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91.
The 2 studies described investigated seasonal variations of mortality and temperature-humidity index (THI)-mortality relationships in dairy cows. Mortality data were extracted from the Italian Bovine Spongiform Encephalopathy databases, which contain records on cows older than 24 mo that died on a farm from all causes (98% of total records), were slaughtered in an emergency state, or were sent for normal slaughter but were sick in the preslaughter inspection (2% of total records). Both studies evaluated mortality data during a 6-yr period (2002 to 2007). The seasonal pattern study was conducted throughout Italy and was based on 320,120 deaths. An association between season and deaths was found for all 6 yr. Summer and spring were the seasons with the highest and lowest frequency of deaths (15,773.3 ± 2,861 and 11,619.3 ± 792.3), respectively, and within summer months, the number of deaths in July and August (5,435 ± 284 and 5,756 ± 676.2, respectively) was higher than in June (4,839 ± 344.8). The THI-mortality relationships study was carried out only for deaths (51,240) reported for the Lombardia and Emilia Romagna regions. For this study, the mortality databases were integrated with THI data, which were calculated by using data from 73 weather stations. Each farm where deaths were recorded was assigned the THI values (maximum and minimum) calculated at the closest weather station for each day the events (deaths) were reported. Analysis of data indicated that approximate THI values of 80 and 70 were the maximum and minimum THI, respectively, above which the number of deaths in dairy farms starts to increase. Maximum and minimum THI values of 87 and 77 were the upper critical THI above which the risk of death for dairy cows becomes maximum. This study defined quantitative relationships between mortality risk and THI in dairy cows and may help to provide emergency interventions and mitigation measures, which may ensure survival of dairy cows and reduce replacement costs associated with heat stress-related mortality. 相似文献
92.
Nathalia Aceval Arriola Gielen Delfino dos Santos Elane Schwinden Prudêncio Luciano Vitali José Carlos Cunha Petrus Renata D. M. Castanho Amboni 《International Journal of Food Science & Technology》2014,49(9):2052-2060
The aim of this study was to evaluate the potential of nanofiltration for the concentration of bioactive compounds of watermelon juice. Lipophilic and hydrophilic antioxidant activities were determined through two assays, ferric reducing antioxidant power and DPPH. The content of lycopene, flavonoids and total phenolic in the concentrate samples increased with the increase in the volume reduction factor. Volume reduction factor of three showed the best performance of concentration, generating the highest values for lycopene, flavonoid and total phenolic contents. Average permeation flux was 2.3 L h?1 m?2, with continuous extraction of the concentrate at a volumetric reduction ratio of three. Lycopene showed the highest rejection coefficient (0.99), followed by flavonoids (0.96) and total phenolic content (0.65). The hydrophilic antioxidant activity values in both assays were higher than the lipophilic antioxidant activity values. A highly significant correlation was noted between the contents of flavonoids, phenolic compounds, ascorbic acid, and lycopene and their antioxidant potential in both lipophilic and hydrophilic fractions. 相似文献
93.
94.
Alberto Gandini Giovanni Perego Arnaldo Roggero Roberto Vitali Alessandro Zazzetta 《Polymer Bulletin》1984,12(1):71-77
Summary -methylstyrene-butadiene- -methylstyrene linear block copolymers with a pure block structure were prepared by sec-butyllithium and coupling agent in a four-step process. Their morphology is built up of microdomains of poly- -methylstyrene, including the unbonded segments, dispersed in a polybutadiene matrix. Cylindrical domains arranged in a hexagonal lattice or irregularly shaped domains in a disordered phase are observed, depending on the molecular weight of the poly- -methylstyrene segment. 相似文献
95.
We have performed detailed analysis of the fluctuations of the electrical current in electrochemically deposited conductive polymers (CP) using as example polyaniline and poly(3-methylthiophene). These heterogeneous and disordered materials cannot be analyzed in terms of classical conduction mechanisms (like Schottky or Poole-Frenkel emission). Instead, the electrical transport in CPs is to be considered as a stochastic process with large component of noise. We have been able to distinguish several modes of the conduction process in CPs by applying Flicker noise spectroscopy. Thus, we have established that the transport of charge carriers in highly doped CPs is much less correlated than in non-doped ones at the same electric field strength. While applied electric field increases, correlations become lower in a sequence of elementary events contributing to the conductivity of CP. Apparently, the change in the correlation length corresponds to changing mechanism of the electrical conduction. The lower correlation in highly doped sample can be attributed to various factors including change in CP conformation, enhancement in interchain charge transfer and generation of polaron lattice. 相似文献
96.
Brigidi P Swennen E Vitali B Rossi M Matteuzzi D 《International journal of food microbiology》2003,81(3):203-209
Streptococcus thermophilus, Bifidobacterium infantis Y1 and Bifidobacterium breve Y8 strains were identified and enumerated by PCR assay in human fecal samples after intake of the pharmaceutical preparation VSL-3 or yogurt. ThI/ThII primer set, specific for S. thermophilus, was selected testing its specificity against several strains of enterococci, streptococci and other genera colonizing the human intestine. A culture-independent PCR protocol, developed in this study, allowed to directly detect and enumerate S. thermophilus in human feces, excluding culture-based techniques or time consuming DNA isolation and purification procedures. Intestinal persistence of S. thermophilus was studied in feces of 10 healthy subjects given VSL-3 or yogurt. Streptococcal population was detected after 3 days of administration and persisted for 6 days after the treatment suspension. In the same trial, the colonization kinetics of B. infantis Y1 and B. breve Y8 were studied by amplification of colonies with the strain-specific primer sets InfY-BV.L/R and BreY-BV.R/L, showing a host-dependent transient colonization behaviour. PCR analysis of feces from 10 patients affected by inflammatory bowel diseases (IBD) and treated with VSL-3 for 2 months showed a colonization pattern of S. thermophilus, B. infantis Y1 and B. breve Y8 similar to that observed with the healthy subjects. 相似文献
97.
Crack propagation is an important concern in the design of aircraft composite fuselage and wing panels. However, numerical simulation of crack propagation is computationally expensive. This work proposes combining high-fidelity analysis model with low-fidelity model to calculate the crack propagation constraint in the design optimization process. Correction response surfaces are employed to relate the high-fidelity models to the low-fidelity models. Four different forms of correction response surface methods are explored and their prediction capabilities are compared. The multi-fidelity approach is found to be more accurate than single-fidelity response surface method at the same computational cost. 相似文献
98.
A rare case of peritonitis by cecal perforated diverticulum which was diagnosed after surgery by histology is reported. Preoperative diagnosis is often ignored and, in rare cases, is not always clear at laparotomy. Clinical aspects, diagnostic procedures, histological picture and surgical treatment are described. In the literature diverticula are classified as "solitary" and "multiple", "congenital" and "acquired", "true" and "false" and finally "usual type" and "hidden variant". The treatment of cecal acute diverticulitis is, in the majority of patients, surgery. Simple resection of the diverticulum and suture of the breach in double layer is the elective operation of non-complicated diverticulum or with an inflamed projection from the cecal wall ("usual type"). Segmental resection of colon or "right hemicolectomy" is recommended when a precise diagnosis is not possible and in complicated diverticula ("hidden variant"). On the basis of personal experience it is underlined that diagnosis is rarely made preoperatively since the clinical picture suggests an acute appendicitis. If there are some doubts for appendicitis, a incidental tumor or possible perforated diverticulum of the cecum should be considered and urgent surgery is mandatory. 相似文献
99.
100.
Gough Harrison G.; Wenk Ernest A.; Rozynko Vitali V. 《Canadian Metallurgical Quarterly》1965,70(6):432
Parole outcomes for 183 violators and 261 nonviolators (initial sample), and 130 violators and 165 nonviolators (cross-validating sample) were forecast from demographic and personality inventory data. The best single source of prediction in the cross-validating sample was a demographic Base Expectancy index. The best combination was given by an equation including this index, the socialization, selfcontrol, and communality scales of the CPI with positive weightings, and the social presence scale of the CPI with a negative weighting. Conceptual analysis of the equation from the CPI, MMPI, and CPI + MMPI revealed a clear dimension of psychological meaning, having significance for normal as well as for deviant behavior. (44 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献