Development of a Limb prosthesis by reverse mechanotransduction

Recent developments in the field of limb prosthesis have focused on the use of body signals of the user to generate the desired motion in the prosthesis. Unlike earlier designs, this approach is more effective and less stressful for the amputee. The signals that have been used up till now are EMG signals, EEG signals and neural signals. Another possible source of body signal is the pH value of the neuromuscular junction, which depends upon the ion movements across the muscle tissue. Hence, it is safe to assume that changes in the pH can accurately mimic the intended changes in the amputated limb muscles, and therefore can be used to turn the user’s desired motion into actual motion of the limb prosthesis. In the current model, this is achieved through the means of a pH-to-voltage converter that converts the pH value into voltage that is in turn used to drive the motor. The direction of movement is controlled by a microcontroller-based circuit. Further improvements can be made upon the model presented in this thesis, if the pH values could be more accurately read and employed to determine the direction of the movement of the finger too. Also, attempts can be made to apply the same working principle on more complex models of hand prosthesis, thus producing more applicable results

Surface modification of 316L stainless steel by Sol-Gel method

Medical implants made from 316L stainless steel have been used widely and successfully for various types of dental and orthopaedic implants. It is believed that oxide films covering implant surfaces are of crucial importance for biocompatibility and successful osseo-integration. A uniform TiO2 coating on 316L stainless steel coupons has been prepareds using sols-gel methodology followed by hydrothermals post-treatmentsk. Sol-gel process is one of the best wet chemical routes to deposit the coating with convenient production of required thin films and controlled distribution of pore-size, processed at relatively lower temperature than any other conventional coating methods. Different coating thicknesses have been achieved by coating TiO2 sol-gel on samples having different surface finish. The structure and morphology of thef coatingsr weref analyzedh using optical microscope and X-rayf diffractionh technique. When the samples are observed under optical microscope, the results indicate that TiO2 sol-gel coating on 316l stainless steel is uniform and dense; we can see a crack-free surface. The XRD patterns show different strong peaks of TiO2 coating on the substrate. Bioactivity study of the coated samples is done by dipping them in SBF solution. We observe firmly attached hydroxy apatite layer on the TiO2 coated substrate and XRD patterns show the presence of calcium phosphate which increases the osseo-integration. The surface free energy have been calculated for the steel samples having different surface finish and also the contact angle has been measured. Ground samples show the best characteristics with enhanced roughness

Sediment and carbon accumulation in sub-tropical salt marsh and mangrove habitats of north-eastern coast of Bay of Bengal, Indian Ocean

Researches on salt marsh mangrove habitats as global carbon sink are increasing worldwide. However, uncertainties in measuring carbon sequestration capacity of the vulnerable subtropical South Asian coastal habitat thus obstructing the mapping sediment and carbon accumulation rate of their importance.The present investigation was carried out to assess the sedimentation and carbon accumulation rate in salt marsh and mangrove habitats in the vicinity of Sitakunda coast, Chittagong, Bangladesh. The data indicate that sedimentation rate was 22.76±2.56 mg/cm2/day in mangrove area, 63.52±7.42 mg/cm2/day in lower mangrove area, 97.02±6.64 mg/cm2/day in higher marsh area, 5.91±1.16 mg/cm 2/day in lower marsh area and 9.81±0.03 mg/cm2/day in muddy area. The average sedimentation rate was found 39.82±6.72 mg/cm2/day during the study period. Soil organic matter in the newly deposited sediment was 3.89±1.28%, while 3.57±0.77% in accumulated peat sediment.Organic carbon of the newly deposited sediment was 2.05±0.93% and 1.89±0.55% in accumulated peat sediment. Usually, the organic materials were found higher in the peat soil in the wetland habitat, while lower amount of organic materials are found in the present peat soil. Lower amount of organic materials in peat soil in the study area could probably due to higher utilization of organic materials by aquatic plants. Further, uncertainties remain about sediment and carbon accumulation changes with tidal range, latitude and elevation in study area require long-term spatio-temporal investigation

Size-dependent spinodal and miscibility gaps for intercalation in nano-particles

Using a recently-proposed mathematical model for intercalation dynamics in phase-separating materials [Singh, Ceder, Bazant, Electrochimica Acta 53, 7599 (2008)], we show that the spinodal and miscibility gaps generally shrink as the host particle size decreases to the nano-scale. Our work is motivated by recent experiments on the high-rate Li-ion battery material LiFePO4; this serves as the basis for our examples, but our analysis and conclusions apply to any intercalation material. We describe two general mechanisms for the suppression of phase separation in nano-particles: (i) a classical bulk effect, predicted by the Cahn-Hilliard equation, in which the diffuse phase boundary becomes confined by the particle geometry; and (ii) a novel surface effect, predicted by chemical-potential-dependent reaction kinetics, in which insertion/extraction reactions stabilize composition gradients near surfaces in equilibrium with the local environment. Composition-dependent surface energy and (especially) elastic strain can contribute to these effects but are not required to predict decreased spinodal and miscibility gaps at the nano-scale

Biodiversity of hermit crabs in Odisha, east coast and their distribution in other coastal states of India

385-390Hermit crabs are one among the least studied group of the animal kingdom. The diversity of hermit crabs of entire Odisha coast was studied for the first time. Collected primary data and secondary data were compiled to prepare an updated checklist of hermit crabs of Indian coast. A total of seven species of hermit crabs were recorded during the field surveys along Odisha coast. The compilation of secondary data with present primary data revealed occurrence of 114 species of hermit crabs belonging to 27 genera and six families along the Indian coast. Diogenidae was identified as the dominant family. The diversity of hermit crabs is high in the west coast (73 species) as compared to the east coast (65 species). Maximum species diversity is recorded in Tamil Nadu (53 species), Kerala (50 species) and in Andaman & Nicobar Islands (46 species). Twenty threes species of hermit crabs inhabit the coastal ecosystems of Odisha. The present study also reports the occurrence of Clibanarius infraspinatus for the first time from Odisha thus, extending its distributional range along the Indian coast. Among the reported 114 species, only 61 species are included in GBIF with Indian distribution whereas occurrence data is not available for 11 species and 42 species are not likely distributed along Indian coast. The findings of the present study support the occurrence of 61 species (included in Global Biodiversity Information Facility) along the Indian coast and suggest that the occurrence and distribution of remaining 53 species can be confirmed after conducting extensive field surveys

New Particles Working Group Report of the Snowmass 2013 Community Summer Study

This report summarizes the work of the Energy Frontier New Physics working group of the 2013 Community Summer Study (Snowmass)

Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge

Using a novel electrochemical phase-field model, we question the common belief that LixFePO4 nanoparticles separate into Li-rich and Li-poor phases during battery discharge. For small currents, spinodal decomposition or nucleation leads to moving phase boundaries. Above a critical current density (in the Tafel regime), the spinodal disappears, and particles fill homogeneously, which may explain the superior rate capability and long cycle life of nano-LiFePO4 cathodes.Comment: 27 pages, 8 figure

Inner wellbeing: concept and validation of a new approach to subjective perceptions of wellbeing-India

© The Author(s) 2013. This article is published with open access at Springerlink.com. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This paper describes the conceptual development of a multi-domain, psychosocial model of 'Inner Wellbeing' (IWB) and assesses the construct validity of the scale designed to measure it. IWB expresses what people think and feel they are able to be and do. Drawing together scholarship in wellbeing and international development it is grounded in field research in marginalised, rural communities in the global South. Results from research in India at two points in time (2011 and 2013) are reported. At Time 1 (n = 287), we were unable to confirm an eight-factor, correlated model as distinct yet interrelated domains. However, at Time 2 (n = 335), we were able to confirm a revised, seven-factor correlated model with economic confidence, agency and participation, social connections, close relationships, physical and mental health, competence and self-worth, and values and meaning (five items per domain) as distinct yet interrelated domains. In particular, at Time 2, a seven-factor, correlated model provided a significantly better fit to the data than did a one-factor model.This work is supported by the Economic and Social Research Council/Department for International Development Joint Scheme for Research on International Development (Poverty Alleviation) grant number RES-167-25-0507 ES/H033769/1. Special thanks are due to Chaupal and Gangaram Paikra, Pritam Das, Usha Kujur, Kanti Minjh, Susanna Siddiqui, and Dinesh Tirkey