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181.
María F. Gayol Diana O. Labuckas José Aparicio Juan C. Oberti Nelson R. Grosso Carlos A. Guzmán 《Journal of the American Oil Chemists' Society》2009,86(1):65-70
The objective of the research was to characterize the quality of damaged and undamaged jojoba seeds. The study was performed
on jojoba seeds grown in La Rioja, Argentina. Proximal composition, fatty acid composition, acid value, peroxide value, conjugated
dienes and trienes and protein electrophoresis profiles were determined in undamaged (JS) and damaged jojoba seeds (DJS).
The fat content (wax) was lower in DJS (39.11%) than in JS (50.82%). The values of acid, peroxide, conjugated dienes and trienes
were higher in DJS than in JS. No difference in fatty acid composition was observed between DJS and JS. The protein content
was not significantly different between JS and DJS. However, DJS had lower soluble protein values. In the electrophoresis
profiles, the band located at 50 kDa disappeared in DJS and the intensity of the band located at 25 kDa decreased. The deterioration
process in jojoba kernels significantly affects the chemical quality of their proteins and waxes. 相似文献
182.
AG Brooks F Borrego PE Posch A Patamawenu CJ Scorzelli M Ulbrecht EH Weiss JE Coligan 《Canadian Metallurgical Quarterly》1999,162(1):305-313
The CD94/NKG2 receptors expressed by subpopulations of NK cells and T cells have been implicated as receptors for a broad range of both classical and nonclassical HLA class I molecules. To examine the ligand specificity of CD94/NKG2 proteins, a soluble heterodimeric form of the receptor was produced and used in direct binding studies with cells expressing defined HLA class I/peptide complexes. We confirm that CD94/NKG2A specifically interacts with HLA-E and demonstrate that this interaction is dependent on the association of HLA-E with peptide. Moreover, no interaction between CD94/NKG2A and classical HLA class I molecules was observed, as assayed by direct binding of the soluble receptor or by functional assays using CD94/NKG2A+ NK cells. The role of the peptide associated with HLA-E in the interaction between HLA-E and CD94/NKG2A was also assessed. All class I leader sequence peptides tested bound to HLA-E and were recognized by CD94/NKG2A. However, amino acid variations in class I leader sequences affected the stability of HLA-E. Additionally, not all HLA-E/peptide complexes examined were recognized by CD94/NKG2A. Thus CD94/NKG2A recognition of HLA-E is controlled by peptide at two levels; first, peptide must stabilize HLA-E and promote cell surface expression, and second, the HLA-E/peptide complex must form the ligand for CD94/NKG2A. 相似文献
183.
Lloyd S. Nelson Paul W. Brooks Riccardo Bonazza Michael L. Corradini 《Metallurgical and Materials Transactions B》1999,30(6):1083-1088
We have developed a simple and inexpensive encapsulated mechanical impactor that can be operated under water. The unit reproducibly
generates upward-directed pressure transients in the water with peaks of approximately 0.13 MPa measured 100 mm above its
surface. These pulses have been used to trigger steam explosions of drops of a molten ferrosilicon alloy when they are either
just above the unit in free fall through the water or shortly after they land on its surface.
The impactor is study, reliable, safe, and environmentally neutral and resets for reuse within seconds. Compared to other
triggering techniques, the impactor does not generate light, bubbles, or strong water motion that obscure or appreciably affect
the initiation or early stages of the steam explosions. This permits good imaging and measurements at essentially all times
during the triggering and subsequent development of the explosions. 相似文献
184.
Gulski E. Burger H.P. Vaillancourt G.H. Brooks R. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2000,7(1):95-101
The partial discharge (PD) measurements on power transformers are studied with a view toward discrimination and classification of different discharge sources. For this purpose digital analysis is applied to power transformers and reactors going through acceptance testing. Furthermore, based on these measurements, PD databases have been developed to support the discharge evaluation during induced voltage tests of transformers. Using this technique, a clear distinction is possible between transformers showing different discharge behavior 相似文献
185.
186.
Diana Mitlin 《Housing Studies》2001,16(4):509-522
This paper considers recent experiences in poverty reduction within urban areas. The discussion draws out emerging lessons for the provision of affordable and inclusive housing and neighbourhood development programmes that also address the diverse needs of urban poor communities. In particular, the discussion emphasises the importance of understanding the livelihoods of the poor and the strategies that lie behind these livelihoods if external interventions are to be successful in addressing the needs of low-income urban residents. 相似文献
187.
188.
This communication reports the results of some exploratory experiments to examine the surface of coal by (i) flow microcalorimetry (FM) and (ii) vapour sorption calorimetry (VSC). Excepting differential scanning calorimetry, calorimetric methods have not been widely-exploited in coal structure research. The intent of this short communication is to demonstrate that hitherto neglected calorimetric methods are very rewarding when applied to the study of coal surfaces. 相似文献
189.
190.