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Flavor and oxidative stabilities were studied by organoleptic evaluation and chemical analysis of three different samples of soybean oil: unhydrogented (I); hydrogenated with nickel catalyst (II); and hydrogenated with copper-chromium catalyst (III). Analyses for these oils were: I II III iodine Value 138 109 113 Linolenate, % 8.3 3.3 0.4 Each oil was deodorized with the addition of either citric acid alone or citric acid plus BHA and BHT antioxidants. Addition of antioxidants did not improve the flavor stabilities of the oils in accelerated storage tests but did improve the flavor stabilities of II and III in light exposure tests. All three oils that received the same additive treatment had equivalent flavor stability in both accelerated storage and light exposure tests. However, both hydrogenation and antioxidant treatment improved oxidative stability as measured by the Active Oxygen Method. There was good correlation between flavor score and the logarithm of the peroxide value determined at the time of tasting. Presented at the AOCS Meeting, New York, May 1977.  相似文献   
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This article describes the concept of a "Central Data Management" (CDM) and its implementation within the large-scale population-based medical research project "Personalized Medicine". The CDM can be summarized as a conjunction of data capturing, data integration, data storage, data refinement, and data transfer. A wide spectrum of reliable "Extract Transform Load" (ETL) software for automatic integration of data as well as "electronic Case Report Forms" (eCRFs) was developed, in order to integrate decentralized and heterogeneously captured data. Due to the high sensitivity of the captured data, high system resource availability, data privacy, data security and quality assurance are of utmost importance. A complex data model was developed and implemented using an Oracle database in high availability cluster mode in order to integrate different types of participant-related data. Intelligent data capturing and storage mechanisms are improving the quality of data. Data privacy is ensured by a multi-layered role/right system for access control and de-identification of identifying data. A well defined backup process prevents data loss. Over the period of one and a half year, the CDM has captured a wide variety of data in the magnitude of approximately 5terabytes without experiencing any critical incidents of system breakdown or loss of data. The aim of this article is to demonstrate one possible way of establishing a Central Data Management in large-scale medical and epidemiological studies.  相似文献   
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Summary Purified agaritine (N-(-L(+)-glutamyl)-p-hydroxymethylphenylhydrazine) isolated fromAgaricus bisporus,p-hydrazinobenzoic acid (its presumptive precursor) and some agaritine-degradation products were tested for mutagenic activity with theSalmonella/mammalian microsome assay (Ames test). Consistent with the literature, agaritine showed a distinct direct-acting mutagenicity with the strain TA1537 (30 revertants/gmol) and with TA97. Incubation of agaritine at alkaline pH increased the mutagenic effect. Pre-incubation of agaritine with -glutamyl transferase (GT) during 10 h at room temperature (pH 8.2) even enhanced the mutagenicity by a factor of 8 to 16 depending on the strain. In accordance with this finding, syntheticp-hydroxymethylphenylhydrazine (the presumptive product of the GT catalyzed degradation) showed also a distinct direct-acting mutagenicity, but the increase was only about 3- to 6-times compared with agaritine. The hypothetical ultimate mutagenic metabolite of agaritine, thep-hydroxymethylbenzenediazonium ion, a compound occuring naturally inA. bisporus, showed the highest mutagenic activity (with TA1537 approximately 300 to 1000 revertants/ol).
Mutagene Aktivitat von Agaritin — einem Inhaltsstoff des ZuchtchampignonsAgaricus bisporus und seiner Abbauprodukte bestimmt mit demSalmonella/Säuger-Mikrosomen Test (Ames Test)
Zusammenfassung Gereinigtes Agaritin [N-(-L(+)glutamyl)-p-hydroxymethylphenylhydrazin]; (ein im ZuchtchampignonAgaricus bisporus vorkommender Inhaltsstoff),p-Hydrazinobenzoesaure (eine hypothetische Vorstufe von Agaritin) sowie einige Abbauprodukte von Agaritin wurden mit Hilfe desSalmonella/Säuger-Mikrosomen-Tests (Ames Test) auf mutagene Aktivität untersucht. In Übereinstimmung mit Literaturdaten zeigte Agaritin eine deutliche direkt wirkende mutagene Aktivitat mitSalmonella typhimurium TA1537 (30 Revertanten/gmol) and TA97. Inkubation von Agaritin bei alkalischem pH führte zu einem pH-abhangigen Anstieg der Mutagenität. Inkubation von Agaritin mit-Glutamyltransferase (GT) während 10 h (Zimmertemperatur; pH 8.2) führte sogar zu einer 8- bis 16 fachen Zunahme der Mutagenität. Synthetischesp-Hydroxymethylphenylhydrazin (das vermutliche Produkt des durch die GT katalysierten Abbaus von Agaritin) zeigte allerdings eine nur etwa 3- bis 6 mal höhere mutagene Aktivität als Agaritin. Das hypothetische ultimate Mutagen, das Hydroxymethyldiazonium-Ion, welches auch inA. bisporus vorkommt, zeigte die höchste Mutagenität (TA1537: ca. 300 bis 1000 Revertanten/gmol).
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We examine the challenges to China's transition to a low carbon electricity system, in which renewable energy would play a significant role. China's electricity system currently lacks the flexibility in planning, operations, and pricing to respond to conflicting pressures from demand growth, rising costs, and environmental mandates in a way that simultaneously maintains reliability, decarbonizes the system, and keeps prices within acceptable bounds. Greater flexibility crucially requires the ability to more systematically and transparently manage and allocate costs. This will require re-orientating sector institutions still rooted in central planning, and strengthening independent regulation. Some of the necessary changes require fundamental political and legal reforms beyond the scope of energy policy. However, the system's flexibility can still be increased through the development of traditional planning and regulatory tools and approaches, such as an avoided cost basis for energy efficiency investments, more integrated planning to improve the coordination of generation, transmission, and demand-side investments, and a transparent ratemaking process. The judicious application of OECD electricity sector experience and skills can support these developments.  相似文献   
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China has been the world's most vibrant economy and its largest source of energy demand growth over the past two decades, accounting for more than one-quarter of net growth in global primary energy consumption from 1980 to 2005. To sustain economic growth and rising living standards, China needs effective policies that anticipate and shape the country's future energy requirements. In this paper, we examine China's national economic and energy accounts over the past decade for insights into changing energy use patterns and their relationship to economic structure. Our results indicate that incipient structural changes in the Chinese energy economy and sustained economic and energy demand growth in China will pose important, and different, challenges for policymakers.  相似文献   
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A majority of the wells for the most significant announced developments in the deepwater Gulf of Mexico will penetrate salt formations thousands of feet thick. Assuring the integrity of these wells over the field lifetime is a major drilling engineering challenge. The effect of salt on long-term well integrity is tied to the constitutive behavior of the salt, and more specifically, to its creep rate. The constitutive behavior of salt has been well studied in two previous geotechnical engineering applications. A sophisticated constitutive model for salt that considers transient and steady state creep was developed under the Waste Isolation Pilot Plant, a licensed repository for transuranic waste. Further studies of salt creep were performed for the Strategic Petroleum Reserve (SPR), a series of leached storage caverns located in salt domes along the U.S. Gulf Coast. However, only a single set of laboratory creep data exists for salt from a deepwater Gulf of Mexico diapir. To constrain the constitutive response of deepwater Gulf of Mexico salt diapirs, the mineralogic composition of salt diapirs from several regions, including Ship Shoal, Ewing Bank, Mississippi Canyon, Garden Banks, Green Canyon, and Walker Ridge, was determined by quantitative X-ray diffraction analyses of drill cuttings. Water depths for the wells ranged from 718 ft to 7590 ft, and salt sections up to nearly 11,000 ft thick were penetrated. The database provides insight into the large-scale geographic variations in salt mineralogy, as well as insight into variations along vertical (or near-vertical) transects through massive salt bodies in the deepwater Gulf of Mexico. To enable comparison with on-shore domal salts with known constitutive response, mineralogic analyses were also conducted on salt cores recovered from various on-shore SPR sites. We show that that the range in composition of the salt diapirs in the deepwater Gulf of Mexico is essentially identical to the observed range in composition of the salt domes located along the U.S. Gulf Coast (to which the deepwater salt diapirs are geologically related). In light of the observed constitutive response of the sole deepwater salt diapir tested to date, we conclude that the expected constitutive response of deepwater Gulf of Mexico salt diapirs is likely to be bracketed by the observed range in constitutive response of the well-characterized Gulf Coast domal salts. We demonstrate with an example how this knowledge can be directly applied in well casing design analyses.  相似文献   
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