似文献
2.
Todd Meyers 《Culture, medicine and psychiatry》2014,38(2):182-196
The problem of lying as a feature of medication compliance has been well documented in anthropological and clinical literatures. Yet the role of the lie—its destabilizing effects on the continuity of drug treatment and therapy, as a technology of drug misuse, or as a way to understand the neuro-chemical processes of treatment (pharmacotherapy “tricking” or lying to the brain)—has been less considered, particularly in the context of opioid replacement therapy. The following paper is set against the backdrop of a three-year study of adolescents receiving a relatively new drug (buprenorphine) for the treatment of opiate dependency inside and outside of highly monitored treatment environments in the United States. Lies give order not only to the experience of addiction but also to the experience of therapy as well. In order to better understand this ordering of experience, the paper puts the widely discussed conceptual duality of the pharmakon (healing and poison) in conversation with a perilously overlooked subject in the critical study of pharmacotherapy, namely the pharmakos or the personification of sacrifice. The paper demonstrates how the patient-subject comes to represent therapeutic promise by allowing for the possibility of (and often performing) deceit. 相似文献
3.
Rachael L. Brown 《Biology & philosophy》2013,28(6):933-955
Traditional accounts of the role of learning in evolution have concentrated upon its capacity as a source of fitness to individuals. In this paper I use a case study from invasive species biology—the role of conditioned taste aversion in mitigating the impact of cane toads on the native species of Northern Australia—to highlight a role for learning beyond this—as a source of evolvability to populations. This has two benefits. First, it highlights an otherwise under-appreciated role for learning in evolution that does not rely on social learning as an inheritance channel nor “special” evolutionary processes such as genetic accommodation (both of which many are skeptical about). Second, and more significantly, it makes clear important and interesting parallels between learning and exploratory behaviour in development. These parallels motivate the applicability of results from existing research into learning and learning evolution to our understanding the evolution of evolvability more generally. 相似文献
4.
Smith JE 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2012,43(2):338-348
This paper considers the relationship between diet, embodiment, nature and virtue in several seventeenth-century natural philosophers, all of whom sought to overcome or to radically reform inherited ideas about the self as a hylomorphic compound of form and matter, but who nonetheless were not entirely ready to discard the notion that the self is intimately united with the body. One implication of this intimate union, for them, is that what one does with the body, including what one puts into it, is directly relevant to the supreme end of achieving a virtuous life. I thus consider food—its preparation and its consumption—as a link between natural and moral philosophy in the early modern period, showing in particular the parallels between the search for the diet that is ‘natural to man’, on the one hand, and the project of establishing rules of virtue on the other. Key to discerning these parallels, I argue, is an understanding of early modern ideas about diet and eating as rooted in the Stoic notion of oikeiôsis, which may be translated as ‘assimilation’ or ‘appropriation’, and which, as recent work by Lisa Shapiro has shown, played an important role in early modern ideas about a bodily contribution to the human good. The most general thesis is that dietary questions were far more important in early modern philosophy than has yet been recognized: nearly every prominent natural philosopher was preoccupied with them. A narrower thesis is that this parallelism between natural philosophy and moral philosophy is reflected in the conception of cooking as both a fundamental physiological process (‘coction’) as well as the most basic form of social existence. 相似文献
5.
Amir Abdoli 《生物学前沿》2014,9(2):151-160
Toxoplasma gondii is an intracellular parasite involved in the etiology of various behavioral and hormonal alterations in humans and rodents. Various mechanisms, including induction changes of testosterone production, have been proposed in the etiology of behavioral alterations during T. gondii infection. However, controversy remains about the effects of T. gondii infection on testosterone production; in some studies, increased levels of testosterone were reported, whereas other studies reported decreased levels. This is a significant point, because testosterone has been shown to play important roles in various processes, from reproduction to fear and behavior. This contradiction seems to indicate that different factors--primarily parasite strains and host variations--have diverse effects on the intensity of T. gondii infection, which consequently has diverse effects on testosterone production and behavioral alterations. This paper reviews the role of parasite strains, host variations, and intensity of T. gondii infection on behavioral alterations and testosterone production, as well as the role of testosterone in the etiology of these alterations during toxoplasmosis. 相似文献
6.
《Ethology and sociobiology》1986,7(3-4):379-395
A bewildering variety of social patterns can be described and analyzed as manifestations of ostracism and social rejection. Ostracism can be viewed as a coerced or involuntary rupture of social bonds, as distinguished from voluntary exit; both appear to be characteristic ways that animals use in relating to other members of the group. Based on Albert O. Hirschman's Exit, Voice and Loyalty, a general theoretical framework can be built on the realization that ostracism is far from a strange aberration—but that its excesses strike most moderns as uncivilized. This analysis presumes that active participation, flight, and bonding are general categories intrinsic to social behavior. It follows that, in different social contexts, the implications of ostracism vary greatly. Modern democratic systems, in which voluntary exit remains a possibility, resemble our hominid past more closely than authoritarian societies that place individuals in the unenviable position of being trapped in silence (with no legitimate right to exercise political voice, yet no possibility of escape). At the risk of Charges of valuative bias, the argument is made that democratic regimes may be—all things equal—closer to the center of our species-typical range of behavior than other kinds of centralized states or governmental systems. 相似文献
7.
N. V. Karapetyan Yu. V. Bolychevtseva N. P. Yurina I. V. Terekhova V. V. Shubin M. Brecht 《Biochemistry. Biokhimii?a》2014,79(3):213-220
The structural organization of photosystem I (PSI) complexes in cyanobacteria and the origin of the PSI antenna long-wavelength chlorophylls and their role in energy migration, charge separation, and dissipation of excess absorbed energy are discussed. The PSI complex in cyanobacterial membranes is organized preferentially as a trimer with the core antenna enriched with long-wavelength chlorophylls. The contents of long-wavelength chlorophylls and their spectral characteristics in PSI trimers and monomers are species-specific. Chlorophyll aggregates in PSI antenna are potential candidates for the role of the long-wavelength chlorophylls. The red-most chlorophylls in PSI trimers of the cyanobacteria Arthrospira platensis and Thermosynechococcus elongatus can be formed as a result of interaction of pigments peripherally localized on different monomeric complexes within the PSI trimers. Long-wavelength chlorophylls affect weakly energy equilibration within the heterogeneous PSI antenna, but they significantly delay energy trapping by P700. When the reaction center is open, energy absorbed by long-wavelength chlorophylls migrates to P700 at physiological temperatures, causing its oxidation. When the PSI reaction center is closed, the P700 cation radical or P700 triplet state (depending on the P700 redox state and the PSI acceptor side cofactors) efficiently quench the fluorescence of the long-wavelength chlorophylls of PSI and thus protect the complex against photodestruction. 相似文献
8.
T S Yagura Z Kazimierczuk D Shugar J P Miller 《Biochemical and biophysical research communications》1980,97(2):737-743
Analogs of cyclic AMP lacking the 6-amino group—9-β-D-ribofuranosylpurine cyclic 3′,5′-phosphate (I)—or the 1- and 3-nitrogens as well as the 6-amino group—1-β-D-ribofuranosylbenzimidazole cyclic 3′,5′-phosphate (II)—were effective activators of both type I (cAKI) and type II (cAKII) isozymes of cAMP-dependent protein kinase. An analog with a pyrimidine ring fused to the benzimidazole ring system of II—3-β-D-ribofuranosyl-8-aminoimidazo[4,5-g]-quinazoline cyclic 3′,5′-phosphate (III)—was equipotent to I or II as an activator of cAKII but only as potent as I or II as an activator of cAKII. The results show that neither cAKI nor cAKII requires the 6-amino group and that they may have different sensitivities to the effects of alterations in the electron distribution in the pyrimidine ring. 相似文献
9.
Geographic variation can be an indicator of still poorly understood evolutionary processes such as adaptation and drift. Sensory systems used in communication play a key role in mate choice and species recognition. Habitat-mediated (i.e. adaptive) differences in communication signals may therefore lead to diversification. We investigated geographic variation in echolocation calls of African horseshoe bats, Rhinolophus simulator and R. swinnyi in the context of two adaptive hypotheses: 1) James’ Rule and 2) the Sensory Drive Hypothesis. According to James’ Rule body-size should vary in response to relative humidity and temperature so that divergence in call frequency may therefore be the result of climate-mediated variation in body size because of the correlation between body size and call frequency. The Sensory Drive Hypothesis proposes that call frequency is a response to climate-induced differences in atmospheric attenuation and predicts that increases in atmospheric attenuation selects for calls of lower frequency. We measured the morphology and resting call frequency (RF) of 111 R. simulator and 126 R. swinnyi individuals across their distributional range to test the above hypotheses. Contrary to the prediction of James’ Rule, divergence in body size could not explain the variation in RF. Instead, acoustic divergence in RF was best predicted by latitude, geography and climate-induced differences in atmospheric attenuation, as predicted by the Sensory Drive Hypothesis. Although variation in RF was strongly influenced by temperature and humidity, other climatic variables (associated with latitude and altitude) as well as drift (as suggested by a positive correlation between call variation and geographic distance, especially in R. simulator) may also play an important role. 相似文献
10.
Alex Mesoudi 《Evolutionary biology》2016,43(4):481-497
The last two decades have seen an explosion in research analysing cultural change as a Darwinian evolutionary process. Here I provide an overview of the theory of cultural evolution, including its intellectual history, major theoretical tenets and methods, key findings, and prominent criticisms and controversies. ‘Culture’ is defined as socially transmitted information. Cultural evolution is the theory that this socially transmitted information evolves in the manner laid out by Darwin in The Origin of Species, i.e. it comprises a system of variation, differential fitness and inheritance. Cultural evolution is not, however, neo-Darwinian, in that many of the details of genetic evolution may not apply, such as particulate inheritance and random mutation. Following a brief history of this idea, I review theoretical and empirical studies of cultural microevolution, which entails both selection-like processes wherein some cultural variants are more likely to be acquired and transmitted than others, plus transformative processes that alter cultural information during transmission. I also review how phylogenetic methods have been used to reconstruct cultural macroevolution, including the evolution of languages, technology and social organisation. Finally, I discuss recent controversies and debates, including the extent to which culture is proximate or ultimate, the relative role of selective and transformative processes in cultural evolution, the basis of cumulative cultural evolution, the evolution of large-scale human cooperation, and whether social learning is learned or innate. I conclude by highlighting the value of using evolutionary methods to study culture for both the social and biological sciences. 相似文献
11.
Lauren Cubellis 《Culture, medicine and psychiatry》2018,42(3):628-646
What does it mean to offer care when the act of caring is wounding to its giver? For peer specialists—individuals with lived experience as patients in the psychiatric system—this question shapes how they use their own histories to provide support for individuals experiencing psychiatric crisis. Peer support is unique in the way it draws on empathetic resonance and depends on carefully deployed vulnerability; where one connects with others through the recognition of shared experience and mutual hurt. For peers, care works when this guidance, reassurance, and "being with"—all of which draw upon their own stories of traumatic history and variegated suffering—mitigate the present crisis being experienced by another. Drawing on twenty-eight months of fieldwork with a peer-staffed crisis respite center in the eastern United States, I argue that the peer specialist becomes the embodiment of a novel intersection of intimacy and compensation; one that poses vulnerability not as a consequence, casualty, or risk factor in the commodification of care, but as its principle vector of resonance and the assumption on which it is based. For peers, care that works—in that it creates a mutual resonance for the recipient—becomes simultaneously care that wounds its giver. 相似文献
12.
Choosing a Mate in a Cocktail Party‐Like Situation: The Effect of Call Complexity and Call Timing between Two Rival Males on Female Mating Preferences in the Túngara Frog Physalaemus pustulosus
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Zaida Tárano 《Ethology : formerly Zeitschrift fur Tierpsychologie》2015,121(8):749-759
Signal detection, recognition, and localization are hampered when multiple signalers coincide in time and space, a problem known as ‘cocktail party effect’. In many taxa, senders utter complex calls consisting of two or more elements which often vary in the ease with which they can be assessed in different signaling environments. Receivers’ selective attention to different cues may increase the probability of correctly assigning a signal to its source (localization) in face of conspecific interference. Túngara frogs, Physalaemus pustulosus, produce complex calls consisting of an initial whine, followed by zero up to seven broad‐banded, amplitude‐modulated chucks. Under ideal conditions (without interference or noise), females prefer whines followed by chucks over whines alone, but the preference is not linear; females do not discriminate between whines with one or two chucks. When whines lack chucks, call overlap elicits random responses in females, with no preference for leading calls. In this study, I explored the combined effect of call timing and call complexity on female preferences in a two‐choice paradigm—a simplification of the cocktail party scenario. I tested the hypothesis that the effect of call overlap can be reduced when the calls of one of the two rivals have chucks, specifically more chucks than those of the rival. I gave females a choice between whines alone and with chucks (one or two) presented at three time relations (alternated, abutted, and partially overlapped) and two emission orders (whine with less chucks leading and whine with more chucks leading). I found that the preference for one chuck over no chuck was preserved in all the experimental treatments, but when a w + 2chk preceded a w + chk, either overlapped or abutted, a preference existed for the whine with more chucks. Therefore, an interaction between call order and the number of chucks was obtained. The results only partially supported the hypothesis, and call order emerges as an opportunistic component of signaling in P. pustulosus. 相似文献
13.
Alexander Eletsky Karolina Michalska Scott Houliston Qi Zhang Michael D. Daily Xiaohui Xu Hong Cui Adelinda Yee Alexander Lemak Bin Wu Maite Garcia Meagan C. Burnet Kristen M. Meyer Uma K. Aryal Octavio Sanchez Charles Ansong Rong Xiao Thomas B. Acton Joshua N. Adkins Gaetano T. Montelione Andrzej Joachimiak Cheryl H. Arrowsmith Alexei Savchenko Thomas Szyperski John R. Cort 《PloS one》2014,9(7)
Bacterial species in the Enterobacteriaceae typically contain multiple paralogues of a small domain of unknown function (DUF1471) from a family of conserved proteins also known as YhcN or BhsA/McbA. Proteins containing DUF1471 may have a single or three copies of this domain. Representatives of this family have been demonstrated to play roles in several cellular processes including stress response, biofilm formation, and pathogenesis. We have conducted NMR and X-ray crystallographic studies of four DUF1471 domains from Salmonella representing three different paralogous DUF1471 subfamilies: SrfN, YahO, and SssB/YdgH (two of its three DUF1471 domains: the N-terminal domain I (residues 21–91), and the C-terminal domain III (residues 244–314)). Notably, SrfN has been shown to have a role in intracellular infection by Salmonella Typhimurium. These domains share less than 35% pairwise sequence identity. Structures of all four domains show a mixed α+β fold that is most similar to that of bacterial lipoprotein RcsF. However, all four DUF1471 sequences lack the redox sensitive cysteine residues essential for RcsF activity in a phospho-relay pathway, suggesting that DUF1471 domains perform a different function(s). SrfN forms a dimer in contrast to YahO and SssB domains I and III, which are monomers in solution. A putative binding site for oxyanions such as phosphate and sulfate was identified in SrfN, and an interaction between the SrfN dimer and sulfated polysaccharides was demonstrated, suggesting a direct role for this DUF1471 domain at the host-pathogen interface. 相似文献
14.
Jie Yang 《Culture, medicine and psychiatry》2016,40(1):100-123
Negative emotions such as anger, and community responses to their expression are culturally and politically conditioned, including by dominant medical discourse on anger’s somatic and psychic effects. In this article I examine local genres of anger expression in Beijing, China, particularly among marginalized workers, and address culturally specific responses to them. Through majie (rant), xiangpi ren (silenced rage), and nande hutu (muddledness as a more difficult kind of smartness), workers strategically employ anger to seek redress for injustices and legitimate their moral indignation while challenging official psychotherapeutic interventions. Those who seek to regulate anger, mostly psychosocial workers acting as arm’s-length agents of the state, use mixed methods that draw on Western psychotherapy and indigenous psychological resources to frame, medicalize or appease workers’ anger in the name of health and social stability. I demonstrate how the two processes—anger expression and responses to it—create tensions and result in an ambiguous and multivalent social terrain which Chinese subjects must negotiate and which the state attempts to govern. I argue that the ambivalence and multi-valence of anger expressions and state-sponsored reactions to them render this emotion both subversive vis-à-vis power and subject to manipulations that maintain social order. 相似文献
15.
Ricklefs RE 《The American naturalist》2012,179(4):423-435
Abstract In this essay, I argue that natural history--observing the natural world and deciphering its patterns--is as essential today as it was during Darwin's lifetime to the continuing development of ecology and evolutionary biology. This tradition, which I illustrate through the example of E. O. Wilson's discovery of the taxon cycle 50 years ago, is still very much alive, but there is a growing tendency for observation to serve theory rather provide new insight or to test the predictions of theory. This tendency manifests itself in the failure of ideas about the diversity, distribution, and abundance of species to be informed by patterns in nature that are readily apparent. On the one hand, supporters of neutral theory have sidestepped the unrealistically slow dynamics of random processes in large metacommunities, and they have failed to note global correlations in species numbers and population sizes within taxa. On the other hand, proponents of niche theory have disregarded the implications of variation in distribution and abundance among close relatives, which implies population regulation largely by species-specific agents, such as pathogens. Nor has community niche theory addressed the independence of distribution and abundance with respect to number of close relatives (and presumed competitors). The diversity, abundances, and distributions of species represent the unfolding of many processes over a historically and geographically contingent landscape, for which experimental methods of scientific inquiry are poorly suited. To interpret patterns of diversity, we must continue to depend on inductive reasoning inspired by the data of natural history. 相似文献
16.
Niehrs C 《Differentiation; research in biological diversity》2011,81(4):209-216
A hallmark of embryonic development is the temporal-spatial continuum of cell-cell interactions, which gives rise to the trajectory of progressive cell differentiations. Despite the great reductionists' success in dissecting the mechanistic basis of developmental processes, the call for more holistic system theories never ceased during the last century. Various system theories were proposed to provide a more adequate understanding of biological systems, including development. Although widely ignored by modern biology, the first systematic system theory was Hegel's dialectics. Here I examine the process of embryonic induction as elaborated by Hans Spemann in the light of dialectics. I conclude that embryonic induction and its underlying molecular mechanisms can be re-interpreted in terms of Hegel's dialectics. The example highlights that despite its shortcomings, dialectics can be of heuristic value as a theory of systems biology. 相似文献
17.
《Saudi Journal of Biological Sciences》2017,24(7):1538-1546
The plant cell responds to abiotic stress conditions by adjusting its cellular metabolism and various defensive mechanisms. Cellular metabolism involves changes in the cell cycle, in which the cell undergoes repeated rounds of endocycles leading to polyploidization. Defense mechanisms such as role of antioxidants are a key to understand plant adaptation. The present work describes endoreduplication and radical scavenging activity as two different defense mechanisms adapted by plants for their survival under stress condition. The work describes linkage of these two processes with each other under abiotic stress. Endoreduplicated root tip cells of Allium cepa were depolyploidized by exogenous phytohormones. Further, free radical scavenging activity from normal, endoreduplicated and depolyploidized root tips cells was observed to understand the role of phytohormones. Elevated free radical scavenging potential was observed in endoreduplicated cells compared to normal and depolyploidized cells. Based on these results, it was concluded that endoreduplication and antioxidant pathways are linked with each other through phytohormonal activities. The concentration of auxin and cytokinin regulates the activity of ascorbate oxidase enzyme, which in turn maintains the concentration of AsA within the cell. AsA level directs the prolyl-hydroxylation process of cell division proteins in quiescent center cells either toward endoreduplication process or cell division process. 相似文献
18.
Complementary circular single strands of plasmid PβG or bacteriophage PM2 DNA but not of single-stranded φX174 DNA associate under hybridisation conditions, giving rise to a two-stranded complex. This DNA, which we call form V, has well-defined physico-chemical properties. It sediments as a sharp peak in neutral sucrose gradients; its electrophoretic mobility in agarose gels is between that of covalently closed (form I) and denatured DNA. In the electron microscope form V appears as highly folded duplex molecules indistinguishable from form I. However, increasing concentrations of ethidium bromide which lead to relaxation and recoiling of form I DNA have no comparable effect upon form V. At 260 nm form V PβG DNA has a hypochromicity of 18.6%, as compared to 23.4% in the case of PβG form II DNA and 10.5% in the case of single-stranded φX174 DNA. The thermal melting of form V is non-cooperative with gradual increase in absorbance similar to that of single-stranded DNA. The circular dichroism spectrum of form V DNA differs from that of form I, circular nicked (form II) and single-stranded φX174 DNA in that it shows a negative band at 295 nm and a shift for the main positive band from 273 to 266 nm. We propose that form V consists of right-handed Watson-Crick type double-helices which are compensated by an equal number of left-handed duplex turns and negative supercoils. Wo cannot decide whether left-handed duplex turns are stabilised by base-stacking and hydrogen bonding, as for example in the models described by Rodley et al. (1976) or Sasisekharan &; Pattabiraman (1976), or whether they are merely compensatory turns without inherent stability. 相似文献
19.
Randomly amplified polymorphic DNA (RAPD) loci were used to investigate the origin and genetic relationships of the domesticated sunflower and its wild relatives. A total of 13 primers was employed for the PCR amplifications, from which 68 polymorphic loci were scored. Analysis of RAPD data supports the origin of the domesticated sunflower from wildH. annuus. The high RAPD identity between wild and domesticatedH. annuus (I = 0.976 to I = 0.997) is concordant with a progenitorderivative relationship. However, the identities are very high and therefore provide little information regarding the geographic origin of the domesticated sunflower. Nonetheless, some inferences concerning relationships among domesticated sunflower accessions can be made. The native American varieties and old landracesform a genetically cohesive group based on RAPD evidence, probably due to their origin prior to the use of interspecific hybridization in the development of sunflower cultivars. In contrast, the modern cultivars are not genetically cohesive, perhaps due to the extensive use of intraspecific and interspecific hybridization in the development of modern sunflower varieties. Likewise, little concordance was observed between the geographical origin and genetic clustering of wild populations—an observation probably best explained by the weedy, human dispersed nature of wildH. annuus populations. The information presented here may be a reliable indicator of genetic relationships among wild and domesticated sunflower accessions. However, the processes generating the observed relationships are complex, and the occurrence of unexpected groupings or absence of predicted ones will probably remain difficult to understand. 相似文献
20.
Mitchell F. Balish 《Journal of bacteriology》2014,196(21):3675-3682
In recent decades, bacterial cell biology has seen great advances, and numerous model systems have been developed to study a wide variety of cellular processes, including cell division, motility, assembly of macromolecular structures, and biogenesis of cell polarity. Considerable attention has been given to these model organisms, which include Escherichia coli, Bacillus subtilis, Caulobacter crescentus, and Myxococcus xanthus. Studies of these processes in the pathogenic bacterium Mycoplasma pneumoniae and its close relatives have also been carried out on a smaller scale, but this work is often overlooked, in part due to this organism''s reputation as minimalistic and simple. In this minireview, I discuss recent work on the role of the M. pneumoniae attachment organelle (AO), a structure required for adherence to host cells, in these processes. The AO is constructed from proteins that generally lack homology to those found in other organisms, and this construction occurs in coordination with cell cycle events. The proteins of the M. pneumoniae AO share compositional features with proteins with related roles in model organisms. Once constructed, the AO becomes activated for its role in a form of gliding motility whose underlying mechanism appears to be distinct from that of other gliding bacteria, including Mycoplasma mobile. Together with the FtsZ cytoskeletal protein, motility participates in the cell division process. My intention is to bring this deceptively complex organism into alignment with the better-known model systems. 相似文献