Foldable substrates for micro-ultrasonic transducers

Ultrasound has broad range of applications from underwater examination, nondestructive testing of materials and medical diagnosis and treatment. The ultrasonic transducer plays an vital role in determining the resolution, sensitivity, as well as other diagnostic capabilities of an ultrasonic imaging system. Current piezoelectric transducer which dominates the medical field has limited applications compared to the capacitive ultrasonic transducer. The capacitive transducer is easy to fabricate compared to the piezoelectric transducer. In this work, the fabrication of a foldable substrate for a capacitive ultrasonic transducer has been discussed. The foldable substrate was fabricated using an ultrathin silicon wafer which is 50 µm thick by using the principle of polymer shrinkage. It is believed that the foldable substrate can be used in intravascular ultrasound (IVUS) and endoscopic ultrasound (EUS) applications for next generation biomedical imaging

Performance Comparison of Multi Input Capacitor Converter Circuits

This paper analyze the operation of a multi input switched capacitor (MIC) converters using a couple of switches, diodes and capacitors for several levels. With two input sources it is possible to obtain 8 output voltage levels. Here, 5 topologies of switched capacitor circuits namely summation, subtraction, inverting, double and half circuits are simulated and their performances are analyzed. Multi Input Converters have a high regard for multiple renewable energy sources used in smart grid systems, especially for distributed generators. The effects on output voltage with variation in load for different frequencies are also analyzed. Hardware implementation of summation and subtraction circuit is carried out and the results are compared with the simulated result

AUTOMATED SENTIMENT ANALYSIS AN AUTOMATED ANALYSIS OF NEWS FEEDS

This Paper explains the importance of Sentiment Analysis in today\u27s business. Information which is hidden as unstructured data in the Internet can be utilized more efficiently. In this paper we quote an approach which explains the experiment for collection of news data and analyzing the sentiments for those data. The results provide almost accurate analysis outcomes with a few discrepancies. These are also explained and research is in progress towards making an efficient system

Mobile Money: The Effect of Service Quality and Competition on Demand

The use of electronic money transfer through cellular networks (“mobile money") is rapidly increasing in the developing world. The resulting electronic currency ecosystem could improve the lives of the estimated 2 billion people who live on less than $2 a day by facilitating more secure, accessible, and reliable ways to store and transfer money than are currently available. The development of this ecosystem requires a network of agents to conduct cash-for-electronic value transactions and vice versa. This paper estimates the effect of competition and service quality on mobile money demand. In this setting, service quality consists of service reliability (lower stockout and system downtime rates), pricing transparency, and agent expertise. Among our results, we find that agents experience reduced demand for service failures due to stockouts, but not for service failures due to network downtime, suggesting that consumers differentially ascribe responsibility for service failure based on the type of failure they experience. We find that both stockout rate and agent expertise are important competitive dimensions in this setting. Pricing transparency, on the other hand, has a main effect on demand but has no significant interaction with competitive intensity. This paper furthers our understanding of the impact and interaction of quality and competition in service settings, while developing a foundation for the exploration of mobile money by OM scholars

Antibiotics usage, how well we know it? KAP survey among the dentist population in Mumbai

Background: There is a rising concern for antibiotic resistance worldwide, the primary cause of which is overuse and misuse. This study primarily aimed at assessing the knowledge of dental practitioners regarding the current guidelines on use of antibiotics and to identify the shortcomings if any.Methods: Present study was a cross-sectional questionnaire-based study conducted amongst 450 dental practitioners across Mumbai with the help of a self-designed questionnaire. The data was entered into excel sheets and appropriate statistical analysis was done with chi-square test using SPSS version 20.Results: The present study had a response rate of 95%. For the total percentage of patients examined each day that required systemic antibiotics, 36.9% (153) dentists answered 0-5%, followed by 25.3% (105) answered 10-15%. 76.1% (316) dentists came across patients who had self-prescribed antibiotics. 66% (274) dentists had never advised an antibiotic sensitivity/ culture test for their patients. 51.3% (213) dentists came across patients who did not respond to antibiotics. 87.2% (363) dentists were not aware about the ‘AWaRe’ classification of antibiotics given by WHO. 93.3% (383) dentists did not know about antimicrobial stewardship concept.Conclusions: The present study reflected antibiotic overuse and misuse to a certain extent by dental practitioners across Mumbai. Most dentists were unaware about ‘AWaRe’ classification and antimicrobial stewardship. Patient education on ill effects of self-prescription of antibiotics, identification of traits of antibiotic resistance and antibiotic culture tests needs to be prioritized by dentists

Passive flow control in wind turbine blade by geometrical optimization of vortex generator

A wind turbine is a device that converts mechanical energy into electrical energy by its rotary action. In this paper, a wind turbine’s lift and power characteristics are improved by employing a vortex generator as a passive flow control device on the surface of the wind turbine. A triangular vortex generator is used for this study for its simplicity in design and effective results. NACA 4418 airfoil is selected for the conceptual design by BEM (Blade Element Momentum theory), and geometrical modeling is carried out using SOLIDWORKS. Computational analysis of the blade with vortex generators is done using ANSYS CFX, and analysis on a clean blade is verified using Q Blade. The geometrical parameters considered for optimization are chordwise position (xvg), Height (hvg), and Inclination from the baseline(βvg), keeping fixed spacing (svg). By optimizing the design parameters, the lift and power increment is observed alongside a delay in the flow separation point, which agrees with the experimental results. This investigation can be extended to future unconventional shapes such as ogive, vane, and wishbone generators through wind tunnel and field tests

Intraperitoneal rectal perforation presenting as fetal ascites – a rare occurrence

Spontaneous perforation of the rectum presenting as fetal ascites is an extremely rare occurrence. We report the case of an infant where antenatally detected fetal ascites was attributable to intraperitoneal rectal perforation. Investigations directed to identify common causes of this condition did not reveal any aetiology. Patient underwent surgical colostomy formation on day two of life, which was reversed at six weeks of age. We suggest that meconium ascites and peritonitis should be considered as differential diagnoses in fetuses with ascites and, if the neonate requires a laparotomy, the rectal area should be thoroughly inspected to exclude this entity

Experimental and computational strategies for enhancing mass transport and cryopreservation of biological tissues

A bioreactor is a large-scale engineered in vitro device that maintains a 3D arrangement of functioning cells for use in various bioengineering applications. The current work is focused on heat and mass transfer issues related to the bioreactor's performance and applications. Firstly, for bioreactors to achieve high functional output, the cells within its 3D tissues constructs must have adequate supplies of nutrients and gases (O2, CO 2 etc). Among these, O2 transport has been a major challenge since regions of hyperoxia and hypoxia can develop. Hence, in the first phase of this work, an O2 transport based computational model is proposed to help simulate the distribution of O2 through the volume of the 3D tissue constructs under various operational conditions. The advantage of such a predictive model is that it can supply preliminary data, helpful for optimizing O2 delivery to the cells. Secondly, the off the shelf availability of the cells and tissues utilized in the bioreactors is maintained mainly through cryopreservation techniques. In the case of large tissues, cryopreservation success is governed by the cryopreservation protocol used. Therefore, in the second phase of this work, a user friendly computational tool able to predict and compare the effectiveness of various cryopreservation protocols is developed. The computational tool's predictions are briefly validated against experimental results to verify its predictive accuracy. The package is designed to offer a cost effective solution for designing protocol's for cryopreserving 3D tissues and tissue equivalent. Thirdly, with specific relevance to the cryopreservation of liver cells and tissues, it was hypothesized that increased aquaporin (AQP) (integral membrane proteins which aid water transport) expressions on the cellular membrane would improve cellular water transport and thereby improve the cryopreservation efficiency. Experimental results showed increased cell viability following cryopreservation of liver tissues equivalents treated for translocation of AQPs to the cellular membrane, thus confirming the hypothesis to be true. Overall, the computational and experimental strategies proposed in the current work would help enhance heat and mass transport to biological tissues, resulting in potential improvement in the performance of bioreactors and other large scale tissue replacement systems

On the Robustness of Explanations of Deep Neural Network Models: A Survey

Explainability has been widely stated as a cornerstone of the responsible and trustworthy use of machine learning models. With the ubiquitous use of Deep Neural Network (DNN) models expanding to risk-sensitive and safety-critical domains, many methods have been proposed to explain the decisions of these models. Recent years have also seen concerted efforts that have shown how such explanations can be distorted (attacked) by minor input perturbations. While there have been many surveys that review explainability methods themselves, there has been no effort hitherto to assimilate the different methods and metrics proposed to study the robustness of explanations of DNN models. In this work, we present a comprehensive survey of methods that study, understand, attack, and defend explanations of DNN models. We also present a detailed review of different metrics used to evaluate explanation methods, as well as describe attributional attack and defense methods. We conclude with lessons and take-aways for the community towards ensuring robust explanations of DNN model predictions.Comment: Under Review ACM Computing Surveys "Special Issue on Trustworthy AI