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161.
An instrumental texture analysis method has been optimized for the differentiation of grape ripening stages based on the simultaneous determination of mechanical and acoustic parameters of the seeds. Two factorial central composite design was used to optimize the most influencing operative conditions (speed and deformation) on mechanical and acoustic measurements. This experimental design in combination with response surface methodology showed that the most responsive parameters to changes in seeds during ripening were Young's modulus of elasticity, many acoustic parameters measured with instrumental gain set to 0 (acoustic energy, linear distance, and number of peaks) and others measured at 24 dB gain (linear distance, number of peaks, and average pressure level). However, the optimal operative conditions depended on the texture parameter used. A correlation study between texture parameters and phenolic compounds of the seeds revealed that acoustic parameters like the average pressure level could be proposed as phenolic maturity indices.  相似文献   
162.
A four-year study was conducted on young Olea europaea L. trees to investigate the effect of deficit irrigation starting from the onset of fruit production. Subsurface drip irrigation was used to supply 100% (FI), 46–52% (DI), or 2–6% (SI) of tree water needs. Tree growth was reduced by deficit irrigation, whereas, return bloom was not. Per tree fruit yield of DI trees was 68% that of FI, but fruit yield efficiency based on tree size was similar between treatments. Fruit set and the number of fruits of FI trees were similar to those of DI trees and significantly higher than in SI trees. No significant differences in fruit fresh weight were found between FI and DI. The oil yield and oil yield efficiency of the DI treatment were 82 and 110% that of FI trees, respectively. A level of about 50% deficit proved sustainable to irrigate trees for oil production.  相似文献   
163.

Background  

In domestic animals many biochemical and physiological processes exhibit daily rhythmicity. The aim of the present study was to investigate the rhythmic pattern of salivary and serum urea concentrations in sheep.  相似文献   
164.
Beta-galactosidase and peroxidase are enzymes reported to have roles in pepper maturation. Fertilizer rate may affect activity of these enzymes in fruit maturing on the plant. Nine pepper cultivars, five non-pungent and four pungent, were fertilized at two rates in field plots in 1997 and 1998 at Lane, OK, USA. Fruit were harvested at mature green, turning, and red color developmental stages, and assayed for beta-galactosidase and peroxidase activity. Overall fruit beta-galactosidase activity increased as fertilizer rate increased, and was highest in red fruit. Fertilizer rate and fruit developmental stage did not affect peroxidase activity in 1997, but peroxidase activity was highest in red fruit in 1998. Enzyme activity appeared to be cultivar dependent, and patterns differed in both years. Activities of both enzymes were higher at the red stage in many of the non-pungent peppers than in pungent peppers. These data suggest that increased fertilizer affects the activity of at least one enzyme in fruit maturing on the plant. Cultural practices affecting enzyme activity may be used to modify concentrations of components in plants that are important for human consumption.  相似文献   
165.
The globe artichoke is a widely consumed vegetable in the Mediterranean Basin, with Italy being the leading producer. In southern Italy, its cultivation contributes to local economic stability and social development. The producers are increasingly choosing to replace autochthonous varieties, such as ‘Violetto di Sicilia’, with cultivars bred or selected outside of the region, putting pressure on the maintenance of traditional varieties. Here, we have undertaken a detailed morphological and chemical analysis of a group of clones selected from a population of ‘Violetto di Sicilia’. All the traits measured displayed genetic variation, particularly the total content of phenolics and minerals. The capitula of the ‘Violetto di Sicilia’ clones contained, on average, 6.3 g kg−1 of fresh weight total phenolics, compared with 4.5 g kg−1 in the two commercial varieties. The clones also had more inulin than commercial varieties (254 vs. 225 g kg−1 of dry matter), as well as a good mineral content. The set of clones is of interest in the context of the proposed improvement of the crop through breeding and selection of genotypes with high nutritional quality and a specific end-use (industrial processing or fresh consumption).  相似文献   
166.
The first epidemiological survey of Border disease virus (BDV) was undertaken in small ruminants in Japan. Ovine sera, collected from the northern prefectures of Hokkaido, Aomori and Iwate, were examined for the presence of antibodies against BDV using the neutralization peroxidase-linked antibody test. Twenty-nine (17.6%) of one hundred and sixty-five samples were seropositive for BDV. Results were specific, excluding cross-reactions with bovine viral diarrhea virus (BVDV). Only one sample (0.6%) was positive for BVDV, and was negative for BDV. Despite serological evidence of virus circulation, there have been no clinical cases of border disease in sheep in Japan. Although no diagnostic measures were performed, the infection did not appear to be associated with a reduction in ewe fertility nor with lamb mortality.  相似文献   
167.
Zinc deficiency causes skin diseases both in humans and in animals. The underlying pathogenic mechanisms remain unclear, but a growing body of evidence indicates a role for zinc in skin protection against free radical‐induced oxidative damage. The immunohistochemical expression of heat shock proteins (HSPs; Hsp27, Hsp72, Hsp73 and Hsp90), Cu/Zn superoxide dismutase (SOD), metallothionein (MT), Ki‐67 antigen and active caspase‐3 were evaluated in normal canine skin and in samples from eight dogs with zinc‐responsive dermatosis. All investigated HSPs showed intense cytoplasmic immunostaining in the affected epidermis. Focal nuclear positivity of Hsp72 was also detected in keratinocytes. Although Cu/Zn SOD expression was similar to that observed in normal skin, MT immunoreactivity occurred in both the cytoplasm and the nucleus of basal cells in normal skin but was absent from the affected epidermis. Caspase‐3 activation was also absent in the involved epidermis, which revealed a high Ki‐67 index (a 3.5‐ to 9‐fold increase compared with normal skin). These results support the hypothesis that cellular response to stress, particularly oxidative stress, is involved in the pathogenesis of skin lesions in canine zinc‐responsive dermatosis. The lack of MT immunoreactivity in the affected epidermis may be indicative of low zinc levels, thus resulting in vulnerability to oxidative damage. In contrast, high expression levels of HSPs in skin during zinc deficiency may confer protection against a variety of dangerous stimuli, contributing to inhibition of apoptosis and to cell cycle regulation of proliferating keratinocytes.  相似文献   
168.
Vascular perfusion was assessed in 10 dogs without prostatic abnormalities and 26 dogs with prostatic disease using contrast‐enhanced ultrasound. The time to reach peak contrast intensity (TTP) and peak perfusion intensity (PPI) were measured, and histological biopsies were collected from each dog. Biopsies confirmed normal prostate (n = 10), benign prostatic hyperplasia (n = 11), mixed benign pathology (n = 9), prostatitis (n = 1), prostatic malignancy [adenocarcinoma (n = 4); leiomyosarcoma (n = 1)]. In normal dogs, mean PPI was 16.8% ± 5.8 SD, and mean TTP was 33.6 ± 6.4 s. Benign conditions overall were not statistically different from normal dogs (p > 0.05); for benign prostatic hyperplasia, mean PPI was 16.9 ± 3.8%, and mean TTP was 26.2 ± 5.8 s; for mixed benign pathology mean PPI was 14.8 ± 7.8%, and mean TTP was 31.9 ± 9.7 s; for prostatitis, PPI was 14.2%, and TTP was 25.9 s. The malignant conditions overall had perfusion values that differed from the normal dogs (p < 0.05), although evaluation of the data for individual malignancies did not demonstrate a consistent trend; for adenocarcinomas, the PPI was numerically higher with a mean of 23.7 ± 1.9%, and the mean TTP was 26.9 ± 4.8 s, whilst for the dog with leiomyosarcoma values were numerically lower with a PPI of 14.1% and TTP of 41.3 s. Contrast‐enhanced ultrasound appears to offer some ability to document differences in perfusion that may differentiate between malignant and benign lesions, although studies with larger numbers of animals are required to confirm this contention.  相似文献   
169.
When changing from spatially random to spatially connected appearances as conditions become wetter in their seasonal time dynamics, soil moisture spatial patterns show a behaviour similar to phase transition processes. In a previous work, once implemented an ad-hoc methodology, we have demonstrated that such a phase change shows critical point behaviour. Moreover, the value of the critical probability seems to be an intrinsic characteristic of a catchment, being insensitive to renormalization (rescaling), as well as to model parameterization.  相似文献   
170.
A common seagull (Larus fuscus) was found near the southern coast of Italy by the veterinarians of the local wild animal rescue center. Physical examination of the bird revealed an ulcerated mass involving a majority of the oral cavity; the mass did not allow for normal feeding. After the bird died necropsy was performed and the mass was histologically and immunohistochemically examined. The morphology and the immunoreactivity for Melan-A and S-100 antigens led to a diagnosis of malignant melanoma. This is the first case of malignant melanoma described in a seagull, and herein we compare the characteristics of the present case with malignant melanoma already described in domestic animals.  相似文献   
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