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1.
This study investigated the gender-specific, self-reported sexual behaviors and attitudes of never-married college students attending a southeastern university in 1973 and 1988. Data were collected by means of a mailed questionnaire that remained essentially unchanged for both years. The authors found that both men and women reported an increase in heterosexual relationships that included sexual intercourse and a decrease in nonsexual relationships with the other gender. The majority of the students perceived themselves as adequately informed about sexuality and satisfied with their relationships, although the proportion of men who reported being satisfied with their relationships declined over the 15 years. The students indicated that sexuality education should focus primarily on information about AIDS and on preparation for marriage.  相似文献   
2.
V.A. Knight  P.R. Harper  L. Smith 《Omega》2012,40(6):918-926
This paper proposes new models for locating emergency medical services (EMS) by incorporating survival functions for capturing multiple-classes of heterogeneous patients. The Maximal Expected Survival Location Model for Heterogeneous Patients (MESLMHP) aims to maximize the overall expected survival probability of multiple-classes of patients, whereby different classes could be defined according to agreed patient categories based on response time targets, or by capturing differing medical conditions each with a corresponding survival function. Furthermore, we propose and demonstrate an approximation approach to solving the extended stochastic version of MESLMHP, which utilizes queuing theory to permit the modeling of congestion and utilization at each ambulance station, and does not require assumptions to be made on the utilization of ambulances. Both models are demonstrated using data from the ambulance service in Wales. We show that our multiple outcome measures and survival-maximizing approach, rather than one based on average response time targets alone or a single patient class provides more effective EMS ambulance allocations.  相似文献   
3.
This study assesses the degree to which the relationship between the environmental demands of countries (measured as ecological footprint per capita) and well-being (measured as life expectancy) has changed over the last several decades (1961–2007) and whether the nature and extent of these changes differ between developed and less-developed countries. Pooled ordinary least squares regression results indicate that decoupling has occurred among developed countries, where the relationship between ecological footprint and life expectancy weakened substantially over time, becoming negative in later years. In less-developed countries, the relationship has intensified substantially, with the effect of ecological footprint on life expectancy becoming stronger over time. Fixed-effects regression results provide similar results for developed countries but indicate slight decoupling between increases in ecological footprint and life expectancy among less-developed countries. The implications of these results are discussed in the context of contraction and convergence approaches to sustainability.  相似文献   
4.
Statistics and Computing - Long memory has been observed for time series across a multitude of fields, and the accurate estimation of such dependence, for example via the Hurst exponent, is crucial...  相似文献   
5.
Pathological gambling (PG) is an impulse control disorder that has been considered as a behavioral addiction. Recent studies have suggested the involvement of the dopaminergic system in addictions and impulse control disorders and associations of dopamine receptor genes (DRD1, DRD2, and DRD4) and PG have been reported. In the present study, 140 sib-pairs discordant for the diagnosis of PG (70 males and 70 females on each group) were recruited through the Gambling Outpatient Unit at the Institute of Psychiatry, University of Sao Paulo and were assessed by trained psychiatrists. A family-based association design was chosen to prevent population stratification. All subjects were genotyped for dopamine receptor genes (DRD1 -800 T/C, DRD2 TaqIA RFLP, DRD3 Ser9Gly, DRD4 48bp exon III VNTR, DRD5 (CA) repeat) and the dopamine transporter gene (SCL6A3 40 bp VNTR). Our results suggest the association of PG with DRD1 -800 T/C allele T (P = .03).  相似文献   
6.
Using longitudinal Swedish data from 1,373 early‐adolescent youths, this study aims to answer the question of whether the previously established protective function of parental knowledge and its sources—adolescent disclosure, parental solicitation, and parental control—on substance use among early‐adolescents is moderated by the adolescent's temperament. Adolescent temperament moderated several links between parental knowledge and its sources and adolescent substance use. The most pronounced moderating results were found for those adolescents with fearless, socially detached and thrill‐seeking tendencies. For these “detached thrill‐seekers”, bidirectional links between adolescent disclosure and substance use, and negative links between parental solicitation and substance use were found. We recommend, therefore, that adolescent temperament is considered when designing parenting programs.  相似文献   
7.
This research focuses on enrolment in advanced level Mathematics and Physics in secondary school among first and second generations of Former Soviet Union immigrants and third generation Israeli‐born Jews. The article made use of the Israeli Ministry of Education's database, which includes data on all students who finished their secondary education with a matriculation certificate in 2013. Our findings show the advantage of enrolment in Physics, which is perceived as the most difficult subject, among FSU immigrant students compared to the third generation of Israeli‐born students. This advantage may be explained by their STEM (Science, Technology, Engineering and Mathematics)‐related cultural capital. However, first‐generation FSU students were less likely to be enrolled in advanced‐level Mathematics compared to third‐generation Jews. These findings may emphasize the role of the Israeli education system as a gatekeeper in entering more prestigious Mathematics.  相似文献   
8.
Classical nondecimated wavelet transforms are attractive for many applications. When the data comes from complex or irregular designs, the use of second generation wavelets in nonparametric regression has proved superior to that of classical wavelets. However, the construction of a nondecimated second generation wavelet transform is not obvious. In this paper we propose a new ‘nondecimated’ lifting transform, based on the lifting algorithm which removes one coefficient at a time, and explore its behavior. Our approach also allows for embedding adaptivity in the transform, i.e. wavelet functions can be constructed such that their smoothness adjusts to the local properties of the signal. We address the problem of nonparametric regression and propose an (averaged) estimator obtained by using our nondecimated lifting technique teamed with empirical Bayes shrinkage. Simulations show that our proposed method has higher performance than competing techniques able to work on irregular data. Our construction also opens avenues for generating a ‘best’ representation, which we shall explore.  相似文献   
9.
This study examines changes over time in ethnic affirmation/belonging and ethnic identity achievement, Spanish language use, English language use, Mexican/Mexican‐American affiliation/identification and Anglo affiliation/identification in a sample of Mexican‐American adolescents participating in a longitudinal study of juvenile offenders. The Multigroup Ethnic Identity Measure and the Acculturation Rating Scale for Mexican Americans‐II were completed by the Mexican‐American adolescents 7 times over a 3‐year period. The findings from longitudinal growth modeling analyses and growth mixture modeling analyses indicate that there is heterogeneity in the initial scores and changes over time on these variables that are related to markers for the cultural qualities of the home environment (i.e., generational status and mother's most frequent language use). In contrast to expectations, marginalized or assimilated acculturation trajectories/types were not overrepresented in this sample of adolescent offenders. Implications for our understanding of the nature of acculturation and enculturation processes and the way these processes are studied are discussed.  相似文献   
10.
Research indicates that desire and arousal problems are highly interrelated in women. Therefore, hypoactive sexual desire disorder (HSDD) and female sexual arousal disorder (FSAD) were removed from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), and a new diagnostic category, female sexual interest/arousal disorder (FSIAD), was created to include both arousal and desire difficulties. However, no research has tried to distinguish these problems based on psychosocial-physiological patterns to identify whether unique profiles exist. This study compared psychosocial-physiological patterns in a community sample of 84 women meeting DSM-IV (American Psychiatric Association, 2000 American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., text rev.). Washington, DC: Author.[Crossref] [Google Scholar]) criteria for HSDD (n = 22), FSAD (n = 18), both disorders (FSAD/HSDD; n = 25), and healthy controls (n = 19). Women completed self-report measures and watched neutral and erotic films while genital arousal (GA) and subjective arousal (SA) were measured. Results indicated that GA increased equally for all groups during the erotic condition, whereas women with HSDD and FSAD/HSDD reported less SA than controls or FSAD women. Women in the clinical groups also showed lower concordance and greater impairment on psychosocial variables as compared to controls, with women with FSAD/HSDD showing lowest functioning. Results have important implications for the classification and treatment of these difficulties.  相似文献   
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