421 research outputs found
Effect of red wine maceration techniques on oligomeric and polymeric proanthocyanidins in wine, cv. Blaufrankisch
The influence of duration of maceration, of different maceration temperatures during the last two days of maceration, and the effect of malolactic fermentation on the content of oligomeric and polymeric proanthocyanidins in wine, cv. Blaufränkisch, were investigated using spectrophotometric methods and the NP-HPLC procedure. Results show that the duration of maceration affected the extraction from seeds more strongly, while heating of must primarily affected the extraction from skins. An increase of temperature from 25°C to 35°C during the last two days of maceration increased total anthocyanins and high molecular weight proanthocyanidins. Malolactic fermentation lowered the color of wine, the amount of total anthocyanins and total polyphenols and may reduce polymerization reactions of proanthocyanidins.
Red de agua y saneamiento en zona de piedemonte mendocino y análisis de precisión de instrumentos de medición
El presente trabajo constituye un informe de las tareas realizadas en la empresa Agua y Saneamiento de Mendoza (Aysam S.A.) en el marco del cumplimiento de las Practicas Profesionales Supervisadas (PPS) de la Carrera de Ingeniería en Agrimensura, dictada en la Universidad Juan Agustín Maza. El desarrollo de las Prácticas se llevó a cabo durante los meses de marzo, abril y mayo, en el Departamento de Estudios y Proyectos bajo la Gerencia de Ingeniería y Obras. Las tareas realizadas estuvieron fundamentalmente relacionadas a trabajos topográficos y se basaron en relevamientos planialtimétricos, saneamiento de títulos y servidumbres de acueducto, utilizando distintas técnicas y herramientas de medición como GPS; Nivel Óptico y Estación Total. El presente informe tiene como objetivos realizar levantamientos topográficos utilizados como base para la realización de nuevos Proyectos de Agua y Saneamiento, aplicar y ampliar conocimientos sobre los distintos métodos de medición, adquirir criterios en la toma de decisiones, desarrollar la capacidad de trabajo en equipo y profundizar los conocimientos respecto a las etapas de realización de obras
Dinamika populacije kvasca pri spontanim i induciranim alkoholnim fermentacijama vinskog mošta Zametovka
Inoculated fermentations, which are more rapid and more reliable than spontaneous fermentations, and assure predictable wine quality, are nowadays prevalent in Slovenia’s large-scale wine production. However, spontaneous fermentation strengthens local characteristics of wine and offers opportunities for technological innovation. In the 1999 vintage, spontaneous and inoculated fermentations of Zametovka (Vitis vinifera) grape must were studied. Zametovka is the main red variety in production of traditional Slovene red blend wine, Cvicek. The diversity of yeast species and strains in both of the investigated fermentations was determined by molecular and traditional identification methods. The outset of alcoholic fermentation, yeast growth kinetics, and yeast population dynamics presents the main differences between the examined fermentations. Yeast population diversity was higher in the spontaneous process. Dominant yeast isolates from spontaneous fermentation were identified as Candida stellata, Hanseniaspora uvarum and Saccharomyces cerevisiae; whereas Saccharomyces bayanus, Pichia kluyveri, Pichia membranifaciens and Torulaspora delbrueckiim were found less frequently. Dominant species in the inoculated fermentation was Saccharomyces cerevisiae; other species found in smaller numbers were Candida stellata, Hanseniaspora uvarum and Debaryomyces hansenii var. hansenii. Using PFGE, we were able to distinguish among 15 different Saccharomyces cerevisiae strains and three different Saccharomyces bayanus strains isolated from spontaneous fermentation, whereas, in the case of inoculated fermentation, only two Saccharomyces cerevisiae strains were found. Their chromosomal patterns coincide with the chromosomal patterns of the starter culture strains.U dana{njoj industrijskoj proizvodnji vina u Sloveniji prevladava inducirana fermentacija koja je brža i pouzdanija od spontane, a osigurava predvidivu kvalitetu vina. Spontana fermentacija pospješuje lokalne specifičnosti vina i omogućuje tehnološke inovacije. U berbi 1999. provedena je spontana i inducirana fermentacija mošta Zametovka (Vitis vinifera). Zametovka je glavna sorta crnog vina u proizvodnji Cvičeka, tradicionalnog slovenskog crnog vina. Raznolikost vrsta i sojeva kvasca u obje ispitivane fermentacije utvrđena je primjenom fizioloških i molekularnih testova. Glavne razlike između ispitivanih fermentacija sastojale su se u različitom početku alkoholne fermentacije, u kinetici rasta i dinamici populacije kvasca. Raznolikost u populaciji kvasca bila je veća pri spontanom procesu. Kao dominantni izolati kvasca pri spontanoj fermentaciji utvrđeni su Candida stellata, Hanseniaspora uvarum i Saccharomyces cerevisiae a rjeđe su se pojavljivali Saccharomyces bayanus, Pichia kluyveri, Pichia membranifaciens i Torulaspora delbrueckii. Pri induciranoj fermentaciji dominantna je vrsta Saccharomyces cerevisiae, a nađen je manji broj vrsta Candida stellata, Hanseniaspora uvarum i Debaryomyces hansenii var. hansenii. Koristeći gel-elektroforezu u pulsirajućem polju (PFGE), iz mošta pri spontanoj fermentaciji izolirano je 15 razli~itih sojeva Saccharomyces cerevisiae i tri različita soja Saccharomyces bayanus, a u induciranoj fermentaciji opažena su samo dva soja Saccharomyces cerevisiae. Njihova kromosomska struktura podudara se sa strukturom kromosoma soja starter-kulture
Associations between respiratory signs and abnormalities reported in thoracic CT scans of cats
Starvation combined with constant anode potential triggers intracellular electron storage in electro-active biofilms
The accumulation of electrons in the form of Extracellular Polymeric Substances (EPS) and poly-hydroxyalkanoates (PHA) has been studied in anaerobic processes by adjusting the access of microorganisms to the electron donor and final electron acceptor. In Bio-electrochemical systems (BESs), intermittent anode potential regimes have also recently been used to study electron storage in anodic electro-active biofilms (EABfs), but the effect of electron donor feeding mode on electron storage has not been explored. Therefore, in this study, the accumulation of electrons in the form of EPS and PHA was studied as a function of the operating conditions. EABfs were grown under both constant and intermittent anode potential regimes and fed with acetate (electron donor) continuously or in batch. Confocal Laser Scanning Microscopy (CLSM) and Fourier-Transform Infrared Spectroscopy (FTIR) were used to assess electron storage. The range of Coulombic efficiencies, from 25 to 82%, and the biomass yields, between 10 and 20%, indicate that storage could have been an alternative electron consuming process. From image processing, a 0.92 pixel ratio of poly-hydroxybutyrate (PHB) and amount of cells was found in the batch fed EABf grown under a constant anode potential. This storage was linked to the presence of living Geobacter and shows that energy gain and carbon source starvation were the triggers for intracellular electron storage. The highest EPS content (extracellular storage) was observed in the continuously fed EABf under an intermittent anode potential, showing that constant access to electron donor and intermittent access to the electron acceptor leads to the formation of EPS from the excess energy gained. Tailoring operating conditions can thus steer the microbial community and result in a trained EABf to perform a desired biological conversion, which can be beneficial for a more efficient and optimized BES.</p
Face processing limitation to own species in primates: a comparative study in brown capuchins, Tonkean macaques and humans
Most primates live in social groups which survival and stability depend on
individuals' abilities to create strong social relationships with other group
members. The existence of those groups requires to identify individuals and to
assign to each of them a social status. Individual recognition can be achieved
through vocalizations but also through faces. In humans, an efficient system
for the processing of own species faces exists. This specialization is achieved
through experience with faces of conspecifics during development and leads to
the loss of ability to process faces from other primate species. We hypothesize
that a similar mechanism exists in social primates. We investigated face
processing in one Old World species (genus Macaca) and in one New World species
(genus Cebus). Our results show the same advantage for own species face
recognition for all tested subjects. This work suggests in all species tested
the existence of a common trait inherited from the primate ancestor: an
efficient system to identify individual faces of own species only
THIN NITRIDE LAYERS AS PERMEATION BARRIERS
Permeation barriers represent one of the crucial fields in materials development for thermonuclear fusion. Primary objective of the barriers is to suppress the permeation of hydrogen isotopes (mainly tritium) from future thermonuclear fusion facilities. Secondary objective is to reduce hydrogen retention in structural materials, potentially also improving their corrosion resistance. Expected reactor conditions put high demands on the material, as well as on the final barrier quality. Key properties are tritium permeation reduction, absence of defects (especially cracks), high-temperature stability and corrosion resistance, and compatibility with structural materials (mostly ferritic-martensitic steels). Regarding industrial scale production, ability of the deposition method to coat large complex surfaces is desirable. Thin nitride layers, identified as promising permeation barriers, were prepared by diffusion-based nitridation and physical vapour deposition (PVD) and characterized
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