864 research outputs found

    Simulation of old open clusters for UVIT on ASTROSAT

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    Ultra Violet Imaging Telescope (UVIT) is one of the payloads on the first Indian multi wavelength satellite ASTROSAT expected to be launched by Indian Space Research Organisation (ISRO) in the year 2015. We have performed simulations of UV studies of old open clusters for the UVIT. The colour magnitude diagrams (CMDs) and spatial appearances have been created using 10 filters of FUV channel (130 - 180 nm) and NUV channel (200 - 300nm) available for observations on the UVIT, for three old open clusters M67, NGC 188 and NGC 6791. The CMDs are simulated for different filter combinations, and they are used to identify the loci of various evolutionary sequences, white dwarfs, blue stragglers, red giants, sub giants, turn off stars and the main sequence of the clusters. The present work helps in identifying the potential area of study in the case of three old open clusters, by considering the availability of filters and the detection limits of the instrument. We also recommend filter combinations, which can be used to detect and study the above mentioned evolutionary stages. The simulations and the results presented here are essential for the optimal use of the UVIT for studies of old open clusters.Comment: Accepted for publication in RAA; 25 pages, 19 figures, 1 tabl

    An Improvements of Deep Learner Based Human Activity Recognition with the Aid of Graph Convolution Features

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    Many researchers are now focusing on Human Action Recognition (HAR), which is based on various deep-learning features related to body joints and their trajectories from videos. Among many schemes, Joints and Trajectory-pooled 3D-Deep Geometric Positional Attention-based Hierarchical Bidirectional Recurrent convolutional Descriptors (JTDGPAHBRD) can provide a video descriptor by learning geometric features and trajectories of the body joints. But the spatial-temporal dynamics of the different geometric features of the skeleton structure were not explored deeper. To solve this problem, this article develops the Graph Convolutional Network (GCN) in addition to the JTDGPAHBRD to create a video descriptor for HAR. The GCN can obtain complementary information, such as higher-level spatial-temporal features, between consecutive frames for enhancing end-to-end learning. In addition, to improve feature representation ability, a search space with several adaptive graph components is created. Then, a sampling and computation-effective evolution scheme are applied to explore this space. Moreover, the resultant GCN provides the temporal dynamics of the skeleton pattern, which are fused with the geometric features of the skeleton body joints and trajectory coordinates from the JTDGPAHBRD to create a more effective video descriptor for HAR. Finally, extensive experiments show that the JTDGPAHBRD-GCN model outperforms the existing HAR models on the Penn Action Dataset (PAD)

    Performance Evaluation of Quarter Shift Dual Tree Complex Wavelet Transform Based Multifocus Image Fusion Using Fusion rules

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    In this paper, multifocus image fusion using quarter shift dual tree complex wavelet transform is proposed. Multifocus image fusion is a technique that combines the partially focused regions of multiple images of the same scene into a fully focused fused image. Directional selectivity and shift invariance properties are essential to produce a high quality fused image. However conventional wavelet based fusion algorithms introduce the ringing artifacts into fused image due to lack of shift invariance and poor directionality. The quarter shift dual tree complex wavelet transform has proven to be an effective multi-resolution transform for image fusion with its directional and shift invariant properties. Experimentation with this transform led to the conclusion that the proposed method not only produce sharp details (focused regions) in fused image due to its good directionality but also removes artifacts with its shift invariance in order to get high quality fused image. Proposed method performance is compared with traditional fusion methods in terms of objective measures.

    Acculturation and oral health status among Tibetan immigrants residing in Bangalore City, India

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    Background: This study is the first of its kind conducted among Tibetans immigrants to Bangalore City, India to study the effects of acculturation on the oral health outcomes of less established group of individuals. Objectives: To determine the Acculturation and oral health status among Tibetan immigrants in Bangalore city and to assess the relationship between them. Materials and Methods: A random sample of 560 immigrants aged 18 years and above from different Tibetan centre of Bangalore city were included for the study. Acculturation was measured using modified Psychological-behavioral acculturation scale. Dental caries experience and periodontal status were recorded. Results: 49.1% of females and 50.9% of males were in highly accultured group. Bivariate analysis using Chi-square test was performed using 5% significance level. Logistic regression analysis demonstrated a strong association between DMFT and Ethnic factors, and periodontal status with language barrier and utilization of health care. Discussion: Reducing disparities in oral health status and in the use of dental services among Tibetan immigrants require attention to cultural factors such as language barrier and age at migration and immigrant’s degree of acculturation

    Nanomaterials and Nanotechnologies for Marine and Membrane Antifouling Applications

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    The major responsibility of the marine industry includes the global transportation of goods, materials, and people. To cater the longstanding challenges like degradation of materials and biofouling, it has embraced nanotechnology solutions. Nano-technology offered numerous products such as nano-ZnO, nano alumina, and nano silica, etc. to deal with corrosion in a cost-effective manner. Similarly, to address the biofouling in the aquatic environment, hybrid nanocomposites of organic-inorganic materials, photocatalytic nanomaterials, metal and metal oxide nanomaterials (nanoparticles, nanowires, nanorods), etc. are employed as viable agents to create non-toxic or low-toxic antifouling coatings. On the other hand, membrane separation technology plays a significant role in various industries including water treatment plants, food, medicine, pharmacy, biotechnology, etc. in addition to the domestic arena for the purification of drinking water. Such a wonderful technology is being totally disturbed by a troublesome problem and a predominant barrier called membrane fouling, which drastically limits the commercialization of the membranes and the whole membrane industrial technology as well. Hence, this review exclusively throws light on the role of nanomaterials and nanotechnologies developed for the prevention of fouling that occurs on submerged structures and membranes as well and to give possible solutions with increased resilience against challenges to come

    The rs12255372(G/T) and rs7903146(C/T) polymorphisms of the TCF7L2 gene are associated with type 2 diabetes mellitus in Asian Indians

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    One thousand thirty-eight normal glucose-tolerant and 1031 type 2 diabetic subjects selected from the Chennai Urban Rural Epidemiology Study were genotyped using polymerase chain reaction-restriction fragment length polymorphism assay to investigate the association of rs12255372(G/T) and rs7903146(C/T) polymorphisms of the transcription factor 7–like 2 (TCF7L2) gene with type 2 diabetes mellitus in Asian Indians. The frequency of the “T” allele of both rs12255372(G/T) and rs7903146(C/T) polymorphisms was significantly higher in diabetic subjects (23% and 33%) compared to that in normal glucose-tolerant subjects (19% and 28%; P = .001 and P = .0001, respectively). Logistic regression analysis of the rs12255372(G/T) polymorphism showed that the odds ratio (adjusted for age, sex, and body mass index) was 1.56 (95% confidence interval [CI], 1.03-2.37; P = .034) for the TT genotype and 1.29 (95% CI, 1.06-1.58; P = .011) for the TG genotype when compared with the GG genotype. Adjusted odds ratios for the TT and TC genotypes of the rs7903146(C/T) polymorphism were found to be 1.50 (95% CI, 1.08-2.08; P = .013) and 1.44 (95% CI, 1.18-1.76; P = .0003), respectively, compared with the CC genotype. Normal glucose-tolerant subjects with the TT genotype of rs12255372(G/T) had significantly higher 2-hour plasma glucose levels (mean ± SD, 6.1 ± 1.4 mmol/L) than those with the GG genotype (5.6 ± 1.0 mmol/L, P = .011). Normal glucose-tolerant subjects with the TT genotype of rs7903146(C/T) polymorphism had significantly higher 2-hour plasma glucose levels (mean ± SD, 6.0 ± 1.3 mmol/L) than those with the CC genotype (5.6 ± 1.0 mmol/L, P = .004). In conclusion, the T allele of the rs12255372(G/T) and rs7903146(C/T) polymorphisms of TCF7L2 gene confer susceptibility to type 2 diabetes mellitus in Asian Indians. © 2007 Elsevier Inc. All rights reserved

    Diabetic eye screening in multi ethnic population of Malaysia: epidemiological risk factors for development of diabetic retinopathy

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    Background:The objective of this study is to evaluate epidemiological risk factors for development of diabetic retinopathy.Methods:The cases of type-2 diabetes mellitus attending Melaka Manipal medical college, Malaysia were retrospectively reviewed. The epidemiological characteristics of diabetic retinopathy were estimated. The cases were graded according to degree of retinopathy in to: non-diabetic retinopathy group and diabetic retinopathy. Clinical and biochemical studies were used for studying the risk factors associated with development of retinopathy.Results:The prevalence of diabetic retinopathy in the population was 21% in known diabetic subjects and was significantly higher in men than in women (21.3% vs. 14.6%) with increasing age and duration of diabetes. Ethnicity is a complex, independent risk factor for diabetic retinopathy. Sight threatening diabetic retinopathy, and clinically significant macular edema was higher in people of Malaysia (20%) when compared with Chinese (16%) and Indonesians (12%). In all, 55 percent of patients with known diabetes mellitus had never undergone an eye examination. Among patients who had undergone eye examinations, 32.8 percent had the last examination within the last one year, 49.8 percent within the last one to two years, and 17.4 percent more than two years ago.Conclusion:Diabetic retinopathy is highly prevalent in the patients with type-2 diabetes mellitus in Malaysia. Besides blood glucose, many factors are associated with the present and development of diabetic retinopathy.
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