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51.
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Hertl JA Schukken YH Bar D Bennett GJ González RN Rauch BJ Welcome FL Tauer LW Gröhn YT 《Journal of dairy science》2011,94(10):4863-4877
The objective of this study was to estimate the effects of recurrent episodes of different types of clinical mastitis (CM) caused by gram-positive (Streptococcus spp., Staphylococcus aureus, Staphylococcus spp.) and gram-negative (Escherichia coli, Klebsiella, Citrobacter, Enterobacter, Pseudomonas) bacteria, and other organisms (Arcanobacterium pyogenes, Mycoplasma, Corynebacterium bovis, yeast, miscellaneous) on the probability of mortality and culling in Holstein dairy cows. Data from 30,233 lactations in cows of 7 dairy farms in New York State were analyzed. Cows were followed for the first 10 mo in lactation, or until death or culling occurred, or until the end of our study period. Generalized linear mixed models with a Poisson error distribution were used to study the effects of recurrent cases of the different types of CM and several other factors (herd, parity, month of lactation, current year and season, profitability, net replacement cost, other diseases) on cows’ probability of death (model 1) or being culled (model 2). Primiparous and multiparous cows were modeled separately because they had different risks of mortality and culling and potentially different CM effects on mortality and culling. Approximately 30% of multiparous cows had at least one case of CM in lactation compared with 16.6% of primiparous cows. Multipara also had higher lactational incidence risks of second (10.7%) and third (4.4%) cases than primipara (3.7% and 1.1%, respectively). For primipara, CM increased the probability of death, with each successive case occurring in a month being increasingly lethal. In multipara, gram-negative CM increased the probability of death, especially when the gram-negative case was the first or second CM case in lactation. Primiparous cows with CM were more likely to be culled after CM than if they did not have CM, particularly after a second or third case. In multipara, any type of CM increased the probability of being culled. Gram-negative CM cases were associated with the numerically highest risk of culling. 相似文献
53.
Collinear or near collinear placement of some sensors in a wireless sensor network causes the location estimates of nearby
sensors to be sensitive to erroneous distance measurements which leads to large location estimation errors. These errors and
the possible propagation of these errors to the entire network or a large portion of it, thereby causing larger estimation
errors for some sensors’ locations, is a major problem in localization. This phenomenon is well described in rigid graph theory,
using the notion of “flip ambiguity”. This paper considers arbitrary sensor neighborhoods of two dimensional sensor networks
and formulates an analytical expression for the probability of occurrence of the flip ambiguity. Based on the derived probability
expression, a methodology is proposed to make the localization algorithms robust by calculating such flip ambiguity probabilities
and eliminating potentially poor location estimates as well as assigning confidence factors to the estimated locations to
prevent them from ruining the subsequent localization steps. The efficiency of the proposed methodology is demonstrated via
a set of simulations. 相似文献
54.
Platelet adenylyl cyclase (AC) activity was measured in 32 alcohol-dependent subjects and 27 control subjects who were categorized as either family history-positive (FHP) or family history-negative (FHN) for alcoholism. The interview and blood sample collections were performed shortly after cessation of heavy drinking in the alcoholic group, and repeat blood samples were obtained at the end of the first and second weeks of monitored abstinence. Control subjects received the same interview and provided blood samples at the time of the interview. When subjects were not segregated for FHP or FHN status, there were no statistically significant differences in basal, cesium fluoride (CsF)-, or forskolin-stimulated mean AC activities between the controls and the alcoholics, at study entry or with 1 or 2 weeks of abstinence. On the other hand, over the 2-week course of sobriety from heavy drinking, the CsF-stimulated AC activity of FHP alcohol-dependent subjects decreased significantly (p = 0.03). FHP alcohol-dependent subjects after 2 weeks of sobriety had significantly lower mean CsF-stimulated AC activity than FHN controls (p = 0.04), whereas the FHN alcoholic subjects' CsF-stimulated AC activity did not differ significantly from FHN controls at this point in time. When all subjects were pooled and then categorized as either FHP or FHN, there was a significant difference in mean CsF-stimulated AC activity (p = 0.02) between the FHP and FHN subject groups. Genetic factors and abstinence appear to have roles in determining low platelet AC activity in alcoholic and nonalcoholic subjects. CsF-stimulated platelet AC activity, in particular, appears to act as a trait marker for a genetic vulnerability to developing alcoholism, but recent heavy drinking in male alcoholics is a factor that can mask differences between FHP and FHN subjects. 相似文献
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Microalbuminuria is defined as urinary excretion of albumin that is persistently above normal, although below the sensitivity of conventional semiquantative test strips. Several studies have reported that Type 1 diabetic patients with microalbuminuria are apparently more likely to develop diabetic nephropathy eventually progressing to renal failure. Microalbuminuria is also a strong predictor of mortality in Type 2 diabetes, and is correlated with increased blood pressure in patients with benign essential hypertension. Radioimmunoassay revealed a significantly higher urinary albumin excretion rate in normal pregnant women in the third trimester of pregnancy, compared to the second and first, and compared to non-pregnant women. Microalbuminuria was found in 30% of women who had a record of gestational diabetes mellitus. Published results are controversial regarding the assumption that microalbuminuria is an early predictor of pregnancy-induced hypertensive complications. 相似文献
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Business process reengineering (BPR) and systems reengineering (SR) often are implemented separately, in an uncoordinated fashion. Yet practitioners realize that BPR can be informed by SR and that SR can benefit from the application of BPR concepts. This article presents an integrated BPR and SR model that exploits the synergy of integrated BDR and SR. the model has been applied successfully in practice and shows how to tailor this model to meet each organization's situation. 相似文献
60.
Williams Tannis M.; Fryer Margaret L.; Aiken Leona S. 《Canadian Metallurgical Quarterly》1977,13(6):577
Studied the use of prototypes and distinctive features in visual pattern classification with 12 Ss at each of 3 age levels: 4, 5, and 6 yrs. All Ss attended day-care centers in middle-class neighborhoods of metropolitan Canadian areas. Two tasks were performed: (a) an oddity task requiring selection of the odd pattern in problems containing 2 patterns generated from 1 prototype and 1 from another, and (b) a sequential task requiring designation from memory of each pattern's class membership. There was a marked improvement in oddity task classification accuracy between the 4- and 5-yr age levels. Performance at each age level could be predicted from measures of deviation from prototype and 2 distinctive features unrelated to pattern class membership. In the more difficult sequential task, the preschoolers did not respond to an entire set of features as subsumed in prototype measures, but a single class-defining feature significantly predicted the classifications of the 4- and 5-yr-olds. It is concluded that the ability to use single features develops prior to the ability to use a feature list or prototype and that both distinctive features and prototypes are important for perceptual learning and development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献