3,584 research outputs found

    MICROWAVE-ASSISTED EXTRACTION OF BIO-ACTIVE COMPOUNDS (PHENOLICS AND ALKAMIDES) FROM ECHINACEA PURPUREA

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    Objective: Echinacea purpurea is used widely for its unspecific enhancement of the immune system. It contains multiple bioactive substances, including, phenolics (caffeic acid derivatives), flavonoids, anthocyanins and alkamides. In this currently investigation, efforts are focused on the evaluation of extraction techniques viz., conventional extraction (CE) and microwave-assisted extraction (MAE) for the regeneration of the active constituents of Echinacea purpurea. Methods: The aerial parts have been separately extracted with 80% methanol by two methods; CE and MAE. Identification of the isolated compounds was carried out by spectroscopic analysis viz., UV, TLC, 1H- NMR and MS. TLC scanner system and RP-HPLC with UV detection have been employed for the quantitative determination of caffeic acid derivatives and that of alkamides content in both extracts. Results: Chicoric and caftaric acids have been isolated and identified. The results of the TLC scanner system have revealed that the concentration is about 1.19 ± 0.02 and 1.35 ± 0.03 % (w/w) for caftaric and chicoric acid, respectively of the dry plant material extracted with CE, while the concentration is 1.81 ± 0.04 and 6.19 ± 0.26 % (w/w) for the two acids, respectively of the dry plant material extracted by MAE. The results of the HPLC have revealed that the concentration of alkamides is 0.25 and 0.33 % (w/w) of the dry plant material obtained with CE and MAE, respectively. Conclusion: Our study proved that MAE is a more effective technique compared to the CE. Extraction time was reduced, with the use of less solvent and the yield amount of the extracted active compounds was increased

    Effect of Denture Base Reinforcement Using Light Cured E- Glass Fibers on the Level of Salivary Immunoglobulin A

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    BACKGROUND: A gap still exists between in vitro and clinical studies concerning the biocompatibility of the material in the oral environment and their potential to cause immunological undesirable side effects. The uses of glass fibres to improve the mechanical properties of acrylic resin denture base polymers are well documented in vitro. AIM: The present study aimed to evaluate the effect of denture base reinforcement using light-cured E- glass fibres mesh on the level of salivary immunoglobulin A (S-IgA) in patients wearing complete dentures. MATERIAL AND METHODS: Fourteen completely edentulous patients, in need of complete dentures, participated in the study. The patients were divided into two groups (n = 7) according to the treatment protocol. In the first group, patients received conventional heat-cured acrylic resin dentures. In the second group, the mandibular dentures were reinforced using light cured resin impregnated E glass fibres mesh. In both groups, salivary samples were collected using passive drool technique. The level IgA was assessed by enzyme-linked immunosorbent assay (ELISA) technique at different time intervals. Statistical analysis was carried out using one-way ANOVA followed by Tukey`s post-hoc test and independent t-test. The significant level was set at P ≤ 0.05. RESULTS: Acrylic resin dentures and reinforced ones demonstrated an increase in the mean values of IgA level at the end of the follow-up intervals. And this increase was statistically significant (P ≤ 0.05). Although, the reinforced dentures revealed higher mean values, there was no statistically significant difference between the two groups (P > 0.05) CONCLUSIONS: Within the limitations of the present study, the following could be concluded: (1) the insertion of complete dentures induced changes in the level of IgA; and (2) denture base reinforcement using light cured resin impregnated E-glass fibres mesh had a similar effect to that of heat cured acrylic resin on the level of IgA

    Cap-Assisted Technique versus Conventional Methods for Esophageal Food Bolus Extraction: A Comparative Study

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    Background/Aims Food bolus impaction is the most common form of esophageal foreign body impaction observed in adults. Clinical guidelines recommend using the push technique or retrieval methods in such cases. The push technique can cause injuries in certain clinical situations. Notably, conventional retrieval methods are time and effort consuming. Cap-assisted endoscopic extraction of an impacted food bolus is an easy and effective technique; however, more data are needed for its validation. This study compared the capassisted extraction technique with conventional methods. Methods This prospective observational multicenter study compared the success and en bloc removal rates, total procedure time, and adverse events in both techniques.. Results The study included 303 patients who underwent food bolus extraction. The push technique was used in 87 patients (28.7%) and a retrieval procedure in 216 patients (71.3%). Cap-assisted extraction was performed in 106 patients and retrieval using conventional methods in 110 patients. The cap-assisted technique was associated with a higher rate of en bloc removal (80.2% vs. 15%, p<0.01), shorter procedure time (6.9±3.5 min vs. 15.7±4.1 min, p<0.001), and fewer adverse events (0/106 vs. 9/110, p<0.001). Conclusions Cap-assisted extraction showed no adverse events, higher efficacy, and a shorter procedure time compared with conventional retrieval procedures

    Results from the CBC3 readout ASIC for CMS 2S-modules

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    The CBC3 is the latest version of the CMS Binary Chip for readout of the outer radial region of the upgraded CMS Tracker at the High Luminosity LHC. This 254-channel, 130 nm CMOS ASIC is designed to be bump-bonded to a substrate to which sensors will be wire-bonded. It will instrument double-layer 2S-modules, containing two overlaid silicon microstrip sensors, aligned with a parallel orientation. On-chip logic identifies Level-1 trigger primitives from high transverse-momentum tracks by selecting correlated clusters in the two sensors. The CBC3 was delivered in late 2016; wafer probing and performance tests have been carried out. Several prototype modules using the CBC3 have been produced and tested in the lab and in different beams. The results show that the CBC3 satisfies CMS requirements and only small corrections are needed for the final version of the chip for production

    A novel antiproton radial diagnostic based on octupole induced ballistic loss

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    We report results from a novel diagnostic that probes the outer radial profile of trapped antiproton clouds. The diagnostic allows us to determine the profile by monitoring the time-history of antiproton losses that occur as an octupole field in the antiproton confinement region is increased. We show several examples of how this diagnostic helps us to understand the radial dynamics of antiprotons in normal and nested Penning-Malmberg traps. Better understanding of these dynamics may aid current attempts to trap antihydrogen atoms

    Compression of Antiproton Clouds for Antihydrogen Trapping

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    Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report the first detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile and its relation to that of the electron plasma

    Antihydrogen formation dynamics in a multipolar neutral anti-atom trap

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    Antihydrogen production in a neutral atom trap formed by an octupole-based magnetic field minimum is demonstrated using field-ionization of weakly bound anti-atoms. Using our unique annihilation imaging detector, we correlate antihydrogen detection by imaging and by field-ionization for the first time. We further establish how field-ionization causes radial redistribution of the antiprotons during antihydrogen formation and use this effect for the first simultaneous measurements of strongly and weakly bound antihydrogen atoms. Distinguishing between these provides critical information needed in the process of optimizing for trappable antihydrogen. These observations are of crucial importance to the ultimate goal of performing CPT tests involving antihydrogen, which likely depends upon trapping the anti-atom
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