1,673 research outputs found
Sr-Nd isotope geochemistry of the early Precambrian sub-alkaline mafic igneous rocks from the southern Bastar craton, Central India
Sr–Nd isotope data are reported for the early Precambrian sub-alkaline mafic igneous rocks of the southern Bastar craton, central India. These mafic rocks are mostly dykes but there are a few volcanic exposures. Field relationships together with the petrological and geochemical characteristics of these mafic dykes divide them into two groups; Meso-Neoarchaean sub-alkaline mafic dykes (BD1) and Paleoproterozoic (1.88 Ga) sub-alkaline mafic dykes (BD2). The mafic volcanics are Neoarchaean in age and have very close geochemical relationships with the BD1 type. The two groups have distinctly different concentrations of high-field strength (HFSE) and rare earth elements (REE). The BD2 dykes have higher concentrations of HFSE and REE than the BD1 dykes and associated volcanics and both groups have very distinctive petrogenetic histories. These rocks display a limited range of initial 143Nd/144Nd but a wide range of apparent initial 87Sr/86Sr. Initial 143Nd/144Nd values in the BD1 dykes and associated volcanics vary between 0.509149 and 0.509466 and in the BD2 dykes the variation is between 0.510303 and 0.510511. All samples have positive εNd values the BD1 dykes and associated volcanics have εNd values between +0.3 and +6.5 and the BD2 dykes between +1.9 to +6.0. Trace element and Nd isotope data do not suggest severe crustal contamination during the emplacement of the studied rocks. The positive εNd values suggest their derivation from a depleted mantle source. Overlapping positive εNd values suggest that a similar mantle source tapped by variable melt fractions at different times was responsible for the genesis of BD1 (and associated volcanics) and BD2 mafic dykes. The Rb–Sr system is susceptible to alteration and resetting during post-magmatic alteration and metamorphism. Many of the samples studied have anomalous apparent initial 87Sr/86Sr suggesting post-magmatic changes of the Rb–Sr system which severely restricts the use of Rb–Sr for petrogenetic interpretation
Study of Early Predictors of Fatality in Mechanically Ventilated Neonates in NICU
Objective: To evaluate the risk factors associated with fatality in mechanically ventilated neonates using multiple regression analysis. Design & settings: Prospective study conducted at Neonatal ICU at New Civil Hospital, Surat – a tertiary care centre, from December, 2007 to May, 2008 for 6 months. Methods: Fifty neonates in NICU consecutively put on mechanical ventilator during study period were enrolled in the study. The pressure limited time cycled ventilator was used. All admitted neonates were subjected to an arterial blood gas analysis along with a set of investigations to look for pulmonary maturity, infections, renal function, hyperbilirubinemia, intraventricular hemorrhage and congenital anomalies. Different investigation facilities were used as and when required during ventilation of neonates. Multiple logistic regression analysis was done to find out the predictors of fatality among these neonates. Results: Various factors suspected as predictors of fatality of mechanically ventilated neonates were assessed. Hypothermia, prolonged capillary refill time (CRT), initial requirement of oxygen fraction (FiO2) >0.6, alveolar to arterial PO2 difference (AaDO2) >250, alveolar to arterial PO2 ratio (a/A) <0.25, & oxygenation index (OI) >10 were found statistically highly significant predictors of mortality among mechanically ventilated neonates. Conclusion: Hypothermia and prolonged capillary refill time were independent predictors of fatality in neonatal mechanical ventilation. Risk of fatality can be identified in mechanically ventilated neonates
Measurement of particulate pollution in Jabalpur city during Diwali festival
The ambient air quality monitoring network involves measurement of number of air pollutant. A variety of method exist to measure particular matter in air
Study of risk factors causing coronary heart disease among army personnel of the rank non-commissioned officers and below in the age group of 20-50 years and its association with prehypertension
Background: Coronary heart disease (CHD) is an acute public health problem both in developed and in developing countries, like India. Assessing the prevalence of CHD in the community is equivalent to assessing the tip of the iceberg. Hypertension is a major risk factor for CHD and hypertension disease prevalence tip of the iceberg in the community is much more obscure.
Objective: The objective of the study was to carry out a cross-sectional study among serving Army personnel, comprising healthy non-commissioned officers and other rank personnel to successfully assess the risk factors for CHD and their association with prehypertension.
Materials and Methods: Screening of risk factors for CHD among 200 randomly selected participants was carried out. Blood pressure, height, weight, serum total cholesterol, serum triglycerides, serum high-density lipoprotein (HDL), random blood sugar levels, and smoking status were the major risk factors screened.
Results: Nearly 63% of Army personnel were found to be having blood pressure commensurate to the range of prehypertension. About 15% were detected to be overweight, 22% had hypercholesterolemia, 5.4% had impaired glucose tolerance (IGT), and 19.2% were current smokers. Higher age, body mass index, high serum triglycerides, low serum HDL, and IGT were found to be independently associated with increased prevalence of prehypertension in multiple logistic regression analysis.
Conclusion: Our findings recommend the constant monitoring of CHD risk factors and the formulation of effective preventive strategies for adequate control of alarming incidence
Fusion of axis with third cervical vertebra: A case report
Introduction: Fusion of one or more contiguous vertebral segments is usually the result of embryological failure of normal spinal segmentation. It may be associated with syndromes such as Klippel-Feil. Fused cervical vertebrae (FCV) may also be acquired or pathologic. FCV is generally associated with disease like tuberculosis, other infections, juvenile rheumatoid arthritis and trauma. The commonest site of involvement is C2-C3. In condition of fusion the two vertebrae appear not only structurally as one but also function as one. This anomaly may be asymptomatic; however, it may also manifest in the form of serious clinical features such as myelopathy, limitation of the neck movement, muscular weakness, atrophy or neurological sensory loss.Case report: We observed the fusion of axis with 3rd cervical vertebra. Body, laminae and spines of C2 and C3 were completely fused on both anterior and posterior aspects, whereas the pedicles and transverse processes were not fused. Foramen transversarium was present on both the vertebrae bilaterally.Conclusion: This variation is noteworthy to neurosurgeons and radiologists in studying computed tomography (CT) and magnetic resonance imaging (MRI) scans
Small inhibitor of Bcl-2, HA14-1, selectively enhanced the apoptotic effect of cisplatin by modulating Bcl-2 family members in MDA-MB-231 breast cancer cells
Inhibition or downregulation of Bcl-2 represents a new therapeutic approach to by-pass chemoresistance in cancer cells. Therefore, we explored the potential of this approach in breast cancer cells. Cisplatin and paclitaxel induced apoptosis in a dose-dependent manner in MCF-7 (drug-sensitive) and MDA-MB-231 (drug-insensitive) cells. Furthermore, when we transiently silenced Bcl-2, both cisplatin and paclitaxel induced apoptosis more than parental cells. Dose dependent induction of apoptosis by drugs was enhanced by the pre-treatment of these cells with HA14-1, a Bcl-2 inhibitor. Although the effect of cisplatin was significant on both cell lines, the effect of paclitaxel was much less potent only in MDA-MB-231 cells. To further understand the distinct role of drugs in MDA-MB-231 cells pretreated with HA14-1, caspases and Bcl-2 family proteins were studied. The apoptotic effect of cisplatin with or without HA14-1 pre-treatment is shown to be caspase-dependent. Among pro-apoptotic Bcl-2 proteins, Bax and Puma were found to be up-regulated whereas Bcl-2 and Bcl-x(L) were down-regulated when cells were pretreated with HA14-1 followed by paclitaxel or cisplatin. Enforced Bcl-2 expression in MDA-MB-231 cells abrogated the sensitizing effect of HA14-1 in cisplatin induced apoptosis. These results suggest that the potentiating effect of HA14-1 is drug and cell type specific and may not only depend on the inhibition of Bcl-2. Importantly, alteration of other pro-apoptotic or anti-apoptotic Bcl-2 family members may dictate the apoptotic response when HA14-1 is combined with chemotherapeutic drugs
Challenges and opportunities associated with waste management in India
India faces major environmental challenges associated with waste generation and inadequate waste collection, transport, treatment and disposal. Current systems in India cannot cope with the volumes of waste generated by an increasing urban population, and this impacts on the environment and public health. The challenges and barriers are significant, but so are the opportunities. This paper reports on an international seminar on ‘Sustainable solid waste management for cities: opportunities in South Asian Association for Regional Cooperation (SAARC) countries’ organized by the Council of Scientific and Industrial Research-National Environmental Engineering Research Institute and the Royal Society. A priority is to move from reliance on waste dumps that offer no environmental protection, to waste management systems that retain useful resources within the economy. Waste segregation at source and use of specialized waste processing facilities to separate recyclable materials has a key role. Disposal of residual waste after extraction of material resources needs engineered landfill sites and/or investment in waste-to-energy facilities. The potential for energy generation from landfill via methane extraction or thermal treatment is a major opportunity, but a key barrier is the shortage of qualified engineers and environmental professionals with the experience to deliver improved waste management systems in India
Ant-based Neural Topology Search (ANTS) for Optimizing Recurrent Networks
Hand-crafting effective and efficient structures for recurrent neural networks (RNNs) is a difficult, expensive, and time-consuming process. To address this challenge, we propose a novel neuro-evolution algorithm based on ant colony optimization (ACO), called Ant-based Neural Topology Search (ANTS), for directly optimizing RNN topologies. The procedure selects from multiple modern recurrent cell types such as ∆-RNN, GRU, LSTM, MGU and UGRNN cells, as well as recurrent connections which may span multiple layers and/or steps of time. In order to introduce an inductive bias that encourages the formation of sparser synaptic connectivity patterns, we investigate several variations of the core algorithm. We do so primarily by formulating different functions that drive the underlying pheromone simulation process (which mimic L1 and L2 regularization in standard machine learning) as well as by introducing ant agents with specialized roles (inspired by how real ant colonies operate), i.e., explorer ants that construct the initial feed forward structure and social ants which select nodes from the feed forward connections to subsequently craft recurrent memory structures. We also incorporate communal intelligence, where best weights are shared by the ant colony for weight initialization, reducing the number of backpropagation epochs required to locally train candidate RNNs, speeding up the neuro-evolution process. Our results demonstrate that the sparser RNNs evolved by ANTS significantly outperform traditional one and two layer architectures consisting of modern memory cells, as well as the well-known NEAT algorithm. Furthermore, we improve upon prior state-of-the-art results on the time series dataset utilized in our experiments
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