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Self-efficacy is a pivotal factor in the etiology and prognosis of major depression. However, longitudinal studies on the relationship between self-efficacy and major depressive disorder (MDD) are scarce. The objectives were to investigate: (1) the associations between self-efficacy and the 1-year and 2-year risks of first onset of MDD and (2) the associations between self-efficacy and the 1-year and 2-year risks of the persistence/recurrence of MDD, in a sample of first-year university students.
We followed 8079 first-year university students for 2 years from April 2018 to October 2020. MDD was ascertained by the Chinese version of the Composite International Diagnostic Interview (CIDI-3.0) based on self-report. Self-efficacy was measured by the 10-item General Self-efficacy (GSE) scale. Random effect logistic regression modeling was used to estimate the associations.
Among participants without a lifetime MDD, the data showed that participants with high baseline GSE scores were associated with a higher risk of first onset of MDD over 2 years [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01–1.08]. Among those with a lifetime MDD, participants with high baseline GSE scores were less likely to have had a MDD over 2 years (OR 0.93, 95% CI 0.88–0.99) compared to others.
A high level of GSE may be protective of the risk of persistent or recurrent MDD. More longitudinal studies in university students are needed to further investigate the impact of GSE on the first onset of MDD.
Multivariable risk algorithms (MVRP) predicting the personal risk of depression will form an important component of personalized preventive interventions. However, it is unknown whether providing personalized depression risk will lead to unintended psychological harms. The objectives of this study were to evaluate the impact of providing personalized depression risk on non-specific psychological distress and functional impairment over 12 months.
A mixed-methods randomized controlled trial was conducted in 358 males and 354 females who were at high risk of having a major depressive episode according to sex-specific MVRPs, and who were randomly recruited across Canada. Participants were assessed at baseline, 6 and 12 months.
Over 93% of participants were interested in knowing their depression risk. The intervention group had a greater reduction in K10 score over 12 months than the control group; complete-case analysis found a significant between-group difference in mean K10 change score (d = 1.17, 95% CI 0.12–2.23) at 12 months. Participants in the intervention group also reported significantly less functional impairment in the domains of home and work/school activities, than did those in the control group. A majority of the qualitative interviewees commented that personalized depression risk information does not have a negative impact on physical and mental health.
This study found no evidence that providing personalized depression risk information will lead to worsening psychological distress, functional impairment, and absenteeism. Provision of personalized depression risk information may have positive impacts on non-specific psychological distress and functioning.
Understanding the patterns of treatment response is critical for the treatment of patients with schizophrenia; one way to achieve this is through using a longitudinal dynamic process study design.
This study aims to explore the response trajectory of antipsychotics and compare the treatment responses of seven different antipsychotics over 6 weeks in patients with schizoprenia (trial registration: Chinese Clinical Trials Registry Identifier: ChiCTR-TRC-10000934).
Data were collected from a multicentre, randomised open-label clinical trial. Patients were evaluated with the Positive and Negative Syndrome Scale (PANSS) at baseline and follow-up at weeks 2, 4 and 6. Trajectory groups were classified by the method of k-means cluster modelling for longitudinal data. Trajectory analyses were also employed for the seven antipsychotic groups.
The early treatment response trajectories were classified into a high-trajectory group of better responders and a low-trajectory group of worse responders. The results of trajectory analysis showed differences compared with the classification method characterised by a 50% reduction in PANSS scores at week 6. A total of 349 patients were inconsistently grouped by the two methods, with a significant difference in the composition ratio of treatment response groups using these two methods (χ2 = 43.37, P < 0.001). There was no differential contribution of high- and low trajectories to different drugs (χ2 = 12.52, P = 0.051); olanzapine and risperidone, which had a larger proportion in the >50% reduction at week 6, performed better than aripiprazole, quetiapine, ziprasidone and perphenazine.
The trajectory analysis of treatment response to schizophrenia revealed two distinct trajectories. Comparing the treatment responses to different antipsychotics through longitudinal analysis may offer a new perspective for evaluating antipsychotics.
Adults with significant childhood trauma and/or serious mental illness may exhibit persistent structural brain changes within limbic structures, including the amygdala. Little is known about the structure of the amygdala prior to the onset of SMI, despite the relatively high prevalence of trauma in at-risk youth.
Data were gathered from the Canadian Psychiatric Risk and Outcome study. A total of 182 youth with a mean age of 18.3 years completed T1-weighted MRI scans along with clinical assessments that included questionnaires on symptoms of depression and anxiety. Participants also completed the Childhood Trauma and Abuse Scale. We used a novel subfield-specific amygdala segmentation workflow as a part of FreeSurfer 6.0 to examine amygdala structure.
Participants with higher trauma scores were more likely to have smaller amygdala volumes, particularly within the basal regions. Among various types of childhood trauma, sexual and physical abuse had the largest effects on amygdala subregions. Abuse-related differences in the right basal region mediated the severity of depression and anxiety symptoms, even though no participants met criteria for clinical diagnosis at the time of assessment.
The experience of physical or sexual abuse may leave detectable structural alterations in key regions of the amygdala, potentially mediating the risk of psychopathology in trauma-exposed youth.
Amnestic mild cognitive impairment (aMCI) is characterized by delayed P300 latency and reduced grey matter (GM) volume, respectively. The relationship between the features in aMCI is unclear. This study was to investigate the relationship between the altered P300 latency and the GM volume in aMCI.
Thirty-four aMCI and 34 well-matched normal controls (NC) were studied using electroencephalogram during a visual oddball task and scanned with MRI. Both tests were finished in the same day.
As compared with the NC group, the aMCI group exhibited delayed P300 latency in parietal cortex and reduced GM volumes in bilateral temporal pole and left hippocampus/parahippocampal gyrus. A remarkable negative correlation was found between delayed P300 latency and reduced left hippocampal volume only in the aMCI group. Interestingly, the mediating analysis found P300 latency significantly mediated the association between right supramarginal gyrus volume and information processing speed indicated by Stroop Color and Word Test A scores.
The association between delayed P300 latency and reduced left hippocampal volume in aMCI subjects suggests that reduced left hippocampal volume may be the potential structural basis of delayed P300 latency.
Fingerprint-based indoor localisation suffers from influences such as fingerprint pre-collection, environment changes and expending a lot of manpower and time to update the radio map. To solve the problem, we propose an efficient radio map updating algorithm based on K-Means and Gaussian Process Regression (KMGPR). The algorithm builds a Gaussian Process Regression (GPR) predictive model based on a Gaussian mean function and realises the update of the radio map using K-Means. We have conducted experiments to evaluate the performance of the proposed algorithm and results show that GPR using the Gaussian mean function improves localisation accuracy by about 13·76% compared with other functions and KMGPR can reduce the computational complexity by about 7% to 20% with no obvious effects on accuracy.
The observability of error states in Inertial Navigation System/Global Positioning System (INS/GPS) integration is of great importance. Rank tests or null space tests of the observability matrix have been adopted by previous works, however, for a time-varying system with a high-dimension error state vector, it is very difficult to analyse the observability matrix by these traditional methods. In this paper, the decoupled observability analysis method is proposed for an 18-dimensional INS/GPS integration system. By reducing the dimension of coupling error states, several six-dimensional decoupled observability sub-matrices are obtained, which make the observability analyses easier. The observability results of error states are obtained by the proposed method. Covariance simulation with an Extended Kalman filter (EKF) and a flying test were performed which confirmed the theoretical results.
Background: Investigations of mental health literacy are important because the recognition of a mental health problem is the first step in seeking appropriate mental health care. Lack of recognition is a significant barrier to accessing mental health resources. Older Chinese immigrants are at increased risk for depression; however, there is no research investigating their depression literacy, including their beliefs about treatment, etiology, and prognosis.
Methods: This study investigated depression literacy among 53 older Chinese immigrants in Canada (aged 55–87 years) and compared their literacy to Canadian-born participants of the same age who were part of a larger population-based survey. Depression literacy was assessed through interviews using a case vignette and included the following indices: rates of correct identification of depression; perceived efficacy of various people, professions and treatments; and perceptions of etiology and prognosis.
Results: In the Chinese sample, 11.3% correctly identified depression in the case vignette. In contrast, 74.0% of participants in the population-based survey correctly identified depression. Differences in the perceptions of helpful people and interventions, etiology, and prognosis were also noted between the samples. Both samples strongly endorsed physical activity as helpful in the treatment of depression.
Conclusions: In light of these results, it is clear that older Chinese immigrants would benefit from information regarding the symptoms, etiology, and treatment of depression, and that this information may begin to address the serious underutilization of mental health services among this group. Our discussion highlights practice implications and promising interventions.
The microstructures and mechanical properties of Mg–6Zn–5Al–4Gd–1RE (RE = Ce or Y) alloys were investigated. The addition of Ce or Y obviously refines the grain size for the Mg–6Zn–5Al–4Gd-based alloy, while the Y element has a better refining effect. The Ce and Y show different grain-refining mechanisms: Ce addition mostly promotes the growth of secondary dendrite, while Y addition mainly increases the heterogeneous nucleation sites. The hardness-versus-aging time curves indicate that all the alloys have excellent aging-hardening behavior, but the response to maximum hardness was delayed by the Ce or Y addition. The microstructure observation of the peak-aged alloys indicated a large number of nanocrystalline τ-Mg32(Al, Zn)49 precipitates in the matrix. The Y addition is beneficial to improve the mechanical properties, and the alloy has optimal values. However, the Ce addition decreases the ultimate tensile strength and elongation of the alloy due to formation of a lot of shrinkage porosities.
Background. Few epidemiological studies have examined the temporal relationship between chronic pain and depression using longitudinal data. In the present study, we examined major depression as both an antecedent risk factor and consequence of chronic back pain (CBP) in the general population.
Method. Data on 9909 pain-free individuals 15 years and older with no history of back problems were drawn from cycle 1 of the National Population Health Survey and followed up 24 months later. Major depression was assessed using a structured diagnostic interview.
Results. At cycle 2, the rate of new cases of CBP in persons who were depressed at cycle 1 was 3·6% compared to 1·1% in non-depressed persons. Compared to pain-free individuals, new cases of CBP were more likely to perceive their health status as poor or fair at cycle 1, were less likely to be working, reported more chronic health problems, and sustained a back or neck injury in the preceding 12 months. After controlling for other factors, pain-free individuals diagnosed as major depressed at cycle 1 were almost three times more likely (OR 2·9, 95% CI 1·2–7·0) to develop CBP at cycle 2.
Conclusions. Consistent with other longitudinal studies major depression increases the risk of developing future chronic pain. The causal mechanism linking these conditions is unknown however depression may represent a modifiable risk factor in the development of CBP.
Background. Major depression is a prevalent mental disorder in the general population, with a multi-factorial etiology. However, work stress as a risk factor for major depression has not been well studied.
Method. Using a longitudinal study design, this analysis investigated the association between the levels of work stress and major depressive episode(s) in the Canadian working population, aged 18 to 64 years. Data from the longitudinal cohort of the Canadian National Population Health Survey (NPHS) were used (n=6663). The NPHS participants who did not have major depressive episodes (MDE) at baseline (1994–1995 NPHS) were classified into four groups by the quartile values of the baseline work stress scores. The proportion of MDE of each group was calculated using the 1996–1997 NPHS data.
Results. The first three quartile groups had a similar risk of MDE. Those who had a work stress score above the 75th percentile had an elevated risk of MDE (7·1%). Using the 75th percentile as a cut-off, work stress was significantly associated with the risk of MDE in multivariate analysis (odds ratio=2·35, 95% confidence interval 1·54–3·77). Other factors associated with MDE in multivariate analysis included educational level, number of chronic medical illnesses and child and adulthood traumatic events. There was no evidence of effect modification between work stress and selected sociodemographic, clinical and psychosocial variables.
Conclusions. Work stress is an independent risk factor for the development of MDE in the working population. Strategies to improve working environment are needed to keep workers mentally healthy and productive.
Miniature and microscale fuel processors that incorporate novel catalysts and microtechnology-based designs are discussed. The novel catalyst allows for methanol reforming at high gas hourly space velocities of 50,000 hr-1 or higher while maintaining a carbon monoxide levels at 1% or less. The microtechnology-based designs extremely compact and lightweight devices. The miniature fuel processors, with a volume less than 25 cm3, a mass less than 200 grams, and thermal efficiencies of up to 83%, nominally provide 25 to 50 watts equivalent of hydrogen, which is ample for the portable power supplies described here. With reasonable assumptions on fuel cell efficiencies, anode gas and water management, parasitic power loss, the energy density was estimated at 1700 Whr/kg. These processors have been demonstrated with a CO cleanup method and a fuel cell stack. The microscale fuel processors, with a volume of less than 0.25 cm3 and a mass of less than 1 gram, are designed to provide up to 0.3 watt equivalent of power with efficiencies over 20%.
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