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41.
The present internet survey examined the demographic characteristics of Chinese-speaking international students in Australia, psychological distress levels as measured by the Kessler-10 (K-10) Item scale, help-seeking history and preferences, as well as treatment barriers. Of the 144 respondents, 54% reported high psychological distress (mean K-10 score?=?23.96; SD?=?9.03). However, only 9% of those who were highly distressed reported they had sought mental health services in the past year. While the majority preferred help from informal social networks, they tended to favour mental health services over traditional culture-specific forms of help. Common barriers to accessing mental health services reported by respondents with high psychological distress included costs or transportation concerns, limited knowledge of available services, time constraints, the perception that symptoms were not severe enough to warrant treatment, language difficulties and lack of knowledge of symptoms of psychological distress. Although the majority preferred face-to-face treatments over internet treatments, a considerable percentage of respondents were willing to try either treatment modality. Chinese-speaking international students are a high risk group for developing psychological distress, yet they tend to underuse mental health services. Education about the effectiveness of face-to-face and online treatments may increase treatment seeking by this population.  相似文献   
42.
On rough terrain, excessive wheel slippage is easily generated by changes of surface conditions such as soil types and geometries. It induces considerable loss of wheel traction and battery energy. To prevent this, wheeled robots should consistently recognize the current situation generated between wheel and surface. And also wheeled robots are required to optimally control wheel motion in limited wheel traction and battery capacity. Therefore, this paper proposes a novel wheel control algorithm based on slip optimization of traction and energy, which is adaptive to change of surface condition. Proposed wheel control algorithm is called Traction-Energy Balancing Adaptive Control (TEB) in this paper and TEB assigns optimized rotation speed to each wheel by observing wheel slip ratio which is a key parameter of TEB. As functions of TEB, TEB is largely divided into three main parts; (1) slip optimizer (2) slip controller (3) SC-compensator. In the slip optimizer, two optimal slip models were derived as a function of slip ratios regarding maximum traction and tractive efficiency using experimental data about wheel-terrain interaction in three types of soil (grass, gravel and sand). And the optimal slip models were employed in order to determine a desired slip value of wheel with observation of a change in actual robot velocity as control input in the slip controller. For optimal slip control, the proposed slip controller is based on conventional PID controller with compensating disturbance in the controller (SC-compensator) which occurs by change of surface shapes. In the SC-compensator, radial function networks (RBFN) was applied in the slip controller and RBFN was of help to readjust previously set PID gains depending on occurred slip error. Finally, TEB was experimentally verified by controlling a real robot having four wheels on various terrain types.  相似文献   
43.
The aim of this study was to examine socio-demographic and psychosocial correlates of concurrent tobacco use and risky drinking. We analysed data from the cross-sectional South African National Health and Nutrition Examination Survey (SANHANES-1) 2011–2012. The sample included 14 764 adolescents and adults aged 15 years and older. They responded to questions on tobacco and alcohol use, psychosocial, and socio-demographic indicators. Results indicate that 9.6% (16.8% among men and 3.5% among women) of South Africans were involved in concurrent tobacco use and risky drinking, 18.2% in current tobacco use only, and 20.3% in risky drinking only. In covariate adjusted analysis, being 25 to 64 years, being male, belonging to the coloured population group, residing in urban areas, having experienced three or more traumatic events, and poor self-rated health were associated with concurrent tobacco use and risky drinking. Findings suggest socio-demographic and health factors are important for public health interventions in addressing concurrent tobacco and alcohol use in South Africa.  相似文献   
44.
物质成瘾与反转学习损伤密切相关,成瘾者往往不能灵活地适应变化的刺激—结果的联结,这可能进一步加剧成瘾者的物质使用。近年来研究发现,物质成瘾者的反转学习相关的腹外侧前额和背外侧前额等脑区激活异常,这些异常与成瘾者的冲动性和强迫性有关。此外,个体的反转学习能力对其成瘾行为具有一定预测性。今后应增加对不同类型物质成瘾者的反转学习脑机制及物质相关线索对成瘾者反转学习影响的研究,并且进一步探讨成瘾者的冲动性和强迫性对其反转学习的调节及个体反转学习能力对其成瘾行为的预测。  相似文献   
45.
This article tested a model of parenting stress as a mediator between maternal depressive symptoms, emotion regulation, and child behavior problems using a sample of homeless, substance‐abusing mothers. Participants were 119 homeless mothers (ages 18–24 years) and their young children (ages 0–6 years). Mothers responded to questions about their depressive symptoms, emotion regulation, parenting stress, and child behavior problems. A path analysis showed that maternal depressive symptoms were positively associated with child behavior problems through increased parenting stress whereas maternal cognitive reappraisal was negatively associated with child behavior problems through decreased parenting stress. Moreover, maternal expressive suppression was negatively related to child externalizing problems. Findings support the parenting stress theory and highlight maternal parenting stress as a mechanism associated with homeless children's mental health risk. This study has significant implications for understanding the parenting processes underlying child's resilience in the context of homelessness and maternal substance use.  相似文献   
46.
Finger counting can be useful in solving arithmetic problems, noticeably because it reduces the working memory demand of mental calculations. However, proprioceptive information might not be sufficient to keep track of the number of fingers raised during problem solving, and visual input may play an important role in this process. The present study was designed to address this question and shows that 8-year-old children look at their fingers in 60% of the trials during finger counting when solving additive problems. Moreover, our results reveal that the frequency of finger looking is negatively correlated with working memory capacities and is higher for more difficult problems. These findings suggest that finger looking is recruited in managing the cognitive demand of the arithmetic task, probably by providing additional external cues to monitor the number of steps that have to be incremented during finger counting.  相似文献   
47.
We offer a new theoretical angle for cognitive arithmetic, which is that evidence accumulation may play a role in problem plausibility decisions. We build upon previous studies that have considered such a hypothesis, and here formally evaluate the paradigm. We develop the finding that performance differences, due to variations in strategy use and aging effects, can indeed be reasonably explained through these accumulation-to-bound cognitive models. Results suggest that these models may be effectively used to learn more about the underlying cognitive processes. In this study, we modelled young (18–24) and older (68–82) adults’ solution times in performing arithmetic verification (e.g. whether 8?×?5?=?41 is true/false). The domain-relevant factors in strategy use (problem-verification heuristics) and aging differences (older/younger adult groups) were analyzed by a response process model of the latency data, that is fit by participant and item. Lower thresholds accounted for the faster response times (RTs) for problems solved with heuristics (arithmetic rule-violation checking strategies), as opposed to problems solved by calculation approaches. A more rapid accumulation accounted for faster RTs on problems in which two arithmetic rules were violated (strategy combination) rather than one. Third, higher thresholds (i.e. preferring to have greater certainty before responding) accounted for older adults’ slower speed. These findings are in support of accumulation models being relevant for more complex cognitive tasks, as well as to account for the age-related differences therein.  相似文献   
48.
Substance use disorders (SUDs) are a growing problem for the U.S. military. Each branch of the military has its own dedicated substance abuse treatment program. However, there has been limited attention to the research conducted on these programs. The purpose of this narrative review is to describe SUD treatment programs in the U.S. military and to review the extant research published between 2001–2015. Fourteen peer-reviewed articles, 2 official reports, 1 book chapter, 1 thesis, and 1 dissertation were identified. Most SUD treatment programs are nonconfidential, although a confidential program is being piloted by the Army. Recently, the programs have increased their focus on assessment and treatment of comorbid psychological disorders. Further research is required to examine the efficacy, effectiveness, and cost-effectiveness of the treatment programs.  相似文献   
49.
When study is spaced across sessions (versus massed within a single session), final performance is greater after spacing. This spacing effect may have multiple causes, and according to the mediator hypothesis, part of the effect can be explained by the use of mediator-based strategies. This hypothesis proposes that when study is spaced across sessions, rather than massed within a session, more mediators will be generated that are longer lasting and hence more mediators will be available to support criterion recall. In two experiments, participants were randomly assigned to study paired associates using either a spaced or massed schedule. They reported strategy use for each item during study trials and during the final test. Consistent with the mediator hypothesis, participants who had spaced (as compared to massed) practice reported using more mediators on the final test. This use of effective mediators also statistically accounted for some – but not all of – the spacing effect on final performance.  相似文献   
50.
Tool use is typically explored via actor-tool interactions. However, the target-object (that which is being acted on) may influence perceived action possibilities and thereby guide action. Three different tool-target-object pairings were tested (Experiment 1). The hammering action demonstrated the greatest sensitivity and therefore subsequently used to further investigate target-object pairings. The hammer was removed as an option and instructions were provided using pictorial (Experiment 2), written (Experiment 3), and both pictorial and written formats (Experiment 4). The designed tool is chosen when available (Experiment 1) and when removed as a choice (i.e., the hammer), participants perform the same action associated with the designed tool (i.e., hammering) regardless of instruction method (Experiments 2, 3, and 4).  相似文献   
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