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91.
US Air Force remote warrior personnel include a range of military personnel composed of remotely piloted aircraft aircrew, intelligence operators, and cyber warfare operators. Job duties in these professions entail long work hours, rotating shifts, and regular engagement in combat operations. Although research has identified a number of factors correlated with elevated burnout and emotional distress in this population, little is known about the unique needs of discrete subgroups of distressed personnel. In a sample of 7,550 US Air Force remote warriors, results of latent class analysis yielded four distinct classes. Three of the four reported moderately elevated burnout and job dissatisfaction but differed with respect to demographics and development career stage. The fourth group reported significantly higher levels of emotional distress, burnout, job dissatisfaction, and problems in living. This latter group was comparable to the mid-career group with respect to demographics, although this group had much lower levels of responsibility and indicators of career advancement. Results suggest that, among remote warrior personnel, there are several subtypes of elevated emotional distress. Prevention and intervention strategies that are matched to each subtype may yield better occupational and mental health outcomes than universal, “one size fits all” strategies.  相似文献   
92.
Rodents solve dual-solution tasks that require navigation to a goal by adopting either a hippocampus-dependent place strategy or a striatum-dependent stimulus-response strategy. A variety of factors, including biological sex and emotional status, influence the choice of learning strategy. In these experiments, we investigated the relationship between learning strategy and anxiety level in male and female rats prior to the onset of puberty, before the activational effects of gonadal hormones influence these processes. In the first experiment, prepubertal male rats categorized as high in trait anxiety at 26days of age exhibited a bias toward stimulus-response strategy at 28days of age, whereas age-matched females exhibited no preference in strategy regardless of anxiety level. In the second experiment, male and female rats were separated from their dams for either 15 or 180min per day during the first 2weeks of life and tested on a battery of anxiety and cognitive tasks between 25 and 29days of age. Prolonged maternal separations for 180min were associated with impaired spatial memory on a Y-maze task in both prepubertal males and females. Furthermore, prolonged maternal separations were linked to elevated anxiety and a bias for stimulus-response strategy in prepubertal males but not females. Alternatively, brief separations from dams for 15min were associated with intact spatial memory, lower levels of anxiety, and no preference for either learning strategy in both sexes. These results provide evidence of sex-specific effects of trait anxiety and early maternal separation on the choice of learning strategy used by prepubertal rodents.  相似文献   
93.
A prospective, behavioral high-risk design provided a theoretically guided examination of vulnerability to first onset of bipolar spectrum disorder based on the Behavioral Approach System (BAS) model. Adolescents (ages 14-19) at an "age of risk" for bipolar disorder onset were screened on BAS sensitivity by interviewers blind to current symptoms, lifetime history, and family history of psychopathology. Participants were selected with high versus moderate levels of BAS sensitivity and administered a lifetime diagnostic interview. Those with a bipolar spectrum disorder, psychosis, or hypomanic episode with onset prior to the BAS sensitivity assessment were excluded. High BAS (n = 171) and moderate BAS (n = 119) sensitivity participants in the final sample completed baseline measures of symptoms, goal-setting, and reward responsiveness and were followed prospectively with semistructured diagnostic interviews every 6 months. Consistent with the vulnerability hypothesis of the BAS model of bipolar disorder, high BAS participants had a greater likelihood, and shorter time to onset, of bipolar spectrum disorder than moderate BAS participants across an average of 12.8 months of follow-up (12.9% vs. 4.2%), controlling for baseline depressive and hypomanic symptoms, and family history of bipolar disorder. High reward responsiveness on a behavioral task and ambitious goal-striving for popular fame and financial success (but not impulsivity) also predicted first onset of bipolar spectrum disorder controlling for the covariates and BAS risk group, and ambitious goal-striving partially mediated the BAS risk group effect. We discuss implications of the findings for the BAS model of bipolar disorder and early intervention efforts.  相似文献   
94.
Little longitudinal research has examined progression to more severe bipolar disorders in individuals with "soft" bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a nonpatient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of "soft" bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts.  相似文献   
95.
A number of studies have consistently reported that there is a greater prevalence of mental illness among the most socioeconomically disadvantaged. At the same time, there is evidence that services are not optimally accessed by the most socioeconomically disadvantaged; the most in need of care are also the most likely to have unmet healthcare needs. Of people with mental illnesses, those with severe mental illnesses (SMI) are the most at risk of poverty and the least likely to have optimal care. In the past, specialized community mental health services have been identified as the primary provider for people with SMI. However, there is growing interest in using the primary care setting as the main source of mental health care where both medical treatment and psychotherapy can be accessed. In this paper, we examine factors related to primary care use (and in turn, pharmacologic and psychotherapies) for people who are socioeconomically disadvantaged and who have a SMI.  相似文献   
96.
Effect of contraction intensity [100%, 75%, 50%, and 25% maximum voluntary contraction (MVC)] and movement velocity [0 degrees (isometric)], 50 degrees, 100 degrees, 200 degrees, and 400 degrees/sec. [isovelocities]) on root mean square amplitude (SEMG-RMS) and median frequency power spectrum (SEMG-MNF) of vastus lateralis (VL) surface electromyography was investigated with ten healthy female university students. Peak torque (PT), mean torque (MT), SEMG-MNF, and SEMG-RMS, analyzed using separate repeated-measures analyses of variance (p < or = .05), indicated: (1) an inverse relation between PT and MT and movement velocity, (2) greater SEMG-MNF values during all isovelocity conditions compared with isometric conditions, with highest values occurring at 50 degrees /sec. and at 100% and 75% MVC, and (3) at all contraction intensities SEMG-RMS values were higher during dynamic movements than isometric movements and highest at 200 degrees /sec. Isovelocity contractions were inferred to facilitate a greater recruitment of fast-twitch fibers (via increased SEMG-MNF), which was intensified at 50 degrees /sec., whereas greater overall muscle activation was found at 200 degrees /sec.  相似文献   
97.
The p-median offers an alternative to centroid-based clustering algorithms for identifying unobserved categories. However, existing p-median formulations typically require data aggregation into a single proximity matrix, resulting in masked respondent heterogeneity. A proposed three-way formulation of the p-median problem explicitly considers heterogeneity by identifying groups of individual respondents that perceive similar category structures. Three proposed heuristics for the heterogeneous p-median (HPM) are developed and then illustrated in a consumer psychology context using a sample of undergraduate students who performed a sorting task of major U.S. retailers, as well as a through Monte Carlo analysis.  相似文献   
98.
Three experiments demonstrated learners' abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study-test cycles of the same test format, followed by a final critical cycle featuring either the expected or the unexpected test format. For final tests of both cued and free recall, participants who had expected that test format outperformed those who had not. This disordinal interaction, supported by recognition and self-report data, demonstrated not mere differences in effort based on anticipated test difficulty, but rather qualitative and appropriate differences in encoding strategies based on expected task demands. Participants also came to appropriately modulate metacognitive monitoring (Experiment 2) and study-time allocation (Experiment 3) across study-test cycles. Item and associative recognition performance, as well as self-report data, revealed shifts in encoding strategies across trials; these results were used to characterize and evaluate the different strategies that participants employed for cued versus free recall and to assess the optimality of participants' metacognitive control of encoding strategies. Taken together, these data illustrate a sophisticated form of metacognitive control, in which learners qualitatively shift encoding strategies to match the demands of anticipated tests.  相似文献   
99.
The arrest of a parent or other family member can be detrimental to children’s health. To study the impact of exposure to the arrest of a family member on children’s mental health and how said association may change across developmental periods, we examined baseline data for children (birth through 11 years) entering family-based systems of care (SOC). Children exposed to the arrest of a family member had experienced significantly more 5.38 (SD = 2.59) different types of potentially traumatic events (PTE) than children not exposed to arrest 2.84 (SD = 2.56). Multiple regression model results showed that arrest exposure was significantly associated with greater behavioral and emotional challenges after controlling for children’s age, gender, race/ethnicity, household income, caregiver’s education, parenting factors, and other PTE exposure. Further analyses revealed differences in internalizing and externalizing behaviors associated with arrest exposure across developmental levels. This study highlights some of the mental health challenges for children exposed to the arrest of a family member, while adding to our knowledge of how such an event affects children across different developmental periods. More trauma-informed, developmentally appropriate systems need to be in place at all levels to assist children and families experiencing arrest.  相似文献   
100.
Parental presence is often employed to alleviate distress in children within the context of surgery under general anesthesia. The critical component of this intervention may not be the presence of the parent per se, but more importantly the behaviors in which the parent and child engage when the parent is present. The purpose of the current study was to examine the sequential and reciprocal relationships between parental behaviors and child distress during induction of general anesthesia. Participants were 32 children (3–6 years) receiving dental surgery as a day surgery procedure, and their parents. A modified Child Adult Medical Procedures Interaction Scale-Revised was used to code parent and child behaviors. Initial child distress led to increased parental provision of reassurance and decreased provision of physical comfort. Our findings may inform the development of preoperative preparation programs whereby parents can be appropriately educated about what behaviors will be helpful/unhelpful for their child during induction of general anesthesia.  相似文献   
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