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541.
Manuela Mariotti Stefania Iametti Carola Cappa Patrizia Rasmussen Mara Lucisano 《Journal of Cereal Science》2011
Formation of a gluten protein network is fundamental for the texture and the overall quality of pasta. Replacement of the gluten network in gluten-free pasta is a major technological challenge, and the conventional technological processes have to be adapted to non-gluten formulations. The wide variety of raw materials and technologies used in the production of commercial gluten-free pasta stems from the – still on-going – search for solutions to these problems. The aim of this study was to evaluate the characteristics of different commercial gluten-free spaghetti currently available on the market, focusing on starch and protein organisation. Taking into account the chemical and biochemical properties of the samples, and their relationships to the physical characteristics of these products we looked at how some molecular properties relate to the final structure and quality of gluten-free pasta. Phenomena related to starch retrogradation were found to play a central role for the final texture of the products. At the same time, the origin of proteins included in the formulation was found to govern the protein–protein interactions, especially in those samples including proteins from different vegetable sources. 相似文献
542.
Jaramillo C Ochoa D Contreras L Pagani M Carvajal-Ortiz H Pratt LM Krishnan S Cardona A Romero M Quiroz L Rodriguez G Rueda MJ de la Parra F Morón S Green W Bayona G Montes C Quintero O Ramirez R Mora G Schouten S Bermudez H Navarrete R Parra F Alvarán M Osorno J Crowley JL Valencia V Vervoort J 《Science (New York, N.Y.)》2010,330(6006):957-961
Temperatures in tropical regions are estimated to have increased by 3° to 5°C, compared with Late Paleocene values, during the Paleocene-Eocene Thermal Maximum (PETM, 56.3 million years ago) event. We investigated the tropical forest response to this rapid warming by evaluating the palynological record of three stratigraphic sections in eastern Colombia and western Venezuela. We observed a rapid and distinct increase in plant diversity and origination rates, with a set of new taxa, mostly angiosperms, added to the existing stock of low-diversity Paleocene flora. There is no evidence for enhanced aridity in the northern Neotropics. The tropical rainforest was able to persist under elevated temperatures and high levels of atmospheric carbon dioxide, in contrast to speculations that tropical ecosystems were severely compromised by heat stress. 相似文献
543.
544.
Nika Vero Silvo Hribernik Patrizia Andreozzi Majda Sfiligoj-Smole 《Fibers and Polymers》2009,10(5):716-723
The aim of this research was to study TiO2 nanocoatings formation and to investigate their self-cleaning effects when applied on cellulose materials. Two different
approaches for achieving nanocoatings were used. First, coatings were generated in situ through an acid and alkaline catalyzed
sol-gel process with or without added water. Another type of coatings was prepared starting from commercial TiO2 P25 powder. In order to acquire homogeneous coatings from TiO2 P25 nanoparticles with uniform nanoparticles size distribution, pH of aqueous TiO2 P25 dispersions was varied. The dispersion preparation conditions were studied by dynamic light scattering (DLS) and zeta
potential (ζ-potential) analysis. The resulting TiO2 nanocoatings were analyzed in terms of their surface morphology using scanning electron microscopy (SEM). Nanocoatings obtained
from pure aqueous dispersions of TiO2 P25 nanoparticles were inhomogeneous with huge agglomerates; however by changing the pH of dispersion and consequently changing
the surface charge of TiO2 P25 nanoparticles as well, more homogeneous nanocoatings with uniform TiO2 nanoparticles distribution were prepared. Significant differences between solgel derived coatings were observed. Sol-gel
process without added water yielded more homogeneous coatings than sol-gel process with addition of water. Completely different
surface morphologies were obtained using alkaline or acid catalyst. Acid catalyzed sol-gel process yielded nanocoatings with
long, extended, thin structures; contrary, under alkaline conditions particles grow in size with decrease in number. Fourier
transform infrared (FTIR) spectroscopy was used to study the coatings’ microstructure. Furthermore the formation of mono-disperse
nanoparticles on the fiber surface resulted in enhanced photocatalytic activity. Degradation of colored stain applied on TiO2-treated samples was investigated by colorimetric measurements. Photocatalytic activity of nanocoatings prepared via acid
catalyzed sol-gel process without water addition was comparable to that of nanocoatings derived from aqueous dispersions of
commercial TiO2 P25 nanoparticles. 相似文献
545.
546.
Successful medical management of a domestic longhair cat with subdural intracranial empyema and multifocal pneumonia
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547.
Roberta Roberti Fabio Osti Gloria Innocenti Adamo Domenico Rombolà Stefano Di Marco 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):151-162
Among the fungi associated with the kiwi wood diseases, the vascular pathogen Phaeoacremonium minimum can infect plants already at nursery stage, without any external symptoms. At the moment, there are not effective control strategies. The effect of soil treatments applicable in organic agriculture was evaluated in two-years experiments on potted kiwi plants artificially inoculated with P. minimum. The soil treatments were based on commercial formulations of iron chelate, silicon, neem paste, Trichoderma afroharzianum strain T22, and cover cropping with selected perennial Poaceae. Cover cropping and iron chelate treatments enhanced the iron availability for the plants and significantly reduced wood necrosis caused by the pathogen. Both treatments also produced an increase of hairy root proliferation, so the plants were able to better cope with stress conditions. Laboratory assays showed the role of iron on the pathogen growth and its pathogenesis enzyme activities. 相似文献
548.
Albert Herrero Cristina Buendía Gianbattista Bussi Sergi Sabater Damià Vericat Antoni Palau Ramon J. Batalla 《Journal of Soils and Sediments》2017,17(11):2677-2690
Purpose
Erosion processes at the catchment scale control a basin’s morphology and sediment patterns in the river network. Eroded sediments are transported and deposited downstream and may cause environmental problems and relevant effects on water storage and hydropower infrastructures. Quantification of water and sediment yield is complex due to the physical processes involved and their temporal and spatial variability, especially at the light of current global change.Materials and methods
Numerical models that use spatially distributed information constitute a useful tool for these estimates, when sufficient input data are available. In this study, we applied the hydrological and sedimentological TETIS model to determine the patterns of water and sediment yield in a large mountain catchment. Flow discharge data obtained from two gauged stations were used for calibration and validation of the hydrological sub-model. Data from two reservoir bathymetries at the outlet of the study area were used for calibration of the sedimentological sub-model. After model calibration, several scenarios of climate and land use change were simulated.Results and discussion
Climate scenarios show a general decrease in average annual precipitation and an increase in temperature, associated with an increase in extreme rainfall events. Global change scenarios lead to a counteracting effect between the increase in sediment transport during extreme events and the decrease in sediment erosion associated with afforestation following the abandonment of agricultural land. In the case of the most extreme climate scenario combined with total catchment deforestation, the model indicates a complete siltation of the reservoir by 2050.Conclusions
Model performance emphasizes its potential as a tool for evaluating water and sediment yield for large catchments, as well as of its usefulness for water and sediment management in light of future climate and land use change scenarios.549.
JL Yániz F López‐Gatius I García‐Ispierto G Bech‐Sàbat B Serrano C Nogareda JA Sanchez‐Nadal S Almeria P Santolaria 《Reproduction in domestic animals》2010,45(4):699-705
The aim of this study was to determine if the factors affecting the abortion rate in dairy herds with high incidence of Neospora‐associated abortions are different in pregnancies of cows and heifers chronically infected with Neospora caninum. In heifers (n = 229), an increase in the cumulative number of days with a mean relative humidity (RH) lower than 60% during the second trimester of gestation increases the risk of abortion. Yet, the likelihood of abortion was 7.6 times lower for pregnant heifers inseminated with Limousin bull semen, compared with those inseminated with Holstein‐Friesian bull semen. In pregnancies of parous cows (n = 521), an increase in rainfall and in the cumulative number of days with a mean RH lower than 60% during the second trimester of gestation increased the abortion rate. However, in contrast, an increase in the lactation number produced a decrease in the abortion rate, with a likelihood of abortion 4.8 times lower for pregnant cows inseminated with Limousin bull semen, and three times lower for those inseminated with Belgian Blue bull semen, compared with dairy cows inseminated with Holstein‐Friesian bull semen. Finally, the likelihood of abortion was 3.2 times lower for pregnancies of parous cows with low antibody titres against N. caninum (6–30 units) as compared to those with high antibody titres (≥30 units), whereas in heifers this variable had no effect. The practical recommendations of the present study include the control of the cow environment during the second trimester of gestation, the priority of culling for parous cows with higher antibody titres against N. caninum and the insemination of Neospora‐seropositive cows with semen from the Limousin breed. 相似文献
550.
J. Stavisky G.L. Pinchbeck A.J. German S. Dawson R.M. Gaskell R. Ryvar A.D. Radford 《Veterinary microbiology》2010,140(1-2):18-24
In order to determine the prevalence of canine enteric coronavirus (CECoV) in the general dog population, faecal samples were obtained in a cross-sectional study of 249 dogs presenting for any reason at veterinary practices randomly selected from across the UK. Demographic and clinical data was obtained for each of the samples, including signalment, number of dogs in the household, reason for visiting the practice, and any recent history of diarrhoea. The samples were tested by RT-PCR for the presence of both type I and type II CECoV. Seven samples were positive (three from dogs in the same household), a prevalence of 2.8% (95% confidence intervals 1.1–5.7). Phylogenetic analysis of partial M gene sequences revealed that all seven positive samples grouped with type I CECoV, the first report of this virus in the UK. None of the positive dogs presented for gastrointestinal disease. Interestingly five of the positive dogs from three separate households were aged over 6 years, suggesting that older dogs may play an important role in the persistence of CECoV in such populations. 相似文献