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61.
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Federico BrilliLukas Hörtnagl Albin Hammerle Alois HaslwanterArmin Hansel Francesco LoretoGeorg Wohlfahrt 《Agricultural and Forest Meteorology》2011,151(12):1731-1740
Climate change is expected to affect the Alps by increasing the frequency and intensity of summer drought events with negative impacts on ecosystem water resources. The response of CO2 and H2O exchange of a mountain grassland to natural fluctuations of soil water content was evaluated during 2001-2009. In addition, the physiological performance of individual mountain forb and graminoid plant species under progressive soil water shortage was explored in a laboratory drought experiment. During the 9-year study period the natural occurrence of moderately to extremely dry periods did not lead to substantial reductions in net ecosystem CO2 exchange and evapotranspiration. Laboratory drought experiments confirmed that all the surveyed grassland plant species were insensitive to progressive soil drying until very low soil water contents (<0.01 m3 m−3) were reached after several days of drought. In field conditions, such a low threshold was never reached. Re-watering after a short-term drought event (5 ± 1 days) resulted in a fast and complete recovery of the leaf CO2 and H2O gas exchange of the investigated plant species. We conclude that the present-day frequency and intensity of dry periods does not substantially affect the functioning of the investigated grassland ecosystem. During dry periods the observed “water spending” strategy employed by the investigated mountain grassland species is expected to provide a cooling feedback on climate warming, but may have negative consequences for down-stream water users. 相似文献
63.
Lante A Nardi T Zocca F Giacomini A Corich V 《Journal of agricultural and food chemistry》2011,59(10):5318-5324
The search for renewable and abundant sources of antioxidants has recently focused on agricultural byproducts, especially promising due to their natural origins and low costs. In particular, plant raw materials are sources of important compounds such as dietary fiber, carotenoids, tocopherols, and polyphenolics, which are mostly discarded during harvesting and processing. Among these vegetal crops, red chicory is attractive because of the large quantity of its byproducts (residues as leaves and stems); moreover, there is no information on its role as a food and feed ingredient. In this study, red chicory leaf residue was evaluated as a natural substitute for synthetic antioxidants for the food and feed industry. After lyophilization, a red chicory extract (RC) was characterized for its phenolic profile and its oxidative stability as compared to BHT. RC was shown to reduce lipid peroxidation of different oils in the Rancimat test. In addition, the antioxidant property of RC was studied in a model system by evaluating the Saccharomyces cerevisiae response to oxidative stress by means of gene expression. In this analysis, the RC extract, added to the yeast culture prior to oxidative stress induction, exhibited a pleiotropic protective effect on stress responsive genes. 相似文献
64.
Bellato S Del Frate V Redaelli R Sgrulletta D Bucci R Magrì AD Marini F 《Journal of agricultural and food chemistry》2011,59(9):4349-4360
A rapid accurate and precise method for simultaneous determination of β-glucan and protein content in naked oat samples, based on the coupling of near-infrared spectroscopy and chemometrics, is presented. In particular, three different spectroscopic approaches [near infrared reflectance (NIR) and transmittance (NIT) on flour and NIT on whole grains] and various spectral pretreatments were considered. To account for the possibility of outlying samples, a robust version of the PLS algorithm (namely partial robust M-regression) was used. All the models resulted as accurate as the reference methods, reflectance spectroscopy being the technique providing the best outcomes. Variable reduction by inclusion of the most relevant predictors only (as evaluated by VIP scores) resulted in simpler and, in one case, more parsimonious models, without loss in accuracy. 相似文献
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Federico Tinivella Lucia M. Hirata Mikael A. Celan Sandra A. I. Wright Tahsein Amein Annegret Schmitt Eckhard Koch Jan M. van der Wolf Steven P. C. Groot Dietrich Stephan Angelo Garibaldi Maria Lodovica Gullino 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):139-151
Greenhouse trials were carried out in order to test the efficacy of different seed treatments as alternatives to chemicals
against Colletotrichum lindemuthianum cause of anthracnose on bean and Ascochyta spp. cause of Ascochyta blights on pea, respectively. Resistance inducers, commercially formulated microorganisms, non-formulated
selected strains of different microorganisms (fungi, bacteria and yeasts) and plant extracts were applied as dry or liquid
seed treatments on naturally infested seeds. Seedling emergence and disease incidence and/or severity were recorded. Almost
all seed treatments turned out to be ineffective in controlling the Ascochyta infections, which is in line with the literature
stating that these pathogens are difficult to control. The only alternative treatments that gave some control of Ascochyta spp. were thyme oil and a strain of Clonostachys rosea. The resistance inducers tested successfully controlled infections of bean by C. lindemuthianum. Among the formulated microorganisms, Bacillus subtilis-based formulations provided the best protection from anthracnose. Some strains of Pseudomonas putida, a disease-suppressive, saprophytic strain of Fusarium oxysporum and the mustard powder-based product Tillecur also proved to be effective against bean anthracnose. However, among the resistance
inducers as well as among the other groups, certain agents caused a significant reduction of plant emergence. Different alternative
seed treatments can therefore be used for the control of C. lindemuthianum on bean, while on pea only thyme oil and a strain of Clonostachys rosea showed some effectiveness against Ascochyta spp. 相似文献
68.
An adenocarcinoma of the disseminated prostate gland with pulmonary, myocardial and renal metastases is described in a 12-year-old, neutered male European cat. Histologically, the tumour was localised in the spongy layer of the prostatic urethra and showed an epithelial alveolar pattern. Considering the anatomic, microscopic and immunohistochemical findings, the tumour was diagnosed as an adenocarcinoma of the disseminated prostate gland. To our knowledge this is the first report of adenocarcinoma of the disseminated prostate gland in a cat. 相似文献
69.
Liliana Mutascio Federico Vilaplana Grosso Jos Ramos‐Vara Micha Simons 《Veterinary radiology & ultrasound》2019,60(2):E10-E14
A 10‐month‐old German Shepherd Dog presented for evaluation of intermittent vomiting. Abdominal radiographs revealed a marked right cranial mass effect. Initial differentials included abscess/cyst or less likely neoplasia from undetermined origin. On abdominal ultrasound the mass appeared cystic and thin walled. Computed tomography revealed a large cystic lesion originating from the pyloroduodenal junction causing pyloric outflow obstruction. A noncommunicating duodenal duplication cyst was found on exploratory laparotomy and further confirmed with histopathology and immunohistochemistry. Enteric duplication cyst should be considered as a differential in young dogs with gastrointestinal signs and a cystic abdominal mass detected with different imaging modalities. 相似文献
70.
Hilda A. Sánchez-de-Jesús Víctor Arroyo-Rodríguez Ellen Andresen Federico Escobar 《Landscape Ecology》2016,31(4):843-854