Searching for Evidence of Life in Deep Time and Space

Cyanobacterial mats provide insights into ancient benthic microbial communities and their biosignatures. Thick mats occupy hypersaline saltern ponds at Guerrero Negro, Baja California, Mexico. Mat biota maintains rapid rates of biogeochemical processes under steep and rapidly changing environmental gradients. Cycling of C, O, and S all increased identically with temperature, indicating the tight coupling of these cycles. An enormous microbial diversity exhibits a highly structured spatial distribution of populations. Combined universal clone libraries from all mat layers indicated Bacteria/Archaea/Eukarya ratios of 57:7:1. More than 10,000 unique bacterial sequences were present. The relative abundance of Archaea increased with depth - below 10 cm, solvent-extractable archaeal lipids were twice as abundant as bacterial lipids. Only 15 species of Eukarya were found among 890 clones analyzed. Degradation of the mats insoluble macromolecular organic fraction (IMOM) by hydropyrolysis released a complex variety of linear, branched and polycyclic alkane structures, e.g., hopanes, methylhopanes and steranes. Covalent binding of these biosignatures into IMOM aids their long-term geological preservation. Mars rover missions revealed evidence of long-lived fluvial lacustrine systems and organics in associated mudstones. NASAs Mars 2020 rover mission will examine sediments in Jezero crater, including a delta and shoreline carbonate deposits, environments that on Earth have sustained microbial mats

Sample positioning in neutron diffraction experiments using a multi-material fiducial marker

An alternative sample positioning method is reported for use in conjunction with sample positioning and experiment planning software systems deployed on some neutron diffraction strain scanners. In this approach, the spherical fiducial markers and location trackers used with optical metrology hardware are replaced with a specifically designed multi-material fiducial marker that requires one diffraction measurement. In a blind setting, the marker position can be determined within an accuracy of ±164 µm with respect to the instrument gauge volume. The scheme is based on a pre-determined relationship that links the diffracted peak intensity to the absolute positioning of the fiducial marker with respect to the instrument gauge volume. Two methods for establishing the linking relationship are presented, respectively based on fitting multi-dimensional quadratic functions and a cross-correlation artificial neural network

A Reproducible Capillary Gas Chromatographic Technique for the Determination of Specific Terpenes in Grape Juice and Wine

A reliable and highly reproducible technique for the Freon 11 extraction of 16 terpenes from grape juice and wine and their gas chromatographic analyses is presented. Terpene concentrations were calculated as relative values by means of an internal standard. Standard deviations of the terpenes analysed varied between 1,2% and 13,9% for non-settled grape juice and between 2,0% and 5,2% for wine. Variation in gas chromatographic retention times was between 0,04 and 0,1 minutes. The freon extracts of grape juice and wine could be stored at minus 12°C for up to six days without marked changes occurring in the relevant terpene concentrations

Effect of Different Wine-Making Techniques on the Composition and Quality of Pinotage Wine. II. Juice/Skin Mixing Practices

The effect of different juice/skin mixing practices (punching-down of the cap, pumping-over of the juice and the rotor action, and the frequency at which these actions were performed) on Pinotage wine composition and quality, was investigated over three seasons (2000 to 2002). Wines were analysed for total polyphenols (flavonoids, tannins, anthocyanins) and esters, and sensorially evaluated for Pinotage cultivar character (berry/plum) intensity and overall wine quality. The punching-down and rotor treatments yielded the highest, and the pumping-over treatment the lowest total polyphenol concentrations. Although it appeared that the 3-hourly action yielded slightly higher polyphenol concentrations than the 1-hourly action, no statistical differences were observed between the two treatments.  Irrespective of season, the rotor treatment yielded the highest acetate ester concentrations. The corresponding wines reflected the individual treatments to a great extent, and in general the wine qualities of the punching-down and rotor treatments were of the same order, but higher than those of the pumping-over treatment. Wine quality did not differ significantly between the 1- and 3-hourly treatments, irrespective of the mixing technique and season

Terpene concentrations and wine quality of Vitis vinifera L. cv. Gewürztraminer as affected by grape maturity and cellar

The effect of grape maturity and juice treatments, namely skin-contact and heat treatment, on individual free terpene concentrations in Gewürztraminer juices and wines, as weil as on wine qualjty, was investigated. Total free volatile terpenes and total potentially volatile terpenes were also monitored during ripening of the grapes. Linalool, hotrienol, a -terpineol, citronellol, nerol, geraniol, diendiol-1, trans-geranic acid and the furan linalool oxides were analysed gas chromatographically. Wirre quality characteristics, such as fruitiness/ester-like, spiciness/terpene-like and overall wine quality of the wirres were evaluated sensorially. An increase in grape maturity caused marked increases in total bound terpene, as weil as in most individual terpene concentrations. Skin-contact for 4 and 15 h, respectively, and a combined treatment of 15 h skin-contact and heat treatment caused significant increases in the concentrations of the majority of terpenes analysed. Heat treatment resulted in decreases in geraniol, nerol and citronellol concentrations. The combined skin-contact and heat treatment resulted in higher intensities of fruitiness and spiciness, as weil as overall wine quality

Effect of storage time and temperature on the formation of dimethyl sulphide and on white wine quality

Wines of the cultivars Chenin blanc, Colombar and Riesling were stored at 0, 10, 20 and 30 °c for 16 weeks. The wines were analysed periodically by gas chromatography for dimethyl sulphide (DMS) and sensorily evaluated for the characteristic maturation bouquet to investigate the effect of storage time and temperature on the formation of DMS. Ethyl acetate (EtAc) and varietal bouquet were investigated simultaneously. It was found that both DMS concentration and maturation bouquet increased with an increase in storage time and temperature. Furthermore, the EtAc concentration and varietal bouquet decreased. A highly significant relationship was found between DMS concentration and the bottle maturation bouquet of the wines confirming the important contribution of DMS to wine quality. Furthermore, a significant relationship was found between EtAc concentration and varietal bouquet. It was also found that the rate of formation of DMS in white wines differed among the different cultivars.Der Einfluß der Lagerungsdauer und -temperatur auf die Bildung von Dimethylsulfidund auf die Qualität von WeißweinWeine der Sorten Chenin blanc, Colombar und Riesling  wurden bei 0, 10, 20 und 30 oc 16 Wochen lang gelagert. In periodischen Abständen wurden gaschromatographische Bestimmungen des Dimethylsulfidgehaltes (DMS) und sensorische Qualitätsprüfungen zum Nachweis des charakteristischen Reifebuketts vorgenommen. Gleichzeitig wurden Äthylacetat (EtAc) und Sortenbukett untersucht. Sowohl die DMS-Konzentration als auch das Reifebukett nahmen mit der Dauer der Lagerung und der Höhe der Lagerungstemperatur zu. Ferner ging die EtAc-Konzentration zurück, und das Sortenbukett wurde schwächer.Zwischen der DMS-Konzentration und dem Flaschenreifebukett der Weine wurde eine hochsignifikante Beziehung nachgewiesen, womit die Bedeutung von DMS für die Weinqualität unterstrichen wird. Ferner wurde eine signifikante Beziehung zwischen der EtAc-Konzentration und dem Sortenbukett festgestellt. Außerdem wurde gefunden, daß die DMS-Bildung in den Weinen der einzelnen weißen Sorten mit unterschiedlicher Geschwindigkeit ablief

Wisdom and narrative: Dealing with complexity and judgement in translator education

This article explores wisdom as concept to guide translator education in institutions of higher education. It uses the work of Paul Baltes to posit wisdom as the orchestration of mind and virtue for the common good. Wisdom then signifies the outcome of translator education. Narrative is a mode of communication that is able to foster wisdom. In this respect, the article elaborates on Baker’s use of narrative theory in translation studies.In conclusion certain aspects of education are suggested, which would enhance translators’ wisdom so that they may be able to judge ill-structured, complicated communication situations in order to enhance communication

Effect of Different Wine-Making Techniques on the Composition and Quality of Pinotage Wine. I. Low-Temperature Skin Contact Prior to Fermentation

The effect of low-temperature skin contact prior to fermentation (1, 2 and 4 days at 10°C and 15°C, respectively) on Pinotage wine composition and quality was investigated over four seasons (1999 to 2002). The extraction of total polyphenols (total flavonoids, total tannins and total anthocyanins) was followed during skin contact and fermentation.  Wines were analysed for total polyphenols and esters, and sensorially evaluated for Pinotage cultivar character (berry/plum) intensity and overall wine quality. Polyphenol extraction rates differed greatly between the skin contact treatments. Polyphenol concentrations in the final wines increased slightly with an increase in prefermentation skin contact tune. Acetate ester concentrations generally decreased with an increase in prefermentation skin contact time. Wine quality differed significantly between some treatments and the most typical and highest quality Pinotage wines were produced by prefermentation skin contact for 4 days at 10°C and the lowest by the control and skin contact for 4 days at 15°C

Narratiwiteit en die Ou Testament

Narrativity in the Old TestamentThe epistemological status of the narrative as a mode of communication in the Old Testament is the issue in this article. It is argued that the narrative was deliberately chosen as a means of communication because ontologically it is a mode of existence, interpretation and familiarization. In the article the fiction-versus-fact debate is broadly discussed. A textual approach, in which the semiotic value of the specific structuring of the narrative discourse is adequately acknowledged, is put forward