Dissertations / Theses on the topic 'Products of technical microbiology'

The production of biotherapeutics including antibodies and antibody fragments is a rapidly expanding market with an increasing number of products being approved for use. One of the major platforms used for production of such therapeutics is Escherichia coli, which offers a rapid production at low production costs. The favoured location for targeting these biotherapeutic is the periplasm of E. coli as this environment supports the formation of disulphide bonds and simplifies the purification process. There are a number of periplasmic release procedures currently practised in industry including osmotic shock. However their limitations call for the development of an improved generic periplasmic release method. This project demonstrates how the polymer poly(styrene-co-maleic acid) (SMA) can be applied as a novel and alternative periplasmic release agent. The amphipathic polymer self-assembles into discs encapsulating membrane proteins and thereby destabilises the outer membrane consequently releasing the periplasm. Data presented here show that SMA releases the model target proteins with a higher yield at equal or higher target purity than the conventional methods. Furthermore the developed methods was analysed and refined to be compatible with existing downstream and first steps for its adaptation on industrial scale were made.

<p> <i>Mycobacterium tuberculosis</i> (<i>Mtb</i>) is a bacterium causing great morbidity and mortality especially in developing countries. In order to identify possible areas of intervention to positively alter the history of the disease, a better identification and characterization of <i>Mtb</i> virulence determinants is required. Specifically, biosynthetic routes for these virulence determinants should be pursued. Furthermore, the interaction between the host and <i>Mtb</i> virulence determinants should be characterized at a molecular level. It is hoped that unraveling these pathogenesis mechanisms could lead to novel strategies to combat the infection. </p><p> In Chapter II, the identification of secreted <i>Mtb</i> molecules that induce macrophage apoptosis was performed. Apoptosis is a mechanism of host cell death and in the life cycle of <i>Mtb</i>, different modalities of host cell death have been suggested to tip the balance between bacterial eradication and multiplication. However, a systematic approach to identify and characterize secreted <i>Mtb</i> molecules that modulate host cell death, has not been performed. Surprisingly, extracellular <i>Mtb </i> RNA fragments were identified as a potent inducer of host cell apoptosis. This extracellular RNA was identified as predominantly rRNA and tRNA fragments that accumulated early during <i>in vitro</i> culture of <i>Mtb</i>. Mechanistic studies determined that the <i> Mtb</i> RNA induced macrophage apoptosis through a caspase-8-dependent, TNF-&alpha;-independent mechanism. Importantly, <i>Mtb</i> RNA abrogated the macrophage's ability to control an <i>Mtb</i> infection. In Chapter II, the first description of an extracellular <i>Mtb</i> RNA with potent biological activity was performed. This opens an exciting field in research of host interactions with pathogen nucleic acids. </p><p> Chapters III and IV were devoted to identifying the biochemical pathway involved in &alpha;-L-polyGlutamine (&alpha;-L-polyGln) biosynthesis and determining its role in pathogenesis in the murine model of TB. &alpha;-L-polyGln is an <i> Mtb</i>and <i>Mycobacterium bovis</i> (<i>M. bovis</i>) specific product and its presence in virulent <i>Mycobacterium</i> spp., suggest that it could play an important role in pathogenesis. <i> Bacillus anthracis</i> (<i>B. anthracis</i>) synthesizes &gamma;-D-polyGlutamate (&gamma;-D-polyGlu), an amino acid polymer that is present in its capsule and is absolutely required for pathogenicity. As the pathway for <i> B. anthracis</i> &gamma;-D-polyGlu biosynthesis has been well characterized, it was used as a model to start elucidating the <i>Mtb</i> &alpha;-L-polyGln biosynthetic pathway. Bioinformatics analysis suggested that Rv0574c and Rv2394 are the <i>Mtb</i> homologues for B. anthracis CapA and CapD, respectively. In Chapter III, a complete biochemical characterization of Rv2394 was performed. Similar to other &gamma;-glutamyltranspeptidases (GGTs), Rv2394 had a conserved catalytic motif consisting of a Threonine (Thr) residue. Mutating this Thr residue to Alanine (Ala) abrogated the enzymatic activity of Rv2394, including its autocatalytic activation. In contrast to eukaryote GGT, Rv2394 was able to perform a GGT activity in the presence of physiological relevant acceptors such as di- or oligopeptides containing Glutamate (Glu) or Glutamine (Gln). In addition to its autocatalytic activation, Rv2394 was shown to be post-translationally modified with hexose residues. A putative phosphorylation and acylation modification also seemed to be present in Rv2394. </p><p> In Chapter IV, <i>Mtb</i> mutants for <i>rv0574c</i> and <i>rv2394</i> were engineered and characterized biochemically to determine if the concentration of &alpha;-L-polyGln had been altered. Furthermore, the mutant's virulence was evaluated in the murine model of TB. Consistent with a putative role in &alpha;-L-polyGln, both mutants had reduced concentrations of Glu and ammonia in the cell wall. Furthermore, preliminary analysis suggested that the apolar lipid profiles were also altered by these mutations. In the murine model, <i>Mtb</i> mutants had a tendency to grow faster in the initial stages of disease. However, the difference between wild type (WT) and mutant strains was not statistically significant and normalized during the later stages of disease. Furthermore, mutant <i>Mtb</i> also seemed to induce more lung damage. In contrast to bacterial burden, this difference persisted throughout the course of the study. Altogether, these results suggest that Rv0574c and Rv2394 participate in the biosynthesis of &alpha;-L-polyGln. Remarkably, similar biochemical and phenotypic results were obtained for both mutants despite being encoded in different loci. These initial results provide the foundation for future studies characterizing the biochemical pathway involved in &alpha;-L-polyGln biosynthesis.</p>

An atp gene cluster from the extreme acidophile Thiobacillus ferrooxidans ATCC 33020 was cloned by complementation of Escherichia coli unc mutants. Eight different E. coli unc mutants were screened with T. ferrooxidans ATCC 33020 pEcoR251 plasmid and pHC79 cosmid gene banks. The ability of the transformants/transductants to grow on succinate as the sole non-fermentable carbon source was used to select mutants with a functional F₁F₀ ATPsynthase. Many F₁ -complementing plasmids and cosmids were isolated from the four E. coli F₁ unc point mutants screened. No plasmids or cosmids which complemented an E. coli fΔunc strain or any of the three E. coli F₀ mutants screened, were isolated.

This investigation was done with the objective to determine the microbiological load of the main meat products such as: beef, chicken meat, sausage, and viena sausage which are sold in the Riobamba city markets. This investigation was carried out in the Microbiological Laboratory Livestock Science faculty of the Polytechnical Superior school. Specific chemical products were used to determine mesofilas (37 degrees C), xicrofilas (5 degrees C), and termofilas bacteria which did not develop at 45 degrees C, however exicrofilas and mesofilas bacteria were found in every market and meat product in this study. The meat product hygiene is the same in all market conditions. There is no change in the handle or conservation of these products, especially with the handmade products such as sausage and long sausage. My personal point of view is that they are more dangerous for our health because they are not cooked before eaten and because of the way they are conserved. On the contrary, when the meat was cooked, termofilas were not found, since at 50°C temperature, the bacteria begins to be destroyed by the warmth, which give us some confidence to eat cooked food. However, the problem continues because the toxins that the bacteria release are more dangerous, therefore, we must investigate the toxin matter released by the bacteria in the meat products. When meat is eaten, such as hamburgers or roasted meat, there is a risk of acquiring some diseases. The expenses of an investigation of this kind are too high to perform a complete biochemical test which would provide better results that can be relied on. This thesis is patterned to make a project aimed at improvement of the hygiene and quality of these products that are used on a daily basis. In all, the situation in Ecuador is the same as in this city, it is extremely urgent to stress the importance of this issue. The consumption of meat of bad quality is not a good source of nutrition for our people.

Streptomyces bacteria are prolific producers of secondary metabolites. These natural products find uses ranging from antibiotics and antifungals to immunomodulatory agents and pesticides. Biosynthesis of secondary metabolites is often tightly controlled; therefore novel strategies for activation of cryptic secondary metabolites are required. The metabolites of the Streptomyces venezuelae wild type and a mutant strain lacking the ArpA-like transcriptional repressor GbnR have been compared, leading to the identification of the gaburedins – novel, ureido-linked dipeptides – in the gbnR mutant. A combination of in vivo precursor-directed studies has led to a proposed biosynthetic route to gaburedins. Metabolic profiling of a range of other mutant strains has identified gbnB as an essential gene in the gbnABC gene cluster that is responsible for gaburedin biosynthesis. Synthesis of an authentic standard of gaburedin A combined with chiral HPLC analysis of culture extracts has allowed the proposed structure of gaburedins to be confirmed. Bioinformatic analyses of the gbnABC cluster responsible for gaburedin biosynthesis have revealed orthologous systems in a range of other bacterial genera and efforts to reconstitute the S. venezuelae gbnABC pathway in E. coli have begun. The regulatory mechanism controlling gaburedin biosynthesis in S. venezuelae has also been investigated, leading to the discovery of new AHFCA signalling molecules which have been shown to induce gaburedin biosynthesis in a mutant strain unable to produce AHFCAs. This work demonstrates for the first time that AHFCA signalling is involved in regulation of other natural products as well as the methylenomycin cluster from which AHFCAs were first identified. Gaburedins represent the first example by which deletion of an arpA-like regulatory gene has been used as a strategy for de-repression of a biosynthetic pathway for cryptic natural product biosynthesis. The current project demonstrates that rational deletion of proposed regulatory genes is a powerful approach to natural product discovery.

Listeria monocytogenes is a Gram-positive, facultative, intracellular bacterium that can cause severe food-borne illness referred to as listeriosis in both humans and animals. This study has developed a rabbit model for the identification of L. monocytogenes gene products specifically induced during infection by constructing a L. monocytogenes protein expression library followed by differential immunoscreening with two kinds of antisera, one (RaL) from rabbits infected with viable bacteria, and the other (RaK) from animals immunized with heatkilled bacteria. This strategy led to the discovery of several L. monocytogenes proteins, including three members (InlA, InlD, and InlC2) of the internalin family, in which InlA and InlB are known bacterial virulence factors, and five novel proteins of unknown function (designated IspWei, IspLing, IspYu, IspMin, and IspLin, respectively). Library screening and Western blots showed that these proteins reacted only with RaL, indicating that they are specifically induced during infection. (Abstract shortened by UMI.)

The research work presented in this thesis involved an examination of the structure and function of the protein products of the measles virus (MV) P cistron. At least three protein products of the P cistron have been identified in MV infected cells. The largest of these is the P protein, which is translated in a canonical manner from genome faithful transcripts. The V protein is translated from a secondary population of edited mRNAs, and the C protein is generated via alternative translational initiation from both P- and V-specific mRNAs. Previous work in our laboratory had identified and characterized the cellular distribution of the MV C and V proteins in infected cells, but any insight into the function of these proteins was lacking. Contradictory results have been published as to the sub-cellular localization of the paramyxovirus C and V proteins, as well as their presence or absence in the virion.<br>We initiated this work with an examination of the zinc binding capacity of the V protein predicted from the primary sequence of the protein. In order to proceed with the zinc binding experiment, we overexpressed the MV P and V proteins in E. coli using the pGEX expression system. We used the glutathione-S-transferase (GST) fusion protein to demonstrate the specificity of the zinc binding activity in competition assays, as well as localizing the zinc binding domain to the carboxy-terminus of the protein.<br>We then used these and other GST fusion proteins to investigate the in vitro interactions of the MV P, V, and C proteins with other virally encoded proteins, as well as with cellular proteins. We identified three protein-protein interactions; P-L, P-NP, and P-P. The interaction domain of the P protein that binds the L protein, the NP protein, and the P protein was mapped to the carboxy-terminal half of the molecule that lies 3$ sp prime$ to the editing site. The MV C and V proteins were found to interact with specific cellular proteins, but not with any of the virus-specific proteins. These interactions were confirmed in vivo using the yeast two-hybrid system.<br>In order to complete our examination of the protein interactions involved in the viral replication machinery, we proceeded to examine the interactions of the NP protein, again using both GST fusion protein analysis and the yeast two-hybrid system. An array of amino- and carboxy-terminal deletion mutants of the NP protein were expressed as GST fusions and used to map the NP interaction domains with the P protein and with itself.<br>During the course of our investigation of the P and V proteins, we unexpectedly discovered the existence of ribosomal frameshifting on the MV P mRNA. Deletion mutants were constructed in order to localize the frameshift site. The protein product of the construct with the largest deletion that still exhibited the frameshift phenotype was then purified and subjected to protein sequencing. The frameshift site was identified 5 codons upstream of the UAA stop codon that terminates the V reading frame. In addition, two-dimensional gel electrophoresis of anti-V immunoprecipitated viral protein provided strong circumstantial evidence for the existence of the novel protein product, which we have termed R, in infected cells.

Infections of insect cells by baculoviruses are characterized by distinct early and late temporal phases with a transition demarcated by the beginning of viral DNA replication. Three processes characteristic of baculovirus infection occur during the late phase: (1) the production of two phenotypically distinct types of virions, (2) the occlusion of one of these virion types in large proteinaceous structures, and (3) the appearance of a novel DNA-directed RNA polymerase activity that is responsible for baculovirus late gene expression. Many of the polypeptide components of the late phase processes remain to be elucidated. The identification and characterization of two baculovirus late proteins are described in this thesis. The first, gp37 or SLP, is a glycoprotein that represents the major component of spindle-shaped crystal structures which are often observed at the nuclear membrane of infected cells. Purified spindle bodies are associated with an alkaline protease activity. The second late protein, p78/83, is a phosphoprotein associated with an end-structure of the nucleocapsids. It forms complexes with other infected-cell proteins and copurifies with the virus-induced RNA polymerase activity through a number of chromatographic steps.

Actinobacteria, primarily the genus Streptomyces, have led to the development of a number of antibiotics, which result from their secondary metabolites or modified derivatives. Secondary metabolite production can result from competition with neighboring microbes in an effort to disrupt growth, aiding in the competition for vital nutrients in impoverished conditions. Such secondary metabolites have the potential to affect a plethora of cellular functions in target cells, including, cell wall development, protein synthesis, protein function and fatty acid synthesis/metabolism. Due to the pandemic spread of antibiotic resistant bacteria, it is imperative to continue the search for new therapeutic agents targeting these deadly organisms. As such, our group explored soil and marine samples from Tampa Bay’s surrounding farmlands and waterways for secondary metabolite producing microbes using culture methods specific to Actinobacteria. Through these efforts we isolated over 750 bacterial species, of which almost half are confirmed Actinobacteria. In an attempt to derive new and novel chemistry from these organisms, we used our novel collection, and developed techniques for epigenetic modification to un-silence dormant and cryptic metabolic pathways. Our work reveals that a number of these Actinobacteria produce secondary metabolites that are effective against the ESKAPE pathogens, some at very low concentrations. Although the bioactivity from secondary metabolites is a well-known source for antibiotic drug discovery, our epigenetic methods suggest a potential to isolate previously overlooked compounds that have a very real possibility for use as antibacterial therapeutics.

Thesis (MSc)--Stellenbosch University, 2011.<br>ENGLISH ABSTRACT: The need to mitigate the twin crises of peak oil and climate change has driven a headlong rush to biofuels. This study was aimed at the development of a process to efficiently convert steam explosion pretreated (STEX) sugarcane bagasse into ethanol by using combinations of commercial enzyme cocktails and recombinant Saccharomyces cerevisiae strains. Though enzymatic saccharification is promising in obtaining sugars from lignocellulosics, the low enzymatic accessibility of the cellulose and hemicellulose is a key impediment thus necessitating development of an effective pretreatment scheme and optimized enzyme mixtures with essential accessory activities. In this context, the effect of uncatalysed and SO2 catalysed STEX pretreatment of sugarcane bagasse on the composition of pretreated material, digestibility of the water insoluble solids (WIS) fraction and overall sugar recovery was investigated. STEX pretreatment with water impregnation was found to result in a higher glucose recovery (28.1 g/ 100 bagasse) and produced WIS with a higher enzymatic digestibility, thus was used in the optimization of saccharification and fermentation. Response surface methodology (RSM) based on the 33 factorial design was used to optimize the composition of the saccharolytic enzyme mixture so as to maximize glucose and xylose production from steam exploded bagasse. It was established that a combination of 20 FPU cellulase/ g WIS and 30 IU -glucosidases/ g WIS produced the highest desirability for glucose yield. Subsequently the optimal enzyme mixture was used to supplement enzyme activities of recombinant yeast strains co-expressing several cellulases and xylanases in simultaneous saccharification and fermentations SSFs. In the SSFs, ethanol yield was found to be inversely proportional to substrate concentration with the lowest ethanol yield of 70% being achieved in the SSF at a WIS concentration of 10% (w/v). The ultimate process would however be a one-step “consolidated” bio-processing (CBP) of lignocellulose to ethanol, where hydrolysis and fermentation of polysaccharides would be mediated by a single microorganism or microbial consortium without added saccharolytic enzymes. The cellulolytic yeast strains were able to autonomously multiply on sugarcane bagasse and concomitantly produce ethanol, though at very low titres (0.4 g/L). This study therefore confirms that saccharolytic enzymes exhibit synergism and that bagasse is a potential substrate for bioethanol production. Furthermore the concept of CBP was proven to be feasible.<br>AFRIKAANSE OPSOMMING: Die behoefte om die twee krisisse van piek-olie en klimaatsverandering te versag, het veroorsaak dat mense na biobrandstof as alternatiewe energiebron begin kyk het. Hierdie studie is gemik op die ontwikkeling van 'n proses om stoomontplofde voorafbehandelde (STEX) suikerriet bagasse doeltreffend te omskep in etanol deur die gebruik van kombinasies van kommersiële ensiem mengsels en rekombinante Saccharomyces cerevisiae stamme. Alhoewel ensiematiese versuikering belowend is vir die verkryging van suikers vanaf lignosellulose, skep die lae ensiematiese toeganklikheid van die sellulose en hemisellulose 'n hindernis en dus is die ontwikkeling van' n effektiewe behandelingskema en optimiseerde ensiemmengsels met essensiële bykomstige aktiwiteite noodsaaklik. In hierdie konteks, was die effek van ongekataliseerde en SO2 gekataliseerde stoomontploffing voorafbehandeling van suikerriet bagasse op die samestelling van voorafbehandelde materiaal, die verteerbaarheid van die (WIS) breuk van onoplosbare vastestowwe in water (WIS), en die algehele suikerherstel ondersoek. Daar was bevind dat stoomontploffing behandeling (STEX) met water versadiging lei tot 'n hoër suikerherstel (21.8 g/ 100g bagasse) en dit het WIS met ‘n hoër ensimatiese verteerbaarheid vervaardig en was dus gebruik in die optimalisering van versuikering en fermentasie. Reaksie oppervlak metodologie (RSM), gebasseer op die 33 faktoriële ontwerp, was gebruik om die samestelling van die ‘saccharolytic’ ensiemmengsel te optimaliseer om sodoende die maksimering van glukose en ‘xylose’ produksie van stoomontplofde bagasse te optimaliseer. Daar was bevestig dat ‘n kombinasie van 20 FPU sellulase/ g WIS en 30 IU ‘ -glucosidases/ g’ WIS die hoogste wenslikheid vir glukose-opbrengs produseer het. Daarna was die optimale ensiemmengsel gebruik om ensiemaktiwiteit van rekombinante gisstamme aan te vul, wat gelei het tot die medeuitdrukking van verskillende ‘cellulases’ en ‘xylanases’ in gelyktydige versuikering en fermentasie SSFs. In die SSFs was daar bevind dat die etanol-produksie omgekeerd proporsioneel is tot substraat konsentrasie, met die laagste etanolopbrengs van 70% wat bereik was in die SSF by ‘n WIS konsentrasie van 10% (w/v). Die uiteindelike proses sal egter 'n eenmalige "gekonsolideerde" bioprosessering (CBP) van lignosellulose na etanol behels, waar die hidrolise en fermentasie van polisakkariede deur' n enkele mikroorganisme of mikrobiese konsortium sonder bygevoegde ‘saccharolytic’ ensieme bemiddel sal word. Die ‘cellulolytic’ gisstamme was in staat om vanself te vermeerder op suikerriet bagasse en gelyktydig alkohol te produseer, al was dit by baie lae titres (0.4 g/L). Hierdie studie bevestig dus dat ‘saccharolytic’ ensieme sinergisme vertoon en dat bagasse 'n potensiële substraat is vir bio-etanol produksie. Daar was ook onder meer bewys dat die konsep van CBP uitvoerbaar is.<br>The National Research Foundation (NRF) for financial support

Master of Science<br>Food Science Institute - Animal Sciences & Industry<br>Sara E. Gragg<br>Food preparation in institutional settings is often carried out in large quantities. Food is cooked and then cooled and stored for later service. Improper or "slow" cooling has been identified by the United States Food and Drug Administration (US FDA) as a contributing factor in foodborne illness outbreaks. This study was designed to test the efficacy of cooling technique combinations on controlling microbial growth within pre-cooked taco meat, chili con carne with beans, low sodium marinara sauce, and brown rice food products. These products were cooked to 73.8°C (165°F) and then portioned to 2 and 3-inch depths in steam table pans. Food product was allowed to cool to 60°C ± 5°C (140°F ± 5°F) before inoculation with surrogate Escherichia coli (E. coli) or Biosafety Level I (BSL I) Bacillus cereus (B. cereus). Pans were uncovered or covered with one or two layers of aluminum foil to allow or restrict air exposure and then placed in a -20°C (-4°F) commercial walk-in freezer or situated in ice water baths in a commercial walk-in refrigerator 4°C (39.2°F). Food products were sampled over a 24-hour period (0, 4, 8, 12, and 24 hour time points) for enumeration of microbial populations. Conclusions from the cooling temperature data in this study revealed uncovered pans and pans stored in the freezer at 2-inch food product depths cooled most rapidly. However, few cooling methods achieved the two-step US FDA Food Code requirement for pre-cooked taco meat, chili con carne with beans, and brown rice products and none of the cooling methods tested achieved the US FDA food code requirement for low sodium marinara sauce. Surrogate E. coli and BSL I B. cereus microbial population data revealed pre-cooked taco meat, chili con carne with beans, and brown rice products all exhibited a certain degree of overall population decline during the 24-hour cooling period. However, a small recovery of surrogate E. coli population was observed in the low sodium marinara sauce product as well as 2-inch product depths of the chili con carne with beans product. This observed growth was less than 0.50 log₁₀ CFU/g, indicating low risk for microbial proliferation from the cooling methods tested. It is possible that the surrogate E. coli and BSL I B. cereus population changes observed were not the result of cooling failure or risk, but rather due to natural variations within the food products. These results indicate all 12 cooling methods tested were low risk and therefore effective at controlling E. coli and B. cereus microbial populations within the four food products.

In todays increased globalized business world and with a firms’ ongoing need for higher quality and lower costs, outsourcing is a popular strategy for companies to use. This thesis intends to study outsourcing in the context of new product development (NPD). The aim of this research is to contribute to the field of operations management. This is achieved by improving the understanding of decision-making during outsourcing NPD by investigating what factors affect the outsourcing decision. This will be fulfilled by addressing the research question What affect the choice between make or buy in outsourcing New Product Development?  By conducting an exploratory single case study and performing semi-structured interviews, the factors that influence decision-making in outsourcing of NPD could be generated. The findings show that competence, time, service, costs, strategy, and ability to collaborate with supplier were important factors that influenced the decision. The factors were analyzed and compared with transaction cost economics and resource-based views, which are theoretical perspectives commonly used to understand the firm’s strategical decisions. The factors from the findings were also used to conduct a cost model and a decision model. This can help a firm’s decision-making and increase the understanding of how the decision in outsourcing of NPD is made.  The results lend support to the argument that outsourcing decisions are complex. With different factors creating different influences, and all of them need to be considered in order to achieve a comprehensive understanding of the decision. The findings also suggest that no theoretical perspective can alone completely explain the decision of outsourcing NPD, they need to be integrated with another demand-oriented perspective. A recommendation for further research should be to investigate how the cost model and decision model could be implemented in practical situations and in different contexts.<br>I dagens globala affärsvärld och företags konstanta strävande efter högre kvalité och lägre kostnader, så är utkontraktering en populär strategi att använda. Denna avhandling avser att studera utkontraktering i samband med ny produktutveckling (PU). Syftet med forskningen är att bidra till området för verksamhetsstyrning genom att förbättra förståelsen i beslutsfattande för utkontraktering av ny produktutveckling genom att undersöka vilka faktorer som påverkar beslutet av att utkontraktera. För att uppfylla detta ska forskningsfrågan Vad påverkar valet mellan att köpa eller göra i utkontraktering av ny produktutveckling? besvaras. Genom att genomföra en explorativ fallstudie och utföra semistrukturerade intervjuer så kan de påverkande faktorerna bakom utkontraktering av PU genereras. Resultatet visade att kompetens, tid, service, kostnad, strategi och förmågan att samarbeta med leverantör är viktiga faktorer att ta hänsyn till vid beslutet. Faktorerna analyserades och jämfördes med transaktionskostnad- och resursbaserad teori som är vanliga teoretiska teorier att applicera för att förstå ett företags strategiska beslut. De framtagna faktorerna användes också gör att konstruera en kostnad- och beslutsmodell som kan användas som stöd och hjälp för företags beslutsfattande och öka förståelsen för hur beslutet av att utkontraktera PU görs.  Resultatet ger stöd till tidigare forskning som menar på att beslutet av att utkontraktera är komplext vilket innebär att flera faktorer påverkar beslutet och alla faktorer behöver bli betraktade för att kunna få en heltäckande förståelse för beslutet. Resultatet visade också på att ingen av de teoretiska perspektiven kan ensamt förklara beslutet av att utkontraktera PU, utan de behöver bli integrerade med ett annat perspektiv för att fullt kunna förklara beslutet. En rekommendation till framtida forskning kan vara att undersöka praktisk tillämpning av kostnadsmodellen och beslutsmodellen och hur de kan användas i andra kontext.

La viabilidad de los tratamientos con radiación ultravioleta (UV-C) a 254 nm como proceso no térmico para la conservación de ovoproductos líquidos fue evaluada desde el punto de vista de la eficiencia en la descontaminación y sus efectos en los atributos de calidad. Los estudios cinéticos sobre la inactivación de microorganismos inoculados y de los principales grupos de microorganismos alterantes sirvieron para discriminar los parámetros más relevantes del tratamiento con UV-C. Los estudios de vida útil sirvieron para evaluar las ventajas aportadas por esta tecnología frente a tratamientos térmicos tradicionales. Las fracciones de huevo (clara, yema y huevo entero) tratadas con UV-C fueron analizadas en cuanto a los cambios de pH, color, estabilidad de lípidos (TBARS, colesterol y valor de peróxidos), efectos en las proteínas (oxidación proteica, DSC, SDS-PAGE), propiedades reológicas (viscosidad dinámica, comportamiento de flujo, viscosidad en función de la temperatura), propiedades funcionales (emulsionantes y espumantes), composición nutricional (vitaminas y minerales), composición de componentes saludables (carotenoides), y cito-genotoxicologia. Finalmente, la aceptación sensorial de los ovoproductos líquidos tratados por UV-C y de productos preparados con ovoproductos líquidos tratados por UV-C (mayonesa, bizcocho y pudin) fueron evaluadas por medio de pruebas triangulares y afectivas. El tratamiento con UV-C demostró ser una excelente alternativa a la pasteurización térmica. En microorganismos inoculados, se demostró una reducción de 5 Log tanto para Gram(+) como para Gram(-) en un equipo comercial para tratamientos en régimen continuo (UVivatec�). En tandas, los resultados también mostraron decrecimientos importantes en el recuento de microorganismos inoculados, aunque serían necesarios tiempos largos de tratamiento para producir una descontaminación comparable a la pasteurización térmica. Los ovoproductos líquidos tratados con UV-C fueron estables durante 8<br>Mendes De Souza, P. (2012). Study of short-wave ultraviolet treatments (UV-C) as a non-thermal preservation process for liquid egg products [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16696<br>Palancia

L'objectif de cette thèse est d'analyser les implications économiques des mesures techniques non tarifaires (MTNT) en vigueur dans les pays développés sur le commerce international de produits agroalimentaires des pays Africains. De façon plus spécifique, elle s'intéresse à trois questions principales. La première, qui est plus générale, est de savoir quel est et qu'est-ce qui détermine l'effet net de l'ensemble des mesures techniques non tarifaires en vigueur dans les pays de l'OCDE sur les exportations Africaines de produits végétaux. La deuxième question, plus spécifique, cherche à savoir quels sont les effets de la conformité aux mesures de limites maximales de résidus (LMR) de pesticides sur la production, l'offre d'exportation et la demande d'importation. Finalement, la troisième question consiste à déterminer quel est l'impact direct des rejets de produits à la frontière des pays Européens du système d'alerte rapide pour les denrées alimentaires et les aliments pour animaux (RASFF) sur les exportations Africaines de fruits et légumes comestibles. Nous traitons ces différentes questions à travers trois essais. Dans le premier essai, nous analysons de façon théorique l'effet net des MTNT sur le commerce bilatéral et proposons une approche empirique robuste pour évaluer cet effet. Ensuite, nous évaluons les effets d'entrave et d'amélioration ainsi que l'effet net des MTNT en vigueur dans les pays de l'OCDE sur les exportations africaines de produits végétaux. Nos résultats théoriques montrent que l'effet net des MTNT sur le commerce bilatéral agrégé dépend non seulement de l'élasticité de substitution et de l'élasticité du coût marginal par rapport aux MTNT, mais aussi du paramètre de forme de la distribution des coûts marginaux qui dépend de la technologie. En plus, nous constatons que pour une élasticité de substitution donnée, seules les entreprises ou les pays caractérisés par un coût marginal inférieur à un coût marginal seuil et une productivité supérieure à un niveau de productivité seuil connaîtront un effet net positif du commerce vers une destination donnée. Pour nos investigations empiriques, nous estimons une équation de gravité sectorielle en utilisant la base de données des MTNT publiée par la CNUCED et le WITS, combinée aux données commerciales transversales pour 2017 de UN COMTRADE/WITS. Les données couvrent 53 pays africains exportant 40 produits végétaux à 4 chiffres du Système harmonisé (SH) vers 35 pays membres de l'OCDE. Nos résultats empiriques montrent à la fois des effets d'entrave (diminution de 3,099%) et d'amélioration (augmentation de 2,056%) des MNT en vigueur dans les pays de l'OCDE sur les exportations africaines de produits végétaux. Ensemble, ces effets produisent un effet net négatif et significatif, ce qui indique que les MNT en vigueur dans les pays membres de l'OCDE constituent des obstacles pour les exportateurs Africains de produits végétaux. Dans le second essai, nous démêlons théoriquement et empiriquement les effets des LMR pour les pesticides sur la production, l'offre d'exportation et la demande d'importation. Nous adoptons une approche de modélisation basée sur les coûts et les bénéfices associés aux normes de sécurité sanitaire des aliments et utilisons notre cadre théorique pour évaluer les effets empiriques nets des LMR de pesticides sur la production de mangues en Afrique et le commerce avec les pays membres de l'OCDE. Théoriquement, nous montrons que les effets des LMR sur la production sont négatifs tandis que leurs effets nets sur le commerce bilatéral peuvent être positifs, nuls ou négatifs selon que l'effet de la qualité perçue par les consommateurs sur la demande d'importation est supérieur, égal ou inférieur à l'effet du coût de mise en conformité sur l'offre d'exportation. Nous utilisons des données transversales pour 12 pays africains qui ont produit et exporté des mangues conformes aux LMR vers 31 pays de l'OCDE en 2016, et nous constatons que, d'une part, les effets nets des LMR de pesticides sur la production de mangues sûres sont négatifs. D'autre part, ils sont positifs sur le commerce des mangues entre les pays africains et les pays membres de l'OCDE. Nos résultats impliquent que le renforcement ou l'imposition de LMR strictes pour les pesticides dans les pays développés peut favoriser les échanges commerciaux alors qu'ils entravent fortement la production dans les pays africains. Dans le dernier essai, nous évaluons l'effet des refus d'importation des pays Européens sur les exportations Africaines de fruits et légumes comestibles, au cours de la période 2008 à 2018. De façon plus spécifique, nous estimons l'effet moyen des rejets aux frontières des pays du réseau RASFF sur les marges extensive et intensive de commerce de fruits et légumes comestibles pour 45 pays africains. Nous utilisons les données sur les rejets aux frontières issues de la base de données en ligne du RASFF avec les données sur les exportations Africaines provenant de la base de données de WITS des Nations Unies. Nous estimons la version canonique de l'équation de gravité sectorielle d'Anderson et al. (2004) en utilisant l'estimateur du Pseudo poisson maximum de vraisemblance (PPML) de Silva et al.(2006) en combinaison avec l'approche robuste d'estimation à deux étapes avec inclusion de résidus (2SRI) de Terza et al.(2008). Nous constatons qu'une augmentation du nombre de refus d'importation par un pays du RASFF une fois dans l'année en cours entraîne une diminution du nombre de partenaires commerciaux en Europe pour les pays africains de 0,018% pour les légumes comestibles et de 0,143 % pour les fruits comestibles. En outre, nos résultats montrent qu'un refus d'importation supplémentaire diminue la valeur des exportations de légumes comestibles des pays africains de 0,045%. Cependant, nous constatons que les refus d'importation des pays du RASFF une fois dans l'année en cours entraînent une augmentation de la valeur des exportations de fruits comestibles des pays africains de 0,126%. Par ailleurs, nos résultats valident explicitement l'hypothèse d'endogénéité du nombre de refus d'importation et mettent en évidence les effets directs et les effets de contagion des rejets aux frontières. Ce dernier résultat signifie qu'une augmentation du nombre de rejets à la frontière d'un produit donné (par exemple un fruit frais) au cours d'une année précédente entraîne une augmentation du nombre de rejets à la frontière pour ce produit et les produits voisins (par exemple un légume frais) au cours de l'année suivante.<br>The objective of this thesis is to analysis the economic implications of technical non-tariff measures (TNTMs) in force in developed countries on the international trade of agricultural and agri-food products of African countries. More specifically, we focus on three main issues. The first more general question is: what is and what determines the net effect of the set of TNTMs in OECD countries on African exports of plant products ? The second, more specific, question is: what are the effects of compliance with maximum residue limit (MRL) for pesticide on production, export supply and import demand ? Finally, the third question is to determine: what is the direct impact of product rejections at the border of European countries of the Rapid Alert System for Food and Feed (RASFF) on African exports of plant products ? We address these different questions through three essays. In the first essay, we theoretically analyze the net effect of technical non-tariff measures (TNTMs) on bilateral trade and suggest a robust empirical approach to evaluate this effect. We assess the impediment, enhancement and net effects of the TNTMs in force in OECD countries on African exports of plant products. Our theoretical findings highlight that the net effect of the TNTMs on aggregate bilateral trade depends not only on the elasticity of substitution and the elasticity of marginal cost with respect to the TNTMs but also the shape parameter of the distribution of marginal costs which depends on the technology. In addition, we find that for a given elasticity of substitution, only firms or countries characterized by a lower marginal cost than a cutoff marginal cost and higher productivity than a threshold productivity level will experience a positive net effect of trade to a given destination. For our empirical investigation, we estimate a sectoral gravity equation using the non-tariff measures (NTMs) database released by UNCTAD and WITS combined with cross-sectional trade data for 2017 from the UN COMTRADE/WITS database. The data cover 53 African countries exporting 40 Harmonized System (HS) 4-digit plant products to 35 OECD member countries. Our empirical results show both impediment (decrease of 3.099%) and enhancement (increase of 2.056%) effects of the TNTMs in force in OECD countries on African exports of plant products. Together, these effects yield a negative and significant net effect, which indicates that the TNTMs in force in OECD member countries are obstacles for African exporters of plant products. In the second essay, we disentangle theoretically and empirically the effects of the MRLs for pesticides on the production, export supply and import demand. We adopt a modelling approach based on the costs and benefits associated with food safety standards and use our theoretical framework to assess the empirical net effects of the MRLs for pesticides on African mango production and trade with OECD member countries. Theoretically, we show that the production effects of MRLs are negative while their net effects on bilateral trade can be positive, zero or negative depending on whether the consumers' perceived quality effect on import demand is greater than, equal to or less than the compliance cost effect on export supply through the unconditional expected standard-compliant production. We use a cross-sectional data set for 12 African countries that produced and exported MRL-compliant mangoes to 31 OECD countries in 2016, and find that, on the one hand, the net effects of MRLs on the production of safe mangoes are negative. On the other hand, they are positive on mango trade between African and OECD member countries. Our results highlight that the tightening or imposition of strict MRLs for pesticides in developed countries may be trade promoting while they severely impede production in African countries. In the last essay, we assess the effects of European countries' import refusals on African exports of edible vegetables and fruits from 2008 to 2018. We specifically estimate the average effects of the RASFF countries' border rejections on the extensive and intensive margins of African countries exports of edible vegetables and fruits. We use the border rejections data from the RASFF online database and export data on 45 African countries from the UN WITS database. We estimate the canonical version of the sectoral gravity equation of Anderson and al. (2004) using the Poisson pseudo maximum likelihood (PPML) estimator of Silva and al. (2006) in association with the robust twostage residual inclusion (2SRI) approach of Terza and al. (2008). We find that a single increase in the number of import refusals by a RASFF country in the current year leads to a decrease in the number of trade partners in Europe for African countries by 0.018 percent for edible vegetables and 0.143 percent for edible fruits. In addition, our results show that one additional import refusal decreases the export value of African countries' edible vegetables by 0.045 percent. However, we find that RASFF countries' refusal to import once in the current year leads to an increase in the export value of African countries' edible fruit by 0.126 percent. Furthermore, our results explicitly validate the hypothesis of the endogeneity of the number of import refusals and highlight both the direct and spillover effects of border rejections. The latter result means that an increase in the number of border rejections for a given product (for instance, a fresh fruit) in a given year leads to an increase in the number of border rejections for a product and its neighboring products (for instance, a fresh vegetable) in the next year.

Thesis (MScFor)--Stellenbosch University, 2004.<br>ENGLISH ABSTRACT: This research focuses on the utilisation of de-inking sludge from a tissue mill to produce a wood-fibre inorganic composite called the Deviro panel. The study is based on the SA provisional patent 95/9594 by Ysbrandy and Gerischer' and the further research conducted by Crafford'. The patented Deviro panel contains up to 70% de-inking sludge. Cement and a cement extender serve to fortify the composite. The panel's fibre content of 25-30% is significantly greater than encountered in commercial fibre inorganic composites which contain 8-12% fibre by weight. The physico-mechanical characteristics of the Deviro panel compare favourably with resin bonded wood-fibre composites, but less favourably compared to conventional wood and wood-fibre inorganic composites. These properties are strongly dependent on panel density. For instance flexural strength being directly proportional while dimensional stability and hygroscopicity being inversely proportional to density. After confirming the results from the preceding work by Crafford, further improvements were investigated through chemical and curing enhancements. For instance, an autoclaving treatment during the curing period showed an increase in flexural strength. Addition of water glass could be associated with bulking of the panel, which resulted in increased flexural strength and a slight reduction of density. Panel density could be significantly reduced by the addition of Perlite, while inhibiting the concomitant reduction in strength. In addition a pilot production process was developed to produce 1m2 panels, which exhibited similar curing characteristics as the smaller panel units.<br>AFRIKAANSE OPSOMMING: Hierdie navorsing handeloor die gebruik van ontinkingsslyk van 'n sneespapier meule om die Deviro paneel, 'n houtvesel anorganiese saamgestelde produk, te produseer. Die studie volg uit die SA voorlopige patent 95/9594 deur Ysbrandy en Gerischer en verdere narvorsing deur Crafford'. Die gepatenteerde Deviro paneel bevat tot 70% ontinkingsslyk. Sement en sement-byvoegmiddels dien om die saamgestelde produk te versterk. Die paneel bevat 25-30% vesel wat aansienlik meer is as ander kommersiële anorganiese saamgestelde produkte wat 'n vesel inhoud van 8-12% het. Die megamese eienskappe van die Deviro paneel is vergelykbaar met houtvesel saamgestelde produkte waar hars as kleefiniddel dien, maar vergelyk minder gunstig teenoor konvensionele hout en houtvesel anorganiese saamgestelde produkte. Die paneel se eienskappe is afhanklik van sy digtheid Buig sterkte is eweredig terwyl dimensionele stabiliteit en hygroskopisiteit omgekeerd eweredig aan die digtheid van die paneel is. Die voorafgaande werk van Crafford is eers gestaaf voordat veranderinge aan die chemiese samestelling en drogingsmetodes van die paneel nagevors is. Daar is byvoorbeeld bevind dat, deur die paneel te outoklaveer gedurende die set periode, dit lei tot 'n toename in buig sterkte. Die byvoeging van water glas kan swelling laat plaasvind wat 'n afname in buig sterkte en 'n afname in digtheid tot gevolg het. Digtheid kan ook aansienlik verlaag word deur die byvoeging van Perlite terwyl 'n dienooreenkomstige verlaging in buig sterkte tot 'n mate voorkom word. 'n Loods produksie proses is ook ontwikkel om 'n 1m2 paneel te vervaardig wat dieselfde eienskappe toon as die kleiner paneel.

In Bacillus subtilis, genetic competence, sporulation and antibiotic production are controlled by quorum-sensing global regulatory mechanism. Bacilysin, being produced and excreted by certain strains of Bacillus subtilis, is a dipeptide antibiotic composed of L-alanine and L-anticapsin. We showed that the biosynthesis of bacilysin is under the control of quorum sensing global regulatory pathway through the action of ComQ/ComX, PhrC (CSF), ComP/ComA in a Spo0K (Opp)-dependent manner. Recently, the ywfBCDEF genes of B. subtilis 168 were shown to carry biosynthetic core function and renamed as bacABCDE operon. The objective of the present study is to elucidate the effects of previously-identified genes srfA, oppA, comA, phrC, phrF, phrK, comQ (comX), comP, spo0H, spo0A, abrB and codY on the expression of bacilysin biosynthetic operon bacABCDE. In order to monitor the expression of bac operon a B. subtilis strain, namely OGU1, containing a transcriptional bacA-lacZ fusion at bacA locus was constructed. Subsequently, each of the above-mentioned genes of cell density signaling was insertionally inactivated by transforming the competent cells of OGU1 with chromosomal DNA of the corresponding blocked mutant strains. The resulting strains and OGU1 as the control were cultured in PA medium and bacA-directed &amp<br>#946<br>-galactosidase activities were monitored. bacA-lacZ expression was severely impaired in the srfA, oppA, comA, phrC, phrF, phrK, comQ (comX), comP, spo0H and spo0A disrupted mutants. On the other hand, in the abrB single mutant bacA expression level increased nearly 2-fold during exponential growth and in the codY mutant it severely decreased during the stationary phase.

The purpose of this study is to explore and elaborate how firms are managing aesthetic with color and design choice as open innovation practice and explore its applicability in various sectors.  Two research questions are addressed: How is aesthetics with color and design choices managed by firms using open innovation practices? Can aesthetics with color and design choices be managed as open innovation practices for all kinds of technical designed products?   The study is based on a case study combined with survey method which constitutes a combination of quantitative and qualitative research for conducting productive research. In order to analyze and explain the case study as open innovation practice for designed technical products, the 4P model of innovation, open innovation model, product design process, digital prototyping and virtual customer environment are used. The survey was used for analyzing the question on generalization for all other designed technical products.   The study shows that some mobile firms are using “theme creator”, software for themes that is used for inside aesthetics of designed technical products with customer collaboration and participation. Sony Ericsson is one firm that is establishing activities for outlook aesthetics and inside aesthetics with color and design choice for its designed technical product (mobile). These activities are interpreted as open innovation practices conducted in virtual customer environment by Sony Ericsson. The survey result shows the customer’s willingness for participation and customer’s demand for the change in color and design of designed technical products by their own choice. When combining the case study and survey results it is concluded that color and design choice is required to improve aesthetics for designed technical products.

Background Broth microdilution (BMD) is a gold-standard reference method to determine minimum inhibitory concentration (MIC) of antibiotics. For this, a standardized concentration of bacterial inoculum (2e5–8e5 colony-forming units, CFU/ml) is added to progressively higher concentrations of antibiotics. Bacteria stop growing at a particular antibiotic concentration termed MIC. Like other assays, various biological and/or technical factors can affect BMD results.   Aims To investigate the effects of inoculum concentration (5e4–5e6 CFU/ml), growth-medium concentration (cation-adjusted Mueller-Hinton Broth (CAMHB)), ranging 0.5x to 2x (1x as standard)) and age (&lt;6-months or &gt;1-year old) of fastidious medium on MIC results. And to compare BMD results using 5 different brands of CAMHBs and 1 cation-non-adjusted MH-broth (non-CAMHB).   Methods 12 isolates of bacteria (gram-positive (n=3), gram-negative(n=5), fastidious isolates (n=7)) and custom-made antibiotics-containing plates for gram-positive (11 antibiotics) or gram-negative bacteria (10 antibiotics) were used. Overnight-grown colonies were used to prepare BMD solutions (MH-broth + inoculum +/- fastidious) which were plated on antibiotic-plates as well as diluted prior to plating on agar-plates. Antibiotic- and agar-plates were incubated (18–20hr, 35°C) and used to determine MICs (following European Committee on Antimicrobial Susceptibility Testing instructions) and actual number of viable bacteria in BMD solutions, respectively.   Results Increasing inoculum concentration increased MICs of all antibiotics except cefoxitin. Piperacillin–tazobactam, levofloxacin, benzylpenicillin and ampicillin were especially sensitive to increase in inoculum and showed a 4-fold increase in &gt;50% isolates. MICs for tobramycin, tigecycline and gentamicin increased by 2-fold in &gt;50% isolates every time MH-broth concentration increased. Age of fastidious medium had no decipherable pattern of effects on MIC. All MH-broths gave similar results except when testing daptomycin which gave higher MICs with non-CAMHB compared to CAMHB.    Conclusion This research reveals some technical factors affecting MIC results. These results could help define parameters for automated BMD-performing-systems. However, this research shows only trends as more replicates are needed to determine statistically significant results.

Thesis (Ph. D.)--Ohio State University, 2005.<br>Title from first page of PDF file. Document formatted into pages; contains xiii, 137 p.; also includes graphics (some col.). Includes bibliographical references (p. 133-137). Available online via OhioLINK's ETD Center

The genes encoding the acetate kinase and phosphotransacetylase enzymes from <i>Methanosarcina thermophila</i> were isolated from a genomic library on a fifteen kilobase fragment The genes are located adjacent to one another, with the phosphotransacetylase gene (<i>pta</i>) directly upstream of the acetate kinase gene (<i>ack</i>). The two genes were sequenced, along with a third Open Reading Frame (designated <i>orfY</i>). The <i>orfY</i> gene appears to encode a novel protein whose physiological function has yet to be determined.<br>Ph. D.

Orientador: Sergio Tonini Button<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica<br>Made available in DSpace on 2018-08-05T06:48:27Z (GMT). No. of bitstreams: 1 Pinardi_EmersonRoberto_M.pdf: 2980822 bytes, checksum: d3b98a4a8570258311e79f8b2c9806f5 (MD5) Previous issue date: 2005<br>Resumo: O objetivo desse trabalho é otimizar as fases de desenvolvimento de produto buscando reduzir principalmente o tempo e os custos envolvidos nas mesmas. Como o desenvolvimento é uma atividade muito ampla, que pode ser dividido basicamente em cinco fases: planejamento, desenvolvimento do projeto, desenvolvimento do processo, manufatura, melhoria contínua. Esse trabalho concentrou-se na fase de projeto, mais especificamente no processo de distribuição de desenho de produto gerado na Engenharia, o qual é utilizado em diversos setores das unidades fabris. O desafio foi gerar um sistema informatizado para distribuição do desenho de produto, o qual pode ser gerado a partir de 4 sistemas de CAD diferentes dependendo da disponibilidade de sistema e qual a interface necessária para atender o cliente. Após a criação do novo sistema de distribuição de desenho, comparou-se com a metodologia convencional aplicada até então, baseada em cópia de papel e distribuição via correio interno, indicando os ganhos e os possíveis inconvenientes surgidos. Os resultados obtidos mostram como essa nova metodologia de distribuição de desenho informatizado diminuiu os gastos com a geração de cópias, o tempo de trânsito da informação, bem como a facilidade de acesso à mesma<br>Abstract: The objective of this work is optimize the phases of product development, reduce the main time and the cost involved in itself. Like the development is a wide activity, that can be divided in five basic phases: planning, development of project, development of process, manufacturing, continued increase. Emphasized only in project phase, to increase the specific process of distribution of product drawing made by Engineering, and itself is utilized in many departments of the several units the same company. The challenge was create a computer system to distribution of drawing product, itself can be made in four different CAD systems as according as availability the system and which interface were necessary to attend the customer. After made the new system of drawing distribution, compared with a conventional methodology applied nowadays, which was based in paper copy and distribution by internal mail, showing the profit and the possible inconvenience that could happen. The results show like this new methodology to distribution of electronic drawing lows the cost with the copy drawing, time of the information circulate, and the facility to access electronic drawings<br>Mestrado<br>Materiais e Processos de Fabricação<br>Mestre em Engenharia Mecânica

У технологічному процесі вхідного контролю матеріалів виникає задача розпізнавання зображень, одержаних у рентгенодефектоскопії. Тому актуальною є задача створення автоматизованої системи підтримки прийняття рішень (СППР) для контролю та діагностування технічних виробів. Розглянемо результати застосування інформаційно- екстремальної інтелектуальної технології для проектування здатних навчатися СППР для перевірки сортності металів за їх рентгенограмами. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/25237

In this study, strains of probiotic bacteria have been selected for tolerance to low pH, bile, sucrose, oxygen in media and low storage temperatures. Lactobacillus acidophilus 2401 and Bifidobacterium infantis 1912 were selected as strains able to survive in these conditions. These two strains were then offered further protection from the adverse conditions of food processing and storage by microencapsulation in a calcium alginate and starch gel matrix. Encapsulation in calcium alginate increases survival in yoghurt. In cheddar cheese the free L. acidophilus 2401 and B. infantis 1912 cells survived better than the encapsulated cells, probably due to the dense nature of the cheddar cheese matrix combined with the encapsulation restricting the flow of the nutrients and metabolites between the outside environment and the cells. In ice cream survival was high, probably due to the high fat and solids nature of the ice cream combined with the low storage temperature. The trial results of the laboratory scale production was consistent with the survival results for yoghurt and cheddar cheese. Incorporation of encapsulated probiotic bacteria into ice cream and cheddar cheese was acceptable by sensory standards and largely unnoticeable in comparison with the same foods without capsules. The capsules were visible and able to be felt on the tongue when eaten in yoghurt causing the product to be disliked by the panellists.<br>Master of Science (Hons)