691 research outputs found
Spatio-textual indexing for geographical search on the web
Many web documents refer to specific geographic localities and many
people include geographic context in queries to web search engines. Standard
web search engines treat the geographical terms in the same way as other terms.
This can result in failure to find relevant documents that refer to the place of
interest using alternative related names, such as those of included or nearby
places. This can be overcome by associating text indexing with spatial indexing
methods that exploit geo-tagging procedures to categorise documents with
respect to geographic space. We describe three methods for spatio-textual
indexing based on multiple spatially indexed text indexes, attaching spatial
indexes to the document occurrences of a text index, and merging text index
access results with results of access to a spatial index of documents. These
schemes are compared experimentally with a conventional text index search
engine, using a collection of geo-tagged web documents, and are shown to be
able to compete in speed and storage performance with pure text indexing
Shellac-Structure, Characteristics & Modification
The paper attempts to document upto date status of the structural studies of Shellac. Attempt has also been made to review the literature on modification of shellac molecules to make it more acceptable to meet the growing demand of the users
Vapor sensing with arrays of carbon black-polymer composites
Thin films of carbon black-organic polymer composites have been deposited across two metallic leads, with swelling- induced resistance changes of the films signaling the presence of vapors. To identify and classify vapors, arrays of such vapor-sensing elements have been constructed, with each element containing a different organic polymer as the insulating phase. The differing gas-solid partition coefficients for the various polymers of the sensor array produce a pattern of resistance changes that can be used to classify vapors and vapor mixtures. This type of sensor array has been shown to resolve all organic vapors that have been analyzed, and can even resolve H_2O from D_2O. Blends of poly(vinyl acetate) and poly(methyl methacrylate) have been used to produce a series of sensor that response to vapors with a change in resistance of a magnitude that is not simply a linear combination of the responses of the pure polymers. These compatible blend composite detectors provided additional analyte discrimination information relative to a reference detector array that only contained composites formed using the pure polymer phases. Vapor signatures from chemicals used in land mine explosives, including TNT, DNT, and DNB, have been detected in air in short sampling time and discriminated from each other using these sensor arrays
Comparison of effects of benidipine and amlodipine on clinical and biochemical parameters in hypertensive patients: an observational study
Background: Hypertension is a widespread public health problem and a major risk factor for cardiovascular disease. Amlodipine, a calcium channel blocker, dilates arterioles by blocking L-type calcium channels. Benidipine inhibits L, N, and T type calcium channels. We compared the efficacy of Amlodipine and benidipine on blood pressure, pulse rate, proteinuria and lipid profile in hypertensive patients.Methods: The study was an observational, prospective, open label comparison. Eligible hypertensives were given either amlodipine (5mg/d) or benidipine (4mg/d). Clinical features and laboratory parameters were recorded initially and after 3 months. Adverse events were recorded with the help of a questionnaire. Compliance was assessed by return pill count.Results: Out of 35 patients, recruited for study, 16 received amlodipine and 17 were treated with benidipine and two were lost during follow up. Both the groups were well matched in terms of age, body weight, clinical findings and laboratory values. Both the drugs significantly (P <0.05) reduced systolic (142±16 to 138±15 vs.148±16 to 134±14mmHg) and diastolic blood pressure (81±9 to 79±7). In the Amlodipine group the pulse rate after treatment tended to be higher than before (70±9 to 72±10bpm). In the Benidipine group there was decrease in pulse-rate after treatment (69±9 to 67±9). Unlike Amlodipine, Benidipine significantly (P<0.05) decreased urinary protein excretion (1.0±1.2 to 1.1±1.4 vs. 1.4±2.5 to 1.1±1.7g/g-Cr) and serum triglycerides (125±25 to 120±23 vs 130±26 to 115±21mg/dl).Conclusions: In this study, amlodipine and benidipine were found to be be equally effective anti-hypertensive in patients with stage 1 hypertension. However, there was significant reduction in proteinuria and serum triglycerides in Benidipine group as compared to Amlodipine group. Benidipine may be a better alternative to existing calcium channel blockers
The Immirzi Parameter as an Instanton Angle
The Barbero-Immirzi parameter is a one parameter quantization ambiguity
underpinning the loop approach to quantum gravity that bears tantalizing
similarities to the theta parameter of gauge theories such as Yang-Mills and
QCD. Despite the apparent semblance, the Barbero-Immirzi field has resisted a
direct topological interpretation along the same lines as the theta-parameter.
Here we offer such an interpretation. Our approach begins from the perspective
of Einstein-Cartan gravity as the symmetry broken phase of a de Sitter gauge
theory. From this angle, just as in ordinary gauge theories, a theta-term
emerges from the requirement that the vacuum is stable against quantum
mechanical tunneling. The Immirzi parameter is then identified as a combination
of Newton's constant, the cosmological constant, and the theta-parameter.Comment: 24 page
A study of histological changes of human placenta in rural population of eastern India
Background: Placenta is essential for maintenance of pregnancy and for promoting normal growth and development of fetus. It forms the morphological record of anatomical condition, intrauterine events and intrapartum events of gestation. Present study has been undertaken to record the data on the morphology and histology of placenta from mothers with hypertension and diabetes.Methods: This study showed several significant morphological and histological differences in the placenta of the mother with GDM and hypertensive placenta. The histological study of the placenta was done under microscope and number of syncytial knots, cytotrophoblastic cellular proliferation, fibrinoid necrosis, endothelial proliferation, calcified and hyalinised villous spots were noted per low power field in the diabetics and hypertensive group in comparison to control group.Results: All other parameters including area, thickness, diameter, and circumference of GDM placenta show a significant increase when compared with normal placenta. The gross anatomic features of placentae e.g infarcted areas, calcified areas and marginal insertion of the umbilical cord in the study group show significant increase in value (p>0.01) in diabetic and hypertensive groups when compared to that of the control or normal group.Conclusions: In present study we found that hypertensive placentae tend to be slightly smaller in size, weight, volume, area, thickness, diameter, circumference and feto-placental ratio than normal placentae but the parameters were found to be significantly greater than that of normal placentae in case of diabetic placentae. No significant differences were found in umbilical cord insertion. In normal pregnancy cases we found several histological findings which were increased in hypertensive and diabetic cases
Vapor sensing with arrays of carbon black-polymer composites
Thin films of carbon black-organic polymer composites have been deposited across two metallic leads, with swelling- induced resistance changes of the films signaling the presence of vapors. To identify and classify vapors, arrays of such vapor-sensing elements have been constructed, with each element containing a different organic polymer as the insulating phase. The differing gas-solid partition coefficients for the various polymers of the sensor array produce a pattern of resistance changes that can be used to classify vapors and vapor mixtures. This type of sensor array has been shown to resolve all organic vapors that have been analyzed, and can even resolve H_2O from D_2O. Blends of poly(vinyl acetate) and poly(methyl methacrylate) have been used to produce a series of sensor that response to vapors with a change in resistance of a magnitude that is not simply a linear combination of the responses of the pure polymers. These compatible blend composite detectors provided additional analyte discrimination information relative to a reference detector array that only contained composites formed using the pure polymer phases. Vapor signatures from chemicals used in land mine explosives, including TNT, DNT, and DNB, have been detected in air in short sampling time and discriminated from each other using these sensor arrays
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