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Dynamic spectrum allocation (DSA) approach offers an effective means to wireless service providers (WSPs) for efficient utilization of their spectrum resources in order to manage their heterogeneous network (HetNet). The architecture for implementation of DSA has been proposed in IEEE 1900.4 standard. Under the IEEE 1900.4 framework, we envisage a scenario in which, the spectrum available with the WSP is inadequate to serve the aggregate demands of channels or the spectrum, from its radio access networks (RANs). Hence, a plausible solution has been sought in this work that employs and implements the notion of the Bankruptcy Game to formulate a policy decision which would certainly be agreeable to all the RANs. Maximization of proportional fairness (PF) is selected as the potential objective of the WSP. To arrive at an efficient solution that suits the objective of the WSP, we have proposed a novel heuristic namely, H_MPF and have compared the performance of the H_MPF with those of the Shapley value and simulated annealing based channel allocation (SACA) techniques considering solution quality and computational time as the performance indices.

The design and construction rules for nuclear components at elevated temperatures are currently in the ASME BPV Code, Section III, Division 1, Subsection NH, and will soon be incorporated in the new Section III, Division 5. The current allowable stresses are limited to 300,000 hours, which is equivalent to a 40-year design life. As a part of the Next Generation Nuclear Plant (NGNP) initiative, the allowable stress values are being revised to include higher temperatures and longer lifetimes. This is expected to support the design and construction of high temperature reactors for sixty-year (500,000-hour) design lifetimes. The technical bases for the revised temperature and time dependent stress allowable values for Type 304 and Type 316 stainless steels are presented in this paper. Since the allowable stresses at elevated temperatures are controlled by creep, the revised allowable stresses are based on Larson-Miller parametric analyses of creep data from Oak Ridge and NIMS, some of which was not available when the current allowable stresses were computed. The time-dependent stress intensity values (St) are based on ASME rules covering time to rupture, time to reach 1% strain and time to reach the onset of tertiary creep. The effect of the tertiary creep criterion on St at long times and high temperatures is significant. The tertiary creep criterion applied to the current Oak Ridge and NIMS data results in lower and more conservative high temperature and long time allowable stress values than those currently in Section III, NH. The potential reasons for the limiting tertiary creep effects are discussed, with the conclusion that the ASME graphical method specified to determine the onset of tertiary creep from the creep data is not appropriate for Type 316 stainless steel.Copyright © 2015 by ASME

This paper documents the basis for the current time dependent allowable stress criterion based on onset of third stage creep. The criterion is one of three that are used to develop allowable stresses for elevated temperature, Class 1, nuclear components*. The recommendation to consider third stage creep is part of a 1970 position paper prepared by one of the authors for the Task Force on Material Behavior of the Subgroup on Elevated Temperature Design. The position paper recommended that allowable stress/strain limits be set to preclude operation in third stage creep. This was based on the difficulty (at the time) of predicting the effects of multiaxial stresses on creep behavior and the possibility of through-wall cracks appearing before rupture. The principal references supporting this recommendation reported experimental results in which pressurized tubes failed almost exclusively before the onset of third stage creep. Also included are the reported results from a 1993 long term creep and rupture test of a nozzle-to-sphere model in which failure was also by small pinhole leaks prior to observed onset of third stage creep. In addition to excerpts from the above references, commentary from a current perspective is also provided.Copyright © 2015 by ASME

Factor VIII (FVIII) mutations cause haemophilia A (HA), an X-linked recessive coagulation disorder. Over 1000 missense mutations in FVIII are known and they lead to variable clinical phenotypes (severe, moderate and mild). The exact molecular basis of this phenotypic heterogeneity by FVIII missense mutations is elusive to date. In this study, we aimed to identify the severity determinants that cause phenotypic heterogeneity of HA. We compiled and curated a data set of 766 missense mutations from the repertoire of missense mutations in FVIII. We analysed these mutations by computational programs (e.g. Swiss-PdbViewer) and different mutation analysis servers (e.g. SIFT, PROVEAN, CUPSAT, PolyPhen2, MutPred); and various sequence- and structure-based parameters were assessed for any significant distribution bias among different HA phenotypes. Our analyses suggest that 'mutations in evolutionary conserved residues', 'mutations in buried residues', mutation-induced 'steric clash' and 'surface electrostatic potential alteration' act as risk factors towards severe HA. We have developed a grading system for FVIII mutations combining the severity determinants, and the grading pattern correlates with HA phenotype. This study will help to correctly associate the HA phenotype with a mutation and aid early characterization of novel variants.

Oculocutaneous albinism (OCA) is a heterogeneous group of autosomal recessive disorders characterized by an abnormally low amount of melanin in the eyes, skin and hair, and associated with common developmental abnormalities of the eye. Defects in the tyrosinase gene (TYR) cause a common type of OCA, known as oculocutaneous albinism type 1 (OCA1). The molecular basis of OCA has been studied extensively in different population groups, but very little information is available on Indian patients. Our investigation covering thirteen ethnic groups of India, some representing >20 million people, revealed that among 25 OCA families 12 were affected with OCA1, and that these cases were primarily due to founder mutations in TYR. We detected nine mutations and eight SNPs in TYR, of which six mutations (five point mutations & one gross deletion) were novel. In contrast to most reports describing compound heterozygotes, the presence of homozygotes in 10 out of the 12 pedigrees underscores the lack of intermixing between these ethnic groups in India. Haplotype analysis suggested a few founder chromosomes causing the disease in the majority of the patients. Direct detection of the mutations prevalent in specific ethnic groups could be used for carrier detection and genetic counselling.

In West Bengal, India, more than 300,000 arsenic-exposed people are showing symptoms of arsenic toxicity, which include cancers of skin and different internal organs. Since only 15-20% of the exposed population manifest arsenic-induced skin lesions, it is thought that genetic variation might play an important role in arsenic toxicity and carcinogenicity. A total of 422 unrelated arsenic-exposed subjects (244 skin-symptomatic and 178 asymptomatic) were recruited for this study. Cytogenetic damage, as measured by chromosomal aberrations in lymphocytes and micronuclei formation in oral mucosa cells, urothelial cells and binucleated lymphocytes, was studied in unexposed, skin-symptomatic and asymptomatic individuals with similar socioeconomic status. Identification of null mutations in GSTT1 and GSTM1 genes were carried out by PCR amplification. GSTP1 SNPs, implicated in susceptibility to various cancers, were assessed by PCR-RFLP method. Symptomatic individuals had higher level of cytogenetic damage compared to asymptomatic individuals and asymptomatic individuals had significantly higher genotoxicity than unexposed individuals. No difference in allelic variants in GSTT1 and GSTP1 was observed between these 2 groups. Incidence of GSTM1 null gene frequencies was significantly higher in the asymptomatic group. Individuals with GSTM1-positive (at least one allele) had significantly higher risk of arsenic-induced skin lesions (odds ratio, 1.73; 95% confidence interval, 1.24-2.22). These results show a protective role of GSTM1 null in arsenic toxicity. This study also indicates that asymptomatic individuals are sub clinically affected and are also significantly susceptible to arsenic-induced genotoxicity.

This paper presents design, fabrication, simulation and experimental verification of the Phase Modulated Resonant Transition Converter (PMRTC). This PMRTC forms a part of a scaled down welding converter prototype developed in the laboratory. The PMRTC performance has been simulated offline by using SEQUEL. These results have been verified with the experimental results obtained from the fabricated set-up. Excellent correlation between simulated and experimental results uphold the accuracy of the work.

This paper presents detailed steps and procedure for the design of a permanent magnet brush-less DC machine(PM-BLDC). Here the design(both the armature circuit and the PM field) is done for a 4-pole 0.75 hp, 1500 rpm surface mounted BLDC(SPM-BLDC). First the design and the performance analysis of the machine has been done by hand calculation. The results are then fine tuned and verified using a standard finite element analysis(FEM) software. Parameters of the machine have also been calculated. The designed BLDC motor also have been fabricated.

Modern induction heating (IH) power converters operate marginally above resonant frequency to supply power to the targeted work-piece at near unity power factor (upf). The resonant frequency continuously increases as the work-piece gets heated up. A possible method of dynamically detecting the resonant frequency may be to calculate the phase-shift between current and voltage continuously during the process. The phase-shift between voltage and current is ideally zero at resonance. So resonant frequency may be identified by varying the frequency until the phase-shift is zero. For this some controllers use a phase-locked loop (PLL) strategy. In this paper, the dynamic tracking of resonant frequency, using a field-programmable gate array (FPGA) based digital-PLL, is presented. The scheme is first simulated off-line. Finally, the logic is implemented on controller hardware and practically tested in a laboratory made experimental set-up of 2kW at around 10kHz.

This paper describes the design, modelling, fabrication and control of an attraction type electromagnetic levitation prototype with single-axis control. The system is simulated using standard FEM packages and used in control system related investigations. The mathematical model of the system has also been derived. Experiments have also been carried out. Practically evaluated system parameters show excellent agreement with the values estimated using FEM calculations. Two stabilising controllers, an inner current controller (P controller) and an outer position controller (lead compensator) have been designed for this system and also implemented on the practical setup.

This paper presents steps and procedure for the design of a 3-phase, 6 pole, 245V, 2kVA, surface mounted permanent magnet synchronous generator(PMSG). First the design and the performance analysis of the machine has been done by hand calculations. The results are then fine tuned and verified using a standard Finite Element Method package. Parameters of the machine have also been calculated. Static rotor shaft deflection and critical speed of the rotor have been calculated. The PMSG has been fabricated locally and is presently being tested.

In this paper, a control strategy for switched reluctance motor(SRM) based variable speed drives is proposed. The phase inductance profile for an SRM being nonlinear, a small signal model based method is applied in a restricted way to design and then implement the controllers based on a linearised model. Two control loops — a Pi-controller based speed loop and and a hysteresis controller current loop — have been used. Excellent correlation between simulation and experimental results establish the accuracy of the proposed control strategy and the precision of its implementation.

This paper presents methods of design, theoretical determination and practical evaluation of machine parameters of an 8-pole, 5kW permanent magnet synchronous motor(PMSM). This motor had been designed in the laboratory and fabricated by a local manufacturer after procuring imported magnets. The practically evaluated parameters are found to be in excellent agreement with theoretically estimated values. This fact highlights the accuracy of the design, preciseness of fabrication and the reliability of the testing exercise.

This paper presents the design, fabrication, simulation and testing of repulsion type electromagnetic levitation system consisting of an inner levitating coil, an outer stabilizing coil and a 144 gm circular aluminium disc fed from a CSI (current source inverter). First the electromagnetic system is simulated using available FEM package and its performance is predicted. Thereafter, off-line simulation of the power converter is done using an open source circuit simulation package SEQUEL. Finally, experiments have been carried out and successful stable levitation has been achieved at a nominal frequency of 300Hz. The results of off line circuit simulation show excellent agreement with the experimental results and waveforms.

The genus Asparagus comprises three subgenera of cladode bearing plants: Protasparagus, Asparagus, and Myrsiphyllum. The interspecific delimitation of the subgenus Protasparagus is ill-defined till date. In the present study, interspecific phylogenetic relationships among nine taxa of Protasparagus based on ribosomal DNA internal transcribed spacer region (ITS1-5.8S-ITS2) sequence and the chloroplast DNA trnL intron sequence conservation with their cladode morphology, anatomy, and stomatal characteristics have been analyzed for the first time. The monophyletic subgenus Protasparagus could be resolved into four strongly supported distinct subclades (I, II, III and IV) suggesting that the rDNA and cpDNA molecular phylogenies are explicitly congruent with the cladode characteristics of the subgenus Protasparagus. The present study also confirms the existing subgeneric classification of the genus Asparagus with the monophyletic origin of the dioecious subgenus Asparagus. The present work brings out phylogenetic and taxonomic relationships within the studied taxa of the subgenus Protasparagus therefore providing important background information for further studies on biogeography of a wide range of species.

Connexin50 (Cx50) mutations are reported to cause congenital cataract probably through the disruption of intercellular transport in the lens. Cx50 mutants that undergo mistrafficking have generally been associated with failure to form functional gap junction channels; however, sometimes even properly trafficked mutants were found to undergo similar consequences. We hereby wanted to elucidate any structural bases of the varied functional consequences of Cx50 missense mutations through in silico approach. Computational studies have been done based on a Cx50 homology model to assess conservation, solvent accessibility, and 3-dimensional localization of mutated residues as well as mutation-induced changes in surface electrostatic potential, H-bonding, and steric clash. This was supplemented with meta-analysis of published literature on the functional properties of connexin missense mutations. Analyses revealed that the mutation-induced critical alterations of surface electrostatic potential in Cx50 mutants could determine their fate in intracellular trafficking. A similar pattern was observed in case of mutations involving corresponding conserved residues in other connexins also. Based on these results the trafficking fates of 10 uncharacterized Cx50 mutations have been predicted. Further experimental analyses are needed to validate the observed correlation.

The specificity of single nucleotide polymorphisms (SNPs) is likely to be compromised with most of the current PCRbased methods used to genotype a target locus in the presence of a highly homologous duplicated region. Such a lack of locus specificity could inflate the heterozygosity of the SNPs. We reasoned that public database for SNPs might be influenced by false allele calls, specifically in genes with copy number variation (CNV). Therefore, we compared the fraction of SNPs with high heterozygosity values (≥ 0.4) in NCBI dbSNP for genes with and without CNVs. Our observation highlights the challenges of selecting SNPs in genes with CNV for usage in complex biological studies.

With the advancement of medical science, average life expectancy of individuals is ever increasing. Percentage of elderly population has increased from 6.2% in 1990 to 8.2% in 2015 worldwide (http://www.unescap.org/resources/1-population). However, with increasing life expectancy, the prevalence of age related diseases will also increase, which will affect the quality of life in elderly population worldwide. Eye is our window to the outer world and deterioration of this vital organ with age will definitely affect the lifestyle of the elderly people. According to WHO, approximately 65% of the population aged over 50 years has some forms of visual impairment (http://www.who.int/mediacentre/factsheets/fs282/en/). Therefore, understating and managing the age related changes in eye calls for significant effort and attention from the scientific world. This special issue focuses on the age related changes and diseases of eye as well as their management in elderly population. Eight meticulously chosen papers in this special issue focus on different aspects of vision problem and their management in elderly population. Cataract is one of the major eye pathologies of elderly people. X. Yuan et al. reported the prevalence of astigmatism in eyes requiring cataract surgery. They found that prevalence of astigmatism also increases with age and discussed its implication in visual rehabilitation. L. Zuo et al. discussed the effect of unilateral or bilateral cataract surgery on visual acuity and quality of life in elderly patient. Retinal pigment epithelium (RPE) is involved in various age related pathological changes in the eye including AMD. A. V. Kuznetsova et al. discussed the prospects of using RPE cell line in modelling various pathological changes in human disease and their potential use in retinal repair after ocular pathologies. They also discussed various signaling pathways in RPE which can be used as potential targets for different eye diseases. L. Ottobelli et al. discussed the changes in ocular surface with increasing age and determined the frequency of ocular surface disease (OSD) with age. They concluded that dry eye disease (DED) is the most frequently occurring OSD and its frequency increases with age. A. Sharma and H. B. Hindman reviewed various aspect of DED with the increasing age. Glaucoma is another major cause of vision loss especially in elderly population. Early detection and medical intervention are necessary to control vision loss due to glaucoma. Measurement of anterior chamber angle is an important parameter for diagnosis and management of glaucoma. M. Rigi et al., in this issue, have described a new parameter called TICV (trabecular-iris circumference volume) to detect the health of anterior chamber by optical coherence tomography. N. L. Pratt et al. discussed the relationship between bradycardia and Timolol, a widely used glaucoma medication, and concluded that patients' medical history should be reviewed before prescribing the medication. The study emphasizes the importance of considering full clinical information of patients for deciding treatment regimen taking into account other systemic ailments that the patient is already exposed to or might be predisposed to. Finally, M. Oles and P. Oles discussed the issue of quality of lifestyle in people with low vision especially due to cataract and glaucoma. Their study highlights the importance of social support and task oriented coping to improve quality of life for individuals with low vision. Age related eye diseases, being one of the most prevalent causes of blindness worldwide, demand attention as a global health problem. Research efforts must be concentrated on early detection and cost-effective methods of intervention accessible by people belonging to all economic strata globally. This issue is a small step towards such efforts for prevention of blindness and improving quality of human lives with progression of age. Suddhasil Mookherjee Ashima Bhattacharjee Mainak Sengupta

1 c.1-5G>A NA Novel 1/0 None detected in 25 control individuals 2 c.274G>A p.Val92Met rs2228479 2/0 Associated with both melanoma and nonmelanoma skin cancer 3 c.444C>T p.Tyr148Tyr Novel 1/0 None detected in 25 control individuals 4 c.451C>T p.Arg151Cys rs1805007 1/0 Loss of function variant; associated with both melanoma and nonmelanoma skin cancer 5 c.488G>A p.Arg163Gln rs885479 9/1 Associated with melanoma, nonmelanoma skin cancer, especially basal cell carcinoma 6 c.515G>T p.Ser172Ile Reported mutation 1/0 None detected in 25 control individuals 7 c.699G>A p.Gln233Gln rs146544450 2/0 Not expected to have any biological effect 8 c.942A>G p.Thr314Thr rs2228478 24/2 Not expected to have any biological effect

Nickel based Alloy 617 is one of the leading candidate materials for intermediate heat exchanger (IHX) of the next generation nuclear plant (NGNP). The IHX is anticipated to operate at temperatures between 800 °C and 950 °C, which is in the creep regime. In addition, system start-ups and shut-downs will induce low cycle fatigue (LCF) damages in the IHX components. Hence, designing IHX using Alloy 617 for NGNP construction will require a detailed understanding of the creep-fatigue and ratcheting responses. In this study, a broad set of multiaxial creep-fatigue and ratcheting experiments are performed and the results are critically evaluated. Experiments are conducted by prescribing multiaxial loading histories in axial and shear, stress and strain space at 850 °C and 950 °C with different strain rates and strain amplitudes. Experimental results revealed that the axial strain ratcheting and cyclic hardening/softening responses of Alloy 617 vary significantly with temperature levels, strain rates and strain amplitudes indicating the dependence of creep-fatigue and ratcheting responses on these parameters. A unified constitutive model (UCM) based on the Chaboche framework is developed and validated against the multiaxial experimental responses. UCM simulated responses are compared against the experimental responses for determining the current state of material modeling and if modeling improvement are needed for IHX design applications.

Nickel based Alloy 617 is one of the leading candidate materials for intermediate heat exchanger (IHX) of the next generation nuclear plant (NGNP). The IHX is anticipated to operate at temperatures between 800–950°C, which is in the creep regime. In addition, system start-ups and shut-downs will induce low cycle fatigue (LCF) damages in the IHX components. Hence, designing IHX using Alloy 617 for NGNP construction will require a detailed understanding of the creep-fatigue and ratcheting responses. In this study, a broad set of multiaxial creep-fatigue and ratcheting experiments are performed and the results are critically evaluated. Experiments are conducted by prescribing multiaxial loading histories in axial and shear directions at 850°C and 950°C with different strain rates and strain amplitudes. Experimental results revealed that the axial strain ratcheting and cyclic hardening/softening responses of Alloy 617 vary significantly with temperature levels, strain rates and strain amplitudes indicating the dependence of creep-fatigue and ratcheting responses on these parameters. This necessitates the incorporation of strain rate and strain amplitude dependence and effect of loading non-proportionality and temperature in the unified constitutive modeling (UCM) for a better prediction of the material behavior. Development of a UCM is underway based on the experimental results developed.Copyright © 2013 by ASME

High switching frequency in power electronic converters reduces the size and weight of passive elements used in the converter but increases the switching losses of the power electronic devices. Remedy for high switching losses is the use of soft switching techniques which reduce switching losses and inturn increases efficiency. Zero voltage switching (ZVS) is one type of soft switching technique. In this paper a ZVS strategy based buck converter is presented operated at 50kHz. Performance analysis and simulation of the converter has been done by using SequelGUI2 software. Finally, a small laboratory phototype of rating 50W, 50kHz has been designed, fabricated and tested. The experimental results and simulated performance are found to be in good agreement.

Induction heating is commonly used in the industry for the metal heating, melting, hardening etc. The power converter used is a current source inverter (CSI). High power medium frequency application like melting use thyristor based CSIs, while in medium power and high frequency induction heating application (like surface heat treatment) IGBT based CSIs are increasingly preferred. In this paper simulated and experimental performance of an SCR-based CSI and IGBT based CSI in series cascade (with common dc-link) have been presented. Two laboratory prototypes of rating 2kW, 10kHz each have been fabricated and tested, both individually and then in series cascade. Cascade mode operation of CSIs may find important application in multi-stage surface heat treatment of metals.

Induction motors(IM) are the most popularly used motors in the industry. They come in two well known constructional variations namely, Cage Rotor Induction Motor(CRIM) and Wound Rotor Induction Motor(WRIM). In principle, both the machines are identical, as far as basic running, emf and torque production mechanisms are concerned. But the former has its rotor-bars permanently shorted through end-rings, whereas in case of wound rotor machine, the terminals of the rotor-windings are externally available. WRIMs have been used in variable/adjustable-speed drives for many years. In this paper modeling of a WRIM in different reference frames in real-time simulation has been presented. The model is real-time simulated on a FPGA platform built around an Altera-make Cyclone EPIC12Q240C processor which can be programmed using a software known as Quartus-II.

The Switched Reluctance Motor has a very high torque to weight ratio which can be further increased by using a novel double-sided axial-flux configuration as proposed here. By virtue of its mechanical construction this configuration is suitable for direct wheel drive application. Results of magnetic analysis of and experiments on a laboratory prototype (8/6 pole, 500 VA, 12 Volt, rated 100 RPM) with single-sided-excitation along with hardware set-up is presented here. Experimental results of current chopping, advance angle variation & a speed controller based on voltage control is presented alongside. This novel setup has been fully designed and fabricated, along with power electronic converter, in the laboratory.

Albinism represents a group of genetic disorders with a broad spectrum of hypopigmentary phenotypes dependent on the genetic background of the patients. Oculocutaneous albinism (OCA) patients have little or no pigment in their eyes, skin and hair, whereas ocular albinism (OA) primarily presents the ocular symptoms, and the skin and hair color may vary from near normal to very fair. Mutations in genes directly or indirectly regulating melanin production are responsible for different forms of albinism with overlapping clinical features. In this study, 27 albinistic individuals from 24 families were screened for causal variants by a PCR-sequencing based approach. TYR, OCA2, TYRP1, SLC45A2, SLC24A5, TYRP2 and SILV were selected as candidate genes. We identified 5 TYR and 3 OCA2 mutations, majority in homozygous state, in 8 unrelated patients including a case of autosomal recessive ocular albinism (AROA). A homozygous 4-nucleotide novel insertion in SLC24A5 was detected in a person showing with extreme cutaneous hypopigmentation. A potential causal variant was identified in the TYRP2 gene in a single patient. Haplotype analyses in the patients carrying homozygous mutations in the classical OCA genes suggested founder effect. This is the first report of an Indian AROA patient harboring a mutation in OCA2. Our results also reveal for the first time that mutations in SLC24A5 could contribute to extreme hypopigmentation in humans.

Indians, representing about one-sixth of the world population, consist of several thousands of endogamous groups with strong potential for excess of recessive diseases. However, no database is available on Indian population with comprehensive information on the diseases common in the country. To address this issue, we present Indian Genetic Disease Database (IGDD) release 1.0 (http://www.igdd.iicb.res.in)--an integrated and curated repository of growing number of mutation data on common genetic diseases afflicting the Indian populations. Currently the database covers 52 diseases with information on 5760 individuals carrying the mutant alleles of causal genes. Information on locus heterogeneity, type of mutation, clinical and biochemical data, geographical location and common mutations are furnished based on published literature. The database is currently designed to work best with Internet Explorer 8 (optimal resolution 1440 × 900) and it can be searched based on disease of interest, causal gene, type of mutation and geographical location of the patients or carriers. Provisions have been made for deposition of new data and logistics for regular updation of the database. The IGDD web portal, planned to be made freely available, contains user-friendly interfaces and is expected to be highly useful to the geneticists, clinicians, biologists and patient support groups of various genetic diseases.

Wilson disease (WD) results from accumulation of copper and caused due to mutations in ATP7B, a copper transporting ATPase. Besides regular hepatic and neurological symptoms, WD patients occasionally manifest atypical symptoms due to unknown cause. To understand the molecular etiology of atypical WD manifestations, we screened COMMD1, a gene implicated in canine copper toxicosis, in 109 WD patients including those with atypical symptoms. In a patient showing apoptotic symptoms and high urinary copper surpassing normal WD levels, we identified a novel, putative mutation in COMMD1. Two other changes were also identified in the gene. We have examined genotype-phenotype correlation between the detected changes and the atypical presentation of the WD patient.

Analyses of frequency profiles of markers on disease or drug-response related genes in diverse populations are important for the dissection of common diseases. We report the results of analyses of data on 405 SNPs from 75 such genes and a 5.2 Mb chromosome, 22 genomic region in 1871 individuals from diverse 55 endogamous Indian populations. These include 32 large (>10 million individuals) and 23 isolated populations, representing a large fraction of the people of India. We observe high levels of genetic divergence between groups of populations that cluster largely on the basis of ethnicity and language. Indian populations not only overlap with the diversity of HapMap populations, but also contain population groups that are genetically distinct. These data and results are useful for addressing stratification and study design issues in complex traits especially for heterogeneous populations.

This paper proposes an averaged dynamic model of a permanent magnet synchronous motor (PMSM) exhibiting sinusoidal flux distribution, while fed from a two-level voltage source inverter (VSI), operating in 120deg conduction mode. This averaged model is formulated in the light of a conventional permanent magnet DC motor with mechanical commutator and is found similar. A "Detailed Numerical Model", which is totally numerical in nature and which more accurately models the inverter device switchings of 120deg conduction mode, is initially developed. The results, predicted by this model are first validated against experiments done on a laboratory prototype PMSM, developed in recent past, which nearly exhibits a sinusoidal back EMF distribution. They are found to match closely. Thereafter, the results predicted by the proposed averaged dynamic model are compared against those predicted by the 'Detailed Numerical Model' under identical operating conditions. The results are found to be close and are presented.

Oculocutaneous albinism (OCA) is an autosomal recessive disorder of melanin biosynthesis that results in congenital hypopigmentation of ocular and cutaneous tissues. It is also associated with common developmental abnormalities of the eye. Mutations in the solute carrier family 45, member 2 gene (SLC45A2, also called MATP) cause oculocutaneous albinism type 4 (OCA4), which is the second most prevalent type of OCA in Japan. So far, 24 pathological mutations have been reported in SLC45A2, but there is no report from India. Interestingly, in almost 31% of the cases, the second mutation has never been found. The purpose of this study was to investigate the molecular basis of OCA among Indians using SLC45A2 as the candidate gene.From our patient pool, consisting of 50 unrelated OCA pedigrees covering 17 ethnic groups of eastern and southern India, 20 patients (from 19 affected families) lacking any mutation in the tyrosinase gene (TYR) were screened further for nucleotide variants in SLC45A2. All seven exons and splice-site junctions of SLC45A2 were amplified and sequenced from the OCA patients and from 50 ethnically matched healthy controls. Nucleotide changes were detected by identifying 'double peaks' in the chromatogram due to heterozygosity as well as by pairwise BLAST analysis of the sequence output data with a normal copy of SLC45A2. Haplotype analysis was done among the affected sibs using three newly identified microsatellite markers placed within and in flanking regions of the SLC45A2 locus.Four novel mutations (c.126GA [Met42Ile], c.190GA [Gly64Ser], c.904AT [Thr302Ser], and c.1042CT [Arg348Cys]) and one reported mutation (c.469GA [Asp157Asn]) were identified in SLC45A2. All the novel changes cosegregated with the disease and none were present in control samples. Consistent with previous reports, we did not find the second mutant allele in three unrelated patients. Haplotype analysis using microsatellite markers in the family of one such proband suggested that the affected sibs inherited the mutant allele (Arg348Cys) from their father but different SLC45A2 alleles from the mother. In addition, five single nucleotide variants were identified which included E272K and L374F polymorphisms that have been reported to be associated with human ethnicities.Our study reveals that 10% of the total OCA cases from eastern and southern Indian ethnic groups carry mutations in SLC45A2. Among 10 variants found in the gene, five are pathogenic changes. Our data, based on haplotype analysis on a single family, suggest that the disease is caused in the affected sibs either by a single mutation in SLC45A2 and a defect in another locus, or SLC45A2 is not responsible for the disorder in the family, but the pathogenesis is caused by a mutation in another gene not yet characterized in these patients.

The static synchronous compensator (STATCOM) is becoming increasingly popular in power system applications. Through reactive power compensation, supply side power factor at point of common coupling (PCC) can be improved to almost unity. The highlight of the present work is the practical implementation of such a scheme on a 10 kVA STATCOM laboratory prototype fabricated for the purpose. The linear model of the STATCOM is discussed, in which the current and DC–link voltage controllers have been separately designed. The performance of all the designed controllers are first simulated and then experimentally validated as mentioned. Excellent agreement between the simulated and experimental results demonstrates the effectiveness of the proposed control strategy.

This paper presents the implementation of the indirect space vector pulse width modulation (SVPWM) control method of a three-phase ac-ac matrix converter using TMS320LF2407A DSP. The control scheme calculates duty cycles in real time and generates corresponding logic level signals. The SVPWM signals for nine bi-directional switch module in a matrix converter are also generated in encoded form. The pulses are distributed to respective switches at each sampling interval with the help of a combinational logic implemented through a FPGA used for generating current commutation logic pulses. The SVPWM signals for a particular sampling interval and the encoded signals at each sampling period are shown.

Matrix converter, which is essentially a forced commutated cycloconverter, has most of the desirable features for any power frequency changers like simple and compact power circuits, generation of load voltage with arbitrary amplitude and frequency, sinusoidal input and output currents, adjustable power factor for any load, regeneration capability and harmonics reduction. A critical issue in control of this converter is current commutation as no freewheel path is available for the load current. In this paper, FPGA implementation of a semi-soft four-step commutation technique based on output current direction in matrix converter is presented. The same program can be used for implementing a three-step commutation process. A universal and synchronous commutation scheme for all the IGBTs is devised so that commutation can smoothly take place as and when required within the minimum possible time depending on the switching times of the IGBT used. The program logic is tested with the program simulator under various critical conditions.

An important assumption made in the performance analysis of SRM under saturation (bulk saturation) is that the MMF spent in the iron parts is dependent only on the average flux level and not on the rotor position. The predicted static torque versus position characteristics show good agreement with experimental characteristics up to moderate values of exciting currents. For larger currents they differ by a considerable amount from the experimental results. This leads to the conjecture that the pole-body and more predominantly the pole-tip saturation (local saturation) effects may be significant. However the average torque per stroke is quite accurately determined from the consideration of bulk saturation alone being present. To evaluate the extra torque due to local saturation an analytical model is proposed and the extra torque for each rotor position is determined in this paper using a semianalytical method. This is added to the torque obtained using the analytical model proposed for bulk saturation in a previous work. It is found that this new composite model, gives a static torque characteristic which is similar in nature to the experimental torque obtained but optimistic everywhere. The discrepancy can be attributed to the nonavailability of the exact B-H data of the material used for the stator/ rotor laminations of the tested machine and noninclusion of iron losses in this model.

Background OCA is a group of autosomal recessive disorders characterized by hypopigmentation and abnormalities related to ocular development. Mutations in genes regulating melanin-biosynthesis cause four classical types of OCA (OCA 1-4). The clinical spectrum of OCA often depends on the pigmentation threshold of a patient, highlighting the importance of ethnicspecific SNPs. We aimed to understand the molecular bases of OCA in India, where it is one of the four major causes of childhood blindness.

A simple and reasonably accurate method of predicting the performance of a SR motor under saturated condition directly from its design data is presented. First, the L-/spl theta/ and dL/d/spl theta/-/spl theta/ curves under unsaturated conditions have been obtained using an approximate analytical method originally proposed by Pohl for inductor alternators in 1946. The method takes into consideration the slot fringing flux but is easier to apply, if not as exact, as compared to the conformal mapping technique. Assuming the ampere-turns for the iron parts of the machine to be dependent only on the total flux, a very simple method of calculating the torque developed under saturation conditions is presented and is used to obtain the static torque against rotor position and the torque-speed characteristics of the motor. Finally, a method for online measurement of unsaturated phase inductance has been developed and is used to switch different phases of the motor sequentially without the need for a shaft mounted position sensor. The theory developed has been applied for the prediction of the performance of a small SR motor designed and fabricated locally as well as that of a commercially available motor.

Power factor on the supply side at point of common connection (PCC) can be improved through reactive power compensation using a static synchronous compensator (STATCOM). This approach is becoming increasingly popular in power system applications. In this paper, a small signal model of the STATCOM is practically implemented for maintaining unity power factor on the grid side in presence of inductive loads using a 10 kVA laboratory prototype. The designed controller is first simulated and then experimentally validated on the above laboratory prototype. Excellent agreement between the simulated and experimental results demonstrates the effectiveness of the proposed control strategy and highlights the accuracy of the experiments.

This paper presents a case study on the effects of inclusion of Static VAR Compensator (SVC) and Thyristor Controlled Series Compensator (TCSC) on the impedances seen by different relays, present in a power system, under a variety of loading conditions. Newton-Raphson method-based load-flow program has been developed using existing standard software packages in which models of SVC as well as TCSC have been incorporated. A 5-bus and 7-line system ([1], [2]) has been examined with the developed program and the results have been presented through appropriate figures and tables. The system performance under no-compensation, after SVC connection and after TCSC connection have been compared.

Linear induction motors (LIMs) have got potential to replace the age old belt-pulley driven systems and the likes, which are in use for conversion of rotary to linear motion in most of the applications. In the present work a 3-phase, 50 Hz, 4-pole, 220 V, 320 W, 2.5 m/s LIM has been designed, fabricated and successfully tested on a test track. 2-D finite element analysis of the LIM has been done with ANSYS 7.1 to evaluate typical field and circuit variables. The results are in good agreement with the analytical as well as experimental values.

The power and control circuits required for the running of a 4 kW switched reluctance motor (SRM) are presented in this paper along with their design, fabrication and testing. Among the various existing configurations, single switch per phase with split DC link configuration is used. The control signal is generated by TMS320LF2407A DSP controller. The whole scheme-along with the IGBT-based power converter, the driver modules, the protection, sensing and interfacing circuits-has been designed, fabricated, tested module-wise and is implemented on a 4 kW, 4 phase, 300 V, 1500 RPM Oulton make SRM.