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1.
Lauren Leve 《Dialectical Anthropology》2009,33(3-4):345-363
One of the most frequently advanced explanations of the Maoists’ popularity in rural Nepal links dissatisfaction with the State to forms of consciousness and changes in expectations that are products and processes of development. Such theories often attribute popular support for the insurrection to frustrated desires stemming from “failed” or “incomplete” development. Against this, others suggest that it was the very “success” of empowerment programs which aimed to raise participants’ consciousness of oppression and its roots that inspired villagers to embrace revolutionary action. This paper argues that, despite their differences, both hypotheses reflect assumptions about gendered selfhood and political action that limit their recognition of what motivates Maoist sympathies. Extended research with women in Gorkha—a district where female support for the rebels is said to be especially strong—reveals that Gorkhali women’s support for the rebels is not inspired primarily by the desire for greater autonomy, choice or absolute liberation from social constraints, all of which ideals valorize a culturally specific vision of individual agency. Rather, women there report a sense of self that defines itself through social relations and commitments and which values the common good over individual self-interest, which they associate with an unjust state. The disjuncture between Gorkhali women’s own understandings of self and society and prevailing theories of what motivates people to rebel highlights the modernist assumptions that underlie—and potentially distort—otherwise diverse scholarly perspectives. Likewise, it implies that rebellions may be less about consciousness and more about morality than either “failed” or “successful” theories presume. 相似文献
2.
雄性不育是植物雄性细胞或生殖器官丧失生理机能的现象,该现象的利用大大提高了杂交种生产的效率。植物雄性不育包含细胞质雄性不育、不受环境影响的核雄性不育、光温敏型雄性不育及化学诱导的雄性不育。这些不育类型也已经被以三系或二系的方式应用于很多作物的杂交种生产中。综述了雄性不育各个途径的研究进展及其在作物杂种优势中的应用。 相似文献
3.
We propose a model in which pattern formation is controlled by several concentration gradients of “morphogens” and by allosteric proteins which bind them. In this model, each protein can bind up to two molecules of each morphogen and has an “active state” when one molecule of each morphogen is bound. The concentration of the active state of such a “morphogen binding protein” varies with position in a way that depends on the values given the binding constants. In a contour map of the active state concentration, the contours can have a variety of simple shapes.Simply-shaped regions of cell differentiation can be defined directly by concentration contours of a morphogen binding protein using a threshold-sensing mechanism. More complex shapes may be generated using several proteins and a “winner-take-all” rule according to which each protein specifies some particular sort of cell differentiation and the differentiation of cells in any position is governed by the protein with the highest active state concentration.We present an application of our model to the vertebrate limb skeleton; we use the “winner-take-all” mechanism and thirteen morphogen binding proteins, eleven of which specify cartilage formation. In this model we use one morphogen binding protein to specify the shaft of a typical long bone and one for each epiphysis. Our model is reasonably successful in imitating the in vivo positions and orientations of developing bones and in generating simple, plausible-looking articular surfaces.In addition to the morphogen-binding model we propose a mechanism which could transform morphogen-binding patterns into high-amplitude patterns capable of controlling the activity of structural genes. This “amplifying mechanism” can account for two previously unexplained features of limb skeletal development: the early formation of the diffusely-bounded “scleroblastema” in the limb bud and the center-to-edge gradations in cartilage formation rate which are later seen within individual chondrification foci.A simple modification of the morphogen-binding model provides an explanation for the general anatomical phenomenon of metamerism: The model can account for the formation of inexactly repeating patterns (such as the pattern of the vertebral column) and suggests a mechanism by which such patterns could (1) evolve from exactly repeating patterns, and (2) acquire, in further evolution, a high degree of specialization of the individual repeating units.The most promising approach for testing the morphogen-binding model would appear to involve experiments in which cytoplasm is transferred between cells at various stages of pattern development. Support for the model could also come from the discovery of certain kinds of hereditary limb defects. 相似文献
4.
N. U. Nair 《Biometrical journal. Biometrische Zeitschrift》1983,25(6):557-561
In this article, a simple stochastic model for the time to first conception of a cohort of married women is developed, by identifying three states, ‘adolescent sterile’, ‘ovulating’ and ‘conceived‘, into which they can be placed. It is demonstrated that the model provides a close fit to observed data. The estimates of the parameters in the model, can be used to calculate the number of women in each state at different points of time and also to obtain estimates of the probabilities of conception for the two categories of women, adolescent sterile and biologically mature. 相似文献
5.
Zambian common mole-rats are subterranean rodents that live in families with only one female breeding. Her offspring remain in the parental nest and do not reproduce. Behavioral experiments (Burda, '95) demonstrated that their apparent “sterility” is based on incest avoidance and individual recognition of family members. To elucidate whether some kind of morphologically apparent ovarian suppression still takes place in daughters, ovaries of females of known age, weight, and reproductive histories were examined histologically and morphometrically. The body mass of old females (more than 3 years of age) begins to decrease, and the ovaries seem to begin to atrophy at the age of about 3–6 years. Ovaries in neonates exhibited primordial and primary follicles, sometimes clustered in nests. Ovaries of adult nonbreeding females expressed all stages of the follicular development up to tertiary follicles. Many unruptured luteinized follicles were present, but true corpora lutea as a morphological sign of ovulation were missing. Unruptured luteinized follicles also could be found (additionally to true corpora lutea) in ovaries of breeding females. The number of primordial follicles dropped rapidly during the first 2 years of age; the number of primary, secondary, and tertiary follicles was subject to individual variation; and there was no clear correlation with age or reproductive status. While a tendency to form accessory unruptured luteinized follicles may just reflect taxonomic affinities of bathyergids to hystricomorphs, the otherwise complete folliculogenesis in “sterile” daughters and the presence of unruptured luteinized follicles even in breeding females are further evidence that there is no hormonal suppression of the ovarial cycle. We suggest that ovulation in nonbreeding females is not actively suppressed by the breeding female, but instead that it is not released because the triggering mechanisms, most probably repeated copulation, are missing. J. Morphol. 237:33–41, 1998. © 1998 Wiley-Liss, Inc. 相似文献
6.
Recently, Greenfield has invoked the "Bruce effect' (pregnancy block caused by odors from a strange male) in mice and studies on antisperm antibodies in the serum of prostitutes as support for the hypothesis that promiscuity reduces the fertility of women. This paper disagrees with Greenfield's interpretation and explains why it is invalid to extrapolate such findings in mice to the human condition. Reference is made to studies of human populations that indicate veneral disease may be an important factor in any observed negative correlation between promiscuity and fertility in adults. The phenomenon of adolescent sterility seems likely to be determined mainly by adolescent endocrine imbalance and by immaturity of the female reproductive tract. [population, fertility, promiscuity, sexual relations, adolescent sterility] 相似文献
7.
The scientific approach toward ecological risk assessment (ERA) has advanced greatly during the 1990s. This growth has been accompanied by the development of ERA guidance by USEPA Headquarters, individual USEPA Regions, state environmental agencies, as well as international agencies. This compilation of ERA guidance and procedural documents identifies many of the existing ERA reference materials from the regulatory and/or governmental agency arena. In addition, this compilation provides annotations pertaining to the focus of each reviewed document, and compares/contrasts the approaches presented in the documents. As such, the evaluation provides insight into some of the qualities and levels of detail provided by each document. Examples of documents which are highlighted include recently published USEPA's “Guidelines for Ecological Risk Assessment;” USEPA's “Ecological Risk Assessment Guidance for Superfund;” the U.S. Army's “Procedural Guidelines for Ecological Risk Assessments;” and Environment Canada's “Ecological Risk Assessments Under the Canadian Environmental Protection Act.” 相似文献
8.
9.
Carlos A. Botero Ido Pen Jan Komdeur Franz J. Weissing 《Evolution; international journal of organic evolution》2010,64(11):3123-3133
Communication is a process in which senders provide information via signals and receivers respond accordingly. This process relies on two coevolving conventions: a “sender code” that determines what kind of signal is to be sent given the sender's state; and a “receiver code” that determines the appropriate responses to different signal types. By means of a simple but generic model, we show that polymorphic sender and receiver strategies emerge naturally during the evolution of communication, and that the number of alternative strategies observed at equilibrium depends on the potential for error in signal production. Our model suggests that alternative communication strategies will evolve whenever senders possess imperfect information about their own quality or state, signals are costly, and genetic mechanisms allow for a correlation between sender and receiver behavior. These findings provide an explanation for recent reports of individual differences in communication strategies, and suggest that the amount of individual variation that can be expected in communication systems depends on the type of information being conveyed. Our model also suggests a link between communication and the evolution of animal personalities, which is that individual differences in the production and interpretation of signals can result in consistent differences in behavior. 相似文献
10.
In vitro fertilization has overcome infertility issues for many couples. However, achieving implantation of a viable embryo into the maternal endometrium remains a limiting step in optimizing pregnancy success. The molecular mechanisms which characterize the transient state of endometrial receptivity, critical in enabling embryo‐endometrial interactions, and proteins which underpin adhesion at the implantation interface, are limited in humans despite these temporally regulated processes fundamental to life. Hence, failure of implantation remains the “final frontier” in infertility. A human coculture model is utilized utilizing spheroids of a trophectoderm (trophoblast stem) cell line, derived from pre‐implantation human embryos, and primary human endometrial epithelial cells, to functionally identify “fertile” versus “infertile” endometrial epithelium based on adhesion between these cell types. Quantitative proteomics identified proteins associated with human endometrial epithelial receptivity (“epithelial receptome”) and trophectoderm adhesion (“adhesome”). As validation, key “epithelial receptome” proteins (MAGT‐1/CDA/LGMN/KYNU/PC4) localized to the epithelium of receptive phase (mid‐secretory) endometrium obtained from fertile, normally cycling women but is largely absent from non‐receptive (proliferative) phase tissues. Factors involved in embryo‐epithelium interaction in successive temporal stages of endometrial receptivity and implantation are demonstrated and potential targets for improving fertility are provided, enhancing potential to become pregnant either naturally or in a clinical setting. 相似文献
11.
N. M. Yakovlev K. V. Konstantinov Z. V. Kositskaya V. M. Klimenko 《Human physiology》2007,33(2):163-167
A preliminary study has been performed in order to substantiate the strategy of adaptive self-regulation with external feedback for correction of adolescent deviant behavior. The strategy combines voluntary and involuntary components of correction of the functional state by employing two methods: EEG-controlled switching of an appetent signal (music) (the EEG-controlled biofeedback (EEG-BFB) method) and “tuning” of the patient’s own EEG transformed into an acoustic signal (the EEG bioacoustic correction (EEG-BAC) method). These methods have been demonstrated to be highly effective in normalizing the brain bioelectric activity, psychological state, and behavior of adolescents. It has been demonstrated that it is reasonable to use the EEG-BAC method, which does not impose strict requirements on intelligence, memory, and attention levels, at early stages of treatment, followed by EEG-BFB treatment, which allows the patient to efficiently form a stable skill of transition to a comfortable state. 相似文献
12.
Sandra Wallner-Liebmann Ewa Gralka Leonardo Tenori Manuela Konrad Peter Hofmann Martina Dieber-Rotheneder Paola Turano Claudio Luchinat Kurt Zatloukal 《Genes & nutrition》2015,10(1):1-9
Urine contains a clear individual metabolic signature, although embedded within a large daily variability. Given the potential of metabolomics to monitor disease onset from deviations from the “healthy” metabolic state, we have evaluated the effectiveness of a standardized lifestyle in reducing the “metabolic” noise. Urine was collected from 24 (5 men and 19 women) healthy volunteers over a period of 10 days: phase I, days 1–7 in a real-life situation; phase II, days 8–10 in a standardized diet and day 10 plus exercise program. Data on dietary intake and physical activity have been analyzed by a nation-specific software and monitored by published protocols. Urine samples have been analyzed by 1H NMR followed by multivariate statistics. The individual fingerprint emerged and consolidated with increasing the number of samples and reaches ~100 % cross-validated accuracy for about 40 samples. Diet standardization reduced both the intra-individual and the interindividual variability; the effect was due to a reduction in the dispersion of the concentration values of several metabolites. Under standardized diet, however, the individual phenotype was still clearly visible, indicating that the individual’s signature was a strong feature of the metabolome. Consequently, cohort studies designed to investigate the relation of individual metabolic traits and nutrition require multiple samples from each participant even under highly standardized lifestyle conditions in order to exploit the analytical potential of metabolomics. We have established criteria to facilitate design of urine metabolomic studies aimed at monitoring the effects of drugs, lifestyle, dietary supplements, and for accurate determination of signatures of diseases. 相似文献
13.
Dennis Young 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(3):191-207
In the Second Manifesto of Surrealism, issued by André Breton in 1929, surrealism was described as “a total recuperation of our psychic strength by a means of none other than vertiginous descent into ourselves, systematic illumination of the hidden places and progressive darkening of the other places, a perpetual walk in the forbidden zone”. Surrealism sought to represent the unconscious and forbidden zones of the psyche, of the body, of the noumenal world within, which offered access, for surrealists, to energies and intuitions repressed by “civilized” modes of perception. For Jean Rouch, the significance of surrealism, of automatic writing and ciné‐transe, rested in the potential escape they offered from the formal constraints of conventional film and of conventional perception and observation. In his celebration of ciné‐transe, and of the technological apparatus that makes it possible, it is possible to detect his desire for a freeing‐up of the constraints of consciousness—a desire to “write with the body”, to dream, to tap the unexplored power of the unconscious in its overturning of “reality”, of system, and of convention. As a phaneroscopic “wide‐angle lens”, surreality aimed to document the scientifically unexplainable, the immense experiential overload of ritual possession. It attempted to make visible, in the movement between observation and participation and across disjunctive points of view; the crossings‐over into the unconscious world by which possessed Songhay dancers gained access to powers of phaneroscopic perception. By adopting filmic techniques which follow the surrealist practice of creating “verbal and visual collage”, in which randomly‐generated images, emerging out of a trance‐like state (of “automatic writing” or "ciné‐transe"), are juxtaposed in indeterminate and polyphonic relations with each other in an attempt to disturb or destroy patterns of perception which are confining, rationalistic, linear, or restricted to conscious phenomena, Rouch believed he could create powerful representations of the unknowable. This paper relates the phaneroscopic practice of ethnographic surrealism to psychoanalytic models of the unconscious. In a discussion of Rouch's interpretation of the Hauka spirit cult in his film Les Maîtres Fous, the paper argues that the neo‐Freudian paradigm which allowed him to depict the Sohghay's weekend Hauka rites as a parodic reversion to “savagery” (which both reversed the hierarchy of colonizer/colonized and enabled participants to experience a therapeutic release from the traumas of colonization) has been challenged by Lacanian and post‐Lacanian “re‐readings” of Freud that call into question the extent to which the unconscious can be equated with a pre‐linguistic state characterized by disjunctive “primitive” and “instinctive” energies. The surrealist longing for a rupture of the symbolic order of Western rationalism and a return to the “imaginary order” of the unconscious is confounded in the Lacanian conception of the unconscious as a zone inhabited by the “discourse of the Other”. However, the work of Gillès Deleuze and Félix Guanari [1977] provides a means of conceptualizing the unconscious in terms that avoid simplistic binary logic (phenomenon/noumenon; signifier/signified; subject/object; conscious/unconscious; civilization/savagery). The unconscious is not the “unrepresentable” Other of consciousness; it is a schizophrenic phaneron, a signifying “machine”, a transgressive producer of “group fantasy”. Rejecting both Freud's Oedipal model (the unconscious as primal imagery or “ghostly signifieds"), and the Lacanian notion of the unconscious (as a play of “empty signifiers"). Deleuze and Guattari argue that the unconscious cannot be accounted for in terms of the individual child and its entry into language any more than it can be conceived of as the domain of the primitive. On the contrary, the unconscious is constituted as “group fantasy”, as collective public memory which need not be reduced to elemental (Oedipal) signifiers: “all delirium possesses a world‐historical, political and racial content”. The schizophrenic embodies the public nature of unconscious meaning, since schizophrenia is primarily a communication disorder in which an individual never sees himself in terms of a linguistically‐generated “selfhood”, and fails to adopt the “false” identity which is offered to him in the language of the Other. Schizophrenia is characterized by a refusal to treat some meanings as superior to others, to remain within the bounds of a stable identity, or to distinguish between material (noumenal) things and actions and their (phenomenal) meanings. The schizophrenic unconscious treats all experience as signs, registering language in the same way as the body registers physical stimuli. Thus “meanings in the unconscious are simply meanings as workings of the body” [Harland 1987:174–175]. The schizophrenic as a model for the unconscious holds several implications for those interested in representing the experiential power of public rituals, for the public meanings in circulation during such rituals are material and noumenal, and are registered on the bodies of the dancers as they transgress boundaries and pass beyond consciousness. Rouch's surreality attempted to inscribe this unconscious production of public meaning as it was manifested in the movements of the ritual and in the movements of the camera‐body. 相似文献
14.
The study of the influence of different training regimens on the individual components of the physical state of 7- to 17-year-old school students of different morphofunctional types was carried out. A complex of methods for determining the level of physical development, motor fitness, the muscular capacity for work, the state of the cardiovascular system, and child and adolescent morbidity was used. The study showed the absence of a universal index capable of characterizing the “physical state” on the whole, the measurement of which would make it possible to judge unambiguously the effectiveness of the training process. None of the motor regimens used ensured complete optimization of all the components of the physical state and a decrease in the students’ morbidity. In the course of the experiment, there were many cases in which a training regimen aimed at improving the autonomic regulation of the heart exerted little effect on the total morbidity, a considerable increase in aerobic capacity (as evidenced by the PWC 170 test) was not accompanied by an increased level of overall fitness, etc. It was shown that, to optimize different aspects of the physical state of age-matched students with the same constitutional type, it is necessary to use motor activity regimens that differ in their physiological action. 相似文献
15.
Jessica Blatt 《Ethnic and racial studies》2013,36(5):691-709
The Journal of Race Development [JRD], published out of Clark University in the United States between 1910 and 1919, aimed, in its founder's words, “to present … the important facts which bear upon race progress, and the different theories as to the methods by which developed peoples may most effectively aid the progress of the undeveloped”. Its basic premise was that scientific knowledge could harness racial or civilizational “evolution” and turn it into “development”. This article examines that project, the conceptual apparatus that the JRD's writers and editors brought to bear on it, and how racial ideas informed their conceptions of development and progressive social change through elite scientific and political intervention. Central to this project was an organic notion of “civilization” in which “nature” and “culture” did not so much overlap as flow seamlessly one into the other. 相似文献
16.
Studies on reproductive technologies often examine women’s reproductive lives in terms of choice and control. Drawing on 48 accounts of procreative experiences of religiously devout Jewish women in Israel and the US, we examine their attitudes, understandings and experiences of pregnancy, reproductive technologies and prenatal testing. We suggest that the concept of hishtadlut—”obligatory effort”—works as an explanatory model that organizes Haredi women’s reproductive careers and their negotiations of reproductive technologies. As an elastic category with negotiable and dynamic boundaries, hishtadlut gives ultra-orthodox Jewish women room for effort without the assumption of control; it allows them to exercise discretion in relation to medical issues without framing their efforts in terms of individual choice. Haredi women hold themselves responsible for making their obligatory effort and not for pregnancy outcomes. We suggest that an alternative paradigm to autonomous choice and control emerges from cosmological orders where reproductive duties constitute “obligatory choices.” 相似文献
17.
Bernhard Thomas 《Theoretical population biology》1984,26(1):49-67
Different aspects and modifications of the definition of an evolutionarily stable (ES) strategy that have been considered in the literature can be incorporated in a unifying concept which regards the population context. This concept of evolutionary stability will generally characterize population states in both pure- and mixed-strategist models. In particular, it includes ES strategies, represented as a phenotype unique in an ES population. For an important class of mixed-strategist models, no strict ESS can exist. This will be the case whenever the success of an individual strategy is considered to follow as an average from the successes of its behavioural components. Instead, ESS results may be obtained from what will be called a “degenerate” form of the model, which is simply an ESS model on the level of elementary actions. Then, however, the correct interpretation of an ESS is not an individual phenotype but rather a population mixture of elementary actions. If an ES state exists in a mixed-strategist model it may be determined by an equilibrium condition; if there is an ES strategy, a different approach—mainly maximum considerations—is needed for finding it. An equilibrium condition does not hold for the components of an ES strategy straightforwardly; but it can be derived in terms of an auxiliary ESS model that considers first-order effects of the components. Several examples illustrate the significance of these results. Particularly, two models on “Games between Relatives” are reconsidered in order to display both their formal interrelation and the different meaning of their results in the context of mixed-strategist models. 相似文献
18.
The view according to which damselfly males practice two alternative reproductive tactics of access to females is critically discussed. It is widely accepted that some males (“territorial” ones) have priority as potential female partners, while others (“sneakers” or “wanderers”) are incapable of retaining an individual territory. They have a chance of mating only by intruding briefly into the area defended by a “territorial” male when a female is present there. Thus, the tactics of a “territorial” male consists in waiting for a female in its territory and copulating with it “by agreement,” whereas non-territorial males resort to forced copulations. By observation of individually marked males (48 out of 118) it was shown that every male could be regarded as “territorial” during a certain period and as a “wanderer” before and after it. Thus, no correlation between the modes of space use by a male (residence/mobility) and the characters of its external morphology and/or signal behavior appears to be possible in principle. According to the data obtained, a more plausible explanation is that the female chooses not the male but the best area for oviposition. In addition, it was ascertained that adherence to forced copulations cannot constitute successful “tactics” since they rarely result in insemination, neither by “territorial” nor “non-territorial” males. In other words, we are dealing not with certain alternative tactics (i.e., specialized adaptive mechanisms that have evolved in the species) but simply with the results of different sets of circumstances at a given moment. 相似文献
19.
Summary A general framework is proposed for Bayesian model based designs of Phase I cancer trials, in which a general criterion for coherence (Cheung, 2005, Biometrika 92 , 863–873) of a design is also developed. This framework can incorporate both “individual” and “collective” ethics into the design of the trial. We propose a new design that minimizes a risk function composed of two terms, with one representing the individual risk of the current dose and the other representing the collective risk. The performance of this design, which is measured in terms of the accuracy of the estimated target dose at the end of the trial, the toxicity and overdose rates, and certain loss functions reflecting the individual and collective ethics, is studied and compared with existing Bayesian model based designs and is shown to have better performance than existing designs. 相似文献
20.
A. Sibatani 《Journal of theoretical biology》1978,75(2):149-166
I have constructed, for developmental processes, a qualitative model similar to the compartment hypothesis in Drosophila, and examined its relevance to vertebrate systems. In this model a polarized “cluster” of interacting cells will be the unit for “bifurcation” of the developmental pathway into two alternative states of “locon” which is the genetic unit controlling this process. The minimum size of the cluster critical for bifurcation and the size of the emerging subclusters will be dictated by the cognate locon. This will obviate the need for an extrinsically imposed threshold of some state variable for the boundary of the two subclusters. However, the orientation of bifurcation will be determined by the polarity of the cluster. A physiological factor of competence will impose a temporal constraint to bifurcation.Thus, combinatorial binary codes for a set of locons, like those originally devised by Kauffman (1973), can be assigned to developmental pathways. One of the clusters emerging from a sequence of bifurcations will have the same code as the mother cluster. It will represent the “developmental sink”, and will not recycle through the bifurcation series originating from the initial mother cluster, because of the difference in spatio-temporal factors incorporated in the size and competence of the individual clusters. If bifurcations are prevented, the mother cluster will be forced along the pathway of the developmental sink.I have applied the model to cases in vertebrate development where commitments to developmental pathways for aperiodic or periodic segmentations may follow a linear temporal sequence, producing, in turn, subclusters of uncommitted, or stem, cells towards the more intensely polarized end of the mother cluster. Such cases include limb, somite and tail formation and several stem cell systems with a finite lifespan. I have discussed some possible experimentation which emerges from the model. 相似文献