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1.
Some commentators believe that persons facing imminent death are incapable of making autonomous, informed decisions about whether to enter high-risk, end-of-life research trials. Using the AbioCor artificial heart trial as an example, this essay argues to the contrary. Although some people are incapacitated, many are capable of making such decisions. To forbid dying people to make a decision about whether to enter a clinical trial may insult deeply held personal values at a time when honoring those values may be most important. Moreover, to deny dying persons entry into high-risk clinical trials leaves ethically worse alternatives: using healthier people, requiring surrogates to decide even when the patient is competent, or simply forgoing all research featuring high-risk, potentially life-saving interventions. Once we agree that it is at least sometimes acceptable to permit dying persons to choose high-risk research, a number of practical safeguards can be implemented to ameliorate the challenges that can hinder decision making in this difficult area.  相似文献   

2.
Introduction: The effectiveness of colorectal cancer (CRC) screening programs depends on repeated participation. Little is known on later rounds in programs that use the fecal immunochemical test (FIT), in particular whether previous participants are likely to participate again, and if non-participants persist in declining. We compared overall participation in a second round to that in a first round, and evaluated differences in participation rates based on previous response. Methods: Asymptomatic persons aged 50–74 years were invited to a second round of a FIT-based CRC screening pilot. We assessed the participation rate overall and within second round subgroups of previous participants, previous non-participants, and first time invitees. We also assessed whether participation rates were similar for males and females and for age groups. Results: In the first screening round, 2871 of 5309 invitees returned the FIT (participation rate of 57%). This was higher than in the second in which 3187 of 5925 participated (54%; p = 0.0008). Second round participation rate was 85% (2034/2385) among previous participants, 18% (325/1826) among previous non-participants and 48% (828/1714) among first time invitees (p < .0001). Overall, males and persons aged under 55 were less likely to participate. Conclusions: Participation in a second round of FIT-screening was significantly lower than in the first round, largely due to a drop in participation in first round participants, and a relatively low response among first time invitees. This loss of uptake was partially compensated by a willingness to be screened in previous non-participants.  相似文献   

3.

Objective

Decision making is an important determinant of health and well-being across the lifespan but is critical in aging, when many influential decisions are made just as cognitive function declines. Increasing evidence suggests that older adults, even those without dementia, often make poor decisions and are selectively vulnerable to scams. To date, however, the factors associated with poor decision making in old age are unknown. The objective of this study was to test the hypothesis that poor decision making is a consequence of cognitive decline among older persons without Alzheimer’s disease or mild cognitive impairment.

Methods

Participants were 420 non-demented persons from the Memory and Aging Project, a longitudinal, clinical-pathologic cohort study of aging in the Chicago metropolitan area. All underwent repeated cognitive evaluations and subsequently completed assessments of decision making and susceptibility to scams. Decision making was measured using 12 items from a previously established performance-based measure and a self-report measure of susceptibility to scams.

Results

Cognitive function data were collected over an average of 5.5 years prior to the decision making assessment. Regression analyses were used to examine whether the prior rate of cognitive decline predicted the level of decision making and susceptibility to scams; analyses controlled for age, sex, education, and starting level of cognition. Among 420 persons without dementia, more rapid cognitive decline predicted poorer decision making and increased susceptibility to scams (p’s<0.001). Further, the relations between cognitive decline, decision making and scams persisted in analyses restricted to persons without any cognitive impairment (i.e., no dementia or even mild cognitive impairment).

Conclusions

Poor decision making is a consequence of cognitive decline among older persons without Alzheimer’s disease or mild cognitive impairment, those widely considered “cognitively healthy.” These findings suggest that even very subtle age-related changes in cognition have detrimental effects on judgment.  相似文献   

4.
Wealth, Status, and Reproductive Success among the Mukogodo of Kenya   总被引:4,自引:0,他引:4  
Lee  Cronk 《American anthropologist》1991,93(2):345-360
The evolutionary biological hypothesis that culturally defined values and goals are proximate means of enhancing reproductive success is tested on data from the Mukogodo, a small group of Maa-speaking pastoralists in north-central Kenya who value the accumulation of livestock. The results support the prediction that, at least among males, livestock wealth should correlate with reproductive success. This correlation appears to be due mainly to greater polygyny among wealthier men. Lower age at first marriage among wealthier men may also contribute to the correlation between livestock wealth and reproductive success. The association between livestock wealth and reproductive success does not appear to be due to the productivity of wives and children, to bridewealths obtained when daughters marry, or to the effects of wealth on the reproductive success of men's wives.  相似文献   

5.
6.
This article describes to what degree socio-economic differences exist among community living older men and women, and to what degree these differences are to be explained by health, behaviour, childhood and psychosocial conditions. The data are available from 1427 men and 1503 women (aged 55-85), participating in the Longitudinal Aging Study Amsterdam (LASA) in 1992/1993. As indicators of socio-economic status (ses) we used the highest level of education and net monthly income. Age-adjusted mortality risks for men and women with low income and for men with a low level of education are about 1.5 times as high as for to the persons with high income and educational level. Among men, but not among women, the difference in mortality risk between low and high status persons remains after adjustment for age, health status, and several risk factors. Differences in lifestyle, parental ses and psychosocial characteristics explain little to nothing of the age-adjusted ses-differentiation in mortality. It is concluded that ses-inequalities in mortality are present among Dutch men and, to a lesser extent among women, until high age, and are partly explained by the relatively large health problems of the lower status group.  相似文献   

7.

Background

This paper explores the framings of trypanosomiasis, a widespread and potentially fatal zoonotic disease transmitted by tsetse flies (Glossina species) affecting both humans and livestock. This is a country case study focusing on the political economy of knowledge in Zambia. It is a pertinent time to examine this issue as human population growth and other factors have led to migration into tsetse-inhabited areas with little historical influence from livestock. Disease transmission in new human-wildlife interfaces such as these is a greater risk, and opinions on the best way to manage this are deeply divided.

Methods

A qualitative case study method was used to examine the narratives on trypanosomiasis in the Zambian policy context through a series of key informant interviews. Interviewees included key actors from international organisations, research organisations and local activists from a variety of perspectives acknowledging the need to explore the relationships between the human, animal and environmental sectors.

Principal Findings

Diverse framings are held by key actors looking from, variously, the perspectives of wildlife and environmental protection, agricultural development, poverty alleviation, and veterinary and public health. From these viewpoints, four narratives about trypanosomiasis policy were identified, focused around four different beliefs: that trypanosomiasis is protecting the environment, is causing poverty, is not a major problem, and finally, that it is a Zambian rather than international issue to contend with. Within these narratives there are also conflicting views on the best control methods to use and different reasoning behind the pathways of response. These are based on apparently incompatible priorities of people, land, animals, the economy and the environment. The extent to which a One Health approach has been embraced and the potential usefulness of this as a way of reconciling the aims of these framings and narratives is considered throughout the paper.

Conclusions/Significance

While there has historically been a lack of One Health working in this context, the complex, interacting factors that impact the disease show the need for cross-sector, interdisciplinary decision making to stop rival narratives leading to competing actions. Additional recommendations include implementing: surveillance to assess under-reporting of disease and consequential under-estimation of disease risk; evidence-based decision making; increased and structurally managed funding across countries; and focus on interactions between disease drivers, disease incidence at the community level, and poverty and equity impacts.  相似文献   

8.
The giant freshwater prawn, Macrobrachium rosenbergii, is a large shrimp extensively used in aquaculture whose grooming behaviors were analyzed in this study. Macrobrachium rosenbergii exhibits three unique male morphotypes that differ in their behavior, morphology and physiology: small-clawed males (SM), orange-clawed males (OC) and blue-clawed males (BC). The largest and most dominant males, BC males, are predicted to have significantly different grooming behaviors compared to females and the other two male morphotypes. These BC males may be too large and bulky to efficiently groom and may dedicate more time to mating and agonistic interactions than grooming behaviors. Observations were conducted to look at the prevalence of grooming behaviors in the absence and presence of conspecifics and to determine if any differences in grooming behavior exist among the sexes and male morphotypes. Significant differences in the grooming behaviors of all individuals (females and male morphotypes) were found. BC males tended to have the highest grooming time budget (percent of time spent grooming) while SM males had a relatively low grooming time budget. The grooming behaviors of the male morphotypes differed, indicating while these males play distinct, separate roles in the social hierarchy, they also have different grooming priorities. The conditions in which Macrobrachium rosenbergii are cultured may result in increased body fouling, which may vary, depending on the grooming efficiencies and priorities of these male morphotypes. Overall, grooming behaviors were found to be a secondary behavior which only occurred when primary behaviors such as mating, feeding or fighting were not present.  相似文献   

9.
During foraging, worker ants are known for making use of many information sources to guide themselves in external environments, especially individual (memory) and social (trail pheromone) information. Both kinds of information act in a synergic way, keeping the foraging process efficient and organized. However, when social and individual information is conflicting face a trail bifurcation, it is necessary to establish a hierarchical order so prioritizing one of them. This study aims to verify which information (social or individual) is prioritized by Acromyrmex subterraneus workers when facing a bifurcation in a Y-trail system. Only one branch of the Y-trail leads to food resource and it had a section covered by filter paper where trail pheromone was deposited by workers. Pheromone deposition was here estimated by worker flow. After an individually marked forager (target-worker) made 1, 3 or 5 trips to the food resource, the filter paper was transferred to the branch which did not lead to the food. The time spent by target workers on branch selection and their right choice (branch with food) frequency were registered. Regardless of the target worker's previous trips to the resource, right choice frequency stood over 70%. In addition, the number of previous trips did not influence the time spent on decision making. However, the higher the flow of workers, the longer the time spent on decision making. By simulating a situation with conflicting information, it was possible to verify that a hierarchical order is established by A. subterraneus, which prioritized individual information (memory).  相似文献   

10.
As livestock disease control programs in Africa begin to rely more upon para-professionals and livestock producers as deliverers of animal health care services, understanding the role different household members play in providing animal health care becomes increasingly important. This paper presents a framework for the analysis of gender aspects of livestock disease control based on a similar framework developed by Feldstein and Poats (1989). The utility of this framework is illustrated using household-level data collected from a district in central Kenya. Adult women and elderly men in the sample have primary responsibility for livestock care, and are therefore well placed to diagnose illness. Dipping and spraying of animals to prevent tick-borne and other diseases is the primary responsibility of adult males. Decisions regarding use of milk from the morning milking are more likely to be made by adult men. It is morning milk that is most often sold. Adult women, however, make decisions about use of evening milk, which is most often kept for household consumption. Knowledge of livestock diseases did not appear to vary significantly by gender, although some elderly men did possess extensive knowledge of indigenous disease categories and traditional remedies. The importance of recognizing gender issues in planning and implementing livestock disease control programs is discussed.  相似文献   

11.
《Animal behaviour》1986,34(6):1680-1686
Traditional theoretical accounts of crustacean mate guarding have assumed that changes associated with the female's reproductive state elicit the mate guarding behaviour of the male. The present study systematically examined the effects of both the male and female reproductive states on the precopulatory mate guarding decision of the amphipod Gammarus lawrencianus. Independent manipulation of the male and female variables indicated that both contributed additively to the probability of precopulatory mate guarding. When considered together, the results demonstrate that females that are closer to the post-moult copulation state are more likely to be guarded; and that males are more likely to enter the mate guarding relationship as the time since their last copulation increases. An adequate theoretical account of crustancean precopulatory mate guarding must, therefore, consider the contribution of both the male and the female reproductive states to the mate guarding decision.  相似文献   

12.
Two hundred fourteen serosamples were collected from four livestock species across five ranches in Laikipia County, Kenya. Serological analysis for Coxiella burnetii (the causative agent for Q fever) showed a distinct seroprevalence gradient: the lowest in cattle, higher in sheep and goats, and the highest in camels. Laikipia-wide aerial counts show a recent increase in the camel population. One hundred fifty-five stakeholder interviews revealed concern among veterinary, medical, ranching, and conservation professionals about Q fever. Local pastoralists and persons employed as livestock keepers, in contrast, revealed no knowledge of the disease. This work raises questions about emerging Q fever risk in Laikipia County and offers a framework for further integrative disease research in East African mixed-use systems.  相似文献   

13.
Differences among females in infant survival can contribute substantially to variance in fitness. Infant survival is a product of external risk factors and investment by kin, especially the mother, and is thus closely tied with the evolution of behavior and life history. Here we present a 9-yr study (2004–2012) of infant survival and sex ratio relative to age and dominance ranks of mothers and the presence of immigrant males in a free-ranging population of gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We consider immigrant males because they are known to increase infant mortality in several other species. We found that infants of older mothers had higher survival than those of younger mothers but that high rank did not confer a significant benefit on infant survival. Female infants had higher survival than male infants. Young, low-ranking females had more male infants than young, high-ranking females, which had slightly more daughters, but this difference declined as females aged because low-ranking females had more daughters as they aged. With limited data, we found a significant relationship between the presence of male immigrants and infant mortality (falls and unexplained disappearances) to 18 mo. Our results suggest that infant survival in gray-cheeked mangabeys is most precarious when mothers must allocate energy to their own growth as well as to their infants, that sons of young mothers are at greatest risk, and that immigrant males can negatively affect infant survival.  相似文献   

14.
Abstract

Relatively little is known about the motivational antecedents to the use of assisted reproductive technology (ART). In this paper we measure the fertility motivations of infertile couples who are considering the use of ART, using an established instrument, the Childbearing Questionnaire (CBQ). Our sample consists of 214 men and 216 women who were interviewed at home after an initial screening for ART but before making a final decision. We conducted two sets of analyses with the obtained data. In one set, we compared the scores on scales and subscales of the CBQ for the males and females in our sample with the scores for males and females from a comparable normative sample. For these analyses we first examined sample and gender differences with a four‐group analysis of variance. We then conducted a series of linear models that included background characteristics as covariates and interactions between sample, gender, and age and between those three variables and the background characteristics. The results showed the expected higher positive and lower negative motivations in the ART sample and a significant effect on positive motivations of the interaction between sample and age. In the second set of analyses, we developed several new subscales relevant to facets of the desire for a child that appear to be important in ART decision‐making. These facets include the desire to be genetically related to the child and the desire to experience pregnancy and childbirth. A third facet, the desire for parenthood, is already well covered by the existing subscales. The results showed the new subscales to have satisfactory reliability and validity. The results also showed that the original and new subscales predicted the three facets of the desire for a child in a multivariate context We conclude with a general discussion of the way our findings relate both to ART decision‐making and to further research on the motivations that drive it.  相似文献   

15.
Biologists have long been interested in intransitive preferences: circular preferences in which options cannot be ranked and no single option dominates, similar to a game of rock‐paper‐scissors. Intransitive preferences violate rational decision‐making, an assumption made by models of evolution by mate choice. Despite its potential importance in the study of sexual selection, few studies have tested for intransitive preferences. Even fewer have asked whether females differ in whether they choose mates transitively or intransitively and what factors might predict (in)transitive choice. Though intransitive choice is thought to be more common as options become more complex, this prediction is untested in animals. To fill this gap, we tested whether female Xiphophorus nigrensis swordtails can rank digitally animated males differing in size, courtship intensity, or both size and courtship intensity, and whether female responses were predicted by a female's age. Females choosing among males that varied only in size showed higher than expected levels of intransitivity, whereas females choosing among males that varied in their courtship or both properties did not. Older females were more likely to be irrational than younger females when evaluating male size, suggesting that experience modifies transitive decision‐making processes. These results show that mate choice irrationality may vary by a female's experience and the signal characteristics during decision‐making.  相似文献   

16.
Abstract

This paper examines the degree of preoperative ambivalence expressed by 255 currently married tubal ligation patients compared to 167 wives of vasectomy patients regarding the decision to terminate childbearing and aspects of the decision‐making process which account for differences between groups. Data indicate that tubal ligation women are significantly more certain and comfortable with their decision than are vasectomy wives. In order to explain this finding, analysis focused on sociodemographic factors; time factors related to the decision; variables related to communication with spouse and others; factors internal to the individual, including interest in another child and motivation for the decision; external constraints on the decision; and couple dynamics in the decision‐making process. Results indicate that group differences in ambivalence are primarily due to the effects of strong male control over the termination decision, as perceived by the wife, and a disproportionate prevalence of this pattern among vasectomy couples. An interaction effect between male dominance and group membership was also found. Implications of study results for preoperative counseling, including likely sources of future regret, are considered.  相似文献   

17.
Decision making process is an important component of information use by animals and has already been studied in natural situations. Decision making takes time, which is expressed as a cost in evolutionary explanations of decision making abilities of animals. However, the duration of information assessment and decision making process has not been measured in a natural situation. Here, we use responses of wild magpies (Pica pica) to predictably approaching humans to demonstrate that, regardless of whether the bird perceived high (decided to fly away) or low (resumed foraging) threat level, the bird assessed the situation faster when approaching humans looked directly at it than when the humans were not directly looking at it. This indicates that prey is able to extract more information about the predator’s intentions and to respond sooner when the predator is continuously (“intently”) looking at the prey. The results generally illustrate how an increase of information available to an individual leads to a shorter assessment and decision making process, confirming one of central tenets of psychology of information use in a wild bird species in its natural habitat.  相似文献   

18.
Background: The disparity in breast cancer mortality rates among white and black US women is widening, with higher mortality rates among black women. We apply functional time series models on age-specific breast cancer mortality rates for each group of women, and forecast their mortality curves using exponential smoothing state-space models with damping. Materials and Methods: The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program of the US [1]. Mortality data were obtained from the National Centre for Health Statistics (NCHS) available on the SEER*Stat database. We use annual unadjusted breast cancer mortality rates from 1969 to 2004 in 5-year age groups (45–49, 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84). Age-specific mortality curves were obtained using nonparametric smoothing methods. The curves are then decomposed using functional principal components and we fit functional time series models with four basis functions for each population separately. The curves from each population are forecast and prediction intervals are calculated. Results: Twenty-year forecasts indicate an overall decline in future breast cancer mortality rates for both groups of women. This decline appears to be steeper among white women aged 55–73 and black women aged 60–84. For black women under 55 years of age, the forecast rates are relatively stable indicating there is no significant change in future breast cancer mortality rates among young black women in the next 20 years. Conclusion: White women have smooth and consistent patterns in breast cancer mortality rates for all age-groups whereas the mortality rates for black women are much more variable. The projections suggest, for some age groups, black American women may not benefit equally from the overall decline in breast cancer mortality in the United States.  相似文献   

19.
Collective behavior has recently attracted a great deal of interest in both natural and social sciences. While the role of leadership has been closely scrutinized, the rules used by joiners in collective decision making have received far less attention. Two main hypotheses have been proposed concerning these rules: mimetism and quorum. Mimetism predicts that individuals are increasingly likely to join collective behavior as the number of participants increases. It can be further divided into selective mimetism, where relationships among the participants affect the process, and anonymous mimetism, where no such effect exists. Quorum predicts that a collective behavior occurs when the number of participants reaches a threshold. To probe into which rule is used in collective decision making, we conducted a study on the joining process in a group of free-ranging Tibetan macaques (Macaca thibetana) in Huangshan, China using a combination of all-occurrence and focal animal sampling methods. Our results show that the earlier individuals joined movements, the more central a role they occupied among the joining network. We also found that when less than three adults participated in the first five minutes of the joining process, no entire group movement occurred subsequently. When the number of these early joiners ranged from three to six, selective mimetism was used. This means higher rank or closer social affiliation of early joiners could be among the factors of deciding whether to participate in movements by group members. When the number of early joiners reached or exceeded seven, which was the simple majority of the group studied, entire group movement always occurred, meaning that the quorum rule was used. Putting together, Macaca thibetana used a combination of selective mimetism and quorum, and early joiners played a key role in deciding which rule should be used.  相似文献   

20.
BackgroundCoxiella burnetii is a widely distributed pathogen, but data on its epidemiology in livestock, and human populations remain scanty, especially in developing countries such as Kenya. We used the One Health approach to estimate the seroprevalance of C. burnetii in cattle, sheep, goats and human populations in Tana River county, and in humans in Garissa county, Kenya. We also identified potential determinants of exposure among these hosts.MethodsData were collected through a cross-sectional study. Serum samples were taken from 2,727 animals (466 cattle, 1,333 goats, and 928 sheep) and 974 humans and screened for Phase I/II IgG antibodies against C. burnetii using enzyme-linked immunosorbent assay (ELISA). Data on potential factors associated with animal and human exposure were collected using a structured questionnaire. Multivariable analyses were performed with households as a random effect to adjust for the within-household correlation of C. burnetii exposure among animals and humans, respectively.ResultsThe overall apparent seroprevalence estimates of C. burnetii in livestock and humans were 12.80% (95% confidence interval [CI]: 11.57–14.11) and 24.44% (95% CI: 21.77–27.26), respectively. In livestock, the seroprevalence differed significantly by species (p < 0.01). The highest seroprevalence estimates were observed in goats (15.22%, 95% CI: 13.34-17.27) and sheep (14.22%, 95% CI: 12.04–16.64) while cattle (3.00%, 95% CI: 1.65–4.99) had the lowest seroprevalence. Herd-level seropositivity of C. burnetii in livestock was not positively associated with human exposure. Multivariable results showed that female animals had higher odds of seropositivity for C. burnetii than males, while for animal age groups, adult animals had higher odds of seropositivity than calves, kids or lambs. For livestock species, both sheep and goats had significantly higher odds of seropositivity than cattle. In human populations, men had a significantly higher odds of testing positive for C. burnetii than women.ConclusionsThis study provides evidence of livestock and human exposure to C. burnetii which could have serious economic implications on livestock production and impact on human health. These results also highlight the need to establish active surveillance in the study area to reduce the disease burden associated with this pathogen.  相似文献   

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