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1.
Kubarych TS Prom-Wormley EC Franz CE Panizzon MS Dale AM Fischl B Eyler LT Fennema-Notestine C Grant MD Hauger RL Hellhammer DH Jak AJ Jernigan TL Lupien SJ Lyons MJ Mendoza SP Neale MC Seidman LJ Tsuang MT Kremen WS 《Genes, Brain & Behavior》2012,11(5):539-544
Self-esteem and well-being are important for successful aging, and some evidence suggests that self-esteem and well-being are associated with hippocampal volume, cognition and stress responsivity. Whereas most of this evidence is based on studies on older adults, we investigated self-esteem, well-being and hippocampal volume in 474 male middle-aged twins. Self-esteem was significantly positively correlated with hippocampal volume (0.09, P = 0.03 for left hippocampus, 0.10, P = 0.04 for right). Correlations for well-being were not significant (Ps > 0.05). There were strong phenotypic correlations between self-esteem and well-being (0.72, P < 0.001) and between left and right hippocampal volume (0.72, P < 0.001). In multivariate genetic analyses, a two-factor additive genetic and unique environmental (AE) model with well-being and self-esteem on one factor and left and right hippocampal volumes on the other factor fits the data better than Cholesky, independent pathway or common pathway models. The correlation between the two genetic factors was 0.12 (P = 0.03); the correlation between the environmental factors was 0.09 (P > 0.05). Our results indicate that largely different genetic and environmental factors underlie self-esteem and well-being on one hand and hippocampal volume on the other. 相似文献
2.
Claudine Wulfman Sophie Tezenas du Montcel Pierre Jonas Jalal Fattouh Christophe Rignon‐Bret 《Gerodontology》2010,27(4):266-271
doi:10.1111/j.1741‐2358.2009.00331.x Aesthetic demand of French seniors: a large‐scale study Objectives: The needs of seniors for oral health and aesthetics are growing, as are their demands for aesthetics. This large‐scale study aims to identify the demand for aesthetics for a population aged over 55, and the influence of age and gender. Methods: A 15‐item questionnaire was placed on the web in partnership with a major magazine dedicated to seniors. It reflected practitioners’ questions with regard to senior patient expectations: aesthetic demand assessment, most commonly expressed complaints, the importance given to tooth colour, knowledge of available therapeutic treatments and motivation levels for treatment. Results: The survey generated 3868 responses, 61% from women; 77% of respondents declared being satisfied to very satisfied with their smile. Their highest priority to improve their smile was tooth alignment, followed by their shape, length and shade. Although 60% of respondents were satisfied with their current shading, 53% would prefer to have them whitened. Aesthetic treatments were well‐known to seniors. Over four‐fifths of them had heard of dental implants and ceramic crowns. Two‐thirds of those who wished to improve their smile were considering dental treatment. Conclusion: The high number of collected questionnaires confirms the strong interest shown by seniors for dental aesthetics, particularly from women. Baby‐boomers seem more attentive to the appearance of their smile than their elders. However, the importance of appearance decreases with age, as it becomes less of a priority, with attention more focused on general health. 相似文献
3.
Lemmon CR Ludwig DA Howe CA Ferguson-Smith A Barbeau P 《Obesity (Silver Spring, Md.)》2007,15(3):695-703
Objective: The goal was to identify correlates of adherence to a structured physical activity (PA) program. Research Methods and Procedures: Subjects were 136 8‐ to 12‐year‐old African‐American girls. Potential correlates at baseline were: 1) fitness index (FI: % body fat from DXA and cardiovascular fitness from treadmill test), and 2) self‐esteem, anxiety, attitude to school and teachers, relationship with parents, and interpersonal relations (Behavioral Assessment System for Children). The 10‐month PA program included 80 minutes of PA offered 5 days/wk. Regression tree classification was used to model attendance. Results: Six splits occurred (34% total variance explained). Less anxious subjects attended more often than highly anxious subjects (3 days/wk vs. 1.5 days/wk) did. Subjects with a healthier FI attended more often than those with a less healthy FI (3 days/wk vs. 0.5 days/wk) did. Younger subjects attended more often than older ones (3 days/wk vs. 2.5 days/wk) did. The next two splits were again with anxiety (3.5 days/wk vs. 3 days/wk) and FI (3 days/wk vs. 2.5 days/wk). Finally, subjects with higher levels of self‐esteem attended more often than those with lower levels (3.5 days/wk vs. 2 days/wk) did. Discussion: Subjects who were self‐confident, younger, fitter, and less anxious were more likely to participate regularly. This suggests that children who may be more likely to benefit from a PA program are less likely to participate. To enhance participation in PA programs, especially in older African‐American girls: 1) psychological concerns should be identified and addressed before enrollment, and 2) programs should be designed to be appealing to children of all fitness levels. 相似文献
4.
Gary D. Foster Suzanne Phelan Thomas A. Wadden Debra Gill Jenna Ermold Elizabeth Didie 《Obesity (Silver Spring, Md.)》2004,12(8):1271-1277
Objective: This pilot study assessed the short‐ and long‐term effects of a modified cognitive behavioral treatment designed to facilitate obese patients’ acceptance of a 5% to 10% reduction in initial weight. Research Methods and Procedures: Participants were 17 women with a mean age of 46.5 ± 9.7 years and BMI of 34.7 ± 2.9 kg/m2. They participated in a 40‐week program that included four phases. The first discussed the benefits of modest weight losses and the potential adverse effects of unrealistic expectations. Phase II provided instruction in traditional cognitive behavioral methods of weight control Phase III focused on methods to improve body image and self‐esteem. Phase IV addressed skills for weight maintenance. Changes in weight, self‐esteem, body image, and quality of life were assessed at the end of treatment and 1 year later (week 92). Results: At week 40, participants lost an average of 5.7 ± 5.3% of initial weight, which was associated with significant improvements in body image, self‐esteem, and quality of life. Improvements in psychosocial status were maintained at week 92, although mean weight loss at this time had declined to 2.9 ± 5.6% of initial weight. Increased satisfaction with body weight at week 40 was associated with significantly better maintenance of weight loss at follow‐up (r = ?0.70; p = 0.02). Discussion: Having participants seek only modest initial weight losses does not appear to facilitate weight maintenance. However, increasing patients’ satisfaction with their body weight at the end of treatment may help improve weight maintenance. More research is needed on the relation between satisfaction with initial weight loss and long‐term success. 相似文献
5.
- Breeding systems of plants determine their reliance on pollinators and ability to produce seeds following self‐pollination. Self‐sterility, where ovules that are penetrated by self‐pollen tubes that do not develop into seeds, is usually considered to represent either a system of late‐acting self‐incompatibility or strong early inbreeding depression. Importantly, it can lead to impaired female function through ovule or seed discounting when stigmas receive mixtures of self and cross pollen, unless cross pollen is able to reach the ovary ahead of self pollen (‘prepotency’). Self‐sterility associated with ovule penetration by self‐pollen tubes appears to be widespread among the Amaryllidaceae.
- We tested for self‐sterility in three Cyrtanthus species – C. contractus, C. ventricosus and C. mackenii – by means of controlled hand‐pollination experiments. To determine the growth rates and frequency of ovule penetration by self‐ versus cross‐pollen tubes, we used fluorescence microscopy to examine flowers of C. contractus harvested 24, 48 and 72 h after pollination, in conjunction with a novel method of processing these images digitally. To test the potential for ovule discounting (loss of cross‐fertilisation opportunities when ovules are disabled by self‐pollination), we pollinated flowers of C. contractus and C. mackenii with mixtures of self‐ and cross pollen.
- We recorded full self‐sterility for C. contractus and C. ventricosus, and partial self‐sterility for C. mackenii. In C. contractus, we found no differences in the growth rates of self‐ and cross‐pollen tubes, nor in the proportions of ovules penetrated by self‐ and cross‐pollen tubes. In this species, seed set was depressed (relative to cross‐pollinated controls) when flowers received a mixture of self and cross pollen, but this was not the case for C. mackenii.
- These results reveal variation in breeding systems among Cyrtanthus species and highlight the potential for gender conflict in self‐sterile species in which ovules are penetrated and disabled by pollen tubes from self pollen.
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Abstract: The breeding system of Luehea grandiflora (Tiliaceae‐Malvaceae s.l.) was investigated using hand pollinations and fluorescence microscopy studies of pollen tube growth. Although selfed flowers persisted for some 10 days, our study indicates that L. grandiflora is self‐incompatible, with self pollen tube inhibition in the upper style, as occurs in many taxa with homomorphic, gametophytic self‐incompatibility (GSI). L. grandiflora is only the second species reported within the Malvales with homomorphic stylar inhibition. This result is discussed within the context of a report for self‐compatibility in this species, and we also consider the phylogenetic implications for the occurrence of GSI in the family Malvaceae s.l. 相似文献
7.
Sweet cherry is a self‐incompatible fruit tree species in the Rosaceae. As other species in the family, sweet cherry exhibits S‐RNase‐based gametophytic self‐incompatibility. This mechanism is genetically determined by the S‐locus that encodes the pollen and pistil determinants, SFB and S‐RNase, respectively. Several self‐compatible sweet cherry genotypes have been described and most of them have mutations at the S‐locus leading to self‐compatibility. However, ‘Cristobalina’ sweet cherry is self‐compatible due to a mutation in a pollen function modifier that is not linked to the S‐locus. To investigate the physiology of self‐compatibility in this cultivar, S‐locus segregation in crosses involving ‘Cristobalina’ pollen, and pollen tube growth in self‐ and cross‐pollinations, were studied. In the crosses with genotypes sharing only one S‐haplotype, the non‐self S‐haplotype was inherited more frequently than the self S‐haplotype. Pollen tube growth studies revealed that the time to travel the whole length of the style was longer for self‐pollen tubes than for cross‐pollen tubes. Together, these results suggest that ‘Cristobalina’ pollen tube growth is slower after self‐pollination than after cross‐pollination. This reproductive strategy would allow self‐fertilisation in the absence of compatible pollen but would promote cross‐fertilisation if cross‐compatible pollen is available, a possible case of cryptic self‐incompatibility. This bet‐hedging strategy might be advantageous for an ecotype that is native to the mountains of the Spanish Mediterranean coast, in the geographical limits of the distribution of this species. ‘Cristobalina’ blooming takes place very early in the season when mating possibilities are scarce and, consequently, self‐compatibility may be the only possibility for this genotype to produce offspring. 相似文献
8.
Objectives: Pediatricians underdiagnose overweight and feel ineffective at counseling. Given the relationship between physicians’ health and health habits and counseling behaviors, we sought to determine the 1) percentage of pediatricians who are overweight; 2) accuracy of pediatricians’ own weight status classification; and 3) relationship between weight self‐perception and perceived ease of obesity counseling. Research Methods and Procedures: This study was a cross‐sectional, mail survey of North Carolina pediatricians that queried about their weight status and ease of counseling. Accuracy of pediatricians’ self‐classification of weight status was compared with BMIs derived from self‐reported height and weight. Using logistic regression, controlling for potential confounding variables, we examined the association between weight perception and ease of counseling. Results: The unadjusted response rate was 62%, and the adjusted response rate was 71% (n = 355). Nearly one‐half (49%) of overweight pediatricians did not identify themselves as such. Men had greater adjusted odds of misclassifying overweight than women [odds ratio (OR), 3.61; 95% confidence interval (CI) = 1.81, 7.21]. Self‐classified “thin” pediatricians had nearly six times the odds of reporting more counseling difficulty as a result of their weight than “average” weight pediatricians (OR = 5.69; 95% CI = 2.30, 14.1), and self‐identified “overweight” pediatricians reported nearly four times as great counseling difficulty as “average” weight physicians (OR = 3.84; 95% CI = 1.11, 13.3), after adjustment for self‐reported BMI weight status and other potential confounders. Discussion: The roles that physician weight misclassification and self‐perception potentially play in influencing rates of obesity counseling warrant further research. 相似文献
9.
Puurtinen M Emily Knott K Suonpää S Nissinen K Kaitala V 《Journal of evolutionary biology》2007,20(3):901-912
We have quantified the natural mating system in eight populations of the simultaneously hermaphroditic aquatic snail Lymnaea stagnalis, and studied the ecological and genetic forces that may be directing mating system evolution in this species. We investigated whether the natural mating system can be explained by the availability of mates, by the differential survival of self- and cross-fertilized snails in nature, and by the effects of mating system on parental fecundity and early survival. The natural mating system of L. stagnalis was found to be predominantly cross-fertilizing. Density of snails in the populations had no relationship with the mating system, suggesting that outcrossing rates are not limited by mate availability at the population densities observed. Contrary to expectations for outcrossing species, we detected no evidence for inbreeding depression in survival in nature with inferential population genetic methods. Further, experimental manipulations of mating system in the laboratory revealed that self-fertilization had no effect on parental fecundity, and only minor effects on offspring survival. Predominance of cross-fertilization despite low apparent fitness costs of self-fertilization is at odds with the paradigm that high self-fertilization depression is necessary for maintenance of cross-fertilization in self-compatible hermaphrodites. 相似文献
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11.
David A. Langs Robert H. Blessing Dongyao Guo 《Acta Crystallographica. Section D, Structural Biology》2001,57(9):1351-1353
A procedure was recently described that used the correlation coefficient (CC) agreement between the observed |F h | and their associated unbiased `omit map' extrapolated values |X h | from an initial trial map as the basis for resolving the SIR or SAS phase ambiguity. It is noted here that a significant improvement in selectivity can be obtained if this agreement is expressed in terms of the complex‐valued F h and X h . A new scheme is outlined to exploit the weighted average of the two SIR or SAS phase choices. This procedure requires six FFTs per phase compared with three for the older method that randomly selected either of the two permitted phase choices from the Argand diagram as starting values. Trial calculations are encouraging for applications as low as 4 Å resolution. 相似文献
12.
David A. Turner Peter Baillie‐Johnson Alfonso Martinez Arias 《BioEssays : news and reviews in molecular, cellular and developmental biology》2016,38(2):181-191
Understanding the mechanisms of early embryonic patterning and the timely allocation of specific cells to embryonic regions and fates as well as their development into tissues and organs, is a fundamental problem in Developmental Biology. The classical explanation for this process had been built around the notion of positional information. Accordingly the programmed appearance of sources of Morphogens at localized positions within a field of cells directs their differentiation. Recently, the development of organs and tissues from unpatterned and initially identical stem cells (adult and embryonic) has challenged the need for positional information and even the integrity of the embryo, for pattern formation. Here we review the emerging area of organoid biology from the perspective of Developmental Biology. We argue that the events underlying the development of these systems are not purely linked to “self‐organization,” as often suggested, but rather to a process of genetically encoded self‐assembly where genetic programs encode and control the emergence of biological structures. 相似文献
13.
The assessment of age‐at‐death in non‐adult skeletal remains is under constant review. However, in many past societies an individual's physical maturation may have been more important in social terms than their exact age, particularly during the period of adolescence. In a recent article (Shapland and Lewis: Am J Phys Anthropol 151 (2013) 302–310) highlighted a set of dental and skeletal indicators that may be useful in mapping the progress of the pubertal growth spurt. This article presents a further skeletal indicator of adolescent development commonly used by modern clinicians: cervical vertebrae maturation (CVM). This method is applied to a collection of 594 adolescents from the medieval cemetery of St. Mary Spital, London. Analysis reveals a potential delay in ages of attainment of the later CVM stages compared with modern adolescents, presumably reflecting negative environmental conditions for growth and development. The data gathered on CVM is compared to other skeletal indicators of pubertal maturity and long bone growth from this site to ascertain the usefulness of this method on archaeological collections. Am J Phys Anthropol 153:144–153, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
14.
Kathleen Fuller 《American journal of physical anthropology》1998,106(3):323-328
Previous research (Tague [1994] Am. J. Phys. Anthropol. 95:27–40) has shown an age effect in pubic bone length among adult women. Tague found that in three prehistoric Native American skeletal samples, women aged 18–24 had a significantly shorter linea terminalis than did women aged 25 and older. The purpose of this research is to determine whether such a difference can be discerned in other female skeletal samples. Three female skeletal samples were used in this analysis: 75 African-American and 42 European-American females aged 18–39 from the Hamann-Todd Collection (collected between 1893 and 1938; Iscan, 1990) and 99 African-American females aged 18–39 from the Terry Collection (collected between 1914 and 1965; Cobb, 1933; Iscan, 1990). Several chord measurements of pubic bone length along the linea terminalis were analyzed by one-tailed t-tests of the separate samples subdivided into two age groups: 18–24 and 25–39 years. Of 15 comparisons between age groups, none differed significantly by age group within each sample. It is concluded that the observed significant difference in pubic bone length in the Native American female skeletal samples cannot be replicated in other samples and that there is no age effect on pubic bone length in the samples tested in this analysis. Tague's findings reflect either the occurrence of late menarche in prehistoric populations or differential survivorship. Am J Phys Anthropol 106:323–328, 1998. © 1998 Wiley-Liss, Inc. 相似文献
15.
Towne B Czerwinski SA Demerath EW Blangero J Roche AF Siervogel RM 《American journal of physical anthropology》2005,128(1):210-219
Menarche is the hallmark maturational event of female childhood. Many studies indicated a significant genetic contribution to the timing of the onset of menstruation, but most of these studies were limited by the use of retrospective data and by the use of data from only certain types of relatives (i.e., mothers and daughters, sisters, or twin sisters). The primary goal of this study was to use a modern maximum likelihood quantitative genetic method to estimate the heritability (h(2)) of age at menarche, using familial data collected over the course of the 74-year-old Fels Longitudinal Study. The secondary goal was to review earlier studies of the heritability of age at menarche. The study of the heritability of age at menarche presented here is unique for two reasons. First, because of the Fels Longitudinal Study's serial design, age-at-menarche data were collected prospectively from most participants. Second, because the Fels Longitudinal Study is a family study that has been conducted for decades, age-at-menarche data are available from many types of female relatives spanning multiple households and generations. The best-fitting and most parsimonious quantitative genetic model included provision for a secular decrease in age at menarche, and estimated the h(2) of age at menarche to be 0.49+/- 0.13 (95% confidence interval of h(2),=0.24-0.73). The results of this study are in general agreement with the findings of most previous studies of genetic influences on age at menarche, and suggest that it is reasonable to consider it well-established that approximately half the phenotypic variation among girls from developed nations in the timing of menarche is due to genetic factors. 相似文献
16.
Klervia Jaouen Estelle Herrscher Vincent Balter 《American journal of physical anthropology》2017,162(3):491-500
17.
《Addiction biology》2017,22(6):1665-1681
Alcohol is consumed orally by humans, and oral self‐administration has been successfully modeled in laboratory animals. Over the last several years, attempts have been made to develop a procedure for the reliable intravenous (IV) self‐administration of alcohol in rodents. IV self‐administration would provide a better tool for investigating neurobiological mechanisms of alcohol reinforcement and dependence because confounding factors associated with oral self‐administration, such as variations in orosensory sensitivity to alcohol and/or its absorption, are avoided. A review of the literature shows that rats, mice and non‐human primates can initiate and maintain IV self‐administration of alcohol. However, there are 50‐ to 100‐fold interspecies differences in the reported alcohol infusion doses required. Most surprising is that the infusion dose (1–2 mg/kg) that reliably maintains IV alcohol self‐administration in rats results in total alcohol intakes of only 20–25 mg/kg/hour, which are unlikely to have significant pharmacological effects. The evidence to support IV self‐administration of such low doses of alcohol in rats as well as the potential biological mechanisms underlying such self‐administration are discussed. The minute amounts of alcohol shown to reliably maintain IV self‐administration behavior in rats challenge the relationship between their blood alcohol levels and the rewarding and reinforcing effects of alcohol. 相似文献
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HUIQUAN BI 《Austral ecology》2004,29(4):408-417
Abstract The classic experiment that gave rise to the self‐thinning rule 40 years ago was re‐analysed using stochastic frontier functions. The estimated slope of the self‐thinning boundary line was almost identical to the original proposed value. However, contrary to the original conclusion that the self‐thinning boundary line remained invariant across the soil fertility gradient, the intercept was found to increase with soil fertility. Stochastic frontier analysis also provided a more realistic estimate of the maximum asymptotic stand density than the original work, by separating the effects of density‐dependent and density‐independent mortalities during self‐thinning in a composed error term in the model specification. The time‐course of self‐thinning across the soil fertility gradient was described by a non‐linear function, which enabled the estimation of a minimum possible stand density that could still maintain full site occupancy (i.e. the maximum asymptotic stand density at the end of self‐thinning). The maximum asymptotic stand density decreased more rapidly on more fertile soils and the difference in maximum asymptotic stand density among the five levels of soil fertility increased non‐linearly with time. Site carrying capacity was defined as stand biomass shown by the point on the self‐thinning boundary line at the end of self‐thinning. This definition led to a direct functional link between the self‐thinning boundary line and site carrying capacity for even‐aged plant populations. 相似文献
20.
G.‐L. Chen M. A. Novak J. S. Meyer B. J. Kelly E. J. Vallender G. M. Miller 《Genes, Brain & Behavior》2010,9(3):335-347
Tryptophan hydroxylase‐2 (TPH2) synthesizes neuronal serotonin and is linked to numerous behavioral traits. We have previously characterized the functionality of polymorphisms (especially 2051A>C) in 3’‐untranslated region (3’‐UTR) of rhesus monkey TPH2 (rhTPH2). This study further assessed the functionality of additional polymorphisms (–1605T>C, –1491Tn, –1485(AT)n, –1454A>G, –1325In>Del and –363T>G) in rhTPH2 5’‐flanking region (5’‐FR), and evaluated the effects of rhTPH2 5’ and 3’ genotypes on central serotonin turnover, hypothalamic–pituitary–adrenal (HPA) axis function and self‐injurious behavior (SIB) in 32 unrelated adult male monkeys of Indian origin. Haplotypes of the rhTPH2 5’‐FR polymorphisms exert a significant, cell‐dependent effect on reporter gene expression, primarily conferred by –1485(AT)n. The –1485(AT)n and 2051A>C polymorphisms interact to influence cerebrospinal fluid (CSF) 5‐HIAA and plasma adrenocorticotropic hormone (ACTH) in the afternoon. While –1485(AT)n exerts significant main effects on the afternoon cortisol level and nocturnal HPA negative feedback, 2051A>C has significant main effects on the morning cortisol level and cortisol response to ACTH challenge, as well as marginally significant main effects on the daytime HPA negative feedback and self‐biting rate. In addition, the genotype/allele frequency of the 5’‐FR –1325Ins>Del differed significantly between the self‐wounders and non‐wounders, whereas 3’‐UTR 2128S>L polymorphism differed significantly in genotype/allele frequency between the high‐ and low‐frequency biters. This study shows the functionality of rhTPH2 5’‐FR polymorphisms, and provides evidence for the differential association of rhTPH2 5’‐FR and 3’‐UTR polymorphisms with HPA axis function and SIB. Our findings shed light on the role of TPH2 gene variance in physiology and behavioral traits, and also contribute to the understanding of the pathophysiology and genetics of SIB 相似文献