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81.
A. Quiroga María C. Añón María Cecilia Puppo 《Journal of the American Oil Chemists' Society》2010,87(5):507-514
This study investigated, with the aim of obtaining more flexible and hydrophobic proteins, the attachment of a low chain fatty
acid, decanoic acid, to alkaline and acid soybean proteins; and the effect on their conformational and functional properties.
The extent of esterification was high at acid pH and also increased with heating. Protein solubility decreased, mainly at
the highest temperature (60 °C). Increasing levels of fatty acid formed a complex with a slightly more soluble protein with
less surface hydrophobicity. Esterified proteins exhibited aggregation/dissociation and were stabilized by different protein
subunits belonging to 7S and 11S globulins. Denaturation of these soybean protein fractions (7S and 11S) were also detected
in these complexes. The highest level of fatty acids favored formation of a more ordered protein structure. 相似文献
82.
83.
Comparison of MCNPX-C90 and TRIPOLI-4-D for fuel depletion calculations of a Gas-cooled Fast Reactor
Ricardo Reyes-Ramírez Cecilia Martín-del-Campo Juan-Luis François Emeric Brun Eric Dumonteil Fausto Malvagi 《Annals of Nuclear Energy》2010
The Gas-cooled Fast Reactor is one of the reactor concepts selected by the Generation IV International Forum for the next generation of innovative nuclear energy systems. Several fuel design concepts are being investigated. Burnup depletion of mixed fuel of uranium and plutonium, cooled with gas in a fast neutron energy spectrum must be simulated. Various codes are being developed and/or adapted to improve the quality of the results, and also to reduce the computing time required for the simulations. 相似文献
84.
L. Ekman A.-K. Nyman H. Landin U. Magnusson K. Persson Waller 《Journal of dairy science》2018,101(1):556-571
Udder cleft dermatitis (UCD) is an inflammatory skin condition affecting the anterior parts of the udder of dairy cows. The lesions may present as mild or severe skin lesions and have been associated with mastitis and digital dermatitis. The full etiology and pathogenesis are not understood and no large-scale studies have investigated prevalence and risk factors. Therefore, the main objectives of the study were to investigate the prevalence of mild and severe UCD in Swedish dairy herds and to identify risk factors associated with such lesions. We also wanted to investigate risk factors for all cases of UCD and to determine whether UCD increases the risk for mastitis and culling. A random sample of 100 freestall dairy herds were included in the study, and each herd was visited once. Cows were registered as having no, mild, or severe UCD. Additional cow and herd data were obtained via observations, interviews, and the Swedish Official Milk Recording Scheme. The data were analyzed using logistic regression models to identify risk factors for mild and severe UCD. In total, data from 3,479 cows in 99 herds were analyzed. The prevalence of mild and severe UCD was 19 and 9%, respectively. Lesions were found in 98 of 99 herds but the within-herd prevalence of mild (0–43%) and severe (0–33%) UCD varied notably between herds. Breed (Swedish Red compared with Swedish Holstein), certain udder conformation traits, and higher parity were risk factors associated with increased risk of UCD. In addition, cows with hock lesions and cows in herds with high incidence of culling due to hoof and leg diseases had a higher risk for mild UCD. More days in milk and high milk yield were cow-related risk factors associated with severe UCD. Three housing-related factors (shorter cubicles, mattress as cubicle base, and cubicles installed before 2001 compared with 2001–2005), a high incidence of veterinary-treated clinical mastitis and culling due to udder diseases, and a low incidence of culling of first-parity cows in early lactation were herd-related risk factors associated with increased risk for severe UCD. In addition, cows in herds with a high proportion of heifers older than 17 mo that were not inseminated were associated with lower risk of all UCD. Finally, UCD was not associated with the outcomes milk somatic cell count, veterinary-treated clinical mastitis, or culling in the multivariable analyses. The etiology of UCD is most likely multifactorial, involving udder conformation traits and other cow-related risk factors as well as herd-related risk factors. The high prevalence of severe UCD lesions in Swedish dairy cows emphasizes the need for preventive measures and efficient treatments. 相似文献
85.
Denis Cavallucci François Rousselot Cecilia Zanni 《Creativity & Innovation Management》2009,18(2):71-80
Tools and methods developed during the era of quality and optimization have shown their limitations and become inappropriate in the context of the requirements of innovation. Nowadays the need to rebuild design practices in enterprises is strongly felt both in terms of human skills and methodological expertise. In part, a way to face the innovation era's difficulties has been provided through the theory of inventive problem solving. This theory represents a significant breakthrough in driving problem statement and solving in a direction that is expressed through the idea that technical systems are driven by objective laws. A second postulate concerns the notion of contradiction, but so far only few contributions have addressed the relations between laws and contradictions. This paper, through a qualitative approach, presents a solution to this limitation and proposes a possible use of laws within the choice of the appropriate conflicting pair, prior to the use of any TRIZ solving techniques. Tests to observe the impact of the proposed approach were conducted in a French engineering ‘grande école’ during three semesters with 180 engineers. The contribution of this paper is twofold. On the one hand, there is a theoretical contribution to the theory of inventive problem solving. In addition, the proposed method offers especially TRIZ practitioners new ways for problem understanding and problem formulation. 相似文献
86.
Cecilia Tortajada 《国际水》2013,38(4):490-498
Abstract Present and future improvements in efficiency of the water sector in Mexico depend on the development of a cadre of well-trained professional managers in the public and private sectors, as well as on the strengthening of the private and public sector institutions. Considerable investments are needed, but the efforts will pay back in terms of more rational policy-making and management practices. This paper analyzes several important exercises on capacity building in Mexico, which took place between 1990 and 2000. Present efforts on capacity building, achievements, and concerns are also considered in terms of the training and education needed to build a new generation of water professionals who can meet the current challenges and the needs of the coming decades. The needs of the water sector in terms of capacity building have been assessed in Mexico several times in the past. The conclusions and the results have always been the same: there is an urgent need to develop better educated managers and water professionals, both in terms of numbers and skills. Even though the needs have been identified repeatedly for over a decade, and despite continuous official rhetorics on the importance and urgency of capacity building, no long-term country-specific program on capacity building has yet been developed, let alone implemented. 相似文献
87.
Mrten O. M. Edwards Roger Persson 《Journal of the Society for Information Display》2005,13(12):1035-1037
Abstract— The electro‐optical characteristics of a pixel configuration used in electrochromic viologen‐TiO2 passive‐matrix devices are studied. The configuration has two stable color states in an intermediate voltage regime. Color switching is performed by applying voltages outside this regime. The bistability is due to electrolyte‐additive controlled electron trapping in the color‐changing viologen molecules. 相似文献
88.
C. Persson C.L. Dong L. Vayssieres T. Schmitt R. Ahuja C.L. Chang J.-H. Guo 《Microelectronics Journal》2006,37(8):686-689
The electronic structures of ZnO nanoparticles and microrod arrays are studied by O 1s X-ray absorption spectroscopy (XAS) and O Kα X-ray emission spectroscopy (XES). We show that the present LDA+USIC calculation approach is suitable to correct the LDA self-interaction error of the cation d-states. The atomic eigenstates of 3d in zinc and 2p in oxygen are energetically close, which induces strong Zn-3d-O-2p hybridization. This anomalous valence band cation-d-anion-p hybridization is affected when the localization of the Zn 3d-states is taken into account. Experimentally, the XES spectra show energy dependence in the spectral shape revealing selected excitations to the Zn 3d, 4s and 4p states, hybridized with O 2p states. Strong anisotropic effects are observed for the highly oriented ZnO rods, but not for the isotropic spherical nanoparticles. The nanostructured ZnO has primarily bulk XAS and XES properties. 相似文献
89.
90.
Standard squirrel cage induction (SCI) motors are subjected to nonsinusoidal wave-shapes when supplied from adjustable-frequency inverters. In addition to causing increased heating, these wave patterns can be destructive to the insulation. In particular, pulse-width-modulated (PWM) inverter output amplitudes and risetimes are investigated. Motor insulation capabilities are discussed. Voltage reflections are simulated for various cable lengths and risetimes and are presented graphically. Simulations confirm potential problems with long cables and short risetimes. Application precautions are also suggested 相似文献