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1.
Science ; 315(5810): 342-3, 2007 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-17234938
2.
J Anim Sci ; 83(12): 2869-75, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16282626

RESUMO

The objectives of this study were to evaluate whether instructions can help consumers properly prepare top sirloin steaks and to evaluate the use of calcium chloride injection to decrease the sensitivity of top sirloin steaks to degree of doneness, thereby improving customer satisfaction ratings. An in-home study evaluated top sirloin steaks (gluteus medius) as influenced by calcium chloride injection (injected vs. noninjected), consumer segment (beef loyalists = heavy consumers of beef, budget rotators = cost-driven and split meat consumption between beef and chicken, and variety rotators = higher incomes and education and split meat consumption among beef, poultry, and other foods), degree of doneness, cooking method, and instructions (given vs. not given). Consumers evaluated overall like, tenderness, juiciness, flavor like, and flavor amount using 10-point scales. Beef loyalists consistently rated steaks higher for overall like, juiciness, and flavor when instructions were provided (P < 0.05) and rated top sirloin steaks higher for overall like and tenderness when given instructions for grilling (P < 0.05). Budget rotators and variety rotators rated steaks differently among cooking methods (P < 0.05). Correlation and stepwise regression analyses indicated that flavor like was the most highly correlated with overall like, followed by tenderness, flavor amount, and juiciness. Calcium chloride injection had no effect on consumers' likes or dislikes or on tenderness (P < 0.05). For top sirloin steaks, it was likely that preparation played a major role in consumer satisfaction, and beef loyalists benefited the most from providing cooking instructions.


Assuntos
Cloreto de Cálcio , Comportamento do Consumidor , Culinária , Carne/normas , Animais , Bovinos
3.
J Anim Sci ; 83(3): 662-70, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15705763

RESUMO

An in-home beef study evaluated consumer ratings of top round steaks (semimembranosus) as influenced by USDA quality grade (top Choice or high Select), city (Chicago or Philadelphia), consumer segment (beef loyalists = heavy consumers of beef; budget rotators = cost-driven and split meat consumption between beef and chicken; and variety rotators = higher incomes and education and split meat consumption among beef, poultry, and other foods), degree of doneness, cooking method, and marination. Consumers evaluated each steak for overall like, tenderness, juiciness, flavor like, and flavor amount using 10-point scales (1 = dislike extremely, not at all tender, not at all juicy, dislike extremely, and none at all to 10 = like extremely, extremely tender, extremely juicy, like extremely, and an extreme amount of flavor, respectively). Quality grade affected several consumer sensory traits, with top Choice receiving higher (P < or = 0.004) tenderness, juiciness, and flavor like scores than high Select. Consumers in Chicago rated steaks cooked "medium and less" higher for overall like, tenderness, juiciness, flavor like, and flavor amount than those in Philadelphia (city x degree of doneness; P < or = 0.020). Steaks braised by customers in Philadelphia received among the highest scores for overall like, tenderness, juiciness, flavor like, and flavor amount compared with any cooking method used by customers in Chicago (cooking method x city; P < or = 0.026). Overall like and flavor amount ratings were least (P < 0.05) for steaks that were marinated and cooked to "medium and less" degree of doneness (marination x degree of doneness; P < or = 0.014). Braised steaks received among the highest values for overall like, tenderness, juiciness, flavor like, and flavor amount when cooked to "medium and less" or "medium well and more" (cooking method x degree of doneness; P < or = 0.008). Correlation and stepwise regression analysis indicated that flavor like was pivotal in customers' satisfaction with top round steaks, and was the sensory trait most highly correlated to overall like, followed by tenderness, flavor amount, and juiciness. Preparation of top round steaks was crucial in consumers' likes and dislikes, and by improving flavor, higher consumer satisfaction may be achieved.


Assuntos
Bovinos , Comportamento do Consumidor , Culinária/normas , Manipulação de Alimentos/métodos , Carne/normas , Animais , Chicago , Culinária/classificação , Culinária/métodos , Carne/classificação , Carne/economia , Philadelphia , Análise de Regressão , Estatística como Assunto , Paladar , Estados Unidos , United States Department of Agriculture/normas
4.
Neurology ; 63(3): 485-91, 2004 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15304579

RESUMO

OBJECTIVE: To determine the prevalence and risk factors of deep vein thrombosis (DVT) among neurorehabilitation admissions with acquired brain injury (BI). METHODS: In this prospective, sequential case series, 709 consecutive initial neurorehabilitation patients with BI < 120 days-including traumatic brain injury (TBI; n = 360), intracranial hemorrhage (ICH; n = 213), primary brain tumor (n = 66), and hypoxia/other BI (n = 70)--were screened for evidence of DVT with lower extremity venous duplex ultrasonography (VDU). The admission screening protocol combined VDU and a commercial d-dimer (Dimertest [DDLx]) latex agglutination assay. DVT was considered present based upon VDU results only. RESULTS: DVT prevalence was 11.1%, and was higher with brain tumor (21.2%) and ICH (16%) than with TBI (6.7%) (chi2 test; p = 0.001). DVT risk factors identified by multivariable logistic regression analysis in the overall sample included older age (p = 0.002), type of BI (p = 0.04), DDLx (p = 0.0001), and greater postinjury duration (p = 0.0001), with a trend observed regarding lower Functional Independence Measure (FIM) locomotion (FIM-Loco) subscale score (p = 0.07). However, risk factors also varied with type of BI. Among patients with TBI, only DDLx (p = 0.001) and greater postinjury duration (p = 0.001) were associated with DVT. CONCLUSIONS: Admission venous duplex ultrasonography revealed occult proximal lower extremity deep vein thrombosis in 11% of neurorehabilitation patients with acquired brain injury. Deep vein thrombosis risk is multifactorial in this heterogenous patient population, with relative factor risk influenced by type of acquired brain injury. Semiquantitative d-dimer latex agglutination assay correlated significantly with presence of deep vein thrombosis.


Assuntos
Lesões Encefálicas/complicações , Trombofilia/complicações , Trombose Venosa/epidemiologia , Adolescente , Adulto , Idoso , Lesões Encefálicas/reabilitação , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/reabilitação , Hemorragia Cerebral/complicações , Hemorragia Cerebral/reabilitação , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Hipóxia Encefálica/complicações , Hipóxia Encefálica/reabilitação , Perna (Membro)/irrigação sanguínea , Perna (Membro)/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Ultrassonografia Doppler Dupla , Trombose Venosa/sangue , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia
5.
Anal Chem ; 76(14): 4011-6, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15253636

RESUMO

We have fabricated a low-cost disposable polymerase chain reaction thermal chamber that uses buoyancy forces to move the sample solution between the different temperatures necessary for amplification. Three-dimensional, unsteady finite element modeling and a simpler 1-D steady-state model are used together with digital particle image velocimetry data to characterize the flow within the device. Biological samples have been amplified using this novel thermal chamber. Time for amplification is less than 30 min. More importantly, an analysis of the energy consumption shows significant improvements over current technology.


Assuntos
Reação em Cadeia da Polimerase/instrumentação , Fontes de Energia Elétrica , Reação em Cadeia da Polimerase/métodos , Fatores de Tempo
6.
J Anim Sci ; 80(2): 401-8, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11881929

RESUMO

An in-home beef study evaluated consumer ratings of clod steaks (n = 1,264) as influenced by USDA quality grade (Top Choice, Low Choice, High Select, and Low Select), city (Chicago and Philadelphia), consumer segment (Beef Loyals, who are heavy consumers of beef; Budget Rotators, who are cost-driven and split meat consumption between beef and chicken; and Variety Rotators, who have higher incomes and education and split their meat consumption among beef, poultry, and other foods), degree of doneness, and cooking method. Consumers evaluated each steak for Overall Like, Tenderness, Juiciness, Flavor Like, and Flavor Amount using 10-point scales. Grilling was the predominant cooking method used, and steaks were cooked to medium-well and greater degrees of doneness. Interactions existed involving the consumer-controlled factors of degree of doneness and(or) cooking method for all consumer-evaluated traits for the clod steak (P < 0.05). USDA grade did not affect any consumer evaluation traits or Warner-Bratzler shear force values (P > 0.05). One significant main effect, segment (P = 0.006), and one significant interaction, cooking method x city (P = 0.0407), existed for Overall Like ratings. Consumers in the Beef Loyals segment rated clod steaks higher in Overall Like than the other segments. Consumers in Chicago tended to give more uniform Overall Like ratings to clod steaks cooked by various methods; however, consumers in Philadelphia gave among the highest ratings to clod steaks that were fried and among the lowest to those that were grilled. Additionally, although clod steaks that were fried were given generally high ratings by consumers in Philadelphia, consumers in Chicago rated clod steaks cooked in this manner significantly lower than those in Philadelphia. Conversely, consumers in Chicago rated clod steaks that were grilled significantly higher than consumers in Philadelphia. Correlation and stepwise regression analyses indicated that Flavor Like was driving customer satisfaction of the clod steak. Flavor Like was the sensory trait most highly correlated to Overall Like, followed by Tenderness, Flavor Amount, and Juiciness. Flavor Like was the first variable to enter into the stepwise regression equation for predicting Overall Like, followed by Tenderness and Flavor Amount. For the clod steak, it is likely that preparation techniques that improve flavor without reducing tenderness positively affect customer satisfaction.


Assuntos
Comportamento do Consumidor , Manipulação de Alimentos/métodos , Carne/normas , Adulto , Animais , Bovinos , Chicago , Análise por Conglomerados , Culinária/métodos , Coleta de Dados , Humanos , Carne/economia , Philadelphia , Paladar
7.
Meat Sci ; 58(4): 381-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22062428

RESUMO

Dorset×Suffolk crossbred wethers expressing a normal phenotype (normal, n=10) and callipyge phenotype (CLPG, n=9) were fed individually and slaughtered upon reaching maximum growth potential. Carcass weight did not differ (P>0.05), but fat thickness was lower (0.30 vs. 0.56 cm), ribeye area was greater (24.4 vs. 16.6 cm(2)), and USDA yield grade was improved (1.6 vs. 2.6) for CLPG carcasses (P < 0.05). Carcasses from CLPG demonstrated higher cutability and a more desirable muscle to bone ratio, with less fat and more lean as a percentage of total side weight (P<0.05). Biceps femoris (BF), semitendinosus (ST), semimembranosus (SM), longissimus thoracis et lumborum (LTL), and triceps brachii (TB) were used to compare muscle characteristics of both phenotypes. Muscle from normal lambs had lower calpastatin activity, higher fat percentages and lower moisture percentages (P<0.05). Total amount and solubility of collagen were not affected by phenotype nor was sarcomere length. Shear force and trained sensory attributes were evaluated for BF and LTL only. Shear force values did not differ between normal and CLPG BF while CLPG LTL had higher (P< 0.05) shear force values than normal LTL. Biceps femoris did not differ between phenotypes in trained sensory panel ratings. However, CLPG LTL received the lowest sensory ratings for connective tissue amount and myofibrillar and overall tenderness (6.11, 4.97, and 4.95, respectively) and the normal LTL received the highest ratings (P < 0.05; 7.10, 7.00, and 6.90, respectively). The CLPG phenotype had a positive influence on carcass characteristics but had a negative influence on tenderness of some muscles, possibly through the myofibrillar component of the muscle.

8.
Opt Lett ; 26(7): 399-401, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18040333

RESUMO

Light focused from air into a spherical microlens is affected by diffraction at the lens surface as its diameter approaches the wavelength of light. Through an extension of Mie theory, we show that a converging wave that is incident upon a Si microlens with a diameter less than approximately 4lambda creates a spot as much as 25% smaller than predicted with vector diffraction theory. Si microlenses only a wavelength in diameter are shown to be virtually insensitive to variations in the maximum illumination angle, and changes in index of refraction are not found to cause the proportional changes in spot size that would be expected from vector diffraction theory.

9.
J Food Prot ; 62(2): 146-51, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10030633

RESUMO

Hot beef carcass surface regions (outside round, brisket, and clod) contaminated with feces spread over a 5-cm2 (1-in2) area were cleaned using a steam-vacuum spot-cleaning system alone or combined with subsequent sanitizing treatments of hot water (95 degrees C at the nozzle), or warm (55 degrees C) 2% lactic acid spray, or combinations of these two sanitizing methods. These treatments were compared for effectiveness in reducing aerobic plate counts (APC) and counts of Enterobacteriaceae, total coliforms, thermotolerant coliforms, and Escherichia coli. All treatments significantly reduced the numbers of each group of bacteria on beef carcass surfaces. However, reductions obtained by steam vacuuming were significantly smaller than those obtained by a combination of steam vacuuming with any sanitizing treatment. No differences in bacterial reductions were observed between different carcass surface regions. Steam vacuuming reduced the number of different indicator organisms tested by ca. 3.0 log cycles but also spread the bacterial contamination to areas of the carcass surface adjacent to the contaminated sites. This relocated contamination after steam vacuuming was most effectively reduced by spraying with hot water and then lactic acid. This combined treatment consistently reduced the numbers of Enterobacteriaceae, total and thermotolerant coliforms, and E. coli to undetectable levels (<1.0 log10 CFU/cm2) on areas outside the initial 5-cm2 inoculated areas.


Assuntos
Matadouros/normas , Descontaminação/métodos , Temperatura Alta , Ácido Láctico , Carne/microbiologia , Vapor , Animais , Bactérias Aeróbias/isolamento & purificação , Bovinos , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Microbiologia de Alimentos , Vácuo , Água
10.
J Food Prot ; 61(1): 19-25, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9708247

RESUMO

Hot water treatment of beef carcass surfaces for reduction of Escherichia coli O157:H7, Salmonella typhimurium, and various indicator organisms was studied using a model carcass spray cabinet. Paired hot carcass surface regions with different external fat characteristics (inside round, outside round, brisket, flank, and clod) were removed from carcasses immediately after the slaughter and dressing process. All cuts were inoculated with bovine feces containing 10(6)/g each of rifampicin-resistant E. coli O157:H7 and S. typhimurium, or with uninoculated bovine feces. Surfaces then were exposed to a carcass water wash or a water wash followed by hot water spray (95 degrees C). Counts of rifampicin-resistant Salmonella and E. coli or aerobic plate count (APC) and coliform counts were conducted before and after each treatment. All treatments significantly reduced levels of pathogens from the initial inoculation level of 5.0 log(10) CFU/cm2. Treatments including hot water sprays provided mean reductions of initial counts for E. coli O157:H7 and S. typhimurium of 3.7 and 3.8 log, APC reductions of 2.9 log, and coliform and thermotolerant coliform count reductions of 3.3 log. The efficacy of hot water treatments was affected by the carcass surface region, but not by delaying the treatment (30 min) after contaminating the surface. Verification of efficacy of hot water interventions used as critical control points in a hazard analysis critical control point (HACCP) system may be possible using coliform counts.


Assuntos
Descontaminação/métodos , Temperatura Alta , Carne/microbiologia , Água , Animais , Bactérias Aeróbias/crescimento & desenvolvimento , Bovinos , Contagem de Colônia Microbiana , Descontaminação/instrumentação , Enterobacteriaceae/crescimento & desenvolvimento , Escherichia coli O157/crescimento & desenvolvimento , Fezes/microbiologia , Microbiologia de Alimentos , Salmonella typhimurium/crescimento & desenvolvimento
11.
J Food Prot ; 61(7): 823-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9678163

RESUMO

Cleaning treatments, such as high-pressure water wash at 35 degrees C or trim, alone and combined with sanitizing treatments, such as hot water (95 degrees C at the source), warm (55 degrees C) 2% lactic acid spray, and combinations of these two sanitizing methods, were compared for their effectiveness in reducing inoculated numbers (5.0 to 6.0 log CFU/cm2) of Salmonella typhimurium, Escherichia coli O157:H7, aerobic plate counts, Enterobacteriaceae, total coliforms, thermotolerant coliforms, and generic E. coli on hot beef carcass surface areas in a model carcass spray cabinet. Log reductions in numbers of all tested organisms by water wash or trim alone were significantly smaller than the log reductions obtained by the different combined treatments. Regardless of the cleaning treatment (water wash or trim) or surface area, the range for mean log reductions by hot water was from 4.0 to > 4.8 log CFU/cm2, by lactic acid spray was from 4.6 to > 4.9 log CFU/cm2, by hot water followed by lactic acid spray was from 4.5 to > 4.9 log CFU/cm2, and by lactic acid spray followed by hot water was from 4.4 to > 4.6 log CFU/cm2, for S. typhimurium and E. coli O157:H7. Identical reductions were obtained for thermotolerant coliforms and generic E. coli. No differences in bacterial reductions were observed for different carcass surface regions. Water wash and trim treatments caused spreading of the contamination to other areas of the carcass surface while providing an overall reduction in fecal or pathogenic contamination on carcass surface areas. This relocated contamination after either water wash or trim was most effectively reduced by following with hot water and then lactic acid spray. This combined treatment yielded 0% positive samples for S. typhimurium, E. coli O157:H7, thermotolerant coliforms, and generic E. coli on areas outside the inoculated areas, whereas percent positive samples after applying other combined treatments ranged from 22 to 44% for S. typhimurium, 0 to 44% for E. coli O157:H7, and 11 to 33% for both thermotolerant coliforms and generic E. coli. From data collected in this study, it is possible to choose an effective, inexpensive treatment to reduce bacterial contamination on beef carcasses. In addition, the similar reduction rates of total coliforms, thermotolerant coliforms, or generic E. coli may be useful in identifying an indicator to verify the effectiveness of the selected treatment as a critical control point in a Hazard Analysis and Critical Control Point program.


Assuntos
Bactérias/isolamento & purificação , Bovinos/microbiologia , Fezes/microbiologia , Ácido Láctico/farmacologia , Saneamento , Animais , Escherichia coli O157/isolamento & purificação , Salmonella typhimurium/isolamento & purificação
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