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61.
Irma Castro Claudio Alba Marina Aparicio Rebeca Arroyo Lorena Jiménez Leónides Fernández Ramón Arias Juan Miguel Rodríguez 《Journal of dairy science》2019,102(10):9298-9311
Mastitis is a highly prevalent condition that has a great impact on milk production and animal welfare, and often requires substantial management efforts. For this reason, it is generally considered an important threat to the dairy industry. Many microbial, host, and environmental factors can protect against, predispose to, or influence the development of mastitis. The objective of this work was to characterize the milk microbiota of Manchega ewes, and to compare samples from animals with and without a history of mastitis. We analyzed milk samples from 36 ewes belonging to 2 different farms (18 ewes from each farm) using culture-dependent and culture-independent techniques. We also analyzed several immune compounds to investigate associations of mastitis with 3 main variables: farm; history of mastitis or no mastitis; and parity number. Both culture-dependent and culture-independent techniques showed that ewe milk harbored a site-specific complex microbiota and microbiome. Staphylococcus epidermidis was the main species driving the difference between farm A (where it was the dominant species) and B (where it was not). In contrast, samples from farm B were characterized by the presence of a wide spectrum of other coagulase-negative staphylococci. Some of these species have already been associated with subclinical intramammary infections in ruminants. Of the 10 immune compounds assayed in this study, 3 were related to a history of mastitis [IL-8, IFN-γ, and IFN-gamma-induced protein 10 (IP-10)]. Increases in IL-8 concentrations in milk seemed to be a feature of subclinical mastitis in sheep, and in this study, this immune factor was detected only in samples from ewes with some episodes of mastitis and from the group with the highest somatic cell count. We also observed a positive correlation between the samples with the highest somatic cell count and IFN-γ and IP-10 levels. Our results suggest that these 3 compounds could be used as biomarkers for the negative selection of mastitis-prone animals, particularly when somatic cell count is very high. 相似文献
62.
Effect of borojo (Borojoa patinoi Cuatrecasas) three‐phase composition and gum arabic on the glass transition temperature 下载免费PDF全文
63.
Katerina Alba Grant M Campbell Vassilis Kontogiorgos 《Journal of the science of food and agriculture》2019,99(9):4189-4199
The structure and function of by-products of berry-processing industries are reviewed, with particular attention to dietary fibre (DF) and its effects in food products. The complex chemical composition and physicochemical characteristics of DF have been investigated and strategies for extraction of specific fractions that provide tailored technological and physiological functionality have been reviewed. The aim of this review is to describe in detail the structural composition and isolation methods of dietary fibre derived from berry by-products, and to explore their potential functionality in foods. The goal is to introduce DF from berry waste streams into the food chain, for which bread is a major vehicle. However, the appeal of bread lies in its aerated structure, for which DF is generally detrimental. The technological influence of DF on the formation and stabilization of the aerated structure of bread is therefore reviewed, in order to understand how to incorporate DF into bread while maintaining palatability. The aerated structure of bread is stabilized by two mechanisms: the gluten matrix and the liquid film surrounding bubbles. Incorporating DF successfully into bread requires understanding its interactions with both of these mechanisms. DF fractions from berries offer superior nutritional value compared to cereal fibre, potentially with less damage to bread structure, due to the higher proportion of soluble fibre. By-products from berry-processing industries could be used as a source of technologically and nutritionally distinctive DF to fabricate foods with enhanced nutritional value. © 2019 Society of Chemical Industry 相似文献
64.
65.
D‐isosorbide and 1,3‐propanediol as plasticizers for starch‐based films: Characterization and aging study 下载免费PDF全文
Kizkitza González Loli Martin Alba González Aloña Retegi Arantxa Eceiza Nagore Gabilondo 《应用聚合物科学杂志》2017,134(20)
In the present work, D‐isosorbide and 1,3‐propanediol are proposed as alternative plasticizers obtained from renewable resources. Plasticized starch films were prepared by solvent casting method. The influence of using different “green” plasticizers in the final properties of starch‐based films was analyzed. Besides, the characterization of the films was also performed after storage time in order to evaluate the effect of the plasticizer on aging. UV‐spectrophotometry results showed better optical properties for both glycerol and D‐isosorbide films with higher transparency. The thermal and mechanical properties resulted influenced by the nature of the plasticizer. It was demonstrated that water vapor permeability was governed by the starch‐water interactions, whereas the oxygen permeability depended on the plasticizer's nature. The storage time affected the surface, mechanical, and thermal properties of the plasticized starch films. Atomic force microscopy results concluded that the topography of the films changed due to aging. The use of D‐isosorbide as plasticizer reduced the evolution of the mentioned properties and enhanced the reliability of the material. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44793. 相似文献
66.
Rodriguez-Garcia G Molinos-Senante M Hospido A Hernández-Sancho F Moreira MT Feijoo G 《Water research》2011,45(18):5997-6010
The objective of wastewater treatment plants (WWTPs) is to prevent pollution. However, it is necessary to assess their sustainability in order to ensure that pollution is being removed, not displaced. In this research, the performance of 24 WWTPs has been evaluated using a streamlined Life Cycle Assessment (LCA) with Eutrophication Potential (EP) and Global Warming Potential (GWP) as environmental indicators, and operational costs as economic indicators. WWTPs were further classified in six typologies by their quality requirements according to their final discharge point or water reuse. Moreover, two different functional units (FU), one based on volume (m3) and the other on eutrophication reduction (kg PO43− removed) were used to further determine sustainability. A correlation between legal requirements and technologies used to achieve them was found: Organic matter removal plants were found to be less costly both in environmental and economic terms if volume was used as the functional unit, while more demanding typologies such as reuse plants showed a trade-off between lower EP and higher cost and GWP; however, this is overcome if the second FU is used instead, proving the sustainability of these options and that this FU better reflects the objectives of a WWTP. 相似文献
67.
Ince Laurence P.; Greene Renee Y.; Alba Augusta; Zaretsky Herbert H. 《Canadian Metallurgical Quarterly》1987,6(2):173
Treated 30 individuals (aged 24–82 yrs) with subjective tinnitus aurium with a matching-to-sample feedback procedure. Ss' tinnitus sounds were reproduced audiometrically on all characteristics and were presented to them in the noninvolved ear or in both ears when the tinnitus was binaural. This experimental sound was then reduced in 5-db steps within sessions, and Ss had the task of concentrating on reducing the loudness of their tinnitus until a match was achieved between it and the experimental sound at each new db level. Results show a significant difference in db levels from baseline to final training session. Nearly all Ss demonstrated a marked reduction in tinnitus loudness, with several eliminating it completely. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
R Ferrero Doria P Guzmán Valls J López Alba M Tomás Ros JL Rico Galiano LO Fontana Compiano 《Canadian Metallurgical Quarterly》1996,20(4):380-383
SETTING: A voluntary community health worker programme, in the Western Cape, South Africa, utilizing volunteers to administer directly observed therapy to tuberculosis (TB) patients. OBJECTIVE: This study describes the perceptions of health team members regarding the voluntary community health worker project. DESIGN: A qualitative, participatory research study utilizing focus groups. RESULTS: TB was perceived by the health team to be a stigmatized disease causing some patients to be reluctant to be associated with the TB control programme. Despite the project's dedicated approach to case-holding, volunteers expressed the need to develop skills in providing more comprehensive care. The volunteers appear to administer a more personalized service to TB patients and can bridge the gap between TB patients and the health agency. CONCLUSION: Sustained evaluation and support seem to be a vital tool in integrating a volunteer project into a health team approach. Its effectiveness appears to depend to a large degree on the people involved. 相似文献
69.
Teresa Auguet Alba Berlanga Esther Guiu-Jurado Salomé Martinez José Antonio Porras Gemma Aragonès Fátima Sabench Mercé Hernandez Carmen Aguilar Joan Josep Sirvent Daniel Del Castillo Cristóbal Richart 《International journal of molecular sciences》2014,15(12):22173-22187
Lipid accumulation in the human liver seems to be a crucial mechanism in the pathogenesis and the progression of non-alcoholic fatty liver disease (NAFLD). We aimed to evaluate gene expression of different fatty acid (FA) metabolism-related genes in morbidly obese (MO) women with NAFLD. Liver expression of key genes related to de novo FA synthesis (LXRα, SREBP1c, ACC1, FAS), FA uptake and transport (PPARγ, CD36, FABP4), FA oxidation (PPARα), and inflammation (IL6, TNFα, CRP, PPARδ) were assessed by RT-qPCR in 127 MO women with normal liver histology (NL, n = 13), simple steatosis (SS, n = 47) and non-alcoholic steatohepatitis (NASH, n = 67). Liver FAS mRNA expression was significantly higher in MO NAFLD women with both SS and NASH compared to those with NL (p = 0.003, p = 0.010, respectively). Hepatic IL6 and TNFα mRNA expression was higher in NASH than in SS subjects (p = 0.033, p = 0.050, respectively). Interestingly, LXRα, ACC1 and FAS expression had an inverse relation with the grade of steatosis. These results were confirmed by western blot analysis. In conclusion, our results indicate that lipogenesis seems to be downregulated in advanced stages of SS, suggesting that, in this type of extreme obesity, the deregulation of the lipogenic pathway might be associated with the severity of steatosis. 相似文献
70.
Formic acid decomposition on Au catalysts: DFT,microkinetic modeling,and reaction kinetics experiments 下载免费PDF全文
Ronald Carrasquillo‐Flores Ana C. Alba‐Rubio James A. Dumesic Manos Mavrikakis 《American Institute of Chemical Engineers》2014,60(4):1303-1319
A combined theoretical and experimental approach is presented that uses a comprehensive mean‐field microkinetic model, reaction kinetics experiments, and scanning transmission electron microscopy imaging to unravel the reaction mechanism and provide insights into the nature of active sites for formic acid (HCOOH) decomposition on Au/SiC catalysts. All input parameters for the microkinetic model are derived from periodic, self‐consistent, generalized gradient approximation (GGA‐PW91) density functional theory calculations on the Au(111), Au(100), and Au(211) surfaces and are subsequently adjusted to describe the experimental HCOOH decomposition rate and selectivity data. It is shown that the HCOOH decomposition follows the formate (HCOO) mediated path, with 100% selectivity toward the dehydrogenation products (CO2 + H2) under all reaction conditions. An analysis of the kinetic parameters suggests that an Au surface in which the coordination number of surface Au atoms is ≤4 may provide a better model for the active site of HCOOH decomposition on these specific supported Au catalysts. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1303–1319, 2014 相似文献