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Hops (Humulus lupulus L.) are primarily used to provide specific characteristics to beer, such as bitterness, aroma, flavor, and microbial stability. The chemical composition of hops, relative to how they are used during the brewing process, dictates the expression of these characteristics. Of the raw ingredients that go into making beer, hops are perhaps the most costly. Considerable resources are required to grow quality hops, and therefore, brewers and hop growers alike have a common goal of obtaining the highest quality hops possible. However, quality can be a relative term. While it is commonly agreed upon that high brewing values, such as α-acids and essential oil content, and robust structural integrity are indicators of quality hops, there are many opinions of the ideal aroma. Changes in the chemical composition of hops during plant maturation are a dynamic process requiring a comprehensive, in-depth chemical and sensory analysis in order to maximize the characteristics of interest to brewers. The complex aroma chemistry associated with hops in beer has been a confounding variable for the practical brewer, and a deeper understanding of hop aroma development during cultivation is needed. The effect of harvest date, location, and cultivar on key chemical components of Willamette and Cascade hops was investigated for the 2010 and 2011 growing seasons. Hops were harvested at 3 time points (Early, Typical, and Late), within a 3-week interval from 2 different farms in the Willamette Valley, Oregon. A split-plot experimental design for each cultivar was used; each farm represented a main plot and harvest years were designated as subplots. American Society of Brewing Chemist standard methods of analysis were used to measure moisture content, hop acids and their homologs, Hop Storage Index, total essential oil content and volatile profile by GC-FID. Additionally, difference testing, descriptive analysis, and consumer acceptance testing was conducted using beers brewed with either Typical or Late harvested Cascade hops from the 2010 harvest year. The response of analytes was dependent on the cultivar being examined, its location within the Willamette Valley, as well as days until harvest. Hop acids did not change appreciably during plant maturation for the period examined, while hop oil content increased hyperbolically to a plateau as the hops aged on the bine. Increases in oil quantity were strongly correlated (r > 0.90) with increases in α-pinene, β-pinene, myrcene, limonene, methyl heptanoate, and linalool concentrations. For Cascade, α-pinene, β-pinene, myrcene, limonene, ρ-cymene, caryophyllene, E, β-farnesene, and humulene all increased from Early to Typical points but no increase was observed between the Typical and Late time point. Linalool and methyl heptanoate increased between each time point while citral and humulene epoxide differed between Early harvest and Late harvest, but not between Early and Typical or Late and Typical harvests. For Willamette hops, α-pinene, β-pinene, myrcene, limonene, ρ-cymene, and linalool all increased between each time point. Caryophyllene, E β-farnesene, humulene, farnesol and citral all increased from Early harvest to Typical harvest but no difference was observed between Typical and Late. Clear sensory differences were found between beers brewed with Typical harvest Cascade hops and Late harvest Cascade hops, in terms of difference testing, descriptive analysis and consumer preference tests. / Graduation date: 2013

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 70-78). Also available on the World Wide Web.

This thesis was written to document, through both primary and secondary sources, the history of hop growing as it was in Oregon between 1850 and 1950. In those years, hop growing was most often a speculative venture. Growers could be rich one year and bankrupt the next due to the uncertainties of marketing.

This work set out to examine the methodologies of dry hopping, compare different hop materials, and look at the extraction behavior of different types of hop compounds. This work consists of two discrete studies, where the first study informed the design of the second. The first study measured the concentrations of hop aroma compounds extracted from Cascade hops during dry hopping using a model beer system devoid of malt, yeast aromas, and hops. Cascade hops pelletized by four different processors yielded different particle size distributions and pellet densities. These pellets were dosed into a degassed medium (water, 6% v/v ethanol, pH 4.2) and the hop aroma extraction was measured periodically over a one week period. Solid phase micro-extraction (SPME) followed by gas chromatography (GC-FID) was used to analyze the levels of aroma compounds in the extraction medium. Variation in the hop pellet physical properties did not significantly impact the extraction rate of hop volatiles such as linalool, geraniol, limonene and myrcene with one exception. One treatment showed an increased absolute concentration of geraniol. Separately, dry hop aroma extraction was measured over a short time (1 day) at room temperature in an unhopped beer using small-scale (1L), stirred vessels. Irrespective of the hop form (whole or pellet), the concentrations of hydrocarbon terpenes peaked between 3 and 6 hours and subsequently declined, while the concentrations of terpene alcohols continued to increase throughout the 24 hour dry hop extraction. The rate of hop aroma extraction did not appear to be significantly influenced by hop pellet properties and occurred rather rapidly regardless of the hop form. The second study examined the extraction of hop aroma compounds during a pilot brewery scale (~4hL) dry hop treatment. Dry hop treatments consisted of whole cone hops and pellet hops (Cascade cultivar, 2011 harvest) which were dosed into cylindroconical vessels which were either stirred with a pump or left quiescent. Samples were taken for GC-FID and HPLC analysis as well as sensory evaluation at various time points between 30 minutes and 12 days. Polyphenol and alpha acid extraction was highest in a stirred system dosed with pellets. Hop aroma compound extraction was also the highest in the stirred system utilizing pellet hops. The sensory panel rated the stirred pellet samples as having the highest hop aroma, bitterness, and astringency. The results showed that hop flavor from dry hopping can be readily achieved with much shorter contact time than the current 4-12 day industry practice. / Graduation date: 2013

Hop cell wall material (CWM) extracted from hop leaves (hamulus lupulus) was purified and characterized. The total sugar content, uronic acid content and monosaccharide composition of the CWM were determined. Galacturonic acid is the major component in the CWM. A mixture of unsaturated oligogalacturonides were released from purified hop CWM by autoclaving. The biological activity of these oligomers was tested for their ability to elicit phytoalexins. The oligomer with hexagalacturonic acid possessed the greatest biological activity. Column chromatography and high-pH anion exchange chromatography were used for the sample separation and purification. Fast-atom-bombardment mass spectrometry (FAB-MS) was used for the structure elucidation. The FAB-MS spectrum showed that the unsaturated galacturonosyl residue was located at the nonreducing terminus of the oligomer. / Graduation date: 1993

Thesis (M.S.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 55-59). Also available on the World Wide Web.

The growth in the global data gathering capacity is producing a vast amount of data which is getting vaster at an increasingly faster rate. This data properly analyzed can represent great opportunity for businesses, but processing it is a resource-intensive task. Sharing can increase efficiency due to reusability but there are legal and ethical questions that arise when data is shared. The purpose of this thesis is to gain an in depth understanding of the different access control methods that can be used to facilitate sharing, and choose one to implement on a platform that lets user analyze, share, and collaborate on, datasets. The resulting platform uses a project based access control on the API level and a fine-grained role based access control on the file system to give full control over the shared data to the data owner. / I dagsläget så genereras och samlas det in oerhört stora mängder data som växer i ett allt högre tempo för varje dag som går. Den korrekt analyserade datan skulle kunna erbjuda stora möjligheter för företag men problemet är att det är väldigt resurskrävande att bearbeta. Att göra det möjligt för organisationer att dela med sig utav datan skulle effektivisera det hela tack vare återanvändandet av data men det dyker då upp olika frågor kring lagliga samt etiska aspekter när man delar dessa data. Syftet med denna rapport är att få en djupare förståelse för dom olika åtkomstmetoder som kan användas vid delning av data för att sedan kunna välja den metod som man ansett vara mest lämplig att använda sig utav i en plattform. Plattformen kommer att användas av användare som vill skapa projekt där man vill analysera, dela och arbeta med DataSets, vidare kommer plattformens säkerhet att implementeras med en projekt-baserad åtkomstkontroll på API nivå och detaljerad rollbaserad åtkomstkontroll på filsystemet för att ge dataägaren full kontroll över den data som delas

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Hops is a small, but important agricultural commodity in South Africa. The hop cones contain secondary metabolites responsible for the flavour, aroma and bitterness in beer. The George and Waboomskraal area are the best suited for growing hops due to climate and geographical location. The optimum latitude for hops growing is 45° - 54° north and south of the equator, while these areas are at 34° S. International hop varieties are not adapted to the South African climate. Winters are too warm and summer days too short, thus all the varieties grown in South Africa have been bred for these specific conditions. The Hop breeding and research program strives to develop internationally competitive varieties with higher yields, desirable brewing characteristics, reducing input costs and increased productivity. To evaluate the current agricultural practices and to determine whether some of these practices negatively affect the plant health and yield, a study was conducted to investigate the effect of the time of stripping. Stripping refers to the practice of removing basal growth of the lower laterals and untrained bines. The study was done in two different microclimates, namely George and Waboomskraal. The aim was to determine the effect of the time of stripping on the vegetative growth, light interception, biomass, soft resins (alpha and beta acids), yield, rootstock weights and carbohydrate concentrations. The effect of stripping was also evaluated on different planting systems and plant maturity, namely Tram lines and conventional planting and 3 years old versus 5 year old plants. The effect of early stripping in terms of dry weight on mature plants is considerably less than the effect on younger plants. Young plants delivered lower dry weights, but accumulated higher carbohydrate reserves in the early stripping treatment. On young plants early stripping showed a significant difference favouring yield on tramlines. There is a general trend across all sites of higher crop efficiencies in the early stripped treatments. Growers could significantly increase yields without negatively affecting the quality (alpha and beta acids) by applying early stripping, especially in the George area. The effect of early stripping becomes more apparent in consecutive years as the time of defoliation affects foliage, carbohydrate concentration, canopy microclimate and light interception resulting in increased yields, especially on tramlines. From this study it can be concluded that early stripping appeared to have an influence on the dry root weight, carbohydrate concentration, light interception, crop efficiencies, yield and biomass. This practice is not only environmentally friendly by using less herbicide, it also delivers an economic gain. The effect of the time of stripping in consecutive years and different varieties deserves further study. / AFRIKAANSE OPSOMMING: Hops is 'n klein, maar belangrike landbou kommoditeit in Suid-Afrika. Die hopkeëls bevat sekondêre metaboliete wat verantwoordelik is vir die smaak, aroma en bitterheid van bier. Die George en Waboomskraal gebied is die beste geskik vir die kweek van hops, a.g.v. die klimaat en geografiese ligging. Die optimum breedtegraad vir hops verbouing is tussen 45° - 54° noord en suid van die ewenaar, waar hierdie gebiede by 34° S lê. Internasionale hops varieteite is nie aangepas by die Suid-Afrikaanse klimaat nie, want die winters is te warm en die daglengte in die somer is te kort. Al die variëteite in Suid Afrika is geteel vir dié spesifieke klimaatstoestande. Die Hopsteling en -navorsingprogram streef daarna om internasionaal mededingende varieteite met hoër opbrengste, verminderde insetkoste, verhoogde produktiwiteit en wenslike broueienskappe te ontwikkel. 'n Studie is gedoen om die effek van stropingstyd te evalueer en te identifiseer of hierdie praktyk negatiewe invloede op die gesondheid van plante en opbrengste het. Stroping verwys na die praktyk van die verwydering van basale groei van die laer laterale en onopgeleide ranke. Die studie is gedoen in twee verskillende mikroklimate, naamlik George en Waboomskraal. Die doel was om te bepaal wat die effek van stropingstyd op die vegetatiewe groei, lig onderskepping, biomassa, alfasure en betasure, opbrengs, wortelmassa en koolhidrate konsentrasies is. Die effek van stropingstyd was ook geëvalueer op verskillende plantsisteme en plant volwassenheid, naamlik Tramlyne en Konvensionele -plantsisteem, en 3 jaar oue teenoor 5 jaar oue plante. Die effek van vroeë stroping in terme van droë gewig op volwasse plante is aansienlik minder as die effek op jonger plante. Jong plante het laer droë gewig, maar hoër koolhidraat reserwes in die vroeë stroping behandeling gelewer. Vroë stroping van jong plante het ’n beduidende verskil getoon ten opsigte van opbrengste op die Tramlyn-plantsisteem. Daar is 'n algemene tendens op alle lokaliteite van hoër opbrengs doeltreffendheid in die vroeë stropings behandelings. Produsente, veral in die George area, kan opbrengste aansienlik verhoog sonder om die kwaliteit (alfa en beta sure) negatief te beïnvloed, deur die toepassing van vroeë stroping. Die effek van vroeë stroping word meer duidelik in agtereenvolgende jare, omdat die stropingstyd die koolhidrate konsentrasie, mikroklimaat binne in die hopranke en lig onderskepping wat lei tot verhoogde opbrengste, veral op die Tramlyn- plantsisteem, beïnvloed. Uit hierdie studie kan afgelei word dat vroeë stroping 'n invloed op die ligonderskepping, plantgewas doeltreffendheid, biomassa, opbrengs, droë wortelgewig en koolhidraatkonsentrasie het. Hierdie praktyk is nie net omgewingsvriendelik nie, maar gebruik minder onkruiddoder en lewer ekononomiese voordele vir die produsent. Die effek van stropingstyd op agtereenvolgende jare en verskillende varieteite verdien verdere studie.

The Notch signalling pathway plays an essential role in cell-fate decisions and morphogenesis, and is frequently ectopically activated in human cancers. The signal is initiated through DSL ligand-dependent Notch proteolysis, which releases its intracellular domain. However, over-expression of the E3 ubiquitin ligase Deltex can bypass the requirement for Notch ligands and ectopically activate Notch by directing it into the endocytic pathway. It has been shown that Deltex induced endocytic-Notch signalling, but not DSL-induced signalling, requires both HOPS and AP-3 complex components that mediate trafficking to lysosomes and related organelles. I showed through a combination of the analysis of the dxsm mutant allele and by expression of mutant forms of Deltex in cell culture, that the C-terminal region of Deltex is important for Notch signalling, but is not required for Notch endocytosis. This suggests that the C-terminal region contains an interaction site that may direct endocytosed Notch to the correct endocytic compartment. A key question however was whether this endocytic pathway is utilised for full Notch signaling in normal development alongside the canonical activation mechanism. I therefore investigated the expression of Drosophila midline single-minded (sim), which is a Notch signal reporter gene, and embryonic neurogenesis which is repressed by Notch signalling. I found that deltex, HOPS and AP-3 mutants displayed gaps in sim expression and also a neurogenic phenotype similar to Notch loss-of-function, and consistent with a role for ligand-independent Notch activation in normal development. I found that the penetrance of these phenotypes increased when flies were cultured at higher temperature. These results suggest that Dx/HOPS/AP-3-dependent Notch activation provides a developmental robustness to the Notch signalling network. It was also found that AP-3 and HOPS components have an additional role in regulating cell survival, which is partially separable in time using a temperature shift assay. I also revealed a requirement of maternal Notch for cell survival in early embryonic development, which may be related to the HOPS-dependent function. Comparison of deltex, AP-3 and HOPS mutant phenotypes suggested that there may be functional redundancy of deltex with components that regulate Notch endocytosis, and of AP-3 with proteins that mediate subsequent trafficking to the late endosome/lysosome. Finally I characterised the molecular lesions of an allele of the HOPS component light and the AP-3 component ruby and identified lesions which were consistent with the loss-of-function of these genes.