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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The effect of Agnus castus D3 on menopausal symptoms

Lazarus, Kerri Leigh 19 June 2014 (has links)
M.Tech. (Homoeopathy) / Please refer to full text to view abstract
22

The Efficacy of Nanoemulsion-Based Delivery Systems to Improve Vitamin D3 Bioaccessibility and Bioavailability

Kadappan, Alagu Selvi 02 July 2019 (has links)
Vitamin D deficiency is an epidemic issue in all age groups in Western countries and that affects both skeletal and non-skeletal functions. Even with the wide application of food fortification, vitamin D deficiency tends to increase continuously. Being hydrophobic in nature, vitamin D has poor solubility; thereby it negatively affects its absorption and bioavailability when compared to other hydrophilic dietary compounds. The need to develop a novel strategy is of greater importance to enhance its bioavailability and thereby improving vitamin D level in the body. In this study, lipid-based delivery of oil-in-water nanoemulsion (diameter < 200nm) was utilized to improve the bioaccessibility and oral bioavailability of vitamin D3. First, we examined the in vitro relative bioaccessibility of nanoencapsulated vitamin D3 using a simulated gastrointestinal system. The study results showed that nanoemulsion-based delivery system significantly increased the relative bioaccessibility by 3.94 fold when compared to the coarse emulsion (diameter >200nm), as indicated by the concentration of vitamin D3 in the mixed micelles. To evaluate the in vivo bioavailability of vitamin D3 an animal study was conducted. Mice were assigned randomly to three groups: vitamin D3 nanoemulsion (n=6), coarse emulsion (diameter > 200nm) (n=6) and vehicle (nanoemulsion without vitamin D3) (n=3), which is the control group. After 3-days of feeding emulsion by mixing in drinking water, the serum 25(OH)D3, a biomarker of vitamin D availability, was measured using immunoassay. We found that serum 25(OH)D3 level in animals fed with vitamin D3 nanoemulsion was significantly higher than in those animals fed with coarse emulsion (22.7 ± 1.10 ngmL-1 vs 17.92 ± 2.82 ngmL-1). It indicated that nanoemulsion improved the in vivo bioavailability by 28%. These results showed that the nano-based delivery systems can be utilized to improve vitamin D level, and further human studies are warranted for its application to the human population in order to improve the vitamin D status.
23

Die Expression des Vitamin-D-Rezeptors und der 24-Hydroxylase in Knochenmetastasen unterschiedlicher Entität / Vitamin-D-receptor- and CYP24A1- expression in bone metastases of different primary origin

Seiler, Jonas January 2023 (has links) (PDF)
Knochenmetastasen sind unter den drei häufigsten Manifestationsorten metastatischer Absiedelungen von fortgeschrittenen Tumorerkrankungen. Dabei sind insbesondere Patientinnen und Patienten mit Prostata- und Mammakarzinom von Knochenmetastasen betroffen. Diese Knochenmetastasen führen häufig zu einer deutlichen Verschlechterung der Lebensqualität und zu einer Begrenzung der Therapieoptionen auf lediglich palliative Ansätze. Die biologisch aktive Form von Vitamin D3, 1,25(OH)2-Vitamin D3, zeigt in präklinischen Studien antiproliferative und differenzierende Effekte auf Tumorzellen (101, 102, 104), die haupsächlich durch die Bindung an den Vitamin D-Rezeptor (VDR) vermittelt werden. Darüberhinaus konnte präklinisch gezeigt werden, dass eine niedrige Expression des VDRs, ligandenunabhängig, die Knochenmetastasierung und das Tumorwachstum begünstigt (118). Eine niedrige VDR-Expression ist in Primärtumoren in klinischen Studien mit aggressiven Tumoreigenschaften assoziiert (111, 113, 115) und kann zudem mit einer erhöhten/früheren ossären Metastasierung einhergehen (167). Zudem gibt es Hinweise auf einen dysregulierten 1,25(OH)2-Vitamin D3-Katabolismus durch eine erhöhte Expression des 1,25(OH)2-Vitamin D3 katabolisierenden Enzyms CYP24A1/24-Hydroxylase in primärem Tumorzellen (70, 121, 122). Durch die Untersuchungen der Primärtumoren ist damit zu hypothetisieren, dass die Expression des VDRs und von CYP24A1 bei der Tumorprogression und Knochenmetastasierung von Bedeutung sein könnte. Entsprechende Untersuchungen des VDRs und der 24-Hydroxylase in Knochenmetastasen fehlen allerdings. Deshalb wurde in dieser Arbeit die Expression des VDRs und von CYP24A1 in Knochenmetastasen unterschiedlicher Primärtumoren von 66 Patientinnen und Patienten untersucht und mögliche Assoziationen mit aggressiven Tumoreigenschaften analysiert. Der VDR konnte sowohl im Zytoplasma als auch im Nukleus nachgewiesen werden, während CYP24A1 nur im Zytoplasma lokalisiert war. Dabei wiesen insgesamt 71 % der Knochenmetastasen eine hohe VDR-Expression im Nukleus und 56 % im Zytoplasma auf. 59 % der Knochenmetastasen wiesen eine hohe Expression des VDRs insgesamt auf. CYP24A1 war ebenso in 59 % der Knochenmetastasen hoch exprimiert. Bei der Auswertung des Zusammenhangs zwischen den TNM-Stadien und des Gradings zeigte sich ein nicht signifikanter Trend von schlecht differenzierten Tumoren hin zu einer niedrigeren nukleären VDR-Expression (p=0.07, siehe Abbildung 33). Bezüglich der T-Stadien zeigten sich keine Unterschiede der Expression des VDRs und von CYP24A1 in den Knochenmetastasen zwischen lokal fortgeschrittenen und kleinen Primärtumoren. Weiterhin hatten Patientinnen und Patienten mit Lymphknotenmetastasen tendenziell eine verminderte VDR- und auch CYP24A1-Expression in den Knochenmetastasen im Vergleich zu Patienten und Patientinnen ohne Lymphknotenmetastasen (pVDR=0.15, pCYP24A1=0.06, siehe Abbildung 35). Außerdem hatten Patientinnen und Patienten mit multiple metastasierten Tumoren eine signifikant niedrigere nukleäre VDR- und auch CYP24A1-Expression im Vergleich zu Patientinnen und Patienten mit ausschließlich ossärer Metastasierung (pVDR=0.03, pCYP24A1=0.01, Abbildung 36). Die Proteinexpression des VDRs- und von CYP24A1 korrelierten signifikant (p=0.001). Somit konnte mit dieser Arbeit die Proteinexpression des VDRs und von CYP24A1 in Knochenmetastasen durch Immunhistologie nachgewiesen werden. Insgesamt wurde der VDR und CYP24A1 von Knochenmetastasen diverser Entität unterschiedlich stark exprimiert. Jedoch könnten insbesondere Patienten mit VDR-exprimierenden Knochenmetastasen von einer Vitamin D3-Supplementierung profitieren, die häufig einen 25-OH-Vitamin D3 Mangel zeigen (165, 166). Ebenso könnte eine Untersuchung auf einen niedrigen VDR-Status in Primärtumoren dabei helfen, Krebspatienten mit einem hohen Metastasierungsrisiko zu identifizieren. Allerdings sind weitere und größere Studien inbesondere mit Evaluation des gesamten Vitamin D-Metabolismus und -Signalwegs notwendig, um diesen Zusammenhang weiter zu untersuchen. / Bone metastases are among the three most frequent sites of metastatic manifestation of late-stage cancers, particularly of prostate and breast cancers. Bone metastases often reduce patient’s quality of life due to skeletal-related events. Additionally, bone metastatic tumor treatment is predominantly restricted to palliative measures. In preclinical studies, the biologically active form of vitamin D3, 1,25(OH)2-vitamin D3, has been demonstrated to have antiproliferative and differentiating effects on cancer cells (101, 102, 104), which are mostly mediated by binding to the vitamin D receptor (VDR). Moreover, the VDR expression itself may affect cancer growth and the metastatic potential to bone. For example, preclinically, it has been shown that VDR knockdown promotes bone metastases manifestation and growth (118). Furthermore, low VDR expression is associated to aggressive cancer characteristics in primary cancers (111, 113, 115) and also linked to earlier bone metastasis manifestation in breast cancer (120). In addition, there is evidence that 1,25(OH)2-vitamin D3- catabolism is altered in cancer cells. Thus, inactivation of local 1,25(OH)2-vitamin D3-levels in cancer cells may be increased (70, 121, 122). VDR and CYP24A1 expression could therefore be important concerning cancer progression and bone metastases manifestation and growth. However, there are currently no reports of studies investigating VDR expression and vitamin D-metabolism in bone metastases. The aim of this study was hence to assess VDR and CYP24A1 (vitamin D-catabolizing enzyme) expression in bone metastases of 66 patients secondary to prostate-, breast-, kidney-, lung-, follicular thyroid- and colorectal cancers using immunohistochemistry (132). While the VDR was localised in the nucleus and cytoplasm, CYP24A1 was identified in the cytoplasm only. A high VDR nuclear protein expression was detected in 47/66 (71 %) and cytoplasmatic in 37/66 (56 %). 39/66 (59 %) of bone metastases had a high total VDR expression. CYP24A1 was also strongly expressed in 39/66 (59 %) of bone metastases. Expression levels were correlated to patient data and cancer characteristics. There was a non-significant trend of high-grade cancers towards low nuclear VDR expression (p=0.07, see figure 33). Additionally, patients with lymph node metastases (N-stage) tended to have a reduced bone metastatic VDR and CYP24A1 expression compared to patients without lymph node metastases (pVDR=0.15, pCYP24A1=0.06, see figure 35). There was no difference of VDR and CYP24A1 expression in bone metastases between locally advanced and small primary cancers (T-stage). Interestingly, patients with further metastases other than bone metastases had reduced nuclear VDR and CYP24A1 levels compared to patients without other distant metastases (pVDR=0.03, pCYP24A1=0.01, see figure 36). Nuclear VDR and CYP24A1 expression showed a significant positive correlation (p=0.001). In conclusion, this study demonstrated that the VDR and CYP24A1 are widely expression in bone metastases of various origin. Therefore, patients with VDR-expressing bone metastases could, in particular, benefit from vitamin D3-supplementation, as vitamin D deficiency is frequent in patients with bone metastases (165, 166). Additionally, screening for a low VDR status in primary cancers could help to identify cancer patients at a high risk of metastasis. However, further and larger studies, that evaluate the entire vitamin D metabolism and signalling pathway, are needed to investigate this association.
24

Percepce dopadů dálnice D3 představiteli obcí / Perception of D3 motorway impacts by municipal representatives

Vrtiška, Miroslav January 2015 (has links)
Perception of D3 motorway impacts by municipal representatives Abstract The thesis analyzes in detail the perception of the impact of D3 motorway by the representatives of the affected municipalities, who represent three different parts of society - community leaders, a representative of business and general population. The expected impacts of a new motorway in the given area are discussed with technical bibliography, which provided the basis for research questions and hypotheses. Field research was conducted in municipalities, which will yet be affected by the planned D3 motorway, and in municipalities in Central and Southern Bohemia, where part of D3 motorway had already been completed. Semi-structured interviews and questionnaires were used as the main research tools. The finding about the perception of the D3 motorway in the affected municipalities were based on detailed analysis of statistical data and in-depth analysis of the interviews. The findings show that the resulting perception of the impact varies depending on various aspects like geographical aspects, such as the location of the village (with regard to the highway route) or the population size of the municipality. Generally speaking, the motorway is positively perceived by municipalities that are currently substantially burdened by heavy...
25

Encapsulação de colecalciferol (vitamina D3) por spray chilling / Encapsulation cholecalciferol (vitamin D3) by spray chilling

Paucar, Orfa Collazos 26 February 2016 (has links)
A indústria de alimentos está constantemente desenvolvendo produtos que fornecem, além de nutrientes, benefícios adicionais à saúde, tais como os enriquecidos com vitaminas. A vitamina D3 (colecalciferol) é sintetizada na pele durante a exposição da luz solar, controla a homeostase de cálcio e fósforo, metabolismo ósseo, pressão arterial e reabsorção renal de cálcio. O processo de microencapsulação vem sendo bastante aplicado em alimentos e um dos objetivos principais é o controle da liberação do agente ativo no momento e local desejado. A tecnologia de spray chilling é interessante para a microencapsulação de vitaminas lipossolúveis. O objetivo deste trabalho foi microencapsular vitamina D3, utilizando o método de spray chilling para a produção das micropartículas lipídicas sólidas (MLS). Para produção das MLS utilizou-se gordura vegetal com ponto de fusão em torno de 48 °C como carreador. Três tratamentos foram estabelecidos: sem aditivos (T1), com adição de 1% de cera de abelha (T2) e com 1% de lecitina de soja (T3). As micropartículas foram caracterizadas quanto à morfologia por microscopia eletrônica de varredura, tamanho médio por difração a laser, espectroscopia no infravermelho por transformada de Fourier (FTIR) e foi analisada a estabilidade da vitamina D3 durante o armazenamento a 10 e 25 °C, por meio de quantificações periódicas em cromatografia líquida de alta eficiência (CLAE). As micropartículas obtidas foram esféricas, semelhantes morfologicamente e com distribuição monocaudal de partículas. O tamanho médio das partículas variou em função dos seus ingredientes, sendo que as micropartículas produzidas apenas com vitamina e gordura foram menores em relação às demais (83,0% < 100 &micro;m). A espectroscopia na região do infravermelho (FTIR) demonstrou que não ocorreu interação entre os ingredientes. A estabilidade da vitamina D3 encapsulada foi satisfatória ao longo de 65 dias com valores superiores a 87% para os três tratamentos e a temperatura apresentou influência na estabilidade. As MLS produzidas com cera apresentaram melhores resultados de estabilidade de vitamina D3 com valores de 90,18 ± 2,23 % após 65 dias de estocagem. Esses resultados são promissores e demostram a viabilidade da técnica de spray chilling na produção de MLS carregadas de vitamina D3, possibilitando uma futura aplicação em alimentos. / The food industry is constantly developing products that provide, in addition to nutrients, additional health benefits such as enriched food with vitamins. Vitamin D3 (cholecalciferol), which is synthesized in the skin during exposure of sunlight, controls the homeostasis of calcium and phosphorus, bone metabolism, blood pressure and renal reabsorption of calcium. The microencapsulation process has been widely applied in food and is a key objective to control the release of active agents at specific time and desired location. The spray chilling technology is interesting for microencapsulation of fat-soluble vitamins. The objective of this work was microencapsulating vitamin D3 using the spray chilling method for the production of solid lipid microparticles (SLM). For the production of the SLM it was used vegetable fat with melting point around at 48 °C as a carrier. Three treatments were established: no additives (T1), 1% of beeswax (T2), and 1% soybean lecithin (T3). The morphology of microparticles was characterized by scanning electron microscopy, laser diffraction (average size) and Fourier transform infrared spectroscopy (FTIR). Additionally, vitamin D3 stability was examined during storage at 10 and 25 °C, through periodic measurements by High-performance liquid chromatography (HLPC). The microparticles obtained were spherical with similar morphology and unimodal size distribution. The average particle size varied according to composition wherein microparticles produced with vitamin and fat were lower than other (83.0% of particles smaller than 100 &micro;m). Spectroscopy in the infrared (FTIR) showed that there was no interaction between the components. The stability of vitamin D3 encapsulated was satisfactory over 65 days with values greater than 87% for the three treatments and temperature have any influence on the stability. The SLM produced with wax showed better stability for vitamin D3 with values of 90.18 ± 2.23% after 65 days of storage. These results are promising and demonstrate the feasibility of spray chilling technique in the production of SLM loaded with vitamin D3, allowing future application in foods.
26

Design and implementation of a timeline for the Web

Jansson, Tobias January 2015 (has links)
Visuzalizing time information using a timeline has been done for over 250 years. Using a timeline can assist users in making sense of time data which could otherwise be hard to understand. A timeline has been implemented at Ida Infront, and its purpose is to help managers understand how cases are progressing in a case management system created by Ida Infront. The timeline is designed using usability methods and has been evaluated with regards to its usability and how it interacts. Results show that there are a number of things that can increase usability and add meaningful interaction, such as using icons to collect similar data into one point and adding filtering capabilities so that users can find interesting data faster.
27

The effect of developmental vitamin D3 deficiency on brain development, behaviour and immune function in the Sprague-Dawley rat

Louise Harvey Unknown Date (has links)
Epidemiological evidence from season of birth and migrant studies has led to the proposal that developmental vitamin D3 (DVD) deficiency may be a risk factor for schizophrenia. Concurrently, there has been recent intense interest in vitamin D3 as a modifying factor in the development of immune responses. However, the effects of DVD deficiency on immune function remains unknown. Thus, a model of DVD deficiency has been developed in Sprague-Dawley rats. Briefly, female rats were maintained on a vitamin D3 deficient diet prior to and during gestation. At birth dams were returned to a vitamin D3 replete diet. Post-weaning their offspring, the DVD-deficient rats, were maintained on a vitamin D3 replete diet. Therefore, this model represents a transient, prenatal vitamin D3 deficiency. A number of structural and cellular changes have been described in the DVD-deficient rat brain, including ventriculomegaly, decreased growth factor expression, and increased rates of mitosis. These changes are correlated with altered adult behaviour in the DVD-deficient rat, including a locomotor sensitivity to novelty. This thesis will focus on extending these findings and characterising immune function in the DVD-deficient rat. Vitamin D3 can affect cellular differentiation and is anti-proliferative and pro-apoptotic in many tissues including the brain. The effect of DVD deficiency on brain development has been restricted to neuronal cells in vivo and in vitro. However, the effect of this exposure on glial cell maturation and phenotype was unknown. The experiments reported in this thesis demonstrated that primary cortical glial cell cultures from DVD-deficient rat neonates displayed a similar phenotype and maturational status compared with cells from control rats. Learning and memory was examined in this model by exploring the phenomenon of latent inhibition. DVD-deficient rats displayed normal latent inhibition, however, they exhibited a subtle performance acquisition deficit during the early stages of the conditioned avoidance learning task. Extended handling and pre-exposure were able to ameliorate this deficit, though with this treatment normal latent inhibition was also abolished in both control and DVD-deficient rats. Ultrasonic vocalization and nociceptive threshold testing confirmed that alterations in peripheral sensation could not explain this performance acquisition deficit. The results suggested that anxiety or attentional mechanisms may have contributed to this rate of learning deficit. Finally, as vitamin D3 is a powerful immunoregulator, there is the potential for a transient DVD deficiency to induce a persistent alteration in the development and function of the immune system. This hypothesis was supported by findings that showed DVD deficiency resulted in a primed immune system, as indicated by an enlarged spleen, thymus and peripheral lymph tissue as well as increased pro-inflammatory cytokine production in response to an in vitro stimulation. However, these findings did not lead to an alteration in cell mediated immune response in vivo. The results from the research reported in this thesis indicate that a transient, prenatal vitamin D3 deficiency had a subtle yet significant effect on the immune system and behaviour of the adult rat. These findings add further weight to the body of evidence that link prenatal vitamin D3 status to various adverse health outcomes. The DVD-deficient rat model is an integral step in understanding prenatal vitamin D3 deficiency as a potential environment risk factor in the development of immune and psychiatric disorders.
28

Características ósseas de frangos de corte suplementados com Solanum glaucophyllum

Drosghic, Laura Caroline Almeida Branco 30 March 2015 (has links)
Submitted by Jordan (jordanbiblio@gmail.com) on 2017-02-20T16:55:45Z No. of bitstreams: 1 DISS_2015_Laura Caroline Almeida Branco Drosghic.pdf: 1024901 bytes, checksum: 769c0ac66d67204071d5db39a72654cd (MD5) / Made available in DSpace on 2017-02-20T16:55:45Z (GMT). No. of bitstreams: 1 DISS_2015_Laura Caroline Almeida Branco Drosghic.pdf: 1024901 bytes, checksum: 769c0ac66d67204071d5db39a72654cd (MD5) Previous issue date: 2015-03-30 / CAPES / A produção de aves sempre buscou maximizar a eficiência produtiva de frangos de corte, mas associadas a essas melhorias surgiram características indesejadas. Os transtornos ósseos são ocasionados pela rápida deposição de tecido animal, ao mesmo tempo em que o desenvolvimento ósseo continuou com crescimento normal. Isso fez com que houvesse prejuízo à capacidade de deslocamento, ao bem estar e, consequentemente ao desenvolvimento destas. Surgiram inúmeros programas nutricionais como uso da vitamina D e seus metabólitos que participam na regulação da homeostase de cálcio e fósforo por um mecanismo que aumenta a captação intestinal destes, diminuindo as perdas renais e estimulando a reabsorção óssea. O presente estudo teve como objetivo utilizar a Solanum glaucophyllum como fonte suplementar de 1,25-dihidroxicolecalciferol nas características ósseas de frangos de corte. Para tal, foram desenvolvidos dois ensaios. No ensaio 1 utilizando frango de corte fêmea e no 2 frango de corte macho. Avaliou-se a utilização suplementar de Solanum glaucophyllum como fonte de vitamina D3 ativa. Foram utilizados um total de 1.296 frangos de corte da marca comercial Cobb® em delineamento em blocos ao acaso com 6 tratamentos e 6 repetições com 18 aves por unidade experimental. Os tratamentos consistiram na suplementação de 0,0; 0,5; 1,0; 1,5; 2,0 e 2,5 μg de vitamina D3 ativa/kg de ração. Aos 21 e 35 dias de idade as aves foram pesadas e um frango por repetição com peso médio do lote foi abatido para se obter os tibiotarsos. As variáveis analisadas foram os pesos in natura, seco e desengordurado, comprimento, diâmetros, resistência óssea, índice Seedor, teores de proteínas colagenosas e não colagenosas, minerais e cinzas. No ensaio 1, aos 35 dias de idade, a composição orgânica e mineral dos ossos (peso in natura, proteínas não colagenosas, cinzas) foi afetada pelo fornecimento suplementar de 2,5 μg de vitamina D3 na forma de 1,25(OH)2D3. Já no ensaio 2 as características ósseas foram afetadas pela suplementação de vitamina D3 ativa nas rações. Recomenda-se até 1,5 μg de vitamina D3 ativa nas rações para frangos de corte machos de 8 a 35 dias de idade. / Poultry farming has always aimed to maximize production efficiency in broilers, but unwanted characteristics came together with these improvements. Bone disorders are caused by rapid deposition of animal tissue, while the bone development continues its normal growth. This meant the movement capacity was damaged, as the welfare and consequently the development of these birds. Several nutritional programs have been emerged, such as the use of vitamin D and its metabolites involved in regulating calcium and phosphorous homeostasis by a mechanism which enhances their intestinal uptake, reducing renal losses and stimulating bone resorption. With the present study, it was aimed to use Solanum glaucophyllum as a supplementary source of 1,25-dihydroxycholecalciferol in bone characteristics of broiler chickens. To this end, two assays were conducted. In the assay 1, they were used female broilers, and in the assay 2, male broilers. It was evaluated the additional use of Solanum glaucophyllum as a source of active vitamin D3. A total of 1,296 broiler chickens of Cobb® trademark were used in a randomized block design, with 6 treatments and 6 repetitions with 18 birds. The treatments consisted of supplementation of 0.0; 0.5; 1.0; 1.5; 2.0 and 2.5 μg of active vitamin D3 / kg of feed. At 21 and 35 days of age, the birds were weighed and one chicken by repetition, representing the average weight of the lot, was slaughtered in order to get the tibia tarsus. The analyzed variables included fresh, dry and degreased weights, length, diameter, bone resistance, Seedor index, collagenous and non-collagenous protein contents, minerals and ashes. In the assay 1, at 35 days of age , the organic and mineral composition of the bones ( fresh weight, non- collagenous proteins and ashes) were affected by the additional provision of 2.5 μg of vitamin D3 in the 1,25 (OH ) 2D3 form. In the assay 2, bone characteristics were affected by active vitamin D3 supplementation in the diet. It is recommended the provision of 1.5 μg of active vitamin D3 in feed for broilers from 8 to 35 days old.
29

Encapsulação de colecalciferol (vitamina D3) por spray chilling / Encapsulation cholecalciferol (vitamin D3) by spray chilling

Orfa Collazos Paucar 26 February 2016 (has links)
A indústria de alimentos está constantemente desenvolvendo produtos que fornecem, além de nutrientes, benefícios adicionais à saúde, tais como os enriquecidos com vitaminas. A vitamina D3 (colecalciferol) é sintetizada na pele durante a exposição da luz solar, controla a homeostase de cálcio e fósforo, metabolismo ósseo, pressão arterial e reabsorção renal de cálcio. O processo de microencapsulação vem sendo bastante aplicado em alimentos e um dos objetivos principais é o controle da liberação do agente ativo no momento e local desejado. A tecnologia de spray chilling é interessante para a microencapsulação de vitaminas lipossolúveis. O objetivo deste trabalho foi microencapsular vitamina D3, utilizando o método de spray chilling para a produção das micropartículas lipídicas sólidas (MLS). Para produção das MLS utilizou-se gordura vegetal com ponto de fusão em torno de 48 °C como carreador. Três tratamentos foram estabelecidos: sem aditivos (T1), com adição de 1% de cera de abelha (T2) e com 1% de lecitina de soja (T3). As micropartículas foram caracterizadas quanto à morfologia por microscopia eletrônica de varredura, tamanho médio por difração a laser, espectroscopia no infravermelho por transformada de Fourier (FTIR) e foi analisada a estabilidade da vitamina D3 durante o armazenamento a 10 e 25 °C, por meio de quantificações periódicas em cromatografia líquida de alta eficiência (CLAE). As micropartículas obtidas foram esféricas, semelhantes morfologicamente e com distribuição monocaudal de partículas. O tamanho médio das partículas variou em função dos seus ingredientes, sendo que as micropartículas produzidas apenas com vitamina e gordura foram menores em relação às demais (83,0% < 100 &micro;m). A espectroscopia na região do infravermelho (FTIR) demonstrou que não ocorreu interação entre os ingredientes. A estabilidade da vitamina D3 encapsulada foi satisfatória ao longo de 65 dias com valores superiores a 87% para os três tratamentos e a temperatura apresentou influência na estabilidade. As MLS produzidas com cera apresentaram melhores resultados de estabilidade de vitamina D3 com valores de 90,18 ± 2,23 % após 65 dias de estocagem. Esses resultados são promissores e demostram a viabilidade da técnica de spray chilling na produção de MLS carregadas de vitamina D3, possibilitando uma futura aplicação em alimentos. / The food industry is constantly developing products that provide, in addition to nutrients, additional health benefits such as enriched food with vitamins. Vitamin D3 (cholecalciferol), which is synthesized in the skin during exposure of sunlight, controls the homeostasis of calcium and phosphorus, bone metabolism, blood pressure and renal reabsorption of calcium. The microencapsulation process has been widely applied in food and is a key objective to control the release of active agents at specific time and desired location. The spray chilling technology is interesting for microencapsulation of fat-soluble vitamins. The objective of this work was microencapsulating vitamin D3 using the spray chilling method for the production of solid lipid microparticles (SLM). For the production of the SLM it was used vegetable fat with melting point around at 48 °C as a carrier. Three treatments were established: no additives (T1), 1% of beeswax (T2), and 1% soybean lecithin (T3). The morphology of microparticles was characterized by scanning electron microscopy, laser diffraction (average size) and Fourier transform infrared spectroscopy (FTIR). Additionally, vitamin D3 stability was examined during storage at 10 and 25 °C, through periodic measurements by High-performance liquid chromatography (HLPC). The microparticles obtained were spherical with similar morphology and unimodal size distribution. The average particle size varied according to composition wherein microparticles produced with vitamin and fat were lower than other (83.0% of particles smaller than 100 &micro;m). Spectroscopy in the infrared (FTIR) showed that there was no interaction between the components. The stability of vitamin D3 encapsulated was satisfactory over 65 days with values greater than 87% for the three treatments and temperature have any influence on the stability. The SLM produced with wax showed better stability for vitamin D3 with values of 90.18 ± 2.23% after 65 days of storage. These results are promising and demonstrate the feasibility of spray chilling technique in the production of SLM loaded with vitamin D3, allowing future application in foods.
30

Financování s využitím PPP projektů (se zaměřením na dopravní infrastrukturu) / Financing with the PPP projects ( focused on transport infrastructure)

Malaníková, Alexandra January 2009 (has links)
The diploma thesis is describing Private Public Partnership (PPP) and its characterization. Another part is about foreign experience with PPP projects and about implementation these projects on the czech market. The whole thesis is focused on transport infrastructure and the practical part analyses the building of highway D3 in the south part of the Czech republic.

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