226 research outputs found

    Review Study on Larvicidal and Mosquito Repellent Activity of Volatile Oils Isolated from Medicinal Plants

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    Mosquito is a vector for serious human diseases like dengue fever, hemaorrhagic dengue fever and chikungunya, .yellow fever, malaria, filaria and encephalitis among these dengue, hemaorrhagic dengue and chikungunya are highly endemic diseases in Southeast Asian and African countries, causing millions of deaths each and every year. Mosquito repellents thus play a major role in preventing man-mosquito contact and there by minimize the chance of infections and its adverse effects. The development of resistance to chemical insecticides, results rebounding vectorial capacity. Synthetic repellents are chemicals which used worldwide for protection against mosquito-borne diseases and it adversely affects the environment by contaminating water, soil and air. There is an urgent need to find alternatives to the synthetic insecticides. Plants are rich source of alternative agents for control of mosquitoes and its vectors. Extracts and isolated compounds from different plant families have been evaluated for their promising larvicidal and mosquito repellent activities. Literature has documented that essential oils and extracts have been traditionally used as effective repellents. The essential oils whose repellent activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review study. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups, and their repellent activity has been linked to the presence of monoterpenes and sesquiterpenes. The present review study focused the larvicidal potential and mosquito repellent activity of different volatile oils of medicinal plants. From an economical point of view synthetic chemical is still more frequently used as repellents than essential oils; these essential oils have the potential to provide efficient and can be used as a cheap, eco-friendly, safer for humans and the environment and also efficient alternative to the chemical larvicides

    GC-MS Study On The Potentials Of Syzygium aromaticum

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    Abstract: Cloves (Syzygium aromaticum, syn. Eugenia aromaticum or Eugenia caryophyllata) are the aromatic dried flower buds of a tree in the family Myrtaceae. Cloves are native to Indonesia and used as a spice in cuisines all over the world. Eugenol comprises 72-90% of the essential oil extracted from cloves, and is the compound most responsible for the cloves' aroma. Other important essential oil constituents of clove oil include acetyl eugenol, betacaryophyllene and vanillin; crategolic acid; tannins, gallotannic acid, methyl salicylate (painkiller); the flavonoids eugenin, kaempferol, rhamnetin, and eugenitin; triterpenoids like oleanolic acid, stigmasterol and campesterol; and several sesquiterpenes. Eugenol has pronounced antiseptic and anaesthetic properties. Of the dried buds, 15 -20 percent is essential oils, and the majority of this is eugenol. A kilogram (2.2 lbs) of dried buds yields approximately 150 ml (1/4 of pint) of eugenol. Eugenol can be toxic in relatively small quantities, as low as 5 ml

    Efficacy of once-weekly Isoniazid-Streptomycin in preventing relapse of pulmonary tuberculosis

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    Two controlled studies were undertaken to assess the efficacy of streptomycin 1 g. or 0.75 g. (by random allocation) plus isoniazid 15 mg./kg. body-weight once-weekly (the SHOW regimen) in the prevention of bacteriological relapse over a 4 year period, in patients with quiescent pulmonary tuberculosis at the end of one year of chemotherapy. In the first study which involved patients with residual cavitation at one year, bacteriological relapse requiring treatment occurred in 3 per cent of 87 patients given the SHOW regimen for 12 months as compared with 21 per cent of 94 patients on a placebo, a high proportion of the relapses in the latter occurred in the 2nd year and with sensitive organisms. In the second study on patients with no residual cavitation at one year, relapse requiring treatment occurred in 2 per cent of 98 patients given the SHOW regimen for 6 months as compared with 1 per cent of 90 patients given isoniazid approximately 4.5 mg./kg. daily for 12 months

    Mycobacteriuria in pulmonary tuberculosis patients in Madras, South India

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    Three consecutive, entire, early morning urine specimens, collected from each of 137 bacteriologically confirmed pulmonary tuberculosis patients aged more than 12 years were processed for culture of M. tuberculosis by the usual centrifugation method. Of the 411 urine specimens, 5 yielded M. tuberculo- sis. About 50 ml each from 405 of the above specimens, from 135 patients, was also processed for culture by a filtration method and M. tuberculosis was isolated from only one of them. In all, mycobacteriuria was present in 5 (3.6%) of 137 patients (95% confidence inter- val being 1.2% to 8.4%). Of these patients, 92 had no history of previous chemotherapy and 3 (3.3%) excreted tubercle bacilli in Urine (95% confidence interval being 0.6% to 9.3%)

    Radiative Phase Transitions and Casmir Effect Instabilities

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    Molecular quantum electrodynamics leads to photon frequency shifts and thus to changes in condensed matter free energies often called the Casimir effect. Strong quantum electrodynamic coupling between radiation and molecular motions can lead to an instability beyond which one or more photon oscillators undergo a displacement phase transition. The phase boundary of the transition can be located by a Casimir free energy instability.Comment: ReVTeX4 format 1 *.eps figur

    Resonance Damping in Ferromagnets and Ferroelectrics

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    The phenomenological equations of motion for the relaxation of ordered phases of magnetized and polarized crystal phases can be developed in close analogy with one another. For the case of magnetized systems, the driving magnetic field intensity toward relaxation was developed by Gilbert. For the case of polarized systems, the driving electric field intensity toward relaxation was developed by Khalatnikov. The transport times for relaxation into thermal equilibrium can be attributed to viscous sound wave damping via magnetostriction for the magnetic case and electrostriction for the polarization case.Comment: 5 pages no figures ReVTeX

    The structure of Green functions in quantum field theory with a general state

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    In quantum field theory, the Green function is usually calculated as the expectation value of the time-ordered product of fields over the vacuum. In some cases, especially in degenerate systems, expectation values over general states are required. The corresponding Green functions are essentially more complex than in the vacuum, because they cannot be written in terms of standard Feynman diagrams. Here, a method is proposed to determine the structure of these Green functions and to derive nonperturbative equations for them. The main idea is to transform the cumulants describing correlations into interaction terms.Comment: 13 pages, 6 figure

    Benchmarking and Analysis of Protein Docking Performance in Rosetta v3.2

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    RosettaDock has been increasingly used in protein docking and design strategies in order to predict the structure of protein-protein interfaces. Here we test capabilities of RosettaDock 3.2, part of the newly developed Rosetta v3.2 modeling suite, against Docking Benchmark 3.0, and compare it with RosettaDock v2.3, the latest version of the previous Rosetta software package. The benchmark contains a diverse set of 116 docking targets including 22 antibody-antigen complexes, 33 enzyme-inhibitor complexes, and 60 ‘other’ complexes. These targets were further classified by expected docking difficulty into 84 rigid-body targets, 17 medium targets, and 14 difficult targets. We carried out local docking perturbations for each target, using the unbound structures when available, in both RosettaDock v2.3 and v3.2. Overall the performances of RosettaDock v2.3 and v3.2 were similar. RosettaDock v3.2 achieved 56 docking funnels, compared to 49 in v2.3. A breakdown of docking performance by protein complex type shows that RosettaDock v3.2 achieved docking funnels for 63% of antibody-antigen targets, 62% of enzyme-inhibitor targets, and 35% of ‘other’ targets. In terms of docking difficulty, RosettaDock v3.2 achieved funnels for 58% of rigid-body targets, 30% of medium targets, and 14% of difficult targets. For targets that failed, we carry out additional analyses to identify the cause of failure, which showed that binding-induced backbone conformation changes account for a majority of failures. We also present a bootstrap statistical analysis that quantifies the reliability of the stochastic docking results. Finally, we demonstrate the additional functionality available in RosettaDock v3.2 by incorporating small-molecules and non-protein co-factors in docking of a smaller target set. This study marks the most extensive benchmarking of the RosettaDock module to date and establishes a baseline for future research in protein interface modeling and structure prediction
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