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1.
Trivers and Willard's theory of sex-ratio adjustment, as applied to cercopithecines, predicts that the ratio of male to female offspring will be greater for dominant than for subordinate mothers. A local-resourcexyhcompetition hypothesis predicts the reverse. To date, results from several species of macaque are inconsistent and often not statistically significant. In this 21 year study, a colony group of stumptailed macaques is added to the species previously studied. Seventy-five offspring were born to eight mothers for whom long-term dominance was established. Chi-square analyses of data from these 75 offspring failed to yield a significant relationship between sex-ratio and mother's dominance; consequently, consistent with a growing body of cercopithecine literature, neither of the competing theories was supported. © 1994 Wiley-Liss, Inc.  相似文献   

2.
Apterous exules of Rhopalosiphum padi which experienced short photoperiods only during the first half of their nymphal life all produced gynoparae which made up 57% of the offspring produced in the first 7 days of the mother's reproductive life. Short photoperiods during the second half of a mother's nymphal life did not induce the production of gynoparae. However, when short photoperiods were experienced throughout a mother's nymphal life significantly more gynoparae (82%) were produced. Ten per cent of the offspring of mothers that experienced short photoperiods only during their adult life developed into gynoparae. Of the offspring reared in short photoperiods, but born to mothers reared and kept in long photoperiods, 30% developed into gynoparae. When mothers were exposed to short photoperiods in their adult life and their offspring so treated, then 90% of the offspring developed into gynoparae. Males only occurred amongst the last offspring of mothers that experienced short photoperiods in either the first or the second half of their nymphal life.  相似文献   

3.
Objective: To evaluate the accuracy of mothers’ perceptions of adolescents’ weight status. Research Methods and Procedures: Parent interviews and adolescent surveys (755) were conducted in an ethnically diverse sample from Project EAT (Eating among Teens). Results: Adolescent weight status was accurately assessed by 60% of mothers, underestimated by 35% of mothers, and overestimated by 5% of mothers. In multivariate analyses, mothers of female adolescents were about half as likely to underestimate their adolescent's weight status as mothers of male adolescents. Nonoverweight mothers were about half as likely as overweight mothers to underestimate their adolescent's weight status. Discussion: Most mothers are able to accurately assess their adolescent's weight status; however, adolescent gender and mothers’ weight status are related to accuracy. Mothers were more likely to underestimate their sons’ weights than their daughters’ weights, and overweight mothers were more likely to be inaccurate in their assessments than nonoverweight mothers. Findings suggest that the majority of parents do not need to be told that their children are overweight; instead, messages to parents of overweight teens should focus on how to provide support for healthy weight management.  相似文献   

4.
The kidneys of nine fetuses whose mothers were chronically hypertensive were examined microscopically. Three of these mothers used antihypertensive agents throughout pregnancy including one who used an angiotensin-converting enzyme (ACE) inhibitor. The tubular defects found in these kidneys were compared to the kidneys of 20 normal controls, 13 fetuses with various multiple malformation syndromes and six cases of the twin to twin transfusion syndrome. Evidence from these cases as well as the literature suggest that the primary mechanism by which ACE inhibitors affect development of the fetal kidney is through decreased renal blood flow.  相似文献   

5.
Activities of serum long acting thyroid stimulator protector were measured in a series of nine pregnancies in eight mothers who had Graves'' disease, one of whom had been successfully treated by surgery. In all but two instances the activities tended to decline as pregnancy progressed. After delivery activities rose in three out of five patients in whom these had disappeared in pregnancy and, as this occurred, the patients relapsed. In the two patients whose activities did not decline thyrotoxicosis persisted throughout pregnancy and after delivery. None of the nine babies in this study suffered from neonatal thyrotoxicosis because maternal activities of the thyroid stimulator protector, though high enough to induce Graves'' disease in adults, were not above the threshold for the induction of thyroid overactivity in neonates.  相似文献   

6.
OBJECTIVE--To determine the sociodemographic and motivational characteristics of parents who volunteer their children for clinical research. DESIGN--A questionnaire was administered to parents who volunteered their children for a randomised, double blind, placebo controlled trial of a drug to treat asthma and to a control group of parents whose children were eligible for the trial but had refused the invitation. SETTING--A children''s hospital in Australia. SUBJECTS--68 Parents who had volunteered their children and 42 who had not; a response rate of 94% and 70%, respectively. MAIN OUTCOME MEASURES--Responses of parents to questionnaire designed to assess their perceptions, attitudes, and health seeking behaviour as well as sociodemographic data. RESULTS--Volunteering parents were less well educated with only 15% (10/68) of mothers and 16% (11/68) and of fathers having had a tertiary or university education compared with 26% (11/42) of mothers and 45% (19/42) in the non-volunteering group. Fewer volunteering parents had professional or administrative jobs than did non-volunteering parents (mothers 6% (4/68); fathers 9% (6/68) v mothers 14% (6/42); fathers 31% (13/42)). Volunteering parents had less social support, and they displayed greater health seeking behaviour and consumed more habit forming substances. They were motivated by a desire to help others and to contribute to medical research, but they were also searching for more information and better ways to help their own children. CONCLUSION--Parents who volunteer their children for medical research are significantly more socially disadvantaged and emotionally vulnerable.  相似文献   

7.

Background

Assisting mothers to breastfeed is not easy when babies experience difficulties. In a neonatal intensive care unit (NICU), nurses often help mothers by using hands-on-breast without their permission. Little is known about how mothers feel about this unusual body touching. To gain more knowledge from mothers who lived through this experience, this hands-on practice was studied in a NICU in Sweden.

Methods

Between January and June 2001, in-depth interviews were conducted with ten mothers of preterm or sick term infants and all of them experienced the hands-on approach. In this research, Radnitzky's seven principles of hermeneutic interpretation were applied in order to interpret the meaning of mothers' responses. This article presents results related to the period of initiation of breastfeeding. This qualitative study was based on a combination of the models of Gustafsson, Orem, and Aarts' Marte Meo.

Results

Five main themes were identified: Insult to integrity, Manipulating the baby, Understanding and adjustment, Breasts as objects, Alternatives to this practice. Hands-on help in the breastfeeding situation was experienced as unpleasant and the women experienced their breasts as objectified. The mothers accepted the hands-on help given by nursing staff, even though they considered it unpleasant. Most mothers expressed a need for assistance when starting breastfeeding, but could not suggest any alternative to hands-on help such as demonstrating with an artificial breast and a doll.

Conclusion

The study provides information about how mothers experience unexpected hands-on help with breastfeeding in a NICU, which has not been described previously. Since most mothers in this study regarded this behavior as unpleasant and not helpful mostly because it was unexpected and unexplained, it would be important to either explain beforehand to mothers what type of physical approach could be attempted on their body or better, to avoid this type of approach completely.  相似文献   

8.

Introduction

Mothers of children with intellectual disability or autism spectrum disorder (ASD) have poorer health than other mothers. Yet no research has explored whether this poorer health is reflected in mortality rates or whether certain causes of death are more likely. We aimed to calculate the hazard ratios for death and for the primary causes of death in mothers of children with intellectual disability or ASD compared to other mothers.

Methods

The study population comprised all mothers of live-born children in Western Australia from 1983–2005. We accessed state-wide databases which enabled us to link socio-demographic details, birth dates, diagnoses of intellectual disability or ASD in the children and dates and causes of death for all mothers who had died prior to 2011. Using Cox Regression with death by any cause and death by each of the three primary causes as the event of interest, we calculated hazard ratios for death for mothers of children intellectual disability or ASD compared to other mothers.

Results and Discussion

During the study period, mothers of children with intellectual disability or ASD had more than twice the risk of death. Mothers of children with intellectual disability were 40% more likely to die of cancer; 150% more likely to die of cardiovascular disease and nearly 200% more likely to die from misadventure than other mothers. Due to small numbers, only hazard ratios for cancer were calculated for mothers of children with ASD. These mothers were about 50% more likely to die from cancer than other mothers. Possible causes and implications of our results are discussed.

Conclusion

Similar studies, pooling data from registries elsewhere, would improve our understanding of factors increasing the mortality of mothers of children with intellectual disability or ASD. This would allow the implementation of informed services and interventions to improve these mothers'' longevity.  相似文献   

9.
Maternal effects are widespread in living organisms though little is known about whether they shape individual affiliative social behavior in primates. Further, it remains a question whether maternal effects on affiliative behavior differ by offspring sex, as they do in other physiological systems, especially in species with high levels of adult sexual dimorphism and divergence in social niches. We explored how direct and indirect experiences of maternal affiliative behavior during infancy predicted affiliative behavior approximately 1–6 years later during the juvenile period, using behavioral data from 41 wild blue monkey juveniles and their 29 mothers, and controlling for individual age, sex, and maternal rank. Female juveniles spent less time grooming with any partner and with peers the more maternal grooming they received during infancy, whereas males groomed more with any partner and with peers. Similarly, the more that mothers groomed with other adult females during subjects’ infancy, female subjects played less with peers, and male subjects played more as juveniles. Further, this maternal effect on social behavior appears specific to early life, as the same aspects of mothers’ sociality measured throughout subjects’ development did not predict juvenile behavior. Overall, our results suggest that both direct and indirect experience of mother's affiliative behavior during infancy influence an individual's affiliation later in life that sexes respond differently to the maternal affiliation, and that the first year of life is a critical window.  相似文献   

10.
Western scholarly literature suggests that (1) weaning is initiated by mothers; (2) weaning takes place within a few days once mothers decide to stop nursing; (3) mothers employ specific techniques to terminate nursing; (4) semi-solid foods (gruels and mashed foods) are essential when weaning; (5) weaning is traumatic for children (it leads to temper tantrums, aggression, etc.); (6) developmental stages in relationships with mothers and others can be demarcated by weaning; and (7) weaning is a process that involves mothers and children exclusively, with weaned children moving from close relationships with their mothers to strengthened relationships with other children. In many respects, these presumptions are consistent with contemporary Euroamerican practices: nursing stops early (usually before six months) relative to other cultures and takes place over a few days or weeks with the help of bottles and baby foods. Because bottles are available, weaning seldom appears traumatic, but it is seen as an important step in the establishment of independence between mothers and infants. By contrast, weaning from the bottle is often perceived as traumatic. Despite considerable academic and popular interest, weaning has seldom been studied systematically, especially in small-scale cultures. Qualitative and quantitative data from a study of Bofi foragers in Central Africa are used here to evaluate the cross-cultural applicability of the assumptions summarized above. Hillary N. Fouts is a Ph.D. student in cultural anthropology at Washington State University, Pullman. Her research interests include breastfeeding, weaning, childfeeding, parenting and alloparenting, cross-cultural child development, and life-history theory. Barry S. Hewlett is a professor of anthropology at Washington State University, Vancouver (Washington). His research interests include paternal involvement, cross-cultural child development, and dual transmission models. Michael E. Lamb is the Head of the Section on Social and Emotional Development at the National Institute of Child Health and Human Development. He has written extensively on parent-child relations in a variety of contexts and cultures.  相似文献   

11.
The Trivers–Willard hypothesis predicts the unequal parental investment between daughters and sons, depending on maternal condition and offspring reproductive potential. Specifically, in polygynous populations where males have higher reproductive variance than females, it predicts that mothers in good condition will invest more in sons, whereas mothers in poor condition will invest more in daughters. Previous studies testing this hypothesis focused on behavioral investment, whereas few examined biological investment. This study investigates the Trivers–Willard hypothesis on both behavioral and biological parental investment by examining breastfeeding frequencies and breast milk fat concentrations. Data from exclusively breastfeeding mothers in Northern Kenya were used to test hypotheses: Economically sufficient mothers will breastfeed sons more frequently than daughters, whereas poor mothers will breastfeed daughters more frequently than sons, and economically sufficient mothers will produce breast milk with higher fat concentration for sons than daughters, whereas poor mothers will produce breast milk with higher fat concentration for daughters than sons. Linear regression models were applied, using breastfeeding frequency or log‐transformed milk fat as the dependent variable, and offspring's sex (son = 1/daughter = 0), socioeconomic status (higher = 1/lower = 0), and the sex‐wealth interaction as the predictors, controlling for covariates. Our results only supported the milk fat hypothesis: infant's sex and socioeconomic status interacted (P = 0.014, n = 72) in their relation with milk fat concentration. The model estimated that economically sufficient mothers produced richer milk for sons than daughters (2.8 vs. 0.6 gm/dl) while poor mothers produced richer milk for daughters than sons (2.6 vs. 2.3 gm/dl). Further research on milk constituents in relation to offspring's sex is warranted. Am J Phys Anthropol , 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

12.
Learning is an important form of phenotypic plasticity that allows organisms to adjust their behaviour to the environment. An individual''s learning performance can be affected by its mother''s environment. For example, mothers exposed to stressors, such as restraint and forced swimming, often produce offspring with impaired learning performance. However, it is unclear whether there are maternal effects on offspring learning when mothers are exposed to ecologically relevant stressors, such as predation risk. Here, we examined whether maternal predator-exposure affects adult offsprings’ learning of a discrimination task in threespined sticklebacks (Gasterosteus aculeatus). Mothers were either repeatedly chased by a model predator (predator-exposed) or not (unexposed) while producing eggs. Performance of adult offspring from predator-exposed and unexposed mothers was assessed in a discrimination task that paired a particular coloured chamber with a food reward. Following training, all offspring learned the colour-association, but offspring of predator-exposed mothers located the food reward more slowly than offspring of unexposed mothers. This pattern was not driven by initial differences in exploratory behaviour. These results demonstrate that an ecologically relevant stressor (predation risk) can induce maternal effects on offspring learning, and perhaps behavioural plasticity more generally, that last into adulthood.  相似文献   

13.
Barred owls (Strix varia) are forest-dwelling owls, native to eastern North America, with populations that expanded westward into the range of the spotted owl (Strix occidentalis). Barred owls exert an overwhelmingly negative influence on spotted owls, thereby threatening spotted owl population viability where the species co-occur. In this review, we provide an overview of the barred owl's range expansion and detail and synthesize previously published literature on spotted and barred owls within the range of the spotted owl as related to potential future outcomes for the northern spotted owl (S. o. caurina). We include research on diet, habitat use and selection, effects of barred owls on spotted owl demography and behavior, hybridization with spotted owls, parasites, contemporary management, and future research needs for spotted owl populations given continued barred owl expansion throughout western North America. Our literature review and synthesis should provide managers with the information necessary to develop strategies that mitigate deleterious effects of barred owls at local and landscape scales. © 2019 The Wildlife Society.  相似文献   

14.
C. Higgins  E. Dunn  D. Conrath 《CMAJ》1981,125(10):1114-1117
The literature indicates that the birth of a sibling and the consequent temporary separation from the mother is usually a stressful experience for a child. It was hypothesized that this stress would result in an increased number of visits by the child to health care facilities because of new health problems. In a controlled study of 89 matched pairs of Indian families in a remote region of northwestern Ontario this hypothesis was not supported. During the intervals studied - the anticipatory period before delivery, the separation itself and the period immediately following the mother''s return home - the number of diagnoses of new medical problems was significantly less for the children who were separated from their mothers for the birth of a sibling. As well, the number of diagnoses of new medical problems in the children separated form their mothers decreased over the three intervals. The fathers'' reluctance to seek health care probably played a major role in this decrease.  相似文献   

15.
16.
Skinfold thickness measurements were made at biceps, triceps, subscapular, and suprailiac sites on both sides on 265 full-term newborn infants. The mothers were classified as thin (25), normal (179), or obese (61) on the basis of their triceps skinfold thicknesses. At all skinfold sites the babies of the obese mothers were significantly fatter than the babies of normal mothers, and the babies of the normal mothers were significantly fatter than those of the thin mothers. There was a highly significant positive correlation between maternal triceps thickness and the baby''s sum of skinfold thicknesses. Hypertension was common during the pregnancies of the obese mothers and was associated with a significant reduction in the babies'' skinfold thicknesses. When each of the 61 obese mothers were matched for parity, blood pressure, and smoking habit with 61 non-obese mothers the babies of the obese mothers still had significantly greater skinfold thicknesses than the babies of non-obese mothers.  相似文献   

17.

Background

Childhood fevers due to malaria remain a major cause of morbidity and mortality among under-five children in Nigeria. The degree of vulnerability perceived by mothers will affect their perception of the severity and threat of their child''s fever and the patterns of health care use. This study was undertaken to compare maternal responses to childhood fever in urban and rural areas of Enugu, south east Nigeria.

Methodology/Principal Findings

Data was collected with pre-tested interviewer-administered questionnaires from 276 and 124 urban and rural households respectively. In each household, only one woman aged 15–49 years who had lived in each of the urban and rural communities for at least one year and had at least one child less than 5 years old was interviewed. Malaria was mentioned as the commonest cause of childhood fevers. Rural mothers were more likely to recognize danger signs and symptoms than urban mothers. Rural mothers use more of informal than formal health services, and there is more home management of the fever with urban than rural mothers. Chloroquine, ACT, SP and Paracetamol are the main drugs given at home for childhood fevers, but the rural mothers were more likely to use leftover drugs from previous treatment to treat the fevers than urban mothers. The urban respondents were also more likely to use a preventive measure. Urban mothers sought actions faster than rural mothers and the total cost of treatment was also higher in urban areas.

Conclusions/Significance

Both urban and rural mothers are aware that malaria is the major cause of childhood fevers. Although rural mothers recognize childhood fever and danger signs better than urban mothers, the urban mothers'' responses to fever seem to be better than that for rural mothers. These responses and differences may be important for geographical targeting by policy makers for malaria interventions.  相似文献   

18.
Breastfeeding has immense public health value for mothers, babies, and society. But there is an undesirably large gap between the number of new mothers who undertake and persist in breastfeeding compared to what would be a preferred level of accomplishment. This gap is a reflection of the many obstacles, both physical and psychological, that confront new mothers. Previous research has illuminated many of these concerns, but research on this problem is limited in part by the unavailability of a research instrument that can measure the key differences between first-time mothers and experienced mothers, with regard to the challenges they face when breastfeeding and the instructional advice they require. An instrument was designed to measure motivational complexity associated with sustained breast feeding behaviour; the Breastfeeding Motivational Measurement Scale. It contains 51 self-report items (7 point Likert scale) that cluster into four categories related to perceived value of breast-feeding, confidence to succeed, factors that influence success or failure, and strength of intentions, or goal. However, this scale has not been validated in terms of its sensitivity to profile the motivation of new mothers and experienced mothers. This issue was investigated by having 202 breastfeeding mothers (100 first time mothers) fill out the scale. The analysis reported in this paper is a three factor solution consisting of value, midwife support, and expectancies for success that explained the characteristics of first time mothers as a known group. These results support the validity of the BMM scale as a diagnostic tool for research on first time mothers who are learning to breastfeed. Further research studies are required to further test the validity of the scale in additional subgroups.  相似文献   

19.
Abstract

This study was an attempt to further investigate Adamchak's (1977) findings that women whose mothers had been employed around the time the respondent was sixteen had a higher ideal family size than those women whose mothers had not worked. During the research, it was discovered that the Adamchak results were not replicable. However, it was also noted that different ways of handling the response category of “As many as you want” (children) produced markedly different results.  相似文献   

20.
《Animal behaviour》1988,36(5):1472-1481
The impact of seasonal mating on the mother-infant relationship during the first year of the infant's life was documented in a confined troop of Japanese macaques. During the weeks in which the mothers were being mounted, negative behaviour directed towards the infants increased. As maternal rejections and punishments escalated, the infants displayed regressive behaviour (showing signs of distress more frequently). Infants also groomed their mothers at an increased rate at this time. Behaviour that indicated increased independence did not show increases during this time. Moreover, behaviour negatively associated with independence, such as ventral contact and proximity to the mother, remained stable throughout this time period. The mother-infant relationship undergoes a period of conflict during the mating season not because the mother is weaning her infant, but because it is to her reproductive advantage to regulate the times in which the infant is allowed to suckle.  相似文献   

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