797 research outputs found
High-resolution polarization imaging of the Fermi blazar 3C 279
Ever since the discovery by the Fermi mission that active galactic nuclei (AGN) produce copious
amounts of high-energy emission, its origin has remained elusive. Using high-frequency radio
interferometry (VLBI) polarization imaging, we could probe the magnetic field topology of the
compact high-energy emission regions in blazars. A case study for the blazar 3C 279 reveals
the presence of multiple g -ray emission regions. Pass 8 Fermi-Large Area Telescope (LAT) data
are used to investigate the flux variations in the GeV regime; six g -ray flares were observed in
the source during November 2013 to August 2014. We use the 43 GHz VLBI data to study
the morphological changes in the jet. Ejection of a new component (NC2) during the first three
g -ray flares suggests the VLBI core as the possible site of the high-energy emission. A delay
between the last three flares and the ejection of a new component (NC3) indicates that highenergy
emission in this case is located upstream of the 43 GHz core (closer to the black hole).Accepted manuscrip
COMPARISON OF A PATIENT-SPECIFIC COMPUTED TOMOGRAPHY ORGAN DOSE SOFTWARE WITH COMMERCIAL PHANTOM-BASED TOOLS
Computed Tomography imaging is an important diagnostic tool but carries some risk due to radiation dose used to form the image. Currently, CT scanners report a measure of radiation dose for each scan that reflects the radiation emitted by the scanner, not the radiation dose absorbed by the patient. The radiation dose absorbed by organs, known as organ dose, is a more relevant metric that is important for risk assessment and CT protocol optimization. Tools for rapid organ-dose estimation are available but are limited to using general patient models. These publicly available tools are unable to model patient-specific anatomy and positioning within the scanner. To address these limitations, the Personalized Rapid Estimator of Dose in Computed Tomography (PREDICT) dosimetry tool was recently developed. This study validated the organ doses estimated by ‘PREDICT’ with ground truth values. The patient-specific PREDICT performance was also compared to two publicly available phantom-based methods: VirtualDose and NCICT. The PREDICT tool demonstrated lower organ dose errors compared to the phantom-based methods, demonstrating the benefit of patient-specific modeling. This study also developed a method to extract the walls of cavity organs, such as the bladder and the intestines, and quantified the effect of organ wall extraction on organ dose. The study found that the exogenous material within the cavity organ can affect organ dose estimate, therefore demonstrating the importance of boundary wall extraction in dosimetry tools such as PREDICT
SUSTAINABLE LIVELIHOOD AND SUSTAINABLE DEVELOPMENT: THE EXPERIENCE OF COLLECTIVE FARMING BY KUDUMBASHREE IN KERALAM, INDIA
One of the most alarming impacts of development experienced by Third world economies in the contemporary era of globalization is the fast depletion of agricultural land. This is especially so in countries in the Third world where the rapidly increasing population and unplanned growth of economies have decreased the size of croplands to highly threatened levels. There has also been a significant shift in the meaning of land in several of these locations to being an object that can be sold and bought like any other commodity. Looking at it from a wider perspective one can vividly see that all harmful impacts – ranging from shortage of food production to global warming – of development have basically arisen from the shifts in the meaning and uses of land. The context of Keralam in South India is not an exemption from these trends, where, in fact, they have more intense connotations due to the small size of its geography and the heavy density of population – high even by the standards of developing economies. The state, once known for high levels of social development, has switched its focus towards economic development from mid 1990s. This has resulted in a real estate boom in the state where there is a huge demand for land for the purposes of erecting shopping malls, residential complexes and so on. One dangerous outcome of this was that most of the land thus sold was fertile paddy fields, which play a central role in ground water conservation as well as in sustaining its rich biodiversity. The changing equations over land and its utility have considerably contributed to the changing ecological balances within the region. The need to reinvent sustainable forms of development specific to the conditions of the state was felt acutely amidst such transformations. There was a sudden demand to reinvent the productive capacity of land, especially paddy fields, in the state by both involving more people in this area as well as by resuming farming in land that otherwise remain fallow waiting for real estate agents. Kudumbasree was an organization that commenced its operations in the State in 1998 with the intention of engaging in women empowerment and poverty alleviation programmes. Its successful career has motivated its workers, basically housewives and women from different walks, to focus on non-traditional sectors in the state. As part of this, Kudumbashree started to intervene in the agriculture sector in 2002 with the objective of ensuring sustainable livelihood to poor families by bringing back fallow land to cultivation and women to agriculture. This was the context against which the idea of collective farming was introduced by the organisation. This not only ensured a new, albeit unconventional, and sustainable source of livelihood for women in the community but also has been considerably contributing to food and nutritional security of the state. This has literally revolutionized the development concepts in the society where women empowerment and livelihood programmes were combined to reinvent the idea of sustainability
Yang-Mills Magneto-Fluid Unification
We generalize the hybrid magneto-fluid model of a charged fluid interacting
with an electromagnetic field to the dynamics of a relativistic hot fluid
interacting with a non-Abelian field. The fluid itself is endowed with a
non-Abelian charge and the consequences of this generalization are worked out.
Applications of this formalism to the Quark Gluon Plasma are suggested.Comment: 6 pages, RevTex
Seagrass Meadows and Conservation
Seagrasses are submerged monocotyleodnous flowering plants adapted to complete their life cycle below the sea surface. They harbour rich diversity of marine flora and fauna of commercial imprtance; and help prevent beach erosioan and siltation. Seagrass meadows are facing numerous challenges and threats in the present context and need urgent conservation strategies for increasing fish wealth and sea health
GC-MS analysis of bioactive compounds in methanolic extract of tubers of Pueraria tuberosa (Roxb. ex Willd.) DC. - Fabaceae
The present experiment was designed to determine the bioactive constituents from tuber extracts of Pueraria tuberosa (Roxb. ex Willd.) DC. of the family Fabaceae. The medicinal value of a plant species is dependent upon its various phytochemical constituents. The chemical compositions of the methanolic extract of tubers of P. tuberosa were investigated using Gas chromatography-Mass spectrometry and about nineteen bioactive phytochemical compounds were identified. The prevailing compounds were 2, 3-Dimethylaziridine; 2-Cyclopenten-1-one, 2-hydroxy-; 2-Hydroxy-gamma-butyrolactone; 3-Methyl-1,2-cyclopentanedione; 2,5- Dimethyl-4-hydroxy-3 (2H) – furanone; Butane 2-methyl; Oxetane; Maltol; 1, 5-Anhydro-6-deoxyhexo-2,3-diulose; 2, 3-Dihydro-2, 5-dihydroxy-6-methyl-4H-pyran-4-One; 5-Hydroxymethylfurfural, Phenol,2,6-dimethoxy; Dodecanoic Acid; Guanosine; Tetradecanoic acid; Myo-inositol; Hexadecanoic Acid; 9, 12-Octadecadienoic acid, methyl ester and Cis-vaccenic acid. This was the first report on identification of bioactive compounds from methanolic extract of tubers of P. tuberosa
Mariculture of Kappaphycus alvarezii in the coastal waters of Palk Bay: crisis due to climate change or carrying capacity?
Gradual expansion in the cultivation of carrageenan yielding red alga, Kappaphycus alvarezii in the Palk Bay from the year 1996 reached its peak in 2012. Large scale introduction of numerous rafts bearing propagules of this marine alga within the bay area registered tremendous decline in the production due to decay of thallus and poor growth since August 2013. At present more than 50% of the rafts were abandoned in the shore due to drastic reduction in yield and for want of sufficient seed material required for subsequent crop. Analysis of data on SST and nutrient profile of seawater from Palk Bay area demands need for urgent carrying capacity studies for optimum biomass production. It is advisable to restrict the number of rafts (3 x 3 m size) to 225 and seed quantity of 5.4 to 6.0 tonnes per hectare
Sustainable Livelihood and Sustainable Development: the Experience of Collective Farming by Kudumbashree in Keralam, India
One of the most alarming impacts of development experienced by Third world economies in the contemporary era of globalization is the fast depletion of agricultural land. This is especially so in countries in the Third world where the rapidly increasing population and unplanned growth of economies have decreased the size of croplands to highly threatened levels. There has also been a significant shift in the meaning of land in several of these locations to being an object that can be sold and bought like any other commodity. One dangerous outcome of this was that most of the land thus sold was fertile paddy fields, which play a central role in ground water conservation as well as in sustaining its rich biodiversity. The changing equations over land and its utility have considerably contributed to the changing ecological balances within the region. The need to reinvent sustainable forms of development specific to the conditions of the state was felt acutely amidst such transformations. There was a sudden demand to reinvent the productive capacity of land, especially paddy fields, in the state by both involving more people in this area as well as by resuming farming in land that otherwise remain fallow waiting for real estate agents. Kudumbasree was an organization that commenced its operations in the State in 1998 with the intention of engaging in women empowerment and poverty alleviation programmes. Its successful career has motivated its workers, basically housewives and women from different walks, to focus on non-traditional sectors in the state. As part of this, Kudumbashree started to intervene in the agriculture sector in 2002 with the objective of ensuring sustainable livelihood to poor families by bringing back fallow land to cultivation and women to agriculture. This was the context against which the idea of collective farming was introduced by the organisation. This not only ensured a new, albeit unconventional, and sustainable source of livelihood for women in the community but also has been considerably contributing to food and nutritional security of the state. This has literally revolutionized the development concepts in the society where women empowerment and livelihood programmes were combined to reinvent the idea of sustainability
Acceptance of birth spacing methods and it’s determinants among postnatal women in a tertiary care setting from Kerala
Background: According to VISION FP2020 healthy birth spacing is defined as delaying the first birth by two years and maintaining the birth interval of at least three years between the two children with the help of various contraceptives.Methods: This was a hospital based cross sectional study conducted among primiparous postnatal women in the department of obstetrics and gynecology SAT hospital, Trivandrum for one year duration. 134 women who had their first delivery were included in this study. A semi structured questionnaire was used to study the sociodemographic variables, reproductive history, contraceptive knowledge, attitude towards contraception and intention to use birth spacing methods by interview technique.Results: The acceptance of birth spacing methods among the study population was 56.8%. 59.1% opted to use family planning methods 6 weeks after delivery while 40.9% planned to use after 6 months. Determinants which were significantly associated with acceptance of family planning methods were education of wife (p<0.01), husbands’ education, socioeconomic status, religion and contraceptive awareness (p<0.01). 47.1% of women preferred DMPA injections, 39.1% opted for intrauterine devices. 13.8% of women opted for condom. Convenience, long term protection, and ease of use were the important reasons cited. The reasons for non-acceptance included fear of side effects, spouse not staying together, opposition from husbands, lack of awareness and religious restrictions.Conclusions: Female literacy, accessibility, cafeteria approach, and counselling contributed to acceptance. If the availability and awareness of injectable contraceptives is made at all the points of health delivery system, the acceptance of birth spacing can further be increased and unplanned pregnancies avoided
NIDS: An Efficient Network Intrusion Detection Model for Security of Big Data Using Different Machine Learning classifiers
Security of the big data is one of the important challenges which needs to be addressed by designing an efficient network intrusion model for detecting the unauthenticated intruders in the network. The model should be able to detect the validity of the packet. The detection of intrusions in network was already represented by multiple researchers using different algorithms which still needs instant addressing. Proposing a machine learning classifier algorithm for intrusion detection. The KDD intrusion dataset is used in training the machine for identifying the different intrusions of the network traffic. The machine must be trained efficiently using the different classification algorithms and the security for the data needs to be attained by identifying the invalid network packets. The experimental results demonstrate that the random forest ensemble machine learning classifier is having highest accuracy of 0.2 % when compared with the existing research results in the identification of different intrusions towards the network packets
- …