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Age Differences (age + difference)
Selected AbstractsSex, Rank and Age Differences in the Japanese Macaque (Macaca fuscata yakui) Participation in Inter-Group EncountersETHOLOGY, Issue 5 2005Bonaventura Majolo In many species interactions among group are often characterized by agonistic behaviour. Although animals may participate in inter-group encounters in different ways, depending on their energetic requirements, reproductive tactics, and/or developmental stage, the proximate causes affecting an animal's participation in inter-group encounters are still poorly understood. Indeed, many studies have analysed the behaviour of males and females during inter-group encounters without considering the importance of additional factors (e.g. rank). This study focuses on wild non-provisioned Japanese macaques (Macaca fuscata yakui) living on Yakushima Island, Japan. It aims to determine how monkeys of different sex, age, and rank behave during inter-group encounters and it discusses the implications and consequences of their behaviour on group composition and male dispersal. Males participated significantly more than females in inter-group encounters, by displaying more aggressive or affiliative behaviour. High-ranking and/or adult males were more aggressive than low-ranking and/or subadult males during encounters occurring in the mating season and they also showed more herding behaviour. This trend was not found in inter-group encounters occurring during the non-mating season. Finally, males which then emigrated to new groups were low-ranking and/or subadult individuals. Those males displayed more affiliative behaviour towards foreign males than males which did emigrate. These data indicate that in non-territorial species with male dominance over female and high competition for mating partners males play an active, and often aggressive, role during inter-group encounter while female participation is scarce. Factors such as age, rank and period of the year (in seasonally breeding species) have to be taken into considerations when analysing interactions between groups and their effects on group composition and social behaviour. [source] Age Differences in the Responses to Adult and Juvenile Alarm Calls by Bonnet Macaques (Macaca radiata)ETHOLOGY, Issue 2 2000Uma Ramakrishnan This study examined the differential responses to alarm calls from juvenile and adult wild bonnet macaques (Macaca radiata) in two parks in southern India. Field studies of several mammalian species have reported that the alarm vocalizations of immature individuals are often treated by perceivers as less provocative than those of adults. This study documents such differences in response using field-recorded playbacks of juvenile and adult alarm vocalizations. To validate the use of playback vocalizations as proxies of natural calls, we compared the responses of bonnet macaques to playbacks of alarm vocalizations with responses engendered by natural alarm vocalizations. We found that the frequency of flight, latency to flee, and the frequency of scanning to vocalization playbacks and natural vocalizations were comparable, thus supporting the use of playbacks to compare the effects of adult and juvenile calls. Our results showed that adult alarm calls were more provocative than juvenile alarm calls, inducing greater frequencies of flight with faster reaction times. Conversely, juvenile alarm calls were more likely to engender scanning by adults, a result interpreted as reflecting the lack of reliability of juvenile calls. Finally, we found age differences in flight behavior to juvenile alarm calls and to playbacks of motorcycle engine sounds, with juveniles and subadults more likely to flee than adults after hearing such sounds. These findings might reflect an increased vulnerability to predators or a lack of experience in young bonnet macaques. [source] Modeling Age Differences in Infant Category LearningINFANCY, Issue 2 2004Thomas R. Shultz We used an encoder version of cascade correlation to simulate Younger and Cohen's (1983, 1986) finding that 10-month-olds recover attention on the basis of correlations among stimulus features, but 4- and 7-month-olds recover attention on the basis of stimulus features. We captured these effects by varying the score threshold parameter in cascade correlation, which controls how deeply training patterns are learned. When networks learned deeply, they showed more error to uncorrelated than to correlated test patterns, indicating that they abstracted correlations during familiarization. When prevented from learning deeply, networks decreased error during familiarization and showed as much error to correlated as to uncorrelated tests but less than to test items with novel features, indicating that they learned features but not correlations among features. Our explanation is that older infants learn more from the same exposure than do younger infants. Unlike previous explanations that postulate unspecified qualitative shifts in processing with age, our explanation focuses on quantitatively deeper learning with increasing age. Finally, we provide some new empirical evidence to support this explanation. [source] An Empirical Analysis of 30 Years of U.S. Juvenile and Adult Sexual Homicide Offender Data: Race and Age Differences in the Victim,Offender RelationshipJOURNAL OF FORENSIC SCIENCES, Issue 5 2010Heng Choon (Oliver) Chan M.A. Abstract:, Little is known about the racial patterns of crimes committed by sexual homicide offenders (SHOs). This study examined race and age influences on victim,offender relationship for juvenile and adult SHOs. A large sample (N = 3868) from the Supplemental Homicide Reports (1976,2005) was used. Analyses of victim,offender patterns included examining victim age effects (child, adolescent, adult, and elderly). The findings revealed several race- and age-based differences. Black offenders were significantly overrepresented in the SHO population. This finding held for juveniles and adults independently. White SHOs were highly likely to kill within their race, "intra-racially" (range 91,100%) across four victim age categories, whereas Black SHOs killed both intra-racially (range 24,82%) and inter-racially (18,76%), with the likelihood of their killing inter-racially increasing as the age of the victim increased. This study underscores the importance of considering victim,offender racial patterns in sexual murder investigations, and it offers practical implications for offender profiling. [source] Age Differences in Conservatism: Evidence on the Mediating Effects of Personality and Cognitive StyleJOURNAL OF PERSONALITY, Issue 1 2009Ilse Cornelis ABSTRACT The present study investigates the commonly found age,conservatism relationship by combining insights from studies on the development of personality and motivated social cognition with findings on the relationships between these factors and conservative beliefs. Based on data collected in Belgium (N=2,373) and Poland (N=939), we found the expected linear effect of age on indicators of social-cultural conservatism in Belgium and Poland and the absence of such effects for indicators of economic-hierarchical conservatism. We further demonstrated that these effects of age on indicators of cultural conservatism in both countries were (in part) mediated through the personality factor Openness to Experience and the motivated cognition variable Need for Closure. The consistency of these findings in two countries with a very dissimilar sociopolitical history attests to the importance of the developmental perspective for the study of the relationship between age and conservatism. [source] Inference generation in young, young,old and old,old adults: evidence for semantic architecture stabilityAPPLIED COGNITIVE PSYCHOLOGY, Issue 2 2008Debra McGinnis Participants (31 young, 27 young,old, and 28 old,old) read 12 narratives, pausing periodically to think aloud. The resulting protocols were analysed for 17 types of inferences and for non-content (off-target) information. Factor analysis yielded three inference factors: character, causal and physical. Age difference across these factors were not significant, suggesting that inferential processing architecture may be stable. Each narrative also included an unfamiliar word. Immediately following each narrative, four definition choices and a definition rating scale were presented. The definition scores of old,old adults were lower than young and young,old. In addition, definition scores were negatively related to non-content comment counts. Taken together, these findings suggest that off-target working-memory intrusions may interfere with interpretation specificity in older adults even though semantic architecture remains stable. This study extends the aging and inference literature by addressing age-related changes across categories of inferential processing and by including a sample of old,old adults. Copyright © 2007 John Wiley & Sons, Ltd. [source] Neural correlates of successful and partial inhibitions in children: An ERP studyDEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2009Lucy Cragg Abstract This experiment used event-related potentials (ERPs) to investigate the neural processes underlying the development of response inhibition in a modified version of the go/no-go paradigm [Cragg and Nation [2008] Developmental Science 11(6): 819,827]. N2 and P3 ERP components on correct go trials and partial and successful inhibitions were compared in 7- and 9-year-old children. A larger N2 effect on successful inhibitions was found in 9-year-olds compared to 7-year-olds at fronto-central electrodes. N2 amplitude was positively related to behavioral performance in the 7-year-olds suggesting it may reflect inhibitory processes; however, this relationship was not present in the 9-year-olds. Age differences were also apparent in the go P3, perhaps indicating differences in stimulus processing. The no-go P3 component was larger on successful than partial inhibitions. In contrast, there was no difference in N2 amplitude between partial and successful inhibitions. A significant difference was found in N2 latency however. This suggests that inhibitory processes are similar in both cases but initiated earlier on successful inhibitions. N2 latency was also shorter in 9-year-olds than 7-year-olds supporting an increase in the efficiency of response inhibition with age. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 533,543, 2009. [source] Bone weight: new reference values based on a modern Portuguese identified skeletal collectionINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2009A. M. Silva Abstract Skeletal weight and/or weight of the different bones of the human skeleton are currently used in a wide range of applications such as archaeological cremations and forensics. Still, few reference values are available that compare the mean weights for the different skeletal parts. In this paper we present new reference values for total skeletal weight, including the weight of the different skeletal bones based on a modern Portuguese Identified Skeletal Collection (CEI) curated in the Museum of Anthropology of the University of Coimbra (Portugal). The mean weight of the entire skeleton for the CEI pooled sample is 3323.8,±,779.6,g. Sex and age differences were investigated. As expected, males display heavier bones, at a statistically significant level. The mean weight of the male skeletons is 3850,g, and 2797.6,g for the female sample. Age differences were found, especially for the female samples in the 29,39 versus 50,59,and/or >60 age groups, probably as a consequence of age-related bone loss in post-menopausal women. For the male sample, no clear age-related trend was observed but for the unexpected result that the second highest bone weight recorded is in the oldest age group (>60 years). This could result from high mechanical loadings and thus greater bone robusticy and amount of cortical bone. The percentage of weight of the different parts of the skeleton was also calculated. These new values can be quite useful in the study of very fragmentary and/or commingled human remains, recovered from historic or forensic contexts, since the complete identification, by side, of the remains is not necessary. Copyright © 2008 John Wiley & Sons, Ltd. [source] Age differences in career activities among higher-level employees in the Netherlands: a comparison between profit sector and non-profit sector staffINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 2 2006Beatrice Isabella Johanna Maria Van Der Heijden The present study describes age differences in the occurrence of career activities among profit sector and non-profit sector employees in the Netherlands. Three different types of variables have been studied, i.e. individual, job-related and organizational variables. Hypotheses have been tested with original survey data from 423 profit sector employees and 136 non-profit sector employees. The employees are all working in higher-level jobs in large organizations. Overall, we may conclude from this study that the differences between profit sector and non-profit sector workers are not consistent at all. For some factors the situation is more advantageous for profit sector employees, whereas for other factors the outcomes point in the opposite direction. Regarding age effects, we have found that, in general, for profit sector employees the differences between starters (20,34 years) and middle-aged workers (35,49 years) are not univocal, whereas the differences between middle-aged workers and seniors (over-fifties) imply that the amount of individual initiatives and organizational activities is less for the latter group of employees. When the three age groups are compared for the non-profit sector employees, most factors do not vary significantly. For the factors where the F-test is found to be significant, by and large, the situation regarding the possibilities for a further career development is worst for the seniors. [source] Association Between Testosterone and Estradiol and Age-Related Decline in Physical Function in a Diverse Sample of MenJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2008Andre B. Araujo PhD OBJECTIVES: To examine the association between aging and physical function in men by testing a theoretically based model of aging, hormones, body composition, strength, and physical function with data obtained from men enrolled in the Boston Area Community Health/Bone (BACH/Bone) Survey. DESIGN: Cross-sectional, observational survey. SETTING: Population-based. PARTICIPANTS: Eight hundred ten black, Hispanic, and white randomly selected men from the Boston area aged 30 to 79. MEASUREMENTS: Testosterone, estradiol, sex hormone,binding globulin, lean and fat mass, grip strength, and summated index of physical function (derived from walk and chair stand tests). RESULTS: Measures of grip strength and physical function declined strongly with age. For instance, 10 years of aging was associated with a 0.49-point difference (scale 0,7) in physical function. Age differences in total testosterone and estradiol concentrations were smaller than age differences in their free fractions. Weak or nonsignificant age-adjusted correlations were observed between hormones and measures of physical function, although path analysis revealed a positive association between testosterone and appendicular lean mass and a strong negative association between testosterone and total fat mass. Lean and fat mass, in turn, were strongly associated with grip strength and physical function, indicating the possibility that testosterone influences physical function via indirect associations with body composition. CONCLUSION: The age-related decline in serum testosterone concentration in men has a weak association with physical strength and functional outcomes through its associations with lean and fat mass. [source] African American women's beliefs about mental illness, stigma, and preferred coping behaviors,RESEARCH IN NURSING & HEALTH, Issue 5 2009Earlise C. Ward Abstract We examined African American women's representations/beliefs about mental illness, preferred coping behaviors if faced with mental illness, whether perceived stigma was associated with treatment-seeking, and if so, whether it was related to beliefs and coping preference, and whether these variables differed by age group. Participants were 185 community-dwelling African American women 25 to 85 years of age. Results indicated the women believed that mental illness is caused by several factors, including family-related stress and social stress due to racism, is cyclical, and has serious consequences but can be controlled by treatment. Participants endorsed low perceptions of stigma. Major preferred coping strategies included praying and seeking medical and mental health care. Age differences were found in all variables except stigma. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:480,492, 2009 [source] Annotation: Children's relationships with their nonresident fathersTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 4 2004Judy Dunn Background:, The frequency of parental separation means that increasing numbers of children have fathers who live in different households from mother-and-child; the significance of contact and relationships between children and their nonresident fathers for children's adjustment is receiving growing attention. Lessons from this research are considered. Methods:, Recent meta-analyses and overviews of research, and key research projects, are discussed. Findings related to contact and relationship quality are the main focus of the annotation. Results:, Economic support from nonresident fathers is related to children's well-being, and continues to be a key factor. Findings on contact are more mixed, especially from early studies; the effect size of associations between contact and positive child outcome has increased in recent research. Quality of child,father relationships is consistently related to adjustment outcome. Authoritative parenting, involvement and feelings of closeness are of particular importance in relation to adjustment, and these links are related to the quality of mother,nonresident father relations, and the mother,child relationship. Age differences, patterns over time, and gender are discussed; the perspectives of fathers and the problems they face in maintaining authoritative relationships are considered. Conclusions:, The significance of child,nonresident father relationships for children's and fathers' well-being is clear and merits further research; fruitful new directions for such research, within the framework of other family relationships, are outlined. [source] Age differences in learning from text: Evidence for functionally distinct text processing systemsAPPLIED COGNITIVE PSYCHOLOGY, Issue 4 2009Matthew C. Shake We investigated the influence of sentence elaboration on self-regulated learning in order to examine age differences in resource allocation to the construction of textbase- and discourse-level representations. Older and younger adults learned about a topic by reading a series of sentences varying in elaboration (from simple factoids to highly elaborated text) and manner of presentation (progressive change in elaboration vs. random change in elaboration). Younger readers were more likely to recall information from factoids; older adults, from highly elaborated text. Relative to young, older readers showed an advantage in the progressive presentation condition, which minimised frequent changes between textbase- and discourse-level processing. Older adults showed poorer memory monitoring for factoids and less elaborated discourse relative to young, but when passages were highly elaborated or presented progressively, age differences were eliminated. Results support the idea that textbase- and discourse-level encoding arise from functionally distinct systems whose regulation depends on text properties and reader age. Copyright © 2008 John Wiley & Sons, Ltd. [source] The effect of a prior cognitive interview on children's acceptance of misinformationAPPLIED COGNITIVE PSYCHOLOGY, Issue 4 2003Robyn E. Holliday This research examined whether a Cognitive interview facilitates correct recall in children aged 4 to 5 and 9 to 10 years, and whether a Cognitive interview given before post-event misinformation reduces children's reporting of suggestions on subsequent memory tests. Children were presented with an event followed the next day by a Cognitive or a Memorandum interview. Children were then read a post-event summary containing misleading suggestions. The next day all children were given both standard test and modified forced-choice cued-recall tests. The free recall phase of the Cognitive interview elicited the greatest number of correct details. Age differences were found such that 9- to 10-year-old children's reports were more accurate and more complete than those of the 4- to 5-year-olds. More correct person, action and object details were reported in a Cognitive interview. Misinformation effects were found in both age groups on the standard test whereas on the modified test such an effect was only found in the 4- to 5-year-olds. Children's reporting of suggestions was unaffected by prior interview. Copyright © 2003 John Wiley & Sons, Ltd. [source] Age differences in fall-related injury hospitalisations and trauma presentationsAUSTRALASIAN JOURNAL ON AGEING, Issue 3 2010Rebecca Mitchell Aim:, To examine fall-related hospitalised morbidity in New South Wales (NSW) and to describe the pattern of fall-related major trauma presentations at a Level 1 Trauma Centre in NSW for younger and older fallers. Methods:, Fall-related injuries were identified in the NSW Admitted Patients Data Collection during 1 July 1999,30 June 2008 and the trauma registry of the NSW St George Public Hospital during 1 January 2006,6 December 2008. Results:, There were 434 138 hospitalisations and 862 fall-related trauma presentations. Older fallers had a higher incidence of hospitalisation, being more likely to fall on the same level during general activities at home, injuring their hip or thigh. Older fallers were also more likely to have an Injury Severity Score > 9, undergo physiotherapy and stay in hospital for >1 day than younger fallers. Conclusion:, Falls, particularly for older individuals, are an important cause of serious injury, representing a considerable burden in terms of hospitalised morbidity. [source] Age differences in dual information-processing modes,,§CANCER, Issue S12 2008Implications for cancer decision making Abstract Age differences in affective/experiential and deliberative processes have important theoretical implications for cancer decision making, as cancer is often a disease of older adulthood. The authors examined evidence for adult age differences in affective and deliberative information processes, reviewed the sparse evidence about age differences in decision making, and introduced how dual process theories and their findings might be applied to cancer decision making. Age-related declines in the efficiency of deliberative processes predict poorer-quality decisions as we age, particularly when decisions are unfamiliar and the information is numeric. However, age-related adaptive processes, including an increased focus on emotional goals and greater experience, can influence decision making and potentially offset age-related declines. A better understanding of the mechanisms that underlie cancer decision processes in our aging population should ultimately allow us to help older adults to better help themselves. Cancer 2008;113(12 suppl):3556,67. © 2008 American Cancer Society. [source] The Head Bone's Connected to the Neck Bone: When Do Toddlers Represent Their Own Body Topography?CHILD DEVELOPMENT, Issue 3 2010Celia A. Brownell Developments in very young children's topographic representations of their own bodies were examined. Sixty-one 20- and 30-month-old children were administered tasks that indexed the ability to locate specific body parts on oneself and knowledge of how one's body parts are spatially organized, as well as body-size knowledge and self-awareness. Age differences in performance emerged for every task. Body-part localization and body spatial configuration knowledge were associated; however, body topography knowledge was not associated with body-size knowledge. Both were related to traditional measures of self-awareness, mediated by their common associations with age. It is concluded that children possess an explicit, if rudimentary, topographic representation of their own body's shape, structure, and size by 30 months of age. [source] Motivated Scientific Reasoning Biases, Epistemological Beliefs, and Theory Polarization: A Two-Process Approach to Adolescent CognitionCHILD DEVELOPMENT, Issue 5 2000Paul A. Klaczynski Theory-motivated reasoning biases arise when different reasoning skills are invoked to evaluate evidence that is congruent or incongruent with individuals' belief systems. To explore this phenomenon, 66 early and 73 middle adolescents evaluated evidence relevant to their theories of social class or religion. In both conditions, reasoning biases were found, but in-group biases were evident only in the religion condition. In both conditions, higher order scientific reasoning was used to reject theory-incongruent evidence and judgmental heuristics (i.e., cognitive rules of thumb) were used to evaluate theory-congruent evidence. In both conditions, subsequent to the evidence presentation, adolescents' theories became more extreme (i.e., polarized) than at the outset of the experiment. Beliefs regarding the origin, acquisition, and certainty of knowledge, however, appeared to moderate reasoning biases and theory polarization. Age differences emerged on only one index of bias: In the religion condition, middle adolescents were more likely to treat theory-incongruent evidence as implausible. These findings are pertinent to theories of cognitive development, decision making, rationality, and in-group favoritism. [source] Factors affecting the reproductive biology of Melittobia digitata and failure to meet the sex ratio predictions of Hamilton's local mate competition theoryENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2003M.F. Cooperband Abstract Melittobia digitata Dahms (Eulophidae, Tetrastichini), a species of parasitic wasp satisfying all of Hamilton's local mate competition requisites, does not exhibit the predicted change in sex ratio with increased foundress number. A multifactorial design was used to test how age, oviposition experience, feeding experience, mating, and foundress number affect host-acceptance, number of offspring, and sex ratio of this species developing on honey bee pupae, Apis mellifera (L.) (Apidae, Apini). All factors significantly affected the time it took for oviposition to commence. Females oviposited soonest when they were 2 days old, mated, had previous feeding and oviposition experience, and were placed on hosts with multiple foundresses. Although the age difference between 2- and 5-day-old females is small, it significantly affected reproductive behavior. Age, mating, and foundress number were found to have an effect on sex ratio, however, the foundress effect was found to be a mathematical artifact of the limited host size. After correcting for this variable, females were found to have a constant sex ratio of approximately 0.05. Several 2-way interactions between factors were revealed: age and experience, age and foundress number, age and mating, foundress number and experience, and foundress number and mating. One 3-way interaction was found between age, mating, and foundress number. This study demonstrates that the sex ratio of M. digitata is not altered with increased foundresses, as predicted by Hamilton, and that slight changes in preconditioning may modify reproductive behavior. [source] Components of Relationship Quality in ChimpanzeesETHOLOGY, Issue 9 2008Orlaith N. Fraser A novel approach to studying social relationships in captive adult chimpanzees (Pan troglodytes) was taken by using principal components analysis (PCA) to extract three key components of relationship quality from nine behavioural variables. Based on the loadings of the behavioural variables, the components appeared to match previously hypothesized critical aspects of social relationships and were therefore labelled Value, Compatibility and Security. The effects of kinship, sex combination, age difference and time spent together on each of the relationship quality components were analysed. As expected, kin were found to have more valuable, compatible and secure relationships than non-kin. Female,female dyads were found to be more compatible than male,male or mixed-sex dyads, whereas the latter were found to be most secure. Partners of a similar age were found to have more secure and more valuable relationships than those with a larger age gap. Individuals that were together in the group for longer were more valuable and more compatible, but their relationships were found to be less secure than individuals that were together in the group for a shorter time. Although some of the results may be unexpected based on chimpanzee socio-ecology, they fit well overall with the history and social dynamics of the study group. The methods used confer a significant advantage in producing quantitative composite measures of each component of relationship quality, obtained in an objective manner. These findings therefore promote the use of such measures in future studies requiring an assessment of the qualities of dyadic social relationships. [source] The development of attention and response inhibition in early childhoodINFANT AND CHILD DEVELOPMENT, Issue 5 2008Jami Bartgis Abstract The goal of this study was to examine the development of attention and response inhibition from ages 5 to 7. Forty children (20 5-year-olds and 20 7-year-olds) completed four counterbalanced phases of a continuous performance task. Phase 1 was designed to measure attention without distraction, Phase 2 was designed to measure attention with distraction, Phase 3 was designed to measure attention and response inhibition without distraction, and Phase 4 was designed to measure attention and response inhibition with distraction. With regard to attention, 7-year-olds performed significantly better than 5-year-olds. This age difference was more pronounced when distraction was present. With regard to response inhibition, there were no significant age differences. These results appear to suggest that attention improves between ages 5 and 7 but response inhibition does not. However, conclusions regarding response inhibition were limited because the distraction appeared to have had too powerful an effect on the 5-year-olds. Implications and future directions are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] A comparative, cross-national analysis of partner-killing by women in cohabiting and marital relationships in Australia and the United StatesAGGRESSIVE BEHAVIOR, Issue 3 2004Jenny Mouzos Abstract Using a national-level United States database, T. K. Shackelford [Partner-killing by women in cohabiting relationships and marital relationships. Homicide Studies 5: 253-266, 2001] calculated rates of partner-killing by women by relationship type (cohabiting or marital), by partner ages, and by the age difference between partners. Men in cohabiting relationships were 10 times more likely to be killed by their partners than were married men. Within marriages, the risk of being killed by a partner decreased with a man's age. Within cohabiting relationships, in contrast, middle-aged men were at greatest risk of being killed by their partners. The risk that a man will be killed by his partner generally increased with greater age difference between partners. We sought to replicate the findings of Shackelford [2001] using national-level data held as part of the National Homicide Monitoring Program (NHMP) at the Australian Institute of Criminology in Australia. The NHMP holds data on over 3,500 homicides that occurred in Australia between 1989 and 2000. Despite the higher rate of partner-killing in the United States, and despite other cultural differences between the two countries (for example, the prominent gun culture in the United States), we replicated the key patterns with the Australian data. Aggr. Behav. 30:206,216, 2004. © 2004 Wiley-Liss, Inc. [source] Recipient and donor factors influence the incidence of graft-vs.-host disease in liver transplant patientsLIVER TRANSPLANTATION, Issue 4 2007Edie Y. Chan Acute cellular graft-vs.-host disease (GVHD) following liver transplantation has an incidence of 1 to 2% and a mortality rate of 85%. Our aim was to identify a patient population at high risk for developing GVHD using a large clinical database to study both recipient and donor factors. We compared our liver transplant patients who developed GVHD to those that did not for recipient and donor factors and combinations of factors. For 2003,2004 we had 205 first-time liver transplant patients surviving >30 days. From this group, 4 (1.9%) developed GVHD. Compared to the control group, there were no significant differences in recipient age, recipient gender, donor age, donor gender, total ischemia time, donor-recipient human leukocyte antigen (HLA) mismatch, or donor-recipient age difference. Percentages of liver disease etiologies among the patients who developed GVHD were as follows: 16% (1/6) autoimmune hepatitis (AIH) (P = 0.003), 5.6% (3/54) alcoholic liver disease (ALD) (P = 0.057), and 7.1% (3/42) hepatocellular carcinoma (HCC) (P = 0.026). The incidence of GVHD in patients with glucose intolerance (either Type I or Type II diabetes mellitus [DM]) was significant (P = 0.022). Focusing on patients only with high-risk factors for GVHD during the years 2003,2005, we had 19 such patients. Four of these high-risk patients developed GVHD. Three of these 4 patients had received a donor liver with steatosis of degree ,mild compared to only 2 of the 15 high-risk patients who did not develop GVHD (P = 0.037). In conclusion, we have identified liver transplant patients with AIH or the combination of ALD, HCC, and glucose intolerance who receive a steatotic donor liver as being at high risk for developing GVHD. Liver Transpl 13:516,522, 2007. © 2007 AASLD. [source] Recurrent wheezing after respiratory syncytial virus or non-respiratory syncytial virus bronchiolitis in infancy: a 3-year follow-upALLERGY, Issue 9 2009H. Valkonen Background:, Recent studies have suggested that rhinovirus-associated early wheezing is a greater risk factor for development of recurrent wheezing in children than is early wheezing associated with respiratory syncytial virus (RSV). We determined the development of recurrent wheezing in young children within 3 years after hospitalization for RSV or non-RSV bronchiolitis. Methods:, We identified retrospectively all children <2 years of age who were admitted to Turku University Hospital because of bronchiolitis in the months of August,December during 1988,2001. The primary outcome was recurrent wheezing that required long-term asthma medication. Data on asthma medications of the individual children were derived from the Social Insurance Institution of Finland. Results:, Within the first year after hospitalization, 36 of 217 (16.6%) children with non-RSV bronchiolitis developed recurrent wheezing, compared with five of 199 (2.5%) children with RSV bronchiolitis [relative risk (RR) 6.6; 95% confidence interval (CI) 2.6,16.5]. The rates of recurrent wheezing were significantly increased in the non-RSV group also within 2 years (RR 2.9; 95% CI 1.7,5.1) and 3 years (RR 3.4; 95% CI 2.0,5.7) after hospitalization. The increased risk of recurrent wheezing in children with non-RSV-associated bronchiolitis was observed both in boys and girls at all time points of the 3-year follow-up, and it was not explained by the age difference between the RSV and non-RSV groups or any confounding seasonal factors. Conclusion:, Children hospitalized with bronchiolitis caused by other viruses than RSV develop recurrent wheezing at substantially higher rates during a 3-year follow-up period than do children with RSV-induced bronchiolitis. [source] 39Ar- 40Ar chronology of R chondritesMETEORITICS & PLANETARY SCIENCE, Issue 3 2003Eleanor T. DIXON The 39Ar- 40Ar ages were determined on whole-rock samples of four R chondrites: Carlisle Lakes, Rumuruti, Acfer 217, and Pecora Escarpment #91002 (PCA 91002). All samples are breccias except for Carlisle Lakes. The age spectra are complicated by recoil and diffusive loss to various extents. The peak 39Ar- 40Ar ages of the four chondrites are 4.35, ,4.47 ± 0.02, 4.30 ± 0.07 Ga, and 4.37 Ga, respectively. These ages are similar to Ar-Ar ages of relatively unshocked ordinary chondrites (4.52,4.38 Ga) and are older than Ar-Ar ages of most shocked ordinary chondrites («4.2 Ga). Because the meteorites with the oldest (Rumuruti, ,4.47 Ga) and the youngest (Acfer 217, ,4.30 Ga) ages are both breccias, these ages probably do not record slow cooling within an undisrupted asteroidal parent body. Instead, the process of breccia formation may have differentially reset the ages of the constituent material, or the differences in their age spectra may arise from mixtures of material that had different ages. Two end-member type situations may be envisioned to explain the age range observed in the R chondrites. The first is if the impact(s) that reset the ages of Acfer 217 and Rumuruti was very early. In this case, the ,170 Ma maximum age difference between these meteorites may have been produced by much deeper burial of Acfer 217 than Rumuruti within an impact-induced thick regolith layer, or within a rubble pile type parent body following parent body re-assembly. The second, preferred scenario is if the impact that reset the age of Acfer 217 was much later than that which reset Rumuruti, then Acfer 217 may have cooled more rapidly within a much thinner regolith layer. In either scenario, the oldest age obtained here, from Rumuruti, provides evidence for relatively early (,4.47 Ga) impact events and breccia formation on the R chondrite parent body. [source] PG 1258+593 and its common proper motion magnetic white dwarf counterpartMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2010J. Girven ABSTRACT We confirm SDSS J130033.48+590407.0 as a common proper motion companion to the well-studied hydrogen-atmosphere (DA) white dwarf PG 1258+593 (GD322). The system lies at a distance of 68 ± 3 pc, where the angular separation of 16.1 ± 0.1 arcsec corresponds to a minimum binary separation of 1091 ± 7 au. SDSS J1300+5904 is a cool (Teff= 6300 ± 300 K) magnetic white dwarf (B, 6 mG). PG 1258+593 is a DA white dwarf with Teff= 14790 ± 77 K and log g= 7.87 ± 0.02. Using the white dwarf mass,radius relation implies the masses of SDSS J1300+5904 and PG 1258+593 are 0.54 ± 0.06 and 0.54 ± 0.01 M,, respectively, and therefore a cooling age difference of 1.67 ± 0.05 Gyr. Adopting main-sequence lifetimes from stellar models, we derive an upper limit of 2.2 M, for the mass of the progenitor of PG 1258+593. A plausible range of initial masses is 1.4,1.8 M, for PG 1258+593 and 2,3 M, for SDSS J1300+5904. Our analysis shows that white dwarf common proper motion binaries can potentially constrain the white dwarf initial mass,final mass relation and the formation mechanism for magnetic white dwarfs. The magnetic field of SDSS J1300+5904 is consistent with an Ap progenitor star. A common envelope origin of the system cannot be excluded, but requires a triple system as progenitor. [source] Racial disparities in age at time of cardiovascular events and cardiovascular-related death in patients with systemic lupus erythematosusARTHRITIS & RHEUMATISM, Issue 9 2010Lisabeth V. Scalzi Objective To determine whether racial disparities exist with regard to the age at which patients with systemic lupus erythematosus (SLE) experience cardiovascular disease (CVD) and CVD-associated death. Methods Using the 2003,2006 Nationwide Inpatient Sample, we calculated the age difference between patients with SLE and their race- and sex-matched controls at the time of hospitalization for a cardiovascular event and for CVD-associated death. In addition, we calculated the age difference between white patients with SLE and sex-matched controls for each minority group for the same outcomes. Results The mean age difference between women with and those without SLE at the time of admission for a CVD event was 10.5 years. All age differences between women with SLE (n = 3,627) and women without SLE admitted for CVD were significant (P < 0.0001). Among different racial groups with SLE, black women were the youngest to be admitted with CVD (53.9 years) and to have a CVD-associated in-hospital death (52.8 years; n = 218). Black women with SLE were 19.8 years younger than race- and sex-matched controls at the time of CVD-associated death. Admission trends for CVD were reversed for black women, such that the highest proportions of these patients were admitted before age 55 years, and then the proportions steadily decreased across age categories. Among the 805 men with SLE who were admitted with a CVD event, those who were black or Hispanic were youngest. Conclusion There are significant racial disparities with regard to age at the time of hospital admission for CVD events and CVD-related hospitalization resulting in death in patients with SLE. [source] Sibling Differentiation in Adolescence: Implications for Behavioral Genetic TheoryCHILD DEVELOPMENT, Issue 6 2000Mark E. Feinberg The presence of sibling "differentiating rocesses", defined as processes in which increased sibling similarity in environmental or genetic factors leads to differences in sibling outcomes , poses a challenge for standard behavioral genetic theory and research. The presence of differentiation processes may affect estimates of genetic and environmental parameters in ways that have not been fully recognized. Utilizing data from the Nonshared Environment and Adolescent Development project, this study examined whether differentiating processes existed for seven composite indices of positive and negative adolescent adjustment. The 720 sibling pairs in the study were broken down into groups by age difference (0 , 4 years) between siblings. The hypothesis that siblings close in age would demonstrate lower correlations on adjustment measures was generally supported at two time points, three years apart. However, siblings one year apart at Time 1 were more similar to each other than were siblings two years apart, suggesting that shared environmental influences counteract sibling differentiation processes for these siblings. The overall trend supporting sibling differentiation was found to be unrelated to measures of sibling positivity and negativity. [source] A dual systems model of adolescent risk-taking,DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2010Laurence Steinberg Abstract It has been hypothesized that reward-seeking and impulsivity develop along different timetables and have different neural underpinnings, and that the difference in their timetables helps account for heightened risk-taking during adolescence. In order to test these propositions, age differences in reward-seeking and impulsivity were examined in a socioeconomically and ethnically diverse sample of 935 individuals between the ages of 10 and 30, using self-report and behavioral measures of each construct. Consistent with predictions, age differences in reward-seeking follow a curvilinear pattern, increasing between preadolescence and mid-adolescence, and declining thereafter. In contrast, age differences in impulsivity follow a linear pattern, with impulsivity declining steadily from age 10 on. Heightened vulnerability to risk-taking in middle adolescence may be due to the combination of relatively higher inclinations to seek rewards and still maturing capacities for self-control. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 216,224, 2010 [source] Changes in hyporesponsiveness to acute amphetamine and age differences in tyrosine hydroxylase immunoreactivity in the brain over adolescence in male and female ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 5 2009Iva Z. Mathews Abstract We investigated hyposensitivity after amphetamine in early (postnatal Day 30; P30) and late (P45) adolescent rats compared to adults (P70) in experiment 1. Locomotor activity was measured for 1,hr after the first (acute) and second (24,hr later) injection of amphetamine (0.5 or 1.5,mg/kg). P30 and P45 rats were transiently hypoactive compared to adults, as indicated by reduced locomotor activity after acute amphetamine and enhanced activity after the second injection in adolescents only. In experiment 2, ovariectomy did not alter locomotor activity during habituation at any age compared to intact rats, and, as for intact adolescents, ovariectomized adolescents continued to be less active after amphetamine than adults, suggesting gonadal immaturity alone cannot account for age differences in experiment 1. However, ovariectomy attenuated the increase in activity after the second treatment. In experiment 3 involving untreated rats, tyrosine hydroxylase immunoreactivity was reduced in P30, P40, and P50 compared to P90 rats in the nucleus accumbens core and the medial prefrontal cortex. Thus, adolescents may have an increased threshold of behavioral activation that can be overcome with either a higher dose or with repeated amphetamine treatment, and may be related to changes in the dopamine system over development. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 417,428, 2009. [source] | ||||||||||||||||||||||||||||||||||||||||||||||