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It has become apparent that beer (both alcoholic and nonalcoholic) contains appreciable amounts of non-starch polysaccharides, a broad subgroup of dietary fiber. It is worth noting that the occurrence of non-starch polysaccharides in alcoholic beer does not imply this should be consumed as a source of nutrition. But the popularity of nonalcoholic beer is growing, and the lessons learnt from non-starch polysaccharides in brewing can be largely translated to nonalcoholic beer. For context, we briefly review the origins of dietary fiber, its importance within the human diet and the significance of water-soluble dietary fiber in beverages. We review the relationship between non-starch polysaccharides and brewing, giving focus to the techniques used to quantify non-starch polysaccharides in beer, how they affect the physicochemical properties of beer and their influence on the brewing process. The content of non-starch polysaccharides in both regular and low/nonalcoholic beer ranges between 0.5 - 4.0 g/L and are predominantly composed of arabinoxylans and β-glucans. The process of malting, wort production and filtration significantly affect the soluble non-starch polysaccharide content in the final beer. Beer viscosity and turbidity are strongly associated with the content of non-starch polysaccharides.

The flexural bond strength of unreinforced masonry (URM) is a key material property affecting wall out-of-plane lateral load capacity. It is well known that the unit flexural bond strength (defined here as the flexural strength of the bond between the brick and lower mortar bed joint associated with any given masonry unit (brick)) varies considerably between units, and that this spatial variability might significantly affect the structural performance and reliability of URM walls in flexure. The paper develops a computational method to predict the strength for non-load bearing single skin URM walls subject to one-way vertical bending considering unit-to-unit spatial variability of flexural bond strength. We characterise the probability distributions of wall strength and examine how spatial variability in unit flexural bond strength affects the variability of base cracking load, mid-height cracking load, peak load and behaviour of clay brick URM walls. This is done using 3-D non-linear Finite Element Analyses (FEA) and stochastic analysis in the form of Monte Carlo simulations. Varying COVs (0.1, 0.3 and 0.5) of unit flexural bond strength are considered. The mean and variance of wall strength are estimated to show the effect of spatial variability of flexural bond strength on wall strength. The failure modes of the wall are compared to show the significant differences between non-spatial and spatial analyses.

Fermentation performance and final beer product quality can be greatly influenced by the integrity of brewing yeast mtDNA, particularly when petite mutants are formed. The factors that influence th...

Repeated reuse or “serial repitching” of yeast between successive fermentations exposes brewing yeast cells to a number of biological, chemical, and physical stresses. It is generally accepted that...

The aim of this study was to determine the transcriptomic response of Saccharomyces pastorianus to environmental change during brewery propagation. Utilization of amino acids and fermentable carboh...

Amino acid utilization by yeast during brewer's wort fermentation influences both the fermentation performance and flavor profile of the finished product. To better understand the relationship betw...

Brewery fermentations and handling of yeast populations between successive fermentations expose brewing yeast cells to a number of biological, chemical, and physical stresses. It is generally accep...

The paper summarises the results of a displacement-based assessment (DBA) of the seismic capacity of typical load-bearing unreinforced masonry buildings between two and five storeys in height across a range of site sub-soil classes (B to D) and earthquake hazard factors (0.05 to 0.12), covering all of the capital cities and major regional centres in Australia. The study found that the DBA for out-of-plane bending of walls in the top storey of buildings identified far fewer cases of failure than did a traditional strength-based assessment. A similar trend was observed for the DBA for in-plane shear of walls at the ground storey of buildings. The DBA implied, for all practical purposes, that typical walls will have the in-plane shear displacement capacity to withstand the earthquake induced loads and displacements for any site soil conditions, and earthquake hazard factor up to 0.12. This contrasts with the corresponding strength-based calculations, which identified significant numbers of cases where failure would occur.

After initial propagation, brewing yeast was predominantly exposed to CO2-induced anaerobic conditions during fermentation and storage. The transition from aerobiosis to anaerobiosis during ferment...

The paper examines the reliability of masonry walls designed for compression in accordance with AS3700. The results of a large number of tests on full-scale masonry walls in compression have been used to obtain probabilistic models of behaviour. Structural reliability was then estimated for vertical loading of unreinforced masonry walls loaded concentrically, considering variations of unit compressive strength, mortar type, tributary area and live-to-dead load ratios. A reliability-based calibration of the Australian masonry design code AS3700 was then conducted using a target reliability index specified in AS5104. Recommendations are made for changes to φ used for compression design in AS3700 that, if adopted, would lead to an increase of 66% in the design compressive strength of walls.

This paper examines the earthquake resistance of unreinforced masonry residential structures up to 15m in height, with a view to identifying the critical actions under a range of conditions. The study considers the wall forces and associated actions due to earthquake loads corresponding to the proposed revision of the Australian Standard for earthquake actions, AS 1170.4. The seismic demands under various conditions are compared with the corresponding seismic capacities given by the Australian Standard for masonry structures, AS 3700. A parametric study was used to examine the effects of a wide range of parameters, including number of storeys, wall geometries, support conditions and openings. The results of the parametric study indicate, for a typical office building and a typical home unit building, the range of conditions leading to earthquake failure using the current design criteria of AS 3700.

During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single yeast culture (slurry) over a number of fermentations (generations). Modern practices, such as the use of high-gravity worts and preparation of dried yeast for use as an inoculum, have increased the magnitude of the stresses to which the cell is subjected. The ability of yeast to respond effectively to these conditions is essential not only for beer production but also for maintaining the fermentation fitness of yeast for use in subsequent fermentations. During brewery handling, cells inhabit a complex environment and our understanding of stress responses under such conditions is limited. The advent of techniques capable of determining genomic and proteomic changes within the cell is likely vastly to improve our knowledge of yeast stress responses during industrial brewery handling.

For the production brewer, predicting fermentation performance may also involve the determination of the flocculation capacity of a given yeast slurry. Several methods have been reported, and a few...

Current unreinforced masonry design relies on limited models of flexural behaviour in the orthogonal and inclined directions, which are partly empirical and do not fully account for the beneficial ...

Non-ribosomal peptide synthetases, polyketides and fatty acid synthetases have a modular organisation of multi-enzymatic activities. In all of them, the acyl or peptidyl carrier proteins have 4'-phosphopantetheine (P-pant) as an essential prosthetic group. This is added by 4'-phosphopantetheinyl transferases (PPTases) that derive the P-pant group from coenzyme A. While many PPTases of varying specificity have now been isolated from a number of bacteria, a filamentous fungal PPTase has yet to be characterised. Through database searching of the Aspergillus fumigatus genome sequence against Sfp from Bacillus subtilis, we identified a unique sequence which appears to encode a PPTase, as deduced from conserved residues considered important in PPTases. The PPTase candidate was used to search the NCBI data base and an unexpected homologue in A. nidulans was identified as npgA. Mutations in this gene (cfwA/ npgA) were identified previously as leading to defects in growth and pigmentation. To test whether the temperature-sensitive cfwA2 mutation impairs penicillin biosynthesis, which is dependent on the delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase, bioassays with B. calidolactis were set up at permissive and non-permissive temperatures. The cfwA2 mutant did not produce penicillin at the non-permissive temperature. Since no other PPTase homologue has been detected in the A. fumigatus genome to date, the data suggest that a single enzyme may be able to transfer the cofactor to a broad range of enzymes with acyl or peptidyl carrier protein domains.

The fermentable carbohydrate composition of wort and the manner in which it is utilized by yeast during brewery fermentation have a direct influence on fermentation efficiency and quality of the final product. In this study the response of a brewing yeast strain to changes in wort fermentable carbohydrate concentration and composition during full-scale (3275 hl) brewery fermentation was investigated by measuring transcriptome changes with the aid of oligonucleotide-based DNA arrays. Up to 74% of the detectable genes showed a significant (p

Commercial brewing yeast strains are exposed to a number of potential stresses including oxidative stress. The aim of this investigation was to measure the physiological and transcriptional changes of yeast cells during full-scale industrial brewing processes with a view to determining the environmental factors influencing the cell's oxidative stress response. Cellular antioxidant levels and genome-wide transcriptional changes were monitored throughout an industrial propagation and fermentation. The greatest increase in cellular antioxidants and transcription of antioxidant-encoding genes occurred as the rapidly fermentable sugars glucose and fructose were depleted from the growth medium (wort) and the cell population entered the stationary phase. The data suggest that, contrary to expectation, the oxidative stress response is not influenced by changes in the dissolved oxygen concentration of wort but is initiated as part of a general stress response to growth-limiting conditions, even in the absence of oxygen. A mechanism is proposed to explain the changes in antioxidant response observed in yeast during anaerobic fermentation. The available data suggest that the yeast cell does not experience oxidative stress during industrial brewery handling. This information may be taken into consideration when setting parameters for industrial brewery fermentation.

During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single yeast culture (slurry) over a number of fermentations (generations). Modern practices, such as the use of high-gravity worts and preparation of dried yeast for use as an inoculum, have increased the magnitude of the stresses to which the cell is subjected. The ability of yeast to respond effectively to these conditions is essential not only for beer production but also for maintaining the fermentation fitness of yeast for use in subsequent fermentations. During brewery handling, cells inhabit a complex environment and our understanding of stress responses under such conditions is limited. The advent of techniques capable of determining genomic and proteomic changes within the cell is likely vastly to improve our knowledge of yeast stress responses during industrial brewery handling.

This report provides abridged information describing the most salient properties and biodegradation of 27 chlorinated volatile organic compounds detected during groundwater studies in the United States. This information is condensed from an extensive list of reports, papers, and literature published by the U.S. Government, various State governments, and peer-reviewed journals. The list includes literature reviews, compilations, and summaries describing volatile organic compounds in ground water. This report crossreferences common names and synonyms associated with volatile organic compounds with the naming conventions supported by the International Union of Pure and Applied Chemistry. In addition, the report describes basic physical characteristics of those compounds such as Henry’s Law constant, water solubility, density, octanol-water partition (log K ow ), and organic carbon partition (log K oc ) coefficients. Descriptions and illustrations are provided for natural and laboratory biodegradation rates, chemical by-products, and degradation pathways.

This report, a product of the National Water-Quality Assessment Program, is a compilation of physical data and biological data for algae, aquatic invertebrates, and fish collected in the Carson and Truckee River Basins, Nevada and California. Most of the data were collected between 1993 and 1996 at selected reaches on the Carson and Truckee Rivers. Algae and aquatic invertebrate samples were collected from cobble riffles, submerged woody-snag habitats, and from depositional areas such as pools. Between 1993 and 1996, fish and crayfish were collected from all wadeable habitats at each of seven basic-fixed sites using either electroshocking methods or seining. Additional fish and crayfish were collected at one site on the Truckee River in 1997. Fish were identified to species, measured for total and standard length, checked for anomalies, and weighed at the collection site. Fish were returned to the stream after measurements were taken. Measurements of water depth, stream velocity, determinations of substrate type and substrate embeddedness were made at each sampling site. Algae and aquatic invertebrate samples were sent to the U.S. Geological Survey National Water-Quality Laboratory for identification and enumeration. A total of 103 semi-quantitative and 55 qualitative algae samples were collected at 20 river reaches on the Carson and Truckee Rivers between 1993 and 1996. These samples represent algae in cobble riffles, on submerged woody snags, and on sediment surfaces in depositional areas. In those 158 samples, 514 algal species, varieties, or forms were identified. Of the 8 algal phyla represented, the diatoms (Phylum Bacillariophyta) were the most abundant with 351 species, varieties, or forms. The green algae (Phylum Chlorophyta) were next in abundance with 108 species, varieties, or forms followed by the blue-green algae (Phylum Cyanophyta) with 41 species, varieties, or forms.

The Carson River Basin is an area of dramatic contrasts. The Carson River drains pristine wilderness of the forested Sierra Nevada, which provides much of the basin's water. The chemical composition of the Carson River changes from that of a fresh, untamed white-water river in the Headwaters Area to that of stagnant saline sloughs and alkali lakes in the Carson Desert. The ground-water quality, particularly in shallow aquifers, broadly mirrors the chemical changes in the river-a major source of recharge to basin-fill aquifers. Contrasts in ground-water quality within the Carson River Basin are evident across the basin, among the different aquifers, and, to a lesser extent, between shallow ground water beneath urban and agricultural land. Using current drinking-water standards as a measure of overall water quality, ground-water quality in principal aquifers in the upper basin generally is good. Principal aquifers in the upper basin are a major source of supply for municipal systems that provide water to the communities of Minden, Gardnerville, and Carson City. Precipitation falling on the Sierra Nevada, along with recharge from the Carson River in areas of heavy ground-water pumping, is the major source of recharge to principal aquifers. Except for locally high concentrations of nitrate and presence of synthetic organic compounds, water quality in principal aquifers generally results from chemical reactions with aquifer materials. Some ground water in and adjacent to the Sierra Nevada contains uranium concentrations greater than the proposed drinking-water standard. Radon activities in the Sierra Nevada locally exceed 10,000 pCi/L and are highest in the Carson River Basin. Shallow aquifers in Carson Valley contain higher concentrations of most major constituents and, compared to water in principal aquifers, more commonly contain concentrations of some minor constituents that exceed drinking-water standards. Manganese exceeds the secondary maximum contaminant level at more than 25 percent of the sampled sites. Minor constituents that exceed drinking-water standards at less than 10 percent of sampled sites are arsenic, fluoride, nitrate, and iron. Water from shallow aquifers more commonly contains concentrations of arsenic, fluoride, iron, and manganese in excess of the drinking-water standards than does water from the principal aquifers. Shallow aquifers beneath the upper basin locally contain herbicides, pesticides, and volatile organic compounds. Beneath the urban part of Carson City, prometone, trichloroethylene, and tetrachloroethylene were found at concentrations well above the laboratory minimum reporting level. Trichloroethylene was found at concentrations above the drinking-water standard. With a few exceptions, ground water beneath agricultural land in Carson Valley contained, at most, low concentrations of synthetic organic compounds. Principal aquifers beneath the sparsely populated middle Carson River Basin are recharged by precipitation falling on the uplands and, locally, by the Carson River. Concentrations of major constituents in water from principal aquifers in the lower basin generally are higher than in water from the principal aquifers of the upper basin. Concentrations of dissolved solids, iron, manganese, and sulfate more commonly exceed drinking-water standards in principal aquifers of the middle than the upper basin.

Repeated reuse or “serial repitching” of yeast between successive fermentations exposes brewing yeast cells to a number of biological, chemical, and physical stresses. It is generally accepted that...

Oxidized nitrogen (nitrite + nitrate N) concentrations were measured from bulk precipitation, bulk through-fall, and streamflow in a 7.86 hectare forested watershed in southeastern Oklahoma during the wet season from March through June 1983. Oxidized nitrogen inputs comparable to results of other studies were recorded during the 19 rainstorms sampled. Oxidized nitrogen concentrations appeared to increase after rainfall interacted with the pine and hardwood canopies and were inversely related to both rainfall and through-fall depth. Oxidized N concentrations in streamflow were greatest during the rising limb of storm flow with subsequent decreases during the falling limb of storm hydrographs and lowest during base flow. The oxidized N inputs from bulk precipitation were considerably greater than outputs from streamflow resulting in a net retention of oxidized nitrogen within the watershed during the study period.