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The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
Epidemiological studies indicate that individuals with one type of mental disorder have an increased risk of subsequently developing other types of mental disorders. This study aimed to undertake a comprehensive analysis of pair-wise lifetime comorbidity across a range of common mental disorders based on a diverse range of population-based surveys.
The WHO World Mental Health (WMH) surveys assessed 145 990 adult respondents from 27 countries. Based on retrospectively-reported age-of-onset for 24 DSM-IV mental disorders, associations were examined between all 548 logically possible temporally-ordered disorder pairs. Overall and time-dependent hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models. Absolute risks were estimated using the product-limit method. Estimates were generated separately for men and women.
Each prior lifetime mental disorder was associated with an increased risk of subsequent first onset of each other disorder. The median HR was 12.1 (mean = 14.4; range 5.2–110.8, interquartile range = 6.0–19.4). The HRs were most prominent between closely-related mental disorder types and in the first 1–2 years after the onset of the prior disorder. Although HRs declined with time since prior disorder, significantly elevated risk of subsequent comorbidity persisted for at least 15 years. Appreciable absolute risks of secondary disorders were found over time for many pairs.
Survey data from a range of sites confirms that comorbidity between mental disorders is common. Understanding the risks of temporally secondary disorders may help design practical programs for primary prevention of secondary disorders.
National Vector Borne Disease Control Programme (NVBDCP) data have shown that nearly half of all malaria deaths in India occur in tribal-dominated areas. The present study took a qualitative approach to understanding community perceptions and practices related to malarial infection and anti-malarial programmes. Twelve focus group discussions and 26 in-depth interviews of Accredited Social Health Activists (ASHAs) were conducted in nine villages in the district of Gadchiroli, Maharashtra state in India in June 2016. A total of 161 village residents (94 males and 67 females) participated in the focus group discussions and 26 health workers participated in the in-depth interviews. Data were analysed using the content analysis approach. The findings revealed widespread misconceptions about malaria among village residents, and low use of preventive measures and anti-malarial services. Ignorance and treatment by unqualified traditional healers delay effective treatment seeking. Furthermore, failure to maintain drug compliance adds to the gravity of the problem. The study identified the social and behavioural factors affecting treatment uptake and use of treatment facilities in the study area. These should help the development of the behavioural change communication arm of any control strategy for malaria through improving community participation, so improving preventive practices and optimizing utilization of anti-malarial services.
Agriculture in the Central Himalayan Region depends on the availability of suitable germplasm as well as natural conditions. Due to extreme weather conditions, food and nutrition security is a major issue for communities inhabiting these remote and inaccessible areas. Millets are common crops grown in these areas. Foxtail millet (Setaria italica (L.) P. Beauv) is an important crop and forms a considerable part of the diet in this region. The aim of the present study was to explore, collect, conserve and evaluate the untapped genetic diversity of foxtail millet at the molecular level and discover variability in their nutritional traits. A total of 30 accessions having unique traits of agronomic importance were collected and molecular profiling was performed. A total of 63 alleles were generated with an average of 2.52 alleles per locus and average expected heterozygosity of 0.37 ± 0.231. Significant genetic variability was revealed through the genetic differentiation (Fst) and gene flow (Nm) values. Structure-based analysis divided whole germplasm into three sub-groups. Rich variability was found in nutritional traits such as dietary fibre in husked grains, carbohydrate, protein, lysine and thiamine content. The collected germplasm may be useful for developing nutritionally rich and agronomically beneficial varieties of foxtail millet and also designing strategies for utilization of unexploited genetic diversity for food and nutrition security in this and other similar agro-ecological regions.
Although there is robust evidence linking childhood adversities (CAs) and an increased risk for psychotic experiences (PEs), little is known about whether these associations vary across the life-course and whether mental disorders that emerge prior to PEs explain these associations.
We assessed CAs, PEs and DSM-IV mental disorders in 23 998 adults in the WHO World Mental Health Surveys. Discrete-time survival analysis was used to investigate the associations between CAs and PEs, and the influence of mental disorders on these associations using multivariate logistic models.
Exposure to CAs was common, and those who experienced any CAs had increased odds of later PEs [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.9–2.6]. CAs reflecting maladaptive family functioning (MFF), including abuse, neglect, and parent maladjustment, exhibited the strongest associations with PE onset in all life-course stages. Sexual abuse exhibited a strong association with PE onset during childhood (OR 8.5, 95% CI 3.6–20.2), whereas Other CA types were associated with PE onset in adolescence. Associations of other CAs with PEs disappeared in adolescence after adjustment for prior-onset mental disorders. The population attributable risk proportion (PARP) for PEs associated with all CAs was 31% (24% for MFF).
Exposure to CAs is associated with PE onset throughout the life-course, although sexual abuse is most strongly associated with childhood-onset PEs. The presence of mental disorders prior to the onset of PEs does not fully explain these associations. The large PARPs suggest that preventing CAs could lead to a meaningful reduction in PEs in the population.
Urinary tract infection (UTI) is common in children aged <5 years with diarrhoea, but little is known about risk factors, aetiology and outcome of such children. We aimed to evaluate these knowledge gaps of UTI in children aged <5 years with diarrhoea. We enrolled all children aged <5 years with diarrhoea admitted to Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, between May 2011 and April 2013, who had history of fever (⩾38 °C) and obtained a urine sample for culture. Diarrhoea with UTI (confirmed by culture) constituted cases (n = 26) and those without UTI constituted controls (n = 78). Threefold controls were randomly selected. The case-fatality rate was comparable in cases and controls (4% vs. 1%, P = 0·439). Escherichia coli (69%) and Klebsiella (15%) were the most commonly isolated pathogens. Persistent diarrhoea, pneumonia and prior antibiotics use were identified as risk factors for UTI in logistic regression analysis (P < 0·05 for all). Thus, children with diarrhoea presenting with persistent diarrhoea, pneumonia, and prior antibiotic use should be investigated for UTI for their prompt management that may reduce morbidity.
The Proterozoic Sushina Hill Complex is the only agpaitic complex, reported from India and is characterized by a eudialyte-rinkite-bearing nepheline syenite. The complex is considered a ‘metamorphosed agpaitic complex'. This study describes the mineral assemblages formed during successive stages of evolution from magmatic to hydrothermal stages and low-temperature subsolidus re-equilibration assemblage. The primary-late magmatic assemblage is characterized by albite, orthoclase, unaltered nepheline, zoned diopside-hedenbergite, rinkite, late magmatic eudialyte and magnesio-arfvedsonite formed at ∼700°C with maximum aSiO2 of 0.60. In contrast, a deuteric assemblage (400-348°C) is represented by aegirine-jadeite-rich clinopyroxene, post-magmatic eudialyte, sodalite, analcime and the decomposition assemblages formed after eudialyte with decreasing aSiO2 (0.52-0.48). A further low-temperature subsolidus assemblage (≤250°C) represented by late-forming natrolite could be either related to regressive stages of metamorphism or a continuum of the subsolidus processes. Considering the P/T range of the greenschist - lower-amphibolite facies of metamorphism it is evident that the incorporation of a jadeite component within pyroxene is related to a subsolidus process between ∼400°C and 348°C in a silica deficient environment. We emphasize that the deuteric fluid itself acted as an agent of metamorphism and the decomposition assemblage formed after eudialyte is retained even after metamorphism due to the convergence of subsolidus and metamorphic domains. The formation of jadeite-rich aegirine is not considered to result from metamorphism. Overall it is near-impossible to discern any bona fide metamorphic textures or mineral assemblages in these syenites which appear to preserve a relict mineralogy regardless of their occurrence in country rocks which have experienced greenschist - amphibolite facies metamorphism. The Sushina complex is very similar in this respect to the Norra Kärr complex (Sweden).
A comprehensive study based on U–Pb and Hf isotope analyses of zircons from gneisses has been conducted along the western part (Babina area) of the E–W-trending Bundelkhand Tectonic Zone in the central part of the Archaean Bundelkhand Craton. 207Pb–206Pb zircon ages and Hf isotopic data indicate the existence of a felsic crust at ~ 3.59 Ga, followed by a second tectonothermal event at ~ 3.44 Ga, leading to calc-alkaline magmatism and subsequent crustal growth. The study hence suggests that crust formation in the Bundelkhand Craton occurred in a similar time-frame to that recorded from the Singhbhum and Bastar cratons of the North Indian Shield.
Over a 2-year period, 25 families comprising of 181 individuals of all ages were longitudinally observed for the excretion of Campylobacter species. Faecal samples were taken from all persons with diarrhoea. Specimens were also taken from apparently healthy individuals and from domestic animals living within the confines of the study families at monthly intervals.
The overall diarrhoea attack rate was 19 episodes per 100 person-years with peak incidence in the 1- to 4-year-old age group (76/100 person-years). Eight (11·5%) of the total episodes were campylobacter-associated and the overall rate of campylobacter positive diarrhoeal episodes were 2·2 per 100 person-years. Of the 1002 stool samples from healthy individuals 32 (3·2/100 samples) were positive for campylobacter. The organism was most frequently isolated from children under 1 year of age both during diarrhoeal episodes (11·5 per 100 person-years) and non-diarrhoeal (11·1 per 100 samples). Multiple infections in a family were rare. In 19·4% of the occasions one or more animals were campylobacter positive. However, only in 7·7% of these occasions was a human infection recorded within 1 month after the animal was found to be positive.
The study showed that the epidemiology of campylobacteriosis in this community was distinct compared to that observed in developed countries.
The distribution and virulence of Vibrio cholerae serogroups other than O1 and O139 in India before, during and after the advent of O139 serogroup was investigated. A total of 68 strains belonging to 31 different ‘O’ serogroups were identified during the study period. With the exception of O53, there was no spatial or temporal clustering of any particular non-O1 non-O139 serogroup at any given place. Two of the 68 strains examined produced cholera toxin (CT) which could only be partially absorbed with anti-CT immunoglobulin G. Tissue culture assay revealed that some of the non-O1 non-O139 strains produced factors which evoked either a cell rounding or cell elongation response depending upon the medium used. This study indicates that serogroups other than O1 and O139 should also be continuously monitored.
During 19837 a clinical diagnosis of subacute sclerosing panencephalitis (SSPE) was confirmed by the detection of measles virus haemagglutination inhibiting antibody in the cerebrospinal fluid (CSF) in 81 subjects resident in Tamilnadu. The antibody titre (reciprocol of the endpoint dilution) in the CSF ranged from 2 to 32 and in the sera from 8 to 2048. The CSF: serum ratios of titres were 1:41:64 in 80 cases and 1:128 in one case. The median age at onset of SSPE was 10 years and 97% of cases were diagnosed at stage 2 and beyond. Based on the geographic distribution of 72 cases in an estimated population of 84 million, the annual incidence of SSPE was calculated to be 214 per million population, or 43 cases per million children below 20 years. Assuming that only 10% of all cases would have reached the level of laboratory diagnosis, the incidence may be as high as 21 cases per million population.
Pulsed laser deposited cerium oxide (CeO2) nanoporous thin film on platinum (Pt) coated glass has been used for immobilization of glucose oxidase (GOx) by electrostatic interaction. Atomic force microscopy studies reveal the formation of nanoporous surface morphology of CeO2 thin film. Differential pulse voltammetric and optical measurements show that the GOx/CeO2/Pt bioelectrode is sensitive to the detection of glucose over the concentration upto 300 mg/dl. A low value of enzyme's kinetic parameter (Michaelis-Menten constant∼1.01 mM) indicates enhanced enzyme affinity of GOx to glucose.
In this study the status of oxidant stress, vitamin A and angiotensin-converting enzyme (ACE) levels were evaluated in cases of laryngeal carcinoma patients from Northern India. In control subjects the levels of malondialdehyde (MDA), vitamin A and ACE were 0.23 ± 0.07 nmole/ml, 2515 ± 84 IU, and 1.4 ± 0.8 U/ml respectively. Thirty laryngeal cancer patients were divided into three groups according to the TNM classification (American Joint Committee on Cancers). In laryngeal cancer patients according to tumour size, MDA and ACE levels increased to 0.32 ± 0.04 nmole/ml and 4.7 ± 0.5 U/ml respectively and the effect was statistically significant (p<0.01). The correlation coefficient between different subgroups was also highly significant (r =0.96, p<0.01). However, serum vitamin A levels decreased to 621 ± 20 IU and the effect was statistically significant (p<0.01). In another two groups of laryngeal cancer patients, a similar pattern of various markers was obtained. Thirty patients with laryngeal carcinoma were divided into four different groups according to nodal involvement and it was observed that in laryngeal cancer patients with no nodal involvement, ACE levels were low 3.6 ± 1.4 U/ml while patients with maximum nodal involvement had the highest levels of ACE 7.1 ± 0.18 U/ml. The correlation coefficient between different groups is highly statistically significant (r = 0.95, p<0.01). In patients with laryngeal cancer the serum MDA and vitamin A levels correlation coefficient between different groups was not significant. It is thus concluded that serum ACE might be a specific test marker for laryngeal cancer disease burden. The use of this marker enzyme for therapeutics is being planned.
Thin films of BaZrO3 (BZ) were grown using a pulsed laser deposition technique on platinum coated silicon substrates. Films showed a polycrystalline perovskite structure upon different annealing procedures of in-situ and ex-situ crystallization. The composition analyses were done using Energy dispersive X-ray analysis (EDAX) and Secondary ion mass spectrometry (SIMS). The SIMS analysis revealed that the ZrO2 formation at the right interface of substrate and the film leads the degradation of the device on the electrical properties in the case of ex-situ crystallized films. But the in-situ films exhibited no interfacial formation. The dielectric properties have been studied for the different temperatures in the frequency regime of 40 Hz to 100kHz. The response of the film to external ac stimuli was studied at different temperatures, and it showed that ac conductivity values in the limiting case are correspond to oxygen vacancy motion. The electrical modulus is fitted to a stretched exponential function and the results clearly indicate the presence of the non-Debye type of dielectric relaxation in these materials.
This study traces the evolutionary pathways of the apolipoprotein B gene in the low risk Chinese
and high risk Asian Indians in relation to coronary artery disease (CAD). Haplotypes were
constructed from six apoB polymorphisms sp24/27, Ag(c/g),
Ag(a1/d), XbaI, Ag(h/i) and, Ag(t/z).
These were genotyped from 474 Chinese (253 healthy, 221 CAD patients) and 248 Asian Indians (164
healthy, 84 CAD patients). The maximum parsimony method was used to construct a cladogram for
each ethnic group. Three haplotypes in the Chinese and one in the Indians were found exclusively
in CAD patients. These haplotypes were sp27ca1X-ht,
sp24ga1X-iz and sp24ca1X+it
in Chinese, and sp24cdX-it in Indians. Those in the Chinese all occurred
as terminal haplotypes and represented the
most recent mutations. Evolutionary pathways for both ethnic groups were similar for majority of
the haplotypes except for the presence of an additional third branch in the Indians arising from the
ancestral haplotype. However, this third branch does not appear to contribute to the susceptibility
of the Indians to CAD.
An approximate analysis, based on the standard perturbation technique, is described in this paper to find the corrections, up to first order to the reflection and transmission coefficients for the scattering of water waves by a submerged slender barrier, of finite length, in deep water. Analytical expressions for these corrections for a submerged nearly vertical plate as well as for a submerged vertically symmetric slender barrier of finite length are also deduced, as special cases, and identified with the known results. It is verified, analytically, that there is no first order correction to the transmitted wave at any frequency for a submerged nearly vertical plate. Computations for the reflection and transmission coefficients up to O(ε), where ε is a small dimensionless quantity, are also performed and presented in the form of both graphs and tables.
The on-farm performance of more than 150 000 pre-basic potato (Solanum tuberosum) minitubers of 1–10 g was monitored over two years in contrasting environments in Nepal. Average minituber productivity (grams of basic seed produced per minituber planted) was 171 g in the southern plains and 116 g in the hills. Although the performance of minitubers varied between environments, minituber sizes and potato varieties, the overall results clearly indicated that minitubers can be successfully multiplied by small-scale farmers. This technology therefore allows for the highly decentralized production of basic seed which, in turn, will reduce farmers' dependence on an unreliable and costly supply of bulky conventional seed.
1. The vitamin A content of human liver tissue was determined in 363 autopsy samples. The sample comprised a total of 181 subjects dying after accidents and 182 dying from coronary heart disease among Singapore ethnic groups of both sexes.
2. The medium vitamin A reserve was 146 mg/kg in accident victims and 141 mg/kg in those who had died of coronary heart disease. Of all the samples 16% contained less than 40 mg/kg, 45% had 100–300 mg/kg, while 9% contained more than 500 mg/kg liver.
3. Among the accident victims, Indians had the lowest median liver vitamin A reserve (118 mg/kg) compared with that in other ethnic groups (137 mg/kg in Chinese, 191 mg/kg in Malays, 155 mg/kg in Caucasians).
4. The ethnic distribution of vitamin A reserve in coronary deaths was similar to that in accident victims.
5. There was no significant difference between the sexes in hepatic vitamin A reserve.
6. The distribution of vitamin A reserve in all the groups was skewed to the right.
Eleven patients with tardive dyskinesia were treated with lithium carbonate in a placebo-controlled double-blind crossover study. No significant effect of lithium on either tardive dyskinesia or blood prolactin concentrations was demonstrated, but 5 patients developed pseudo-Parkinsonian features.