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The burgeoning interest in archaic, traditional, and novel beer styles has coincided with a growing appreciation of the role of yeasts in determining beer character as well as a better understanding of the ecology and biogeography of yeasts. Multiple studies in recent years have highlighted the potential of wild Saccharomyces and non‐Saccharomyces yeasts for production of beers with novel flavour profiles and other desirable properties. Yeasts isolated from spontaneously fermented beers as well as from other food systems (wine, bread, and kombucha) have shown promise for brewing application, and there is evidence that such cross‐system transfers have occurred naturally in the past. We review here the available literature pertaining to the use of nonconventional yeasts in brewing, with a focus on the origins of these yeasts, including methods of isolation. Practical aspects of utilizing nondomesticated yeasts are discussed, and modern methods to facilitate discovery of yeasts with brewing potential are highlighted.

Purpose: To solve complex health issues, an innovative and multidisciplinary framework is necessary. The Clinical Public Health (CPH) Division was established at the University of Toronto (UofT), Canada to foster inte-gration of primary care, preventive medicine and public health in education, practice and research. To better understand how the construct of CPH might be applied, we surveyed clinicians, researchers and public health professionals affiliated with the CPH Division to assess their understanding of the CPH concept and its utility in fostering broad collaboration. Methods: A two-wave anonymous survey of the active faculty of the CPH Division, UofT was conducted across Canada. Wave 1 participants (n = 187; 2016) were asked to define CPH, while Wave 2 participants (n = 192; 2017) were provided a synthesis of Wave 1 results and asked to rank each definition. Both waves were asked about the need for a common definition, and to comment on CPH. Results: Response rates for the first and second waves were 25% and 22%, respectively. Of the six definitions of CPH from Wave 1, “the intersection of clinical practice and public health,” was most highly ranked by Wave 2 participants. Positive perceptions of CPH included multidisciplinary collaboration, new fields and insights, forward thinking and innovation. Negative perceptions included CPH being a confusing term, too narrow in scope or too clinical. Conclusion: The concept of Clinical Public Health can foster multidisciplinary collaboration to address com-plex health issues because it provides a useful framework for bringing together key disciplines and diverse professional specialties.

Purpose: To solve complex health issues, an innovative and multidisciplinary framework is necessary. The Clinical Public Health (CPH) Division was established at the University of Toronto (UofT), Canada to foster inte-gration of primary care, preventive medicine and public health in education, practice and research. To better understand how the construct of CPH might be applied, we surveyed clinicians, researchers and public health professionals affiliated with the CPH Division to assess their understanding of the CPH concept and its utility in fostering broad collaboration. Methods: A two-wave anonymous survey of the active faculty of the CPH Division, UofT was conducted across Canada. Wave 1 participants (n = 187; 2016) were asked to define CPH, while Wave 2 participants (n = 192; 2017) were provided a synthesis of Wave 1 results and asked to rank each definition. Both waves were asked about the need for a common definition, and to comment on CPH. Results: Response rates for the first and second waves were 25% and 22%, respectively. Of the six definitions of CPH from Wave 1, “the intersection of clinical practice and public health,” was most highly ranked by Wave 2 participants. Positive perceptions of CPH included multidisciplinary collaboration, new fields and insights, forward thinking and innovation. Negative perceptions included CPH being a confusing term, too narrow in scope or too clinical. Conclusion: The concept of Clinical Public Health can foster multidisciplinary collaboration to address com-plex health issues because it provides a useful framework for bringing together key disciplines and diverse professional specialties.

Purpose: To solve complex health issues, an innovative and multidisciplinary framework is necessary. The Clinical Public Health (CPH) Division was established at the University of Toronto (UofT), Canada to foster inte-gration of primary care, preventive medicine and public health in education, practice and research. To better understand how the construct of CPH might be applied, we surveyed clinicians, researchers and public health professionals affiliated with the CPH Division to assess their understanding of the CPH concept and its utility in fostering broad collaboration. Methods: A two-wave anonymous survey of the active faculty of the CPH Division, UofT was conducted across Canada. Wave 1 participants (n = 187; 2016) were asked to define CPH, while Wave 2 participants (n = 192; 2017) were provided a synthesis of Wave 1 results and asked to rank each definition. Both waves were asked about the need for a common definition, and to comment on CPH. Results: Response rates for the first and second waves were 25% and 22%, respectively. Of the six definitions of CPH from Wave 1, “the intersection of clinical practice and public health,” was most highly ranked by Wave 2 participants. Positive perceptions of CPH included multidisciplinary collaboration, new fields and insights, forward thinking and innovation. Negative perceptions included CPH being a confusing term, too narrow in scope or too clinical. Conclusion: The concept of Clinical Public Health can foster multidisciplinary collaboration to address com-plex health issues because it provides a useful framework for bringing together key disciplines and diverse professional specialties.

The potential of yeasts isolated from traditional chichas as starter cultures, either for controlled production of the native beverage or for industrial beer production, has been investigated. Three S. cerevisiae strains and one T. delbrueckii strain isolated from four different Ecuadorian chichas were compared to ale and lager beer strains with respect to fermentation performance, sugar utilisation, phenolic off-flavour production, flocculation and growth at low temperature. Fermentations were performed in 15 °P all-malt wort and in a model chicha substrate at 12 °C and 20 °C. Tall-tube fermentations (1.5 L) were also performed with both substrates to assess yeast performance and beer quality. Among the strains tested, only one Ecuadorian S. cerevisiae strain was able to ferment the wort sugars maltose and maltotriose. Fermentations with all Ecuadorian strains were poor in wort at 12 °C relative to 20 °C, but were similar in model chicha substrate at both temperatures. The aromatic profile was different between species and strains. These results indicate the potential of yeasts derived from traditional Andean fermented beverages for commercial applications. One of the chicha strains demonstrated traits typical of domesticated brewery strains and could be suitable for ale fermentation, while the other strains may have potential for low-alcohol beer or chicha production.

The utilization of S. eubayanus has recently become a topic of interest due to the novel organoleptic properties imparted to beer. However, the utilization of S. eubayanus in brewing requires the comprehension of the mechanisms that underlie fermentative differences generated from its natural genetic variability. Here, we evaluated fermentation performance and volatile compound production in ten genetically distinct S. eubayanus strains in a brewing fermentative context. The evaluated strains showed a broad phenotypic spectrum, some of them exhibiting a high fermentation capacity and high levels of volatile esters and/or higher alcohols. Subsequently, we obtained molecular profiles by generating ‘end‐to‐end’ genome assemblies, as well as metabolome and transcriptome profiling of two Patagonian isolates exhibiting significant differences in beer aroma profiles. These strains showed clear differences in concentrations of intracellular metabolites, including amino acids, such as valine, leucine and isoleucine, likely impacting the production of 2‐methylpropanol and 3‐methylbutanol. These differences in the production of volatile compounds are attributed to gene expression variation, where the most profound differentiation is attributed to genes involved in assimilatory sulfate reduction, which in turn validates phenotypic differences in H2S production. This study lays a solid foundation for future research to improve fermentation performance and select strains for new lager styles based on aroma and metabolic profiles.

The work in this thesis aims to uncover energy loss mechanisms in MEMS-based piezoelectric contour-mode resonators. Quality factors for these devices has been constrained to under 10,000, limiting their commercial applications. The first part of this thesis studies Q degredation related to anchor losses. During fabrication, the outer edge of the anchors are released from the substrate due to an isotropic etch step used in releasing the device from the substrate. This allows both ends of the anchors and the surrounding region of the device layers to undergo strain resulting in energy loss during operation. This study finds that a variation in Q of up to 31% can occur as a result of this released area. A novel method for minimizing this loss through modified boundary conditions is also analyzed and experimentally tested.\par The second part of this thesis develops a new method of measuring ring-downs at ultra high frequencies using laser Doppler vibrometry. Due to an inherently low signal to noise ratio and a 4ns timing error in the vibrometer measurement triggering, traditional ring-down methods are not possible at ultra high frequencies. The method outlined here overcomes this and produces results with an error of less than 6% when compared to electrically determined values.Next, a method is outlined for measuring the magnitudes of the individual material wavelengths on the surface of the resonator. The devices are composed of multiple material layers, each with a unique acoustic velocity. As a result, at resonance, each layer has a unique wavelength that can be measured using laser Doppler vibrometery.The final section combines the previous two methods to measure the ring-downs of the individual material layers used in the construction of the resonators. Due to their unique material properties, the rate at which the vibrations of each material decays can be quantified to determine future fabrication choices.

The work in this thesis aims to uncover energy loss mechanisms in MEMS-based piezoelectric contour-mode resonators. Quality factors for these devices has been constrained to under 10,000, limiting their commercial applications. The first part of this thesis studies Q degredation related to anchor losses. During fabrication, the outer edge of the anchors are released from the substrate due to an isotropic etch step used in releasing the device from the substrate. This allows both ends of the anchors and the surrounding region of the device layers to undergo strain resulting in energy loss during operation. This study finds that a variation in Q of up to 31% can occur as a result of this released area. A novel method for minimizing this loss through modified boundary conditions is also analyzed and experimentally tested.\par The second part of this thesis develops a new method of measuring ring-downs at ultra high frequencies using laser Doppler vibrometry. Due to an inherently low signal to noise ratio and a 4ns timing error in the vibrometer measurement triggering, traditional ring-down methods are not possible at ultra high frequencies. The method outlined here overcomes this and produces results with an error of less than 6% when compared to electrically determined values.Next, a method is outlined for measuring the magnitudes of the individual material wavelengths on the surface of the resonator. The devices are composed of multiple material layers, each with a unique acoustic velocity. As a result, at resonance, each layer has a unique wavelength that can be measured using laser Doppler vibrometery.The final section combines the previous two methods to measure the ring-downs of the individual material layers used in the construction of the resonators. Due to their unique material properties, the rate at which the vibrations of each material decays can be quantified to determine future fabrication choices.

Recent studies found a disproportionate number of converts to Islam taking part in radical activities as opposed to those born into the faith. While research linking conversion to radicalization is available, a gap exists in research examining what in the conversion process is causing this phenomenon. This thesis asks, what is the relationship between religious conversion and violent extremism? This study explores 38 individuals who converted to Islam and subsequently committed a radical act. The thesis investigates four hypotheses concerning sociological and psychological factors driving religious conversion. These driving factors are a lack of secure attachments, interpersonal connections, significant personal problems, and individuals with perceived grievances being targeted by recruiters. The most significant driving factor in radicalization was individuals who had significant personal problems in their lives leading up to conversion, especially if a previous connection to a radical milieu existed. Recruiters seeking targets of opportunity among aggrieved individuals to convert was not a significant driving factor. Religious conversion by itself should not raise red flags, but conversion with other underlying factors indicates a greater risk for radicalization. The underlying factors are the drivers of radicalization, and the conversion gives individuals a reason to manifest their radical tendencies.

Maintaining stable flavor profile in beer is crucial after the beer is stored. The storage conditions may vary greatly inducing loss of flavors and formation of undesired compounds. Yeast is a key component in brewing and potentially contributes to the flavor stability of the beer. Maintaining the yeast viable throughout the brewing process prevents the formation of off-flavors via cell lysis and/or metabolic activity. The major contributor to cellular age under non-dividing state is the accumulation of reactive oxygen species (ROS), often referred to as The Free radical theory of ageing. The major source of ROS is the mitochondria and without a sufficient antioxidant system, these radicals can cause cellular damage. The purpose of this work was to study whether increasing yeast’s resistance to oxidative stress influences its longevity. A technique called adaptive evolution was applied to one bottom-fermenting (lager) and one top-fermenting (ale) brewing yeast strain, A15 and A224, respectively, to improve their resistance against oxidants. The yeast was adapted in seven different media including YPM and YPM supplemented with acrolein, ethanol, CuSO4, H2O2, menadione and paraquat for approximately 150 cell generations. Isolated adapted variants were then screened for resistance to these oxidants. A copper-adapted variant of A15 was found and it was shown to restrict the uptake of the metal. The original strain on the other hand accumulated quickly toxic amounts of copper. The adapted strain was also more sensitive to ethanol and grew slower in control conditions compared to the parent strain suggesting its growth is copper-limited. The copper-adapted strain was also more sensitive to chronological ageing, revealed by the longevity experiment carried out in this work. Antioxidant analyses executed during the ageing experiments revealed that the non-enzymatic antioxidant glutathione is the first to appear and be depleted during storage in beer, but not in water. The a, Oluen makuyhdisteiden säilyvyys on elintärkeää lopputuotteessa, mutta vaihtelevat varastointiolosuhteet hankaloittavat makujen pysyvyyttä. Hiiva on yksi oluen tärkeimmistä raaka-aineista, joka tuottaa olueen maku- ja aromiyhdisteitä. Toisaalta hiivalla on mahdollisesti tärkeä rooli maun stabiiliuden kannalta, minkä vuoksi hiivan säilyvyyden parantaminen saattaa ehkäistä oluen sivumakujen muodostumista soluhajoamisen ja/tai eri metaboliareittien kautta. Solujen ikääntymisen on arveltu johtuvan reaktiivisten happiyhdisteiden kerääntymisestä, mikä saattaa aiheuttaa solunsisäisiä vaurioita ilman riittävää antioksidanttista puolustusmekanismia. Tämä teoria tunnetaan myös nimellä Vapaiden radikaalien ikääntymisteoria (eng. Free radical theory of ageing). Pääasiallinen happiradikaalien lähde on mitokondrio. Tämän työn tarkoitus oli tutkia, vaikuttaako hiivan oksidatiivisen stressin sietokyvyn lisääminen ikääntymiseen. Kahden panimohiivakannan, A15 ja A224, sietokykyä pyrittiin lisäämään adaptiivisella evoluutiolla, jossa hiivaa kasvatettiin seitsemällä eri liemellä sisältäen YPM-alustan sekä YPMliemen, johon oli lisätty akroleiinia, etanolia, kuparisulfaattia, vetyperoksidia, menadionia tai paraquatia noin 150 solujakautumisen ajan. Adaptiivisen evoluution jälkeen eristettyjen hiivavarianttien vastustuskyky mainittuja oksidantteja vastaan tutkittiin tehoseulonnan avulla. Tutkimuksessa löydettiin kupariresistentti variantti A15-hiivasta, jonka havaittiin jatkotutkimuksissa estävän kuparin virtauksen solun sisälle, kun taas alkuperäinen kanta akkumuloi nopeasti haitallisen määrän kuparia. Kupariadaptoituneen kannan havaittiin olevan myös herkkä etanolille ja kasvoi isäntäkantaa hitaammin kontrolliolosuhteissa, minkä todettiin viittaavaan kuparirajoitteeseen kasvuun. Ikääntymiskokeissa tämän kannan havaittiin kestävän varastointia huonommin. Ikääntymiskokeiden yhteydessä solujen antioksidanttien, glutationin, superoksidi dismutaasin ja katalaasien, pitoisuudet määritettiin. E

The lager brewing yeast Saccharomyces pastorianus, an interspecies hybrid of S. eubayanus and S. cerevisiae, ferments maltotriose, maltose, sucrose, glucose and fructose in wort to ethanol and carbon dioxide. Complete and timely conversion ("attenuation") of maltotriose by industrial S. pastorianus strains is a key requirement for process intensification. This study explores a new evolutionary engineering strategy for improving maltotriose fermentation kinetics. Prolonged carbon-limited, anaerobic chemostat cultivation of the reference strain S. pastorianus CBS1483 on a maltotriose-enriched sugar mixture was used to select for spontaneous mutants with improved affinity for maltotriose. Evolved populations exhibited an up to 5-fold lower residual maltotriose concentration and a higher ethanol concentration than the parental strain. Uptake studies with 14C-labeled sugars revealed an up to 4.75-fold higher transport capacity for maltotriose in evolved strains. In laboratory batch cultures on wort, evolved strains showed improved attenuation and higher ethanol concentrations. These improvements were also observed in pilot fermentations at 1,000-L scale with high-gravity wort. Although the evolved strain exhibited multiple chromosomal copy number changes, analysis of beer made from pilot fermentations showed no negative effects on flavor compound profiles. These results demonstrate the potential of evolutionary engineering for strain improvement of hybrid, alloploid brewing strains., BT/Industrial Microbiology

The lager brewing yeast Saccharomyces pastorianus, an interspecies hybrid of S. eubayanus and S. cerevisiae, ferments maltotriose, maltose, sucrose, glucose and fructose in wort to ethanol and carbon dioxide. Complete and timely conversion ("attenuation") of maltotriose by industrial S. pastorianus strains is a key requirement for process intensification. This study explores a new evolutionary engineering strategy for improving maltotriose fermentation kinetics. Prolonged carbon-limited, anaerobic chemostat cultivation of the reference strain S. pastorianus CBS1483 on a maltotriose-enriched sugar mixture was used to select for spontaneous mutants with improved affinity for maltotriose. Evolved populations exhibited an up to 5-fold lower residual maltotriose concentration and a higher ethanol concentration than the parental strain. Uptake studies with 14C-labeled sugars revealed an up to 4.75-fold higher transport capacity for maltotriose in evolved strains. In laboratory batch cultures on wort, evolved strains showed improved attenuation and higher ethanol concentrations. These improvements were also observed in pilot fermentations at 1,000-L scale with high-gravity wort. Although the evolved strain exhibited multiple chromosomal copy number changes, analysis of beer made from pilot fermentations showed no negative effects on flavor compound profiles. These results demonstrate the potential of evolutionary engineering for strain improvement of hybrid, alloploid brewing strains., BT/Industriele Microbiologie

The use of immobilized cell technology (ICT) is viewed as a promising biotechnological tool to achieve high volumetric productivities of yeast fermentation in bioindustry of alcoholic beverages. During this process a huge number of organic compounds are being formed as yeast secondary metabolites, among which volatile compounds, such as higher alcohols, esters, and vicinal diketones, are the most important flavoring compounds. The objective of this chapter is to summarize the knowledge on the origin of the flavor-active and nonvolatile compounds synthesized by yeast and to describe how the composition of the medium, culture strain, process conditions (temperature, aeration, etc.), bioreactor design, and other critical parameters influence the metabolic activities of yeast cultures. Despite the technological and economic advantages provided by ICT, commercialization of this technology experienced only limited success, mainly due to unpredictable effect of immobilization on yeast physiology. This chapter is an attempt to rationalize and make some conclusions about the impact of cell immobilization on yeast metabolism collected from empirical experiences in production of alcoholic beverages. The knowledge addressing this issue may be of particular benefit to the nascent bioflavor industry.

Controlling beer flavour stability is of high importance to brewers because of export and extended storage of packaged beer. Antioxidant (AO) capacity has been claimed to be a major factor affecting the rate of beer staling. However, there is no consensus in the literature on the relative significance of oxidative vs. non-oxidative staling in beer packaged using modern methods enabling low oxygen concentrations (50-450 ppb) in the package. The current thesis aimed to investigate the relationship between AO capacity and beer staling by measuring the AO capacity and monitoring aldehyde formation in 35 commercial beers from Finnish breweries. Staling was evaluated by monitoring the formation of 6 aldehyde compounds by gas chromatography. Principal component analysis and partial least squares regression were used to search for correlations in the data. In order to evaluate the effect of the yeast on the AO capacity and ageing of beer, 0,1 ml – 1,5 l scale fermentations were conducted with top and bottom fermenting industrial brewing yeast strains as well as strains from VTT culture collection. PCA analysis revealed a positive correlation between the AO capacity and the apparent extract of the commercial beers. A positive correlation was found between the metal-chelation ability and the bitterness of the beer. No significant correlation between AO capacity and staling of the commercial beers was discovered. The relationship between the two factors suggested by previous research may have been obscured by varying oxygen, aldehyde precursor and amino acid concentrations, as well as differences in the manufacturing process between breweries. The fermentations in 100 ml volume using two different commercial lager yeast strains resulted in significant differences in the AO capacity of the beers. In an ageing test, a beer with lower AO capacity showed a two to sixfold larger increase in each aldehyde concentration. This suggested a relationship between AO capacity and beer stal, Oluen maun säilyvyyden hallinta säilytyksen ja kuljetuksen aikana on tärkeää panimoille. Antioksidanttikapasiteetin (AO-kapasiteetin) on katsottu olevan tärkeä tekijä oluen maun säilyvyydelle. Aiemmat tutkimukset eivät kuitenkaan ole yksimielisiä siitä, miten tärkeitä hapettumisreaktiot ovat oluen pilaantumiselle ei-oksidatiivisiin reaktioihin verrattuna modernissa pakatussa oluessa, jonka happipitoisuus on hyvin alhainen (50 – 450 ppb). Tässä diplomityössä tutkittiin antioksidanttikapasiteetin ja oluen pilaantumisen välistä yhteyttä mittaamalla 35 suomalaisten panimoiden tuottaman kaupallisen oluen AO-kapasiteetti ja seuraamalla kuuden eri aldehydin muodostumista oluissa vanhennuskokeissa kaasukromatografian avulla. Mittaustuloksista etsittiin riippuvuussuhteita pääkomponenttianalyysin ja pienimmän neliösumman menetelmän avulla. Hiivan vaikutusta arvioitiin 0,1 – 1,5 l koefermentointien avulla. Fermentoinneissa käytettiin sekä panimoilta saatuja hiivakantoja että VTT:n kantakokoelman panimohiivakantoja. Pääkomponenttianalyysin avulla löydettiin positiivinen riippuvuus AO-kapasiteetin ja näennäisen uutepitoisuuden välillä, sekä metallikelaatiokyvyn ja katkeruuden välillä. Merkittävää riippuvuutta AO-kapasiteetin ja kaupallisten oluiden vanhenemisen välillä ei löydetty. Tulokset viittaavat siihen, että vaihtelevat tuotanto- ja pullotusolosuhteet, sekä vaihtelevat pilaantumisreaktioiden lähtöainepitoisuudet luultavasti estivät aiempien tutkimustulosten kaltaisen riippuvuuden löytymisen. Kahden kaupallisen lagerhiivan koefermentointien tuloksena saatiin kaksi AO-kapasiteetiltään hyvin erilaista olutta. Vanhennuskokeissa eri aldehydien konsentraatiot kasvoivat kahdesta kuusinkertaisesti oluessa jolla oli näistä kahdesta pienempi antioksidanttikapasiteetti. Tulos viittaa riippuvuuteen samalla tavoin valmistettujen oluiden AO-kapasiteetin ja vanhenemisen välillä. 1,5 l fermentoinneissa havaittiin pienempää vaihtelua AO-kapasiteetissa kuin 100 ml mittakaavassa. Seurattaess

The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 degrees C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212.

The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 degrees C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212.

Immobilized cell technology has shown a significant promotional effect on the fermentation of alcoholic beverages such as beer, wine and cider. However, genetic, morphological and physiological alterations occurring in immobilized yeast cells impact on aroma formation during fermentation processes. The focus of this review is exploitation of existing knowledge on the biochemistry and the biological role of flavour production in yeast for the biotechnological production of aroma compounds of industrial importance, by means of immobilized yeast. Various types of carrier materials and immobilization methods proposed for application in beer, wine, fruit wine, cider and mead production are presented. Engineering aspects with special emphasis on immobilized cell bioreactor design, operation and scale-up potential are also discussed. Ultimately, examples of products with improved quality properties within the alcoholic beverages are addressed, together with identification and description of the future perspectives and scope for cell immobilization in fermentation processes.

Diacetyl and 2,3-pentanedione are butter-tasting vicinal diketones produced as by-products of valine and isoleucine biosynthesis during wort fermentation, and their presence in beer is usually unwanted. Yeast are able to reduce diacetyl and 2,3-pentanedione into compounds with higher flavour thresholds, and this is usually achieved during a resource-and time-consuming maturation phase after the primary fermentation. One promising method of decreasing diacetyl production during fermentation is through the control of the valine content of the wort, since valine is involved with the feedback inhibition of enzymes controlling the valine biosynthesis pathway and indirectly the formation of diacetyl precursors. The objective of this thesis was to investigate the influence of valine supplementation, wort amino acid profile and free amino nitrogen content on diacetyl formation during wort fermentation with the lager yeast Saccharomyces pastorianus, by carrying out a series of small-scale (2-litre) and medium-scale (10-litre) fermentations, which were sampled and analysed for diacetyl and amino acid concentrations, along with standard beer parameters. Supplementation of valine to the wort resulted in decreased maximum (up to 37% lower) and final (up to 33% lower) diacetyl concentrations in all trials, and the composition of the amino acid spectrum of the wort also had an impact on diacetyl and 2,3-pentanedione production during fermentation. The results suggest that there is no correlation between the concentrations of wort amino acids and diacetyl production per se, but rather a negative correlation between the uptake rate of valine (and also other branched-chain amino acids) and diacetyl production was found. The results from all four experiments agree that fermentation performance and yeast growth was not affected by the studied levels of amino acid supplementations, implying that supplementation of valine or other amino acids will not affect the fermentation time nor the

The future security environment is poised to become even more difficult for strategic leaders to navigate, exposing national security policy to an increasingly global and interconnected audience. Advancing technologies, further interconnecting international systems and increasing and faster media access will immediately display the civil-military discourse and its impact on the national security apparatus. The past ten years has highlighted strategic gaps in that discourse, leading to significant damage to individuals, organizations, and institutions. Strategic leaders, civilian and military alike, share responsibility to uphold the highest ideals in conducting future discourse, emphasizing ethical, and professional, decision making. there is likely no more difficult calling for a military professional than to dissent, especially when there are clear moral, legal, or ethical reasons to do so. It is when those reasons blur in a world increasingly turning grey where our future civil-military discourse demands strategic military leaders to fully understand dissent, and its implications, when speaking truth to power. The last decade shows that the military s robotic acquiescence to political masters is outdated and that there indeed is a place for dissent in today s environment, as long as it remains respectful and private

Very high gravity (VHG) brewing is one of the most promising methods to enhance productivity and reduce costs in brewing industry. Although the principles of this method are well known, stress imposed on yeast due to high solute concentrations and quality problems with the final product have limited the use of VHGB in industrial scale. The goal of this thesis was to compare the performance and viability of a brewing yeast variant adapted to stressful conditions with non-adapted parent strain, to study the flavour profile and other quality attributes of beers produced by VHG method, and to research the technical feasibility of VHG brewing in pilot scale. Attenuation of 77 % in normal gravity (15 °P) all-malt wort was reached in 65 h with the variant, almost 100 h faster than with the parent strain. Maximum attenuation reached by variant was 80.0 ± 0.08 % in 113.8 h and by parent strain 77.7 ± 0.11 % in 193.3 h. Sensory quality of the beer was slightly impaired in the variant beer, mostly due to increased diacetyl content. Very high gravity experiments were done with 25 °P wort’s, containing a 15 °P fraction of all-malt wort and either 10 °P fraction of malt extract or 5 °P fraction of malt extract and 5 °P fraction of barley starch. Complete attenuation was not reached in either of the VHG wort’s due to low yeast viability (18.3 ± 0.3 % in barley starch -containing wort and 35.1 ± 5.3 % in malt extract wort) at the end of fermentations. Attenuation of 78.5 ± 0.04 % and alcohol content of 12.1 ± 0.3 vol-% was anyway reached in less than 100 h with the barley starch -containing wort. Sensory evaluation revealed no significant differences between VHG beers, or between VHG and normal gravity beers, but foam stability was significantly reduced when compared to all-malt beer. Scale-up experiment done with 25 °P barley starch wort in 36 l scale attained 80.5 % attenuation and 11.6 ± 0.01 vol-% alcohol content in 93 h. Final yeast viability was 73.4 %, demonstrating the feas, Oluen valmistus erittäin vahvasta (yli 18 °P) kantavierteestä on yksi lupaavimmista keinoista tuottavuuden lisäämiseen ja kustannusten vähentämiseen panimoteollisuudessa. Vaikka menetelmän periaate onkin tunnettu, on käyttö teollisessa mittakaavassa rajoittanut vierteen korkean hiilihydraattipitoisuuden aiheuttama hiivan elävyyden heikkeneminen sekä lopputuotteiden laatuongelmat. Työn tavoitteena oli tutkia erittäin vahvan kantavierteen käymisen toteutettavuutta ja teknisiä ominaisuuksia, lopputuotteen makuprofiilia ja muita laatuominaisuuksia, sekä verrata osmoja etanolitolerantin panimohiivakannan suorituskykyä ja elävyyttä perinteiseen panimohiivakantaan. Normaalin kantavierrevahvuuden (15 °P) kokeessa saavutettiin 77 % käymisaste 65 tunnissa adaptoidulla hiivalla, lähes 100 tuntia nopeammin kuin adaptoimattomalla kannalla. Suurin saavutettu käymisaste adaptoidulle hiivalle oli 80,0 ± 0,08 % 113,8 tunnissa ja adaptoimattomalle hiivalle 77,7 ± 0,11 % 193,3 tunnissa. Adaptoidulla kannalla tehdyn oluen aistinvarainen laatu oli heikompi kasvaneen diasetyylipitoisuuden seurauksena. Korkean kantavierteen kokeet tehtiin 15 °P täysmallaskantavierteellä, johon oli lisätty joko 10 °P mallasuutetta, tai 5 °P ohratärkkelystä sekä 5 °P mallasuutetta kantavierrepitoisuuden nostamiseksi. Käyminen pysähtyi tässä kokeessa kummallakin vierteellä ennen teoreettisen maksimikäymisasteen saavuttamista. Hiivan elävyys käymisen loppuvaiheessa oli 18,3 ± 0,3 % ohratärkkelysvierteessä ja 35,1 ± 5,3 % mallasuutevierteessä. Ohratärkkelysvierteellä saavutettiin korkeampi käymisaste (78,5 ± 0,04 %) ja alkoholipitoisuus (12,1 ± 0,3 til-%) kuin mallasuutevierteellä. Aistinvarainen arviointi ei paljastanut tilastollisesti merkittäviä eroja oluiden välillä, mutta vaahdon pysyvyys oli heikentynyt huomattavasti täysmallasoluisiin verrattuna. Viimeisessä koesarjassa ohratärkkelysvierrettä käytettiin 36 l mittakaavassa. Käymisasteeksi saatiin tällöin 80,5 % ja alkoholipitoisuudeksi 11,6 ± 0,01 til-%

This and the companion paper that follows owe their existence to a paper presented by Kevin Hindle at the AGSE Regional Entrepreneurship and Innovation Research Exchange in February 2004. In his paper, Hindle (2004) argued passionately that entrepreneurship researchers must ensure that the best of their hardwon wisdom does not find its beginning motivation and final resting place in the pages of arcane journals that practitioners never read. He suggested that if every entrepreneurship researcher committed, say once every two years, to write a "how to" article it would significantly enhance the status of the research community in the eyes of practising entrepreneurs and those who provide support and services to them. The argument was well-received, particularly by two people in the audience, Robert Anderson, the managing editor of the Journal of Small Business and Entrepreneurship, the journal of the Canadian Council for Small Business and Entrepreneurship/Conseil Canadien des PME et de l'entrepreneuriat (CCSBE/ CCPME), and Brian Gibson, the editor of Small Enterprise Research, the journal of the Small Enterprise Association of Australia and New Zealand (SEAANZ). For both editors, Hindle's argument was a familiar one. The membership of CCSBE/CCPME and SEAANZ consists of academic researchers, educators, government employees in both policy and program areas, and those offering support and services to entrepreneurs and the managers of small enterprises. In both organizations, there is a general consensus that the needs of "academics" are well met, but not so the needs of the non-academic constituents.

Recent studies found a disproportionate number of converts to Islam taking part in radical activities as opposed to those born into the faith. While research linking conversion to radicalization is available, a gap exists in research examining what in the conversion process is causing this phenomenon. This thesis asks, what is the relationship between religious conversion and violent extremism? This study explores 38 individuals who converted to Islam and subsequently committed a radical act. The thesis investigates four hypotheses concerning sociological and psychological factors driving religious conversion. These driving factors are a lack of secure attachments, interpersonal connections, significant personal problems, and individuals with perceived grievances being targeted by recruiters. The most significant driving factor in radicalization was individuals who had significant personal problems in their lives leading up to conversion, especially if a previous connection to a radical milieu existed. Recruiters seeking targets of opportunity among aggrieved individuals to convert was not a significant driving factor. Religious conversion by itself should not raise red flags, but conversion with other underlying factors indicates a greater risk for radicalization. The underlying factors are the drivers of radicalization, and the conversion gives individuals a reason to manifest their radical tendencies., http://archive.org/details/inbadfaithlinkbe1094558299, Assistant to the Special Agent in Charge, United States Secret Service, San Francisco Field Office, Approved for public release; distribution is unlimited.

This thesis considers the problems of remote temperature measurement, using a pyro-electric vidicon (PEV) to image small areas of biological tissue heated by laser irradiation. This is applied specifically to laser-assisted vascular anastomosis (LAVA), which is a surgical technique that aims to bond apposed tissue edges. It is a technique which has shown potential but the results have not been consistently successful. In order to understand the bond mechanism and to ascertain the optimum bond temperature, a number of authors have measured the temperature at the bond site using remote thermal imagers. However, if the limitations of the imager are not taken into account, then the temperature will be underestimated. These limitations were investigated extensively for the PEV but the principles apply to all thermal imagers. In particular, a minimum source width of 6 mm was required in order to avoid an underestimation of the temperature and considering the laser spot size was approximately 1.5 mm, large errors could be expected depending on the imager employed. In our case, errors of 20