888 resultados para Conversion to Islam


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Im Immunsystem spielen regulatorische T-Zellen (Treg) eine essentielle Rolle bei der Unterdrückung und Eindämmung von überschüssigen oder schädlichen Immunreaktionen. Ihre suppressiven Eigenschaften wirken aber auch bei Immune Escape Mechanismen von Tumoren mit und können den Erfolg von Tumorimmuntherapien deutlich mindern.rnIn dieser Arbeit konnte zum ersten Mal die Frequenz verschiedener Treg Subpopulationen im peripheren Blut von gesunden Spendern und Melanompatienten in verschiedenen Stadien der Erkrankung verglichen werden. Dabei wurden Treg-Subpopulationen mit den Markerkombinationen CD4+CD25++, CD4+CD25+CD127low, CD4+CD25+HLA DR+, CD4+Foxp3+, CD4+Foxp3+CD25+, CD4+Foxp3+CD127low und CD4+Foxp3+HLA DR+ untersucht. Insbesondere bei den Subpopulationen, die durch die Expression von Foxp3 charakterisiert sind, konnten in Patienten im Spätstadium IV der Melanomerkrankung, verglichen mit Patienten im Stadium I-II oder gesunden Spendern, erhöhte Treg Frequenzen im peripheren Blut festgestellt werden. Diese Funde korrelierten mit der Beobachtung einer verminderten antigenspezifischen T Zellreaktivität in solchen Melanompatienten. Des Weiteren zeigte sich, dass eine DC basierte Tumorantigen-spezifische Immuntherapie bei einem Teil der behandelten Stadium IV Melanompatienten eine Abnahme der Treg Frequenzen im peripheren Blut zur Folge hatte. Dies korrelierte mit Beobachtungen aus vorangegangenen Studien unserer Arbeitsgruppe, bei denen sich zeigte, dass eine solche Immuntherapie die zuvor supprimierten T Zellantworten zumindest vorübergehend wiederherstellen kann. Bei Untersuchungen zur Expression des IL 1-Rezeptors-1 konnte dieser auf Proteinebene als verstärkt exprimierter Aktivierungsmarker auf Treg bestätigt werden. In Anwesenheit von IL-1 wird die Suppressorfunktion der Treg inhibiert. Eine Konversion von humanen Treg zu nicht suppressorischen TH-17-Zellen durch die Kostimulation mit IL 1 konnte dabei nicht nachgewiesen werden. Vielmehr scheint die Induktion von IL 2 die entscheidende Wirkung von IL 1 auf humane Treg und Teff darzustellen.rn

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La tesi affronta la vita e la riflessione politica di Beatrice Potter collocandola all’interno del pensiero politico britannico ed europeo della fine dell’Ottocento e dei primi decenni del Novecento. Rispetto alla maggior parte della bibliografia disponibile, risulta un’autonomia e un’originalità anche rispetto alla riflessione del marito Sidney Webb. La riflessione politica di Potter è caratterizzata in primo luogo dalla ricerca del significato immediatamente politico di quella scienza sociale, che si sta affermando come approccio scientifico dominante nell’intero panorama europeo. Il lavoro è diviso in tre ampi capitoli così suddivisi: il primo ricostruisce l’eredità intellettuale di Potter, con particolare attenzione al rapporto con la filosofia evoluzionista di Herbert Spencer, suo mentore e amico. In questo capitolo vengono anche discussi i contributi di John Stuart Mill, Joseph Chamberlain, Alfred Marshall e Karl Marx e la loro influenza sull’opera di Potter. Il secondo capitolo prende in esame la sua opera prima dell’incontro con il marito e mostra come lo studio della povertà, del lavoro, della metropoli, della cooperazione e delle condizioni delle donne getti le basi di tutta la produzione successiva della partnership. Lo studio politico della povertà, cioè la messa a punto di una scienza amministrativa del carattere sociale del lavoro, rappresenta uno degli elementi principali di quella che viene qui definita un’epistemologia della democrazia. Il terzo capitolo riprende il tema cruciale della democrazia nella sua accezione «industriale» e indaga il ruolo funzionale dello Stato, anche in relazione alla teoria pluralista di Harold Laski, al socialismo guildista di George D. H. Cole e all’idealismo di Bernard Bosanquet. Centrale in questo confronto del pensiero di Potter con il più ampio dibattito degli anni venti e trenta sulla sovranità è la concezione della decadenza della civiltà capitalista e dell’emergere di una new civilisation, dopo la conversione al comunismo sovietico.

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BACKGROUND: To develop risk-adapted prevention of psychosis, an accurate estimation of the individual risk of psychosis at a given time is needed. Inclusion of biological parameters into multilevel prediction models is thought to improve predictive accuracy of models on the basis of clinical variables. To this aim, mismatch negativity (MMN) was investigated in a sample clinically at high risk, comparing individuals with and without subsequent conversion to psychosis. METHODS: At baseline, an auditory oddball paradigm was used in 62 subjects meeting criteria of a late risk at-state who remained antipsychotic-naive throughout the study. Median follow-up period was 32 months (minimum of 24 months in nonconverters, n = 37). Repeated-measures analysis of covariance was employed to analyze the MMN recorded at frontocentral electrodes; additional comparisons with healthy controls (HC, n = 67) and first-episode schizophrenia patients (FES, n = 33) were performed. Predictive value was evaluated by a Cox regression model. RESULTS: Compared with nonconverters, duration MMN in converters (n = 25) showed significantly reduced amplitudes across the six frontocentral electrodes; the same applied in comparison with HC, but not FES, whereas the duration MMN in in nonconverters was comparable to HC and larger than in FES. A prognostic score was calculated based on a Cox regression model and stratified into two risk classes, which showed significantly different survival curves. CONCLUSIONS: Our findings demonstrate the duration MMN is significantly reduced in at-risk subjects converting to first-episode psychosis compared with nonconverters and may contribute not only to the prediction of conversion but also to a more individualized risk estimation and thus risk-adapted prevention.

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The aim of the study was to examine the economic performance as well as perceived social and environmental impacts of organic cotton in Southern Kyrgyzstan on the basis of a comparative field study (44 certified organic farmers and 33 conventional farmers) carried out in 2009. It also investigated farmers’ motivation for and assessment of conversion to organic farming. Cotton yields on organic farms were found to be 10% lower whereby input costs per unit were 42% lower, which resulted in organic farmers having a 20% higher revenue from cotton. Due to lower input costs and organic and fair trade price premiums the average gross margin from organic cotton was 27%. In addition to direct economic benefits organic farmers enjoy a number of additional benefits such as easy access to credits on favourable terms, provision with uncontaminated cotton cooking oil and seed cake as animal feed, marketing support as well as extension and training, services provided by the newly established organic service provider. A big majority of organic farmers perceives an improvement of soil qualities, improved health conditions, and positively assesses their previous decision to convert to organic farming. The major disadvantage of organic farming is the high manual labour input required. In the study area, where manual farm work is mainly women’s work and male labour migration widespread, women are most affected by this negative aspect of organic farming. Altogether, the results suggest that despite the inconvenience of higher work load the advantages of organic farming outweigh the disadvantages and that conversion to organic farming can improve the livelihoods of small-scale farmers.

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Analog filters and direct digital filters are implemented using digital signal processing techniques. Specifically, Butterworth, Elliptic, and Chebyshev filters are implemented using the Motorola 56001 Digital Signal Processor by the integration of three software packages: MATLAB, C++, and Motorola's Application Development System. The integrated environment allows the novice user to design a filter automatically by specifying the filter order and critical frequencies, while permitting more experienced designers to take advantage of MATLAB's advanced design capabilities. This project bridges the gap between the theoretical results produced by MATLAB and the practicalities of implementing digital filters using the Motorola 56001 Digital Signal Processor. While these results are specific to the Motorola 56001 they may be extended to other digital signal processors. MATLAB handles the filter calculations, a C++ routine handles the conversion to assembly code, and the Motorola software compiles and transmits the code to the processor

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Cotton is a leading agricultural non-food commodity associated with soil degradation, water pollution and pesticide poisoning due to high levels of agrochemical inputs. Organic farming is often promoted as a means of addressing the economic, environmental and health risks of conventional cotton production, and it is slowly gaining ground in the global cotton market. Organic and fair trade cotton are widely seen as opportunities for smallholder farmers to improve their livelihoods thanks to higher returns, lower input costs and fewer risks. Despite an increasing number of studies comparing the profitability of organic and non-organic farming systems in developing and industrialized countries, little has been published on organic farming in Central Asia. The aim of this article is to describe the economic performance and perceived social and environmental impacts of organic cotton in southern Kyrgyzstan, drawing on a comparative field study conducted by the author in 2009. In addition to economic and environmental aspects, the study investigated farmers’ motivations toward and assessment of conversion to organic farming. Cotton yields on organic farms were found to be 10% lower, while input costs per unit were 42% lower; as a result, organic farmers’ cotton revenues were 20% higher. Due to lower input costs as well as organic and fair trade price premiums, the average gross margin from organic cotton was 27% higher. In addition to direct economic benefits, organic farmers enjoy other benefits, such as easy access to credit on favorable terms, provision of uncontaminated cottonseed cooking oil and cottonseed cake as animal feed, and marketing support as well as extension and training services provided by newly established organic service providers. The majority of organic farmers perceive improved soil quality, improved health conditions, and positively assess their initial decision to convert to organic farming. The major disadvantage of organic farming is the high manual labor input required. In the study area, where manual farm work is mainly women's work and male labor migration is widespread, women are most affected by this negative aspect of organic farming. Altogether, the results suggest that, despite the inconvenience of a higher workload, the advantages of organic farming outweigh its disadvantages and that conversion to organic farming improves the livelihoods of small-scale farmers.

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The early detection and treatment of people at risk for psychosis is currently regarded as a promising strategy in fighting the devastating consequences of psychotic disorders. Currently, the 2 most broadly used sets of at-risk criteria, that is, ultra-high risk (UHR) and basic symptom criteria, were developed mainly in adult samples. We review the data regarding the presence and relevance of at-risk symptoms for psychosis in children and adolescents. The few existing studies suggest that attenuated psychotic symptoms (APS) and brief limited intermittent psychotic symptoms (BLIPS) do have some clinical relevance in young adolescents from the general population. Nevertheless, their differentiation from atypical psychotic symptoms or an emerging schizotypal personality disorder, as well as their stability and predictive accuracy for psychosis, are still unclear. Further, standard interviews for UHR criteria do not define a minimum age for the assessment of APS and BLIPS or guidelines as to when and how to include information from parents. APS and basic symptoms may be predictive of conversion to psychosis in help-seeking young adolescents. Nevertheless, the rate and timing, and thus the required observation time, need further study. Moreover, no study has yet addressed the issue of how to treat children and adolescents presenting with at-risk symptoms and criteria. Further research is urgently needed to examine if current at-risk criteria and approaches have to be tailored to the special needs of children and adolescents. A preliminary rationale for how to deal with at-risk symptoms for psychosis in clinical practice is provided.

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In this 12-month multicenter Scandinavian study, 78 maintenance heart transplant (HTx) recipients randomized to everolimus with reduced calcineurin inhibitor (CNI) exposure or continued standard CNI-therapy underwent matched virtual histology (VH) examination to evaluate morphological progression of cardiac allograft vasculopathy (CAV). Parallel measurement of a range of inflammatory markers was also performed. A similar rate of quantitative CAV progression was observed in the everolimus (n = 30) and standard CNI group (n = 48) (plaque index 1.9 ± 3.8% and 1.6 ± 3.9%, respectively; p = 0.65). However, VH analysis revealed a significant increase in calcified (2.4 ± 4.0 vs. 0.3 ± 3.1%; p = 0.02) and necrotic component (6.5 ± 8.5 vs. 1.1 ± 8.6%; p = 0.01) among everolimus patients compared to controls. The increase in necrotic and calcified components was most prominent in everolimus patients with time since HTx >5.1 years and was accompanied by a significant increase in levels of von Willebrand (vWF) factor (p = 0.04) and vascular cell adhesion molecule (VCAM) (p = 0.03). Conversion to everolimus and reduced CNI is associated with a significant increase in calcified and necrotic intimal components and is more prominent in patients with a longer time since HTx. A significant increase in vWF and VCAM accompanied these qualitative changes and the prognostic implication of these findings requires further investigation.

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Maternal effects are a mother¿s non-genetic contributions to development that alter phenotypic traits in offspring. Maternal effects can take the form of prenatal allocation of resources, such as the deposition of androgens into egg yolks. For example, elevated yolk testosterone increases male sexual behaviors such as copulation solicitation and courtship displays in some avian species, in addition to aggressive behaviors like pecks and intimidating postures towards same-sex competitors. However, the mechanism connecting in ovo testosterone exposure with changes in sexual and aggressive behaviors has yet to be elucidated. While testosterone released by the gonads is important in the activation of sexual behaviors, it must undergo conversion to estrogen by the enzyme aromatase in the pre-optic area (POA) of the avian brain for full expression of sexual activity. POA aromatase is also necessary for the activation of aggressive behaviors in male birds. This experiment tested the hypothesis that elevated yolk testosterone leads to changes in POA aromatase activity and levels of gonadal testosterone, as these two endocrine parameters may mediate the effect of yolk testosterone on the frequency of sexual and aggressive behaviors. The effect of elevated yolk testosterone on gonadal testosterone levels and aromatase activity in the POA of 3-day-old domestic chickens Gallus gallus domesticus was investigated. Unincubated eggs were injected with either 10 ng testosterone in 50 ¿L sesame oil (¿T chicks¿) or 50 ¿L sesame oil (¿C chicks¿). At 3 days post-hatch, gonadal testosterone content was measured after steroid extraction using an EIA, and aromatase activity in the POA was quantified by measuring the production of tritiated water from [1ß-3H]-androstenedione. I predicted that gonadal testosterone levels and brain aromatase activity would be higher in T chicks, however found no difference between treatments. Though juvenile T production peaks at 3 days post-hatch, it is possible that the reproductive systems, including the testes and POA, are not fully developed at this time.

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ABSTRACT FOR PART I: PHOSPHA-MICHAEL ADDITIONS TO ACTIVATED INTERNAL ALKENES: STERIC AND ELECTRONIC EFFECTS A method for the phospha-Michael addition of bis(4-methyl)phenyl phosphine oxide to activated internal alkenes has been developed. Michael acceptors including cinnamates, crotonates, chalcones, and internal alkenes containing multiple activating groups were all successfully utilized in this reaction. The reaction was fairly tolerant of electron-donating and electron-withdrawing substituents on the Michael acceptor, and moderate to excellent yields (49-96%) of the adducts were isolated. When steric bulk was increased by a second substituent on the -position of the Michael-acceptor the reaction was suppressed. This was usually overcome by adding a second activating substituent to the -position. ABSTRACT FOR PART II: MICROWAVE-ASSISTED ARYLGOLD BOND FORMATION A microwave-assisted method was developed for the formation of arylgold complexes containing (2-Biphenyl)di-tert-butylphosphine (JohnPhos) as the supporting phosphine ligand. Arylboronic acids with increasingly bulky aromatic groups were screened to determine the steric limitations of the reaction. Arylgold complexes (JohnPhos)Au(p-methoxyphenyl), (JohnPhos)Au(2,4,6-trimethylphenyl), and (JohnPhos)Au(4-bromo-10-anthracene) were all synthesized by microwave irradiation at 70ºC in the presence of Cs2CO3 in either THF or iPrOH. Reactions performed with arylboronic acids containing unhindered ortho positions were carried out in THF. Arylboronic acids with substituents on the ortho position required iPrOH as the reaction solvent. Arylboronic acids with extreme steric hindrance on the ortho position of the aryl substituent, 2,4,6-triisopropylpphenylboronic acid, were unreactive. It was determined that increasing the irradiation temperature increased the formation of side products, therefore to promote conversion to the arylgold complex the duration of the reaction time was increased while maintaining a temperature of 70ºC. Arylgold complexes (JohnPhos)Au(p-methoxyphenyl), (JohnPhos)Au(2,4,6-trimethylphenyl), and (JohnPhos)Au(4-bromo-10-anthracene) were synthesized with moderate yields (40-69%).

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A numerous studies suggest that Vitamin E has a preventive role in atherosclerosis, although the mechanism of action still remains unclear. CD36, a member of the scavenger receptor family is centrally involved in the uptake of oxidized low density proteins (oxLDLs) from bloodstream. During the atherosclerotic process, the lipid cargo of oxLDL accumulates in macrophages and smooth muscle cells, inducing their pathological conversion to foam cells. In the present study, we investigate the role of Vitamin E on CD36 expression in an in vivo model. Atherosclerosis was induced by a 2% cholesterol containing Vitamin E poor diet. Three groups of six rabbits each were studied. The first group (control) was fed on Vitamin E poor diet. The second group was fed with Vitamin E poor diet containing 2% cholesterol and the rabbits in the third group were fed with Vitamin E poor diet containing 2% cholesterol and received injections of 50 mg/kg of Vitamin E i.m. After 4 weeks, aortas were removed and analysed by light microscopy for atherosclerotic lesions. Aortic samples were analysed for CD36 mRNA expression. The aortas of cholesterol-fed rabbits showed typical atherosclerotic lesions, detected by macroscopic and microscopic examination, and exhibited an increase in CD36 mRNA expression. Vitamin E fully prevented cholesterol induced atherosclerotic lesions and the induction of CD36 mRNA expression. The effects observed at the level of CD36 scavenger receptor expression in vivo suggest an involvement of reduced foam cell formation in the protective effect of Vitamin E against atherosclerosis.

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OBJECTIVES: In patients with a clinically isolated syndrome (CIS), the time interval to convert to clinically definite multiple sclerosis (CDMS) is highly variable. Individual and geographical prognostic factors remain to be determined. Whether anti-myelin antibodies may predict the risk of conversion to CDMS in Swiss CIS patients of the canton Berne was the subject of the study. METHODS: Anti-myelin oligodendrocyte glycoprotein and anti-myelin basic protein antibodies were determined prospectively in patients admitted to our department. RESULTS: After a mean follow-up of 12 months, none of nine antibody-negative, but 22 of 30 antibody-positive patients had progressed to CDMS. Beta-Interferon treatment delayed the time to conversion from a mean of 7.4 to 10.9 months. CONCLUSIONS: In a Swiss cohort, antibody-negative CIS patients have a favorable short-term prognosis, and antibody-positive patients benefit from early treatment.

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PURPOSE: To elucidate the association of impaired pulmonary status (IPS) and diabetes mellitus (DM) with clinical outcome and the incidences of aortic neck dilatation and type I endoleak after elective endovascular infrarenal aortic aneurysm repair (EVAR). METHODS: In 164 European institutions participating in the EUROSTAR registry, 6383 patients (5985 men; mean age 72.4+/-7.6 years) underwent EVAR. Patients were divided into patients without versus with IPS or with/without DM. Clinical assessment and contrast-enhanced computed tomography (CT) were performed at 1, 3, 6, 12, 18, and 24 months and annually thereafter. Cumulative endpoint analysis comprised death, aortic rupture, type I endoleak, endovascular reintervention, and surgical conversion. RESULTS: Prevalence of IPS was 2733/6383 (43%) and prevalence of DM was 810/6383 (13%). Mean follow-up was 21.1+/-18.4 months. Thirty-day mortality, AAA rupture, and conversion rates did not differ between patients with versus without IPS and between patients with versus without DM. All-cause and AAA-related mortality, respectively, were significantly higher in patients with IPS compared to patients with normal pulmonary status (31.0% versus 19.0%, p<0.0001 and 6.8% versus 3.3%, p = 0.0057) throughout follow-up. In multivariate analysis adjusted for smoking, age, gender, comorbidities, fitness for open repair, co-existing common iliac aneurysm, neck and aneurysm size, arterial angulations, aneurysm classification, endograft oversizing >or=15%, and type of stent-graft, the presence of IPS was not associated with significantly higher rates of aortic neck dilatation (30.6% versus 38.0%, p>0.05) and did not influence cumulative rates of type I endoleak, endovascular reintervention, or conversion to open surgery (p>0.05). Similarly, the presence of DM did not influence the above-mentioned study endpoints. CONCLUSION: In contrast to observations regarding the natural course of AAAs, impaired pulmonary status does not negatively influence aortic neck dilatation, while the presence of diabetes does not protect from these dismal events after EVAR.

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The production by biosynthesis of optically active amino acids and amines satisfies the pharmaceutical industry in its demand for chiral building blocks for the synthesis of various pharmaceuticals. Among several enzymatic methods that allow the synthesis of optically active aminoacids and amines, the use of minotransferase is a promising one due to its broad substrate specificity and no requirement for external cofactor regeneration. The synthesis of chiral compounds by aminotransferases can be done either by asymmetric synthesis starting from keto acids or ketones, and by kinetic resolution starting from racemic aminoacids or amines. The asymmetric synthesis of substituted (S)-aminotetralin, an active pharmaceutical ingredient (API), has shown to have two major factors that contribute to increasing the cost of production. These factors are the raw material cost of biocatalyst used to produce it and product loss during biocatalyst separation. To minimize the cost contribution of biocatalyst and to minimize the loss of product, two routes have been chosen in this research: 1. To engineer the aminotransferase biocatalyst to have greater specific activity, and 2. Improve the engineering of the process by immobilization of biocatalyst in calcium alginate and addition of cosolvents. An (S)-aminotransferase (Mutant CNB03-03) was immobilized, not as purified enzyme but as enzyme within spray dried cells, in calcium alginate beads and used to produce substituted (S)-aminotetralin at 50 °C and pH 7 in experiments where the immobilized biocatalyst was recycled. Initial rate of reaction for cycle 1 (6 hr duration) was determined to be 0.258 mM/min, for cycle 2 (20 hr duration) it decreased by ~50% compared to cycle 1, and for cycle 3 (20 hr duration) it decreased by ~90% compared to cycle 1 (immobilized preparation consisted of 50 mg of spray dried cells per gram of calcium alginate). Conversion to product for each cycle decreased as well, from 100% in cycle 1 (About 50 mM), 80% in cycle 2, and 30% after cycle 3. This mutant was determined to be deactivated at elevated temperatures during the reaction cycle and was not stable enough to allow multiple cycles in its immobilized form. A new mutant aminotransferase was isolated by applying error-prone polymerase chain reaction (PCR) on the gene coding for this enzyme and screening/selection: CNB04-01. This mutant showed a significant improvement in thermostability in comparison to CNB03-03. The new mutant was immobilized and tested under similar reaction conditions. Initial rate remained fairly constant (0.2 mM/min) over four cycles (each cycle with a duration of about 20 hours) with the mutant retaining almost 80% of initial rate in the fourth cycle. The final product concentrations after each cycle did not decrease during recycle experiments. Thermostability of CNB04-01 was much improved compared to CNB03-03. Under the same reaction conditions as stated above, the addition of co-solvents was studied in order to increase substituted tetralone solubility. Toluene and sodium dodecylsulfate (SDS) were used. SDS at 0.01% (w/v) allowed four recycles of the immobilized spray dried cells of CNB04-01, always reaching higher product concentration (80-85 mM) than the system with toluene at 3% (v/v) -70 mM-. The long term activity of immobilized CNB04-01 in a system with SDS 0.01% (w/v) at 50 °C, pH 7 was retained for three cycles (20 to 24 hours each one), reaching always final product concentration between 80-85 mM, but dropping precipitously in the fourth cycle to a final product concentration of 50 mM. Although significant improvement of immobilization on productivity and stability were observed using CNB04-01, another observation demonstrated the limitations of an immobilization strategy on reducing process costs. After analyzing the results of this experiment it was seen that a sudden drop occurred on final product concentration after the third recycle. This was due to product accumulation inside the immobilized preparation. In order to improve the economics of the process, research was focused on developing a free enzyme with an even higher activity, thus reducing raw material cost as well as improving biomass separation. A new enzyme was obtained (CNB05-01) using error-prone PCR and screening using as a template the gene derived from the previous improved enzyme. This mutant was determined to have 1.6 times the initial rate of CNB04-01 and had a higher temperature optimum (55°). This new enzyme would allow reducing enzyme loading in the reaction by five-fold compared to CNB03-03, when using it at concentration of one gram of spray dried cells per liter (completing the reaction after 20-24 hours). Also this mutant would allow reducing process time to 7-8 hours when used at a concentration of 5 grams of spray dried cells per liter compared to 24 hours for CNB03-03, assuming that the observations shown before are scalable. It could be possible to improve the economics of the process by either reducing enzyme concentration or reducing process time, since the production cost of the desired product is primarily a function of both enzyme concentration and process time.

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Universities in the United States are applying more sustainable approaches to their dining service operations. "The increase in social consciousness and environmental stewardship on college campuses has spurred an array of new and innovative sustainability programs"(ARAMARK Higher Education 2008). University residence dining is typically cafeteria style, with students using trays to carry food. Studies report that food served without trays substantially reduces food waste and water and electrical consumption associated with washing trays. Commonly, these reported results are estimates and not measurements taken under actual operating conditions. This study utilizes measurements recorded under actual dining service conditions in student residence halls at Michigan Technological University to develop the following: 1) operational-specific data on the issues and potential savings associated with a conversion to trayless dining and 2) life cycle assessment (LCA) cost and environmental impact analyses comparing dining with and without trays. For the LCA, the entire life cycle of the system is considered, from the manufacturing to the usage and disposal phases. The study shows that trayless dining reduces food waste because diners carry less food. The total savings for the diner shifts when not using trays for the standard academic year (205 days), with an average number of 700 diners, is 7,032 pounds of food waste from the pre-rinse area (33% reduction) and 3,157 pounds of food waste from the pan washing area (39% reduction). In addition, for each day of the study, the diners consumed more food during the trayless portion of the experiment. One possible explanation for the increased food consumption during this short duration study could be that the diners found it more convenient to eat the extra food on their plate rather than carrying it back for disposal. The trayless dining experiment shows a reduction in dishwasher water, steam, and electrical consumption for each day of the study. The average reduction of dishwasher water, steam, and electrical consumption over the duration of the study were 10.7%, 9.5%, and 6.4% respectively. Trayless dining implementation would result in a decrease of 4,305 gallons of consumption and wastewater discharge, 2.87 mm BTU of steam consumption, and 158 kWh of electrical consumption for the dinner shift over the academic year. Results of the LCA indicate a total savings of $190.4 when trays are not used during the dinner shift. Trayless dining requires zero CO2 eq and cumulative energy demand in the manufacturing stage, reductions of 1005 kg CO2 eq and 861 MJ eq in the usage phase, and reductions of 6458 kg CO2 eq and 1821 MJ eq in the end of the life cycle.