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31.
Melek?Tuter H.?Ay?e?AksoyEmail author Guldem?Ustun Sergio?Riva Francesco?Secundo Serhat?ipekler 《Journal of the American Oil Chemists' Society》2003,80(3):237-241
Selective hydrolysis of borage (Borago officinalis L.) oil was catalyzed by two lipase preparations of Nigella sativa L. seeds at 40°C in a mixture of borage oil, water, and hexane. Ammonium sulfate-precipitated lipase (Nigella PL) and lipase partially purified by DEAE-ion exchange chromatography (Nigella CPL) exhibited a negative specificity toward γ-linolenic acid (GLA). Best results were obtained in the experiments conducted
with 330 U/g oil of Nigella PL and 200 U/g oil of nigella CPL. When 330 U/g oil of Nigella PL was used, after 8 h the GLA level rose from 21.9% in the starting oil to 29.6 and 41.8% in TAG and DAG fractions of the product
mixtures, respectively (1.5-fold enrichment of GLA in the total unhydrolyzed acylglycerol fraction). At 200 U/g oil enzyme
concentration of Nigella CPL, after 77 h maximum GLA enrichment was observed in the DAG fraction. The GLA content of the DAG increased to 34.6%, corresponding
to almost 1.6-fold enrichment. The relative inability of Nigella sativa lipase(s) to hydrolyze γ-linolenoyl moieties of TAG can be used for the enrichment of this acid in the unhydrolyzed acylglycerol
fractions of GLA-containing oils. 相似文献
32.
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and wheat straw fibre composites: thermal, mechanical properties and biodegradation behaviour 总被引:3,自引:0,他引:3
M. Avella G. La Rota E. Martuscelli M. Raimo P. Sadocco G. Elegir R. Riva 《Journal of Materials Science》2000,35(4):829-836
The thermal and mechanical behaviour of a biotechnological polyester (poly(3-hydroxybutyrate-co-hydroxyvalerate) (PHBV) reinforced with wheat straw fibres has been investigated. In order to improve chemico-physical interactions between the components, the reinforcing agent has been previously submitted to a treatment with high temperature steam leading to fibres richer in cellulose and more reactive. The addition of straw fibres has been found to increase the rate of PHBV crystallisation, while it does not affect the crystallinity content. Furthermore, the comparison of the mechanical properties has shown that the composites exhibit higher Young moduli and lower values of both the stress (B) and strain (B) to break than the neat matrix of PHBV. The biodegradability in different environments by means of short and long term tests has been studied. It has been observed that the presence of straw does not affect biodegradation rate evaluated in liquid environment and in long term soil burial tests. In the composting simulation test the rate of biodegradation is reduced for composites with more than 10% of straw content. The morphology of the composites has also been investigated and correlated to the biodegradation process. 相似文献
33.
In recent years, several publications have appeared on virtual reality (VR) therapy in the treatment of anxiety disorders. However, a limited number of these studies targeted stress management and relaxation. To evaluate the efficacy of VR as a support tool in the relaxation process, this study compared its efficacy with two other media (DVD and audiotape). The goals of the experiment were to test the efficacy of each condition in increasing relaxation and reducing anxiety, and whether the sense of presence-the feeling of being inside the media content-correlated with the efficacy of the treatment. Results suggested the importance of the sense of presence as a mediating variable between the media experience and the efficacy of the protocol. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
35.
Luis Miguel Sanchez Javier Fernandez Rafael Sotomayor Soledad Escolar J. Daniel. Garcia 《New Generation Computing》2013,31(3):139-161
Nowadays, shared-memory parallel architectures have evolved and new programming frameworks have appeared that exploit these architectures: OpenMP, TBB, Cilk Plus, ArBB and OpenCL. This article focuses on the most extended of these frameworks in commercial and scientific areas. This paper shows a comparative study of these frameworks and an evaluation. The study covers several capacities, such as task deployment, scheduling techniques, or programming language abstractions. The evaluation measures three dimensions: code development complexity, performance and efficiency, measure as speedup per watt. For this evaluation, several parallel benchmarks have been implemented with each framework. These benchmarks are created to cover certain scenarios, like regular memory access or irregular computation. The conclusions show some highlights, like the fact that some frameworks (OpenMP, Cilk Plus) are better for transforming quickly a sequential code, others (TBB) have a small footprint which is ideal for small problems, and others (OpenCL) are suited for heterogeneous architectures but they require a very complex development process. The conclusions also show that the vectorization support is more critical than multitasking to achieve efficiency for those problems where this approach fits. 相似文献
36.
Pieri Luca Serino Silvia Cipresso Pietro Mancuso Valentina Riva Giuseppe Pedroli Elisa 《Virtual Reality》2022,26(2):639-648
Virtual Reality - One important feature of a neuropsychological test is its ecological validity, which defines how much patients’ test scores are linked to real-life functioning. However,... 相似文献
37.
Clinical application of colony-stimulating factors (CSFs) such as recombinant human granulocyte colony-stimulating factor (rhG-CSF) and recombinant human granulocyte macrophage colony-stimulating factor (rhGM-CSF) are advancing rapidly now that these factors are approved as indicated therapy in patients with chemotherapy-induced neutropenia, patients undergoing autologous bone marrow transplantation (BMT) and patients who develop graft failure after BMT. Novel CSFs are also being explored for potential clinical application in situations not as significantly affected by rhG-CSF or rhGM-CSF. Studies determining unique effects of novel factors, combinations of factors and combinations with peripheral blood progenitor cell fusions which may lead to future clinical applications of CSFs will be reviewed. 相似文献
38.
Ma Soledad Crdova‐Aguilar Adriana Snchez Leobardo Serrano‐Carren Enrique Galindo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(11):1101-1106
The production of γ‐decalactone by the filamentous fungus Trichoderma harzianum involves four phases (oil–water–air–mycelium) and its dispersion is crucial during fermentation. Oil and biomass (when present) dispersion, as a function of the volumetric power drawn (P/V), was characterized, in two; three‐ and four‐phase systems agitated with Rushton turbines. Trichoderma harzianum mycelium was used as the solid phase in the four‐phase system. Two stages of the fermentation were simulated: the beginning (15% oil and 1.4 kgm?3 of mycelium) and the end (2% oil and 10.6 kg m?3 of mycelium). In the two‐phase system, the use of exhausted broth achieved higher oil dispersions at low P/V values as compared with distilled water. Aeration decreased the oil dispersion for the high‐oil system, but enhanced oil dispersion for the low‐oil system. Compared with the P/V used in the actual fermentation (0.2 kW m?3), a high segregation of the system was observed for the high‐oil/low‐biomass system, due to the difficulty of mixing the thick oil–air emulsion present at the top of the tank. The system simulating the end of the fermentation reached almost complete homogeneity of oil and biomass, a phenomenon due to the high biomass/oil ratio and the biomass acting as an oil carrier. © 2001 Society of Chemical Industry 相似文献
39.
40.
P. Soledad Antonel Estela M. Andrade Fernando V. Molina 《Reactive and Functional Polymers》2009,69(3):197-205
The copolymerization of aniline (Ani) and m-chloroaniline (mClA) in variable ratios was performed by chemical oxidation in HCl medium. The resulting copolymer composition was determined by elemental analysis and XPS. The results show the incorporation of additional Cl substituents in the polymer backbone when m-chloroaniline is present in the polymerization medium with a high mClA:Ani ratio. IR and NMR characterization confirms that finding. Conductivity measurements of the copolymers in salt form were also performed. UV–vis spectra for high mClA:Ani ratios show a main band centred ca. 380 nm. PM3-ZINDO/S spectra calculations suggest that the Cl substituents stabilize spinless semiquinone structures in the polymer chain which are responsible for the 380 nm band. Photoluminescence spectra are recorded and analyzed. The addition of chlorine is attributed to the lower reaction rate in high mClA:Ani ratio. Copolymers with high mClA:Ani ratio appear as materials very different from polyaniline, thus these differences should be considered regarding possible applications. 相似文献