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101.
Low stress pre-slaughter handling: effect of lairage time on the meat quality of pork 总被引:1,自引:0,他引:1
The effect of lairage time on meat quality was investigated when crossbred pigs were subjected to low stress pre-slaughter handling, where pigs were treated in mixed groups of 15 from the farm to group CO(2) stunning, and where electric goads were not used at any time. Two experiments were carried out, one in spring (n=270) using very standardised conditions and one producer, and one in summer (n=630) using a representative randomly chosen sample of producers. In the first experiment three lairage times were used, less than 30 min (average 26 min), 90 min (average 83 min) and more than 150 min (average 170 min) and no showering. The pH and temperature were measured in the m. longissimus dorsi at various times post mortem, and colour (L(*), a(*), b(*)), internal reflectance and drip loss the day after slaughter. Sensory evaluation was carried out on 16 randomly chosen samples from the shortest and longest lairage time groups. Drip loss, pH(ultimate) and internal reflectance were also measured in the m. biceps femoris and pH(ultimate) and internal reflectance in the m. semimembranosus. Finally, pH(ultimate) was measured in the m. semispinalis capitis. In the second experiment only two lairage times were used, less than 30 min (average 17 min) and more than 130 min (average 150 min) and with intermittent showering and only a subset of the meat quality measurements were made. Lairage time had no effect on any of the meat quality parameters measured in experiment 1. In experiment 2 the shortest lairage time led to a higher temperature in the m. longissimus dorsi at 2 min post mortem, a higher drip loss in the m. biceps femoris and higher internal reflectance values in both muscles the day after slaughter. The differences were, however, very small and may have been an effect of showering. 相似文献
102.
Performance of task sequences is assumed to rely on activation and inhibition of tasks. An empirical marker of task inhibition is the so-called n - 2 repetition cost, which is assessed by comparing performance in trial n - 2 task repetitions (i.e., ABA) with that in n - 2 task switches (i.e., CBA). Current theoretical accounts assume that inhibition acts on the level of task representations (i.e., task sets). However, another potential target of task inhibition could be the representation of the task cue. To decide between these two alternatives, the authors used a 2:1 cue-to-task mapping design. They found significant n - 2 task repetition costs both with n - 2 cue repetitions and n - 2 cue switches. These costs were about equal (Experiment 1), and this data pattern was found for both short and long cuing intervals (Experiment 2). Together, the data suggest that task inhibition acts on task sets and not on cue representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Brian J. Driessen Viraja Madhuri Duggirala 《Journal of Intelligent and Robotic Systems》2007,50(2):207-215
In this work, we present an observer and controller for a class of plants with a relatively large class of hysteresis. For
these considered classes of hysteretic systems, we propose and present an observer/controller that estimates or observes the
hysteresis state and drives the position tracking error to zero. We prove that the combined tracking error and observer errors
converge to zero both globally asymptotically and locally exponentially. 相似文献
104.
DE Comings R Gade JP MacMurray D Muhleman WR Peters 《Canadian Metallurgical Quarterly》1996,1(4):325-335
To examine the possible role of genetic variants of the OB gene in obesity we examined alleles of a dinucleotide repeat polymorphism, D7S1875, close to the gene, in a group of adult, non-Hispanic Caucasians. There was a significant correlation with body mass index (BMI) at age 26-30 years for males and females combined (P = 0.04) and females only (P = 0.028). Because of the frequent association between obesity and psychiatric symptoms all subjects were screened with the Symptom List 90 (SCL-90). There was a significant increase in scores for anxiety (P = 0.0005), depression (P = 0.003), and other behaviors for subjects homozygous for the OB1875 < 208-bp alleles. Analysis of covariance indicated that this was directly related to the OB alleles and not secondary to the presence of obesity. There was a significant association between the BMI at ages 16 to 40 and homozygosity for the OB1875 < 208-bp alleles and/or the presence of the DRD2 Taq A1 allele for males and females combined (P = 0.002 to 0.005), and for females alone (P = 0.0017 to 0.0005). For females alone these two genes accounted for up to 22.8% of the variance of the BMI. These results are consistent with the polygenic inheritance of obesity, the greater involvement of genetic factors in women and younger individuals, and suggest that variants of the OB gene are causally involved not only in human obesity but its associated behavioral disorders. 相似文献
105.
106.
J Scott G Gade M McKenzie I Venohr 《Canadian Metallurgical Quarterly》1998,53(5):68-70, 76-8, 81; quiz 82
In cooperative health care clinics (CHCC), health care is provided to older patients in a group setting. The CHCC concept, which was developed under a research grant by Kaiser Permanente in Colorado in 1991, showed improvement in patient and provider satisfaction, as well as improved quality of care and cost effectiveness. CHCC are being replicated in other sites under a research grant from the Robert Wood Johnson Foundation. In addition to formal findings from research studies, much has been learned about factors that have promoted the success of the program. 相似文献
107.
M van de Velde MM van den Berg-Lenssen GJ van Boxtel PJ Cluitmans B Kemp J Gade CE Thomsen A V?rri 《Canadian Metallurgical Quarterly》1998,106(6):547-551
The relationship between sequential mammographic parenchymal patterns and breast cancer was estimated and the results were applied to selective screening. In a pilot screening program 4163 Finnish women aged 40-47 years at entry were invited to be screened every second year from 1982 to 1990. Mammographic parenchymal patterns (Wolfe's classification) were recorded at each screening round. The follow-up ended in 1993 and up until that time 68 new breast cancers were diagnosed. The age-adjusted relative risk of breast cancer was 2.5 (95% CI 1.5-4.0) among women with high-risk mammographic parenchymal patterns (P2,DY) at the screenings preceding cancer diagnosis compared with those with low-risk patterns (N1,P1). After further adjustment for body mass index, number of pregnancies and size of the breast, the relative risk increased to 2.8 (95% CI 1.7-4.9). The mammographic parenchymal pattern is an independent risk factor of breast cancer but not strong enough to be used as a criterion for selective screening. 相似文献
108.
Graph‐theory‐based spectral feature selection for computer aided diagnosis of Parkinson's disease using T1‐weighted MRI 下载免费PDF全文
109.
Sabina K. Gade Matthew K. Keeling Alexander P. Davidson Oyvind Hatlevik J. Douglas Way 《International Journal of Hydrogen Energy》2009
Prior published research has claimed that the addition of 4.5 wt% ruthenium to palladium in dense, cold-worked membranes produces desirable properties for hydrogen separation, including greater mechanical strength and increased hydrogen permeability, particularly at higher temperature ranges. Electroless co-deposition onto porous media can be used to produce high-quality composite membranes which take advantage of both the mechanical strength of the support and the high flux of the thin film. The objectives of this investigation were to fabricate Pd–Ru alloy composite membranes, and to examine their properties. 相似文献
110.
Metal phthalocyanines, possessing rich redox chemistry due to the presence of the central metal cation and pyrrolic nitrogen atoms of the macrocycle, are explored as electrochemical sensors. Nickel phthalocyanine nanofibres (NiPc NF) prepared by a simple chemical route are coated on a pencil graphite rod and the electrocatalytic performance of NiPc NF electrode is investigated for quantitative detection of ascorbic acid (AA) in 0.2 M phosphate buffer solution. The performance of NiPc NFs is shown to be superior to that of commercial NiPc and is attributed to the high electrochemically active surface area available for fibres. The electrode exhibits linearity for the detection over a wide concentration range of AA from \(5.5\,\upmu \hbox {M}\) to 5.2 mM. The detection limit for AA sensing with NiPc-NF-modified electrode is \(1.5\,\upmu \hbox {M}\). The higher performance of NiPc fibres due to its nanostructure morphology may be utilized for the quantitative detection of other biomolecules. 相似文献