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141.
The determination of free flavan-3-ol compounds in barley flours (cv. Gotic) and two resulting milling fractions (fine fraction 57% and coarse fraction 43%, w/w) obtained by air classification of dehulled grain is herein described. The determinations were carried out using reversed phase high-performance liquid chromatography coupled with both diode array detection and ESI-MS compared with conventional spectrophotometric determinations (total phenolic compounds by the Folin-Ciocalteu method and free radical scavenging activity with the DPPH assay). Significant correlations among the HPLC quantification, the spectrophotometric data, and the antioxidant capacity of extracts were revealed by Pearson's analysis. Nine flavan-3-ols were identified by HPLC-MS. Catechins and their derivatives were found to make a substantial contribution to the antioxidant power of extracts. The coarse fraction showed larger concentrations of flavan-3-ols (221%) with respect to the fine fraction. This was confirmed by the antioxidant activity of the analyzed flours. The coarse fraction showed the greatest antioxidant activity (1200.1 +/- 66.2 micromol of Trolox equiv/100 g of flour) with respect to whole meal and fine fraction (1025.9 +/- 18.3 and 761.7 +/- 55.3 micromol of Trolox equiv/100 g of flour, respectively).  相似文献   
142.
The ‘road-effect zone’ is a concept developed to describe the impact of road construction on the surrounding area. Although many aspects of the road-effect zone have been investigated, the road-effect zone on soil properties (pH, bulk density, soil moisture, electrical conductivity, organic matter (%), C (%), total N (%), available Na, Ca, Mg, P, and K), light regimes (leaf area index and canopy cover), and a Raunkiaer’s life-form classification of plants remains poorly understood, especially in oriental beech (Fagus orientalis Lipsky) forests. Hence, the main aims of this research were to estimate the extent of the road-effect zone and to identify the main environmental changes due to forest roads. Specifically, we aimed to evaluate road-effects on: (1) the composition of herbaceous species and tree regeneration (up to 100 m distance from the forest road); (2) the light regime; and (3) soil properties, potentially related to changes in ecosystem functions and composition. We observed that forest roads can have significant impacts on soil, stand characteristics, and vegetation composition. The estimated road-effect zone extended up to 30 m from the road edge. Landscape planners should be aware that road-effect zones can potentially influence the ecology and environmental conditions of an area up to 30 m from the road edge.  相似文献   
143.

Objective

To assess the effects of xylazine and dexmedetomidine on equine chondrocytes, in vitro.

Study design

Prospective, experimental study.

Study material

Equine articular chondrocytes from five male horses.

Methods

Chondrocytes were isolated from healthy equine articular cartilage of the metacarpo/metatarsophalangeal joints. Cell viability was assessed using the WST-8 assay by exposing chondrocytes to xylazine (0.5, 1, 2, 4, 8, 16.6, 25, 50 mg mL?1) or dexmedetomidine (0.001, 0.005, 0.01, 0.05, 0.175, 0.25 mg mL?1) for 15, 30 and 60 minutes. Based on the results of these tests, cells were treated with xylazine (1, 4, 25 mg mL?1) or dexmedetomidine (0.05, 0.175, 0.25 mg mL?1) for 15 minutes to further evaluate: cell viability by neutral red uptake; cell membrane integrity by lactate dehydrogenase release and by fluorescence microscopy with Hoechst 33342 and propidium iodide (PI), and apoptosis by flow cytometry using double staining with annexin V-fluorescein isothiocyanate/PI and by cell morphology.

Results

Both drugs reduced cell viability in a dose-dependent manner. Specifically, all xylazine concentrations, except 0.5 mg mL?1 and 1 mg mL?1, significantly reduced cell viability, whereas the effects of dexmedetomidine were evident only at 0.175 mg mL?1 and 0.25 mg mL?1. The highest concentrations of xylazine (25 mg mL?1) and dexmedetomidine (0.25 mg mL?1) caused loss of membrane integrity. Cell morphology and flow cytometry analyses demonstrated signs of late apoptosis in xylazine-treated cells, and signs of late apoptosis and necrosis in dexmedetomidine-treated cells.

Conclusions and clinical relevance

This study offers new insights into the potential chondrotoxicity induced by dexmedetomidine and xylazine. Therefore, the intra-articular administration of α2-agonists should be conducted with care, especially for doses of ≥ 4 mg mL?1 of xylazine and 0.175 mg mL?1 and 0.25 mg mL?1 of dexmedetomidine.  相似文献   
144.
Reviews of the current statuses of forests and the impacts of climate change on forests exist at the (sub)continental scale, but rarely at country and regional levels, meaning that information on causal factors, their impacts, and specific regional properties is often inconsistent and lacking in depth. Here, we present the current status of forest production and biogeochemistry and the expected impacts of climate change on them for Belgium. This work represents a case study for the temperate oceanic zone, the most important bioclimatic zone in northwestern Europe. Results show that Belgian forests are mainly young, very productive, and have a high C-sequestration capacity. Major negative anomalies in tree vitality were observed in the 1990s and—as result of disturbances—in the last decade for sensitive species as poplars and European beech. The most severe disturbances were caused by extreme climatic events, directly (e.g. storms) or indirectly (e.g. insect outbreaks after a mild autumn with an early/severe frost). Because of atmospheric deposition and soil fertilization (due to the previous use of the land), nutrient stocks of Belgian forests are likely to sustain the future enhancement in productivity which is expected to follow the increase in atmospheric CO2 concentration that will occur in years to come. However, in the long term, such (enhanced) forest production is likely to be limited by nutrient deficiencies at poor sites and by drought for sensitive species such as beech and (particularly) Norway spruce. Drought conditions will likely increase in the future, but adverse effects are expected on a relatively limited number of tree species. The potential impacts of windstorms, insects and fungi should be carefully investigated, whereas fires are less of a concern.  相似文献   
145.
Scots pine (Pinus sylvestris L.) forests of many inner Alpine valleys have recently displayed a quick loss of vitality. A decline disease has been suggested as the cause, with drought as the main predisposing factor and the additional contribution of biotic agents inciting tree dieback. This study is focused on Valle d’Aosta, a dry, inner-Alpine region in NW Italy. We inferred vitality changes between years 2000 and 2007 by computing reductions in enhanced vegetation index (EVI). Image differencing was carried out on pre-processed Moderate Resolution Imaging Spectroradiometer (MODIS) imagery taken in late springtime and validated against ancillary ground truth. We: (1) tested whether EVI reductions in Scots pine forests were significantly higher than those of a control species and of a wetter region for the same species, (2) analyzed decline incidence as a function of site and topographic variables, and (3) assessed the relative influence of site and stand structure on decline probability by means of path analysis. Mean EVI in the study area increased due to an early onset of the 2007 growing season. Nevertheless, the incidence of decline was 6.3% and significantly greater for Scots pine than the control species and site. Low-elevation, northerly exposed sites exhibited the highest incidence of decline. Path analysis suggested that the most important determinants of decline probability were slope, solar radiation, and stand sparseness.  相似文献   
146.
This report describes multiple endocrine neoplasia in a dog, which is a rare hereditary disorder characterized by the presence of two or more neoplasms of different endocrine tissues within a patient. A 14 yr old dog was evaluated for polyuria/polydipsia, polyphagia, and abdominal enlargement. Adrenal-dependent hyperadrenocorticism with concomitant left thyroid enlargement and a presumed abdominal metastatic lesion were diagnosed by an adrenocorticotropic hormone stimulation test, ultrasonography, and computed tomography. Trilostane therapy was initiated and resolved the clinical signs for 2 yr at which time the dog presented with left testicular enlargement. The dog was euthanized and was diagnosed with adrenocortical carcinoma, thyroid carcinoma, an abdominal mass compatible with a metastatic lymph node, and bilateral interstitial cell testicular adenomas. To the authors' knowledge, this is the first report to describe the concomitant association of these types of endocrine neoplasms in a dog. The concomitant presence of these neoplasms could represent a potential variant of multiple endocrine neoplasia; however, the presence of the interstitial cell testicular adenomas may have only been an incidental finding. If any of these tumors are diagnosed, veterinarians should perform a thorough clinical assessment to evaluate for the presence of additional endocrine neoplasms or hyperplasia.  相似文献   
147.
148.

BACKGROUND

Chemical products against fungi and oomycetes pose serious environmental issues. In the last decade, the use of less impacting active ingredients was encouraged to reduce chemical inputs in viticulture. In this study, the effect of different antifungal compounds on grapevine agronomic, physiological, and molecular responses in the vineyard was evaluated in addition to protection against powdery and downy mildews.

RESULTS

In 2 years and in two Vitis vinifera cultivars (Nebbiolo and Arneis), a conventional crop protection approach, based on traditional fungicides (sulfur and copper), was compared to combined strategies. A well-known resistance inducer (potassium phosphonate), Bacillus pumilus strain QST 2808 and calcium oxide, both active ingredients whose biological interaction with grapevine is poorly characterized, were applied in the combined strategies in association with chemical fungicides. Despite a genotype effect occurred, all treatments optimally controlled powdery and downy mildews, with minimal variations in physiological and molecular responses. Gas exchange, chlorophyll content and photosystem II efficiency increased in treated plants at the end of season, along with a slight improvement in the agronomic performances, and an activation of molecular defense processes linked to stilbene and jasmonate pathways.

CONCLUSION

The disease control strategies based on potassium phosphonate, Bacillus pumilus strain QST 2808 or calcium oxide combined with traditional chemical compounds did not cause severe limitations in plant ecophysiology, grape quality, and productive yields. The combination of potassium phosphonate and calcium oxide with traditional fungicides can represent a valuable strategy for reducing copper and sulfur inputs in the vineyards, including those organically managed. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
149.
This review summarises the literature on the biological control of Anoplophora spp. (Coleoptera: Cerambycidae) and discusses its potential for use in Europe. Entomopathogenic fungi: Beauveria brongniartii Petch (Hypocreales: Cordycipitaceae) has already been developed into a commercial product in Japan, and fungal infection results in high mortality rates. Parasitic nematodes: Steinernema feltiae Filipjev (Rhabditida: Steinernematidae) and Steinernema carpocapsae Weiser have potential for use as biopesticides as an alternative to chemical treatments. Parasitoids: a parasitoid of Anoplophora chinensis Forster, Aprostocetus anoplophorae Delvare (Hymenoptera: Eulophidae), was discovered in Italy in 2002 and has been shown to be capable of parasitising up to 72% of A. chinensis eggs; some native European parasitoid species (e.g. Spathius erythrocephalus) also have potential to be used as biological control agents. Predators: two woodpecker (Piciformis: Picidae) species that are native to Europe, Dendrocopos major Beicki and Picus canus Gmelin, have been shown to be effective at controlling Anoplophora glabripennis Motschulsky in Chinese forests. The removal and destruction of infested and potentially infested trees is the main eradication strategy for Anoplophora spp. in Europe, but biological control agents could be used in the future to complement other management strategies, especially in locations where eradication is no longer possible. © 2014 Crown copyright. Pest Management Science © 2014 Society of Chemical Industry  相似文献   
150.
The possibility of using near-infrared spectroscopy (NIRS) for the authentication of wild European sea bass ( Dicentrarchus labrax ) was investigated in this study. Three different chemometric techniques to process the NIR spectra were developed, and their ability to discriminate between wild and farmed sea bass samples was evaluated. One approach used spectral information to directly build the discrimination model in a latent variable space; the second approach first used wavelets to transform the spectral information and subsequently derived the discrimination model using the transformed spectra; in the third approach a cascaded arrangement was proposed whereby very limited chemical information was first estimated from spectra using a regression model, and this estimated information was then used to build the discrimination model in a latent variable space. All techniques showed that NIRS can be used to reliably discriminate between wild and farmed sea bass, achieving the same classification performance as classification methods that use chemical properties and morphometric traits. However, compared to methods based on chemical analysis, NIRS-based classification methods do not require reagents and are simpler, faster, more economical, and environmentally safer. All proposed techniques indicated that the most predictive spectral regions were those related to the absorbance of groups CH, CH(2), CH(3), and H(2)O, which are related to fat, fatty acids, and water content.  相似文献   
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