Model Atmospheres for Low Field Neutron Stars

We compute model atmospheres and emergent spectra for low field (B<10^10 G) neutron stars, using new opacity and equation of state data from the OPAL project. These computations, incorporating improved treatments of flux transport and convective stability, provide spectra for hydrogen, solar abundance and iron atmospheres. We compare our results to high field magnetic atmospheres, available only for hydrogen. An application to apparently thermal flux from the low field millisecond pulsar PSR J0437--4715 shows that H atmospheres fit substantially better than Fe models. We comment on extension to high fields and the implication of these results for neutron star luminosities and radii.Comment: 13 pages, text errors in several formulae corrected for publication, 5 eps figures unchanged; to appear in ApJ, April 10, 199

Ultra low power wearable sleep diagnostic systems

Sleep disorders are studied using sleep study systems called Polysomnography that records several biophysical parameters during sleep. However, these are bulky and are typically located in a medical facility where patient monitoring is costly and quite inefficient. Home-based portable systems solve these problems to an extent but they record only a minimal number of channels due to limited battery life. To surmount this, wearable sleep system are desired which need to be unobtrusive and have long battery life. In this thesis, a novel sleep system architecture is presented that enables the design of an ultra low power sleep diagnostic system. This architecture is capable of extending the recording time to 120 hours in a wearable system which is an order of magnitude improvement over commercial wearable systems that record for about 12 hours. This architecture has in effect reduced the average power consumption of 5-6 mW per channel to less than 500 uW per channel. This has been achieved by eliminating sampled data architecture, reducing the wireless transmission rate and by moving the sleep scoring to the sensors. Further, ultra low power instrumentation amplifiers have been designed to operate in weak inversion region to support this architecture. A 40 dB chopper-stabilised low power instrumentation amplifiers to process EEG were designed and tested to operate from 1.0 V consuming just 3.1 uW for peak mode operation with DC servo loop. A 50 dB non-EEG amplifier continuous-time bandpass amplifier with a consumption of 400 nW was also fabricated and tested. Both the amplifiers achieved a high CMRR and impedance that are critical for wearable systems. Combining these amplifiers with the novel architecture enables the design of an ultra low power sleep recording system. This reduces the size of the battery required and hence enables a truly wearable system.Open Acces

A Short Review of Advances in the Modelling of Blood Rheology and Clot Formation

Several advances have taken place since the early 2000s in the field of blood flow modelling. These advances have been driven by the development of assist devices such as Left Ventricular Assist Devices (LVADs), etc., and by the acceptance of in silico tests for the generation of hypotheses concerning clot formation and lysis. We give an overview of the developments in modelling of blood rheology and clot formation/lysis in the last 10 to 15 years. In blood rheology, advances are increasingly supplemented by flow simulation studies. In clot formation (or coagulation), advances have taken place in both single-scale modeling under quiescent conditions as well as in multi-scale modeling in the presence of flow. The future will possibly see more blood flow simulations in complex geometries and, simultaneously, development and simulation of multi-scale models for clot formation and lysis

Reconstruction of complex distal femur open fracture with distal femoral locking plate and primary autologous free fibular graft

Background: Distal femur fractures are high velocity injuries which accounts for 7-10% of all femoral fractures. These injuries are complex injuries which are difficult to manage. Despite advances in techniques and implants, treatment remains a challenge, in many situations.Methods: We present a retrospective review of 8 cases, involved in high velocity road traffic accident who presented to emergency department at St. John’s Medical College, Bangalore, Karnataka, India between September 2011 to December 2015, with complex open fracture of the distal femur with bone loss. All were managed with initial wound debridement and skeletal traction. Subsequently fractured femur was reconstructed with distal femoral locking plate stabilization, along with autogenous non vascularised fibular graft and cortical-cancellous graft bridging the bone defect. Radiological union, functional outcome measured with Tegner and Lyslom scores, KOOS score and complications were assessed.Results: At average 5 years follow up, all the fractures have united well, with good functional outcome. X-ray showing united fracture with incorporation of the fibular graft. According to Tegner and Lyslom scoring, 6 patients had good rating, 2 had satisfactory rating. Average KOOS score was 82.15. Shortening of 2 cm and 4 cm in couple of patients was the major complication. Conclusions: Delayed primary surgery, using autologous non vascularised free fibular graft in conjunction with a locking compression plate, with autogenous cortico-cancellous graft is an effective, less technically demanding and cost effective means of reconstruction option to manage bone defects in complex open fractures of the distal femur. An overall acceptable results in terms of fracture union, fibular incorporation, adequate restoration of knee motion and early rehabilitation can be expected

EUV/soft x-ray spectra for low B neutron stars

Recent ROSAT and EUVE detections of spin-powered neutron stars suggest that many emit 'thermal' radiation, peaking in the EUV/soft X-ray band. These data constrain the neutron stars' thermal history, but interpretation requires comparison with model atmosphere computations, since emergent spectra depend strongly on the surface composition and magnetic field. As recent opacity computations show substantial change to absorption cross sections at neutron star photospheric conditions, we report here on new model atmosphere computations employing such data. The results are compared with magnetic atmosphere models and applied to PSR J0437-4715, a low field neutron star

Functional outcome of antegrade interlocking intramedullary nailing for humeral shaft fractures

Background: Humeral shaft fractures which account for approximately 1-3% of all fractures and 20% of humeral fractures have potential to cause significant disability in the young which is often temporary and in the old often permanent disability. The use of locked intramedullary nailing for the treatment of humeral shaft fractures is gaining popularity because of its biomechanical and biological advantages.Methods: We present a descriptive retrospective review of 20 consecutive patients with acute humeral shaft fractures treated using an antegrade interlocking nail. Fracture union, functional outcome measured with Constant–Murley shoulder score and American shoulder and elbow surgeons (ASES) shoulder score and complications were assessed.Results: Patient age ranged from 20 to 74 years (average, 36 years) and average follow-up was 30.7 months (range, 12–48 months). There were 13 male patients and 7 female patients. Fracture of the middle third was most common accounting to 80% (16/20) of the fractures. Fracture union was achieved in 90% (18/20) of our cases. 2 patients had nonunion for which secondary surgeries were needed. According to Constant–Murley score, shoulder function was excellent in 70% (14/20) and good in 25% (5/20). Average ASES score was 93.3%. None of the patients had radial nerve palsy postoperatively. Conclusions: Gentle progressive reaming, correct entry point, minimal damage to rotator cuff, properly embedding the tip of the nail, good apposition of fracture fragments, static locking will help make antegrade intramedullary nailing, a dependable solution for the treatment of humeral shaft fractures and in achieving successful union with preserved/good shoulder and elbow function

The World's Biggest Country: India's Demographic Trajectory and it's Impact on Muslims, the Parliament and the Labour Market

India's dynamic population has undergone significant shifts over the years. Recently, surpassing China's total population presents a unique opportunity for growth and development. While facing the challenges of managing a large population, India also grapples with economic and resource-related complexities. Additionally, there are internal challenges stemming from communal differences among religious communities and representation in governance. These factors necessitate well-informed and effective policymaking. To ensure the smooth functioning of this vibrant democracy, it is crucial to focus on economic progress and enhancing quality of life. Understanding key concepts like demographic shifts, variations in age groups, uneven population growth, skill disparities, and resource requirements is paramount for a comprehensive approach. This paper explores various facets of India's population dynamics and addresses the hurdles in achieving sustainable growth and effective governance