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131.
A current model for carotenoid transport and absorption in the gut proposes an initial solubilization in the oil phase of dietary emulsions followed by incorporation of the carotenoids in mixed bile salt micelles. To assess the relevance of the first stage of this model to what is observed in vivo we have examined the transfer of carotene from carrot juice to olive oil. Increased acidity enhanced the transfer from both whole juice and carotene crystals isolated from both whole juice and carotene crystals isolated from carrot chromoplasts. The transfer was significantly slower from whole juice. By using exogenous β-carotene and measuring its transfer to oil in the presence and absence of carrot juice we have demonstrated that the inhibition of the transfer in juice arises, at least in part, from soluble juice factors. The inhibition is relieved by a fall in pH, which leads to lowering of the electric potential at the oil/aqueous phase interface and aggregation of carrot tissue including crystalline carotene. Under conditions of low pH, oil droplets adhere to the tissue aggregates, allowing carotene to pass into the oil. Our results provide an explanation for why carotene absorption in vivo is depressed by conditions of low gastric acidity. 相似文献
132.
Ramzi A.A. Mothana Sidgi S. Hasson Wulf Schultze Annette Mowitz Ulrike Lindequist 《Food chemistry》2011
The chemical composition of three essential oils obtained from the barks of three endemic Boswellia species namely, Boswellia dioscorides, Boswellia elongata and Boswellia socotrana which were collected from the Soqotra Island (Yemen), was investigated. In parallel to that evaluation of their antimicrobial and antioxidant activities was also carried out. The investigation led to the identification of 72, 70 and 67 constituents for B.dioscorides, B. elongata, and B. socotrana, respectively. The B. dioscorides oil was found to have a high content of monoterpene hydrocarbons (32.8%) with α-thujene (9.3%) and α-pinene (8.3%) as main components. Whereas, the essential oil of B. elongata was characterised by high diterpene content (31.7%), in which incensol (14.8%) was found to be the major constituent. On the other hand, the oil obtained from the B. socotrana was found to be predominated of monoterpene hydrocarbons (26.4%) and oxygenated monoterpenes (30.7%) with p-cymene (13.0%), 2-hydroxy-5-methoxy-acetophenone (16.3%) and camphor (11.6%). All essential oils possessed antimicrobial activity especially against Gram-positive bacteria with MIC-values between 1.8 and 17.2 mg/ml. Furthermore, the DPPH-radical scavenging assay exhibited only weak antioxidant activities (28%) at 1.0 mg/ml. 相似文献
133.
In the testing of ocean wave energy devices, the demand for a portable and robust data acquisition and electrical loading system has become apparent. This paper investigates the development of a 30 kW inclusive system combining loading capabilities, real-time power analysis, and data acquisition for the testing of deployed ocean wave energy devices. Hardware results for ocean testing are included. 相似文献
134.
Annette Evans Vladimir Strezov Tim J. Evans 《Renewable & Sustainable Energy Reviews》2012,16(6):4141-4147
Renewable energy technologies are expected to take the leading role in the forthcoming energy generation portfolio in order to achieve sustainable energy generation. The major constraints for increasing penetration of renewable energy sources is their availability and intermittency, which can be addressed through energy storage when available and energy use when needed. This work reviews the energy storage technologies and gives an up to date comparative summary of the performance parameters of the major energy storage options. The parameters compared here include efficiency, energy capacity, energy density, run time, capital investment costs, response time, lifetime in years and cycles, self discharge and maturity of each energy storage option. The choice of storage system will depend on individual requirements, and may even incorporate more than one energy storage system to increase the energy storage capacity and improve energy security. 相似文献
135.
Dr. Dimitra T. Pournara Anna Durner Dr. Eftichia Kritsi Alexios Papakostas Dr. Panagiotis Zoumpoulakis Prof. Dr. Annette Nicke Dr. Maria Koufaki 《ChemMedChem》2020,15(24):2530-2543
The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide ( 56 ) exhibiting the best potency with an IC50 value of 0.39 μM. 相似文献
136.
Annette Abraham Ajoe John Kattoor Tom Saldeen 《Critical reviews in food science and nutrition》2019,59(17):2831-2838
AbstractVitamin E is a lipid soluble vitamin comprising of eight natural isoforms, namely, α, β, δ, γ isoforms of tocopherol and α, β, δ, γ isoforms of tocotrienol. Many studies have been performed to elucidate its role in cancer. Until last decade, major focus was on alpha tocopherol and its anticancer effects. However, major clinical trials using alpha-tocopherol like SELECT trial and ATBC trial did not yield meaningful results. Hence there was a shift of focus to gamma-tocopherol, delta-tocopherol and tocotrienol. Unlike alpha-tocopherol, gamma-tocopherol and delta-tocopherol can scavenge reactive nitrogen species in addition to reactive oxygen species. Antiangiogenic effect, inhibition of HMG CoA reductase enzyme and inhibition of NF-κB pathway make the anti-cancer effects of tocotrienols unique compared to other vitamin E isoforms. Preclinical research on non-alpha tocopherol isoforms of vitamin E showed promising data on their anticancer effects. In this review, we deal with the current understanding on the potential mechanisms involved in the anticancer effects of vitamin E and the controversies in this field over last three decades. We also highlight the need to conduct further research on the anticancer effects of non-alpha-tocopherol isoforms in larger population and clinical setting. 相似文献
137.
Annette L. West Louise V. Michaelson Elizabeth A. Miles Richard P. Haslam Karen A. Lillycrop Ramona Georgescu Lihua Han Johnathan A. Napier Philip C. Calder Graham C. Burdge 《Lipids》2021,56(2):229-242
The phospholipid composition of lipoproteins is determined by the specificity of hepatic phospholipid biosynthesis. Plasma phospholipid 20:4n-6 and 22:6n-3 concentrations are higher in women than in men. We used this sex difference in a lipidomics analysis of the impact of endocrine factors on the phospholipid class and molecular species composition of fasting plasma from young men and women. Diester species predominated in all lipid classes measured. 20/54 Phosphatidylcholine (PtdCho) species were alkyl ester, 15/48 phosphatidylethanolamine (PtdEtn) species were alkyl ester, and 12/48 PtdEtn species were alkenyl ester. There were no significant differences between sexes in the proportions of alkyl PtdCho species. The proportion of alkyl ester PtdEtn species was greater in women than men, while the proportion of alkenyl ester PtdEtn species was greater in men than women. None of the phosphatidylinositol (PtdIns) or phosphatidylserine (PtdSer) molecular species contained ether-linked fatty acids. The proportion of PtdCho16:0_22:6, and the proportions of PtdEtn O-16:0_20:4 and PtdEtn O-18:2_20:4 were greater in women than men. There were no sex differences in PtdIns and PtdSer molecular species compositions. These findings show that plasma phospholipids can be modified by sex. Such differences in lipoprotein phospholipid composition could contribute to sexual dimorphism in patterns of health and disease. 相似文献
138.
139.
ABSTRACTCan social sustainability be built? What are the challenges and potential for incorporating the concept of social sustainability into the assessment of building projects? Theoretical approaches to social sustainability are examined for the ways it is applied in practice by building industry stakeholders. A fundamental question is whether and how social sustainability can be measured, assessed and certified in the construction or renewal of housing and neighbourhoods. In addition to physical and functional indicators, it is suggested that certification systems (e.g. the Deutsche Gesellschaft für Nachhaltiges Bauen – DGNB) should also reward social initiatives. A framework was developed involving 12 indicators grouped three overarching themes: social cohesion; participatory processes; and accessibility to living opportunities. A collaborative case study project involving two Danish social housing neighbourhoods examines how social sustainability indicators could be integrated into the application of certification systems such as the DGNB and whether the certification system can be improved by integrating social and organizational aspects with the existing criteria for physical and functional layout. It is found that certifications must take the housing complex or neighbourhood's relationship with the surrounding city into account, as well as its development over time and flexibility towards future needs. 相似文献
140.
Schuerger James M.; Zarrella Karen L.; Hotz Annette S. 《Canadian Metallurgical Quarterly》1989,56(5):777
Analyzed test–retest reliability data gathered from 106 sources (89 independent samples), using a multiple-regression method in an attempt to estimate the effects of several factors on questionnaire stability. We examined 8 self-report inventories: the High School Personality Questionnaire, the 16PF, the MMPI, the Myers–Briggs Type Indicator, the CPI, the Guilford–Zimmerman Temperament Survey, the EPPS, and the OPI. Samples ranged in size and encompassed a wide range of Ss divergent on status and age. We found S's age and status, number of test items, test interitem correlation, and test–retest interval to be significant predictors of reliability. Variables representing general adjustment were found to be less predictable than extraversion variables, and short-term reliability was more predictable than long-term reliability. S's sex and specific questionnaires were not found to have a significant effect on reliability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献