To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The study area belongs to the Singhbhum metamorphic belt of Jharkhand, situated in the eastern part of India. The spatial distribution of the index minerals in the pelitic schists of the area shows Barrovian type of metamorphism. Three isograds, viz. garnet, staurolite and sillimanite, have been delineated and the textural study of the schists has revealed a time relation between crystallization and deformation. Series of folds with shifting values of plunges in the supracrustal rocks having axial-planar schistosity to the folds have been widely cited. Development of these folds could be attributed to the second phase of deformation. In total, two phases of deformation, D1 and D2, in association with two phases of metamorphism, M1 and M2, have been lined up in the study area. Chemographic plots of reactant and product assemblages corresponding to various metamorphic reactions suggest that the pattern of metamorphic zones mapped in space is in coherence with the temporal-sequential change during prograde metamorphism. The prograde P–T evolution of the study area has been obtained using conventional geothermobarometry, internally consistent winTWQ program and Perple_X software in the MnNCKFMASHTO model system. Our observations suggest that the progressive metamorphism in the area is not related to granitic intrusion or migmatization but that it was possibly the ascending plume that resulted in the M1 phase of metamorphism followed by D1 deformation. The second and prime metamorphic phase, M2, with its possible heat source generated by crustal overloading, was preceded by D1 and it lasted until late- to post-D2 deformation.
A comprehensive study of the fundamental characteristics of leading-edge separation in rarefied hypersonic flows is undertaken and its salient features are elucidated. Separation of a boundary layer undergoing strong expansion is typical in many practical hypersonic applications such as base flows of re-entry vehicles and flows over deflected control surfaces. Boundary layer growth under such conditions is influenced by effects of rarefaction and thermal non-equilibrium, thereby differing significantly from the conventional no-slip Blasius type. A leading-edge separation configuration presents a fundamental case for studying the characteristics of such a flow separation but with minimal influence from a pre-existing boundary layer. In this work, direct simulation Monte Carlo computations have been performed to investigate flow separation and reattachment in a low-density hypersonic flow over such a configuration. Distinct features of leading-edge flow, limited boundary layer growth, separation, shear layer, flow structure in the recirculation region and reattachment are all explained in detail. The fully numerical shear layer profile after separation is compared against a semi-theoretical profile, which is obtained using the numerical separation profile as the initial condition on existing theoretical concepts of shear layer analysis based on continuum flow separation. Experimental studies have been carried out to determine the surface heat flux using thin-film gauges and computations showed good agreement with the experimental data. Flow visualisation experiments using the non-intrusive planar laser-induced fluorescence technique have been performed to image the fluorescence of nitric oxide, from which velocity and rotational temperature distributions of the separated flow region are determined.
Background: In aneurysms overall, a lower rate of recanalization in stent assisted coiling vs coiling alone has been observed without an increase in morbidity. This study aims to stratify and compare degree of occlusion outcome by treatment modalities. Secondarily, this study aims to stratify and compare postoperative adverse events. Methods: MEDLINE and EMBASE databases were searched. Study center were reviewed for inclusion. We performed meta-regressions, bias analysis and fail-safe N. We controlled for the quality of the studies. Results: 396 nonduplicated patients were separated into 4 groups: microsurgical, stent-assisted coiling, coiling, stent only. Stent-assisted coiling has lower rate of retreatment (17 vs 24%) and higher rehemorrhage (5% vs 3%) compared to coiling. Stent-assisted has higher rates of complete occlusion (55% vs 45%) and lower rate of residual aneurysm (15% vs 23%) compared to coiling. Comparative analyses were performed. Microsurgical remained the most morbid modality with the best rate of complete occlusion (93%) and lowest rehemorrhage (2%) and retreatment rate (5%). Conclusions: This is the first and largest meta-analysis focusing on patients treated for basilar apex aneurysm. To our knowledge, this is the first study to stratify and compare degree of occlusion per treatment modality. This study provides benchmark numbers to guide clinicians.
Background: Headaches are a major cause of disability and healthcare cost worldwide. When investigating headaches etiology, incidental unruptured intracranial aneurysms are often considered unrelated. We conducted a systematic review and meta-analysis to assess headaches outcomes (severity) after treatment of unruptured intracranial aneurysm. Methods: MEDLINE and EMBASE were systematically reviewed. Results: The data from eligible studies (n=7) was extracted and analyzed. 309 nonduplicated patients provided patient-level data for analysis. All studies used the 10-point numeric rating scale (NRS). 88% of patients were treated with endovascular technique. Overall, the observed effect estimate under a random effects model was found to be a standard mean difference in pre- and post-intervention headache severity of -0.448 (95% CI: -0.566 to -0.329). No significant heterogeneity was noted. No significant publication bias was demonstrated. Conclusions: This is the first and largest systematic review assessing postoperative headache outcomes after treatment of unruptured intracranial aneurysm. A significant reduction in headache intensity after treatment is observed in the current published literature. This study highlights an interesting clinical phenomenon that still warrants scientific effort before it can influence clinical practice. We encourage future study to stratify headache outcomes by aneurysm size, location and treatment modality.
Monolithic integrated thin film tandem solar cells consisting of a high bandgap perovskite top cell and a low bandgap thin film bottom cell are expected to reach higher power conversion efficiencies (PCEs) with lower manufacturing cost and environmental impacts than the market-dominant crystalline silicon photovoltaics. There have been several demonstrations of 4-terminal and 2-terminal perovskite tandem devices with CuInGaSe2 (CIGS) or CuInSe2 (CIS) and, similar to the other tandem structures, the optimization of this device relies on optimal choice for the perovskite bandgap and thickness. Therefore, further advancement will be enabled by tuning the perovskite absorber to maximize the photocurrent limited by the current match condition. Here, we systematically study the optical absorption and transmission of perovskite thin films with varying absorber band gap. Based on these results, we model the photocurrent generations in both perovskite and CIS subcells and estimate the performances of projected tandem devices by considering the ideally functioning perovskite and CIS device. Our results show that for perovskite layers with 500 nm thickness the optimal bandgap is around 1.6 eV. With these configurations, PCEs above 20% could be achieved by monolithically integrated perovskite/CIS tandem solar cells. Also by modelling the absorption at every layer we calculate the quantum efficiency at each subcell in addition to tracking optical losses.
Populations of the White-rumped Vulture Gyps bengalensis, Indian Vulture G. indicus and Slender-billed Vulture G. tenuirostris declined rapidly during the mid-1990s all over their ranges in the Indian subcontinent because of poisoning due to veterinary use of the non-steroidal anti-inflammatory drug diclofenac. This paper reports results from the latest in a series of road transect surveys conducted across northern, central, western and north-eastern India since the early 1990s. Results from the seven comparable surveys now available were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level. The previously rapid decline of White-rumped Vulture has slowed and may have reversed since the ban on veterinary use of diclofenac in India in 2006. A few thousand of this species, possibly up to the low tens of thousands, remained in India in 2015. The population of Indian Vulture continued to decline, though probably at a much slower rate than in the 1990s. This remains the most numerous of the three species in India with about 12,000 individuals in 2015 and a confidence interval ranging from a few thousands to a few tens of thousands. The trend in the rarest species, Slender-billed Vulture, which probably numbers not much more than 1,000 individuals in India, cannot be determined reliably.
Birth weight is used as a proxy for the general health condition of newborns. Low birth weight leads to adverse events and its effects on child growth are both short- and long-term. Low birth weight babies are more common in twin gestations. The aim of this study was to assess the effects of maternal and socio-demographic risk factors at various quantiles of the birth weight distribution for twin gestations using quantile regression, a robust semi-parametric technique. Birth records of multiple pregnancies from between 1991 and 2005 were identified retrospectively from the birth registry of the Christian Medical College and hospitals in Vellore, India. A total of 1304 twin pregnancies were included in the analysis. Demographic and clinical characteristics of the mothers were analysed. The mean gestational age of the twins was 36 weeks with 51% having preterm labour. As expected, the examined risk factors showed different effects at different parts of the birth weight distribution. Gestational age, chroniocity, gravida and child’s sex had significant effects in all quantiles. Interestingly, mother’s age had no significant effect at any part of the birth weight distribution, but both maternal and paternal education had huge impacts in the lower quantiles (10th and 25th), which were underestimated by the ordinary least squares (OLS) estimates. The study shows that quantile regression is a useful method for risk factor analysis and the exploration of the differential effects of covariates on an outcome, and exposes how OLS estimates underestimate and overestimate the effects of risk factors at different parts of the birth weight distribution.
Non-canonical wakes of two-dimensional elliptic cylinders are analysed numerically for their near- and far-wake characteristics. The governing equations are solved using an immersed boundary method based projection scheme. The wakes are then classified into three distinct types according to diverse flow and thermal properties. An unexpected mean temperature evolution along the centreline of the wake is observed for certain wake states. In order to explain this unusual variation, novel heat transport models are constructed based on the vortex dynamics. These models are derived by considering vorticity is acted by flow, which has shear and swirl. Mechanisms of the primary vortex street breakdown and formation of the secondary vortex street are also proposed based on these models. A new phenomenon namely ‘dual near-wall instantaneous recirculation’ is observed, and its appearance is found to be a function of length of the primary von Kármán vortex street. The same phenomenon is also found to be responsible for the secondary peak in the Nusselt number variation along the circumference of the cylinder. Despite varied differences between the wake types, it is observed that the transitions occur through a supercritical Hopf bifurcation in all of them, at least in the von Kármán region of the wake. Low-frequency unsteadiness observed in the far wakes is examined through a signal decomposition method. Our results show that the secondary low frequency is resulting from the transition region which has a negative instability slope. Finally, onset of the primary vortex street breakdown and its scale in terms of Reynolds number is computed.
Global patterns of copy number variations (CNVs) in chromosomes are required to understand the dynamics of genome organization and complexity. For this study, analysis was performed using the Affymetrix Genome-Wide Human SNP Array 6.0 chip and CytoScan High-Density arrays. We identified a total of 44 109 CNVs from 1715 genomes with a mean of 25 CNVs in an individual, which established the first drafts of population-specific CNV maps providing a rationale for prioritizing chromosomal regions. About 19 905 ancient CNVs were identified across all chromosomes and populations at varying frequencies. CNV count, and sometimes CNV size, contributed to the bulk CNV size of the chromosome. Population specific lengthening and shortening of chromosomal length was observed. Sex bias for CNV presence was largely dependent on ethnicity. Lower CNV inheritance rate was observed for India, compared to YRI and CEU. A total of 33 candidate CNV hotspots from 5382 copy number (CN) variable region (CNVR) clusters were identified. Population specific CNV distribution patterns in p and q arms disturbed the assumption that CNV counts in the p arm are less common compared to long arms, and the CNV occurrence and distribution in chromosomes is length independent. This study unraveled the force of independent evolutionary dynamics on genome organization and complexity across chromosomes and populations.
The main objectives were to assess the adequacy of the micronutrient intakes of lactating women in a peri-urban area in Nepal and to describe the relationships between micronutrient intake adequacy, dietary diversity and sociodemographic variables.
A cross-sectional survey was performed during 2008–2009. We used 24 h dietary recall to assess dietary intake on three non-consecutive days and calculated the probability of adequacy (PA) of the usual intake of eleven micronutrients and the overall mean probability of adequacy (MPA). A mean dietary diversity score (MDDS) was calculated of eight food groups averaged over 3 d. Multiple linear regression was used to identify the determinants of the MPA.
Bhaktapur municipality, Nepal.
Lactating women (n 500), 17–44 years old, randomly selected.
The mean usual energy intake was 8464 (sd 1305) kJ/d (2023 (sd 312) kcal/d), while the percentage of energy from protein, fat and carbohydrates was 11 %, 13 % and 76 %, respectively. The mean usual micronutrient intakes were below the estimated average requirements for all micronutrients, with the exception of vitamin C and Zn. The MPA across eleven micronutrients was 0·19 (sd 0·16). The diet was found to be monotonous (MDDS was 3·9 (sd 1·0)) and rice contributed to about 60 % of the energy intake. The multiple regression analyses showed that MPA was positively associated with energy intake, dietary diversity, women’s educational level and socio-economic status, and was higher in the winter.
The low micronutrient intakes are probably explained by low dietary diversity and a low intake of micronutrient-rich foods.
One of the most successful method in quantifying the structures in the Cosmic Web is the Minkowski Functionals. In 3D, there are four minkowski Functionals: Area, Volume, Integrated Mean Curvature and the Integrated Gaussian Curvature. For defining the Minkowski Functionals one should define a surface. We have developed a method based on Marching cube 33 algorithm to generate a surface from a discrete data sets. Next we calculate the Minkowski Functionals and Shapefinder from the triangulated polyhedral surface. Applying this methodology to different data sets , we obtain interesting results related to geometry, morphology and topology of the large scale structure
The main objective of the present study was to examine the association between dietary Fe intake and dietary predictors of Fe status and Hb concentration among lactating women in Bhaktapur, Nepal. We included 500 randomly selected lactating women in a cross-sectional survey. Dietary information was obtained through three interactive 24 h recall interviews including personal recipes. Concentrations of Hb and plasma ferritin and soluble transferrin receptors were measured. The daily median Fe intake from food was 17·5 mg, and 70 % of the women were found to be at the risk of inadequate dietary Fe intake. Approximately 90 % of the women had taken Fe supplements in pregnancy. The prevalence of anaemia was 20 % (Hb levels < 123 g/l) and that of Fe deficiency was 5 % (plasma ferritin levels < 15 μg/l). In multiple regression analyses, there was a weak positive association between dietary Fe intake and body Fe (β 0·03, 95 % CI 0·014, 0·045). Among the women with children aged < 6 months, but not those with older infants, intake of Fe supplements in pregnancy for at least 6 months was positively associated with body Fe (P for interaction < 0·01). Due to a relatively high dietary intake of non-haem Fe combined with low bioavailability, a high proportion of the women in the present study were at the risk of inadequate intake of Fe. The low prevalence of anaemia and Fe deficiency may be explained by the majority of the women consuming Fe supplements in pregnancy.
We describe appropriate wafer cleaning procedure and surface passivation characteristics of various passivants used for making measurement of minority carrier lifetime (τB ) of very high quality Si wafers. These passivants include: iodine ethanol (I-E), quinhydrone methanol (QH-M), SiO2, and Al2O3. The issues related to the passivation stability and the spatial uniformity for mapping τB are also discussed.
Nanoscale metal–insulator–metal (MIM) diodes consisting of a nanoscale-thickness insulator layer sandwiched between two dissimilar metal layers offer the potential for very high frequency alternating current to direct current signal rectification. Active nanoscale tuning of electronic tunneling through the insulator layer to form point contact diodes has previously been limited to barriers composed of soft organic films due to the force limitations of conductive-atomic force microscopy. In this paper, MIM diodes with oxide-based insulators are formed in situ with sub-nanometer depth precision and characterized using a nanoindenter equipped with electrical testing capabilities. Simultaneous measurement of both electrical and nano-mechanical information is accomplished in an MIM stack of the form Nb/Nb2O5/boron-doped diamond nanoindenter tip. Using this technique, we show that the diode behavior can be electromechanically tuned over a range of more than 1 V at equivalent currents via small changes in indentation depth and the results can be modeled using a Fowler–Nordheim approximation.
The scope of computation has expanded dramatically beyond the rubric of discrete, deterministic sequential computation under which it has been studied for many decades. That focus, of course, led to a great deal of deep and beautiful theory, but our focus in this special issue of Mathematical Structures in Computer Science is on new directions that have emerged from the study of computational phenomena in other settings, and thus on a celebration of the diversity of ideas, methods, new applications and novel sources of inspiration that have marked the modern era. The papers in this issue come from sources extending far beyond the core of computer science, yet using many of the central ideas that have evolved within computer science and mathematics. The nexus of all this activity has been, on the one hand, the boundary between logic and computation, and, on the other hand, the natural sciences, particularly physics and biology. The papers in this collection are expanded versions of selected papers from the DCM 2010 workshop, which was held in Edinburgh in July 2010. The theme of the workshop was Causality, Computation and Physics.
We report a montmorillonite material with enhanced surface area but with very little alteration in cation exchange capacity (CEC) upon dealumination with para toluene sulphonic acid (p-TSA). The new material shows higher catalytic activity in comparison with mineral-acid-treated clay. Montmorillonite clay was treated with p-TSA for 10 minutes under microwave irradiation. The resulting clay was characterized by CEC, X-ray diffraction (XRD), BET analysis, Fourier transform infrared spectroscopy (FT-IR), temperature programmed desorption (TPD) of ammonia and cyclic voltametry (CV) techniques. XRD patterns show an unchanged structure of pristine matrix after the acid action. BET analysis revealed an increase in the surface area and pore volume on p-TSA treatment, indicating formation of voids in the octahedral layer which suggests dealumination. Nitrogen adsorption-desorption curves showed the creation of new micro porous regions, possibly in the octahedral sheets. In contrast to mineral acid treatment, p-TSA treated clay samples showed similar CEC which shows the absence of dissolution of isomorphously substituted Mg and Fe ions present in the octahedral layer. CV studies confirm the formation of an Al-p-TSA complex, suggesting dissolution of aluminium octahedral sheets. The complex subsequently hydrolyses, replacing interlayer cations with Al3+ ions. Similar treatment with mineral acid resulted in clay with enhanced surface area but with reduced CEC, evidently due to the removal of isomorphously substituted Fe and Mg. Further, the p-TSA treated clays showed relatively higher esterification activity under solvent-free microwave irradiation. The p-TSA treated clay retained its activity even after three subsequent runs and thus can be exploited for practical applications.
We investigated an unprecedented outbreak of fulminant hepatitis B virus (HBV) that occurred in Modasa, Gujarat (India) in 2009. Genomic analysis of all fulminant hepatic failure cases confirmed exclusive predominance of subgenotype D1. A1762T, G1764A basal core promoter (BCP) mutations, insertion of isoleucine after nt 1843, stop codon mutation G1896A, G1862T transversion plus seven other mutations in the core gene caused inhibition of HBeAg expression implicating them as circulating precore/BCP mutant virus. Two rare mutations at amino acids 89 (Ile→Ala) and 119 (Leu→Ser) in addition to other mutations in the polymerase (pol) gene may have caused some alteration in either of four pol gene domains to affect encapsidation of pregenomic RNA to enhance pathogenicity. Sequence similarity among patients' sequences suggested an involvement of a single hepatitis B mutant strain/source to corroborate the finding of gross and continued usage of HBV mutant-contaminated syringes/needles by a physician which resulted in this unprecedented outbreak of fulminant hepatitis B. The fulminant exacerbation of the disease might be attributed to mutations in the BCP/precore/core and pol genes that may have occurred due to selection pressure during rapid spread/mutation of the virus.