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21.
Besides the health benefits associated with whole-grain consumption, cereals are recognized sources of health-enhancing bioactive components such as carotenoids, which are a group of yellow pigments involved in the prevention of many degenerative diseases and which have been used for a long time as indicators of the color quality of durum wheat and pasta products. This work reports a fast, sensitive, and selective procedure for the extraction and determination of carotenoids from cereals and cereal byproducts. The method involves sample saponification and extraction followed by normal-phase high-performance liquid chromatography, allowing the separation of the main carotenoids pigments of cereals, especially lutein and zeaxanthin. An application of the established method to various species of cereals and cereal byproducts is also shown. The highest carotenoid levels were found in maize (approximately 11.14 mg/kg of dry weight), which contains high amounts of beta-cryptoxanthin (2.40 mg/kg of dry weight), and, among the cereals considered, has the highest content of zeaxanthin (6.43 mg/kg of dry weight) and alpha+beta-carotene (1.44 mg/kg of dry weight). With the exception of maize, lutein is the main compound found (from 0.23 to 2.65 mg/kg of dry weight in oat and durum wheat, respectively). Moreover, whereas alpha+beta-carotene and zeaxanthin are principally localized in the germ, lutein is equally distributed along the kernel.  相似文献   
22.
A 6 yr old pregnant Yorkshire terrier bitch presented 62 days after mating with an acute history of vomiting and coughing. The owners also reported that the dog was polyuric and polydypsic for the last 2 weeks. Complete blood count, serum biochemistry, and urinalysis revealed hyperglycemia, ketonemia, ketonuria, and metabolic acidosis. Diabetic ketoacidosis was diagnosed and after emergency treatment, including fluid therapy, prophylactic antibiotics, and regular insulin, the bitch whelped six healthy normal puppies. Two weeks after treatment, the bitch was clinically normal with normal fructosamine levels. To the authors' knowledge, this is the first reported case of gestational diabetes mellitus in a small breed dog.  相似文献   
23.
Human rotaviruses, discovered nearly 20 years ago, have been proven to be major cause of paediatric diarrhoeal disease morbidity and mortality. The clinical significance of these viruses stimulated basic studies on their biology, molecular and antigenic properties and epidemiology. General features, clinical relevance, epidemiologic pattern and laboratory diagnosis of human rotavirus infections are here reviewed.  相似文献   
24.
Summary Karyomorphological similarities among four species of the genusVigna, V. unguiculata, V. luteola, V. oblongifolia andV. vexillata, were evaluated. Two different approaches were followed: cytomorphometrical determinations, carried out with an automated image analysis system to improve resolution, yielded some karyotypical indices; the distribution of heterochromatin bands was interpreted using a recently reported algorithm. Both methods led to similar results: the most karyologically similar species toV. unguiculata appears to beV. luteola, whileV. oblongifolia appears to be the least related one.  相似文献   
25.
Grapevine virus A (GVA) is considered one of the viruses associated with rugose wood (RW), one of the most economically important diseases of grapevine. Thirty-seven GVA isolates collected from grapevine cultivars from Marche (central-eastern Italy), Apulia and Campania (southern Italy), were subjected to molecular characterization. The genetic and population diversity was studied in the coat protein (CP) gene by RT-PCR-RFLP analysis with three restriction enzymes (MseI, AluI, and AciI), and nucleotide sequencing. A new primer pair (CP1F/R) allowing amplification of the whole CP gene (621 bp) was developed. RFLP with AciI yielded the highest number of variants in GVA isolates, showing seven different ‘simple’ profiles (A, B, C, D, E, F, and G). ‘Complex’ profiles were also found, and the most common variant combination was A + B in 39% of isolates. The analysis of GVA sequences confirmed the presence of plants infected with more than one GVA variant and suggested that RT-PCR-RFLP is suitable for evaluating population diversity of GVA enabling a screening of different haplotypes. The distribution of RFLP profiles and the phylogenetic analysis were not correlated with the location of infected plants, showing the presence of a GVA population with genetic diversity in the average with those of RNA viruses.  相似文献   
26.
27.
The kinetics of crystallization of high-melting fraction (HMF) and a mixture of 40% HMF and 60% low-melting fraction (LMF) of milk fat were studied at 5 degrees C by time-resolved in-situ synchrotron X-ray diffraction. HMF crystallized in the alpha polymorph, had a longer lifetime than the ones previously reported in pure milk fat, and was almost completely solid. The HMF/LMF mixture crystallized initially in the alpha form and transformed into the beta' polymorph, with a solid fat content much lower than that of HMF. The polymorphic change was therefore attributed to a delayed sudden formation of beta' mixed crystals from the uncrystallized melt. These findings are important for the food industry and as fundamental knowledge to improve our understanding of the origin of the macroscopic physical properties of solid milk fat fractions used in many manufacturing processes.  相似文献   
28.
This review presents an overview of the potential use of substrate‐borne vibrations for the purpose of achieving insect pest control in the context of integrated pest management. Although the importance of mechanical vibrations in the life of insects has been fairly well established, the effect of substrate‐borne vibrations has historically been understudied, in contrast to sound sensu stricto. Consequently, the idea of using substrate‐borne vibrations for pest control is still in its infancy. This review therefore focuses on the theoretical background, using it to highlight potential applications in a field environment, and lists the few preliminary studies that have been or are being performed. Conceptual similarities to the use of sound, as well as limitations inherent in this approach, are also noted. © 2014 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
29.
The present study introduces an exploratory data analysis based on structural indicators with the aim to assess the effect of silvicultural practices on tree stand structure. The study was carried out in three Italian beech forests of different ages with stand structures that originated from dissimilar regeneration and cultivation techniques(Cansiglio, northern Italy, Chiarano, central Italy,and Mongiana, southern Italy). Ten structural indicators were considered when investigating the latent multivariate relationship between stand structure attributes before and after thinning operations by using a multiway factor analysis(MFA). The MFA results identified the older stand at Cansiglio as more homogeneous for cultivation regimes,and more stable to practices when compared with the younger sites(Chiarano and Mongiana). Heterogeneous stands were sensitive to silvicultural practice thus suggesting their possible impact on forest attributes. The proposed approach proved to be an operational tool to evaluate comprehensively the response of forest structure to planned interventions.  相似文献   
30.
We estimated water-use efficiency and potential photosynthetic assimilation of Holm oak(Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in two Mediterranean coppice forests. We used standard techniques for quantifying gas exchange and carbon isotopes in leaves and analyzed total chlorophyll, carotenoids and nitrogen in leaves collected from Mediterranean forests managed under the coppice system. We postulated that responses to drought of coppiced trees would lead to differential responses in physiological traits and that these traits could be used by foresters to adapt to predicted warming and drying in the Mediterranean area. We observed physiological responses of the coppiced trees that suggested acclimation in photosynthetic potential and water-use efficiency:(1) a significant reduction in stomatal conductance(p0.01) wasrecorded as the drought increased at the SW site;(2) foliar δ13C increased as drought increased at the SW site(p0.01);(3) variations in levels of carotenoids and foliar nitrogen, and differences in foliar morphology were recorded, and were tentatively attributed to variation in photosynthetic assimilation between sites. These findings increase knowledge of the capacity for acclimation of managed forests in the Mediterranean region of Europe.  相似文献   
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