Modeling and simulations of diphasic composites for development of high energy density dielectrics

This research is focused on diphasic dielectric composites for high energy density storage applications in pulsed power and power distribution systems. Composite materials are particularly attractive because they can synergistically combine high permittivity with high breakdown strength of the individual phases. Energy density, which captures permittivity and dielectric breakdown strength as vital material parameters, dominates this research challenge. Avenues for increasing the effective permittivity and breakdown strength may be found by gaining fundamental understanding of the response of diphasic dielectrics to an applied electric field. Improved understanding of these characteristics will ultimately lead to dielectrics with increased energy storage densities. Current research is centered on improving the understanding of dielectric composite response through analytical modeling, numerical simulations and experimental work --Introduction, page 18

Survey Paper on Emotion Recognition

Facial expressions give important information about emotions of a person. Understanding facial expressions accurately is one of the challenging tasks for interpersonal relationships. Automatic emotion detection using facial expressions recognition is now a main area of interest within various fields such as computer science, medicine, and psychology. HCI research communities also use automated facial expression recognition system for better results. Various feature extraction techniques have been developed for recognition of expressions from static images as well as real time videos. This paper provides a review of research work carried out and published in the field of facial expression recognition and various techniques used for facial expression recognition

Epidemiology, diagnosis and management of patients with biliary dyskinesia and sphincter of Oddi dysfunction: a survey of Indian gastroenterologists

Background: A cross-sectional, physician-based survey was conducted to address the relative lack of data on the awareness about and management of biliary dyskinesia and sphincter of Oddi dysfunction among Indian gastroenterologists. Methods: A structured questionnaire containing questions on epidemiology, etiology, clinical presentation, diagnostic investigations, prognosis and management was used. Physician responses were analyzed as descriptive statistics and reported as frequency and percentages. Results: A total 146 gastroenterologists across 137 cities participated in the survey. Majority (76.0%) of physicians stated that <10% of their patients with cholecystitis get diagnosed with BD, while 84.7% stated that <25% of patients with BD have SOD. SOD and BD were reported to be common in females <50 years. Patients recovering from major surgeries/stroke/heart attack/sepsis/extensive trauma were identified by 53.0% of physicians to be at risk for BD. Majority of physicians (69.4%) reported that irritable bowel syndrome (IBS) was a major risk factor for SOD. Cholescintigraphy and hepatobiliary scintigraphy were investigations of choice for BD and SOD according to 55.5% and 33.6% of physicians, respectively. Sepsis was identified as a frequent complication of BD (45.2%). Laparoscopic cholecystectomy was identified by 64.4% participants to result in partial resolution of symptoms in many patients. Calcium channel blockers and antispasmodics were preferred by 55.9% and 30.8% physicians for functional gall bladder disorder, respectively. IBS was the most common indication for prescribing the antispasmodic pinaverium, with the primary objective of pain relief. Conclusions: Findings from this survey provide insights for further research on BD and SOD in India

Clinicoradiological correlation in birth asphyxia

Background: Hypoxic Ischemic Encephalopathy (HIE) is the most dreaded neurological disease of the new-born. Assessment of severity of HIE would help proper parent counseling and early institution of stimulation therapy for better development of the infant.Methods: This study was conducted between December 2012 and May 2014. 37 term neonates with perinatal asphyxia were the subjects. The cranial ultrasound, EEG and MRI findings of these babies are analysed and correlated with each other and with clinical staging and the neurological condition of the babies at discharge.Results: Among the 37 neonates, 21 were of HIE stage 2 and 16 were of stage 3. Sensitivity of EEG in detecting abnormality in the neurological condition according to our study is 76.9%, specificity 87.5%, positive predictive value 76.9%, negative predictive value 87.5%. Sensitivity of severe pattern of injury in MRI brain in detecting abnormality in neurological condition according to our study is 76.9%, specificity 91.6%, positive predictive value 83.3%, negative predictive value 88%. Involvement of both basal ganglia and cortex in MRI brain had statistically significant correlation with abnormal neurological condition at discharge in our study (P = 0.04).Conclusion: An abnormal EEG and MRI brain in a term new-born with Hypoxic Ischemic Encephalopathy (HIE) is associated with poor neurological outcome. Involvement of basal ganglia/thalamus and cortex together in the MRI are predictors of abnormal outcome.

A molecular dynamics study of the interface temperature in ultrasonic metal welding

In this study, mechanical and thermal behavior of the mating interface during ultrasonic metal welding is investigated using molecular dynamics (MD) simulations. In ultrasonic welding process, the reciprocating motion of the sonotrode together with the application of the external pressure on the mating parts are the sources of friction heat generation, high temperature gradient at the interface and plastic deformations. The rapid process of ultrasonic welding, which takes a few seconds at the longest, involves coupled mechanical and thermal processes. Therefore, MD simulations have been employed to elucidate the nano-mechanics of this complex coupled process within the picosecond timescale. To this end, the atomic scale simulations of the microstructure at and in the vicinity of the mating interface have been carried out. This contribution addresses the interactive effects of the process parameters on the interface temperature evolution and the diffusion behavior of the interface atoms at the atomic scale. The results of this work are compared to the results from macro scale investigations

Comparison of Extended Nasolabial Flap Versus Buccal Fat Pad Graft in the Surgical Management of Oral Submucous Fibrosis - A Prospective Study.

Background, aim and objectives Oral submucous fibrosis is a chronic progressive premalignant condition, characterized by gradually increasing fibrosis of sub mucosa resulting in trismus thereby, limiting mouth opening. Various surgical modalities have been tried in the surgical management, but each has its own limitations. In the present study, extended nasolabial flap and buccal fat pad graft have been used for reconstruction after release of fibrosis. These two methods have been compared and assessed for their role in improving the mouth opening post operatively. Methods The study group consisted of 8 patients with bilateral clinically and histopathologically proven cases of oral submucous fibrosis. Group 1 (extended nasolabial flap) was compared with group 2 (buccal fat pad graft) post operatively for mouth opening up to 3 months follow up. Results In the present study, buccal fat pad graft proved to give better results as the interposition material as it has good patient acceptance, rapid epithelization, minimal donor site morbidity and minimal intra and postoperative complications. Interpretation & conclusion Based on the present study, use of buccal fat pad graft following excision of fibrotic bands, in the management of oral submucous fibrosis gave better results with respect to postoperative mouth opening

Analysis of Spatial Performance of Meteorological Drought Indices

Meteorological drought indices are commonly calculated from climatic stations that have long-term historical data and then converted to a regular grid using spatial interpolation methods. The gridded drought indices are mapped to aid decision making by policy makers and the general public. This study analyzes the spatial performance of interpolation methods for meteorological drought indices in the United States based on data from the Co-operative Observer Network (COOP) and United States Historical Climatology Network (USHCN) for different months, climatic regions and years. An error analysis was performed using cross-validation and the results were compared for the 9 climate regions that comprise the United States. Errors are generally higher in regions and months dominated by convective precipitation. Errors are also higher in regions like the western United States that are dominated by mountainous terrain. Higher errors are consistently observed in the southeastern U.S. especially in Florida. Interpolation errors are generally higher in the summer than winter. The accuracy of different drought indices was also compared. The Standardized Precipitation and Evapotranspiration Index (SPEI) tends to have lower errors than Standardized Precipitation Index (SPI) in seasons with significant convective precipitation. This is likely because SPEI uses both precipitation and temperature data in its calculation, whereas SPI is based solely on precipitation. There are also variations in interpolation accuracy based on the network that is used. In general, COOP is more accurate than USHCN because the COOP network has a higher density of stations. USHCN is a subset of the COOP network that is comprised of high quality stations that have a long and complete record. However the difference in accuracy is not as significant as the difference in spatial density between the two networks. For multiscalar SPI, USHCN performs better than COOP because the stations tend to have a longer record. The ordinary kriging method (with optimal function fitting) performed better than Inverse Distance Weighted (IDW) methods (power parameters 2.0 and 2.5) in all cases and therefore it is recommended for interpolating drought indices. However, ordinary kriging only provided a statistically significant improvement in accuracy for the Palmer Drought Severity Index (PDSI) with the COOP network. Therefore it can be concluded that IDW is a reasonable method for interpolating drought indices, but optimal ordinary kriging provides some improvement in accuracy. The most significant factor affecting the spatial accuracy of drought indices is seasonality (precipitation climatology) and this holds true for almost all the regions of U.S. for 1-month SPI and SPEI. The high-quality USHCN network gives better interpolation accuracy with 6-, 9- and 12-month SPI and variation in errors amongst the different SPI time scales is minimal. The difference between networks is also significant for PDSI. Although the absolute magnitude of the differences between interpolation with COOP and USHCN are small, the accuracy of interpolation with COOP is much more spatially variable than with USHCN

Analysis of Spatial Performance of Meteorological Drought Indices

Meteorological drought indices are commonly calculated from climatic stations that have long-term historical data and then converted to a regular grid using spatial interpolation methods. The gridded drought indices are mapped to aid decision making by policy makers and the general public. This study analyzes the spatial performance of interpolation methods for meteorological drought indices in the United States based on data from the Co-operative Observer Network (COOP) and United States Historical Climatology Network (USHCN) for different months, climatic regions and years. An error analysis was performed using cross-validation and the results were compared for the 9 climate regions that comprise the United States. Errors are generally higher in regions and months dominated by convective precipitation. Errors are also higher in regions like the western United States that are dominated by mountainous terrain. Higher errors are consistently observed in the southeastern U.S. especially in Florida. Interpolation errors are generally higher in the summer than winter. The accuracy of different drought indices was also compared. The Standardized Precipitation and Evapotranspiration Index (SPEI) tends to have lower errors than Standardized Precipitation Index (SPI) in seasons with significant convective precipitation. This is likely because SPEI uses both precipitation and temperature data in its calculation, whereas SPI is based solely on precipitation. There are also variations in interpolation accuracy based on the network that is used. In general, COOP is more accurate than USHCN because the COOP network has a higher density of stations. USHCN is a subset of the COOP network that is comprised of high quality stations that have a long and complete record. However the difference in accuracy is not as significant as the difference in spatial density between the two networks. For multiscalar SPI, USHCN performs better than COOP because the stations tend to have a longer record. The ordinary kriging method (with optimal function fitting) performed better than Inverse Distance Weighted (IDW) methods (power parameters 2.0 and 2.5) in all cases and therefore it is recommended for interpolating drought indices. However, ordinary kriging only provided a statistically significant improvement in accuracy for the Palmer Drought Severity Index (PDSI) with the COOP network. Therefore it can be concluded that IDW is a reasonable method for interpolating drought indices, but optimal ordinary kriging provides some improvement in accuracy. The most significant factor affecting the spatial accuracy of drought indices is seasonality (precipitation climatology) and this holds true for almost all the regions of U.S. for 1-month SPI and SPEI. The high-quality USHCN network gives better interpolation accuracy with 6-, 9- and 12-month SPI and variation in errors amongst the different SPI time scales is minimal. The difference between networks is also significant for PDSI. Although the absolute magnitude of the differences between interpolation with COOP and USHCN are small, the accuracy of interpolation with COOP is much more spatially variable than with USHCN

Analysis of results of huge segmental bone loss of tibia treated with Ilizarov external fixator: our experience in Indian population

Background: Orthopaedic surgeons face challenges in treating complex tibial fractures with bone loss due to complications like infection, repeat surgeries, and patient psychological burden. The Ilizarov external fixator approach offers better clinical and radiological results, addressing these issues. The purpose of this study was to examine the outcome of tibial segmental loss treated with the Iliazrov external fixator. Methods: The study was done between January 2015 to December 2021. It’s a prospective as well as retro-prospective study. The age group of 18-65 years was considered. Patients were monitored monthly, up to nine months post-surgery, or until bone union. Functional and bone outcomes of the patients were evaluated using ASAMI criteria, knee society score, and St. Pierre ankle scoring system. Results: The study included 20 patients, all of them were male and had a mean age of 34.1±10.1. Bone union was achieved in all cases. After ilizarov application, the average bone defect was 82.6±42.9 mm. The final regeneration attained was 75.1±47.5 mm. The average limb length difference was 20.41±6.55 mm after achieving union. Out of 20 patients, 13 and 4 had good and fair ASAMI score, 1, 4, and 13 had fair, good, and excellent knee society score, and17 had fair St. Pierre score and 3 patients were lost to follow-up. Conclusions: Ilizarov technique is an excellent way for treating complicated tibial fractures. The difficulties, challenges, and complications associated with Ilizarov external fixation are negligible compared to the significant difficulties associated with open techniques