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91.
92.
Assessments of animal-based outcomes form the core of routine veterinary clinical examinations and are being increasingly used as indicators of animal welfare. A method of group observation that did not require gathering and handling of individual sheep, was used to assess eight animal-based indicators of sheep welfare: demeanour, skin irritation, wool loss, excessive panting, coughing, lameness, and cleanliness of the ventral abdominal and 'breech' (perineum/gluteal/caudal hindlimb) areas. The inter-observer reliability of two or three observers who independently assessed these indicators was tested on 2406 adult sheep and growing lambs across 36 farms and the intra-observer reliability of an experienced, veterinary assessor--the 'test standard observer'--was assessed on 88 adult sheep during four on-farm assessments. Observer reliability was evaluated using Cronbach's alpha (α) comparison of the recorded proportion (%) of sheep affected by each welfare condition and by binomial logistic regression modelling. High levels of inter-observer reliability were identified for the assessment of group lameness (α 0.76-1.00) and cleanliness of the breech area (α 0.97-1.00). Excellent intra-observer reliability was determined for lameness (α 0.99), cleanliness of the breech area (α 0.97), demeanour (α 1.00) and wool loss (α 1.00). In addition, proportion data and logistic regression models identified few between-observer differences. The results suggest that welfare outcomes based on observations of the behaviour and physical appearance of individual animals within a group may offer a reliable and feasible measurement tool for the on-farm assessment of sheep welfare.  相似文献   
93.
Flooding is assumed to cause an energy crisis in plants because-due to a lack of O(2)-mitochondrial respiration is replaced by alcoholic fermentation which yields considerably less energy equivalents. In the present study, the effect of flooding on the carbon metabolism of flooding-tolerant pedunculate oak (Quercus robur L.) and flooding-sensitive European beech (Fagus sylvatica L.) seedlings was characterized. Whereas soluble carbohydrate concentrations dropped in roots of F. sylvatica, they were constant in Q. robur during flooding. At the same time, root alcohol dehydrogenase activities were decreased in beech but not in oak, suggesting substrate limitation of alcoholic fermentation in beech roots. Surprisingly, leaf and phloem sap sugar concentrations increased in both species but to a much higher degree in beech. This finding suggests that the phloem unloading process in flooding-sensitive beech was strongly impaired. It is assumed that root-derived ethanol is transported to the leaves via the transpiration stream. This mechanism is considered an adaptation to flooding because it helps avoid the accumulation of toxic ethanol in the roots and supports the whole plant's carbon metabolism by channelling ethanol into the oxidative metabolism of the leaves. A labelling experiment demonstrated that in the leaves of flooded trees, ethanol metabolism does not differ between flooded beech and oak, indicating that processes in the roots are crucial for the trees' flooding tolerance.  相似文献   
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The present paper studies the existence of asymmetry in the price transmission mechanism between the producer and the consumer prices in the sector of forest products. In particular, the research is focused οn the round wood of long length (> 2 m). For the study of the asymmetry, the Johansen cointegration analysis was used while at the same time two dynamic models were estimated: The Error Correction Model (ECM Model), and the LSE?Henry general to specific model (GETS model). With the assistance of the cointegration technique, we surveyed the existence of a long-run relationship between the producers and the consumers in the Greek round wood market, while the application of the Granger causality test has shown that the consumer price Granger causes the producer price whereas the reverse is not valid. Furthermore, the application of the GETS model confirmed the existence of asymmetry in the price transmission mechanism within the round wood market. Finally, the role of imports in the determination of the producer prices is vital and is confirmed by the findings of the cointegration technique and the Granger causality test.  相似文献   
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ABSTRACT The potential of volatile substances emitted by 'Isabella' grapes (Vitis labrusca) to control gray mold (Botrytis cinerea) on 'Hayward' kiwifruit (Actinidia deliciosa) was studied. The closed Mariotte system was used as a bioassay method to analyze quantitatively the biological action of these volatiles on B. cinerea growth. In vivo experiments compared the effects of volatiles from 'Isabella' grapes versus volatiles from 'Roditis' grapes (V. vinifera) and a B. cinerea control on the growth and disease development of B. cinerea on kiwifruit. The effect of the volatiles on the growth of B. cinerea was tested at various temperatures and times of inoculation after the wounding of kiwifruit, as well as using various weights and developmental stages of the grapes. The 'Isabella' volatiles limited the incidence of infection by reducing both the inoculum density and the activity of the pathogen. The weight and developmental stage of the grapes were important in the degree of inhibitory action of the 'Isabella' volatiles. The inhibitory action was more pronounced at 21 degrees C irrespective of the inoculation time after wounding. The study shows the potential for successful biological control of B. cinerea on kiwifruit by volatiles from 'Isabella' grapes.  相似文献   
98.
Clinical studies have shown that collagen hydrolysate (CH) may be able to protect joints from damage, strengthen joints, and reduce pain from conditions like osteoarthritis. CH is a collection of amino acids and bioactive peptides, which allows for easy absorption into the blood stream and distribution in tissues. However, although various matrices have been studied, the absorption of specific amino acids from CH added to a fresh fermented milk product (FMP) was not studied. The primary objective of the present study was to compare the plasma concentrations of four representative amino acids from the CH (glycine, proline, hydroxyproline, and hydroxylysine) contained in a single administration of a FMP with that of a single administration of an equal amount of neat hydrolyzed collagen. These four amino acids were chosen because they have already been used as markers of CH absorption rate and bioavailability. This was a single-center, randomized open, and crossover study with two periods, which was performed in 15 healthy male subjects. The subjects received randomly and in fasted state a single dose of product 1 (10 g of CH in 100 mL of FMP) and product 2 (10 g of CH dissolved in 100 mL of water) separated by at least 5 days. After administration, the subjects were assessed for plasma concentrations of amino acids and for urine concentrations of hydroxyproline. After FMP administration, mean values of the maximal concentration (Cmax) of the four amino acids were greater than after ingredient administration (p < 0.05). This effect was related to an increased Cmax of proline (p < 0.05). In conclusion, because of their physicochemical characteristics, the fermentation process, and the great homogeneity of the preparation, this milk product improves the plasma concentration of amino acids from CH, that is, proline. The present study suggests an interesting role for FMP containing CH to improve the plasmatic availability of collagen-specific amino acids. Hence, this FMP product could be of potential interest in the management of joint diseases.  相似文献   
99.
100.
The protein kinase HOG1 in high osmolarity glycerol pathway is one of mitogen-activated protein kinases and plays an important role in fungi cellular responses to external stress and stimuli. In this study, AlHOG1, a yeast HOG1 homolog, was isolated from tobacco pathogenic fungus Alternaria longipes and its disrupted mutants were generated using homologous recombination. Compared with the wild-type strain, the mutants grew slower under Minimal-Media, produced less conidia on Potato-Dextrose-Agar and showed a retardation phenotype in conidial germination rate. Colony color observation indicated that AlHOG1 most likely negatively regulated melanin production under nutrients-deficient or osmotic stress. The same action mode of AlHOG1 on hyphal growth in response to certain carbon or nitrogen sources was speculated. Additionally, the disrupted strains were sensitive to osmotic and oxidative stress, and showed increased resistance to dicarboximide, phenylpyrrole and carbendazim fungicides. Meanwhile, results from the comparative analysis between the AlHOG1- and the AlHK1 (encoding a group III histidine kinase)-disrupted mutants showed that AlHOG1 mediated-pathway was partly regulated by the upstream AlHK1 kinase for cellular resistance to salts osmotic stress and that AlHK1 was a primary regulator for cellular sugar and fungicides stress adaptation and likely modulated both AlHOG1-mediated pathway and other unknown mechanisms. Noteworthily, AlHOG1 but not AlHK1 was confirmed to be associated with high concentration glycerol adaptation, which is the first report to our knowledge. Overall, our results indicated that AlHOG1 was involved in multiple physiological processes in A. longipes, including mycelial and conidial development, melanin production, nutrients sensing and multi-stress responses.  相似文献   
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