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71.
M F Miller M A Carr C B Ramsey K L Crockett L C Hoover 《Journal of animal science》2001,79(12):3062-3068
In the present study, a national consumer evaluation was conducted for beef tenderness on USDA Select strip loin steaks of known Warner-Bratzler shear (WBS) force values, ranging from tough (> 5.7 kg) to tender (< 3.0 kg), and to assess the monetary value that consumers place on tenderness by determining the average price a consumer would pay for a steak in three tenderness categories. Three supermarkets in each of five metropolitan areas (Baltimore, MD/Washington D.C.; Chicago, IL; Dallas/Fort Worth, TX; Los Angeles, CA; and Lubbock, TX) were selected to represent a wide range of income, education, and ethnicity at each city. Five trained research teams traveled to the cities to collect data during the same 10-d period. Consumers (n = 734; minimum of 15 consumers/panel, three panels/store, three stores/city, five cities) were asked to evaluate samples from each tenderness classification (tender, intermediate, or tough) for overall and tenderness acceptability, overall quality, beef flavor, juiciness, tenderness, how much they would pay for the steak ($17.14, 14.28, or 10.98/kg), if they would pay more than current market price if guaranteed tender, and to estimate the number of meals in a 2-wk period that included beef. The consumers were 52% light beef users, consuming 0 to 8 meals containing beef in 2 wk, 41% heavy beef users (greater than 12 meals/2 wk), and 6% moderate beef users (9 to 12 meals/2 wk). Consumer tenderness acceptability increased as WBS values decreased (P < 0.05). The transition in consumer perception from tender to tough beef occurred between 4.3 and 4.9 kg of WBS based on > or = 86% consumer acceptability. Consumer acceptability for tenderness decreased from 86% at 4.3 kg for a "slightly tender" rating to 59% at 4.9 kg for a "slightly tough" rating. Data from the present study suggested that consumer WBS tenderness values of < 3.0, 3.4, 4.0, 4.3, and > 4.9 kg would result in 100, 99, 94, 86, and 25% customer satisfaction for beef tenderness, respectively. Seventy-eight percent of the consumers would purchase steaks if the retailer guaranteed them to be tender. The retail steak value differences found in this study would result in the opportunity for a premium to be paid for a guaranteed tender (< 3.0 kg WBS value) carcass of $76.26 vs the toughest (> 5.7 kg) classification. A premium of $66.96 could be paid to the tender classification carcasses vs the tough (> 4.9 kg) classification carcasses, and a premium of $36.58 could be paid for the tender classification carcasses vs the intermediate (> 3.0 to < 4.6 kg) classification carcasses. Results from the present study show that consumers can segregate differences in beef tenderness and that consumers are willing to pay more for more-tender beef. 相似文献
72.
Kerth CR Carr MA Ramsey CB Brooks JC Johnson RC Cannon JE Miller MF 《Journal of animal science》2001,79(9):2346-2355
We examined the effects of vitamin and mineral supplementation of the finishing diet on growth and accelerated chilling of carcasses on carcass and muscle traits of halothane gene carrier and noncarrier pigs. Barrows and gilts that were either monomutants (MON, n = 49) or noncarriers (NON, n = 28) of the halothane gene were fed a standard finishing diet until they reached 86 kg. They then were randomly assigned to one of four finishing diets formulated to contain 11 IU/kg vitamin E (0), 311 IU/kg vitamin E plus additional vitamins and minerals (300), 611 IU/kg vitamin E plus additional vitamins and minerals (600), or 911 IU/kg vitamin E plus additional vitamins and minerals (900) until they were slaughtered (118 kg). Alternating carcass sides were assigned either a normal chilling procedure (NC, 4 degrees C for 24 h) or an accelerated chilling procedure (AC, -20 degrees C for 1.5 h and then 4 degrees C for 22.5 h). Supplementing vitamin E in the finishing diet increased (P < 0.05) the concentration of vitamin E in the longissimus muscle. Supplementing vitamin E in the diets of MON pigs did not affect color, firmness, or cooking losses of loins or color and firmness of hams. For the NON genotype, increasing the level of vitamin E in the diet decreased (P < 0.05) the percentage of PSE loins and hams. Color and firmness scores of the gluteus medius and longissimus muscles were improved 0.4 unit (P < 0.005) by AC compared with NC of carcasses. Loin chop juiciness and flavor were improved (P < 0.05) in the MON genotype for AC compared to NC. Accelerated chilling reduced (P < 0.05) the percentage of PSE loins from 38 to 17% and PSE hams from 32 to 10% for the MON genotype, but percentage of PSE was not affected (P > 0.05) by chilling treatment for the NON genotype. No interaction between diet and chill treatments existed for muscle quality traits (P > 0.05). Supplementing finishing diets of NON pigs with at least 600 IU/kg vitamin E, in addition to other vitamins and minerals, or accelerated chilling of MON carcasses can reduce the incidence of PSE pork. 相似文献
73.
K. L. Christiansen C. L. Weller V. L. Schlegel S. L. Cuppett T. P. Carr 《Cereal Chemistry》2007,84(5):463-470
The objectives of this study were to identify and quantify lipid classes extracted from the stalk, leaves, and the whole kernels of nine different sorghum parent lines. All extractions were performed with a Soxtec using n-hexane as the extraction solvent. Analytical methods including high-performance liquid chromatography (HPLC), gas chromatography (GC), and thin-layer chromatography (TLC) were used to identify and quantify the extracted lipid classes: triacylglycerides (TAG), diglycerides (DG), policosanols (PA), free sterols (FS), phytosterols (PS), free fatty acids (FFA), tocopherols (T), and fatty aldehydes. Overall, extracts from the leaves had higher amounts of soluble matter. Extracts from leaves contained more alcohols and sterols, whereas extracts from the stalks and the whole kernels contained the greatest amount of free fatty acids and fatty aldehydes, respectively. Trace amounts of tocopherol were detected by HPLC in all 27 samples. The lipid profiles of extracts from the whole kernels, leaves, and stalks from the same plant differed. The lipid profiles of extracts from each anatomical part of the sorghum plant differed between the nine parent lines. 相似文献
74.
This paper describes the development of a three-dimensional constitutive model for laminated veneer lumber (LVL) needed for new developments using this material. The LVL was manufactured in New Zealand from Radiata Pine. Experimental testing has been performed according to European timber testing standards. Block compression testing has resulted in modulus of elasticity values in the three material directions. Digital image correlation (DIC) technique has been used to determine the six Poisson’s ratios. Shear testing, whereby timber specimens were glued between two steel plates, has given stiffness values using DIC measurements. Experimental testing results have been compared with values found in literature. Results from this experimental testing programme have made it possible to create a three-dimensional elastic material model of LVL for the use in finite element analysis programmes. Although the material properties do not result in a symmetrical constitutive matrix, only minor adjustments are needed to gain the benefits of a symmetrical matrix. 相似文献
75.
Malathi Erickson Linda M. Hiebert Anthony P. Carr Jocelyn D. Stickney 《Canadian journal of veterinary research》2014,78(3):193-201
The effects of heparin administration, by the oral route, were evaluated in dogs. In single and multiple dose studies (single 7.5 mg/kg, multiple 3 × 7.5 mg/kg per 48 h), plasma, urine, and fecal samples were collected at various times up to 120 h after oral administration of unfractionated heparin. Changes in plasma and urine anti-Xa activity, plasma and urine anti-IIa activity, plasma activated partial thromboplastin time (APTT) and antithrombin (ATIII), and chemical heparin in urine and feces were examined with time. There was support for heparin absorption, with significant differences in APTT, heparin in plasma as determined by anti-Xa activity (Heptest) in the single dose study and plasma anti-Xa activity, anti-IIa activity and ATIII; and chemical heparin in urine in the multiple dose study. No clinical evidence of bleeding was detected in any dog during the studies. Oral heparin therapy may be applicable for thromboembolic disease in animals. Further studies are warranted to determine the effects of oral heparin at the endothelial level in the dog. 相似文献
76.
Hasty R Hawthorne-Allen AM Averett T Barkhuff D Beck DH Beise EJ Blake A Breuer H Carr R Covrig S Danagoulian A Dodson G Dow K Farkhondeh M Filippone BW Gao J Herda MC Ito TM Jones CE Korsch W Kramer K Kowalski S Lee P McKeown RD Mueller B Pitt M 《Science (New York, N.Y.)》2000,290(5499):2117-2119
The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium. 相似文献
77.
Explaining the energetics of walking and running has been difficult because the distribution of energy use among individual muscles has not been known. We estimated energy use by measuring blood flow to the hindlimb muscles in guinea fowl. Blood flow to skeletal muscles is controlled locally and varies directly with metabolic rate. We estimate that the swing-phase muscles consume 26% of the energy used by the limbs and the stance-phase muscles consume the remaining 74%, independent of speed. Thus, contrary to some previous suggestions, swinging the limbs requires an appreciable fraction of the energy used during terrestrial legged locomotion. Models integrating the energetics and mechanics of running will benefit from more detailed information on the distribution of energy use by the muscles. 相似文献
78.
Belton MJ Head JW Pieters CM Greeley R McEwen AS Neukum G Klaasen KP Anger CD Carr MH Chapman CR Davies ME Fanale FP Gierasch PJ Greenberg R Ingersoll AP Johnson T Paczkowski B Pilcher CB Veverka J 《Science (New York, N.Y.)》1992,255(5044):570-576
Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (>2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta. 相似文献
79.
Nakazawa K Quirk MC Chitwood RA Watanabe M Yeckel MF Sun LD Kato A Carr CA Johnston D Wilson MA Tonegawa S 《Science (New York, N.Y.)》2002,297(5579):211-218
Pattern completion, the ability to retrieve complete memories on the basis of incomplete sets of cues, is a crucial function of biological memory systems. The extensive recurrent connectivity of the CA3 area of hippocampus has led to suggestions that it might provide this function. We have tested this hypothesis by generating and analyzing a genetically engineered mouse strain in which the N-methyl-D-asparate (NMDA) receptor gene is ablated specifically in the CA3 pyramidal cells of adult mice. The mutant mice normally acquired and retrieved spatial reference memory in the Morris water maze, but they were impaired in retrieving this memory when presented with a fraction of the original cues. Similarly, hippocampal CA1 pyramidal cells in mutant mice displayed normal place-related activity in a full-cue environment but showed a reduction in activity upon partial cue removal. These results provide direct evidence for CA3 NMDA receptor involvement in associative memory recall. 相似文献
80.
Samuel J. Hornsey Anthony P. Carr Jennifer M. Loewen 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(1):32
A 12-year-old spayed female German shorthaired pointer dog sustained extensive bite wounds around the neck. At presentation, atrial fibrillation was identified with a rapid ventricular response rate of 300 beats per minute (bpm). The ventricular response rate rapidly decreased to 130 bpm following administration of hydromorphone and oxygen. Based on the rate, antiarrhythmic therapy was not initiated. The heart rhythm converted back to sinus rhythm by the time of the first recheck evaluation 2 days later, and the dog remained in sinus rhythm at all subsequent evaluations. With the resolution of the arrhythmia, paroxysmal atrial fibrillation was suspected. The underlying etiology of the arrhythmia was not determined; however, imbalances in autonomic tone associated with trauma and/or direct trauma to the heart were hypothesized.Key clinical message:This report indicates a possible role of imbalances in autonomic tone due to trauma in the development of paroxysmal atrial fibrillation and suggests that it should be a differential diagnostic consideration in patients with atrial fibrillation following trauma. Primary treatment of atrial fibrillation may not be needed in these cases if the ventricular response rate is not rapid, or if there is spontaneous conversion to sinus rhythm. 相似文献