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131.
The objectives of this study were to educate consumers about value-added beef cuts and evaluate their palatability responses of a value cut and three traditional cuts. Three hundred and twenty-two individuals participated in the beef value cut education seminar series presented by trained beef industry educators. Seminar participants evaluated tenderness, juiciness, flavor, and overall like of four samples, bottom round, top sirloin, ribeye, and a value cut (Delmonico or Denver), on a 9-point scale. The ribeye and the value cut were found to be similar in all four attributes and differed from the top sirloin and bottom round. Correlations and regression analysis found that flavor was the largest influencing factor for overall like for the ribeye, value cut, and top sirloin. The value cut is comparable to the ribeye and can be a less expensive replacement. 相似文献
132.
Relva C. Buchanan Eusiuk Park Rajesh Surana Harshani Tennakone Kirthi Tennakone 《Journal of Electroceramics》2011,26(1-4):116-121
High electromechanical strains have been developed in this study in Barium Titanate ceramics, suitably doped with Nd and Zr to form a controlled concentration gradient, leading to a dome-like structure on sintering. Compacted pellets constituted of layers of barium titanate powder of varying minor amounts of Nd and Zr powders, incorporated as nitrates precursors, acquire this dome shape on sintering at 1300?C1320oC and cooling to the ambient temperature, the result of the residual thermoelastic strain. The dome structures exhibit high electromechanical responses, and the piezoelectric coefficients (deduced from electric field induced strains measurements in dome-up and dome-down positions) are also found to be exceptionally high. These Nd and Zr doped barium titanate structures could find applications as an environmentally benign material for fabrication of high displacement functionally graded electromechanical actuators in a single sintering step process. 相似文献
133.
Peter Buchanan 《Architectural Design》2015,85(2):88-93
The architecture of the Renzo Piano Building Workshop (RPBW) is renowned internationally for the formal refinement of its components and detailing as well as for its sensitive responses to context, both in terms of its physical surroundings and local construction traditions. But, as architectural author and Piano specialist Peter Buchanan reminds us, the central concern of the practice remains focused on the original core impetus of expandingthe bounds of what technology and materials can achieve. 相似文献
134.
Dougan DA; Malby RL; Gruen LC; Kortt AA; Hudson PJ 《Protein engineering, design & selection : PEDS》1998,11(1):65-74
The interactions between the Fab and single-chain Fv (scFv) fragments of an
antibody (NC10) and its antigen, influenza virus neuraminidase, were
analysed in the crystal structures of the Fab-neuraminidase and
scFv-neuraminidase complexes. To investigate the contribution to binding
made by cavities, salt links and hydrogen bonds in the antibody- antigen
interface, 14 single amino acid replacements were made at six contact
residues in the scFv fragment by site-directed mutagenesis. The binding
affinity of each mutant scFv antibody for neuraminidase was determined with
a BIAcore optical biosensor. Four of the mutations resulted in large
changes in the free energy of binding to neuraminidase (deltadeltaG > 1
kcal/mol) and together may account for approximately 70% of the free energy
of binding. Hence these data support the theory that a small number of
residues form the 'functional epitope' and are most important for binding
of NC10 to neuraminidase. The salt link between antibody residue (Asp)H56
and (Lys)N432 from neuraminidase was demonstrated to be important for
affinity, since substitution of (Asp)H56 with Asn caused a large reduction
in the free energy of binding (deltadeltaG = +2.8 kcal/mol). Hydrogen bonds
provided by (Tyr)L32 and (Asp)H56 were also important for binding: mutation
of (Tyr)L32 to Phe resulted in a significant reduction in binding affinity
(deltadeltaG = +1.7 kcal/mol). Disruption of hydrophobic interactions (van
der Waals contacts) led to significant reductions in affinity also
((Tyr)H99 to Ala, deltadeltaG = +1.5 kcal/mol; (Leu)L94 to Ala, deltadeltaG
> +3.0 kcal/mol). An attempt to increase binding affinity by filling a
cavity in the interface with a larger antibody side chain was unsuccessful,
as the free energy gained by new antibody-antigen interactions did not
compensate for the removal of cavity-bound water molecules.
相似文献
135.
Conventional and starch xanthide (SX) reinforced styrene-butadiene (SBR) rubbers from several molding compounds and a tire tread compound were compared during 90 days' storage at various controlled humidities and during 1 year's outdoor weathering. For practical compounds, where SX served as a replacement for silica or as a partial replacement for carbon black, there was little difference between conventional and corresponding SX reinforced SBR rubbers. Properly formulated SX reinforced rubbers would prove satisfactory even in demanding applications. 相似文献
136.
The microstructures of two as-cast heats of niobium-modified HP stainless steels were characterized. Particular attention
was paid to the interdendritic niobium-rich carbides formed during solidification of these alloys. At low magnifications,
these precipitates are grouped in colonies of similar lamellae. Higher magnifications revealed that the lamellae actually
obtain two distinct morphologies. The type I morphology exhibits broad planar interfaces with a smooth platelike shape. Type
II lamellae have undulating interfaces and an overall reticulated shape. To provide further insight into the origin of these
two different morphologies, the microstructure and crystallography of each have been studied in detail using high resolution
scanning electron microscopy, transmission electron microscopy, various electron diffraction methods (electron backscatter
diffraction (EBSD), selected area diffraction (SAD), and convergent beam electron diffraction (CBED)), and energy dispersive
X-ray spectroscopy. 相似文献
137.
138.
In counselling psychology, research and practice are viewed as mutually informative, and Canadian counselling psychologists conduct research in a wide range of areas, utilizing a wide range of research methods. However, there are few Canadian publications that give prominence to counselling psychology scholarly work. Over the past decade, two trends have become more prominent in the practice of counselling psychology: evidence-based practice and outcome-focused intervention. Traditionally, empirical evidence for the efficacy of practice interventions has come from randomized controlled trials. This fails to reflect the diversity of methods and practice that Canadian counselling psychologists utilize. To address this discrepancy, in this article we provide some alternate ways for obtaining empirical support for the predictive efficacy of counselling interventions. We conclude by addressing some challenges currently facing counselling psychologists in Canada (i.e., publication venues, funding for research, the connection between research and practice, preparation of students) and describing some ways for raising the profile of counselling psychology research and practice in Canada. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
139.
Microbiological criteria, food safety objectives and performance objectives, and the relationship between them are discussed and described in the context of risk-based food safety management. A modified method to quantify the sensitivity of attributes sampling plans is presented to show how sampling plans can be designed to assess a microbiological criterion. Examples presented show that testing of processed foods for confirmation of safety is often not a practical option, because too many samples would need to be analysed. Nonetheless, in such cases the classical “ICMSF cases” and sampling schemes still offer a risk-based approach for examining food lots for regulatory or trade purposes. 相似文献
140.
Since the initial report in 1978 of galactopoietic effects of a photoperiod of 16 h of light:8 h of darkness, numerous studies have confirmed long-day stimulation of milk yield. The endocrine factor(s) responsible for increased milk yield, however, has eluded identification. Recent studies suggest that insulin-like growth factor-I (IGF-I) may mediate the galactopoietic response to long day photoperiod. Indeed, long days increase IGF-I in heifers and lactating cows; in the latter case, the response preceded an increase in milk yield. In heifers and cows, the increase in IGF-I is independent of changes in circulating growth hormone. Melatonin feeding to mimic a short-day photoperiod suppressed the increase of IGF-I in heifers induced by long days. However, melatonin feeding had no effect on milk yield in cows. Despite lack of resolution of the endocrine mechanism, dairy producers are interested in how photoperiod management can be integrated with current practices throughout the lactation cycle. There is strong evidence that milk yield responses to long days persist through an entire lactation. Also, long days can be combined with bovine somatotropin (bST) to produce additive increases in milk yield. During the dry period, long days increase the periparturient surge of prolactin. However, relative to long days, short-day treatment during the dry period produces the largest magnitude of response in milk yield during the subsequent lactation. The response to short days during the dry period may be due to a priming effect on the photoperiodic response system. In summary, IGF-I has emerged as a possible mediator of the increase of milk yield in response to long-day photoperiod. Photoperiod can be combined effectively with other management techniques such as bST. Consideration of photoperiod management during the dry period is essential to maximize responses during the subsequent lactation. 相似文献