Experimental study of needle-tissue interaction forces: effect of needle geometries, insertion methods and tissue characteristics.

A thorough understanding of needle-tissue interaction mechanics is necessary to optimize needle design, achieve robotically needle steering, and establish surgical simulation system. It is obvious that the interaction is influenced by numerous variable parameters, which are divided into three categories: needle geometries, insertion methods, and tissue characteristics. A series of experiments are performed to explore the effect of influence factors (material samples n=5 for each factor) on the insertion force. Data were collected from different biological tissues and a special tissue-equivalent phantom with similar mechanical properties, using a 1-DOF mechanical testing system instrumented with a 6-DOF force/torque (F/T) sensor. The experimental results indicate that three basic phases (deformation, insertion, and extraction phase) are existent during needle penetration. Needle diameter (0.7-3.2mm), needle tip (blunt, diamond, conical, and beveled) and bevel angle (10-85°) are turned out to have a great influence on insertion force, so do the insertion velocity (0.5-10mm/s), drive mode (robot-assisted and hand-held), and the insertion process (interrupted and continuous). Different tissues such as skin, muscle, fat, liver capsule and vessel are proved to generate various force cures, which can contribute to the judgement of the needle position and provide efficient insertion strategy

Enhancing the vocal range of single-speaker singing voice synthesis with melody-unsupervised pre-training

The single-speaker singing voice synthesis (SVS) usually underperforms at pitch values that are out of the singer's vocal range or associated with limited training samples. Based on our previous work, this work proposes a melody-unsupervised multi-speaker pre-training method conducted on a multi-singer dataset to enhance the vocal range of the single-speaker, while not degrading the timbre similarity. This pre-training method can be deployed to a large-scale multi-singer dataset, which only contains audio-and-lyrics pairs without phonemic timing information and pitch annotation. Specifically, in the pre-training step, we design a phoneme predictor to produce the frame-level phoneme probability vectors as the phonemic timing information and a speaker encoder to model the timbre variations of different singers, and directly estimate the frame-level f0 values from the audio to provide the pitch information. These pre-trained model parameters are delivered into the fine-tuning step as prior knowledge to enhance the single speaker's vocal range. Moreover, this work also contributes to improving the sound quality and rhythm naturalness of the synthesized singing voices. It is the first to introduce a differentiable duration regulator to improve the rhythm naturalness of the synthesized voice, and a bi-directional flow model to improve the sound quality. Experimental results verify that the proposed SVS system outperforms the baseline on both sound quality and naturalness

Ride comfort analysis of a nonlinear vehicle excited by the consecutive speed-control humps

The consecutive speed-control humps (SCHs) possess the function of controlling speed forcibly, but cause violent vibration of a vehicle inevitably. This paper tries to further explore the inherent link among parameters of the SCHs, velocity and vehicle vibration. A 4-DOF nonlinear half-vehicle model with nonlinear springs and nonlinear dampers is established. The consecutive SCHs-speed coupling excitation function is presented by combination of trapezoidal and sine wave of constant amplitude and variable frequency. The nonlinear dynamics of half-vehicle model is investigated by numerical simulation. It reveals that various forms of vibrations, such as periodic, quasi-periodic and chaotic vibrations, could appear in the system with the change of the velocity. Further it is found that quasi-periodic motions will affect vehicle ride comfort most and can be avoided by changing parameters of the consecutive SCHs. Results are conductive to deep understanding of nonlinear vibration in vehicle and rational design of the consecutive SCHs

Analyses of a Panel of Transcripts Identified From a Small Sample Size and Construction of RNA Networks in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. Dysregulation of mRNAs and non-coding RNAs (ncRNAs) plays critical roles in the progression of HCC. Here, we investigated HCC samples by RNA-seq and identified a series of dysregulated RNAs in HCC. Various bioinformatics analyses established long non-coding RNA (lncRNA)-mRNA co-expression and competing endogenous RNA (ceRNA) networks in circRNA-miRNA-mRNA axis, indicating the potential cis and/or trans regulatory roles of lncRNAs and circRNAs. Moreover, GO pathway analysis showed that these identified RNAs were associated with many biological processes that were related to tumorigenesis and tumor progression. In conclusion, we systematically established functional networks of lncRNA-mRNA, circRNA-miRNA-mRNA to further unveil the potential interactions and biological processes in HCC. These results provide further insights into gene expression network of HCC and may assist future diagnosis of HCC

Collaborative Route Planning of UAVs, Workers and Cars for Crowdsensing in Disaster Response

Efficiently obtaining the up-to-date information in the disaster-stricken area is the key to successful disaster response. Unmanned aerial vehicles (UAVs), workers and cars can collaborate to accomplish sensing tasks, such as data collection, in disaster-stricken areas. In this paper, we explicitly address the route planning for a group of agents, including UAVs, workers, and cars, with the goal of maximizing the task completion rate. We propose MANF-RL-RP, a heterogeneous multi-agent route planning algorithm that incorporates several efficient designs, including global-local dual information processing and a tailored model structure for heterogeneous multi-agent systems. Global-local dual information processing encompasses the extraction and dissemination of spatial features from global information, as well as the partitioning and filtering of local information from individual agents. Regarding the construction of the model structure for heterogeneous multi-agent, we perform the following work. We design the same data structure to represent the states of different agents, prove the Markovian property of the decision-making process of agents to simplify the model structure, and also design a reasonable reward function to train the model. Finally, we conducted detailed experiments based on the rich simulation data. In comparison to the baseline algorithms, namely Greedy-SC-RP and MANF-DNN-RP, MANF-RL-RP has exhibited a significant improvement in terms of task completion rate

Mindfulness, Psychological Distress, and Somatic Symptoms Among Women Engaged in Sex Work in China

Women engaged in sex work (WSW) in China encounter numerous disadvantages (e.g., exposure to violence) and have substantial risk for psychological distress and somatic symptoms. Intervention literature has attended to mindfulness, which is a protective factor for psychological outcomes, and its influences can further improve physical health. However, mindfulness has not been well studied in WSW. We aimed to examine the association among mindfulness, psychological distress, and somatic symptoms among Chinese WSW. Data were collected from 410 WSW in Guangxi, China, using an anonymous, self-administered survey evaluating demographics, mindfulness, psychological distress (i.e., depression, loneliness, and perceived stress), and somatic symptoms (i.e., pain, cardiopulmonary, and gastrointestinal/fatigue symptoms). Structural equation modeling was utilized for data analyses. Mindfulness was negatively associated with psychological distress and somatic symptoms. Psychological distress was positively associated with somatic symptoms. Psychological distress mediated the association between mindfulness and somatic symptoms. Mindfulness appears to be a protective factor for psychological distress among WSW, and such an effect is further influential to their somatic symptoms. Our findings add to the growing literature on mindfulness, suggesting that mindfulness-based interventions could be beneficial for WSW. Future research should explore other cognitive factors underlying the psychosomatic mechanism of mindfulness

The Role of ICT in Antiretroviral Therapy-Related Knowledge Seeking Among Older Chinese Living With HIV

Antiretroviral therapy (ART) enables HIV patients to reduce disease progression. ART adherence is closely related to patients’ knowledge about the medical treatment. This study investigated the role of information and communication technologies (ICTs) in supporting ART-related knowledge seeking among older Chinese with HIV, using cross-sectional data collected from 2012 to 2013 in Guangxi, China. Of the 2987 HIV patients, 688 were 45 years or older and going through ART. We used an 11-item scale (α=0.69), which was developed based on existing literature, to assess ART-related knowledge to obtain a composite score (0-11). Less than 5% of the participants sought HIV-related information via computers. Patients with lower ART-related knowledge were more likely to consult medical professionals about the disease via cell phones than those with higher scores (8.28 vs. 9.45, p \u3c 0.001). The results suggest that future interventions should integrate cell phones to promote ART-related knowledge dissemination among older patients

Attitudes Toward Evidence-Based Practice, Occupational Stress and Work-Related Social Support Among Health Care Providers in China: A SEM Analysis

Individuals’ attitudes toward evidence-based practices (EBP) are critical in adopting, implementing and maintaining the EBP in clinical settings. Multiple empirical studies have examined how work context may shape perceptions and attitudes towards EBP. The current study aims to further explore how both work and family contexts, as assessed by three psychosocial indicators (i.e., occupational stress, work-related social support from coworkers, and work-related social support from family), may affect attitudes toward EBP among health care providers in HIV clinics in China. We analyzed cross-sectional survey data from 357 health care providers recruited from 40 HIV clinics across 16 cities/counties in Guangxi China. Structural equation model (SEM) was constructed to test the hypothesized relationships among key study variables. Occupational stress was negatively associated with work-related social support from coworkers (β = -.19, 95%CI = [-.31,-.12]), which in turn was positively associated with attitudes toward EBP (β = .17, 95%CI = [.04, .30]). Similarly, occupational stress was negatively related to work-related social support from family (β = -.34, 95%CI = [-.42,-.25]), which in turn was positively related to attitudes toward EBP (β = .23, 95%CI = [.12, .35]). Occupational stress was negatively associated with attitudes toward EBP, but the magnitude of association did not reach statistical significance at α = .05. Work-related social support from family partially mediated the association between occupational stress and attitudes toward EBP (Sobel’s z = 3.27, p \u3c .05). Our findings suggest the importance of integrating work and family contexts, especially family support into the strategies of facilitating the adoption and implementation of EBP. The current study also underscores the needs to reduce occupational stress and enhance work-related social support among health care providers who are in frequent contact with HIV patients. In addition, lack of work-related family support may be a main barrier preventing health care providers from developing a positive attitude toward EBP. Therefore, the interventions aiming for promoting adoption and utilization of EBP need to involve specific strategies to resolve work-family conflicts and improve family members’ understanding and support for health care providers in China, especially those who work in a stressful work context such as HIV care

Mindfulness, Psychological Distress, and Somatic Symptoms Among Women Engaged in Sex Work in China

Women engaged in sex work (WSW) in China encounter numerous disadvantages (e.g., exposure to violence) and have substantial risk for psychological distress and somatic symptoms. Intervention literature has attended to mindfulness, which is a protective factor for psychological outcomes, and its influences can further improve physical health. However, mindfulness has not been well studied in WSW. We aimed to examine the association among mindfulness, psychological distress, and somatic symptoms among Chinese WSW. Data were collected from 410 WSW in Guangxi, China, using an anonymous, self-administered survey evaluating demographics, mindfulness, psychological distress (i.e., depression, loneliness, and perceived stress), and somatic symptoms (i.e., pain, cardiopulmonary, and gastrointestinal/fatigue symptoms). Structural equation modeling was utilized for data analyses. Mindfulness was negatively associated with psychological distress and somatic symptoms. Psychological distress was positively associated with somatic symptoms. Psychological distress mediated the association between mindfulness and somatic symptoms. Mindfulness appears to be a protective factor for psychological distress among WSW, and such an effect is further influential to their somatic symptoms. Our findings add to the growing literature on mindfulness, suggesting that mindfulness based interventions could be beneficial for WSW. Future research should explore other cognitive factors underlying the psychosomatic mechanism of mindfulness