Comparative Study of Perforated RF MEMS Switch

AbstractMEMS are the Micro Electronic mechanical system or in general terms it is also known as Micro electronic mechanical switch. MEMS have classified in two types of switch that is series switch and shunt switch .The cantilever is a series type switch whereas the fixed- fixed beam is shunt type switch. Fixed- Fixed beam is the element that is fixed at both anchor ends. The electrostatic actuation process occurs on the switch due to which switch deflects from its original position. The stiction problem occurs in MEMS switches which have been reduced by the proposed design. The perforation is used to reduce the squeeze film damping by decreasing the mass of the switch. As the voltage increases the switch moves to downward z-direction .The displacement is produced in the switch as direction of movement is towards negative z-axis. When the beam contacts with electrode, pull in voltage is achieved. This paper explores the perforation and meander concept with Fixed -fixed switch, which increases the flexibility, low actuation voltage and switching speed. The various types of perforations provide discrete displacement corresponding to voltage. In this paper we represent the design and simulation of Fixed-Fixed switch using perforation of size 2μm-5μm. The electrostatic actuation mechanism is applied on the Fixed-fixed switch which has a serpentine meanders and perforation at different voltages. The switch is designed and simulated by using COMSOL®MULTIPHYSICS 4.3b software

Efficacy and safety of various drugs used for the treatment of nonneurogenic lower urinary tract symptoms in tertiary care hospital

Background: Lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are common in elder men. Previously surgical treatment was mainstay of treatment of BPH. But now number of drugs alone or combined are clinically used for this disorder. Primary aim was to study the prescribing pattern of different drug therapies and their role in treating LUTS/BPH by evaluating their efficacy and safety in tertiary health care centre.Methods: An observational study including 78 male patients ≥45 years, newly diagnosed with LUTS from April 2014 to May 2015. Patients were followed up every 4 weeks for 3 months after the drug has been prescribed. Efficacy assessment was done on basis of change in IPSS score over 12 weeks. Data was expressed in percentage and Mean ±SD.Results: Mean age of Patients was 64.94 years. Alpha blockers are mainstay prescribed drug either as monotherapy (48.7%) or with 5 alpha reductase inhibitor-dutasteride (38.4%) and with antimuscarinic –Tolterodene (12.8%). Among alpha blockers Tamsulosin (58.97%) was most commonly prescribed, followed by Silodosin (20.5%) and Alfuzosin (20.5%). All drug treatment results in significant improvement with dizziness being the most common adverse event. A subgroup analysis in symptoms was done comparing alpha blockers. All alpha blockers have near about similar efficacy with no significant difference.Conclusions: Alpha blockers are main drugs prescribed in management of LUTS/BPH with near about similar efficacy of all alpha blockers

Effects of combined gate and ohmic recess on GaN HEMTs

AlGaN/GaN, because of their superior material properties, are most suitable semiconductor material for High Electron Mobility Transistors (HEMTs). In this work we investigated the hidden physics behind these materials and studied the effect of recess technology in AlGaN/GaN HEMTs. The device under investigation is simulated for different recess depth using Silvaco-Atlas TCAD. Recess technology improves the performance of AlGaN/GaN HEMTs. We considered three kinds of recess technology gate, ohmic and combination of gate and ohmic. Gate recess improves transconductance gm but it reduces the drain current Id of the device under investigation. Ohmic recess improves the transconductance gm but it introduces leakage current Ig in the device. In order to use AlGaN/GaN for high voltage operation, both the transconductance and the drain current should be reasonably high which is obtained by combining both gate and ohmic recess technologies. A good balance in transconductance and drain current is achieved by combining both gate and ohmic recess technologies without any leakage current

Role of cardiac renin angiotensin system in ischemia reperfusion injury and preconditioning of heart

Cardio-vascular diseases are the leading cause of morbidity and mortality. Ischemia is a state of oxygen deprivation in tissues, whereas reperfusion is restoration of blood flow in ischemic tissues. Myocardial damage of tissue during reperfusion after ischemic insult is known as myocardial ischemia–reperfusion (I/R) injury. It induces damage to cardiac muscle via increasing expression of oxygen, sodium and calcium ions which are responsible in the activation of proteases and cell death. Heart renin angiotensin system (RAS) plays an important role in the myocardial ischemia and reperfusion injury. Angiotensin (1–7) is responsible for vasodilation and angiotensin II for vasoconstriction. Here-in we reviewed how myocardial I/R injury sets in by up-regulation of angiotensin II that leads to increased infarct size, which can be reduced by the use of ACE inhibitors, ACE2 activators and angiotensin II antagonist

Efficacy and safety of various drugs used for the treatment of nonneurogenic lower urinary tract symptoms in tertiary care hospital

Background: Lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are common in elder men. Previously surgical treatment was mainstay of treatment of BPH. But now number of drugs alone or combined are clinically used for this disorder. Primary aim was to study the prescribing pattern of different drug therapies and their role in treating LUTS/BPH by evaluating their efficacy and safety in tertiary health care centre. Methods: An observational study including 78 male patients and #8805;45 years, newly diagnosed with LUTS from April 2014 to May 2015. Patients were followed up every 4 weeks for 3 months after the drug has been prescribed. Efficacy assessment was done on basis of change in IPSS score over 12 weeks. Data was expressed in percentage and Mean +/-SD. Results: Mean age of Patients was 64.94 years. Alpha blockers are mainstay prescribed drug either as monotherapy (48.7%) or with 5 alpha reductase inhibitor-dutasteride (38.4%) and with antimuscarinic and ndash;Tolterodene (12.8%). Among alpha blockers Tamsulosin (58.97%) was most commonly prescribed, followed by Silodosin (20.5%) and Alfuzosin (20.5%). All drug treatment results in significant improvement with dizziness being the most common adverse event. A subgroup analysis in symptoms was done comparing alpha blockers. All alpha blockers have near about similar efficacy with no significant difference. Conclusions: Alpha blockers are main drugs prescribed in management of LUTS/BPH with near about similar efficacy of all alpha blockers. [Int J Basic Clin Pharmacol 2016; 5(2.000): 517-522

Biodegradable and electrically conductive melanin‐Poly (3‐hydroxybutyrate) 3D fibrous scaffolds for neural tissue engineering applications

Due to the severity of peripheral nerve and spinal cord injuries, treatment options for patients are limited. In this context, biomaterials designed to promote regeneration and reinstate the lost function are being explored. Such biomaterials should be able to mimic the biological, chemical, and physical cues of the extracellular matrix for maximum effectiveness as therapeutic agents. Development of biomaterials with desirable physical, chemical, and electrical properties, however, has proven challenging. Here, we propose a novel biomaterial formulation achieved by blending the pigment melanin and the natural polymer Poly (3-hydroxybutyrate). Physio-chemical measurements of electrospun fibers revealed a feature rich surface nano-topography, a semiconducting-nature and brain-tissue-like poroviscoelastic properties. Resulting fibers improved cell adhesion and growth of mouse sensory and motor neurons, without any observable toxicity. Further, the presence of polar functional groups positively affected the kinetics of fibers degradation at a pH (∼7.4) comparable to that of body fluids. Thus, melanin-PHB blended scaffolds were found to be physio-chemically, electrically, and biologically compatible with neural tissues and could be used as a regenerative modality for neural tissue injuries

Exploring the role of ChatGPT in patient care (diagnosis and treatment) and medical research: A systematic review

Background: ChatGPT is an artificial intelligence based tool developed by OpenAI (California, USA). This systematic review examines the potential of ChatGPT in patient care and its role in medical research. Methods: The systematic review was done according to the PRISMA guidelines. Embase, Scopus, PubMed and Google Scholar data bases were searched. We also searched preprint data bases. Our search was aimed to identify all kinds of publications, without any restrictions, on ChatGPT and its application in medical research, medical publishing and patient care. We used search term "ChatGPT". We reviewed all kinds of publications including original articles, reviews, editorial/ commentaries, and even letter to the editor. Each selected records were analysed using ChatGPT and responses generated were compiled in a table. The word table was transformed in to a PDF and was further analysed using ChatPDF. Results: We reviewed full texts of 118 articles. ChatGPT can assist with patient enquiries, note writing, decision-making, trial enrolment, data management, decision support, research support, and patient education. But the solutions it offers are usually insufficient and contradictory, raising questions about their originality, privacy, correctness, bias, and legality. Due to its lack of human-like qualities, ChatGPT’s legitimacy as an author is questioned when used for academic writing. ChatGPT generated contents have concerns with bias and possible plagiarism. Conclusion: Although it can help with patient treatment and research, there are issues with accuracy, authorship, and bias. ChatGPT can serve as a "clinical assistant" and be a help in research and scholarly writing

Fragmented narrow QRS complex: Predictor of left ventricular dyssynchrony in non-ischemic dilated cardiomyopathy

Background: Cardiac resynchronization therapy is an important therapeutic modality in drug refractory symptomatic patients of heart failure with wide QRS (≥120 ms) on electrocardiogram. However, wide QRS (considered as a marker of electrical dyssynchrony) occurs in only 30% of heart failure patients, making majority of drug refractory heart failure patients ineligible for resynchronization therapy. Significant numbers of patients with narrow QRS have echocardiographic evidence of left ventricular dyssynchrony. However, there is sparse data about additional features on the surface ECG which can predict intraventricular dyssynchrony. This study was undertaken to assess the utility of fragmented narrow QRS complex to predict significant intraventricular dyssynchrony in symptomatic patients of non-ischemic dilated cardiomyopathy. Method: 100 symptomatic patients of non-ischemic dilated cardiomyopathy with narrow QRS complexes (50 each with fragmented and normal QRS) were recruited. Tissue Doppler imaging was used to assess intraventricular dyssynchrony as per ‘Yu index’. Results: 78% patients (n = 39) in fQRS complex group and 14% (n = 7) in normal QRS complex group had significant intraventricular dyssynchrony (χ2 = 20.61; p < 0.000005). fQRS complexes had 84.78% sensitivity, 79.62% specificity, a positive predictive value of 78% and negative predictive value of 86% to detect intraventricular dyssynchrony. fQRS also had sensitivity and specificity of 93% and 90% respectively to localize the dyssynchronous segment. Conclusion: fQRS is a marker of electrical dyssynchrony, which results in significant intraventricular dyssynchrony in patients of non-ischemic dilated cardiomyopathy and a narrow QRS interval. fQRS localizes the dyssynchronous segment and might be useful in identifying patients who can benefit from cardiac resynchronization therapy