Credit risk & forward price models

Doutoramento em Gestão

Digestibility of different wheat products in white shrimp Litopenaeus vannamei juveniles

Dry matter, energy, crude protein and amino acid apparent digestibility coefficients (ADCs) were determined in white shrimp juveniles for six wheat products: hard red winter whole grain meal (HWG), Rayon whole grain meal (RWG), Durum whole grain meal (DWG), hard red winter clear flour (HCF), mixed wheat 2nd clear flour (MCF) and semolina (S). The test diets included 30% of the test ingredients and 70% of a ground commercial diet supplemented with 1% chromic oxide and 1% sodium alginate. Amino acid contents in the ingredients, diets and feces were analyzed, and digestibility was determined by difference in order to minimize the impact of endogenous amino acid losses; crude protein and amino acids ADCswere adjusted for dietary preprandial losses in seawater. In general, nutrients digestibility was far higher in the wheat products than in the fish meal-based reference diet. Drymatter and crude proteinADCswere not statistically different amongwheat products (from84 to 96% and from88 to 107% respectively). Energy ADCs were significantly higher for clear flours (96% for HCF and MCF) than forwhole grainmeals and S (from83 to 86%). Total amino acids (TAA) and essentialamino acids (EAA) ADCs, once adjusted for preprandial leaching fromthe experimental diets, ranged from81 to 89% and from 58 to 81% respectively, and were statistically comparable among wheat products. Low Thr ADCs appear as a common feature of the amino acids digestibility profiles for whole grain meals, clear flours, or semolina.

Incorporation of dietary nitrogen from fish meal and pea meal ( Pisum sativum ) in muscle tissue of Pacific white shrimp ( Litopenaeus vannamei ) fed low protein compound diets

Stable isotope analyses were applied to explore the relative dietary nitrogen contributions from fish meal and pea meal (Pisum sativum) to muscle tissue of Pacific white shrimp postlarvae (141 ± 31 mg) fed low protein diets having different proportions of both ingredients as the sole dietary protein sources. A negative control diet was formulated to contain 100% pea meal and six more isoproteic diets to have decreasing levels of pea meal-derived nitrogen: 95%, 85%, 70%, 55%, 40% and 0% of the initial level. Growth rates were negatively correlated to dietary pea protein inclusion due to progressive essential amino acid deficiencies (sulphur amino acids, threonine, lysine, histidine). The nitrogen turnover rate significantly increased in muscle tissue of shrimps fed diets having high levels of pea meal; however, contrary to observations from a previous study using soy protein, the relative contributions of dietary nitrogen from pea meal to shrimp muscle tissue were equal or higher than expected contributions established by the dietary formulations. Results highlight the effectiveness of stable isotope analysis in assessing the nutritional contributions of alternative ingredients for aquaculture feeds and the potential suitability of pea as a source of protein (provided the diets are nutritionally balanced)

Simultaneous estimation of the nutritional contribution of fish meal, soy protein isolate and corn gluten to the growth of Pacific white shrimp (Litopenaeus vannamei) using dual stable isotope analysis

The nutritional contribution of the dietary nitrogen, carbon and total dry matter supplied by fish meal (FM), soy protein isolate (SP) and corn gluten (CG) to the growth of Pacific white shrimp Litopenaeus vannamei was assessed by means of isotopic analyses. As SP and CG are ingredients derived from plants having different photosynthetic pathways which imprint specific carbon isotope values to plant tissues, their isotopic values were contrasting. FM is isotopically different to these plant meals with regards to both, carbon and nitrogen. Such natural isotopic differences were used to design experimental diets having contrasting isotopic signatures. Seven isoproteic (36% crude protein), isoenergetic (4.7 kcal g−1) diets were formulated; three diets consisted in isotopic controls manufactured with only one main ingredient supplying dietary nitrogen and carbon: 100% FM (diet 100F), 100% SP (diet 100S) and 100% CG (diet 100G). Four more diets were formulated with varying mixtures of these three ingredients, one included 33% of each ingredient on a dietary nitrogen basis (diet 33FSG) and the other three included a proportion 50:25:25 for each of the three ingredients (diets 50FSG, 50SGF and 50GFS). At the end of the bioassay there were no significant differences in growth rate in shrimps fed on the four mixed diets and diet 100F (k=0.215–0.224). Growth rates were significantly lower (k=0.163–0.201) in shrimps grown on diets containing only plant meals. Carbon and nitrogen stable isotope values (δ13C and δ15N) were measured in experimental diets and shrimp muscle tissue and results were incorporated into a three-source, two-isotope mixing model. The relative contributions of dietary nitrogen, carbon and total dry matter from FM, SP and CG to growth were statistically similar to the proportions established in most of the diets after correcting for the apparent digestibility coefficients of the ingredients. Dietary nitrogen available in diet 33FSG was incorporated in muscle tissue at proportions representing 24, 35 and 41% of the respective ingredients. Diet 50GSF contributed significantly higher amounts of dietary nitrogen from CG than from FM. When the level of dietary nitrogen derived from FM was increased in diet 50FSG, nutrient contributions were more comparable to the available dietary proportions as there was an incorporation of 44, 29 and 27% from FM, SP and CG, respectively. Nutritional contributions from SP were very consistent to the dietary proportions established in the experimental diets.

Apparent digestibility of dry matter, crude protein, and amino acids of six rendered by-products in juvenile Litopenaeus vannamei

Apparent digestibility coefficients (ADC) of dry matter, crude protein (CP), and amino acids (AA) were evaluated in diets with six rendered by-products used to feed juvenile Pacific white shrimp: two poultry meals (poultry meal 1, 69% CP; poultry meal 2, 72% CP), two feather meals (89% CP), one blood meal (96% CP), and one pork meal (57% CP). Experimental diets were formulated with 30% of the test ingredient and 70% of a commercial diet supplemented with 1% of chromium oxide as inert marker. AA contents in ingredients, diets, leached diets, and feces were determined by high performance liquid chromatography. Preprandial AA losses attributed to leaching were higher in the blood meal diet (15%) and pork meal diet (10%). Poultry meal diets 1 and 2 showed mean AA losses of 3% and 5%, respectively, while the reference diet had a mean AA leaching of 6%. The AA that had the highest leaching rates were lysine (21%), methionine (15%), and histidine (12%). The ADC of dry matter was higher for poultry meals 1 (70%) and 2 (73%), followed by pork meal (69%), feather meals (61%), and blood meal (57%). The digestibility of CP was higher for poultry meals (78–80%), followed by pork meal (76%), and blood meal and feather meals (65–67%). The digestibility of CP in the reference diet (83%) was higher than that observed for all the animal by-product meals except the poultry meals. The ADC of the sum of AA adjusted for nutrient leaching fluctuated from 65% for blood meal to 80% for poultry meals.

Aplicações biotecnológicas do supressor de silenciamento de cucumber mosaic virus

Tese de Doutoramento, Ciências Agrárias, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015

Projectar com luz, cor e matéria

Dissertação para obtenção do grau de Mestre em Arquitectura com Especialização em Arquitectura de Interiores, apresentada na Universidade de Lisboa - Faculdade de Arquitectura.

Saúde e remédios caseiros

Inserido no âmbito do Projeto Europeu “My Food My Medicine” (Meu Alimento Meu Medicamento), que tem como ideia base o conselho de Hipócrates de que a nossa alimentação deve ser o nosso medicamento, realizou-se um Trabalho de Projeto de formação sobre a manutenção da saúde através da promoção de uma alimentação saudável e pela recuperação do uso de receitas tradicionais/caseiras de medicamentos naturais usados ancestralmente na resposta aos distúrbios de saúde mais comuns. Objetivos Gerais: O principal objetivo do projeto é levar os participantes a compreender os princípios e receitas da medicina tradicional e natural, as características dos ingredientes e os seus benefícios para a saúde. Metodologia: Elaboração de um projeto de formação com materiais educativos, testados pela sua aplicação, e realização de questionários a formadores e formandos. Resultados: Verificou-se algum conhecimento por parte dos formandos de grande parte das receitas de remédios caseiros, embora por vezes com alguma desconfiança da sua eficácia, acreditamos terem ficado com intenção de usar a maior parte das receitas expostas pela sua facilidade de elaboração e pela valorização crescente da tradicionalidade e ancestralidade, julgamos desta forma poder ter contribuído para a promoção e manutenção da saúde; Abstract: As part of the European Project "My Food My Medicine” which has as its central idea the Board of Hippocrates that our food should be our medicine i.e., a healthy diet is the foundation of a healthy life, this report presents an educational project about the maintenance of health through the promotion of healthy eating that is reflected also by the use of natural medicines based on homemade/traditional recipes used ancestrally that respond to the most common health disorders. Objectives: Take the participants to understand the basic principles and the recipes of traditional medicine, the characteristics of the ingredients and their health benefits. Methodology: Development of an educational project and educational materials, tested trough out its implementation, and conducting questionnaires to trainers and trainees. Results: The objective was accomplished. It was found some familiarity on the part of the graduates of most recipes for home remedies although sometimes with some distrust of their validity. The schooling contributed to health promotion. The trainees demonstrated the intention to use the recipes exposed as a way to maintain a healthy life.

Saccharomyces cerevisiae as a toxicological model to study synthetic cannabinoids and its pyrolysis products

Poster presented at the 7th European Academy of Forensic Science Conference. Prague, 6-11 September 2015

A RBES for Generating Automatically Personalized Menus

Food bought at supermarkets in, for instance, North America or the European Union, give comprehensive information about ingredients and allergens. Meanwhile, the menus of restaurants are usually incomplete and cannot be normally completed by the waiter. This is specially important when traveling to countries with a di erent culture. A curious example is "calamares en su tinta" (squid in its own ink), a common dish in Spain. Its brief description would be "squid with boiled rice in its own (black) ink", but an ingredient of its sauce is flour, a fact very important for celiacs. There are constraints based on religious believes, due to food allergies or to illnesses, while others just derive from personal preferences. Another complicated situation arise in hospitals, where the doctors' nutritional recommendations have to be added to the patient's usual constraints. We have therefore designed and developed a Rule Based Expert System (RBES) that can address these problems. The rules derive directly from the recipes of the di fferent dishes and contain the information about the required ingredients and ways of cooking. In fact, we distinguish: ingredients and ways of cooking, intermediate products (like sauces, that aren't always made explicit) and final products (the dishes listed in the menu of the restaurant). For a certain restaurant, customer and instant, the input to the RBES are: actualized stock of ingredients and personal characteristics of that customer. The RBES then prepares a "personalized menu" using set operations and knowledge extraction (thanks to an algebraic inference engine [1]). The RBES has been implemented in the computer algebra system MapleTM2015. A rst version of this work was presented at "Applications of Computer Algebra 2015" (ACA'2015) conference. The corresponding abstract is available at [2].

Extraction and characterization of Raphanus Sativus seed oil obtained by different methods

Purpose: To evaluate the impact of three different extraction methods on yield, physicochemical properties and bioactive ingredients of Raphanus sativus seed oil. Methods: Raphanus Sativus seed oil was prepared by traditional solvent extraction (SE), super-critical carbon dioxide extraction (SCE) and sub-critical propane extraction (SPE). The yield, physicochemical properties, fatty acid composition and oxidative stability of the oil extracts were compared. The contents of tocopherol and sulforaphene in the oils were also determined. Results: The oil yield obtained by SPE, SE and SCE were 33.69, 27.17 and 24.10 %, respectively. There were no significant differences in physicochemical properties and fatty acid compositions of oils extracted by the three methods. However, SCE oil had the best oxidative stability, and highest contents of vitamin E and sulforaphene, followed by oils from SPE and SE. Conclusion: SCE is highly selective for tocopherol and sulforaphene, which could explain its high oil oxidative stability. These results suggest that of the three extraction methods, SCE is best suited for preparing medicinal radish seed oil.

Quality evaluation of cortex berberidis from different geographical origins by simultaneous high performance liquid chromatography combined with statistical methods

Purpose: To develop an effective method for evaluating the quality of Cortex berberidis from different geographical origins. Methods: A simple, precise and accurate high performance liquid chromatography (HPLC) method was first developed for simultaneous quantification of four active alkaloids (magnoflorine, jatrorrhizine, palmatine, and berberine) in Cortex berberidis obtained from Qinghai, Tibet and Sichuan Provinces of China. Method validation was performed in terms of precision, repeatability, stability, accuracy, and linearity. Besides, partial least squares discriminant analysis (PLS-DA) and one-way analysis of variance (ANOVA) were applied to study the quality variations of Cortex berberidis from various geographical origins. Results: The proposed HPLC method showed good linearity, precision, repeatability, and accuracy. The four alkaloids were detected in all samples of Cortex berberidis. Among them, magnoflorine (36.46 - 87.30 mg/g) consistently showed the highest amounts in all the samples, followed by berberine (16.00 - 37.50 mg/g). The content varied in the range of 0.66 - 4.57 mg/g for palmatine and 1.53 - 16.26 mg/g for jatrorrhizine, respectively. The total content of the four alkaloids ranged from 67.62 to 114.79 mg/g. Moreover, the results obtained by the PLS-DA and ANOVA showed that magnoflorine level and the total content of these four alkaloids in Qinghai and Tibet samples were significantly higher (p < 0.01) than those in Sichuan samples. Conclusion: Quantification of multi-ingredients by HPLC combined with statistical methods provide an effective approach for achieving origin discrimination and quality evaluation of Cortex berberidis. The quality of Cortex berberidis closely correlates to the geographical origin of the samples, with Cortex berberidis samples from Qinghai and Tibet exhibiting superior qualities to those from Sichuan.

Digestibilidade Aparente de Ingredientes pela Tilápia do Nilo (Oreochromis niloticus)

Avaliou-se a digestibilidade aparente do milho, amido de milho, milho extrusado, germe de milho, sorgo, farelo de trigo, farelo de arroz, glúten 21, glúten 60, farelo de soja, farelo de canola, farelo de algodão, farinha de peixe, farinha de carne, farinha de vísceras de aves, farinha de sangue e farinha de penas. Confeccionaram-se 18 rações, marcadas com 0,10% de óxido de crômio III, uma delas, basal purificada, e as demais, contendo os ingredientes. Os peixes, 100 juvenis com 100±10 g, foram alojados em cinco tanques-rede para facilitar o manejo de alimentação e a coleta de fezes e permaneceram, durante o dia, em cinco aquários (250 L) de alimentação, recebendo refeições à vontade das 8 às 17h30. Após, foram transferidos para cinco aquários (300 L) de coleta de fezes, onde permaneceram até a manhã do dia subseqüente. O coeficiente de digestibilidade aparente dos ingredientes foi calculado com base no teor de óxido crômio da ração e das fezes. Com base nos resultados, concluiu-se que, entre os ingredientes energéticos, o milho apresentou o melhor coeficiente de digestibilidade aparente, seguindo-se o milho extrusado, o farelo de trigo e o farelo de arroz; dos ingredientes protéicos - vegetal, o glúten 60 e o glúten 21, seguidos do farelo de canola, apresentou os melhores coeficientes e dos protéicos - animal, destacou-se a farinha de vísceras de aves, seguida da farinha de peixes, enquanto os piores coeficientes foram proporcionados pela farinha de penas e farinha de sangue.

Desempenho zootécnico de girinos de rã-touro com diferentes níveis de proteína e energia digestíveis

A partir dos valores de digestibilidade de alguns ingredientes foram propostas dietas, com diferentes níveis de proteína e energia digestíveis, em esquema fatorial 3 x 3, destinadas a girinos de rã-touro para avaliar o desempenho zootécnico. O experimento, com duração de 60 dias, foi conduzido com 810 girinos, oriundos da mesma desova, distribuídos em 27 caixas de polipropileno, em uma densidade de 1girino/L. O delineamento experimental foi um esquema fatorial com três níveis de proteína digestível (27; 31 e 35%) e três níveis de energia digestível (2.700; 2.800 e 2.900kcal/kg) com três réplicas. Os parâmetros avaliados aos 60 dias foram ganho de peso, consumo da dieta, consumo em proteína da dieta, conversão alimentar, taxa de eficiência proteica e índice de sobrevivência. Os resultados foram submetidos à análise de variância e ao teste de Duncan (95% de precisão). Os resultados encontrados não apresentaram interação entre proteína e energia digestível para nenhum parâmetro avaliado. em relação à proteína digestível, foram verificadas diferenças nos parâmetros consumo em proteína da dieta e taxa de eficiência proteica (TEP), o que demonstra ineficiência das dietas com altos valores proteicos. Deve-se oferecer aos girinos de rã-touro dietas com 27% de proteína digestível, por apresentarem melhor resultado para taxa de eficiência proteica e para consumo em proteína da dieta.

Avaliação ecotoxicológica de fármacos psicotrópicos e suas possíveis interações com nanomateriais usando embriões de peixe-zebra

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Animal, 2016.