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Passive sound source localization (SSL) using time-difference-of-arrival (TDOA) measurements is a non-linear inversion problem. In this paper, a data-driven approach to SSL using TDOA measurements is considered. A neural network (NN) is viewed as an architecture constrained non-linear function, with its parameters learnt from the training data. We consider a three layer neural network with TDOA measurements between pairs of microphones as input features and source location in the Cartesian coordinate system as output. Experimentally, we show that, NN trained even on noise-less TDOA measurements can achieve good performance for noisy TDOA inputs also. These performances are better than the traditional spherical interpolation (SI) method. We show that the NN trained offline using simulated TDOA measurements, performs better than the SI method, on real-life speech signals in a simulated enclosure.

It is well known that when there is a relative motion between the transmitter (source) and receiver, a Doppler shift is observed in the spectral content of the received signal. In this paper, we investigate a scenario where the source signal itself has an innate spectral non-stationarity in addition to the non-stationarity introduced by the source motion relative to the receiver. Using only a single microphone recording, we show that these two kinds of non-stationarities are distinguishable and propose a method of separating them. Towards this, we propose a novel scheme of simulating the signal from a source traversing an arbitrary trajectory. The proposed simulation mechanism employs band-limited interpolation and non-uniform sampling to incorporate an acoustic source generating an arbitrary band-limited signal and moving along an arbitrary trajectory.

Evaluation of ultraviolet B index (UVBI) and its impact on vitamin D synthesis is important. We observed the maximum UVBI between 11 am and 1 pm. There was no increase in serum 25(OH)D levels following sun exposure during winter as the UVBI was significantly low, emphasizing the need for vitamin D supplementation during these months. The amount of vitamin D3 synthesizing UVB irradiation (290–320 nm) reaching the earth’s surface at different altitudes and seasons in different parts of India and it’s impact on vitamin D synthesis has not been well studied. The hourly UVB index (UVBI) from 10 am to 3 pm everyday for 12 months was measured by a solar meter in 4 different zones (North, Northeast, West and South) of the country. To study the impact of sun light exposure on vitamin D synthesis during winter, healthy school children aged 10–15 years were exposed to sunlight for a period of 30 min per day, between 11 am to 12 noon with 10 % body surface area, for 4 weeks. The main outcome measures were serum 25(OH)D, PTH, calcium, phosphate, and alkaline phosphatase levels before and after sun exposure. The mean UVBI was highest between 11 am and 1 pm throughout the year in all locations. The highest UVBI was recorded from the North zone (4.5 ± 2.7 μW/Cm2), while the least was recorded in the Northeast zone (2.1 ± 1.2 μW/Cm2). UVBI readings in the Northeast zone were consistently low throughout the year, while all the other three zones showed significant seasonal fluctuations. Surprisingly, we observed a significant decrease in serum 25(OH)D levels from baseline (6.3 ± 4.6 to 5.1 ± 2.7 ng/mL; p

Event-triggered sampling (ETS) is a new approach towards efficient signal analysis. The goal of ETS need not be only signal reconstruction, but also direct estimation of desired information in the signal by skillful design of event. We show a promise of ETS approach towards better analysis of oscillatory non-stationary signals modeled by a time-varying sinusoid, when compared to existing uniform Nyquist-rate sampling based signal processing. We examine samples drawn using ETS, with events as zero-crossing (ZC), level-crossing (LC), and extrema, for additive in-band noise and jitter in detection instant. We find that extrema samples are robust, and also facilitate instantaneous amplitude (IA), and instantaneous frequency (IF) estimation in a time-varying sinusoid. The estimation is proposed solely using extrema samples, and a local polynomial regression based least-squares fitting approach. The proposed approach shows improvement, for noisy signals, over widely used analytic signal, energy separation, and ZC based approaches (which are based on uniform Nyquist-rate sampling based data-acquisition and processing). Further, extrema based ETS in general gives a sub-sampled representation (relative to Nyquist-rate) of a time-varying sinusoid. For the same data-set size captured with extrema based ETS, and uniform sampling, the former gives much better IA and IF estimation. Graphical abstractDisplay Omitted HighlightsAnalysis includes: zero-crossings (ZCs), level-crossings (LCs), and signal extrema.For narrowband nonstationary signals in clean, and additive noise conditions.Performance benefits when compared to traditional approaches.Event-triggered sampling (ETS) can aid in improved analysis of nonstationary signals.

To assess the effect of vitamin D supplementation on parameters of insulin sensitivity/resistance (IS/IR) and insulin secretion in subjects with polycystic ovarian syndrome (PCOS). A prospective double-blind randomized control trial was conducted to assess the effect of vitamin D on insulin kinetics in women with PCOS. The trial was conducted in a tertiary care research hospital. A total of 36 subjects with PCOS, aged 18–35 years, were included in this study. Vitamin D3 4000 IU/day versus placebo was given once a month for 6 months and both groups received metformin. IS (by whole-body IS index or Matsuda index), IR (by homeostasis model assessment IR (HOMA-IR)), and insulin secretion (by insulinogenic index; II30) were the main outcome measures. Secondary outcome included blood pressure (BP), lipid profile, disposition index (DI), and vascular stiffness. Out of 36 subjects who consented, 32 completed the study. Subjects were randomized into two groups: group A (n=15; metformin and vitamin D 4000 IU/day) or group B (n=17; metformin and placebo). Oral glucose tolerance tests with 75 g glucose were carried out at baseline and 6 months after supplementation. Hypovitaminosis D was observed in 93.8% of all subjects with mean serum 25 hydroxy vitamin D level of 7.30±4.45 ng/ml. After 6 months of vitamin D supplementation, there was no significant difference in any of the parameters of IS/IR (area under curve (AUC)–glucose, AUC–insulin, insulin:glucose ratio, HOMA-IR, Matsuda index, insulinogenic index, and DI), II30, and cardiovascular risk factors between the two groups. Supplementation of vitamin D, at a dose of 4000 IU/day for 6 months, did not have any significant effect on parameters of IS/IR and insulin secretion in subjects with PCOS.

Summary Background Frequency of hepatocellular carcinoma (HCC) in hepatic venous outflow tract obstruction (HVOTO) is unclear and risk factors in HVOTO associated with HCC are unknown. Aim To assess the incidence of HCC and to identify risk factors for HCC in primary HVOTO. Methods In the consecutive primary HVOTO patients evaluated between 1989 to 2013, the incidence of HCC among HVOTO was assessed in a retrospective cohort study and identification of the risk factors for HCC in HVOTO patients done by a case–control study. Results Of the 421 HVOTO patients, 8 had HCC at presentation (prevalence 1.9%). Another 8 of the remaining 413 developed HCC during 2076.2 person-years follow-up (mean 5.03 + 4.65 years, range 0.08–20 years). The cumulative incidence of HCC was 3.5% (95% CI 1.28–9.2%) at 10 years. The case–control study included 16 HCC as cases and remaining 405 as controls. Controls were predominantly males (M:F – 230:175), mean age 29 ± 10.3 years. Cases were predominantly females with an older age of 36.2 ± 11.4 years (P

Heat pumps are the most promising technologies to reduce global warming emissions and to more rationally use energy. In this experimental investigation Carbon Dioxide (CO2) was used as refrigerant which is available in nature, eco friendly, economical, non toxic, non flammable and non corrosive. It is The performance evaluation of prototype vapor compression heat pump model was performed and evaluated the different parameters such as LMTD (Logarithmic Mean Temperature Difference), COP (Co-efficient of Performance) and heat transfer rate of condenser. This experiment is carried out by varying water mass flow rate, pressure and evaporator fan speed for two condensers of different dimensional specification. The water in the shell side was heated by absorbing heat from refrigerants in the tube side of condensers by counter flow heat exchanging method. The experimental results indicate fairly good COP with the use of CO2. The advantages of CO2 as refrigerant with zero ODP and minimum GWP.

In this work, we examine the effect of timbre of the signal on auditory source width (ASW). The timbre of the signal is varied as low pass, high pass and band pass filtered white Gaussian noise of different bandwidths. We also study the ASW perception of a time-varying multi-component music signal (violin). Three normal hearing listeners rate the perceptual ASW of these stimuli on a scale of (0–120)% using a MUSHRA-type presentation. The stimuli are presented on a linear loudspeaker array. Amongst noise stimuli, it is found that low pass stimuli of cut-off frequency of 250 Hz gives the widest ASW perception on an average. This stimuli creates monotonic ASW perception with respect to change in number of loud speakers (physical source width). For a multi-component music signal, we observe that widest ASW is produced with a random inter-channel delay, compared to synchronous stimuli and segmental jittered stimuli. Thus, through this work, we develop an experimental methodology to study the large auditory source width using a linear loudspeaker array in an anechoic setup.

Good quality time-scale modification (TSM) of speech, and audio is a long standing challenge. The crux of the challenge is to maintain the perceptual subtilities of temporal variations in pitch and timbre even after time-scaling the signal. Widely used approaches, such as phase vocoder, and waveform overlap-add (OLA), are based on quasi-stationary assumption and the time-scaled signals have perceivable artifacts. In contrast to these approaches, we propose application of time-varying sinusoidal modeling for TSM, without any quasi-stationary assumption. The proposed model comprises of a mel-scale nonuniform bandwidth filter bank, and the instantaneous amplitude (IA), and instantaneous phase (IP) factorization of sub-band time-varying sinusoids. TSM of the signal is done by time-scaling IA, and IP in each sub-band. The lowpass nature of IA, and IP allows for time-scaling via interpolation. Formal listening tests on speech, and music (solo, and polyphonic) show reduction in TSM artifacts such as phasiness, and transient smearing. Further, the proposed approach gives improved quality in comparison to waveform synchronous OLA (WSOLA), phase vocoder with identity phase locking, and the recently proposed harmonic-percussive separation (HPS) based TSM methods. The obtained improvement in TSM quality highlights that speech analysis can benefit from appropriate choice of time-varying signal models.

Speaker identification implemented on a mobile robot is a challenging problem because of varying reverberant environments which the robot encounters while in motion. The performance of a typical speaker identification system degrades significantly in reverberant environments. The degradation in performance is mainly due to the conventional feature being not robust to change in reverberant condition. In this paper, we present a non-linear filter based mel frequency cepstral coefficient (MFCC) feature extraction, which is more robust to changes in reverberant conditions. This feature extraction method is a two stage operation and is applied on the spectrogram of the speech signal. The first stage suppresses the frequency spread due to reverberation within each frame and in the second stage, reverberation effect across the frames is suppressed. The performance is evaluated by the GMM-UBM based identifier built and tested with conventional MFCC feature vectors and with the non-linear filter based MFCC feature vectors. We show that, the identification accuracy of GMM-UBM based identifier with non-linear filter based MFCC feature vectors is better than that of conventional MFCC feature vectors.

Summary Background Patients with congenital ichthyosis, especially those with darker skin types, are at increased risk of developing vitamin D deficiency and rickets. The relationships between 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH) and bone health have not been studied previously, in ichthyosis. Objectives To determine the threshold levels of 25(OH)D and PTH for impaired bone health in children with congenital ichthyosis. Methods In this cross-sectional study, 119 children with ichthyosis and 168 controls were recruited. Serum 25(OH)D, PTH, calcium, phosphate and alkaline phosphatase (ALP) were measured. Radiological screening for rickets was carried out only in children with ichthyosis. Results Forty-seven children with ichthyosis had either clinical or radiological evidence of rickets. The correlation between serum 25(OH)D and PTH showed that a serum level of 25(OH)D 8 ng mL−1 was associated with a significant increase in PTH. The correlation between PTH and ALP showed that a serum PTH level of 75 pg mL−1 was associated with a significant increase in ALP levels. Of the different clinical phenotypes of ichthyosis, both autosomal recessive congenital ichthyosis (ARCI) and epidermolytic ichthyosis (EI) were found to have significantly increased PTH, ALP and radiological rickets scores compared with common ichthyosis. Conclusions Serum levels of 25(OH)D ≤ 8 ng mL−1 and PTH ≥ 75 pg mL−1 significantly increases the risk for development of rickets [odds ratio (OR) 2·8; 95% confidence interval (CI) 1·05–7·40; P = 0·04] in ichthyosis. Among the different types, patients with ARCI (OR 4·83; 95% CI 1·74–13·45; P

Background Host genetic factors that influence predisposition to anti-tuberculosis drug-induced hepatotoxicity (DIH) are not clear in the Indian population. Objective To investigate the possible association of DIH with polymorphism at the RsaI site of the 5-prime untranslated region of CYP2E1 and GSTM1 'null' mutations. Methods In this prospective study, 113 tuberculosis (TB) patients with DIH and 201 TB patients receiving anti-tuberculosis treatment without developing hepatotoxicity (non-DIH) constituted cases and controls, respectively. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to analyse genetic polymorphisms of CYP450 2E1 at the RsaI site and 'null' GSTM1 mutations. PCR-RFLP results were compared between 185 non-DIH and 105 DIH patients Results A high frequency of c1c1 genotypes of CYP2E1 was commonly encountered, and the difference between DIH and non-DIH patients was not significant (75.14% vs. 77.14%). The genotypic distribution of c2c2 was significantly higher in the DIH than in the non-DIH group (4.8% vs. 0.5%, OR 8.58, P = 0.03). However, adjustment for age, sex and serum albumin differences yielded an OR of 2.75, making it non-significant (P = 0.26). Homozygous 'null' mutation frequencies at the GSTM1 gene in DIH and non-DIH patients were observed that were not significantly different (40% and 37%, respectively, P = 0.61). Conclusion RsaI variants of the CYP2E1 gene and GSTM1 'null' mutation were not associated with risk of DIH in a north Indian population.

Background: Traumatic brain injury (TBI) and Subarachnoid Hemorrhage (SAH) are the leading cause of death and disability in both developed and developing countries. They have significant cognitive and behavioral consequences, affecting the quality of life of both patients and their families. Aim: To compare the memory functioning of TBI and SAH and study the effect of demographics on the same through a retrospective study. Materials and Methods: A sample of 210 patients clinically diagnosed as TBI ( N = 165; M = 145/ F = 20) and SAH ( N = 45; M = 35/ F = 10) were using post graduate institute of memory scale (PGI-MS) which assesses 10 memory domains. Results: Odds Ratio (OR) was calculated by categorizing the scores as average and impaired on PGI-MS, the percentage of impaired cases of SAH were significantly less as compared to TBI (8.9% vs. 22.4%; OR = 0.34) Moreover, only two domains were found to have significant results, i.e. delayed recall and recognition. When the scores were adjusted for age, education and gender, memory impairment was found to be statistically significant in domains of remote memory (OR = O.10) recent memory (OR = 0.32), delayed recall (OR = 0.26), immediate memory (OR = 0.30), new learning ability (OR = 0.38), and recognition (OR = 0.17). Conclusion: A primary prevention (awareness program about risk factors) and tertiary prevention (holistic rehabilitation) would play a crucial role in improving the quality of life of both patients as well as the population at risk.

Background Gemcitabine with platinum is regarded as the standard of care in patients with unresectable and/or metastatic disease with good performance status (PS). There is no standard of care for poor PS patients. A report from M.D.A.C.C. stated a median OS of only one month in GBC patients with poor PS. Erlotinib and capecitabine, both have shown efficacy in metastatic GBC. There has been no RCT to date in GBC patients with poor PS. With limited data showing the activity of erlotinib and capecitabine, we conducted this RCT to evaluate the efficacy and toxicity of these drugs in this patient cohort. Methods This is an ongoing open-label, phase II/III RCT (phase II part of the study is complete).The primary objective is to determine if erlotinib (150 mg/d PO )+ BSC or capecitabine (625 mg/m2 BD PO) + BSC has an OS benefit compared to BSC alone in patients with unresectable/metastatic GBC with ECOG PS III. A total of 51 patients with histopathologically confirmed GBC, age >/=18 years, with adequate organ functions (S. bilirubin 50 ml/min/1.73m2) were randomised. Patients were followed up q2wk in first month and q4wk thereafter. Toxicity was assessed using CTCAE v4.1. Radiological response evaluation (as per RECIST v1.1) was done at 8-10 weeks/earlier if clinically indicated, QoL assessment (using EORTC QLQ-C30 BIL21 ) was done at baseline and at 6-8 weeks. Intervention was continued until progression/unacceptable toxicity. Serial evaluation for OS in all three arms was done. Initially the study was started as a phase II RCT, an interim pre-planned analysis was done after completion of phase II. Results The median OS in capecitabine +BSC arm (n = 19) was 209 days, relotinib +BSC arm(n = 14) was 105 days and BSC alone arm was 71 days (p value 0.022). Only 2 patients had grade III diarrhea with erlotinib. There were no drug-related SAEs. Conclusions There is a statistically significant OS benefit of capecitabine+BSC or erlotinib+BSC over BSC alone in unresectable/metastatic GBC patients with ECOG PS III. Results will be updated upon completion of phase III. Clinical trial identification CTRI/2019/04/018860. Legal entity responsible for the study The authors. Funding All India Institute of Academic Sciences. Disclosure All authors have declared no conflicts of interest.

Background: Chronic dacryosystitis is a common condition affecting the eye and presenting to ENT surgeons and ophthalmologists, and treated with DCR (dacryocystorhinostomy). In few cases there can be recurrence of symptoms following DCR surgery which can be treated with bi-canalicular silicone intubation. The aim of this study is to assess the effectiveness of an early bi-canalicular silicone intubation in patients with failed DCR using endoscopic visualisation.Methods: This was a prospective observational study. Thirteen cases of DCR operated for chronic dacryocystitis at St John’s Medical College Hospital were reviewed between January 2014 and February 2017. Endoscopic DCR was done for five patients and external DCR for eight patients, number of males were 5 (38%) and females were 8 (62%). Age: 9–73 years (avg: 40.5 years). Results: Nine patients had complete resolution of symptoms following the primary DCR (4 following external DCR and 5 following endonasal endoscopic DCR). Four patients had failed DCR with persistence of watering three months following primary DCR surgery. Re-DCR with bi - canalicular silicon stent intubation was done in failed cases. Postoperative follow up of all the four patients showed complete resolution of symptoms.Conclusions: Failed DCR surgeries can be effectively intubated using bi–canlicular silicon tubes in the early postoperative period following DCR surgery. Silicone tube intubation is the most safe and cost effective method. Endoscopic visualization gives an added advantage of localizing the cause for a failed DCR.

Objective of the study was to evaluate the reliability of Muller’s maneuver (MM) with the severity of obstructive sleep apnea (OSA) at the retropalatal level. Case series of 58 adult patients diagnosed to have OSA. Sleep apnoea clinic in a tertiary referral center in south India. Fifty-eight adult OSA patients underwent outpatient based MM under local anaesthesia. Collapse of hypopharynx and the retroglossal regions were assessed during a maximal inspiratory effort against the closed mouth and sealed nose (reverse valsalva). Correlation co efficient was used to compare MM grade with apnea–hypopnea index (AHI) scores. Severity of OSA based on AHI scores were compared with the results of Muller’s maneuver at the retropalatal level. The correlation coefficient was 0.213, hence no correlation was found, p value was 0.019, which was not statistically significant. MM is an useful tool for evaluation of upper airway collapse. The advantages include simplicity, cost-effectiveness, relatively easy to perform, thorough evaluation of upper airway. The pitfalls of the procedure includes the subjectiveness of the procedure and the fact that it is performed on awake patients and therefore remains an indirect estimation of obstruction that occurs during sleep. In our study, we did not find correlation between the severity of OSA based on the AHI scores and the collapse at the retropalate level assessed by the Muller’s maneuver.

While anemia occurs in 80 % to 90 % of patients with celiac disease (CD), it may be the sole manifestation of CD. The prevalence of CD in Indian patients with nutritional anemia is not known. Adolescent and adult patients presenting with nutritional anemia were prospectively screened for CD using IgA anti-tissue transglutaminase antibody (anti-tTG Ab) followed, if positive, by upper gastrointestinal endoscopy and duodenal biopsy. Ninety-six patients [mean ± SD age 32.1 ± 13.1 years and median duration of anemia 11 months (range 1 to 144 months)] were screened. Of these patients, 80 had iron deficiency anemia, 11 had megaloblastic anemia, and 5 had dimorphic anemia. Seventy-three patients were on hematinics and 36.4 % had received blood transfusions. Nineteen had a history of chronic diarrhea and the mean ± SD duration of diarrhea in them was 9.7 ± 35.8 months. IgA anti-tTG Ab was positive in 13 patients, of whom 12 agreed to undergo duodenal biopsy. Ten patients had villous atrophy (Marsh grade 3a in three, 3b in one, and 3c in six) and two did not. Thus, 10 patients with nutritional anemia (iron deficiency 9, vitamin B12 deficiency 1) were diagnosed to have CD. On multivariate logistic regression, age, duration of symptoms, and presence of diarrhea were found to be the predictors of CD. All the patients with CD were put on gluten-free diet and with iron and vitamin supplementations and showed a significant improvement in hemoglobin concentration. CD screening should be included in the work up of otherwise unexplained nutritional anemia.

We address the problem of identifying the constituent sources in a single-sensor mixture signal consisting of contributions from multiple simultaneously active sources. We propose a generic framework for mixture signal analysis based on a latent variable approach. The basic idea of the approach is to detect known sources represented as stochastic models, in a single-channel mixture signal without performing signal separation. A given mixture signal is modeled as a convex combination of known source models and the weights of the models are estimated using the mixture signal. We show experimentally that these weights indicate the presence/absence of the respective sources. The performance of the proposed approach is illustrated through mixture speech data in a reverberant enclosure. For the task of identifying the constituent speakers using data from a single microphone, the proposed approach is able to identify the dominant source with up to 8 simultaneously active background sources in a room with RT60 = 250 ms, using models obtained from clean speech data for a Source to Interference Ratio (SIR) greater than 2 dB.

Background: Corneal blindness is a major form of visual impairment in developing countries and has been recognized as an important public health problem. There is limited population based data on the magnitude and causes of corneal blindness and morbidity in our country. Methods: An extensive search was performed to locate papers on the subject published 1991 onwards up to the present. Hand search of cross references was also done along with consultation with experts in order to enlarge the reference base. Results: Seven population based studies on blindness from various parts of the country, were found suitable for meta-analysis. The true prevalence of corneal blindness in people aged 50 years and above for each study was calculated from the reported prevalence. The true prevalence of corneal blindness in the adult Indian population is 4.5 per 1000 (95% CI: 2.7-6.4). The causes of corneal morbidity leading to corneal scarring and, eventually, blindness were also extensively studied.Conclusion: The present paper highlights that there is a significant burden of corneal blindness in the adult Indian population. As the majority of the ocular diseases leading to corneal blindness are avoidable, appropriate public education, health promotion measures, prompt treatment for corneal trauma and infections can be an effective strategy against corneal blindness.

In axial compressor distortion at inlet leads to adverse pressure gradient at inlet of fan which leads to performance degradation and adverse effects like vibration and noise. The major distortion can lead to surge or stall in compressor. Hence, this study involves creating distortions at inlet and studying its effects on stall and performance of compressor fan. To analyze effect of distortion on compressor, an axial ducted fan is used. Study is carried out for normal flow condition, hub distortion and radial distortion conditions. Static pressure is measured in two cases. In first case, for different mass flow rate, difference in the static pressure of fan is measured, for which performance characteristic curves are plotted. In second case, normal flow inlet is distorted at operating point using above said distortion methods and difference in static pressure of fan is measured for which efficiency of fan is calculated. 60% of flow at inlet is blocked in both the cases of distortion by mechanical means using screens. Velocity across the duct at fan inlet is calculated, for which mathematical models are found. From this, average velocity from hub to tip which is necessary to find efficiency is calculated. Study shows amount of distortion not only affects stall and surge margin but also type of distortion affects surge and stall of ducted fan. Radial distortion exhibits less amount of stall margin than hub distortion for same amount of inlet flow.

Flow at inlet of fan in an axial compressor must be one dimensional as developed flow so that angular momentum fed by the fan to incoming air is maximum. It is possible with good inlet design and optimum inlet length where we obtain stream line flow into fan with nominal boundary layer thickness. Distortion to the flow at fan inlet in an axial compressor is unavoidable problem. For example in aircraft gas turbine engine; flow at inlet of fan is distorted due to maneuvering of air craft, strong cross winds and atmospherics turbulence at inlet of compressor. Flow at inlet of fan affects boundary layer and hence the performance of compressor. Therefore, visualization of flow with boundary layers in an axial ducted fan setup is carried out for well-defined inlet conditions using pressure probes. To visualize the flow with boundary layer development at the fan inlet, static and stagnation pressure are measured throughout the inlet passage of duct using static and pitot probe and velocity is calculated across the given reference planes of duct using Bernoulli’s equation. Using these data, profile plots are drawn and mathematical models are developed and flow with boundary layer is analyzed. Under normal inlet flow condition flow in the duct inlet is axisymmetric, steady, turbulent and incompressible. Boundary layer develops consistently towards the fan inlet and it is nominal.

Most of airplane structures include the components such as Fuselage, Wings, Empennage, Landing gear and Power plant etc. Wings are the important part of aircraft and these are airfoils attached to each side of the fuselage and are the main lifting surfaces that support the airplane in flight. SSD-2 airfoil, a modified version of NACA23015 airfoil is used to study the aerodynamic characteristics such as lift, drag, moment and wall effects with different wind tunnel blockage ratios. Generally, any new airfoil characteristics are derived from the extensive wind tunnel tests, however experiments are costly. Hence, to get the idea of aerodynamic characteristics and wall effects over airfoil with different wind tunnel blockage ratios, CFD tools are used such as ICEM CFD and ANSYS FLUENT. This paper presents the results of simulation of flow past SSD-2 airfoil. The study is carried out on a 2D airfoil section for free stream condition. Further the computations are made on 3D rectangular wing of solid wind tunnel simulation by varying wind tunnel height to get the different wind tunnel blockage ratios, keeping the other parameters constant. In solid wind tunnel simulation the lift and moment are less compared to free stream simulation results due to blockage effects. Finally, it is observed that increase in the wind tunnel blockage ratio, lift and moment decreases, drag increases with less difference in pressure; whereas decrease in wind tunnel blockage ratio, the lift and moment increases, drag decreases with more difference in pressure.

Traditionally, visually challenged individuals employ the white cane to aid their mobility outdoors, which provides very limited utility. In order to improve the safety of visually challenged users and enhance their awareness of their surroundings while navigating in outdoor environments, a smart device is needed. In this paper, a smart walking cane for the visually challenged has been presented. The proposed device can detect obstacles as well as terrain changes in the user's path. A conventional walking cane forms the main frame of the device, upon which ultrasonic sensors are mounted at appropriate locations to detect obstacles, steps and pits in the path of the user. Additionally, a provision to indicate the presence of puddles and slippery surfaces in the user's path has also been included in the device. The presence of these obstacles is notified to the user by the means of voice recordings played via earphones or through haptic feedback, provided using vibration motors placed on the hand support of the stick. The smart walking cane further employs GPS and GSM modules which can be used to send a distress signal to the user's kin along with the user's location upon being activated by a simple press of a button. The device is lightweight and is powered by a rechargeable battery. The overall design of the device ensures accuracy, energy efficiency and easy portability.

We explore, experimentally, feature selection and optimization of stochastic model parameters for the problem of speaker spotting. Based on an initially identified segment of speech of a speaker, an iterative model refinement method is developed along with a latent variable mixture model so that segments of the same speaker are identified in a long speech record. It is found that a GMM with moderate number of mixtures is better suited for the task than a large number mixture model as used in speaker identification. Similarly, a PCA based low-dimensional projection of MFCC based feature vector provides better performance. We show that about 6 seconds of initially identified speaker data is sufficient to achieve > 90 % performance of speaker segment identification.

Background: Thrombocytopenia has been shown to predict mortality. We hypothesize that platelet indices may be more useful prognostic indicators. Our study subjects were children one month to 14 years old admitted to our hospital. Aim: To determine whether platelet count, plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width (PDW) and their ratios can predict mortality in hospitalised children. Methods: Children who died during hospital stay were the cases. Controls were age matched children admitted contemporaneously. The first blood sample after admission was used for analysis. Receiver operating characteristic (ROC) curve was used to identify the best threshold for measured variables and the ratios studied. Multiple regression analysis was done to identify independent predictors of mortality. Results: Forty cases and forty controls were studied. Platelet count, PCT and the ratios of MPV/Platelet count, MPV/PCT, PDW/Platelet count, PDW/PCT and MPV x PDW/Platelet count x PCT were significantly different among children who survived compared to those who died. On multiple regression analysis the ratio of MPV/PCT, PDW/Platelet count and MPV/ Platelet count were risk factors for mortality with an odds ratio of 4.31(95% CI, 1.69-10.99), 3.86 (95% CI, 1.53-9.75), 3.45 (95% CI, 1.38-8.64) respectively. In 67% of the patients who died MPV/PCT ratio was above 41.8 and PDW/Platelet count was above 3.86. In 65% of patients who died MPV/Platelet count was above 3.45. Conclusion: The MPV/PCT, PDW/Platelet count and MPV/Platelet count, in the first sample after admission in this case control study were predictors of mortality and could predict 65% to 67% of deaths accurately. Keywords: SICK Score, PRISM, severity of illness scores PIM, in-hospital mortality; platelet indices

Previous epidemiological studies suggest an association between psoriasis and metabolic syndrome and risk of subclinical atherosclerosis. However, there is a paucity of data in the Indian population on these associations.To evaluate the prevalence of metabolic syndrome and subclinical atherosclerosis in patients with chronic plaque psoriasis compared to healthy controls and to correlate the prevalence of metabolic syndrome with severity of psoriasis.A hospital-based cross-sectional study was performed on 140 patients with chronic plaque psoriasis and 140 controls. Psoriasis was categorized as mild, moderate and severe based on psoriasis area and severity index (10, 10-14 and ≥15, respectively) and as disease of short (1 year), intermediate (1-3 years) and long duration (3 years). In all patients and controls, body mass index was calculated, blood pressure and waist circumference were measured and fasting bloaod sugar and lipid profile were estimated. Metabolic syndrome was diagnosed by the presence of 3 or more of the modified National Cholesterol Education Program's Adult Treatment Panel III criteria. A subset of 30 psoriatic patients and 30 healthy controls were selected by the systematic sampling method for cardiac evaluation including electrocardiography, echocardiography and carotid intima-media thickness measurement.The prevalence of metabolic syndrome was significantly more in psoriatic patients than in controls (39.3% vs. 17.1%, odds ratio = 3.13). Psoriatic patients also had a significantly higher prevalence of hypertension, abdominal obesity and diabetes. There was a significant trend to increase in prevalence of metabolic syndrome, hypertension and type 2 diabetes with increased severity and longer duration of the psoriasis. Patients with psoriasis had significantly higher carotid intima-media thickness (mean 0.61 mm ± 0.01 mm vs. 0.37 mm ± 0.01 mm) than controls.This was a hospital-based cross-sectional study with a relatively small sample size. A prospective study with a larger sample would have validated the results further.There is a significantly higher prevalence of metabolic syndrome in psoriasis patients as compared to controls; the prevalence of metabolic syndrome and its components increases with severity and duration of psoriasis. There is a higher prevalence of subclinical atherosclerosis in patients with psoriasis thus increasing the risk of cardiovascular disease. We suggest that patients with moderate to severe psoriasis be screened routinely for metabolic syndrome and cardiovascular disease and encouraged to correct modifiable cardiovascular risk factors.

To determine the age of pubertal onset and menarche in school-going girls, and to assess the impact of obesity on pubertal timing. Cross-sectional Seven schools across Delhi, India. 2010 school girls, aged 6-17 years Anthropometric measurement and pubertal staging was performed for all subjects. Menarche was recorded by ‘status quo’ method. Body mass index was used to define overweight/obesity. Serum gonadotropins and serum estradiol were measured in every sixth participant. Age at thelarche and menarche—analyzed for entire cohort and stratified based on body mass index. Median (95% CI) ages of thelarche, pubarche and menarche were 10.8 (10.7-10.9) y, 11.0. y (10.8-11.2) y and 12.4 y (12.2-12.5) y. Overweight/obese girls showed six months earlier onset of thelarche and menarche than those with normal BMI (P

The Time Difference of Arrival (TDOA) of an acoustic source with respect to a given pair of microphones is typically estimated as the maximizer of a Measure of Synchrony (MoS) between the pair of microphone signals, within the interval [−D/v, D/v], where D is the inter-microphone distance and v is the speed of sound. In practical enclosures, phantom sources are created due to reverberation, which can cause false peaks in the MoS, leading to erroneous TDOA estimates. In several practical enclosures such as meeting rooms, conference halls, lecture halls, etc., the regions which can admit an acoustic source are restricted, because of furniture and other fixtures. Consequently, it is possible to acquire prior knowledge of the region which can accommodate an acoustic source. In this paper, we propose an approach to utilize this prior knowledge of source region for accurate TDOA estimation. We transform the prior knowledge of source region into an interval of possible TDOAs using a newly developed concept of family of hyperboloids. This interval, referred to as Region Constrained TDOA Interval (RCTI) is shown to be smaller than [−D/v, D/v]. TDOA is then estimated as the maximizer of a suitable MoS within the RCTI. We demonstrate that estimating TDOA within RCTI, with generalized cross correlation (GCC) class of functions as MoS, is more robust to reverberation than estimating TDOA within [−D/v, D/v].

Aim To evaluate the sensitivity and specificity of dual energy computed tomography (DECT) for diagnosing gout compared with a composite gold standard (CGS) comprising joint aspiration and/or American College of Rheumatology clinico-radiographic criteria. Methods Ninety patients of suspected gout underwent radiography and DECT of bilateral feet and knees. Radiographs and non-contrast CT (NCCT) were assessed for morphological characteristics, following which DECT was used to identify urate deposits. Results With CGS as a reference (n = 90), sensitivity of radiographs was 15% (95% confidence interval [CI]: 6–27%) while specificity was 100% (95% CI: 90–100%). Sensitivity of NCCT was 26% (95% CI: 15–40%) while specificity was 97% (95% CI: 85–99%). Sensitivity of DECT was 82% (95% CI: 68–90%) while specificity was 89% (95% CI: 73–96%). Fifty-five patients underwent joint aspiration. Sensitivity and specificity of radiographs and NCCT with aspiration as a reference (n = 55) were not much different from that of CGS. However, DECT showed a higher sensitivity of 100% (95% CI: 86–100%) and a lower specificity of 48% (95%CI: 28–68%) with aspiration alone. Conclusions Dual energy computed tomography had higher sensitivity compared to conventional imaging with CGS as a reference; however, its specificity dropped with aspiration as a reference. It may be a useful adjunct for the diagnosis of gout, especially in the acute and inter-critical stage.

Despite improved treatment options, recurrence rates remain high in ovarian cancer. Tumor microenvironment, particularly T cells, plays an important role in its natural history. The present study was conducted to study the kinetics of T cell subsets in homogenous population of advanced-stage ovarian cancer patients of serous histology with reference to treatment and outcome. We assessed the frequencies of CD8+ T cells, CD4+ T cells, regulatory T cells (Tregs, CD4+ CD25intermediate to high FOXP3+ CD127low) and natural killer cells in peripheral blood at baseline (n = 41) and post-treatment (n = 27) in the patients and compared it with blood of healthy controls (n = 15). The ascitic fluid of 12 of these patients was compared with ascitic fluid of patients with cirrhotic liver disease (n = 5). Higher numbers of Tregs, CD8+ T cells and higher Treg/CD4 ratio and reduced numbers of CD4+ T cells and reduced CD4/CD8 ratio were observed in patients as compared to controls. An increase in total number of T cells was observed with treatment, while no change in frequency of any lymphocyte subset was evident. These results support previous studies exhibiting an increase in Tregs in ovarian cancer patients. Unchanged levels of T cell subsets subsequent to treatment suggest that they may be resistant to reset to healthy control homeostatic levels with standard chemotherapeutic treatments. Lower CD4 levels, higher CD8 levels, altered CD4/CD8 ratio and T cell subsets call for evaluation of role of immunomodulating agents or Treg-targeted immunotherapy in the treatment of advanced-stage serous carcinoma ovary.

We propose a short-time polynomial regression (STPR) for time-varying signal analysis. The advantage of using polynomials is that the notion of a spectrum is not needed and the signals can be analyzed in the time domain over short durations. In the presence of noise, such modeling becomes important, because the polynomial approximation performs smoothing leading to noise suppression. The problem of optimal smoothing depends on the duration over which a fixed-order polynomial regression is performed. Considering the STPR of a noisy signal, we derive the optimal smoothing window by minimizing the mean-square error (MSE). For a fixed polynomial order, the smoothing window duration depends on the rate of signal variation, which, in turn, depends on its derivatives. Since the derivatives are not available a priori, exact optimization is not feasible. However, approximate optimization can be achieved using only the variance expressions and the intersection-of-confidence-intervals (ICI) technique. The ICI technique is based on a consistency measure across confidence intervals corresponding to different window lengths. An approximate asymptotic analysis to determine the optimal confidence interval width shows that the asymptotic expressions are the same irrespective of whether one starts with a uniform sampling grid or a nonuniform one. Simulation results on sinusoids, chirps, and electrocardiogram (ECG) signals, and comparisons with standard wavelet denoising techniques, show that the proposed method is robust particularly in the low signal-to-noise ratio regime.

Methods for producing metal foams are many, but obtaining repeatability in the properties is very difficult. The main challenge posed by the metal foam is that obtaining homogeneous porosity. Although lot of problems involved in the development of metal foams, research people are attracted to the metal foams because of its attractive properties like acoustic damping, bomb mitigation, light weight etc. By considering the development of Aluminum foams as important aspect, some methods have been adopted and attempts have been made to produce metal foams at lower cost. The methods developed for the Aluminum foams were Aluminum foam production using NaCl crystal as a place holder in the Al melt, Aluminum foam production using NaCl crystal as a place holder in sand salt mold, Aluminum foam production using NaCl crystal as a place holder by simultaneous pouring concept.The problems associated in each process and its effect on the density and porosity of the foam were discussed.

Acoustic modeling using mixtures of multivariate Gaussians is the prevalent approach for many speech processing problems. Computing likelihoods against a large set of Gaussians is required as a part of many speech processing systems and it is the computationally dominant phase for Large Vocabulary Continuous Speech Recognition (LVCSR) systems. We express the likelihood computation as a multiplication of matrices representing augmented feature vectors and Gaussian parameters. The computational gain of this approach over traditional methods is by exploiting the structure of these matrices and efficient implementation of their multiplication. In particular, we explore direct low-rank approximation of the Gaussian parameter matrix and indirect derivation of low-rank factors of the Gaussian parameter matrix by optimum approximation of the likelihood matrix. We show that both the methods lead to similar speedups but the latter leads to far lesser impact on the recognition accuracy. Experiments on 1,138 work vocabulary RM1 task and 6,224 word vocabulary TIMIT task using Sphinx 3.7 system show that, for a typical case the matrix multiplication based approach leads to overall speedup of 46 % on RM1 task and 115 % for TIMIT task. Our low-rank approximation methods provide a way for trading off recognition accuracy for a further increase in computational performance extending overall speedups up to 61 % for RM1 and 119 % for TIMIT for an increase of word error rate (WER) from 3.2 to 3.5 % for RM1 and for no increase in WER for TIMIT. We also express pairwise Euclidean distance computation phase in Dynamic Time Warping (DTW) in terms of matrix multiplication leading to saving of approximately ${1} \over {3}$ of computational operations. In our experiments using efficient implementation of matrix multiplication, this leads to a speedup of 5.6 in computing the pairwise Euclidean distances and overall speedup up to 3.25 for DTW.

There is limited information available about the prevalence and pattern of human immunodeficiency virus (HIV) drug resistance mutations (DRMs) among antiretroviral therapy (ART) experienced patients from northern India. Results of genotypic drug resistance testing were obtained from plasma samples of 128 patients, who had presented with clinical or immunological failure to treatment after at least six months of ART. Major DRMs associated with any of the three classes of antiretroviral (ARV) drugs, nucleoside reverse transcriptase inhibitors (NRTI), non-nucleoside reverse transcriptase inhibitors (NNRTI) and protease inhibitors (PI), were seen in 120 out of 128 patients (93.8% prevalence). NRTI and NNRTI DRMs were each seen in 115/128 (89.8%) patients, with M184V, M41L, D67N and T215Y being the most frequent among NRTI associated mutations, and K103N, G190A, Y181C and A98G among NNRTI associated ones. PI DRMs were observed in 14/128 (10.9%) patients, with L10I, V82A and L89V being the commonest. These results present a high prevalence of DRMs among ART experienced patients from northern India with clinical or immunological failure of therapy. It emphasizes the need for regular testing of plasma samples of such patients for DRMs in order to detect and replace a failing regimen early, and also the use of HIV drug resistance genotyping of ART naive individuals prior to initiating first line ART for possible transmitted resistance. It is very important to enhance the access of patients to ARV drugs so that their compliance could be improved and hence development of DRMs be minimized.

Pulmonary artery hypertension (PAH) remains the leading cause of morbidity and mortality in systemic sclerosis, while Raynaud's phenomenon and digital ulcers significantly add to the morbidity in systemic sclerosis (SSc). This study was undertaken to evaluate the role of sildenafil in PAH, Raynaud's phenomenon, and digital ulcers in systemic sclerosis patients. A prospective, open-label, uncontrolled pilot study was done at a tertiary care centre in India to study the safety and efficacy of oral sildenafil in PAH, Raynaud's phenomenon, digital infarcts, and ulcers in SSc. Seventeen patients fulfilling ACR classification criteria for scleroderma and having PAH were recruited. Six-minute walk test, WHO class of dyspnoea, severity of Raynaud's phenomenon, and 2D ECHO were performed in all the study subjects at baseline and at 3 months post-treatment. All patients were treated with oral sildenafil 25 mg three times a day for a period of 3 months. The pre- and post-treatment values of mean pulmonary artery pressure (PAP), 6-min walk test, WHO class of dyspnoea, and severity of Raynaud's phenomenon were compared to look for any significant change. Sixteen patients who completed 3-month follow-up had shown statistically significant improvement in 6-min walk test, WHO class of dyspnoea, severity of Raynaud's phenomenon, and mPAP. Also, there was no occurrence of new digital infarcts or ulcers, and existing ulcers showed signs of healing. Sildenafil is highly efficacious cheaper and safe alternative to other available therapies for SSc-associated PAH, Raynaud's phenomenon, and digital infarcts/ulcers.

Background/Aims To study the prevalence of somatic and psychiatric co-morbidities in the patients of irritable bowel syndrome (IBS) and to assess the quality of life (QOL) of these patients. Methods One hundred and eighty-four IBS patients and 198 controls were included. Diagnosis of IBS, its sub-classification and assessment of other functional gastrointestinal disorders (FGIDs) was made on basis of Rome III criteria. Severity of IBS was assessed using IBS severity scoring system. Psychiatric evaluation was done using Patient Heath Questionnaire. QOL was evaluated using WHO QOL-BREF. Results One hundred and forty-seven (79.9%) and 158 (85.9%) patients with IBS had at least one other FGID or at least one somatic co-morbidity, respectively. Higher number of patients had at least one psychiatric co-morbidity compared to controls (79.9% vs 34.3%; P < 0.001). Major depressive syndrome (47.3% vs 5.1%; P < 0.001), somatoform disorder (50% vs 14.6%; P < 0.001) and panic syndrome (44% vs 11.6%; P < 0.001) were more common in IBS than controls. Only 14 (7.6%) patients were receiving drug treatment for their psychiatric illness. Severe IBS symptoms were present in significantly higher number of patients with constipation predominant IBS than diarrhea predominant IBS. Those with severe disease had higher prevalence of psychiatric (95.1%) and somatic (96.7%) co-morbidities compared with mild disease. QOL of IBS patients was significantly lower in all four domains compared to controls. Presence of at least one other FGID was significantly associated with presence of one or more psychiatric co-morbidity (P < 0.001). Conclusions Majority of IBS patients presenting to a tertiary care center had associated psychiatric, somatic co-morbidities and reduced QOL. Very few of them received specific psychiatric treatment.

Background and Aim: Pegylated-interferon-alfa (PEG-IFN-a) with ribavirin is an established treatment in chronic hepatitis due to hepatitis C virus (HCV) (CH-C). Such treatment is expensive and in resource-poor countries such as India, alternative less expensive therapy is needed. Methods: Multicenter randomized controlled trial comparing two treatment regimens (interferon-alfa-2b [IFN-a-2b] 3 million unit/day [MU/day] and ribavirin 1000 mg/day [I + R] vs IFN-a-2b 3 MU/day and glycyrrhizin 250 mg [I + G]) in CH-C. Viral, host characteristics and therapeutic responses were assessed (ICMR—6 months trial for chronic hepatitis—CTRI/2008/091/000105). Results: One hundred and thirty-one patients meeting the inclusion criteria were randomized to I + G (n = 64) or I + R (n = 67) during the period February 2002 to May 2005. About 85% (I + G = 53, I + R = 58) completed 6 months of treatment and 89% of them (I + G = 46, I + R = 53) completed 6 months of follow-up after completion of treatment. Hepatitis C virus genotype 3 was the major type detected (71% patients). The mean log10 viral load (copies/mL), histological activity index, and fibrosis stage for all patients were 5.1 ± 0.98, 5 ± 2, and 2 ± 1.5, respectively. Sustained viral response (SVR) was significantly higher in I + R group than in I + G group (65.7% vs 46.9%, OR = 2.2, P = 0.03). Treatment with I + G was associated with significantly lower frequencies of leukopenia (2% vs 17%, P < 0.01) and anemia (8% vs 40%, P < 0.001) as compared to treatment with I + R. Conclusion: Genotype 3 HCV infection with low viral load is prevalent in India. Daily IFN with ribavirin showed significantly better responses. Leukopenia and anemia were significantly more in ribavirin group. Responses observed with IFN + ribavirin were similar to the reported response rates with PEG-IFN suggesting that this modality may be considered as a cheaper alternative of treatment for chronic hepatitis C. ( J CLIN EXP HEPATOL 2012;2:10–18)

Objective The objective was to estimate the prevalence of psychiatric morbidity amongst patients attending Mobile Health Clinic (MHC) in an urban community in South Delhi. Methods Adult subjects were recruited by systematic random sampling at outpatient MHC. Primary Care Evaluation of Mental Disorder Patient Health Questionnaire (PHQ) was used for screening, and Mini International Neuropsychiatric Interview (M.I.N.I.) was used for the confirmation of diagnosis of psychiatric disorder of all PHQ-positive and 20% of PHQ-negative patients. Association of selected sociodemographic factors with psychiatric morbidity was also assessed. Results In total, 350 subjects were recruited, out of which 92 (26.3%) [95% confidence interval (CI) 21.7–31.0] were found to be PHQ positive. M.I.N.I. was administered to 141 subjects (92 PHQ positives and 52 PHQ negatives). Total estimated magnitude of psychiatric morbidity by M.I.N.I. was 25.4% (95% CI 20.9–29.9). Depression (15.7%) was observed to be the most common psychiatric disorder followed by generalized anxiety disorder (11.1%) and phobic disorders (10.1%). Suicidal ideation was reported by 37 (10.6%) patients. Literate status [odds ratio (OR)=0.43] and duration of migration >20 years to study area (OR=1.27) were found to be significantly associated with psychiatric morbidity. Conclusion In resource-poor country like India, high psychiatric morbidity at MHC justifies the use of MHC for providing outreach mental health services in difficult areas.

Summary Background Ichthyosiform erythroderma due to keratinizing disorders may suppress cutaneous vitamin D synthesis, leading to vitamin D deficiency and rickets. Objectives To determine the prevalence of vitamin D deficiency and rickets in children and adolescents with congenital ichthyosis and other keratinizing disorders with erythroderma and scaling. Patients and methods In this cross-sectional study, 45 children and adolescents with ichthyosiform erythroderma due to keratinizing disorders, and 66 controls (group 1: age and sex matched, with skin diseases other than keratinizing disorders; group 2: age and sex matched, healthy volunteers) were included. Evidence of rickets was determined clinically (physical examination and radiographs) and biochemically {serum calcium, phosphorus, alkaline phosphatase, 25-hydroxy vitamin D [25(OH)D] and parathyroid hormone (PTH)}. Results All patients in the disease group had clinical, radiological or biochemical evidence of rickets [25(OH)D 65 pg mL−1) was also significantly higher in the disease group than in controls (P

To demonstrate the role of oral acyclovir in monthly regimes after microdebrider assisted excision in 3 patients with adult recurrent respiratory papillomatosis (ARRP). Three patients with ARRP who presented to a tertiary referral hospital in stridor were initially treated with a tracheostomy in order to secure airway. On further evaluation by videolaryngoscopy extensive bilateral laryngeal papillomatosis was noted with history of similar conditions in the past for which they were repeatedly operated. They were admitted and underwent Microlaryngeal surgery and laryngeal microdebrider assisted surgery under general anesthesia. Post operatively a course of oral acyclovir at 800 mg/5 times/day for 5 days was administered. On repeat assessment with videolaryngoscopy at monthly intervals a complete remission of the disease was noted with no residual disease at the end of 1 year in 2 cases. One case had a recurrence. Renal parameters were monitored periodically. It may be concluded that the action of anti viral drugs at regular intervals in addition to a short course of oral steroids lead to rapid recovery and prevented latent virus activation within the laryngo tracheal system hence maintaining long term improvement. This can avoid multiple laryngeal surgeries, repeated respiratory emergencies and risk for malignant transformation in the future thereby reducing morbidity and effect on quality of life.

Background and objectives:The incidence of acquired laryngeal stenosis is increasing. This retrospective study aimed to assess the long term results of circumferential resection with end-to-end tracheal anastomosis for isolated post-intubation stenosis of the cervical trachea, and to review the relevant literature.Methods:Twelve male and two female patients (aged 16–30 years, mean age 24 years) treated between February 2003 and December 2008 were included. Hospital and office records were reviewed and relevant surgical details recorded.Results:Indications for tracheal resection anastomosis were post-intubation stenosis (78.57 per cent) and trauma (21.42 per cent). One to five tracheal rings were resected (i.e. 1–2.5 cm of cervical trachea). Tracheal anastomosis was considered successful if the patient remained asymptomatic for 24 months of close follow up (involving regular flexible bronchoscopy and neck X-ray). The anastomotic success rate was 92.85 per cent.Conclusion:Tracheal resection and end-to-end anastomosis is relatively safe and reliable for definitive treatment of benign tracheal stenosis in appropriate patients. Local application of mitomycin C prevents granulation and aids long term airway patency.

Summary Background Current noncultured cell-based transplantation therapies for vitiligo largely involve shave skin biopsy for preparation of noncultured melanocyte suspension. As the overall proportion of melanocytes is low in the epidermis, these techniques require basal cell layer enrichment, which adds additional steps. We tried follicular unit extraction (FUE) to harvest hair follicles as a source of melanocytes. Objectives To evaluate the efficacy of a novel surgical method for vitiligo: noncultured extracted hair follicular outer root sheath (ORS) cell suspension transplantation. Methods Fourteen patients with vitiligo, stable for at least 3 months, were included in this prospective study. Fifteen to 25 hair follicles were extracted from occipital scalp using the FUE method. Hair follicles were incubated with trypsin–ethylenediamine tetraacetic acid solution at 37 °C for 90 min to separate ORS cells. The cell suspension was filtered through a 70-μm cell strainer, then centrifuged for 5 min at 1000 r.p.m. to obtain a cell pellet. The pellet was resuspended and applied to the dermabraded recipient area and dressed. Results The mean ± SD repigmentation was 65·7 ± 36·7%. Overall, nine of 14 patients achieved > 75% repigmentation. Mean percentage repigmentation was significantly higher in patients with ≥ 1 year stability than those with

Studies on Pneumocystis jirovecii dihydropteroate synthase (DHPS) genotypes among non-HIV immunocompromised patients from developing countries are rare. In the present prospective investigation, 24 (11.8%) cases were found to be positive for Pneumocystis jirovecii out of 203 non-HIV patients with a clinical suspicion of Pneumocystis pneumonia (PCP). Dihydropteroate synthase (DHPS) genotype 1 (Thr55+Pro57) was noted in 95.8% P. jirovecii isolates in the present study in contrast to only 4.1% of patients with DHPS genotype 4 (Thr55Ala + Pro57Ser).

Early experience has a profound influence on brain development, and the modulation of prenatal perceptual learning by external environmental stimuli has been shown in birds, rodents and mammals. In the present study, the effect of prenatal complex rhythmic music sound stimulation on postnatal spatial learning, memory and isolation stress was observed. Auditory stimulation with either music or species-specific sounds or no stimulation (control) was provided to separate sets of fertilized eggs from day 10 of incubation. Following hatching, the chicks at age 24, 72 and 120 h were tested on a T-maze for spatial learning and the memory of the learnt task was assessed 24 h after training. In the posthatch chicks at all ages, the plasma corticosterone levels were estimated following 10 min of isolation. The chicks of all ages in the three groups took less (p < 0.001) time to navigate the maze over the three trials thereby showing an improvement with training. In both sound-stimulated groups, the total time taken to reach the target decreased significantly (p < 0.01) in comparison to the unstimulated control group, indicating the facilitation of spatial learning. However, this decline was more at 24 h than at later posthatch ages. When tested for memory after 24 h of training, only the music-stimulated chicks at posthatch age 24 h took a significantly longer (p < 0.001) time to traverse the maze, suggesting a temporary impairment in their retention of the learnt task. In both sound-stimulated groups at 24 h, the plasma corticosterone levels were significantly decreased (p < 0.001) and increased thereafter at 72 h (p < 0.001) and 120 h which may contribute to the differential response in spatial learning. Thus, prenatal auditory stimulation with either species-specific or complex rhythmic music sounds facilitates spatial learning, though the music stimulation transiently impairs postnatal memory.