503 research outputs found

    Climate Change Effects on Rainfall and Management of Urban Flooding

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    Flooding in urban basins is intensifying due to increasing urbanization and climate change and variability. This thesis presents how the effects of climate change and high-intensive rainfall on the urban drainage system and management of flooding in urban areas of were studied in Mumbai, India and Southern Sweden, including Skåne and Gothenburg. Various statistical and analytical tools were applied to study trends and extreme events in two study areas. The impact of climate change on Mumbai was studied using nine GCM simulations with bias correction using DBS methodology. For Gothenburg, RCM output and observations were used to predict the characteristics of rainfall. Through use of transient DBS processed projection data, an impact analysis (climate and extreme value statistics) was performed for the future period of the years 2010 to 2099. Trend analysis using the student t-test and the Mann-Kendall test was also performed. Further, Random Cascade modelling was applied on daily rainfall data to reproduce high temporal resolution data for Mumbai. The method can be used for development of IDF curves. The generated data were used for flood modelling in the area and the generation of flood maps. Trends for monthly, seasonal, and annual precipitation were studied for Mumbai (1951-2004). For Southern Sweden, daily and multi-day precipitation trends were studied. Long-term precipitation trends were determined using the Mann-Kendall test, the student t-test, and linear regression. The trends for rainfall in Mumbai were corroborated with climatic indices using multivariate statistical tools, namely PCA and SVD. PCA was also used for explaining variability in RCM-generated precipitation in Gothenburg. Analytical analyses were made of the drainage systems in Mumbai and Gothenburg. Finally, an integrated two dimensional (2D) hydrodynamic runoff model was used to simulate storm-water flooding and related processes in the metropolitan areas of Mumbai, India. The analysis revealed a high degree of variability in rainfall over Mumbai. A significant decreasing trend for long-term southwest monsoon rainfall was found. Also, a decrease in average maximum daily rainfall was indicated. The southwest monsoon rainfall over Mumbai was found to be inversely related to the Indian Ocean dipole, the El Ninõ-Southern Oscillation, and the East Atlantic Pattern. In Southern Sweden, however, annual precipitation has increased significantly due to increasing winter precipitation. There is an increasing trend for maximum annual daily precipitation at one location where the annual maximum often occurs in winter. The number of events with short return periods is increasing, but the number of other extreme events has not increased. Evaluation of the baseline period using the DBS bias correction method showed that observed and scaled rainfall data are strongly correlated and that these can represent various key statistics including mean, variance, and extreme values. The analysis of future long-term climate projections revealed a positive significant trend for 4 out of 9 model simulations for daily extreme rainfall during the period 2010-2099. In the case of Gothenburg, the results obtained pointed towards the usefulness of high resolution RCMs for impact studies. In random cascade modelling, very good agreement between modelled and observed disaggregation rainfall series was found for time scales larger than 1/2 h when short-term data were available. Established IDF-curves showed that the current design standard for Mumbai City has a return period of less than one year. Thus, annual recurring flooding problems in Mumbai appear evident. This was further emphasized in results from flood modelling and analytical studies

    Inflation with an antisymmetric tensor field

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    We investigate the possibility of inflation with models of antisymmetric tensor field having minimal and nonminimal couplings to gravity. Although the minimal model does not support inflation, the nonminimal models, through the introduction of a nonminimal coupling to gravity, can give rise to stable de-Sitter solutions with a bound on the coupling parameters. The values of field and coupling parameters are sub-planckian. Slow roll analysis is performed and slow-roll parameters are defined which can give the required number of e-folds for sufficient inflation. Stability analysis has been performed for perturbations to antisymmetric field while keeping the metric unperturbed, and it is found that only the sub-horizon modes are free of ghost instability for de-Sitter space.Comment: 10 pages; minor correction to the claim of Sec. IV; to appear in EPJ

    Comparative Analysis of Flooding in Gothenburg, Sweden and Mumbai, India: A Review

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    To cope with flooding in cities, a combination of well working stormwater system and a resilient city is needed. As the future is uncertain, cities have to be built resilient, meaning that they can be flexible and adaptable, as it is not possible to protect the city from floods totally. Green areas in the city can provide resilience, as water can be led here e.g. during heavy rainfall. In this article the situation in Gothenburg, which is on the list of Swedish cities at risk of getting flooded, and Mumbai, where parts of the city is flooded every monsoon season, are compared. The sewage systems in Mumbai and Gothenburg were built in the same time period, late 1800’s and early 1900’s, both with British influences. The system in Mumbai has, more or less, not been developed since it was built, while the Gothenburg system has been developed along with the city expansion. Many parts of both cities were built on former marshland areas, close to the sea. Our recommendation, for both cities, is to develop the storm water systems further with sustainability and resilience perspectives in mind, including to build floodable areas close to the city centre. It is also important to educate leaders and practitioners in both cities about resilience and sustainability perspectives

    Constant-Roll Inflation in modified f(R,Ï•)f(R,\phi) gravity model using Palatini Formalism

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    In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field Ï•\phi with Ricci scalar RR in a general form of f(R,Ï•)f(R,\phi). Using Palatini approach, we write its equivalent scalar-tensor form in the Einstein frame and then apply the constant-roll condition in the equation of motion for the inflaton field. Later the tensor-to-scalar ratio and the spectral index are calculated using the slow-roll parameters and the results obtained are matched with the Planck 2018 data. We found that the results agree nicely with the observations within the parameter regime under consideration.Comment: 13 Pages and 10 Figure

    A compendium of Technologies, Practices, Services and Policies for Scaling Climate Smart Agriculture in Odisha (India)

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    Stakeholders engaged in agricultural research for development (AR4D) are increasingly tackling risks associated with climate change in smallholder systems. Accordingly, development and scaling of climate-smart agriculture (CSA) are one of the priorities for all the organizations, departments and ministries associated with the farm sector. Having a ‘one-stop-shop’ compiled in the format of a compendium for CSA technologies, practices and services would therefore serve a guide for all the stakeholders for scaling CSA in smallholder systems. Bringing out a Compendium on Climate-Smart Agriculture (CSA) for Odisha, India was therefore thought of during the workshop on ‘Scaling Climate-Smart Agriculture in Odisha’ organized at Bhubaneswar on 18-19 July 2018 by International Rice Research Institute (IRRI) in collaboration with Department of Agriculture (DoA) & Farmers’ Empowerment, Indian Council of Agricultural Research-National Rice Research Institute (ICAR-NRRI), Orissa University of Agriculture and Technology (OUAT) & International Maize and Wheat Improvement Center (CIMMYT) under the aegis of CGIAR Research program on Climate Change, Agriculture and Food Security (CCAFS). The main objectives to bring forth this compendium are: to argue the case for agriculture policies and practices that are climate-smart; to raise awareness of what can be done to make agriculture policies and practices climatesmart; and to provide practical guidance and recommendations that are well referenced and, wherever possible, based on lessons learned from practical action. CSA programmes are unlikely to be effective unless their implementation is supported by sound policies and institutions. It is therefore important to enhance institutional capacities in order to implement and replicate CSA strategies. Institutions are vital to agricultural development as well as the realisation of resilient livelihoods.They are not only a tool for farmers and decision-makers, but are also the main conduit through which CSA practices can be scaled up and sustained. The focus in this compendium is on CSA and it’s relevant aspects, i.e., (i) technologies and practices, (ii) services, (iii) technology targeting, (iv) business models, (v) capacity building, and (vi) policies. The approaches and tools available in the compendium span from face-to-face technicianfarmer dialogues to more structured exchanges of online and offline e-learning. In every scenario it is clear that tailoring to local expectations and needs is key. In particular, the voice of farmers is essential to be captured as they are the key actors to promote sustainable agriculture, and their issues need to be prioritized. CSA practices are expected to sustainably increase productivity and resilience (adaptation), reduce Greenhouse Gases (mitigation), and enhance achievement of national food security along with sustainable development goals. CSA is widely expected to contribute towards achieving these objectives and enhance climate change adaptation. CSA practices have to be included in State’s Climate Policy as a priority intervention as the state steps up efforts to tackle climate change. Furthermore, emphasis shoud be laid on CSA training for a sustainable mode to enhance CSA adoption in the state hence the relevance of developing this document. The adaption of climate related knowledge, technologies and practices to local conditions, promoting joint learning by farmers, researchers, rural advisor and widely disseminating CSA practices, is critical. This compendium brings together a collection of experiences from different stakeholders with background of agricultural extension and rural advisory services in supporting CSA. The contributions are not intended to be state-of-the art academic articles but thought and discussion pieces of work in progress. The compendium itself is a ‘living‘ document which is intended to be revised periodically

    Anisotropic Inflation in Dipolar Bose-Einstein Condensates

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    Early during the era of cosmic inflation, rotational invariance may have been broken, only later emerging as a feature of low-energy physics. This motivates ongoing searches for residual signatures of anisotropic space-time, for example in the power spectrum of the cosmic microwave background. We propose that dipolar Bose-Einstein condensates (BECs) furnish a laboratory quantum simulation platform for the anisotropy evolution of fluctuation spectra during inflation, exploiting the fact that the speed of dipolar condensate sound waves depends on direction. We construct the anisotropic analogue space-time metric governing sound, by linking the time-varying strength of dipolar and contact interactions in the BEC to the scale factors in different coordinate directions. Based on these, we calculate the dynamics of phonon power spectra during an inflation that renders the initially anisotropic universe isotropic. We find that the expansion speed provides an experimental handle to control and study the degree of final residual anisotropy. Gravity analogues using dipolar condensates can thus provide tuneable experiments for a field of cosmology that was until now confined to a single experiment, our universe.Comment: Updated Format, More References Adde

    In vitro biology of pigeon louse Colpocephalum turbinatum (Amblycera: Phthiraptera)

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    In vitro rearing of amblyceran Phthiraptera is a challenging task. A look on the literature reveals that negligible information exists on the in vitro bionomics of avian Amblycera. Present report furnishes information on the in vitro biology of an amblyceran louse, Colpocephalum turbinatum, reared at 35 ± 1?C, 75-82% Relative Humidity, at feather diet. The incubation period of the eggs of louse was determined as 5.37±0.67 days. The duration of first, second and third nymphal instars remained 5.04±0.65, 5.12±0.89 and 5.0±0.57 days, respectively. The longevity of adult female (13.04 ± 3.67 days) was comparatively longer than that of males (9.6±2.87 days). An adult female laid an average of 0.63 egg/day in vitro condition (35±1oC and 75-82% RH, at feather diet)

    Multiple myeloma: the disease and its treatment

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    Multiple myeloma represents a malignant proliferation of plasma cells derived from a single clone. The tumor, its products and the host response to it result in a number of organ dysfunctions and symptoms of bone pain, fracture, anemia, hypercalcemia, susceptibility to infection, neurologic symptoms, clotting abnormalities and manifestations of hyperviscosity. The cause of myeloma remains unexplained but it is associated with few occupations, inflammatory conditions, autoimmune illnesses, viral infections and genetic heterogeneity. Direct interaction between multiple myeloma cells and bone marrow cells activates pleiotropic signalling pathways that mediate growth, survival, migration of multiple myeloma cells and also resistance to chemotherapy. Although myeloma remains incurable, but the use of novel drugs like thalidomide, lenalidomide and bortezomib have resulted in a paradigm change in the therapy of myeloma. Their inclusion in current multiple myeloma treatment regimens have extended median overall survival especially in younger patient population. Recent advances in the molecular genetics have provided opportunities to design highly specific inhibitors of signal transduction pathways that may enhance the efficacy of standard chemotherapy drugs by reducing or altering the pathways associated with cell survival. Despite therapeutic advances, multiple myeloma ultimately relapses and remains an incurable disease. Current research goals are to further increase our knowledge, to identify additional targeted therapies, and to reduce adverse effects and improve response rate. This review focuses on recent clinical advancement in ant myeloma strategies with additional discussion dedicated to emerging drugs that may prove beneficial to patients with this disease
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