Expectativas y volatilidad condicionada: los tipos de interés en el mercado interbancario

En este trabajo examinamos si la teoría de expectativas con primas de liquidez constantes puede explicar la estructura temporal de los tipos de interés de pequeños vencimientos en el mercado interbancario de depósitos español, para datos mensuales desde 1977 hasta 1995. Utilizamos el contraste de Campbell y Shiller (1987) basado en un modelo VAR cointegrado. A partir de las estimaciones consistentes de dicho modelo obtenemos la magnitud y persistencia de los shocks a través de la simulación de la respuesta al impulso, y estimaciones eficientes de los parámetros modelizando la varianza condicional que es variable en el tiempo. En este sentido, se proponen varios esquemas de volatilidad que permiten plantear distintas aproximaciones de laincertidumbre en un entorno multiecuacional GARCH y que están basadas en el modelo de expectativas propuesto. La evidencia empírica muestra que se incumple la teoría de las expectativas, que existe una dinámica conjunta a corto plazo para los tipos de interés y el diferencial que está definida por un modelo VAR(4)-GARCH( 1,1)-BEKK (que está próximo a la integrabilidad en varianza), y que existen distintos factores de riesgo que afectan a las primas en los plazos estudiados

Omistajuus oppilasomisteisessa työsuuskunnassa, Case Palveluosuuskunta +Hymy

Tässä tutkielmassa tarkasteltiin omistajuuden muodostumista työosuuskunnassa. Tutkielman tavoitteena oli ymmärtää työosuuskuntien omistajuutta sekä niitä tavoitteita, joita omistajuuteen liittyy. Tutkielma on laadullinen tutkimus, jonka tutkimusmenetelmänä on käytetty teemahaastattelua. Tutkimusaineisto kerättiin tekemällä kuusi haastattelua, jotka tallennettiin ja litteroitiin sanasta sanaan. Tutkielman perusteella voitiin näyttää, että omistajuus koostuu niin taloudellisrationaalisista kuin psykologisista elementeistä. Kollektiiviset omistajuuden tekijät nousivat individualistisia tekijöitä merkittävämmiksi.

Os produtos naturais e a química medicinal moderna

Natural products have been utilized by humans since ancient times and the relief and cure of their diseases was the first purpose for using natural products in medicine. The history of the oriental and occidental civilizations is very rich in examples of the utilization of natural products in medicine and health care. Chinese traditional medicine is one of the most important examples of how natural products can be efficient in the treatment of diseases, and it points to the importance of scientific research on natural products, concerning the discovery of new active chemical entities. The complexity, chemical diversity and biological properties of natural products always fascinated people, and during the last 200 years, this led to the discovery of important new drugs. In the last 30 years, the development of new bioassay techniques, biotechnology methods, bio-guided phytochemical studies, automated high throughput screening and high performance analytical methods, have introduced new concepts and possibilities of rational drug design and drug discovery. In this context, natural products have played an important and decisive role in the development of modern medicinal chemistry.

Biodiversidade flavonoídica e aspectos farmacológicos em espécies dos gêneros Ouratea e Luxemburgia (Ochnaceae)

This work describes the flavonoids and biflavonoids found in species of Ouratea and Luxemburgia as chemical markers that serve to detect the difference between these taxa according to the linkage between the flavonoidal units. A rational nomenclature is proposed and the pharmacological potencial is discussed.

Projecte executiu d'una instal·lació de climatització i control d'un habitatge unifamiliar

Moltes vegades l’usuari d’una instal•lació de climatització o calefacció, no dóna la suficient importància al sistema que l’hi ha de proporcionar un millor confort amb el màxim rendiment. Aquest confort és un factor determinant, entre molts d’altres, de la “qualitat de vida”. Mentre que el rendiment és un factor important a nivell econòmic i ecològic. Tot i tenir prevalença els aspectes d’estalvi energètic, aquests no impliquen haver de renunciar a un confort tèrmic i a un estalvi econòmic. Un dels aspectes que es centra el projecte és promoure l’ús racional de les fonts energètiques (solar, biomassa) per a la correcta climatització dels habitatges. El projecte es desenvolupa en l’àmbit domèstic, concretament correspon a un habitatge unifamiliar. Aquest està situat a la població de Roda de Ter, província de Barcelona. L’objectiu principal del projecte és l’elecció del sistema de climatització i el seu dimensionament, per tal de donar el màxim confort als usuaris que habitin a la vivenda. Criteris ambientals i eficients han estat objecte a considerar pel disseny constructiu de l’habitatge. Una de les mesures importants presses en el projecte, ha estat l’elecció de les diferents parts que formen la instal•lació de climatització. Es fa referència als aïllaments dels tancaments, el sistema solar de recolzament, equips de producció de fred i calor, entre d’altres. En el projecte, s’ha dut a terme un estudi dels diferents tancaments de l’habitatge, tot determinat per a cada un d’ells, el seu coeficient de transmissió tèrmica. Per seleccionar l’equipament més adequat s’ha partit de les condicions climatològiques del municipi de Roda de Ter i s’ha realitzat el càlcul de les necessitats tèrmiques de l’edifici. L’habitatge incorpora una instal•lació de captació solar tèrmica. Aquesta aportarà un suport energètic a tot el sistema de producció de calor, ja sigui per la producció d’aigua calenta sanitària com per el calefactat de la vivenda. La col•locació dels panells a la façana sud tindrà una doble funció: a més de proporcionar energia solar tèrmica, serviran d’elements de protecció solar en la temporada d’estiu. La caldera usada per donar recolzament tèrmic utilitzarà com a combustible el “pellet”. El “pellet” és un tipus de biomassa llenyosa que consta d’un derivat de la fusta en format granulat. Es defineix i es detalla el consum energètic en biomassa, electricitat i cost econòmic anual que ocasionarà la instal.lació dissenyada. El sistema de terra radiant adoptat permetrà el refrescament en èpoques estivals i el calefactat en èpoques hivernals. Aquest donarà el confort tèrmic necessari a cada estança de l’habitatge. En el projecte també es marquen les pautes bàsiques pel control de la instal•lació solar així com el control dels grups de bombament i la mescla d’aigua del terra radiant.

Seqüenciamento de peptídeos usando espectrometria de massas: um guia prático

This paper introduces the basics of peptide mass spectra interpretation applied to proteomics and is directed to chemists, biochemists and biologists. The manuscript presents a well detailed protocol aiming to serve as a first choice guide for understanding peptide sequencing. The tutorial was elaborated based on both a thorough bibliographic revision and the author's experience. In order to prove the applicability of the proposed guide, spectra obtained on different instruments have been successfully interpreted by applying the presented rational.

O ensino da química na Escola Superior de Agricultura "São Bento", Olinda - São Lourenço da Mata - Pernambuco (1912-1936)

The present work proposes the investigation of the role of chemistry in the curriculum of the Higher School of Agriculture "São Bento" (1912-1936) and its function in the education of agronomic engineers. The circumstances under which the Higher Schools of Agriculture and Veterinary Medicine in Olinda were founded at the beginning of the XXth century are discussed. The article further treats the influence of the principles of Justus von Liebig, which were seen at that time as essential for a rational agriculture.

Characterizing Propionibacterium freudenreichii ssp. shermanii JS and Lactobacillus rhamnosus LC705 as a new probiotic combination: basic properties of JS and pilot in vivo assessment of the combination

Characterizing Propionibacterium freudenreichii ssp. shermanii JS and Lactobacillus rhamnosus LC705 as a new probiotic combination: basic properties of JS and pilot in vivo assessment of the combination Each candidate probiotic strain has to have the documentation for the proper identification with current molecular tools, for the biological properties, for the safety aspects and for the health benefits in human trials if the intention is to apply the strain as health promoting culture in the commercial applications. No generalization based on species properties of an existing probiotic are valid for any novel strain, as strain specific differences appear e.g. in the resistance to GI tract conditions and in health promoting benefits (Madsen, 2006). The strain evaluation based on individual strain specific probiotic characteristics is therefore the first key action for the selection of the new probiotic candidate. The ultimate goal in the selection of the probiotic strain is to provide adequate amounts of active, living cells for the application and to guarantee that the cells are physiologically strong enough to survive and be biologically active in the adverse environmental conditions in the product and in GI tract of the host. The in vivo intervention studies are expensive and time consuming; therefore it is not rational to test all the possible candidates in vivo. Thus, the proper in vitro studies are helping to eliminate strains which are unlikely to perform well in vivo. The aims of this study were to characterize the strains of Propionibacterium freudenreichii ssp. shermanii JS and Lactobacillus rhamnosus LC705, both used for decades as cheese starter cultures, for their technological and possible probiotic functionality applied in a combined culture. The in vitro studies of Propionibacterium freudenreichii ssp. shermanii JS focused on the monitoring of the viability rates during the acid and bile treatments and on the safety aspects such as antibiotic susceptibility and adhesion. The studies with the combination of the strains JS and LC705 administered in fruit juices monitored the survival of the strains JS and LC705 during the GI transit and their effect on gut wellbeing properties measured as relief of constipation. In addition, safety parameters such as side effects and some peripheral immune parameters were assessed. Separately, the combination of P. freudenreichii ssp. shermanii JS and Lactobacillus rhamnosus LC705 was evaluated from the technological point of view as a bioprotective culture in fermented foods and wheat bread applications. In this study, the role ofP. freudenreichii ssp. shermanii JS as a candidate probiotic culture alone and in a combination with L. rhamnosus LC705 was demonstrated. Both strains were transiently recovered in high numbers in fecal samples of healthy adults during the consumption period. The good survival through the GI transit was proven for both strains with a recovery rate from 70 to 80% for the JS strain and from 40 to 60% for the LC705 strain from the daily dose of 10 log10 CFU. The good survival was shown from the consumption of fruit juices which do not provide similar matrix protection for the cells as milk based products. The strain JS did not pose

Pienen perheyrityksen johtoryhmä yrittäjänä

Tämän tutkimuksen tavoitteena on selvittää miten yrittäjyys näkyy pienen perheyrityksen johtoryhmän toiminnassa. Pyrkimyksenä on ymmärtää millaisia nämä johtoryhmät ovat. Tutkimuksessa pyritään myös selvittämään, miten nämä tiimit toimivat. Lopuksi tutkimuksen kiinnostuksen kohteena on, mitä suoritteita tiimit saavat aikaan. Tutkimuksessa on käytetty kvalitatiivista tutkimusmenetelmää. Tutkimus on toteutettu teemahaastatteluina valituissa pienissä perheyrityksissä. Tutkimustulokset osoittavat, että pienissä perheyrityksissä toimivat johtoryhmät ovat hyvin erilaisia koostumukseltaan. Usein niissä on samoja henkilöitä kuin hallituksessa. Heterogeeniset tiimit osoittautuivat kuitenkin toimivimmiksi. Pienissä perheyrityksissä todettiin olevan sekä johtoryhmiä että yrittäjämäisiä tiimejä. Johtoryhmä voi tuoda yritykseen uusia johtamiskäytäntöjä ja siten järkevöittää yrityksen johtamista ja kehittymistä.

A química supramolecular de complexos pirazólicos

The purpose of this review is to describe the progress in the supramolecular chemistry of the pyrazolyl-based metal complexes. The text is written under the structural point of view, emphasizing the role of the covalent and non-covalent interactions in the rational construction of super and supramolecules.

Caracterización de la reactividad intrínseca de los halobencenos en el modelo conceptual de la teoría de funcionales de la densidad (TFD)

The aim of this paper is to study the family of halobenzenes for characterizing their intrinsic reactivity and in this way to establish a rational order of the intrinsic reactivity of this family of molecules in the electrophilic aromatic substitution. This study was carried out in the framework of Density Functional Theory which provides a global and local index that can be used in the characterization of the reactivity. This index is related to some concept derivatives of experimental chemistry, being a good approach to the characterization of halobenzenes.

O papel governamental como ator essencial para a P&D de medicamentos: um estudo de casos

The importance of natural products as a source of new high value-added drugs has, no doubt, transformed Brazilian megadiversity into one of the country's most valuable and strategic assets. Thus the rational exploration of the Brazilian flora on an economic basis should be considered as part of a national development strategy. In this respect, governmental mechanisms to stimulate regulation on the access, bioprospection and industrial use of natural products represent a crucial issue. The aim of this paper is to show how the incentives and institutional arrangements that led to one of the greatest breakthroughs in the pharmaceutical industry, the development and commercialization of the anti-cancer agent Taxol, could be applied to the Brazilian case.

Imobilização de enzimas em suportes cromatográficos: uma ferramenta na busca por substâncias bioativas

The development and characterization of bioreactors or IMER (immobilized enzyme reactors) as research tools are important in the scope of medicinal chemistry and constitute an alternative for the rational development of drugs. This approach does not require highly purified enzymes or a great amount of protein, but increase the enzymatic stability against heat, organic solvents and pH, without too much loss of catalyst activity. Immobilized enzyme reactors (IMER) can be used for the accomplishment of high efficiency screening on-line and, thus inhibitors can be quickly identified. Here, we emphasize the development of IMER by use of different methods of immobilization and chromatographic supports. Their applications, in different areas of research, are also fully discussed.

Contribuição da fitoquímica para o desenvolvimento de um país emergente

The sustainable development of an emergent country is dependent on a consistent scientific, technologic and innovative policy, on nature and biodiversity, on a rational exploration of natural resources to feeding, social advance and economical aim along with maintenance of health and diseases treatment. Phytochemical investigations may be used to contribute with development throughout undergraduate and graduate career preparing professionals with qualification to these activities, as researcher and professor, including discovering and divulgation of new scientific knowlegments. The role of organic compounds produced by secondary metabolism of plants in the development of new drugs is presented (e. g.) throughout exposition using examples of features involved in this activity, since the recognition of a plant-derived popular medicine, until the laboratory semi-synthesis of its main constituents. Several aspects related to the use of some vegetable species in treatment of many tropical diseases are pointed. Economical and social importance of isolation, structural characterization, pharmacological investigation and chemical transformations of new natural organic substances isolated from the plants are related.

Proteases de Leishmania: novos alvos para o desenvolvimento racional de fármacos

Leishmania causes tegumental and visceral diseases called leishmaniasis. Disease control is possible interrupting the transmission cycle, but HIV co-infection, chemotheraphy toxicity and lack of a vaccine are paramount difficulties. So, is necessary to study new Leishmania molecules and investigate the possibility to develop rational drugs using these molecules as targets. Leishmania express many peptidases during their life, and cysteine are the most abundant protease and many inhibitors were developed but failed to kill parasites. On the other hand, inhibitors of serine proteases killed promastigotes, indicating the possibility of these enzymes to be important targets in the development of anti-Leishmania drugs.