1,093 research outputs found
Projected Changes in Semi Permanent Systems of Indian Summer Monsoon in CORDEX-SA Framework
The semi-permanent systems such as Seasonal Heat Low (HL), Monsoon Trough (MT), Tibetan Anticyclone (TA), Tropical Easterly Jet (TEJ) and Low Level Jet (LLJ) or Somali jet are observed over Indian region during Indian summer monsoon season (June through September). These systems play a vital role in defining the strength of the Indian summer monsoon rainfall as a whole. Here we evaluate the ability of Consortium for Small-Scale Modeling (COSMO) regional Climate Model (COSMO-CLM), a high resolution regional climate model within the Coordinated Regional Climate Downscaling Experiment for South Asia (CORDEX-SA) framework, to simulate these systems of Indian summer monsoon. The historical runs of the COSMO-CLM for the period 1951-2000 are analysed. Overall the COSMO-CLM is able to simulate these components reasonably well. Possible changes in the position and the strength of these systems and their role in changing rainfall pattern over India are examined to assess the impact of global warming, under the RCP 4.5 simulations towards the end of the century (2051-2100). The analysis shows that the semi permanent systems may not strengthen in the future as compared to the present climate. The summer monsoon rainfall does not show uniform changes over the region. It is likely to enhance over the southern parts of the country, south of 20?S while it is projected to decrease in the northern parts under the global warming scenario
Assessing Hydrological Response to Changing Climate in the Krishna Basin of India
Impact of climate change on water balance components in the Krishna river basin are investigated using a semidistributed
hydrological model namely Soil and Water Assessment Tool (SWAT). The model is calibrated and validated
using the measured stream flow and meteorological data for the period (1970-1990) at a single guage outlet. The model
has been used further for hydrologic parameter simulations. Daily climate simulations from regional climate model
PRECIS (Providing Regional Climates for Impacts Studies) is used as input for running SWAT and monthly hydrologic
parameters such as precipitation, surface flow, water yield, Evapotranspiration (ET) and Potential Evapotranspiration
(PET) are generated under the assumption of no change in Land Use and Land Cover (LULC) pattern over time.
Simulations at 23 sub-basins of the Krishna basin have been obtained for the control runs (1961-1990) and the for
two time slices of future scenarios (2011-2040) and (2041-2070). Model projections indicate increase in the annual
discharge, surface runoff and base flow in the basin in mid-century
Projected changes in climate over the Indus river basin using a high resolution regional climate model (PRECIS)
A regional climate modelling system, the Providing REgional Climates for Impacts Studies developed by the Hadley Centre for Climate Prediction and Research, has been used to study future climate change scenarios over Indus basin for the impact assessment. In this paper we have examined the three Quantifying Uncertainty in Model Predictions simulations selected from 17-member perturbed physics ensemble generated using Hadley Centre Coupled Module. The climate projections based on IPCC SRES A1B scenario are analysed over three time slices, near future (2011-2040), middle of the twenty first century (2041-2070), and distant future (2071-2098). The baseline simulation (1961-1990) was evaluated with observed data for seasonal and spatial patterns and biases. The model was able to resolve features on finer spatial scales and depict seasonal variations reasonably well, although there were quantitative biases. The model simulations suggest a non-uniform change in precipitation overall, with an increase in precipitation over the upper Indus basin and decrease over the lower Indus basin, and little change in the border area between the upper and lower Indus basins. A decrease in winter precipitation is projected, particularly over the southern part of the basin. Projections indicate greater warming in the upper than the lower Indus, and greater warming in winter than in the other seasons. The simulations suggest an overall increase in the number of rainy days over the basin, but a decrease in the number of rainy days accompanied by an increase in rainfall intensity in the border area between the upper and lower basins, where the rainfall amount is highest
Simulated projections for summer monsoon climate over India by a high-resolution regional climate model (PRECIS)
Impact of global warming on the Indian monsoon climate is examined using Hadley Centre's highresolution regional climate model, PRECIS (Providing REgional Climates for Impact Studies). Three simulations from a 17-member Perturbed Physics Ensemble generated using Hadley Center Coupled Model (HadCM3) for the Quantifying Uncertainty in Model Predictions (QUMP) project, are used to drive PRECIS. The PRECIS simulations corresponding to the IPCCSRES A1B emission scenario are carried out for a continuous period of 1961-2098. The model shows reasonable skill in simulating the monsoon climate over India. The climate projections are examined over three time slices, viz. short (2020s, i.e. 2011-2040), medium (2050s, i.e. 2041-2070) and long (2080s, i.e. 2071-2098). The model projections indicate significant warming over India towards the end of the 21st century. The summer monsoon precipitation over India is expected to be 9-16 more in 2080s compared to the baseline (1970s, i.e. 1961-1990) under global warming conditions. Also, the rainy days are projected to be less frequent and more intense over central India
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Comparison of outcomes of Less Invasive Surfactant Administration (LISA) in prematurely born infants in the delivery suite (DS) and the neonatal unit (NNU).
OBJECTIVE: To compare outcomes of infants who received less invasive surfactant administration (LISA) in the delivery suite (LISA-DS) to those who received LISA on the neonatal unit (LISA-NNU). STUDY DESIGN: A prospective cohort study was undertaken of all infants who received LISA in a single centre. Clinical outcomes included admission temperature, the need for intubation, durations of invasive and non-invasive ventilation, length of hospital stay (LOS) and the incidences of bronchopulmonary dysplasia (BPD), intraventricular haemorrhage (IVH), retinopathy of prematurity (ROP) and requirement for home oxygen were compared between the two groups as were complications of the procedure. RESULTS: The 54 LISA-DS infants had similar gestational ages and birth weights to the 26 LISA-NNU infants (p=0.732, p=0.928 respectively). There were no significant differences between the admission temperatures (median (range) 36.8 (36-38.7) versus 36.8 (36.4-37.7) 0C p=0.451) or need for intubation in less than 72 hours of birth (28% versus 23%, p=0.656). The durations of invasive ventilation (median 2 (0-65) days versus 1 (0-35) days p=0.188) and non-invasive ventilation (median 37 (24-81) days versus 37 (3-225) days p=0.188) and the incidences of BPD (p=0.818), IVH (p=0.106), ROP (p=0.526) and home oxygen requirement (p 0.764) were similar. The percentage of successful first attempts with LISA (63% versus 70%, p=0.816) or associated with hypoxia episodes (32% versus 42%, p=0.194) did not differ significantly by site of administration. CONCLUSION: The outcomes of LISA performed on the delivery suite were similar to those of LISA performed on the neonatal unit
Augmenting the 6-3-5 method with design information
This paper describes a comparative study between the 6-3-5 Method and the ICR Grid. The ICR Grid is an evolved variant of 6-3-5 intended to better integrate information into the concept generation process. Unlike a conventional 6-3-5 process where participants continually sketch concepts, using the ICR Grid (the name derived from its Inform, Create, Reflect activities and structured, grid-like output) participants are additionally required to undertake information search tasks, use specific information items for concept development, and reflect on the merit of concepts as the session progresses. The results indicate that although the quantity of concepts was lower, the use of information had a positive effect in a number of areas, principally the quality and variety of output. Although grounded in the area of product development, this research is applicable to any organisation undertaking idea generation and problem solving. As well as providing insights on the transference of information to concepts, it holds additional interest for studies on the composition and use of digital libraries
A comparison of transgenic rodent mutation and in vivo comet assay responses for 91 chemicals.
A database of 91 chemicals with published data from both transgenic rodent mutation (TGR) and rodent comet assays has been compiled. The objective was to compare the sensitivity of the two assays for detecting genotoxicity. Critical aspects of study design and results were tabulated for each dataset. There were fewer datasets from rats than mice, particularly for the TGR assay, and therefore, results from both species were combined for further analysis. TGR and comet responses were compared in liver and bone marrow (the most commonly studied tissues), and in stomach and colon evaluated either separately or in combination with other GI tract segments. Overall positive, negative, or equivocal test results were assessed for each chemical across the tissues examined in the TGR and comet assays using two approaches: 1) overall calls based on weight of evidence (WoE) and expert judgement, and 2) curation of the data based on a priori acceptability criteria prior to deriving final tissue specific calls. Since the database contains a high prevalence of positive results, overall agreement between the assays was determined using statistics adjusted for prevalence (using AC1 and PABAK). These coefficients showed fair or moderate to good agreement for liver and the GI tract (predominantly stomach and colon data) using WoE, reduced agreement for stomach and colon evaluated separately using data curation, and poor or no agreement for bone marrow using both the WoE and data curation approaches. Confidence in these results is higher for liver than for the other tissues, for which there were less data. Our analysis finds that comet and TGR generally identify the same compounds (mainly potent mutagens) as genotoxic in liver, stomach and colon, but not in bone marrow. However, the current database content precluded drawing assay concordance conclusions for weak mutagens and non-DNA reactive chemicals
Decolorization of synthetic melanoidins-containing wastewater by a bacterial consortium
The presence of melanoidins in molasses wastewater leads to water pollution both due to its dark brown color and its COD contents. In this study, a bacterial consortium isolated from waterfall sediment was tested for its decolorization. The identification of culturable bacteria by 16S rDNA based approach showed that the consortium composed of Klebsiella oxytoca, Serratia mercescens, Citrobacter sp. and unknown bacterium. In the context of academic study, prevention on the difficulties of providing effluent as well as its variations in compositions, several synthetic media prepared with respect to color and COD contents based on analysis of molasses wastewater, i.e., Viandox sauce (13.5% v/v), caramel (30% w/v), beet molasses wastewater (41.5% v/v) and sugarcane molasses wastewater (20% v/v) were used for decolorization using consortium with color removal 9.5, 1.13, 8.02 and 17.5%, respectively, within 2 days. However, Viandox sauce was retained for further study. The effect of initial pH and Viandox concentration on decolorization and growth of bacterial consortium were further determined. The highest decolorization of 18.3% was achieved at pH 4 after 2 day of incubation. Experiments on fresh or used medium and used or fresh bacterial cells, led to conclusion that the limitation of decolorization was due to nutritional deficiency. The effect of aeration on decolorization was also carried out in 2 L laboratory-scale suspended cell bioreactor. The maximum decolorization was 19.3% with aeration at KLa = 2.5836 h-1 (0.1 vvm)
Exchange bias effect in alloys and compounds
The phenomenology of exchange bias effects observed in structurally
single-phase alloys and compounds but composed of a variety of coexisting
magnetic phases such as ferromagnetic, antiferromagnetic, ferrimagnetic,
spin-glass, cluster-glass and disordered magnetic states are reviewed. The
investigations on exchange bias effects are discussed in diverse types of
alloys and compounds where qualitative and quantitative aspects of magnetism
are focused based on macroscopic experimental tools such as magnetization and
magnetoresistance measurements. Here, we focus on improvement of fundamental
issues of the exchange bias effects rather than on their technological
importance
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