4,858 research outputs found
Arabic gum, a new strategy for microbiological control in the dairy industry
The nutritional quality loss of food, usually is caused by microbial growth during different stages of production. Particularly in raw milk, the initial microbial content will affect the quality, shelf life and safety of processed milk and its derivatives. Traditionally, one of the strategies most used for reducing the risk of microbial contamination of raw milk, is storage under refrigeration immediately after to milking. However, this selectively favor the development of psychrotrophic microorganisms that can produce heat stable extracellular enzymes, causing alterations in the chemical composition and nutritional value of milk. In the last decade, the demand for minimally processed, easily prepared, and ready-to-eat fresh food products has grown globally, prompting the development of new methodologies as alternatives to thermal treatment. A growing trend is the addition of preservatives of natural sources, as a safe and healthy alternative to synthetics preservatives. The Arabic Gum (AG) is an edible biopolymer obtained as exudates of trees of Acacia, which is being widely used as a stabilizer, a thickener, and an emulsifier. However, to date, no antimicrobial activities studies have been conducted against psychrotrophics microorganisms. The aim of this work was to evaluate the effect of the addition of AG over the psychrotrophics bacterial growth, and viability. Several bacteria isolated from raw milk (Enterobacter spp.) were cultivated with different concentration of AG (0, 10, 20, 75, 100, 200, 400 M) during a period of 7 days at 4ÂșC and analyzed each 24 h. The bacterial growth in different conditions was evaluated by CFU counts, viability assays was performed using the LIVE/DEAD BacLight Bacterial Viability Kit (FACS), and metabolic activity was determined by colorimetric assay using tetrazolium salt (MTT). We observed that the addition of 200 and 400 M AG controlled proliferation of bacterial growth in more than a 50%, respect to the control condition and these effects were dose-dependent. In another hand, AG did not show significantly effect on the bacterial viability evaluated by the incorporation of propidium iodure. However using the tetrazolium salt as MTT we could determine that 75, 100, 200 and 400 M of AG were able to inhibit the metabolic activity of psychrotrophics bacterial growth significantly in all the assayed times. These data shown that AG had an important effect in the initial proliferation over psychrotrophic bacterial milk, which was maintained during analyzed times. Is important to hightlight that, for dairy factory the initial times are determinants to conserve the milk quality up to industrial processing, improving nutritional value in the final product. In base of these results, we can suggest that AG provides an additional beneficial effect to their usually technological use in food industry.Fil: Boiero, MarĂa Laura. Universidad TecnolĂłgica Nacional. Facultad Regional Villa MarĂa. Departamento de IngenierĂa QuĂmica; Argentina.Fil: Gonzalez Estevez, Virginia. Universidad TecnolĂłgica Nacional. Facultad Regional Villa MarĂa. Departamento de IngenierĂa QuĂmica; Argentina.Fil: Bachetti, R. Universidad Nacional de Villa MarĂa. Centro de Investigaciones y Transferencia de Villa MarĂa; Argentina.Fil: Morgante, C. Universidad Nacional de Villa MarĂa. Centro de Investigaciones y Transferencia de Villa MarĂa; Argentina.Fil: Porporatto, C. Universidad Nacional de Villa MarĂa. Centro de Investigaciones y Transferencia de Villa MarĂa; Argentina.Fil: Montenegto, Mariana. Universidad TecnolĂłgica Nacional. Facultad Regional Villa MarĂa. Departamento de IngenierĂa QuĂmica; Argentina.Peer Reviewe
Highly Chemoselective NH- and O-Transfer to Thiols Using Hypervalent Iodine Reagents: Synthesis of Sulfonimidates and Sulfonamides
Aryl thiols can be selectively converted to sulfonimidates or sulfonamides with three new S-X connections being made selectively in one pot. Using hypervalent iodine reagents in the presence of ammonium carbamate, NH- and O-groups are transferred under mild and practical conditions. Reducing the loading of ammonium carbamate changed the product distribution, converting the sulfonimidate to the sulfonamide. Studies into the possible intermediate species are presented, suggesting that multiple pathways may be possible via sulfinate esters, or related intermediates, with each species forming the same products
Viability of transcervical embryo transfer in goats.
Embryo transfer consists in the deposition of the embryo in the recipient uterus. The results of recipient?s fertility vary widely depending on the origin of these embryos: fresh or cryopreserved and produced in vivo or in vitro. Typically, pregnancy rates ranging from 40 to 80% are reported. The objective of this study was to test the feasibility of non-surgical embryo transfer of goat fresh embryos.Proceedings of the 29th Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Gramado, RS, Brazil, August 20th to 23rd, 2015, and 31st Meeting of the European Embryo Transfer Association (AETE); Ghent, Belgium, September 11th and 12th, 2015. Abstract
Psychological Intervention for Development of Disease Awareness in Addicts: Villa Colibri Therapeutic Community of Santiago De Cuba
In the research, a Mixed Method was used and the execution was through a sequential exploratory design. For the initial diagnosis was used, semi-structured interview, sentence completion test, disease awareness questionnaire, attitude to the disease, interpersonal relationships, and conflict management, were the dimensions of the awareness indicator of the disease. Based on the results of the diagnosis, the Psychological Intervention Program was developed, based on the cognitive-behavioral model with a humanistic approach. with respect to the attitude towards the disease, the subjects predominated in ambivalence in 70.6% and non-consciousness in 23.5%, referring to interpersonal relationships, ambivalent in 58.8% and not healthy in 29.4% and conflict management was inconsistent in 70.6%, and inadequate in 23.5%, after the development of the program, positive attitude increased 52.9% and ambivalence decreased to 41.2%, healthy interpersonal relationships grew to 47.1% and adequate conflict management was imposed in 58.8% of the sample. The lack of awareness of the disease in patients was identified, the preliminary results of the application of the program proved to be very useful to develop awareness of the disease in the subjects studied, thus achieving a better therapeutic adherence
THE HIGH CADENCE TRANSIENT SURVEY (HITS). I. SURVEY DESIGN AND SUPERNOVA SHOCK BREAKOUT CONSTRAINTS
IndexaciĂłn: Web of Science; Scopus.We present the first results of the High Cadence Transient Survey (HiTS), a survey for which the objective is to detect and follow-up optical transients with characteristic timescales from hours to days, especially the earliest hours of supernova (SN) explosions. HiTS uses the Dark Energy Camera and a custom pipeline for image subtraction, candidate filtering and candidate visualization, which runs in real-time to be able to react rapidly to the new transients. We discuss the survey design, the technical challenges associated with the real-time analysis of these large volumes of data and our first results. In our 2013, 2014, and 2015 campaigns, we detected more than 120 young SN candidates, but we did not find a clear signature from the short-lived SN shock breakouts (SBOs) originating after the core collapse of red supergiant stars, which was the initial science aim of this survey. Using the empirical distribution of limiting magnitudes from our observational campaigns, we measured the expected recovery fraction of randomly injected SN light curves, which included SBO optical peaks produced with models from Tominaga et al. (2011) and Nakar & Sari (2010). From this analysis, we cannot rule out the models from Tominaga et al. (2011) under any reasonable distributions of progenitor masses, but we can marginally rule out the brighter and longer-lived SBO models from Nakar & Sari (2010) under our best-guess distribution of progenitor masses. Finally, we highlight the implications of this work for future massive data sets produced by astronomical observatories, such as LSST.http://iopscience.iop.org/article/10.3847/0004-637X/832/2/155/meta;jsessionid=76BDFFFE378003616F6DBA56A9225673.c4.iopscience.cld.iop.or
New variable separation approach: application to nonlinear diffusion equations
The concept of the derivative-dependent functional separable solution, as a
generalization to the functional separable solution, is proposed. As an
application, it is used to discuss the generalized nonlinear diffusion
equations based on the generalized conditional symmetry approach. As a
consequence, a complete list of canonical forms for such equations which admit
the derivative-dependent functional separable solutions is obtained and some
exact solutions to the resulting equations are described.Comment: 19 pages, 2 fig
On Soliton-type Solutions of Equations Associated with N-component Systems
The algebraic geometric approach to -component systems of nonlinear
integrable PDE's is used to obtain and analyze explicit solutions of the
coupled KdV and Dym equations. Detailed analysis of soliton fission, kink to
anti-kink transitions and multi-peaked soliton solutions is carried out.
Transformations are used to connect these solutions to several other equations
that model physical phenomena in fluid dynamics and nonlinear optics.Comment: 43 pages, 16 figure
Catheter-based intervention for symptomatic patient with severe mitral regurgitation and very poor left ventricular systolic function - Safe but no room for complacency
Many patients with left ventricular systolic dysfunction have concomitant mitral regurgitation (MR). Their symptoms and prognosis worsen with increasing severity of MR. Percutaneous MitraClip((R)) can be used safely to reduce the severity of MR even in patients with advanced heart failure and is associated with improved symptoms, quality of life and exercise tolerance. However, a few patients with very poor left ventricular systolic function may experience significant haemodynamic disturbance in the peri-procedural period. We present three such patients, highlighting some of the potential problems encountered and discuss their possible pathophysiological mechanisms and safety measures.published_or_final_versio
Transect walks : method sensitivity for on-farm welfare evaluation in turkeys
There is increasing consumer demands for livestock and poultry products that meet minimum animal
welfare standards during their production cycle. Additionally, a growing number of farmers are aware
about full compliance with the animal welfare standards that could play an important economic role in
commercial intensive productions. Indeed, animal welfare assessment protocols have meaningful effects
to promote and guarantee the on-farm safeguard animal standards. Transect walks method appeared to
provide a practical approach to welfare assessment in broilers farms. Because of the similarities of meat
poultry production, this method could be considered a reasonable approach for turkey welfare
evaluation in terms of time demands, within costs and feasibility. The aim of this study was to
determine the sensitivity of this method at 3 commercial turkey farms with similar facilities (Animal
Welfare Indicators project, FP7-KBBE-2010-4). In this study, 10 commercial female-turkey flocks (6
houses with identical management), ranging from 3,212 to 6,000 birds and belonging to the same
company were evaluated one week before slaughter. On turkey farms, walking through the house is a
routine daily procedure to check the health status of the birds. Two previously trained assessors in
performing the transect methodology and properly assessing the selected indicators, evaluated each
paired house sequentially and independently within the same day by walking through predefined
transect bands (1 to 4) in random order. The animal-based indicators considered were: immobility,
lameness, wounds and featherless. The statistical model used was GLM in the GENMOD procedure
(SAS V9). The results showed that this welfare assessment method highlights even small variation
among houses for the considered variables. In fact, there were significant difference across houses
(P=0.0021, P=0.0006, P=0.0081 and P=0.0003) for all the evaluated indicators respectively. Differences
across observers were detected for wounds and featherless (P<0.0001). These results may be due to the
difficulties in assessing equally these parameters while walking. On the contrary, lameness, probably the
most important welfare problem in meat poultry, showed a good concordance between observers (P=
0.361). These preliminary findings suggest that this new approach has potential as a tool for on-farm
welfare evaluation, which may be worthwhile to be further developed
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