143 research outputs found

    Embedded NiTi wires for improved dynamic thermomechanical performance of silicone elastomers

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    The extraordinary properties of shape memory NiTi alloy are combined with the inherent viscoelastic behavior of a silicon elastomer. NiTi wires are incorporated in a silicon elastomer matrix. Benefits include features as electrical/thermal conductivity, reinforcement along with enhanced damping performance and flexibility. To gain more insight of this composite, a comprehensive dynamic thermomechanical analysis is performed and the temperature- as well as frequency-dependent storage modulus and the mechanical loss factor are obtained. The analyses are realized for the composite and single components. Moreover, the models to express the examined properties and their temperature along with the frequency dependencies are also presented

    Application of MootralTM Reduces Methane Production by Altering the Archaea Community in the Rumen Simulation Technique

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    The reduction of methane emissions by ruminants is a highly desirable goal to mitigate greenhouse gas emissions. Various feed additives have already been tested for their ability to decrease methane production; however, practical use is often limited due to negative effects on rumen fermentation or high costs. Organosulphur compounds from garlic (Allium sativum) and flavonoids have been identified as promising plant-derived compounds which are able to reduce methane production. Here, we evaluated the effects of a combination of garlic powder and bitter orange (Citrus aurantium) extracts, Mootral, on ruminal methane production, ruminal fermentation and the community of methanogenic Archaea by using the rumen simulation technique as ex vivo model. The experiment consisted of an equilibration period of 7 days, an experimental period of 8 days and a withdrawal period of 4 days. During the experimental period three fermenters each were either treated as controls (CON), received a low dose of Mootral (LD), a high dose of Mootral (HD), or monensin (MON) as positive control. Application of Mootral strongly reduced the proportion of methane in the fermentation gas and the production rate of methane. Moreover, the experimental mixture induced a dose-dependent increase in the production rate of short chain fatty acids and in the molar proportion of butyrate. Some effects persisted during the withdrawal period. Both, single strand conformation polymorphism and Illumina MiSeq 16S rRNA amplicon sequencing indicated an archaeal community distinct from CON and MON samples in the LD and HD samples. Among archaeal families the percentage of Methanobacteriaceae was reduced during application of both doses of Mootral. Moreover, several significant differences were observed on OTU level among treatment groups and after withdrawal of the additives for LD and HD group. At day 14, 4 OTUs were positively correlated with methane production. In conclusion this mixture of garlic and citrus compounds appears to effectively reduce methane production by alteration of the archaeal community without exhibiting negative side effects on rumen fermentation

    The redox-active drug metronidazole and thiol-depleting garlic compounds act synergistically in the protist parasite Spironucleus vortens

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    Spironucleus vortens is a protozoan parasite associated with significant mortalities in the freshwater angelfish, Pterophyllum scalare. Control of this parasite is especially problematic due to restrictions on the use of the drug of choice, metronidazole (MTZ), on fish farms. Use of garlic (Allium sativum) is undergoing a renaissance following experimental validations of its antimicrobial efficiency. Ajoene ((E,Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide), is a stable transformation product of allicin, the primary biologically active component of garlic. In the current study, an ajoene oil crude extract had a minimum inhibitory concentration (MIC) of 40 μg/ml against S. vortens. GC-MS and NMR spectroscopy revealed this ajoene extract contained a mixture of the (E) and (Z)-ajoene isomers along with diallyl disulphide (DADS) and diallyl trisulphide (DATS). The only component of the ajoene crude oil found to substantially inhibit S. vortens growth by optical density monitoring (Bioscreen C Reader) was (Z)-ajoene (MIC 16 μg/ml). Ajoene oil acted in synergy with MTZ in vitro, reducing the individual MIC of this drug (4 μg/ml) by 16-fold, and that of ajoene oil by 200-fold with a fractional inhibitory concentration (FIC) index of 0.263. This synergistic interaction was confirmed in vivo. S. vortens-infected P. scalare angelfish dosed orally with 0.5% (v/w) MTZ combined with 0.05% (v/w) ajoene displayed a significant reduction in faecal trophozoite count, whilst those fed on 0.5% MTZ flakes (half the recommended oral dose) alone did not. This study demonstrates for the first time the synergistic interaction between the synthetic drug MTZ and natural ajoene oil both in vitro and in vivo. Future work should evaluate the potential synergy of ajoene and MTZ against MTZ-resistant bacteria and protists

    Short total synthesis of ajoene

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    We describe a short total synthesis of ajoene, a major biologically active constituent of garlic. The instability of allicin as the only other known alternative starting material has led to the development of a reliable protocol for the synthesis of ajoene from simple building blocks also suitable for upscale operations

    Use of antibiotics and other treatments in Chinese adults with acute cough: an online survey

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    BACKGROUND: This study aimed to identify use of various treatments and their association with the use of antibiotics and patient reported clinical recovery in Chinese adults with acute cough. METHODS: An online survey recruiting people who had recently experienced cough was conducted. Their sociodemographic, clinical characteristics, treatments received and their perceived changes in symptoms were collected. Factors influencing avoidance of antibiotics and improvement in symptoms were explored. RESULTS: A total of 22,787 adults with recent acute cough completed the questionnaire, covering all 34 province-level administrative units in China. Most respondents were male (68.0%), young (89.4%, aged 18–45), educated to university/degree or postgraduate level (44.6%), with a median cough severity of 6/10 on a numerical rating scale. Nearly half of the participants (46.4%) reported using antibiotics, among which 93.1% were for presumed upper respiratory tract infections (URTIs). Pharmacies (48.8%) were the most common source of antibiotics. Fewer patients took antibiotics after taking CHM (14.9%), compared to those who started with home remedies (18.0%), or allopathic non-antibiotic medication (25.0%). Antibiotics, allopathic non-antibiotic medications, CHM and home remedies were all perceived beneficial in relieving cough. CONCLUSIONS: Chinese adult responders report use of a considerable variety of treatments alone or in combination for acute cough. Patient-reported clinical recovery was similar regardless of treatment. There is likely a high proportion of inappropriate use of antibiotics for treatment of simple acute cough. As the majority of respondents did not use antibiotics as a first-line, and use of CHM was associated with relief of cough symptoms and reduction in the use of antibiotics, this presents an important opportunity for prudent antibiotic stewardship in China

    From laboratory to industrial storage - Translating volatile organic compounds into markers for assessing garlic storage quality

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    Garlic (Allium sativum L.) has long been grown for its culinary and health-promoting qualities. The seasonal nature of garlic cropping requires that bulbs be stored for many months after harvest to ensure a year-round supply. During this time, quality is known to deteriorate, and efforts have been made to improve the longevity of stored bulbs. Cold temperatures within the stores prolong shelf life, but fine temperature control is needed to avoid freezing damage or cold induced stress. Here, quality traits (alliinase activity, firmness, and water content) are measured in response to a 96 h − 5 °C cold stress, to simulate the effect of non-isothermic temperature control in a − 1.5 °C warehouse. Volatile organic compounds (VOCs) are measured by thermal desorption gas chromatography time of flight mass spectrometry to identify markers of non-isothermic storage in garlic. 129 compounds were putatively identified and four (L-lactic acid, 2,6-dimethylhetpadecane, 4-methyldodecane, and methylcyclopentane) showed high predictive accuracy for cold stress. VOCs were also sampled directly from a cold storage facility and the whole profile discriminated between sampling time points. Five VOCS were highly predictive for storage time in the warehouse but were different to VOCs previously shown to discriminate between storage times in a laboratory setting. This indicates the need for realistic warehouse experiments to test quality markers

    Selective oxidation of sulfides in flow chemistry

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    A packed bed reactor with oxone has been employed for selective oxidations of sulfur compounds. Various sulfides containing different functional groups are efficiently oxidized to the corresponding sulfoxides without formation of sulfones or other side products

    World Congress Integrative Medicine & Health 2017: Part one

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