Design and evaluation of safety operation VR training system for robotic catheter surgery

A number of remote robotic catheter systems have been developed to protect physicians from X-ray exposure in endovascular surgery. However, the teleoperation prevents the physicians sensing the force directly which may easily result in healthy vessels injured. To realize the safe operation, a tissue protection-based VR training system has been developed in this paper to prevent collateral damage by collision. The integrated VR simulator cannot only remind the novice possible collisions by visual signs, but also cooperate with the newly designed tissue protection mechanism to remit collision trauma beforehand. Such mechanism exploits the diameter variable pulley in order to implement the safe interaction between catheter and vasculature. To testify the effectiveness of the tissue protection in training system, we invited four non-medical students to participate the successive 5 days training session. The evaluation results show that the average impingement distance (representing tissue damage) to vascular wall has been reduced to 0.6 mm, and the collision frequency is greatly decreased which implies the realization of relative safe catheterization.     

Classification of upper limb disability levels of children with spastic unilateral cerebral palsy using <Emphasis Type="Italic">K</Emphasis>-means algorithm

Treatment for cerebral palsy depends upon the severity of the child’s condition and requires knowledge about upper limb disability. The aim of this study was to develop a systematic quantitative classification method of the upper limb disability levels for children with spastic unilateral cerebral palsy based on upper limb movements and muscle activation. Thirteen children with spastic unilateral cerebral palsy and six typically developing children participated in this study. Patients were matched on age and manual ability classification system levels I to III. Twenty-three kinematic and electromyographic variables were collected from two tasks. Discriminative analysis and K-means clustering algorithm were applied using 23 kinematic and EMG variables of each participant. Among the 23 kinematic and electromyographic variables, only two variables containing the most relevant information for the prediction of the four levels of severity of spastic unilateral cerebral palsy, which are fixed by manual ability classification system, were identified by discriminant analysis: (1) the Falconer index (CAI _E ) which represents the ratio of biceps to triceps brachii activity during extension and (2) the maximal angle extension (θ _{Extension,max}). A good correlation (Kendall Rank correlation coefficient = ?0.53, p = 0.01) was found between levels fixed by manual ability classification system and the obtained classes. These findings suggest that the cost and effort needed to assess and characterize the disability level of a child can be further reduced.     

An automated behavior analysis system for freely moving rodents using depth image

A rodent behavior analysis system is presented, capable of automated tracking, pose estimation, and recognition of nine behaviors in freely moving animals. The system tracks three key points on the rodent body (nose, center of body, and base of tail) to estimate its pose and head rotation angle in real time. A support vector machine (SVM)-based model, including label optimization steps, is trained to classify on a frame-by-frame basis: resting, walking, bending, grooming, sniffing, rearing supported, rearing unsupported, micro-movements, and “other” behaviors. Compared to conventional red-green-blue (RGB) camera-based methods, the proposed system operates on 3D depth images provided by the Kinect infrared (IR) camera, enabling stable performance regardless of lighting conditions and animal color contrast with the background. This is particularly beneficial for monitoring nocturnal animals’ behavior. 3D features are designed to be extracted directly from the depth stream and combined with contour-based 2D features to further improve recognition accuracies. The system is validated on three freely behaving rats for 168 min in total. The behavior recognition model achieved a cross-validation accuracy of 86.8% on the rat used for training and accuracies of 82.1 and 83% on the other two “testing” rats. The automated head angle estimation aided by behavior recognition resulted in 0.76 correlation with human expert annotation.

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Graphical abstract Top view of a rat freely behaving in a standard homecage, captured by Kinect-v2 sensors. The depth image is used for constructing a 3D topography of the animal for pose estimation, behavior recognition, and head angle calculation. Results of the processed data are displayed on the user interface in various forms.

     

A new parameter tuning approach for enhanced motor imagery EEG signal classification

A brain-computer interface (BCI) system allows direct communication between the brain and the external world. Common spatial pattern (CSP) has been used effectively for feature extraction of data used in BCI systems. However, many studies show that the performance of a BCI system using CSP largely depends on the filter parameters. The filter parameters that yield most discriminating information vary from subject to subject and manually tuning of the filter parameters is a difficult and time-consuming exercise. In this paper, we propose a new automated filter tuning approach for motor imagery electroencephalography (EEG) signal classification, which automatically and flexibly finds the filter parameters for optimal performance. We have evaluated the performance of our proposed method on two public benchmark datasets. Compared to the existing conventional CSP approach, our method reduces the average classification error rate by 2.89% and 3.61% for BCI Competition III dataset IVa and BCI Competition IV dataset I, respectively. Moreover, our proposed approach also achieved lowest average classification error rate compared to state-of-the-art methods studied in this paper. Thus, our proposed method can be potentially used for developing improved BCI systems, which can assist people with disabilities to recover their environmental control. It can also be used for enhanced disease recognition such as epileptic seizure detection using EEG signals.

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Graphical abstract ?

     

EAACI Position paper on the standardization of nasal allergen challenges

Nasal allergen challenge (NAC) is an important tool to diagnose allergic rhinitis. In daily clinical routine, experimentally, or when measuring therapeutic success clinically, nasal allergen challenge is fundamental. It is further one of the key diagnostic tools when initiating specific allergen immunotherapy. So far, national recommendations offered guidance on its execution; however, international divergence left many questions unanswered. These differences in the literature caused EAACI to initiate a task force to answer unmet needs and find a consensus in executing nasal allergen challenge. On the basis of a systematic review containing nasal allergen challenges of the past years, task force members reviewed evidence, discussed open issues, and studied variations of several subjective and objective assessment parameters to propose a standardized way of a nasal allergen challenge procedure in clinical practice. Besides an update on indications, contraindications, and preparations for the test procedure, main recommendations are a bilaterally challenge with standardized allergens, with a spray device offering 0.1 mL per nostril. A systematic catalogue for positivity criteria is given for the variety of established subjective and objective assessment methods as well as a schedule for the challenge procedure. The task force recommends a unified protocol for NAC for daily clinical practice, aiming at eliminating the previous difficulty of comparing NAC results due to unmet needs.     

Adaptive step goals and rewards: a longitudinal growth model of daily steps for a smartphone-based walking intervention

Adaptive interventions are an emerging class of behavioral interventions that allow for individualized tailoring of intervention components over time to a person’s evolving needs. The purpose of this study was to evaluate an adaptive step goal + reward intervention, grounded in Social Cognitive Theory delivered via a smartphone application (Just Walk), using a mixed modeling approach. Participants (N = 20) were overweight (mean BMI = 33.8 ± 6.82 kg/m²), sedentary adults (90% female) interested in participating in a 14-week walking intervention. All participants received a Fitbit Zip that automatically synced with Just Walk to track daily steps. Step goals and expected points were delivered through the app every morning and were designed using a pseudo-random multisine algorithm that was a function of each participant’s median baseline steps. Self-report measures were also collected each morning and evening via daily surveys administered through the app. The linear mixed effects model showed that, on average, participants significantly increased their daily steps by 2650 (t = 8.25, p < 0.01) from baseline to intervention completion. A non-linear model with a quadratic time variable indicated an inflection point for increasing steps near the midpoint of the intervention and this effect was significant (t² = ?247, t = ?5.01, p < 0.001). An adaptive step goal + rewards intervention using a smartphone app appears to be a feasible approach for increasing walking behavior in overweight adults. App satisfaction was high and participants enjoyed receiving variable goals each day. Future mHealth studies should consider the use of adaptive step goals + rewards in conjunction with other intervention components for increasing physical activity.     

Racial (vs. self) affirmation as a protective mechanism against the effects of racial exclusion on negative affect and substance use vulnerability among black young adults

Affirming one’s racial identity may help protect against the harmful effects of racial exclusion on substance use cognitions. This study examined whether racial versus self-affirmation (vs. no affirmation) buffers against the effects of racial exclusion on substance use willingness and substance use word associations in Black young adults. It also examined anger as a potential mediator of these effects. After being included, or racially excluded by White peers, participants were assigned to a writing task: self-affirmation, racial-affirmation, or describing their sleep routine (neutral). Racial exclusion predicted greater perceived discrimination and anger. Excluded participants who engaged in racial-affirmation reported reduced perceived discrimination, anger, and fewer substance use cognitions compared to the neutral writing group. This relation between racial-affirmation and lower substance use willingness was mediated by reduced perceived discrimination and anger. Findings suggest racial-affirmation is protective against racial exclusion and, more generally, that ethnic based approaches to minority substance use prevention may have particular potential.     

Developing a typology of patient-generated behavioral goals for cognitive behavioral therapy for chronic pain (CBT-CP): classification and predicting outcomes

Patient-generated treatment goals describe what patients value, yet the content of these goals, and the relationship among goal types, goal accomplishment, and treatment outcomes has received little examination. We used inductive sorting to categorize patient-generated goals made by 147 adults receiving cognitive-behavioral therapy for chronic pain. The resulting goal categories were: Physical Activity (29.0%), Functional Status (24.6%), Wellness (16.3%), Recreational Activities (11.3%), House/Yard Work (9.7%), Socializing (7.1%), and Work/School (2.0%). Next, we examined associations between number of goals by category, goal accomplishment, and clinically meaningful improvements in pain-related interference, pain intensity and depressive symptoms. Improvement in all outcome domains was related to goal accomplishment. Additionally, depressive symptoms were related to number of Physical Activity, House/Yard Work, Recreational Activities, and Wellness goals, whereas improved pain-intensity was significantly related to House/Yard Work. Classifying patient-generated goals facilitates investigation of the relationships among goal type, goal accomplishment and treatment outcomes.     

Demographic,clinical, dispositional,and social-environmental characteristics associated with psychological response to a false positive ovarian cancer screening test: a longitudinal study

Cancer screening can facilitate early detection that improves survival, but also can identify an abnormal finding that is not malignant and deemed benign. While such false positive (FP) results can impact a variety of psychological outcomes, little is known about demographic, clinical, dispositional, and social-environmental characteristics associated with psychological outcomes after a FP result. Women participating in an ovarian cancer (OC) screening program and experiencing a FP screening test result (n = 375) completed assessments at baseline and 4-months. Results indicated greater social constraint and less education were linked to greater OC-specific distress at both assessments. Short-term predictors included less optimism and no previous abnormal test, while longer-term predictors were fewer previous screens and the interaction between OC family history and monitoring coping style. Younger age, less education, less optimism, greater social constraint, and family history of OC were associated with greater perceptions of OC risk. Brief interventions prior to screening may minimize the negative impact of a false positive result and not interfere with compliant participation in screening programs.     

Vitamin D deficiency and depressive symptoms in pregnancy are associated with adverse perinatal outcomes

Prenatal vitamin D deficiency and prenatal depression are both separately associated with adverse perinatal outcomes; however, to our knowledge no studies have investigated the effects of having both risk factors. Our objective was to determine to what extent vitamin D deficiency predicts adverse perinatal outcomes and whether elevated depressive symptoms in pregnancy places women at additional increased risk. This study was a secondary data analysis of prospective data collected from a cohort of pregnant women (N?=?101) in an obstetric clinic of a large medical center. Maternal vitamin D deficiency (serum 25(OH)D?≤?20 ng/ml) and depressive symptoms (Edinburgh Postnatal Depression Scale, EPDS) were assessed in early pregnancy. A composite of four adverse perinatal outcomes (low birth weight, preterm birth, small-for-gestational age, and preeclampsia) were abstracted from medical charts. Nineteen of the 101 women had one or more adverse perinatal outcome and 84% with an adverse outcome (16/19) were not White. Both prenatal and time of delivery vitamin D deficiency were associated with developing an adverse outcome compared to those vitamin D sufficient (prenatal relative risk 3.43; 95% CI 1.60–7.34, p?=?0.004; delivery time relative risk 5.14, 95% CI 2.68–9.86, p?=?0.004). These both remained significant after adjusting for BMI. A higher rate of adverse outcome was found when women had both prenatal vitamin D deficiency and elevated depressive symptoms (EPDS?≥?10). Sixty percent with both risk factors had an adverse perinatal outcome versus 17% with only one or neither risk factor (relative risk 3.60; 95% CI 1.55–8.38, p?=?0.045), worthy of investigation with larger samples. Together, prenatal vitamin D deficiency and elevated depressive symptoms in pregnancy may increase risk for adverse perinatal outcomes, especially in racial minorities. Obstetric providers should consider routine prenatal depression screening. The impact of vitamin D supplementation to reduce risk for adverse perinatal outcomes should be studied in prospective trials. Our results suggest that supplementation early in pregnancy might be especially beneficial for depressed women.