1000 resultados para Boston Female Asylum.


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Female choice is an important element of sexual selection that may vary among females of the same species. Few researchers have investigated the causes of variation in selectivity with respect to potential mates and overall level of motivation toward a stimulus source representative of a mate. This study demonstrates that female age may be one cause of variation in female choice. Females of different ages may have different mate preferences. As females age, they have less time left to reproduce, and their residual reproductive value decreases. This should correspond to a higher reproductive effort which may be represented as increased motivation and/or decreased selectivity. The effect of age on mate choice in Gryllus integer was investigated by using a non-compensating treadmill, called the Kugel, to measure female phonotaxis. Artificially generated male calling songs of varying pulse rates were broadcast in either a singlestimulus or a three-stimulus experimental design. The pulse rates used in the calling song stimuli were 70, 64, 76, 55 and 85 pulses per second. These corresponded to the documented mean pulse rate for the species at the experimental temperature, one standard deviation below and above the mean, and 2.5 standard deviations below and above the mean, respectively. Test females were either 11-14 days or 25-28 days post-ecdysis. Trials usually were conducted two to seven hours into the scotophase. In the single-stimulus experiment, females were presented with stimuli with only one pulse rate. Older females achieved higher vector scores than younger females, indicating that older females are more motivated to mate. Both groups showed little phonotactic response towards 55 or 85 pIs, both of which lie outside the natural range of G. integer calling song at the experimental temperature. Neither group discriminated among the three pulse rates that fell within the natural range of calling song. In the three-stimulus experiment, females were presented with stimuli with one of three pulse rates, 64, 70 or 76 pIs, In alternation. Both age groups had reduced responsiveness in this experiment, perhaps due to an increase in perceived male density. Additionally, younger females responded significantly more to 64 and 70 pIs than to the higher pulse rate, indicating that they are selective with respect to mate choice. Older females did not discriminate among the three pulse rates. Therefore, it was concluded that selectivity decreases with age. A further study was conducted to determine that these effects were due to age and not due to the differing periods without a mating between the two age groups. Again, stimuli were presented in a three-stimulus experimental design. Age was held constant at 28 days and time since last mating varied from 11 to 25 days. Females varyIng in time since last mating did not differ in their responses to the calling song pulse rates. This indicated that the increased motivation and decreased selectivity exhibited In the initial experiments were due to age and not to time without a mating. Neither time of trial nor female weight had an effect upon female phonotaxis. Data are discussed in terms of mate choice, residual reproductive value, and costs of choice.

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The heritability of multiple mating in female Gryllus integer crickets was studied. Two preliminary experiments were conducted to determine when females first mate following the post-imaginal moult and to ascertain whether constant exposure to males affects female mating rate. Female Q. integer first mated at an average age of 3.6 days (S.D. = 2.3, Range = 0-8 days) . Exposing female crickets to courting males 24 hr daily did not significantly alter mating rates from those females in contact with males for only 5 hr per day. A heritability value of 0.690 ± 0.283 was calculated for multiple mating behavior in female Q. integer using a parent-offspring regression approach. Parental females mated between land 30 times (x 9.8, S . D. = 6. 6 ) and offspring matings ranged from 0 to 26 times (x 7 .3, S.D. = 3.4). Multiple mating is probably a sexually selected trait which functions as a mechanism of female choice and increases reproductive success through increased offspring production. Classical theory suggests that traits intimately related with fitness should exhibit negligible heritable variation. However, this study has shown that multiple mating, a trait closely linked with reproductive fitness, exhibits substantial heritability. These results are in concordance with a growing body of empirical evidence suggesting many fitness traits in natural populations demonstrate heritabilities far removed from zero. Various mechanisms which may maintain heritable variation for female multiple mating in wild, outbred Q. integer populations are discussed.

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The objective of this investigation was to clarify the adaptive significance of female sexual behaviours in the house cricket, Acheta domesticus, and the Texas field cricket, Gryllus integer. Experiments were focussed primarily on: nutritional factors affecting female reproductive success; the ontogeny of female sexual behaviours; female mating frequency and progeny production; and the pattern of sperm competition. Reproduction of singly mated female A. domesticus assigned to 3 nutritional regimes was compared . Females fed a vitamin and protein-enriched mouse chow, cannibalistic females, and starved females produced on the average, 513 , 200 and 68 offspring, respectively. Cannibals probably could not obtain the same amounts of essential nutrients as females fed mouse chow. Reabsorption of oocytes was likely the major factor contributing to the decreased reproduction of starved females. In addition, female !. domesticus fed mouse chow, but allowed constant access to males produced 11 times as many offspring than did females fed corn meal. Females fed corn meal probably could not absorb or synthesize enough dietary lipids, thus resulting in poor ovariole growth. Female !. domesticus first mate at an average adult age of 7 days, closely corresponding to when they first exhibit positive phonotaxis. Females mate repeatedly and often consume the externally attached spermatophore. In ~. domesticus, females allowed constant access to males produced significantly more offspring than did single maters. Similarly, doubly mated G. integer females produced more offspring than did single maters. This difference resulted largely from the failure of many single maters to reproduce. Remating by female crickets partly functions in offsetting the possibility of a failed initial mating. Nymph production increased significantly with the time the spermatophore was attached in singly mated ~. domesticus. Spermatophore consumption by the female was not affected by male guarding behaviour, and the interval between mating and eating of the spermatophore may often be shorter than the time required for maximum insemination. Some degree of sperm depletion in singly mated !. domesticus and G. integer may have occurred. The patterns of daily offspring production of singly and multiplymated females suggests that a factor provided by a male during mating stimulates female oviposition and/or egg production. Female crickets also might acquire nutrition from spermatophore consumption, a benefit that is augmented by female multiple mating. The electrophoretic examination of various allozymes in ~. integer did not permit determination of a pattern of sperm competition. However, the possibility of last male sperm predominance is related to male guarding behaviour.

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Female crickets respond selectively to variations in species-specific male calling songs. This selectivity has been shown to be age-dependent; older females are less choosy. However, female quality should also affect female selectivity. The effect of female quality on mate choice was examined in Gryllus integer by comparing the phonotactic responses of females on different diets and with different parasite loads to various synthetic models of conspecific calling song. Test females were virgin, 11-14 days old, and had been maintained on one of five diets varying in protein and fat content. Phonotaxis was quantified using a non-compensating Kugel treadmill which generates vector scores incorporating the speed and direction of movement of each female. Test females were presented with four calling song models which differed in pulse rate, but were still within the natural range of the species for the experimental temperature. After testing, females were dissected and the number of gregarine parasites within the digestive tract counted. There were no significant effects of either diet or parasitism on female motivation to mate although the combined effects of these variables seem to have an effect with no apparent trend. Control females did not discriminate among song types, but there was a trend of female preferences for lower pulse rates which are closest to the mean pulse rate for the species. Heavily parasitized females did not discriminate among pulse rates altho~gh there was a similar trend of high vector scores for low pulse rates. Diet, however, affected selectivity with poorly-fed females showing significantly high vector scores for pulse rates near the species mean. Such findings raise interesting questions about energy allocation and costs and risks of phonotaxis and mate choice in acoustic Orthoptera. These results are discussed in terms of sexual selection and female mate choice.

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Research interest on the topic of female coaches as role models has recently emerged in the coaching literature. Social learning theory (Bandura, 1963; 1977; 1986) has also emerged as an essential framework in explaining learning through modeling. Previous research has examined the coach as a role model, as well as gender differences between coaches. Several authors, with several different conclusions, have studied the significance of gender as an influencer in role modeling. Whitaker and Molstad in 1988 conducted a study focusing on the coach as a role model. What they found was when they combined the results of high school and college aged athletes; the female coach was considered to be a superior role model. The current research used a social learning theory framework to examine the benefits and intricacies of the modeling relationship between female adolescent athletes and influential female coaches. To accomplish this task, the formative experiences of thirteen adolescent female athletes were examined. Each athlete was interviewed, with each semi-structured interview focusing on extracting the salient features of a coach that the athlete identified as being the most influential in her personal development. The data from these interviews were quaHtatively analyzed using case studies. From case studies, a template emerges in which the coach/athlete relationship can be seen as an essential construct in which caring and strong role models can have lasting effects on the lives, values, and successes of adolescent female athletes.

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The purpose ofthis study was to explore the perceptions of wellness and bidance amongst female health care professionals negotiating career, family aiul continuing education commitments. Five women who met the criteria of having a family (with children), holding a full-time professional career in health care, and who were presently pursuing continuing education were interviewed. This paper begins with the introduction to the topic of research and the questions to be answered. The review of literature explores the theory and research A^ch precede this study and addresses the surrounding areas of: wellness, balance, multiple roles, stress and continuing education. < This study has assumed a qualitative, phenomenological approach. The data collected through the use of individual interviews were analyzed using a two-part process. Analysis using both (a) methodological interpretation and (b) The Listening Guide method has allowed for the uncovering of major themes, and the portrayal of each participant's unique experience. Some of the major themes which emerged from this research include: wellness as multidimensional and fluctuating, making personal sacrifices, the presence of stress, professional as a vital role, and continuing education as something for me. Perhaps the most significant finding this research has identified is the positive role continuing education can hold in the lives of women already negotiating multiple commitments. The notion that continuing education can act as a means of enhancing perceptions of wellness and balance holds a number of implications in theory, practice, and for future research.

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This thesis explores the impact of recent social welfare reforms on the lives of social assistance recipients. The focus is on single mothers who are dependent on social assistance in a small city in southern Ontario. This detailed examination is complemented with existing case studies in Canada, the United States and New Zealand, as well as aggregate data on poverty in Canada. Participants for the research study were recruited by flyer distribution and referral. Following recruitment, selected participants were scheduled for a tape- recorded interview. The final sample population consists of eight single mothers on social assistance and/or workfare participants. This information is supplemented with interviews from two Ontario Works caseworkers and two Women's Advocates from a local crisis housing organization. This research project is guided by a socialist feminist framework. Evidence from interview participants suggest that single mothers continue to struggle in terms of meeting basic needs, such as food, clothing and medications. Housing for low-income families is a concern expressed by the participants as well as by Women's Advocates who operate within the region. In addition, subsidized housing continues to be problematic in terms of both safety and availability. Recent social welfare refonns (reductions in welfare income and introduction of workfare features) have intensified the economic and social marginalization of these women. Participants, for example, voice concerns about valuing self-evaluation in their Ontario Works and workfare activities. Considerable evidence from interview participants suggest that single mothers remain economically marginalized.

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Objectives: The primary objective ofthis study was to explore motivation and psychological need salience in the initiatory and maintenance experiences of older female exercIsers. Methods: Female initiates (n = 3) and reflective maintainers (n = 3) 65 years of age or older (M = 76 years; SD = 5.37) participated in semi-structured interviews. Data were analyzed holistically and categorically, following a hermeneutic approach to inquiry. Results: Perceived importance of exercise benefits appeared to be the strongest motive for initiates at this stage of life and connections to others were perceived as valued, but less important in exercise contexts. Also, listening to one's body over instructions from the exercise leader emerged as a key factor to success. Conclusions: Overall, the results ofthis study implicate more self-determined than controlled motives as sources of regulation in older females' exercise initiation experiences. Evidence for psychological needs was more heterogeneous and less conclusive.

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The purpose of the study was two-fold; first, the association between interpersonal coaching styles and self-determined motivation was examined, followed by the investigation of the motivation-performance relationship. Participants included 221 female Canadian Interuniversity Sport (CIS) rugby players, aged sixteen to thirty-three (M= 20.1: SD = 2.26), who reported the number of years they played CIS rugby (M= 2.3: SD = 1.37) and organized rugby (M= 5.9: SD = 2.31). Multiple and bivariate regressions were employed with autonomy-support, structure, and involvement accounting for 17%, 41 % and 22% of the variance of competence, autonomy and relatedness. The three basic needs accounted for 40% of the variance of motivation, and motivation accounted for 2% of the variance of athletes' perceptions of performance. Findings indicated that autonomy-support emerged as a predictor of all three basic needs, involvement predicted relatedness and competence, autonomy predicted motivation, and motivation predicted athletes' perception of performance.