328 research outputs found

    Dissociative electron attachment to formamide

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    Formamide (HCONH2) is the smallest molecule with a peptide bond and has recently been observed in the interstellar medium (ISM), suggesting that it may be ubiquitous in star-forming regions. There is therefore considerable interest in the mechanisms by which this molecule may form. One method is electron induced chemistry within the icy mantles on the surface of dust grains. In particular it has been recently shown that functional group dependence exists in electron attachment processes giving rise to site selective fragmentation of molecules at the C-H, O-H and N-H bonds at energies well beyond the threshold for the breaking of any of these bonds allowing novel forms of chemistry that have little or no activation barriers, such as are necessary in the ISM. In this poster we present the results of resent studies on dissociative electron attachment (DEA) to formamide DEA using an improved version of a Velocity Map Imaging (VMI) spectrometer comprised of a magnetically collimated and low energy pulsed electron gun, a Faraday cup (to measure the incident current), an effusive molecular beam, a pulsed field ion extraction, a time of flight analyzer and a two-dimensional position sensitive detector consisting of microchannel plate and a phosphor screen. The VMI spectrometer measures the kinetic energy and angular distribution of the fragment anions produced in the dissociative electron attachment process. The kinetic energy measurements provide information on the internal energies of the fragment anions and determine the dissociation limits of the parent negative ion resonant states responsible for the dissociative electron attachment process. The angular distribution measurements provide the information about the symmetry of these negative ion resonant states. We shall present the details, results and conclusions of these measurements during the conference

    Simple and non-invasive diagnostics of a broad complex tachycardia in a device patient.

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access

    Bipolar ablation for deep intra-myocardial circuits: human ex vivo development and in vivo experience.

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    To access publisher's full text version of this article click on the hyperlink at the bottom of the pageCurrent conventional ablation strategies for ventricular tachycardia (VT) aim to interrupt reentrant circuits by creating ablation lesions. However, the critical components of reentrant VT circuits may be located at deep intramural sites. We hypothesized that bipolar ablations would create deeper lesions than unipolar ablation in human hearts.Ablation was performed on nine explanted human hearts at the time of transplantation. Following explant, the hearts were perfused by using a Langendorff perfusion setup. For bipolar ablation, the endocardial catheter was connected to the generator as the active electrode and the epicardial catheter as the return electrode. Unipolar ablation was performed at 50 W with irrigation of 25 mL/min, with temperature limit of 50°C. Bipolar ablation was performed with the same settings. Subsequently, in a patient with an incessant septal VT, catheters were positioned on the septum from both the ventricles and radiofrequency was delivered with 40 W. In the explanted hearts, there were a total of nine unipolar ablations and four bipolar ablations. The lesion depth was greater with bipolar ablation, 14.8 vs. 6.1 mm (P < 0.01), but the width was not different (9.8 vs. 7.8 mm). All bipolar lesions achieved transmurality in contrast to the unipolar ablations. In the patient with a septal focus, bipolar ablation resulted in termination of VT with no inducible VTs.By using a bipolar ablation technique, we have demonstrated the creation of significantly deeper lesions without increasing the lesion width, compared with standard ablation. Further clinical trials are warranted to detail the risks of this technique

    HERBAL NANOSUSPENSION: IN VITRO CANCER STUDY AGAINST DIFFERENT CELL LINES

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    Herbal formulations marketed in India for many years providing its therapeutic benefits in health problems. Medicinal plants or their phytoconstituents are less toxic and free from side effects than synthetic drugs. However, formulation aspects of these phytoconstituents are limited due to its low solubility. Nanotechnology is a promising technique to increase the solubility of herbal drugs. This will lead to a subsequent reduction in drug dose. Nanoformulations such as nanosuspension increase the solubility of poorly soluble drugs and also have good targeting effects on different cells. The efficacy of herbal nanosuspensions evaluated using different cell lines. Here, hepatocellular carcinoma cell line (SMMC-7721), human prostate cancer cell line, human myelogenous leukemia cell line, human epithelial cell line, human breast cancer cell lines (4T1, MCF-7, and MDA-MB-453), carcinomic human alveolar basal epithelial cell line (A549), human umbilical vein endothelial cell line, human colorectal adenocarcinoma cell line (HT-29), and human epithelial carcinoma cell line (HeLa) are used in the evaluation procedures. In vitro assays help in the determination of the dose range of drugs for the activity. The present review highlights the in vitro cancer studies of herbal nanosuspensions using different cell lines

    Breeding, Feeding and Distribution of Milch Animal Holdings in India:An Analysis Based on the Data from the National Dairy Sample Survey

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    This paper is prepared against the broader background of the policy debates on the breeding, feeding and distributional consequences of dairy development in India. The data for the study is drawn from the National Dairy Sample Survey covering 186 districts spread over 14 major States in the Country. Analysis presented in the paper shows that the diffusion and adoption of crossbreeding technology is an important factor contributing to the level, pattern, and sources of milk production. There is no evidence to show that the increase in milk production and widespread adoption of crossbreeding technology resulted in the intensification of the pressure on land resources for the production of livestock feed. The production of milk is carried out largely by the weaker sections of the rural society. Since agriculture is rapidly getting mechanized, draught power requirement would not work as a constraint on the diffusion and adoption of new breeds of milch animals. Drawing on the main findings, the paper offers a number of recommendations for the consolidation and acceleration of milk production and the sustainable income generation for the rural poor

    Controlled Exposure Study of Air Pollution and T-Wave Alternans in Volunteers without Cardiovascular Disease

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    Background: Epidemiological studies have assessed T-wave alternans (TWA) as a possible mechanism of cardiac arrhythmias related to air pollution in high-risk subjects and have reported associations with increased TWA magnitude. Objective: In this controlled human exposure study, we assessed the impact of exposure to concentrated ambient particulate matter (CAP) and ozone (O:3) on T-wave alternans in resting volunteers without preexisting cardiovascular disease. Methods: Seventeen participants without preexisting cardiovascular disease were randomized to filtered air (FA), CAP (150 μg/m3), O3 (120 ppb), or combined CAP + O3 exposures for 2 hr. Continuous electrocardiograms (ECGs) were recorded at rest and T-wave alternans (TWA) was computed by modified moving average analysis with QRS alignment for the artifact-free intervals of 20 beats along the V2 and V5 leads. Exposure-induced changes in the highest TWA magnitude (TWAMax) were estimated for the first and last 5 min of each exposure (TWAMax_Early and TWAMax_Late respectively). ΔTWAMax (Late–Early) were compared among exposure groups using analysis of variance. Results: Mean ± SD values for ΔTWA:Max were –2.1 ± 0.4, –2.7 ± 1.1, –1.9 ± 1.5, and –1.2 ± 1.5 in FA, CAP, O3, and CAP + O3 exposure groups, respectively. No significant differences were observed between pollutant exposures and FA. Conclusion: In our study of 17 volunteers who had no preexisting cardiovascular disease, we did not observe significant changes in T-wave alternans after 2-hr exposures to CAP, O:3, or combined CAP + O3. This finding, however, does not preclude the possibility of pollution-related effects on TWA at elevated heart rates, such as during exercise, or the possibility of delayed responses

    FAST DISSOLVING SUBLINGUAL PATCH OF PHENOBARBITAL SODIUM: FORMULATION AND IN VITRO EVALUATION

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    Objective: To formulate and characterize. Phenobarbital sodium loaded sublingual patch using biodegradable, mucoadhesive, fast-dissolving natural polymer pullulan for immediate management of epileptic seizures. Methods: Phenobarbital sodium loaded sublingual patches were prepared by the solvent casting method and were subjected to various physicochemical evaluation parameters to find the optimized sublingual patch. The&nbsp;in vitro&nbsp;drug release study and&nbsp;kinetic model of the optimized formulation was also carried out. The stability study of the optimized Phenobarbital sodium loaded sublingual patch was also done. Results: From in vitro drug release study, it was found that Phenobarbital sodium loaded sublingual patch (S4) exhibited a maximum drug release of 96.24±1.27% at the end of 60 min compared to other formulations indicating a faster drug release from the formulation with release kinetics as Higuchi diffusion model. In fact, a notable release data was obtained between 0.5 to 8 min by all formulations, specifically S4 formulation (20.84±1.97% and 77.22±2.41% drug release at the end of 0.5 min and 8 min respectively) showed a better percentage release profile in comparison with other formulations. Such a trend is vital to deliver the drug at a faster rate to promote immediate effect for managing the fatal and complicated seizure. Considering the physicochemical property and in vitro drug release data, S4 formulation was regarded as an optimized one. The stability study also confirmed that S4 formulation is stable at refrigeration conditions. Conclusion: The formulated Phenobarbital sodium loaded sublingual patch is an effective drug delivery carrier which enables faster drug release to manage epileptic seizure
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