Magneto Acoustic Spin Hall Oscillators

This paper introduces a novel oscillator that combines the tunability of spin Hall-driven nano oscillators with the high quality factor (Q) of high overtone bulk acoustic wave resonators (HBAR), integrating both reference and tunable oscillators on the same chip with CMOS. In such magneto acoustic spin Hall (MASH) oscillators, voltage oscillations across the magnetic tunnel junction (MTJ) that arise from a spin-orbit torque (SOT) are shaped by the transmission response of the HBAR that acts as a multiple peak-bandpass filter and a delay element due to its large time constant, providing delayed feedback. The filtered voltage oscillations can be fed back to the MTJ via a) strain, b) current, or c) magnetic field. We develop a SPICE-based circuit model by combining experimentally benchmarked models including the stochastic Landau-Lifshitz-Gilbert (sLLG) equation for magnetization dynamics and the Butterworth Van Dyke (BVD) circuit for the HBAR. Using the self-consistent model, we project up to $\sim$ 50X enhancement in the oscillator linewidth with Q reaching up to 52825 at 3 GHz, while preserving the tunability by locking the STNO to the nearest high Q peak of the HBAR. We expect that our results will inspire MEMS-based solutions to spintronic devices by combining attractive features of both fields for a variety of applications

Study of coronary artery calcium by multi-slice spiral CT as a tool for high risk cardiovascular screening

Background: Strong relationship has been demonstrated between the presence of occlusive CAD and coronary artery calcification (CAC) detected at autopsy, fluoroscopy and computed tomography (CT scan). CT scan quantifies the relative burden of CAC deposits as a marker of atherosclerosis. We explored utility of multi-slice spiral CT scan for detection of CAC as a tool for screening in asymptomatic high-risk cases above 40 years of age.Methods: Fifty-eight asymptomatic cardiovascular high-risk cases were included as per selection criteria. Detailed clinical history was recorded in every case regarding age, sex, history of risk factors for CAD like systemic hypertension, diabetes mellitus, smoking and family history of CAD. Every case was evaluated for fasting and postprandial blood sugar and fasting lipid profile. Body mass index (BMI) was calculated. An ECG was also recorded. Coronary artery calcium was estimated in each patient by multi -slice spiral CT scan. Fifty age and gender matched consenting participants were enrolled as controls and comparisons drawn.Results: Out of 58 cases scanned, 41 had no detectable CAC by multi-slice CT scan whereas in 17 cases (29.2%), calcium was detected. Mean CAC score was observed to increase as number of risk factors increased.Conclusions: Multi-slice CT scan is a useful tool for detection of coronary artery calcium (CAC) when utilised for high risk screening in older adults having one or more known cardiovascular risk factors

Deep Reinforcement Learning for Approximate Policy Iteration: Convergence Analysis and a Post-Earthquake Disaster Response Case Study

Approximate Policy Iteration (API) is a Class of Reinforcement Learning (RL) Algorithms that Seek to Solve the Long-Run Discounted Reward Markov Decision Process (MDP), Via the Policy Iteration Paradigm, Without Learning the Transition Model in the Underlying Bellman Equation. Unfortunately, These Algorithms Suffer from a Defect Known as Chattering in Which the Solution (Policy) Delivered in Each Iteration of the Algorithm Oscillates between Improved and Worsened Policies, Leading to Sub-Optimal Behavior. Two Causes for This that Have Been Traced to the Crucial Policy Improvement Step Are: (I) the Inaccuracies in the Policy Improvement Function and (Ii) the Exploration/exploitation Tradeoff Integral to This Step, Which Generates Variability in Performance. Both of These Defects Are Amplified by Simulation Noise. Deep RL Belongs to a Newer Class of Algorithms in Which the Resolution of the Learning Process is Refined Via Mechanisms Such as Experience Replay And/or Deep Neural Networks for Improved Performance. in This Paper, a New Deep Learning Approach is Developed for API Which Employs a More Accurate Policy Improvement Function, Via an Enhanced Resolution Bellman Equation, Thereby Reducing Chattering and Eliminating the Need for Exploration in the Policy Improvement Step. Versions of the New Algorithm for Both the Long-Run Discounted MDP and Semi-MDP Are Presented. Convergence Properties of the New Algorithm Are Studied Mathematically, and a Post-Earthquake Disaster Response Case Study is Employed to Demonstrate Numerically the Algorithm\u27s Efficacy

Evaluation of analgesic and anti-inflammatory activity of Levocetirizine in albino rats

Background: Levocetirizine, the R-enantiomer of Cetirizine has pharmacokinetically and pharmacodynamically favourable characteristics, with rapid onset of action, high bioavailability, high affinity for and occupancy of the H1-receptor, limited distribution, minimal hepatic metabolism together with minimal side effects. Non-steroidal anti-inflammatory drugs (NSAIDs) have been used for many years for analgesic, anti-inflammatory, and more recently in the case of aspirin, antithrombotic purposes. Because of the significant side effect profiles of steroidal and NSAID medications, there is a greater interest in newer compounds such as antihistaminic drugs. This article will consider the potential or otherwise of the reported analgesic and anti-inflammatory effects of levocetirizine to enhance its effectiveness in the treatment of allergic disease with pain.Methods: Albino Wistar rats of either sex weighing 150-250 grams were used. For both Analgesic activity and Anti-inflammatory activity, 4 groups consisting of 6 animals per group were used. Group I: Control: 1% Gum acacia. 2ml/kg, Group II: Standard drug: Diclofenac sodium 4.5mg/kg; Group III: Test Drug 1: Levocetirizine 1mg/kg; Group IV: Test Drugs 2: Levocetirizine 1mg/kg+Diclofenac sodium 4.5mg/kg. Drugs were administered orally. For analgesic activity, Tail clip method and Hot plate method was used. For acute anti-inflammatory activity Carrageenan induced rat paw oedema method was used.Results: Levocetirizine, is found to have significant analgesic activity in rats (1 mg/kg dose) alone and in combination with Diclofenac Sodium in Haffner’s Tail Clip method and Eddy’s Hot Plate Method. Levocetirizine also has got prominent anti-inflammatory activity in acute models evidenced by percentage inhibition of acute rat paw oedema.Conclusions: Levocetirizine possess analgesic and acute anti-inflammatory activity alone and in combination with Diclofenac sodium

MICROTEACHING - A TOOL USED TO IMPROVE TEACHING SKILLS AND TEACHING BEHAVIOR IN POST GRADUATE STUDENTS

Background: Medical teachers most often do not receive a special training in pedagogic techniques. Lack of such training results in ineffectivity of the delivered lecture, communication gap between the teacher and the student, which ends up in lowering the quality of teaching and standard of education. "Micro Teaching" technique is used with the aim of helping budding teachers to sharpen their teaching skills and teaching behaviors. Aims & Objective: To inculcate teaching skills and teaching behaviors in Postgraduate (PG) students and to develop the interest in teaching of PG students. Methodology: It was descriptive longitudinal study on eight first year PG student from various department of our institute. It was a four week study each participant underwent two sessions, in first session 10 minute presentation by participants in front of peer group, followed by peer group feedback on teaching skills, second session two weeks later after incorporating suggestions of first session to see the improvement. After second session participants asked to fill "self-evaluation" forms. Results: After comparing first session with second session results it was found statistically significant improvement in teaching skills and everyone agreed that microteaching helps to improve teaching skills and teaching behaviors, develop interest in teaching and boost confidence. Conclusion: This study has confirmed earlier research findings regarding the benefits of the microteaching technique in assisting individuals to develop their professional competence and confidence. Keywords: Microteaching; Teaching-Learning methods; Teach-re-Teach; Small group teaching

MICROTEACHING - A TOOL USED TO IMPROVE TEACHING SKILLS AND TEACHING BEHAVIOR IN POST GRADUATE STUDENTS

Background: Medical teachers most often do not receive a special training in pedagogic techniques. Lack of such training results in ineffectivity of the delivered lecture, communication gap between the teacher and the student, which ends up in lowering the quality of teaching and standard of education. "Micro Teaching" technique is used with the aim of helping budding teachers to sharpen their teaching skills and teaching behaviors. Aims & Objective: To inculcate teaching skills and teaching behaviors in Postgraduate (PG) students and to develop the interest in teaching of PG students. Methodology: It was descriptive longitudinal study on eight first year PG student from various department of our institute. It was a four week study each participant underwent two sessions, in first session 10 minute presentation by participants in front of peer group, followed by peer group feedback on teaching skills, second session two weeks later after incorporating suggestions of first session to see the improvement. After second session participants asked to fill "self-evaluation" forms. Results: After comparing first session with second session results it was found statistically significant improvement in teaching skills and everyone agreed that microteaching helps to improve teaching skills and teaching behaviors, develop interest in teaching and boost confidence. Conclusion: This study has confirmed earlier research findings regarding the benefits of the microteaching technique in assisting individuals to develop their professional competence and confidence. Keywords: Microteaching; Teaching-Learning methods; Teach-re-Teach; Small group teaching