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71.
Gas dispersion in a set of three different porous materials with similar particle size, as a function of material tortuosity and anisotropy ratio, was investigated. The materials were packed with different spatial orientations of the individual particles so as to create media with different tortuosity and anisotropy ratios. Three different media (slate chips, wood chips, and pebbles) and four particle orientations have been used to generate a total of nine different porous media mimicking single porosity, dual porosity isotropic, anisotropic, aggregated, or granular materials. Resulting values of tortuosity and anisotropy ratio for each medium were determined via measurements of gas permeability and molecular gas diffusion coefficient. These values were then compared to measured values of gas dispersivity for each medium. The results showed that dispersivity is inversely proportional to tortuosity but directly proportional to anisotropy ratio and that the relations were approximately linear within the range of tortuosities and anisotropy ratios investigated. Wood chips (dual porosity material) yielded higher values of gas dispersivity compared to slate chips (single porosity material). A likely reason is in part the difference in pore structure between the materials and in part a difference in particle surface roughness (which was highest for wood chips) both of which affects dispersion.  相似文献   
72.
Celiac disease is a food intolerance triggered by the ingestion of gluten-containing cereals; the only therapy is a strict gluten-free diet for life. In recent years, amaranth flour has received considerable attention as an interesting source for the formulation of gluten-free products due to its high nutritional value and low content of prolamins, the toxic proteins for celiacs. The aim of this study was to characterize 40 amaranth varieties using both SDS-PAGE/immunoblotting and ELISA to assess their possible tolerance by celiac subjects. All of the amaranth samples studied showed similar binding affinities for both specific anti-gliadin antibodies and human IgAs. In most amaranth grains, the content of gluten-like proteins measured by ELISA was <20 ppm. The molecular characterization of amaranth proteins suggests that amaranth is safe for celiacs to consume. It is recommended that the most suitable amaranth varieties are those having the lowest content of proteins cross-reacting with anti-gliadin antibodies.  相似文献   
73.
Rabbit hemorrhagic disease virus (RHDV) is the etiological agent of a lethal and contagious disease of rabbits that remains as a serious problem worldwide. As this virus does not replicate in cell culture systems, the capsid protein gene has been expressed in heterologous hosts or inserted in replication-competent viruses in order to obtain non-conventional RHDV vaccines. However, due to technological or safety issues, current RHDV vaccines are still prepared from organs of infected rabbits. In this work, two human type 5 derived replication-defective adenoviruses encoding the rabbit hemorrhagic disease virus VP60 capsid protein were constructed. The recombinant protein was expressed as a multimer in mouse and rabbit cell lines at levels that ranged from approximately 120 to 160 mg/L of culture. Mice intravenously or subcutaneously inoculated with a single 10(8) gene transfer units (GTU) dose of the AdVP60 vector (designed for VP60 intracellular expression) seroconverted at days 7 and 14 post-immunization, respectively. This vector generated a stronger response than that obtained with a second vector (AdVP60sec) designed for VP60 secretion. Rabbits were then immunized by parenteral or mucosal routes with a single 10(9)GTU dose of the AdVP60 and the antibody response was evaluated using a competition ELISA specific for RHDV or RHDVa. Protective hemagglutination inhibition (HI) titers were also promptly detected and IgG antibodies corresponding with inhibition percentages over 85% persisted up to one year in all rabbits, independently of the immunization route employed. These levels were similar to those elicited with inactivated RHDV or with VP60 obtained from yeast or insect cells. IgA specific antibodies were only found in saliva of rabbits immunized by intranasal instillation. The feasibility of VP60 production and vaccination of rabbits with replication-defective adenoviral vectors was demonstrated.  相似文献   
74.
In Italy, the first human case of West Nile Virus (WNV) infection was reported in 2008 and, since then, the number of cases has been steadily increasing. In this study, we describe the temporal and spatial pattern of WNV infection risk among humans in Italy, focusing on the human cases of West Nile Neuro‐invasive Disease (WNND) observed between 2008 and 2017. Incidence rates are estimated for each year and province under study. The incidence temporal trend is estimated using Poisson regression, and a spatio‐temporal cluster detection analysis is performed to detect high‐risk areas. In total, 231 WNND cases were notified in Italy between 2008 and 2017. The annual incidence rates increased during the study period (annual percentage change: 11.7%; 95%CI: ?0.9%; 26.1%). A geographical spread of the disease was observed during the study period throughout Northern Italy, with an increasing number of affected provinces. Provinces close to the Po River (the main river in the north of Italy) and the Oristano province (in the Sardinia Island) experienced the highest incidence rates during the study period. Our study shows a gradual, but rapid spread of WNND across Northern Italy from east to west and suggests the hypothesis that provinces close to Po River might present ecological and climatic conditions favourable to the virus circulation.  相似文献   
75.
The present study compared the quality of sperm collected by artificial vagina or pharmacologically induced ejaculation from a 10-year-old thoroughbred stallion with seminal vesiculitis. The pharmacological protocol involved intravenous administration of detomidine (0.01 mg/kg) and oxytocin (20 IU) and successfully induced ejaculation in all attempts of semen collection. Sperm motility, plasma membrane and acrosome integrity (PMAI), reactive oxygen species (ROS) levels, polymorphonuclear neutrophil (PMN) percentage, and bacterial profiles of fresh and cooled semen (5°C for 24 hr) were evaluated. Semen obtained by the pharmacological method presented reduced seminal volume, decreased PMN percentage and superior sperm motility in cooled samples. Moreover, higher PMAI and lower ROS levels were observed in semen collected by the pharmacological method. Therefore, pharmacologically induced ejaculation is an alternative to obtain semen with minimal contamination and with sperm of superior quality and longevity from stallions with seminal vesiculitis.  相似文献   
76.
Tropical Animal Health and Production - Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen...  相似文献   
77.
Phaseolus vulgaris L. is an important species that originated in Mesoamerica. A Mesoamerican and an Andean gene pool are usually distinguished in the domesticated forms. Many bean landraces are still cultivated in Italy and the Department of Applied Biology maintains an ex situ collection of 146 landraces. Although protection schemes are being developed in Italy, most landraces are extinct or at risk of extinction. To facilitate their conservation and use, geographical, morphological, biochemical and molecular (SSR) data were collected and analysed to estimate the diversity and the genetic structure of the collection. Data confirmed that both the Mesoamerican and the Andean gene pools were introduced in Italy and, although a distinction between the two gene pools exists, the Italian landrace diversity is clearly structured in three clusters that are not simply ascribable to the original gene pools. The observed structure appears also to be due to adaptation to the different environmental conditions determined by altitude. This was confirmed by assessing the presence of selective effects for some of the SSR used in this study. Finally, a certain extent of admixture in Italian landrace diversity suggests past (or recurring) hybridisation events among gene pools. The combined use of morphological, biochemical and molecular data clearly distinguished almost all the landraces. The data gathered here can assist landrace in situ protection schemes that are being developed in Italy, be used to register landraces in the European common catalogue of ‘conservation varieties’ for seed commercialisation and contribute to a better use of Italian common bean diversity in breeding for organic and conventional production systems.  相似文献   
78.
79.
Brassica oleracea L. is an important species that originated in the eastern Mediterranean area. From there, B. oleracea L. subsp. capitata (L.) DC. convar. botrytis (L.) Alef. var. italica Plenck (broccoli) was introduced into Italy where considerable diversification took place. Several landraces of broccoli, which are highly appreciated by local people for their organoleptic traits, are presently cultivated in both large fields and home gardens. In this study, 10 landraces, 4 synthetics derived from landraces and 4 of the most used F1 hybrids were characterised for morpho-physiological and molecular traits with the principal aim of feeding information into the landrace protection schemes being developed in Italy and into breeding programs. The landraces and derived synthetics are well differentiated from each other and from the F1 hybrids for important agronomic and genetic traits. The principal component analysis based on analysis of morpho-physiological traits showed that overall the 2 main components accounted for 67.74 % of the total variation. The neighbour joining tree, based on 23 microsatellite markers, grouped accessions into 2 main clusters. One includes one synthetic variety and 2 F1 hybrids, while the other cluster includes all the other accessions. There were also several sub clusters. Most of the materials examined showed within-accession diversity. The information gathered in this study can be used to protect landraces through the schemes presently being developed in Italy and to register them in the European common catalogue of “conservation varieties”. In situ (on-farm) conservation of landrace diversity is discussed with reference to landrace use.  相似文献   
80.
This work intended to study the rheological and textural behavior of gluten-free dough for “empanadas” and pie-crusts production. Traditionally, these products are made with non-fermented wheat-based dough. They are highly consumed in Latin America, but unsuitable for celiac people. Gluten matrix is a major determinant of the properties of dough, thus it must be replaced with other network forming components, such as hydrocolloids. Different hydocolloids were tested: hydroxypropylmethylcellulose (HPMC) and mixtures of xanthan/guar, and xathan/HPMC gums. Three different kinds of lipid phase were also studied; i.e. sunflower oil and low and high solid content margarine at two different levels (20–30%). Changes in rheological and textural properties during refrigerated storage were evaluated by dynamic oscillatory measurements and puncture and elongation tests on the unbaked dough. Best results were obtained using either of the hydrocolloid mixtures. Besides, the textural characteristics of cooked empanadas were also studied. Freezing before baking did not alter the quality of the crust in the products. ESEM micrographs revealed a continuous matrix formed by hydrocolloid entanglements. Starch granules were homogenously distributed in the dough and acted as inactive fillers. An untrained panel accepted the xanthan/HPMC dough with a 74/90 score and it was significantly preferred over a commercial gluten-free dough.  相似文献   
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