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The emergence of new technologies, such as whole genome sequencing systems, which generate a large amount of data, is requiring ultrahigh storage capacities. Due to their compactness and low power consumption, probe-based memory devices using Pb(Zr(0.2)Ti(0.8))O(3) (PZT) ferroelectric films are the ideal candidate for such applications where portability is desired. To achieve ultrahigh (>1 Tbit/in(2)) storage densities, sub-10 nm inverted domains are required. However, such domains remain unstable and can invert back to their original polarization due to the effects of an antiparallel built-in electric field in the PZT film, domain-wall, and depolarization energies. Here, we show that the built-in electric-field can be tuned and suppressed by repetitive hydrogen and oxygen plasma treatments. Such treatments trigger reversible Pb reduction/oxidation activity, which alters the electrochemistry of the Pb overlayer and compensates for charges induced by the Pb vacancies. This tuning mechanism is used to demonstrate the writing of stable and equal size sub-4 nm domains in both up- and down-polarized PZT films, corresponding to eight inverted unit-cells. The bit sizes recorded here are the smallest ever achieved, which correspond to potential 60 Tbit/in(2) data storage densities.

Aim: Allergic diseases are increasing alarmingly worldwide affecting >30% of the population, including India. Allergy is the result of interaction of the epitopes on the protein with the immunoglobulin E (IgE). T helper cell-2 cytokines promote allergen-specific IgE antibody and induce eosinophil-dominated inflammatory tissue responses. Interleukin-10 (IL-10), an antiinflammatory cytokine, plays a major role in the development of the allergy. The cytokine gene polymorphism of -592C→A (rs1800872) and -1082G→A (rs1800896) of IL-10 may influence the expression of the protein. Hence, the current study was aimed to evaluate the persistent association between these variants in the susceptibility of the disease., Methods: The allelic and genotype frequencies corresponding to IL-10 (-592C→A; -1082G→A) were determined in 94 allergic patients and 100 controls. Genomic typing was performed with polymerase chain reaction with sequence-specific primers., Result: The genotype AA at -592 position (p<0.000; odds ratio [OR] 9.92; 95% confidence interval [CI]=5.06-19.42) and GG at IL-10-1082 position (p<0.04; OR=2.47; 95% CI=1.003-4.96) was associated significantly in patients compared with controls. A considerable frequency of A-A haplotype in the patients and C-A, C-G haplotypes in controls was observed. A highly noteworthy difference was found in diplotype frequencies of A/A-A/A and A/A-G/A in patients and A/C-G/G and A/C-G/A in the controls., Conclusion: Our results indicate that haplotype and diplotype frequencies of the IL-10 locus may confer susceptibility to allergic patients.

Traditionally, the distribution of the Mycobacterium tuberculosis genotypes in India has been characterized by widespread prevalence of ancestral lineages (TbD1+ strains and variants) in the south and the modern forms (TbD1(-) CAS and variants) predominating in the north of India. The pattern was, however, not clearly known in the south-central region such as Hyderabad and the rest of the state of Andhra Pradesh where the prevalence of both tuberculosis (TB) and human immunodeficiency virus (HIV) infection is one of the highest in the country; this area has been the hotspot of TB vaccine trials. Spoligotyping of 101 clinical isolates obtained from Hyderabad and rural Andhra Pradesh confirmed the occurrence of major genogroups such as the ancestral (or the TbD1+ type or the East African Indian (EAI) type), the Central Asian (CAS) or Delhi type and the Beijing lineage in Andhra Pradesh. Sixty five different spoligotype patterns were observed for the isolates included in this study; these were further analyzed based on specific genetic signatures/mutations. It was found that the major genogroups, CAS and "ancestral," were almost equally prevalent in our collection but followed a north-south compartmentalization as was also reported previously. However, we observed a significant presence of MANU lineage in south Andhra Pradesh, which was earlier reported to be overwhelmingly present in Mumbai. This study portrays genotypic diversity of M. tuberculosis from the Indian state of Andhra Pradesh and provides a much needed snapshot of the strain diversity that will be helpful in devising effective TB control programs in this part of the world.

Probe-based memory devices using ferroelectric media have the potential to achieve ultrahigh data-storage densities under high write-read speeds. However, the high-speed scanning operations over a device lifetime of 5-10 years, which corresponds to a probe tip sliding distance of 5-10 km, can cause the probe tip to mechanically wear, critically affecting its write-read resolution. Here, we show that the long distance tip-wear endurance issue can be resolved by introducing a thin water layer at the tip-media interface-thin enough to form a liquid crystal. By modulating the force at the tip-surface contact, this water crystal layer can act as a viscoelastic material which reduces the stress level on atomic bonds taking part in the wear process. Under our optimized environment, a platinum-iridium probe tip can retain its write-read resolution over 5 km of sliding at a 5 mm/s velocity on a smooth ferroelectric film. We also demonstrate a 3.6 Tbit/inch(2) storage density over a 1 × 1 μm(2) area, which is the highest density ever written on ferroelectric films over such a large area.

Objective: Pulmonary tuberculosis (PTB) is a leading cause of morbidity and mortality. Macrophages play an important role in the immunopathogenesis of tuberculosis. Extracellular ATP induces macrophage bactericidal activity through activation of the purinergic P2X7 receptor. This case- control study assesses the association of -762 T/C, 1513A/C and 1729T/A P2X7 polymorphisms in patients with PTB and healthy controls to establish association if any with risk of developing the disease., Materials and Methods: The genotyping for P2X7 was carried out using PCR and RFLP analysis in 256 individuals, which included 156 active PTB patients and 100 age and sex, matched healthy volunteers with no clinical symptoms or family history of PTB as controls., Results: A chi square test showed a significant difference between the PTB patient and controls for -762 C allele; p=0.0051 (OR 1.6972, CI 95% 1.1839 to 2.4332) and 1729 T allele was found to be positively associated with the PTB; p < 0.0005 (OR- 2.4623, CI 95% 1.6376 to 3.7022). 1513A/C polymorphism did not show any significant difference between the two groups., Significance: The study revealed a significant association of P2X7-762C allele and P2X7 1729T allele receptor polymorphisms with PTB in Asian Indian population. The use of these alleles as biomarkers for identifying individuals at high risk of developing TB needs to be ascertained.

A latex polymer of styrene-acrylic acid emulsion is used as a template for the synthesis of novel porous nanosilica (PNS) material. TiO(2) is dispersed over PNS by solid state dispersion and the composite materials are characterized by XRD, nitrogen adsorption-desorption isotherms, SEM and TEM measurements. The photocatalytic activities of the composite TiO(2)/PNS catalysts are evaluated for degradation of isoproturon pesticide in water with different parameters under solar light. Furthermore, commercial pesticide solutions containing imidacloprid and phosphamidon were also degraded successfully with the composite system using the same developed conditions for isoproturon degradation. The 5 wt% TiO(2)/PNS is found to be active in the present investigation.

The photocatalytic degradation and mineralization of isoproturon herbicide was investigated in aqueous solution containing TiO2 over H-mordenite (H-MOR) photocatalysts under solar light. The catalysts are characterized by X-ray diffraction (XRD), UV-Vis diffused reflectance spectra (UV-Vis DRS), Fourier transform-infra red spectra (FT-IR) and scanning electron microscopy (SEM) techniques. The effect of TiO2, H-MOR support and different wt% of TiO2 over the support on the photocatalytic degradation and influence of parameters such as TiO2 loading, catalyst amount, pH and initial concentration of isoproturon on degradation are evaluated. 15wt% TiO2/H-MOR composite is found to be optimum. The degradation reaction follows pseudo-first order kinetics and is discussed in terms of Langmuir-Hinshelwood (L-H) kinetic model. The extent of isoproturon mineralization studied with chemical oxygen demand (COD) and total organic carbon (TOC) measurements and approximately 80% mineralization occurred in 5h. A plausible mechanism is proposed based on the intermediates identified by liquid chromatography-mass spectroscopy (LC-MS).

The present study was designed to analyze the distribution of HLA DQ B1* and DR B1* in patients with goitrous juvenile autoimmune hypothyroidism from Hyderabad, India. Analysis indicated an increase in the frequencies of HLA DQ B1* 03 allele (P < 0.000) and HLA DR B1* 04 (P < 0.05) alleles in this group of patients when compared to the controls, whereas the frequency of DQB1* 05 was found to be decreased in patients' group compared to the controls (p < 0.01). To conclude, we report a positive correlation between DQ B1* 03 and DR B1* 04 and goitrous juvenile autoimmune hypothyroidism, whereas DQB1* 05 is observed to be negatively correlated with this thyroid dysfunction. Since the disease-susceptible HLA class II alleles appear to differ in various ethnic groups for some autoimmune diseases, the observed association from Indian series of patients holds significance.

Background: Mycobacterium bovis BCG vaccine has displayed inconsistent efficacy in different trials conducted in various geographical regions. Nevertheless, it significantly reduces the risk of severe childhood tuberculosis and continues to be used to prevent tuberculosis in many countries. Many studies revealed that efficacy of vaccine wanes with age. Most of the studies were based on in vivo and in vitro responses to tuberculin. With the advent of newer tests such as in vitro interferon-gamma assays and identification of potent immunogenic mycobacterial proteins there is a need to corroborate the observations. This study aims at ascertaining the need for a booster at a later age as indicated by in vitro release of IFN-gamma while evaluating Ag85A as an antigen., Methods: Ninety healthy children who were without any clinical evidence of the disease, 45 with a BCG-scar and the remaining 45 without scar and 25 with tuberculosis were included in the study. The incidence of TB was analyzed in 216 children attending a DOTS clinic during 1996-2005. CD3+, CD4+ and CD8+ cell counts were measured by Flow cytometry. r32kDaBCG (Ag85A-BCG) protein was used to stimulate T cells in in vitro T cell responses and interferon-gamma (IFN-gamma) cytokine levels in the supernatants were measured by ELISA., Results: High incidence of TB was observed in age group 13-14 years followed by children in the age group 10-12 years (Chi-square 242.22; p < 0.000). T cell subsets were within the normal range in all subjects. 79% of vaccinated children showed positive proliferative responses with a mean SI value of 4.98 +/- 1.99 while only 39% of the unvaccinated and 58% of the tuberculosis children showed positive responses with mean values of 2.9 +/- 1.6 (p < 0.001) and 2.9 +/- 1.7(p < 0.057), respectively. The stimulation indices in vaccinated children decreased in the older children concurring with an increase in the incidence of TB., Conclusion: Significantly high levels of in vitro IFN-gamma demonstrated in BCG vaccinated children in our study substantiate the observation that BCG is effective in children, but the effect may wane with age. The immunity could be boosted using modified r32kDa (Ag85A) of BCG.

Cytokines play a crucial role in the pathogenesis of autoimmune thyroid disease. The aim of this study was to investigate the relationship of the single base change polymorphic variants identified in the first intron of interferon-gamma (IFN-gamma) (+874 T/A) with susceptibility to thyroid dysfunctions. A total of 340 subjects were included in the study comprising of 190 patients (104 patients with Hashimoto's thyroiditis, 26 with non-Hashimoto's hypothyroidism and 60 Graves' disease) and 150 controls. Genotyping was done by amplification refractory mutation system-polymerase chain reaction using a set of sequence-specific primers. Statistical analysis revealed a significant association between high IFN-gamma-producing genotype TT and Hashimoto's thyroiditis compared to controls (P value < 0.001). On the other hand, the frequency of genotype TT was decreased in patients with Graves' hyperthyroidism with a significant increase in low IFN-gamma-producing genotype AA among this group (P = 0.03). To conclude the results of the study suggest a differential association of high- and low-producing alleles of IFN-gamma gene with Hashimoto's thyroiditis and Graves' disease. The high IFN-gamma-producing allele T was observed to be associated with Hashimoto's thyroiditis in the present study where as in Graves' hyperthyroidism the association was observed to be stronger with the low producing allele A.

The high degree of polymorphism of the human leukocyte antigen (HLA) system provides means for the study of diversity in different populations. The aim of this work is to study the HLA phenotype frequencies in the United Arab Emiratis in comparison with other geographically related Arabs, Iranians, and Asians, all living in the United Arab Emirates (UAE). Healthy blood donors and potential kidney or bone marrow donors were typed for HLA class I (n = 1880) and class II (n = 2022). Only one representative member of each family was included to avoid bias. UAE Emiratis, Arabs of Arabian Gulf Peninsula (AGP), Arabs of South Mediterranean (SMR), North African Arabs (NA), Iranians, and Asians. HLA typing was done by microlymphocytotoxicity method and/or low-resolution polymerase chain reaction-sequence-specific primer techniques. As an individual antigen, HLA-A2 had the highest frequency in all populations studied, however, the frequency of the broad antigen A19 surpassed A2 in all the groups except the AGP Arabs and Iranians. B5 was the predominant B antigen in all groups except the SMR and Asians. Amongst the class II broad antigens, DR2 was the most frequent antigen in UAE, AGP Arabs, Iranians, and Asians. The overall frequency of DQ1 was high in all groups except the SMR Arabs who had an almost equal distribution of DQ1 and DQ3. In conclusion, this study indicates that the most frequent antigens in the UAE population are HLA-A19, HLA-A2, HLA-B5, and HLA-DR2. It also sheds light on the similarities between the UAE Emiratis, AGP Arabs, Iranians, and Asians, specially the predominance of DR2 of the class II antigens.