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排序方式: 共有115条查询结果,搜索用时 31 毫秒
71.
Juárez M Caine WR Dugan ME Hidiroglou N Larsen IL Uttaro B Aalhus JL 《Meat science》2011,88(1):117-121
Presumably, dry-ageing enhances flavour attributes of meat by surface desiccation to increase and modify fatty acid content and other organoleptic molecules. However information regarding dry-ageing of fresh pork is limited. To examine the effects of dry-ageing on pork quality, Large White (LW, n = 24) and Large White × Duroc (Duroc, n = 24) barrows were slaughtered and three longissimus thoracis et lumborum sections from each side of the carcass were wet or dry-aged for 2, 7 or 14 d. Dry-aged meat had lower (P < 0.001) moisture and higher (P < 0.001) protein content due to higher purge losses (P < 0.001) when compared with wet aged meat. However no dry-ageing effect (P > 0.05) was observed on sensory characteristics. The increase in the duration of ageing decreased moisture content and drip loss and increased (P < 0.001) protein content, purge loss and L*, chroma and hue values. These changes were more accentuated in dry-aged meat (P < 0.01). Days of ageing dependent increases (P < 0.001) were observed for instrumental and sensory tenderness and juiciness in both ageing types. Moreover, meat from Duroc barrows had lower (P < 0.001) moisture and protein content, and higher (P < 0.01) fat content, L* and hue values. Instrumental and sensory tenderness, juiciness and flavour were higher (P < 0.01) in meat from Duroc than LW barrows. Increases (P < 0.01) in flavour intensity and decreases in off-flavour of meat from LW barrows were greater (P < 0.05) in d 7 than in d 14. Therefore the duration of ageing affected most quality and sensory characteristics, while the changes to quality attributes of dry versus wet-aged pork were attributable to the differences in shrink losses in the present study. 相似文献
72.
Teachman Bethany A.; Gapinski Kathrine D.; Brownell Kelly D.; Rawlins Melissa; Jeyaram Subathra 《Canadian Metallurgical Quarterly》2003,22(1):68
Three studies investigated implicit biases, and their modifiability, against overweight persons. In Study 1 (N=144), the authors demonstrated strong implicit anti-fat attitudes and stereotypes using the Implicit Association Test, despite no explicit anti-fat bias. When participants were informed that obesity is caused predominantly by overeating and lack of exercise, higher implicit bias relative to controls was produced; informing participants that obesity is mainly due to genetic factors did not result in lower bias. In Studies 2A (N=90) and 2B (N=63), participants read stories of discrimination against obese persons to evoke empathy. This did not lead to lower bias compared with controls but did produce diminished implicit bias among overweight participants, suggesting an in-group bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Brand Bethany; Classen Catherine; Lanius Ruth; Loewenstein Richard; McNary Scot; Pain Clare; Putnam Frank 《Canadian Metallurgical Quarterly》2009,1(3):205
Reports an error in "A naturalistic study of dissociative identity disorder and dissociative disorder not otherwise specified patients treated by community clinicians" by Bethany Brand, Catherine Classen, Ruth Lanins, Richard Loewenstein, Scott McNary, Claire Pain and Frank Putnam (Psychological Trauma: Theory, Research, Practice, and Policy, 2009[Jun], Vol 1[2], 153-171). Author Ruth Lanius’s name was misspelled as Ruth Lanins; author Scot McNary’s name was misspelled Scott McNary; author Clare Pain’s name was misspelled Claire Pain; and the affiliation for Richard Loewenstein should have read Sheppard Pratt Health System. (The following abstract of the original article appeared in record 2009-08949-005.) The goals of this naturalistic, cross-sectional study were to describe the patient, therapist, and therapeutic conditions of an international sample of dissociative disorder (DD) patients treated by community therapists and to determine if community treatment for DD appears to be as effective as treatment for chronic PTSD and conditions comorbid with DD. Analyses found that across both patient (N = 280) and therapist (N = 292) reports, patients in the later stages of treatment engaged in fewer self-injurious behaviors, had fewer hospitalizations, and showed higher levels of various measures of adaptive functioning (e.g., GAF) than those in the initial stage of treatment. Additionally, patients in the later stages of treatment reported lower symptoms of dissociation, posttraumatic stress disorder, and distress than patients in the initial stage of treatment. The effect sizes for Stage 5 versus Stage 1 differences in DD treatment were comparable to those published for chronic PTSD associated with childhood trauma and depression comorbid with borderline personality disorder. Given the prevalence, severity, chronicity, and high health care costs associated with DD, these results suggest that extended treatment for DD may be beneficial and merits further research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Compared with what? The effects of different comparisons on conceptual knowledge and procedural flexibility for equation solving. 总被引:1,自引:0,他引:1
Researchers in both cognitive science and mathematics education emphasize the importance of comparison for learning and transfer. However, surprisingly little is known about the advantages and disadvantages of what types of things are being compared. In this experimental study, 162 seventh- and eighth-grade students learned to solve equations (a) by comparing equivalent problems solved with the same solution method, (b) by comparing different problem types solved with the same solution method, or (c) by comparing different solution methods to the same problem. Students’ conceptual knowledge and procedural flexibility were best supported by comparing solution methods and to a lesser extent by comparing problem types. The benefits of comparison are augmented when examples differ on relevant features, and contrasting methods may be particularly useful in mathematics learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Does comparing solution methods facilitate conceptual and procedural knowledge? An experimental study on learning to solve equations. 总被引:1,自引:0,他引:1
Encouraging students to share and compare solution methods is a key component of reform efforts in mathematics, and comparison is emerging as a fundamental learning mechanism. To experimentally evaluate the effects of comparison for mathematics learning, the authors randomly assigned 70 seventh-grade students to learn about algebra equation solving by either (a) comparing and contrasting alternative solution methods or (b) reflecting on the same solution methods one at a time. At posttest, students in the compare group had made greater gains in procedural knowledge and flexibility and comparable gains in conceptual knowledge. These findings suggest potential mechanisms behind the benefits of comparing contrasting solutions and ways to support effective comparison in the classroom. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
The effect of hardhats on head and neck response to vertical impacts from large construction objects
Bethany L. Suderman Ryan W. Hoover Randal P. Ching Irving S. Scher 《Accident; analysis and prevention》2014
We evaluated the effectiveness of hardhats in attenuating head acceleration and neck force in vertical impacts from large construction objects. Two weight-matched objects (lead shot bag and concrete block) weighing 9.1 kg were dropped from three heights (0.91 m, 1.83 m and 2.74 m) onto the head of a 50th percentile male Hybrid III anthropomorphic test device (ATD). Two headgear conditions were tested: no head protection and an ANSI Type-I, Class-E hardhat. A third headgear condition (snow sport helmet) was tested at 1.83 m for comparison with the hardhat. Hardhats significantly reduced the resultant linear acceleration for the concrete block impacts by 70–95% when compared to the unprotected head condition. Upper neck compression was also significantly reduced by 26–60% with the use of a hardhat when compared to the unprotected head condition for the 0.91 and 1.83 m drop heights for both lead shot and concrete block drop objects. In this study we found that hardhats can be effective in reducing both head accelerations and compressive neck forces for large construction objects in vertical impacts. 相似文献
77.
The discovery of dissolved arsenic in a coastal aquifer used extensively for human consumption has led to widespread concern for its potential occurrence in other sandy coastal environments in eastern Australia. The development of an aquifer specific geomorphic model (herein) suggests that arsenic is regionally derived from erosion of arsenic-rich stibnite (Sb(2)S(3)) mineralisation present in the hinterland. Fluvial processes have transported the eroded material over time to deposit an aquifer lithology elevated in arsenic. Minor arsenic contribution to groundwater is derived from mineralised bedrock below the unconsolidated aquifer. An association with arsenic and pyrite has been observed in the aquifer in small discrete arsenian pyrite clusters rather than actual acid sulfate soil horizons. This association is likely to influence arsenic distribution in the aquifer, but is not the dominant control on arsenic occurrence. Arsenic association with marine clays is considered a function of their increased adsorptive capacity for arsenic and not solely on the influence of sea level inundation of the aquifer sediments during the Quaternary Period. These findings have implications for, but are not limited to, coastal aquifers. Rather, any aquifer containing sediments derived from mineralised provenances may be at risk of natural arsenic contamination. Groundwater resource surveys should thus incorporate a review of the aquifer source provenance when assessing the likely risk of natural arsenic occurrence in an aquifer. 相似文献
78.
A series of m-xylene/NO(x) photooxidation experiments were conducted to determine the influence of light intensity and radiation spectrum on secondary organic aerosol (SOA) formation within the UC Riverside/CE-CERT environmental chamber. The environmental chamber is equipped with 80 115-W black lights and a variable voltage 200 kW argon arc lamp that emits a wavelength spectrum more similar to natural light. SOA formation increased significantly with light intensity, measured as the photolysis rate of NO2 to NO (k1), increased from 0.09 to 0.26 min(-1). The argon arc lamp produced approximately 20% more SOA than black lights at a k1 of 0.09 min(-1) for similar amounts of m-xylene consumed. These results may help explain the variation of SOA formation between environmental chambers and the differences between measured SOA in the ambient atmosphere versus environmental chamber predictions. 相似文献
79.
Teachman Bethany A.; Siedlecki Karen L.; Magee Joshua C. 《Canadian Metallurgical Quarterly》2007,22(1):160
Negative affect measures were evaluated in a cross-sectional community sample of adults aged 18-93 (N = 335) to examine the structure of neuroticism, anxiety, and depressive symptoms in young, middle, and older adult cohorts. Structural equation modeling was used to contrast 3 nested models: a 1-factor general distress model; a 2-factor high negative-low positive affect model; and a 3-factor "tripartite model" reflecting a higher order Negative Affect factor that is common to depression and anxiety problems and 2 lower order factors, Low Positive Affect (mostly specific to depression) and Arousal (specific to anxiety/panic). As expected, the tripartite model fit best for all age groups. Further, multigroup analyses indicated age invariance for the tripartite model, suggesting the model can be effectively applied with older populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Nock Matthew K.; Holmberg Elizabeth B.; Photos Valerie I.; Michel Bethany D. 《Canadian Metallurgical Quarterly》2007,19(3):309
The authors developed the Self-Injurious Thoughts and Behaviors Interview (SITBI) and evaluated its psychometric properties. The SITBI is a structured interview that assesses the presence, frequency, and characteristics of a wide range of self-injurious thoughts and behaviors, including suicidal ideation, suicide plans, suicide gestures, suicide attempts, and nonsuicidal self-injury (NSSI). This initial study, based on the administration of the SITBI to 94 adolescents and young adults, suggested that the SITBI has strong interrater reliability (average κ = .99, r = 1.0) and test-retest reliability (average κ = .70, intraclass correlation coefficient = .44) over a 6-month period. Moreover, concurrent validity was demonstrated via strong correspondence between the SITBI and other measures of suicidal ideation (average κ = .54), suicide attempt (κ = .65), and NSSI (average κ = .87). The authors concluded that the SITBI uniformly and comprehensively assesses a wide range of self-injury-related constructs and provides a new instrument that can be administered with relative ease in both research and clinical settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献