Signal conditioner circuit for photomultiplier tube

Miniaturized circuit improves measurement of radiation dose absorbed in a scintillation crystal. The temperature coefficient of the field-effect transistor gate-source voltage in the isolation amplifier can be readily controlled

Modeling the thermal behavior of biosphere 2 in a non-controlled environment using bond graphs

Biosphere 2 is a closed ecological system of high complexity built to deepen the understanding of ecological systems, to study the dynamics of closed ecologies, and to learn to control their behavior. The use of modeling and simulation is crucial in the achievement of these goals. Understanding a physical system is almost synonymous with possessing a model of its comportment. The main goal of this study is the development of a dynamic bond graph model that represents the thermal behavior of the complex ecological system under study, Biosphere 2. In this work, a first model that captures the behavior of the ecological system in a non-controlled environment is presented.Postprint (published version

Red wine quality and style: Diversities of composition and adverse influences from free SO2

Relationships between wine colour composition and the overall quality rating were investigated by analyses of 404 young red wines in two varietal classes from three successive vintages. The wines, of Shiraz and Cabernet Sauvignon from 20 viticultural regions of Australia, had been presented for comparative assessment at the Adelaide Wine Shows of 1974-75-76. There was a large variability in all aspects of phenolic content, in wine colour density and tint, in pH, and in levels of total SO2 and free SO2. The latter was the major influence on pigment equilibria, in which there was up to 10-fold variation in the degree of ionisation of anthocyanins (a). Positive quality factors were wine colour density, the parameter a, coloured anthocyanins, total pigments and total phenolics. Negative factors included colour tint, free SO2 and total SO2. There was no correlation with wine pH. Wide variation in winemaking practice concerning the amount and timing of SO2 additions is considered to have been responsible for much of the range in quality within these groups of wines.Qualität und Nuance von Rotwein: Schwankungen der Zusammensetzung sowie nachteiliger Einfluß von freiem SO2 Anhand der Analysen von 404 jungen Rotweinen - zwei Sorten aus drei aufeinanderfolgenden Jahrgängen - wurden die Beziehungen zwischen den Komponenten der Weinfärbung und der Gesamtnote der sensorischen Qualitätsprüfung untersucht. Die Weine, Shiraz und Cabernet Sauvignon, waren bei den Adelaide Wine Shows 1974/75/76 zur vergleichenden Beurteilung angestellt worden. Sämtliche Parameter des Phenolgehaltes, die Farbintensität und -tönung, der pH-Wert sowie der Gehalt an Gesamt-SO2 und freiem SO2 zeigten eine beträchtliche Variabilität. Das freie SO2 beeinflußte das Pigmentgleichgewicht am stärksten, wobei der Ionisationsgrad der Anthocyane (a) bis zu 10fach schwanken konnte. Positive Qualitätsfaktoren waren: Farbintensität, der Parameter a, gefärbte Anthocyane, Gesamtpigmente sowie Gesamtphenole. Zu den negativen Faktoren gehörten Farbtönung, freies SO2 und Gesamt-SO2. Keinerlei Korrelation bestand zum Wein-pH. Die unterschiedlichen Qualitätsnoten der geprüften Rotweine dürften zum Gutteil kellertechnisch, durch die beträchtlichen Schwankungen der zugesetzten SO2 -Mengen und des Behandlungszeitpunktes, bedingt sein

The effect of grapevine leafroll plus yellow speckle disease on annual growth, yield and quality of grapes from Cabernet Franc under two pruning systems

The effects of two combinations of grapevine leafroll plus yellow speckle disease in two high-yielding Sultana selections (H4 and H5) on the performance of Cabernet Franc under two pruning methods were determined over 6 years. When averaged over the 6 years, H5 and H4 reduced the weight of annual growth by 21%and15 %, decreased the yield of fresh fruit by 9 % and 6 %, and depressed the sugar concentration of juice by 0.6 and 0.3 °Brix respectively. The titratable acidity and the pH of juice were slightly affected in some years. The number of inflorescences and mean berry weight were not affected by either virus source. When compared with spur pruning and averaged over the 4 years, cane-pruned vines produced less annual growth (21 % ), progressively less fresh fruit (16 % ), and had lighter berries (9 % ), but effects on the numbers of inflorescences and sugar content were inconsistent between years; the acidity and pH of juice were not affected. Canepruned vines had obviously inferior and more variable fruit-set. However, no visible differences in fruit-set due to the virus sources within each pruning method were detected.There was evidence of a low incidence of natural spread of yellow speckle, but not of leafroll.Holzproduktion sowie Traubenertrag und -qualität von Cabernet Franc bei kombinierter Einwirkung von Leafroll und Yellow speckle disease in Verbindung mit zwei verschiedenen AnschnittsystemenZwei Kombinationen von Leafroll mit Yellow speckle disease wurden von den beiden ertragsstarken Sultana-Klonen H4 und H5 auf die Sorte Cabernet Franc, die auf Zapfen und auf Bogreben angeschnitten war, übertragen. Der Einfluß der Infektion auf die Leistungsfähigkeit dieser Sorte wurde über einen Zeitraum von 6 Jahren verfolgt. Im Durchschnitt der 6 Jahre war nach der Krankheitsübertragung von den Infektionsquellen H5 und H4 das Gewicht des jährlich produzierten Holzes um 21 bzw. 15 %, der Traubenertrag (Frischgewicht} um 9 bzw. 6 % und die Mostzuckerkonzentration um 0,6 bzw. 0,3 ° Bri.« verringert. In einigen Jahren waren auch die titrierbare Säure und das pH des Mostes leicht verändert. Die Anzahl der Infloreszenzen und das mittlere Beerengewicht wurden durch keine der beiden Viruskombinationen beeinflußt.Im Vergleich zu den auf Zapfen geschnittenen Reben zeigte Cabernet Franc bei Bogrebenschnitt im Mittel von 4 Jahren einen verringerten jährlichen Holzzuwachs (21 %), stetig abnehmenden Traubenertrag (16 %, bezogen auf Frischgewicht} und leichtere Beeren (9 %); die Anzahl der Infloreszenzen und der Zuckergehalt wurden durch den Anschnitt von Jahr zu Jahr uneinheitlich beeinflußt; ein Einfluß auf Säure und pH des Mostes lag nicht vor. Auf Bogen geschnittene Reben hatten einen deutlich erniedrigten und stärker schwankenden Beerenansatz. Innerhalb eines Schnittsystems wirkten sich die unterschiedlichen Virusherkünfte jedoch nicht merklich auf den Beerenansatz aus.Es wurde eine langsame natürliche Ausbreitung von Yellow speckle, aber nicht von Leafroll nachgewiesen

lnfluence of grape variety, climate and soil on grape composition and on the composition and quality of table wines

The influence of grape variety, soil type, climatic area and year of vintage on grape composition and wine quality was studied over a six-year period with three grape varieties in a eo-operative investigation. The wines were made under carefully controlled conditions to eliminate, as far as possible, any effect of winemaking technique. All viticultural and oenological treatments were replicated so that the data could be analysed statistically. When grapes from different viticultural areas were made into table wines, the quality of the wines was most closely related to grape variety, followed by climatic area and least of all by soil type.Reproducible differences in grape and wine composition were found for the grape varieties studied. For fhe same sugar content Riesling grapes and wine contained more acidity and a higher tartaric acid/malic acid ratio than Clare Riesling grapes and wine. They also contained less nitrogen, phosphorus and potassium. Shiraz grapes were relatively high in malic acid.The year of vintage strongly influenced the tartaric acid/malic acid ratio, particularly for Riesling and Clare Riesling, and also certain other constituents. Certain years could be designated as either high or low malic acid years for a particular grape variety.The soil type influenced the amounts of certain of the constituents of grapes and wine, but had no significant effects on the wine quality. Wines from the same varieties grown on two widely different soils in the same area could not be differentiated in replicated taste tests. The soil depth, drainage and waterholding capacity appeared to be more important than composition per se.Wines made from irrigated vineyards in the warm River Murray viticultural region, contained similar amounts of tartaric and malic acids, but were higher in pH, than wines made from the same grape varieties in the cooler non-irrigated Barossa Valley. Wines from irrigated grapes were generally of somewhat lower quality than those made from grapes of the same variety grown without irrigation in a cooler area. The time of harvesting irrigated grapes appeared to be critical to achieve the necessary balance between sugar, acid and flavour. Shiraz grapes grown under irrigation contained considerably less colour than grapes of the same variety grown without irrigation.Aroma was correlated with flavour in assessing wine quality, but numerical values ascribed to these parameters did not correlate generally with the wine constituents measured. A positive correlation existed between high tasting scores and high Ball/acid ratio

Enhanced equal frequency partition method for the identification of a water demand system

This paper deals with unsupervised partitioning. A first goal of this paper is to present an enhancement to the Equal Frequency Partition (EFP) method that allows to reduce, to some extent, the main drawback of this classical classification method, i.e. the data distribution dependency. A second goal of this work is to use the Enhanced Equal Frequency Partition (EEFP) method within the discretization process of the Fuzzy Inductive Reasoning (FIR) methodology for the identification of a model of a water demand system. It is shown that use of the EEFP method allows to obtain more accurate FIR models of the water demand system, reducing the prediction errors.Peer ReviewedPostprint (author's final draft

SURFATM-NH3: a model combining the surface energy balance and bi-directional exchanges of ammonia applied at the field scale

A new biophysical model SURFATM-NH3, simulating the ammonia (NH<sub>3</sub>) exchange between terrestrial ecosystems and the atmosphere is presented. SURFATM-NH3 consists of two coupled models: (i) an energy budget model and (ii) a pollutant exchange model, which distinguish the soil and plant exchange processes. The model describes the exchanges in terms of adsorption to leaf cuticles and bi-directional transport through leaf stomata and soil. The results of the model are compared with the flux measurements over grassland during the GRAMINAE Integrated Experiment at Braunschweig, Germany. The dataset of GRAMINAE allows the model to be tested in various meteorological and agronomic conditions: prior to cutting, after cutting and then after the application of mineral fertilizer. The whole comparison shows close agreement between model and measurements for energy budget and ammonia fluxes. The major controls on the ground and plant emission potential are the physicochemical parameters for liquid-gas exchanges which are integrated in the compensation points for live leaves, litter and the soil surface. Modelled fluxes are highly sensitive to soil and plant surface temperatures, highlighting the importance of accurate estimates of these terms. The model suggests that the net flux depends not only on the foliar (stomatal) compensation point but also that of leaf litter. SURFATM-NH3 represents a comprehensive approach to studying pollutant exchanges and its link with plant and soil functioning. It also provides a simplified generalised approach (SVAT model) applicable for atmospheric transport models

Synthesis and evaluation of novel 7- and 8-aminophenoxazinones for the detection of β-alanine aminopeptidase activity and the rapid identification of Pseudomonas aeruginosa in clinical samples

A series of novel 8-aminophenoxazin-3-one and 7-aminophenoxazin-3-one chromogens and their corresponding β-alanine derivatives were synthesized and evaluated for their ability to detect β-alanyl aminopeptidase activity in bacteria known to hydrolyse β-alanine derivatized substrates. The results provided insight into the structural requirements for effective visualization of enzymatic activity and the mechanism of formation of phenoxazinon-3-ones. 8-Aminophenoxazin-3-one substrates 23c, 23d and 23e were prepared in good to high overall yield and were selective for β-alanyl aminopeptidase activity in bacteria, producing a lighter agar background coloration facilitating visualization of colored colonies, with variable localization to the colonies, but had lower sensitivities for the detection of Pseudomonas aeruginosa in comparison to the analogous 7-aminophenoxazin-3-one substrates. The synthetic methodology employed here allows the preparation of a range of substrates for evaluation and the establishment of structure-activity relationships. For example, the 2-pentyl substituted aminophenoxazin-3-one 22b performed with analogous sensitivity to the corresponding 1-pentyl-7-aminophenoxazin-3-one substrate 1 used commercially, highlighting that the position of the pentyl substituent can be varied while maintaining detection sensitivity