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1.
This study investigated whether women's interest in visual sexual stimuli varied with their hormonal state. Viewing times of 30 women, 15 normal cycling (NC) and 15 oral contracepting (OC), to sexually explicit photos were measured at three different times. NC women were tested during their menstrual, periovulatory, and luteal phases, and OC women were tested at equivalent temporal intervals. Subjects viewed stimuli as long as desired, thus viewing time measured subject interest. Subjective ratings of stimulus sexual attractiveness were obtained on each test. There was no overall relationship between menstrual cycle phase and viewing time. However the participant's menstrual cycle phase during first exposure to sexual stimuli predicted subsequent interest in sexual stimuli during the next two tests. NC women who first viewed stimuli during their periovulatory phase looked longer at the sexual stimuli across all sessions than did women first tested in their luteal phase. OC women first exposed to the sexual stimuli during menstruation looked longer at the stimuli across all sessions than did OC women first exposed at other test phases. Neither current test phase nor initial cycle phase influenced subjective ratings. Women had increased interest in sexual stimuli across all sessions if first exposed to sexual stimuli when endogenous estrogens were most likely highest. These data suggest that women's interest in visual sexual stimuli is modulated by hormones such that the hormonal condition at first exposure possibly determines the stimuli's emotional valence, markedly affecting subsequent interest in sexual stimuli.  相似文献   

2.
An interest in neurodegenerative diseases drove Junying Yuan to study cell death as a graduate student at Harvard University. Now a full professor at the hallowed institute, Yuan is moved by the same interest in a new direction--the removal of misfolded proteins.  相似文献   

3.
Women experiencing greater childhood adversity exhibit faster reproductive trajectories. One possible psychological mechanism underlying this phenomenon is an increased interest in infants. Interest in infants is thought to be an adaptation important for successful rearing as it motivates the acquisition of caretaking skills. We investigated the relationships between childhood adversity, intended reproductive timing and interest in infants in a sample of English adolescent girls. Specifically we sought to investigate the relationship between 1) childhood adversity and intended reproductive timing; 2) childhood adversity and interest in infants; and 3) intended reproductive timing and interest in infants. Additionally we explored different methods of measuring interest in infants using self-reported fondness for babies, a forced choice adult versus infant paper-based preference task and a novel computer based attention task using adult and infant stimuli. In total 357 girls aged nine to 14 years participated in the study, which took place in schools. Participants completed the two interest in infants tasks before moving on to a childhood adversity questionnaire. Girls with more childhood adversity reported earlier ideal ages at parenthood. We found some evidence that, contrary to our predictions, girls with less childhood adversity were more interested in infants. There was no relationship between intended reproductive timing and interest in infants. The different measurements for interest in infants were only weakly related, if at all, highlighting the complexity of measuring this construct. Our findings suggest that rather than interest in infants being a mechanism for the effect of childhood adversity on early reproductive timing it might instead be an indicator of future reproductive strategies.  相似文献   

4.
John H. Mount  D. G. Fish 《CMAJ》1966,94(14):723-728
The interest of 1900 Canadian medical students in the various fields of medical practice was measured by a questionnaire. The students were asked to rank the various fields in order of their interest in them. It was found that general practice, internal medicine and surgery were the fields which consistently captured most interest among the students. Few students ranked dermatology, administration, teaching and research in the first three ranks.Striking differences in the interest preferences of male and female students were demonstrated, with the women ranking pediatrics and psychiatry higher than the men. Significantly more men, however, expressed a prime interest in surgery.Interest in general practice increases with the senior years in medical school, but it was shown that this increase is associated with marital status and with the number of children rather than with the year of training alone.Interest in the fields of medical practice varied between medical schools, with general practice ranking highest at British Columbia and relatively low at McGill and Manitoba. Significant differences between the students of the schools were displayed in the case of neurology, obstetrics, pediatrics and psychiatry.  相似文献   

5.
This study investigated sex differences in interest in infants among children, adolescents, young adults, and older individuals. Interest in infants was assessed with responses to images depicting animal and human infants versus adults, and with verbal responses to questionnaires. Clear sex differences, irrespective of age, emerged in all visual and verbal tests, with females being more interested in infants than males. Male interest in infants remained fairly stable across the four age groups, whereas female interest in infants was highest in childhood and adolescence and declined thereafter, particularly for the responses to visual stimuli. The observed developmental changes in female interest in infants are consistent with the hypothesis that they represent a biological adaptation for parenting. This study was supported by NIH grants R01-MH57249, R01-MH62577, and K02-MH63097. Dario Maestripieri, Ph.D., is an assistant professor of Human Development and Evolutionary Biology at the University of Chicago. He has broad research interests in behavior, development, and evolution, and conducted research on primate parenting and development at the University of Cambridge and at the Yerkes Regional Primate Research Center before moving to Chicago. Suzanne Pelka is a graduate student in Human Development at the University of Chicago.  相似文献   

6.
Increasing biomedical workforce diversity remains a persistent challenge. Recent reports have shown that biomedical sciences (BMS) graduate students become less interested in faculty careers as training progresses; however, it is unclear whether or how the career preferences of women and underrepresented minority (URM) scientists change in manners distinct from their better-represented peers. We report results from a survey of 1500 recent American BMS Ph.D. graduates (including 276 URMs) that examined career preferences over the course of their graduate training experiences. On average, scientists from all social backgrounds showed significantly decreased interest in faculty careers at research universities, and significantly increased interest in non-research careers at Ph.D. completion relative to entry. However, group differences emerged in overall levels of interest (at Ph.D. entry and completion), and the magnitude of change in interest in these careers. Multiple logistic regression showed that when controlling for career pathway interest at Ph.D. entry, first-author publication rate, faculty support, research self-efficacy, and graduate training experiences, differences in career pathway interest between social identity groups persisted. All groups were less likely than men from well-represented (WR) racial/ethnic backgrounds to report high interest in faculty careers at research-intensive universities (URM men: OR 0.60, 95% CI: 0.36–0.98, p = 0.04; WR women: OR: 0.64, 95% CI: 0.47–0.89, p = 0.008; URM women: OR: 0.46, 95% CI: 0.30–0.71, p<0.001), and URM women were more likely than all other groups to report high interest in non-research careers (OR: 1.93, 95% CI: 1.28–2.90, p = 0.002). The persistence of disparities in the career interests of Ph.D. recipients suggests that a supply-side (or “pipeline”) framing of biomedical workforce diversity challenges may limit the effectiveness of efforts to attract and retain the best and most diverse workforce. We propose incorporation of an ecological perspective of career development when considering strategies to enhance the biomedical workforce and professoriate through diversity.  相似文献   

7.
Minimization of the variance of the difference between estimated responses at two points maximized over pairs of points in the region of interest is taken as the design criterion. Optimal third-order designs are derived for spherical co-centric regions of experimentation and interest with some restrictions imposed on the pairs of points under consideration.  相似文献   

8.
Efforts to meet the welfare needs of captive animals (such as the provision of environmental enrichment and naturalistic furnishings) often compromise visitors’ needs (naturalistic exhibits often decrease the visibility of animals on display even though visitors pay to view them). The literature offers different predictions about how zoo visitors respond to decreased animal visibility in naturalistic exhibits but they require further evaluation. Further, visitor research is currently confined to Europe and America and studies outside these areas are limited. This paper investigates the relationships between exhibit naturalism, animal visibility and visitor interest in a Chinese Zoo. Visitor interest was observed at both naturalistic and barren exhibit designs. The study showed that the influence of animal presence on visitor behaviours was similar at both exhibit designs. Further, visitor interest was not compromised at the naturalistic exhibit when animals were not visible. The results demonstrate that the needs of animals and visitors can be balanced at naturalistic exhibits and support the transformation of exhibits to those representing naturalistic environments.  相似文献   

9.
Adam Smith proposed that individuals can share sufficient interest in their society's welfare to profit by cooperating for its benefit and by jointly suppressing behavior hurtful to it. Similarly, a genome's genes share a common interest in 'honest' meiosis, which ensures that alleles can spread only by benefitting their carriers. Honeybee workers express a common interest in raising their queen's, rather than their half-sisters', eggs by eating eggs laid by half sisters. Can analogous principles explain the evolution of harmony at other levels of biological organization, such as ecosystems or organismic development?  相似文献   

10.
We have developed an inducible system for high level expression of heterologous genes in murine hybridoma cells. The rapid induction by methotrexate (MTX) does not involve gene amplification and is controlled at the level of mRNA accumulation. Transfection was achieved by protoplast fusion with an expression vector containing the cDNA of interest and a marker gene encoding dihydrofolate reductase. The initial clones, selected at 100 nM MTX, produced high levels of the protein of interest and contained about 100-400 copies of the integrated plasmid DNA. They could adapt to a 100- to 1000-fold stepwise increase in MTX concentration in a few weeks, during which the expression of the gene of interest but not its copy number, increased several-fold. Furthermore, the induction is freely reversible. If cells were propagated in MTX-free media, the expression level decreased, but the cells could be reinduced to their original high level of expression by adding MTX back to the media. A several-fold increase in the mRNA levels of the dihydrofolate reductase and the gene of interest could be detected after induction for 18 h.  相似文献   

11.
The extent to which the presence of zoo visitors influences animal behavior, and the ways in which animal activity influences visitor interest and perception, are of great interest to zoological parks. Visitors have been variously characterized as being enriching for zoo animals, as being stressors, and generally as influencing behavior in measurable ways. Most studies have focused on primates, and have assumed a “visitor effect” paradigm (i.e., visitors influence animal behavior). Here we present findings from a study of a nonprimate group (felids), and examine the “visitor attraction” model, which assumes that visitors are attracted to active animals. We assessed visitor interest and number at seven cat exhibits at the Brookfield Zoo during the spring and summer of 2002. Data were collected during 1‐min scans of each exhibit at 10‐min intervals. The results indicate that visitor presence per se did not influence cat activity, and that visitor interest was generally greater when cats were active. Various species differences may be explained by visitor familiarity with the species, variations in exhibit design, and species‐specific activity budgets. We conclude that the visitor attraction model may be more appropriate for taxa, such as large cats, that tend naturally to be largely inactive and to respond little (if at all) to visitor disturbances or efforts to engage. The relationship must be viewed as bidirectional: visitors influence animal behavior, and animal behavior influences visitor interest. However, the strength and primary direction of this relationship is likely taxon‐specific. We suggest that a visitor attraction model may be more appropriate not only for felids, but for other taxa with similar behavioral patterns and responses as well. Zoo Biol 22:587–599, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   

12.
The ability to generate isogenic sets of strains with mutations in a gene of interest but not in other genes by repeated use of the URA3 marker (Ura-blaster methodology) has advanced our understanding of the relationships between gene structure and function in Candida albicans. Common applications of Ura-blaster technology result in different genomic positions for the URA3 gene in strains complemented for the gene of interest compared with mutant strains. Studies using animal models of systemic candidiasis pointed to possible differences in URA3 gene expression, depending on its genomic location, which confounded interpretation of the role of the gene of interest in lethality. Positional effects on URA3 expression can be avoided by placement at a common locus in all strains used for comparison.  相似文献   

13.
14.
《Endocrine practice》2011,17(3):356-362
ObjectiveTo examine whether establishment of a pheochromocytoma interest group improves diagnosis and management of pheochromocytoma in an academic hospital.MethodsThe medical records of patients who had preoperative or pathologic diagnosis of pheochromocytoma at a large academic hospital from July 2007 to July 2010 were retrieved and pertinent information was gathered. Quality measures for diagnosis and management of pheochromocytoma before and after establishment of a pheochromocytoma interest group, and by group and nongroup physicians, were compared.ResultsBetween 2007 and 2010, 16 patients were confirmed to harbor pheochromocytoma. The rates of overdiagnosis and underdiagnosis were similar before and after establishment of the pheochromocytoma interest group (23%-25% vs 17%, respectively); however, after interest group formation, pheochromocytoma was excluded in 9 patients for whom other physicians recommended adrenalectomy. Compared with nonmembers, members of the pheochromocytoma interest group more frequently performed pheochromocytoma testing before adrenal biopsy or adrenalectomy in patients with adrenal masses (71% vs 13%), including those with suspected malignancy (50% vs 7%). After interest group formation, many more patients were optimally prepared preoperatively and advised on follow-up plan and genetic testing.ConclusionsFormation of a pheochromocytoma interest group significantly enhances the quality of diagnosis and management of pheochromocytoma. The key to the group’s success is its incorporation of members’ formal or informal opinions into the care of patients with suspected pheochromocytoma. This model may be applied to other rare endocrine diseases. (Endocr Pract. 2011;17:356-362)  相似文献   

15.
Kang SH  Shin D 《Human heredity》2004,58(1):10-17
Many scientific problems can be formulated in terms of a statistical model indexed by parameters, only some of which are of scientific interest and the other parameters, called nuisance parameters, are not of interest in themselves. For testing the Hardy-Weinberg law, a relation among genotype and allele probabilities is of interest and allele probabilities are of no interest and now nuisance parameters. In this paper we investigate how the size (the maximum of the type I error rate over the nuisance parameter space) of the chi-square test for the Hardy-Weinberg law is affected by the nuisance parameters. Whether the size is well controlled or not under the nominal level has been frequently investigated as basic components of statistical tests. The size represents the type I error rate at the worst case. We prove that the size is always greater than the nominal level as the sample size increases. Extensive computations show that the size of the chi-squared test (worst type I error rate over the nuisance parameter space) deviates more upwardly from the nominal level as the sample size gets larger. The value at which the maximum of the type I error rate was found moves closer to the edges of the the nuisance parameter space with increasing sample size. An exact test is recommended as an alternative when the type I error is inflated.  相似文献   

16.
The need to develop new concepts in reactor design and the growing interest inSpirulina prompted our group to abandon open ponds in the seventies and to focus interest mainly on closed systems. Two substantially different closed photobioreactors have been developed and are at present under investigation in our Research Centre: the tubular photobioreactor (made of rigid or collapsible tubes) and the recently devised vertical alveolar panel (VAP) made of 1.6-cm-thick Plexiglas alveolar sheets.The technical characteristics of the two systems are described and discussed in relation to the main factors which regulate the growth of oxygenic photosynthetic microorganisms in closed reactors.This paper was presented at the Symposium on Applied Phycology at the Fourth International Phycological Congress, Duke University.  相似文献   

17.
Each cell in a multicellular organism permanently adjusts the concentration of its cell surface proteins. In particular, epithelial cells tightly control the number of carriers, transporters and cell adhesion proteins at their plasma membrane. However, sensitively measuring the cell surface concentration of a particular protein of interest in live cells and in real time represents a considerable challenge. Here, we introduce a novel approach based on split luciferases, which uses one luciferase fragment as a tag on the protein of interest and the second fragment as a supplement to the extracellular medium. Once the protein of interest arrives at the cell surface, the luciferase fragments complement and generate luminescence. We compared the performance of split Gaussia luciferase and split Nanoluciferase by using a system to synchronize biosynthetic trafficking with conditional aggregation domains. The best results were achieved with split Nanoluciferase, for which luminescence increased more than 6000-fold upon recombination. Furthermore, we showed that our approach can separately detect and quantify the arrival of membrane proteins at the apical and basolateral plasma membrane in single polarized epithelial cells by detecting the luminescence signals with a microscope, thus opening novel avenues for characterizing the variations in trafficking in individual epithelial cells.  相似文献   

18.
Identification of in vitro and in vivo released mycobacterial antigens are of considerable interest in diagnosis of Mycobacterium tuberculosis. Isolation of in vitro released antigen from M. tb excretory-secretory culture filtrate protein and in vivo released circulating tuberculous antigen from smear positive pulmonary tuberculosis sera by ammonium sulphate precipitation is reported. The antigens were resolved by SDS-PAGE and immunoblotting was performed using pooled serum of smear positive, smear negative pulmonary tuberculosis sera and normal sera to identify reactive tuberculous antigens. In vitro and in vivo released mycobacterial antigens showed reactivity at 100, 31, 43 and 20 kDa with smear positive and smear negative pulmonary tuberculosis patients. Further, the in vitro released antigen showed strong reactivity exclusively at 55 kDa antigen with smear positive and 24 kDa antigen with smear negative pulmonary tuberculosis sera. In vivo released antigen reacted exclusively at 170 and 16 kDa with smear positive and 19 kDa antigen with smear negative pulmonary tuberculosis patients. Antigens of 24 and 19 kDa which are reactive with sputum negative sera will be of diagnostic interest and need further study in patients with low bacillary load. The in vitro and in vivo released mycobacterial 100, 31,43 and 20 kDa antigens, reactive with patients sera are of diagnostic interest in tuberculosis.  相似文献   

19.
Environmental enrichment is thought likely to benefit chickens and farmers in many ways; these include reduced fearfulness and feather pecking and improved productivity. Enrichment devices would intuitively be more effective if they reliably attracted and sustained appreciable interest but many fail to do so. This may reflect the fact that the choice of stimuli often reflects availability and human preconceptions rather than a critical consideration of the birds' preferences and pre-dispositions. We had previously identified string as a particularly attractive pecking stimulus for chicks and adult hens (Gallus gallus domesticus) of a laying strain (ISA Brown). In the present study we found that chicks of another laying strain (Lohmann Brown) also pecked sooner and more at a bunch of string than at chains or beads (Experiment 1). White or yellow strings were preferred to red, green or blue ones (Experiment 2) and white string elicited more pecking than did combinations of white and yellow or of all five colours (Experiment 3). Varying the length and width of the bunches of string exerted no detectable effects on pecking (Experiment 4) whereas incorporating small, shiny beads in the white string devices actually reduced pecking (Experiment 5). Virtually all the devices elicited progressively more interest with repeated presentation; this trend was particularly marked for white string. Collectively, the present findings demonstrate that young domestic chicks have clear and specific pecking preferences. Although the magnitude of response varied across experiments, white string consistently elicited the most interest. Our two main conclusions are: (i) white or yellow strings were particularly attractive stimuli that drew increasing interest, at least in the short term, and (ii) simple devices were preferred to more complex ones, or at least to those used here.  相似文献   

20.
Femke Takes 《Bioethics》2022,36(1):10-17
Procreation with donor gametes is widespread and commonly accepted, but it involves ethical questions about the child's best interest. Understanding the historical structures of the moral discussion of gamete donation may contribute to reflecting on the child's best interest. This is why I have analysed the debate on gamete donation in the Netherlands, and this analysis has uncovered some striking discontinuities. Notions of the child's best interest have undergone a radical swing. In the past, it was considered acceptable to conceal the truth about the child's biological origin, but in the past two decades the general opinion has changed to the common belief that this information should be shared with the child. This changed notion of the child's best interest will be analysed using a framework encompassing three views of the child, which derive from the debate on children's rights. These three views each provide a different interpretation of the child's moral and political status. I conclude that the changed notion of the child's best interest results from a view of the child that focuses on autonomy and citizenship, and which frames the child's interests according to its legal status. I comment on this view and I champion an alternative one, namely ‘the embedded child’. This is a relational view based on care ethics that goes beyond what can be articulated in law, and that will help to establish a more balanced interpretation of the child's best interest at the practice and policy levels of gamete donation.  相似文献   

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