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Abstract Previous studies in small samples have identified inconsistent cortical abnormalities in major depressive disorder (MDD). Despite genetic influences on MDD and the brain, it is unclear how genetic risk for MDD is translated into spatially patterned cortical vulnerability. Here, we initially examined voxel-wise differences in cortical function and structure using the largest multi-modal MRI data from 1660 MDD patients and 1341 controls. Combined with the Allen Human Brain Atlas, we then adopted transcription-neuroimaging spatial correlation and the newly developed ensemble-based gene category enrichment analysis to identify gene categories with expression related to cortical changes in MDD. Results showed that patients had relatively circumscribed impairments in local functional properties and broadly distributed disruptions in global functional connectivity, consistently characterized by hyper-function in associative areas and hypo-function in primary regions. Moreover, the local functional alterations were correlated with genes enriched for biological functions related to MDD in general (e.g., endoplasmic reticulum stress, mitogen-activated protein kinase, histone acetylation, and DNA methylation); and the global functional connectivity changes were associated with not only MDD-general, but also brain-relevant genes (e.g., neuron, synapse, axon, glial cell, and neurotransmitters). Our findings may provide important insights into the transcriptomic signatures of regional cortical vulnerability to MDD.

Objective: In order to solve the problem of manual weighting of dragon fruit, including time-consuming, laborious and expensive, an automated weight estimation method based on machine vision and machine learning was proposed in this research. Methods: Firstly, 106 dragon fruits were weighed, recorded and photographed, and images of dragon fruits were constructed. Secondly, binary images were obtained after denoising and segmentation. Moreover, the three features of pixel area, major axis pixel length and minor axis pixel length of dragon fruits were extracted on the basis of binary images. The three features of each image and their corresponding weights were combined into a set of data, which was divided into training set and test set according to the ratio of 7∶3. Finally, the training set was input into the Gradient Boosting, Random Forest, K-Neighbors and Artificial Neural Networks machine-learning models for training, and the test sets were used for model evaluation. Results: The evaluation index of the Artificial Neural network performed well compared with other models, with R2 of 0.986 and RMSE of 13.091. Conclusion: The experimental result demonstrates that the method proposed in this research can accomplish the weight estimation of dragon fruit effectively, and meet the weight estimation requirements of dragon fruit.

This paper presents the design of a sliding mode controller to compensate hysteresis nonlinearity and achieve precision motion tracking for a novel piezoelectric tip/tilt platform driven by a PZT actuator. The sliding mode control scheme is based on the unique physical characteristics of the piezoelectric tip/tilt platform. The proposed scheme effectively guides the platform state onto a predefined sliding surface and ensures its sustained movement along this manifold. This approach reduces tracking errors compared to conventional methodologies. The stability of the sliding mode control scheme is demonstrated by the Lyapunov theory framework. It achieves precise motion control with minimal tracking error on a piezoelectric tip/tilt platform. The properties of the controller have been confirmed through experimental tests. The proposed control scheme enhances the robust tracking and stability performance on the piezoelectric tip/tilt platform, outperforming traditional control schemes. Compared with the P562.6CD produced by PI Germany, the proposed innovative approach not only boosts the platform’s resolution by 32% but also implements a 33% reduction in cost.

Waterborne epoxy coating is an environmentally friendly anticorrosion coating that are gradually attracting people's attention. However, the anticorrosion performance of waterborne epoxy coatings is unsatisfactory. It is found that the incorporation of some nanomaterials can remarkably improve the anticorrosion properties of waterborne epoxy coatings. This study reports an environmental-friendly waterborne epoxy (EP) coating with enhanced corrosion protection performance by embedding prepared octadecylamine-attapulgite-graphene (ODA-ATP-G) nanocomposite. By the analysis of electrochemical impedance spectroscopy (EIS), it is found that ODA-ATP-G nanocomposites can significantly improve the corrosion resistance of waterborne epoxy coating and provide long-time corrosion protection for the steel substrate. Through the analysis of UV–Visible Near Infrared Spectrophotometer, SEM, EDS and Raman, it is demonstrated that the reinforcement effect of ODA-ATP-G nanocomposites should be attributed to the barrier effect of ODA-ATP-G nanocomposite, the formation of hydrophobic protective film on the steel surface with the adsorption and deposition of ODA.

Based on the potential energy method, an algorithm for modifying the meshing stiffness of helical gears is proposed. This method considers the real machining of the tooth root transition curve, which is a trajectory line formed by the tip angle of the tooth when the tool rolls into motion, and the starting point of the involute is the intersection of the tooth root transition curve and the involute. When calculating the stiffness, the tooth root transition curve equation from the root of the tooth to the starting point of the involute is used for the calculation, and the involute equation from the starting point of the involute to the top of the tooth is used in the calculation. The meshing stiffness calculated by this method is closer to the reality. Compared with the finite element method, the accuracy of the modified algorithm is verified and the calculation accuracy of the helical gear meshing stiffness is improved. Based on this method, the influence of involute shape, meshing position and contact ratio on the meshing stiffness and transmission error of helical gears is analyzed. The research results show that when the pressure angle increases, the radius of curvature of involute will increase. Thus the transverse stiffness of gears is improved. At the same time, the transverse contact ratio will firstly increase and then decrease. Under the influence of transverse stiffness and transverse contact ratio, the variation trend of average meshing stiffness is the same as that of transverse contact ratio; when the meshing position is closer to the node, the meshing stiffness will increase; an increased total contact ratio will make the average stiffness increase, and the transmission error (TE) decrease as a whole. However, when the contact ratio is close to the odd multiple of 0.5, the TE peak-to-peak value will reach a maximum value.

Stigma poses considerable challenges to the mental health of people living with HIV who use drugs (PLHWUD). In this study, we explored factors related to different types of stigma (perceived and internalized) attached to layered stigmatizing characters (HIV and drug use) and their mental health influences on PLHWUD. The study used baseline data of an ongoing randomized controlled trial among 241 PLHWUD recruited between March and December 2018 in Vietnam. A structural equation model was used to assess the relationships among different types and layers of stigma and mental health status. Both perceived and internalized drug-related stigma measures were significantly higher than their corresponding HIV-related stigma. HIV-related stigma was negatively associated with mental health status; however, we did not find a significant relationship between drug-related stigma and mental health. Tailored intervention strategies in consideration of types and layers of stigma are needed to address stigma-related challenges faced by PLHWUD.

HCV co-infection is widespread among people living with HIV who use drugs (PLHWUD). However, HCV testing was inconsistently implemented among PLHWUD. The low infection awareness and mental health challenges together impede PLHWUD's treatment-seeking. The study used baseline data of a randomized controlled trial conducted in Vietnam. HCV infection status was collected through self-report and medical record review. A linear mixed-effects regression model was used to examine the relationships between PLHWUD's perceived barriers to seeking healthcare, their depressive symptoms, and the consistencies in HCV status reports. Among the 181 PLHWUD in the study, one-third (64; 35.4%) had inconsistent self-reports and medical records of HIV infection status. The agreement between the two records was fair (Kappa statistics = 0.43). PLHWUD with consistent HCV infection confirmed by both medical records and self-reports perceived lower levels of healthcare-seeking barriers than those with discrepant HCV reports (estimated difference = -1.59, SE = 0.71, P = 0.027). Depressive symptoms were significantly correlated with healthcare-seeking barriers among those with discrepant HCV results (estimate = 0.17, SE = 0.06, P = 0.007). There is an urgent need to extend HCV screening efforts and increase HCV awareness among PLHWUD. Explicit HCV result notification and integrated mental health support are recommended to facilitate patients' access to needed care.

This study compared community health workers' (CHW) stigma towards people living with HIV (PLH) and people who use drugs (PWUD) and explored the relationship between stigma and CHWs' confidence level in providing HIV/drug-related services. Using two sets of identically worded questions, levels of stigma towards PWUD and PLH were measured among 120 CHW from 60 communes in Vietnam. The associations between CHWs' confidence in service provision and stigma towards PWUD and PLH were examined using a linear mixed-effects regression model. The majority of the CHW reported higher levels of stigma towards PWUD than towards PLH. Compared to the CHW reporting higher stigma towards PWUD, those with higher stigma towards PLH were significantly less confident in service provision. Social opprobrium attached to drug-using behaviors can be a major driver behind the overall HIV stigma. CHWs' fear of HIV infection should be tackled to boost their confidence in HIV/drug-related care provision.