Security, Privacy and Safety Risk Assessment for Virtual Reality Learning Environment Applications

Social Virtual Reality based Learning Environments (VRLEs) such as vSocial render instructional content in a three-dimensional immersive computer experience for training youth with learning impediments. There are limited prior works that explored attack vulnerability in VR technology, and hence there is a need for systematic frameworks to quantify risks corresponding to security, privacy, and safety (SPS) threats. The SPS threats can adversely impact the educational user experience and hinder delivery of VRLE content. In this paper, we propose a novel risk assessment framework that utilizes attack trees to calculate a risk score for varied VRLE threats with rate and duration of threats as inputs. We compare the impact of a well-constructed attack tree with an adhoc attack tree to study the trade-offs between overheads in managing attack trees, and the cost of risk mitigation when vulnerabilities are identified. We use a vSocial VRLE testbed in a case study to showcase the effectiveness of our framework and demonstrate how a suitable attack tree formalism can result in a more safer, privacy-preserving and secure VRLE system.Comment: Tp appear in the CCNC 2019 Conferenc

Nasogastric tube insertion using conventional versus bubble technique for its confirmation in anesthetized patients: a prospective randomized study

Background: Nasogastric tube insertion and confirmation of its position can be difficult in the anesthetized patient. The purpose of the present study was to compare the bubble technique with the conventional method for confirmation of nasogastric tube placement in these patients. Methods: Two hundred sixty adult patients, aged between 20...70 years, posted for surgeries requiring general anesthesia, tracheal intubation, and a nasogastric tube were enrolled in this study. Patients were randomized into 2 groups: Group B (Bubble group) and Group C (Control group). In Group C, a conventional technique using a lubricated nasogastric tube was positioned through the nostril with head remained neutral. In Group B, 2% lidocaine jelly was added to the proximal end to form a single bubble. The correct placement of the nasogastric tube in the stomach was confirmed by fluoroscopy by an independent observer intraoperatively. Results: The duration of nasogastric tube insertion was 57.2 .. 13.3 seconds in Group B and 59.8 .. 11.9 seconds in Group C (p = 0.111). The confirmation rate of the bubble technique was 76.8% (95% CI: 68.7...83.3), which was significantly better than the conventional method where the confirmation rate was 59.7% (95% CI 50.9...67.9), p < 0.001. When compared to fluoroscopy, bubble technique was found to have a sensitivity of 92.3% (95% CI: 85.6...96.1) with specificity of 81.0% (95% CI: 60.0...92.3), positive predictive value of 96.0% (95% CI: 90.2...98.4), and a moderate negative predictive value of 68.0% (95% CI: 48.4...82.8). Conclusions: The bubble technique of nasogastric tube insertion has a higher confirmation rate in comparison to the conventional technique. Trial Registry Number: Clinical Trial Registry of India (CTRI/2018/09/015864)

Is maternal anemia among tribal women being neglected? A study from Southern Rajasthan

Poor birth outcomes have been linked to maternal anemia. Tribal women are at higher risk of malnutrition and disease due to sociocultural barriers and poor educational status. The data on the prevalence of maternal anemia and its associated factors among pregnant tribal women are limited. A community-based cross-sectional study was conducted among 429 pregnant tribal women for maternal anemia from August 2021 to June 2022. A structured questionnaire was employed to collect sociodemographic data. The prevalence of anemia was 85.7%, with a mean hemoglobin level of 9.21 ± 1.3 g/dL. On applying WHO 2011 anemia criteria for pregnant women, 25.0% had mild anemia, 73.4% had moderate anemia, and 1.6% had severe anemia. The significant factors associated with anemic condition were household condition, monthly income, and husband's occupation. The higher prevalence of anemia among pregnant tribal women is alarming that necessitates a rethinking of health infrastructure and outreach in tribal dominant areas

Butterfly proboscis-inspired tight rolling tapered soft actuators

Liquid crystalline networks have been fashioned into thin films with tapered thicknesses, revealing the possibility of rolling up extremely tightly when triggered thermally or with light. Compared to the often limited bending shown previously in liquid crystal network actuators, these tapered films curl up several hundreds of degrees. Finite element results of simulated functionally graded thin films with tapered thicknesses corroborate well with experimental work

Use of ultrasound-guided preoperative diaphragmatic thickness as a predictor of postoperative weaning failure in recipients and donors scheduled for living donor liver transplant surgery

Background and Objectives: The present study was designed to explore the utility of ultrasound-guided diaphragmatic thickness in the preoperative period in healthy controls scheduled for live-related donor hepatectomy and patients suffering from chronic liver disease scheduled for liver transplantation (LT) and its use as a predictor of postoperative weaning failure. Materials and Methods: This prospective observational study was conducted in a tertiary health care center and 65 adult (18–70 years) participants (30 healthy liver donors and 35 liver transplant recipients) were enrolled for this study. Right diaphragmatic thickness of both donors and recipients was measured by B-mode ultrasound using a 10 MHz linear array transducer in the supine position in the operation theater just before induction of anesthesia. For subgroup analysis of the recipients, we further divided them into two groups – Group 1 (diaphragmatic thickness 2 mm), and comparison was done for duration of mechanical ventilation. Intergroup comparison was made for duration of mechanical ventilation and various other parameters. Results: The sonographic measurement of diaphragm revealed that its thickness is decreased in patients with chronic liver disease patients (2.12 ± 0.54 mm) as compared to healthy donors (3.70 ± 0. 58 mm). On multiple logistic regression, higher duration of mechanical ventilation was associated with diaphragmatic thickness < 2 mm (Group 1 of recipients) (adjusted odds ratio 0.86; 95% confidence interval: 0.75–0.99; P = 0.013) after adjusting for age, gender, and body mass index. Conclusions: Diaphragmatic thickness is decreased in patients with chronic liver disease as compared to healthy liver donors. Preoperative measurement of ultrasound-guided right hemidiaphragm thickness can be used to predict weaning failure in patients undergoing LT. Other studies are needed to confirm these finding on different group of patients

Outcomes of cardiac arrest hospitalizations in patients with obesity with versus without prior bariatric surgery status:A nationwide propensity-matched analysis

Introduction: Prior bariatric surgery (PBS) status in obese patients is thought to curtail the risk of cardiovascular events, but its role in change of outcomes of patients with obesity developing new acute cardiac events such as cardiac arrests (CA) remains largely unknown. Methods: Hospitalizations among adult patients with obesity and CA were identified retrospectively using the National Inpatient Sample (2015 October-2017 December). Propensity-matched analysis (1:1) was performed for sociodemographic/hospital characteristics to identify two cohorts, with (PBS+) or without (PBS-) status. The primary endpoint was in-hospital mortality, and the secondary endpoint was healthcare resource utilization. Results: Both cohorts (n = 1275 each), had patients with comparable age (mean 58 years), with a higher frequency of white (>70 %), females (>60 %), and Medicare enrollees (>40 %). PBS + cohort had lower rates of diabetes (27.8 % vs 36.1 %), hyperlipidemia (33.7 % vs 48.6 %), renal failure (17.3 % vs 22.0 %), chronic pulmonary disease (11.8 % vs 21.2 %) and higher rates of anemias (18.4 % vs 12.2 %), liver disease (5.1 % vs 2.4 %) and alcohol abuse (6.7 % vs 2.4 %) than PBS- cohort (p < 0.05). All-cause mortality (46.3 % vs 45.1 %, p = 0.551) was comparable between the two cohorts. The PBS + cohort was less often transferred routinely (p<0.001) but had a shorter hospital stay (p<0.001) with equivalent hospital charges compared to the PBS- cohort. Conclusions: The PBS status (regardless of chronology) did not increase survival in CA admissions among patients with obesity. Preventive measures are necessary to manage enduring cardiovascular disease risk factors that may limit the advantages of surgery for patients with obesity and aggravate the worse outcomes of future cardiac events

Role of Intravascular Ultrasound in Pulmonary Embolism Patients Undergoing Mechanical Thrombectomy: A Systematic Review

Background: Traditionally, mechanical thrombectomy performed for pulmonary embolism (PE) necessitates the utilization of iodinated contrast. Intravascular ultrasound (IVUS) has been used as a diagnostic and therapeutic modality in the management of acute high and intermediate-risk PE. Recently, with the shortage of contrast supplies and the considerable incidence of contrast-induced acute kidney injury (CI-AKI), other safer and more feasible IVUS methods have become desirable. The purpose of this systematic review was to evaluate the importance of IVUS in patients with PE undergoing thrombectomy. Methods: Medline/PubMed, Embase, Scopus, and Google Scholar were searched for review studies, case reports, and case series. Clinical characteristics, outcomes and the usage of IVUS-guided mechanical thrombectomy during the treatment of acute high and intermediate-risk PE were examined in a descriptive analysis. Results: In this systematic review, we included one prospective study, two case series, and two case reports from July 2019 to May 2023. A total of 39 patients were evaluated; most were female (53.8%). The main presenting symptoms were dyspnea and chest pain (79.5%); three patients (7.9%) presented with syncope, one with shock and one with cardiac arrest. Biomarkers (troponin and BNP) were elevated in 94.6% of patients. Most patients (87.2%) had intermediate-risk PE, and 12.8% had high-risk PE. All patients presented with right-heart strain (RV/LV ratio ≥ 0.9, n = 39). Most patients (56.4%) had bilateral PE. Mechanical thrombectomy was performed using IVUS without contrast utilization in 39.4% of the patients. After the initial learning curve, contrast usage decreased gradually over time. There was a significant decrease in the composite mean arterial pressure immediately following IVUS-guided thrombectomy from 35.1 ± 7.2 to 25.2 ± 8.3 mmHg (p < 0.001). Post-procedure, there was no reported (0%) CI-AKI, no all-cause mortality, no major bleeding, or other adverse events. There was a significant improvement in symptoms and RV function at the mean follow-up. Conclusions: New evidence suggests that IVUS-guided mechanical thrombectomy is safe, with visualization of the thrombus for optimal intervention, and reduces contrast exposure