941 resultados para DIVERSIFICATION
Resumo:
Tämän tutkimuksen tavoitteena oli analysoida strategisen johtamisen omistajalähtöistä johtamismallia kirjallisuuden valossa. Tutkimusmenetelmänä käytettiin olemassa olevaan tekstiaineistoon perustuvaa tulkitsevaa käsitetutkimusta, jolle on ominaista, ettei tutkija ole vuorovaikutuksessa aineiston tuottajan kanssa. Työ oli luonteeltaan teoreettinen, kuvaileva ja laadullinen Tutkimuksen aineistona toimi neljä omistajalähtöistä johtamista käsittelevää teosta, joista kahdessa annettiin kokonaiskuva omistajalähtöisestä johtamisesta, yhdessä aihetta lähestyttiin arvonmäärityksen näkökulmasta ja yhdessä riskien-hallinnan näkökulmasta. Strategiaviitekehys muodostettiin käyttäen hyväksi Chaffeen kolmea, Mintzbergin yhdeksää sekä Volberda ja Elfringin kolmea koulukuntaa. Koulukuntajakoa hyödynnettiin strategisen johtamisen historiallisiin taustoihin tutustumisessa. Yrityksen arvonmääritykselle muodostettiin viitekehys strategia-kirjallisuuden määrittelemistä arvostrategioista. Kasvustrategian viiitekehys muodostui monialaistumisesta ja kansainvälistymisstrategiasta. Tutkimustulokset osoittavat, että omistajalähtöisesti johdetun yrityksen kaiken toiminnan lähtökohtana on omistajien varallisuuden kasvattaminen. Omistajien yritykseen kohdistuvat odotukset ovat yrityksen markkina-arvossa. Hallituksen merkitys johdon ja omistajien rajapintana lisääntyy. Johdon palkkiot on kytketty osakekurssiin. Osakkeenomistajat voidaan jakaa kahteen ryhmään: pääomasijoittajiin ja pörssisijoittajiin. Pääomasijoittajat odottavat yritykseltä tasaista kasvua, maltillista osinkopolitiikkaa, kannattavaa liiketoimintaa sekä riskienhallintaa pitkällä aikavälillä. Pörssisijoittajien odotukset ovat yrityksen markkina-arvossa ja pikaisissa voitoissa.
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Diabetic retinopathy is the leading cause of visual loss in individuals under the age of 55. Most investigations into the pathogenesis of diabetic retinopathy have been concentrated on the neural retina since this is where clinical lesions are manifested. Recently, however, various abnormalities in the structural and secretory functions of retinal pigment epithelium that are essential for neuroretina survival, have been found in diabetic retinopathy. In this context, here we study the effect of hyperglycemic and hypoxic conditions on the metabolism of a human retinal pigment epithelial cell line (ARPE-19) by integrating quantitative proteomics using tandem mass tagging (TMT), untargeted metabolomics using MS and NMR, and 13C-glucose isotopic labeling for metabolic tracking. We observed a remarkable metabolic diversification under our simulated in vitro hyperglycemic conditions of diabetes, characterized increased flux through polyol pathways and inhibition of the Krebs cycle and oxidative phosphorylation. Importantly, under low oxygen supply RPE cells seem to consume rapidly glycogen storages and stimulate anaerobic glycolysis. Our results therefore pave the way to future scenarios involving new therapeutic strategies addressed to modulating RPE metabolic impairment, with the aim of regulating structural and secretory alterations of RPE. Finally, this study shows the importance of tackling biomedical problems by integrating metabolomic and proteomics results.
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The synthesis of 1-deoxy-D-xylulose 5-phosphate (DXP), catalyzed by the enzyme DXP synthase (DXS), represents a key regulatory step of the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for isoprenoid biosynthesis. In plants DXS is encoded by small multigene families that can be classified into, at least, three specialized subfamilies. Arabidopsis thaliana contains three genes encoding proteins with similarity to DXS, including the well-known DXS1/CLA1 gene, which clusters within subfamily I. The remaining proteins, initially named DXS2 and DXS3, have not yet been characterized. Here we report the expression and functional analysis of A. thaliana DXS2. Unexpectedly, the expression of DXS2 failed to rescue Escherichia coli and A. thaliana mutants defective in DXS activity. Coherently, we found that DXS activity was negligible in vitro, being renamed as DXL1 following recent nomenclature recommendation. DXL1 is targeted to plastids as DXS1, but shows a distinct expression pattern. The phenotypic analysis of a DXL1 defective mutant revealed that the function of the encoded protein is not essential for growth and development. Evolutionary analyses indicated that DXL1 emerged from DXS1 through a recent duplication apparently specific of the Brassicaceae lineage. Divergent selective constraints would have affected a significant fraction of sites after diversification of the paralogues. Furthermore, amino acids subjected to divergent selection and likely critical for functional divergence through the acquisition of a novel, although not yet known, biochemical function, were identified. Our results provide with the first evidences of functional specialization at both the regulatory and biochemical level within the plant DXS family.
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Cette contribution questionne l'influence de la littérature d'éducation sur les pratiques éducatives familiales. Les injonctions des pédagogues en faveur de l'observation promeuvent l'usage de journaux d'éducation à l'instar de celui rédigé par René-Guillaume-Jean Prevost-Dassier entre 1789 et 1807. Ce journal permet d'analyser la réception des écrits de J. Locke et J.-J. Rousseau et la façon dont ils conditionnent l'éducation que ce notaire genevois dispense à ses deux enfants.
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Les radiolaires sont des unicellulaires planctoniques qui peuplent nos océans depuis plus de 500 millions d'années. Ces microorganismes développent un squelette en silice ayant des géométries extrêmement diversifiées et sophistiqués qui varient rapidement à l'échelle géologique et permettent de construire des échelles biochronologiques basées sur les différents assemblages qui se succèdent dans le temps. On retrouve ces organismes à l'état fossile dans les roches ma¬rines siliceuse desquelles on peut les extraire avec de l'acide. Des échantillons provenant du sultanat d'Oman et de Sicile ont été étudiés afin de mieux com¬prendre les relations de parenté entre les groupes et de comparer les faunes avec celles du même âge venant de Colombie britannique, du Japon et de Turquie, qui sont représentatives de divers domaines océaniques de l'époque. Certains radiolaires possèdent un anneau autour de leur coque centrale sphérique et ont ainsi été baptisés Saturnalides. Il y a 215 millions d'années, au Norien moyen, ce groupe se diversifie soudainement et donne naissance à une multitude d'espèces qui évoluent rapidement ce qui a permis d'établir des subdivisions temporelles supplémentaires et d'affiner les zonations exis¬tantes. L'étude détaillée de formes intermédiaires entre les espèces a permis d'établir de nouveaux liens de parenté et de considérer le genre Praehexasaturnalis comme l'ancêtre probable de nom¬breuses formes dans le Norien moyen et supérieur. Grâce à l'étude comparative des espèces de Saturnalidae allant du Mésozoïque au Cénozoïque, un certain type d'asymétrie de l'anneau a pu être identifiée comme étant propre à cette famille et plus précisément liée à la disposition de la coque la plus interne (microsphère). Deux nouveaux genres, Blechschmidtia et Tjerkium, s'inscrivent dans une lignée parallèle au Saturnalidae. Cette lignée met en évidence la formation au cours du temps d'un anneau à partir de la fusion de deux épines opposées. -- Late Triassic marine deposits of the Tethyan realm have been investigated in the Sultanate of Oman and in Sicily in order to contribute to the knowledge of radiolarian taxonomy and bio- stratigraphy of this key period preceding the Triassic-Jurassic boundary. In the middle Norian, the saturnalid radiolarians display intense diversification. This blooming of fast evolving spe¬cies has been used to establish a new zonation based on evolutionary successions that refine the existing zonal schemes. One new genus and 16 new species are described. The chronologic distribution of 172 species belonging to 72 genera is established from five sections in the Umar and Al Aridh units of the Hawasina Basin. Many Late Triassic saturnalid species are interpreted to originate from the genus Praehexasaturnalis Kozur & Mostler, which shows strong morpho¬logical diversification patterns. Detailed comparative studies of different types of asymmetric ring morphologies of Mesozoic to Cainozoic saturnalid species permitted to relate the origin of the asymmetry to the disposition of the initial skeletal structure and to gain new insight on the internal and external geometrical transformations of this group trough time and how the emergence of new families is induced by environmental stress. RÉSUMÉ Les formations marines du Trias supérieur du domaine téthysien ont été étudiées dans le Sultanat d'Oman et en Sicile afin de contribuer à la connaissance et au développement de la taxonomie et de la biostratigraphie des radiolaires de cette période clé qui précède la crise de la limite Trias-Jurassique. Au Norien moyen, les radiolaires Saturnalides montrent une intense diversi¬fication. Ce véritable "bloom" d'espèces qui évoluent rapidement a été utilisé pour l'établisse¬ment d'une nouvelle zonation basée sur les successions évolutives de ce groupe qui permettent d'affiner les subdivisions biochronologiques existantes. Un nouveau genre et seize nouvelles espèces sont décrits. La distribution stratigraphique de 172 espèces appartenant à 72 genres est établie pour 5 sections dans les unités d'Umar et d'Al Aridh du bassin de Hawasina. Un essai d'établissement d'une phylogénèse des Saturnalidae du Trias supérieur mène à proposer que le genre Praehexasaturnalis Kozur & Mostler est l'ancêtre de beaucoup d'espèces de Saturnalidae du Trias supérieur. L'étude comparative détaillée des différents types d'asymétrie de l'anneau chez les Saturnali¬dae du Mésozoïque au Cénozoïque a permis de lier l'origine de ce phénomène à la disposition de la structure initiale de leur squelette et par ce fait d'avoir une meilleure compréhension des transformations géométriques internes et externes subies par ce groupe au cours du temps et de concevoir comment l'émergence de nouvelles familles est induite lors de périodes de stress environnemental.
Resumo:
Sähkömarkkinaosapuolet ovat havainneet lukuisia puutteita ja haasteita tietojärjestelmien tiedonvaihtoon liittyvissä kysymyksissä. Tässä työssä käsitellään tiedonvaihdon ongelmaa mittausvirtojen kannalta. Tiedonvaihdon lisääntyminen ja sanomien monipuolistuminen on johtanut siihen, että läheskään kaikki tarpeelliset sanomat eivät ole standardoitu, ja jo luoduissa tai ehdotetuissa standardeissa on huomattavia eroavaisuuksia mm. eri maiden välillä. Tässä työssä kuvataan nykyinen automaattisen mittarinlukujärjestelmän ja jakeluverkkoyhtiön mittaustietovaraston välinen tiedonvaihtoratkaisu ja siihen liittyvät mittaustietovirrat. Työssä esitellään myös älykkäiden mittarien tuomia hyötyjä ja pohditaan uusien mittausten tuomia mahdollisuuksia. Lisäksi pohditaan nykyisten tietovirtojen koodituskäytäntöjen toimivuutta ja niiden puutteita ja ongelmia. Työssä laaditaan esimerkki standardi mittausvirtakonfiguraation mallintamiseksi sähkömarkkinoilla. Työn painopiste on energiamittaustietojen tietovirroissa lähtien laskutuksen tarpeista. Tavoitteena on automaattisten mittarinhallintaprojektien tuomien älykkäiden mittarien uusien mittausten aiheuttaman ja mahdollistaman tietovirran standardointi. Työssä pohditaan, kuinka tietovirta saadaan eheästi siirtymään mittauspalveluntarjoajan ja jakeluverkkoyhtiön järjestelmien välillä sekä miten uudet tiedonkäyttötarpeet tulisi koodittaa. Uudet sanomastandardiehdotukset esitetään XML-mallein, ja lopuksi pohditaan mallien toimivuutta ja niihin tarvittavia jatkokehitystarpeita.
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This PhD study aims to exploit the rich archive provided by the Miocene mollusc fauna of the Pebas Formation and other inland Miocene Amazonian formations to reconstruct landscape evolution and biotic development in lowland Amazonia during the Neogene. Over 160 samples from more than 70 Pebas Formation outcrops mostly collected by the author were processed for this study. Additional samples were collected in Andean areas of Colombia and Venezuela and further material from other northwestern South American basins was studied in museums. Pebas Formation samples and well log data made available by Occidental Peru from three wells in the Marañon Basin in Peru were also investigated. During this study four genera and 74 species from the Pebas Formation have been described and a further 13 species have been introduced in open nomenclature, and several species were reported for the first time. The number of mollusc species attributed to the Pebas fauna has increased from around 50 to 156. The Pebas fauna is characterised as aquatic, endemic and extinct, and is a typical representative of a long-lived lake fauna. Fluvial taxa are not common, (marginal) marine taxa are rare. An additional molluscan fauna from the Miocene Solimões Formation of Brazil, containing 13 fresh water species was also described. The newly documented fauna was used to improve biostratigraphic framework of Miocene Amazonian deposits. Twelve mollusc zones were introduced, the upper eleven of which cover a time interval of approximately seven million years covered previously by only three pollen zones. An age model calculated for the borehole data indicates that the Pebas Formation was deposited between c. 24 and 11 Ma. The areal distribution of the outcropping mollusc zones uncovered a broad dome structure, termed here the Iquitos-Araracuara anteclise in the study area. The structure appears to have influenced river courses and also contributed to edaphic heterogeneity that may have been in part responsible for the current high biodiversity in the study area. The Pebas system was a huge system (> one million km2) dominated by relatively shallow lakes, but also containing swamps and rivers. The system was fed by rivers draining the emergent Andes in the west and lowlands and cratons to the east. The Pebas system was located at sea level and was open to marine settings through a northern portal running through the Llanos Basin and East Venezuela Basin towards the Caribbean. Cyclical baselevel changes possibly related to Mylankhovitch cycles, have been documented in depositional sequences of the Pebas Formation. The composition of the Pebasian mollusc fauna implies that the system was mostly a fresh water system. Such an interpretation is matched by strontium isotope ratios as well as very negative δ18O ratios found in the shells, but is at odds with oligohaline and mesohaline ichnofacies found in the same strata. The mollusc fauna of the Pebas Formation diversified through most of the existence of the lake system. The diversification was mostly the result of in-situ cladogenesis. The success of some of the Pebasian endemic clades is explained by adaptation to fresh water, low oxygen, common unconsolidated lake bottoms (soup grounds) as well as high predation intensity. Maximum diversity was reached at the base of the late Middle to early Late Miocene Grimsdalea pollen zone, some 13 Ma. At the time some 85 species co-occurred, 67 of which are considered as Pebasian endemics. A subsequent drop in species richness coincides with indications of elevated salinities, although a causal relation still needs to be established. Apparently the Pebas fauna went (almost) entirely extinct with the replacement of the lake system into a fluvio-tidal system during the Early Late Miocene, some 11 Ma.
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The genome of the bladderwort Utricularia gibba provides an unparalleled opportunity to uncover the adaptive landscape of an aquatic carnivorous plant with unique phenotypic features such as absence of roots, development of water-filled suction bladders, and a highly ramified branching pattern. Despite its tiny size, the U. gibba genome accommodates approximately as many genes as other plant genomes. To examine the relationship between the compactness of its genome and gene turnover, we compared the U. gibba genome with that of four other eudicot species, defining a total of 17,324 gene families (orthogroups). These families were further classified as either 1) lineage-specific expanded/contracted or 2) stable in size. The U. gibba-expanded families are generically related to three main phenotypic features: 1) trap physiology, 2) key plant morphogenetic/developmental pathways, and 3) response to environmental stimuli, including adaptations to life in aquatic environments. Further scans for signatures of protein functional specialization permitted identification of seven candidate genes with amino acid changes putatively fixed by positive Darwinian selection in the U. gibba lineage. The Arabidopsis orthologs of these genes (AXR, UMAMIT41, IGS, TAR2, SOL1, DEG9, and DEG10) are involved in diverse plant biological functions potentially relevant for U. gibba phenotypic diversification, including 1) auxin metabolism and signal transduction, 2) flowering induction and floral meristem transition, 3) root development, and 4) peptidases. Taken together, our results suggest numerous candidate genes and gene families as interesting targets for further experimental confirmation of their functional and adaptive roles in the U. gibba's unique lifestyle and highly specialized body plan.
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Last two decades have seen a rapid change in the global economic and financial situation; the economic conditions in many small and large underdeveloped countries started to improve and they became recognized as emerging markets. This led to growth in the amounts of global investments in these countries, partly spurred by expectations of higher returns, favorable risk-return opportunities, and better diversification alternatives to global investors. This process, however, has not been without problems and it has emphasized the need for more information on these markets. In particular, the liberalization of financial markets around the world, globalization of trade and companies, recent formation of economic and regional blocks, and the rapid development of underdeveloped countries during the last two decades have brought a major challenge to the financial world and researchers alike. This doctoral dissertation studies one of the largest emerging markets, namely Russia. The motivation why the Russian equity market is worth investigating includes, among other factors, its sheer size, rapid and robust economic growth since the turn of the millennium, future prospect for international investors, and a number of important major financial reforms implemented since the early 1990s. Another interesting feature of the Russian economy, which gives motivation to study Russian market, is Russia’s 1998 financial crisis, considered as one of the worst crisis in recent times, affecting both developed and developing economies. Therefore, special attention has been paid to Russia’s 1998 financial crisis throughout this dissertation. This thesis covers the period from the birth of the modern Russian financial markets to the present day, Special attention is given to the international linkage and the 1998 financial crisis. This study first identifies the risks associated with Russian market and then deals with their pricing issues. Finally some insights about portfolio construction within Russian market are presented. The first research paper of this dissertation considers the linkage of the Russian equity market to the world equity market by examining the international transmission of the Russia’s 1998 financial crisis utilizing the GARCH-BEKK model proposed by Engle and Kroner. Empirical results shows evidence of direct linkage between the Russian equity market and the world market both in regards of returns and volatility. However, the weakness of the linkage suggests that the Russian equity market was only partially integrated into the world market, even though the contagion can be clearly seen during the time of the crisis period. The second and the third paper, co-authored with Mika Vaihekoski, investigate whether global, local and currency risks are priced in the Russian stock market from a US investors’ point of view. Furthermore, the dynamics of these sources of risk are studied, i.e., whether the prices of the global and local risk factors are constant or time-varying over time. We utilize the multivariate GARCH-M framework of De Santis and Gérard (1998). Similar to them we find price of global market risk to be time-varying. Currency risk also found to be priced and highly time varying in the Russian market. Moreover, our results suggest that the Russian market is partially segmented and local risk is also priced in the market. The model also implies that the biggest impact on the US market risk premium is coming from the world risk component whereas the Russian risk premium is on average caused mostly by the local and currency components. The purpose of the fourth paper is to look at the relationship between the stock and the bond market of Russia. The objective is to examine whether the correlations between two classes of assets are time varying by using multivariate conditional volatility models. The Constant Conditional Correlation model by Bollerslev (1990), the Dynamic Conditional Correlation model by Engle (2002), and an asymmetric version of the Dynamic Conditional Correlation model by Cappiello et al. (2006) are used in the analysis. The empirical results do not support the assumption of constant conditional correlation and there was clear evidence of time varying correlations between the Russian stocks and bond market and both asset markets exhibit positive asymmetries. The implications of the results in this dissertation are useful for both companies and international investors who are interested in investing in Russia. Our results give useful insights to those involved in minimising or managing financial risk exposures, such as, portfolio managers, international investors, risk analysts and financial researchers. When portfolio managers aim to optimize the risk-return relationship, the results indicate that at least in the case of Russia, one should account for the local market as well as currency risk when calculating the key inputs for the optimization. In addition, the pricing of exchange rate risk implies that exchange rate exposure is partly non-diversifiable and investors are compensated for bearing the risk. Likewise, international transmission of stock market volatility can profoundly influence corporate capital budgeting decisions, investors’ investment decisions, and other business cycle variables. Finally, the weak integration of the Russian market and low correlations between Russian stock and bond market offers good opportunities to the international investors to diversify their portfolios.
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Tässä tutkielmassa tarkastellaan suomalaisen sijoitusportfolion hajauttamista asuinkiinteistöihin. Tutkielman tavoitteena on selvittää, pystyykö hajauttamisella tehostamaan portfoliota sekä tutkia kaupungin ja kokoluokan merkitystä kiinteistöihin hajauttamisessa. Tutkimusaineisto koostuu Suomen osakemarkkinoita kuvaavista toimialaindeksistä sekä asuinkiinteistöindekseistä. Asuinkiinteistöt ovat jaoteltu sekä kaupungeittain että kokoluokittain. Tutkimusaineisto on aikaperiodilta 1988Q3-2008Q3. Tutkimustulosten mukaan kiinteistöihin hajauttamisella voidaan tehostaa portfoliota. Varsinkin pienemmillä tuottotasoilla kiinteistöihin sijoitetaan merkittävästi. Korkeammilla tuottovaatimuksilla kiinteistösijoitus ei tuonut lisäarvoa portfolion hajautukseen.
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Tutkielman tavoitteena oli selvittää, kuinka muutosvaiheessa oleva elektroniikkateollisuuden ala vaikuttaa siinä mukana olevien pienten ja keskisuurten sopimusvalmistaja yritysten tulevaisuuden kasvustrategioihin Tutkielmassa päädyttiin tarkastelemaan seuraavia kasvustrategioita: markkinapenetraatio, tuotekehitys yhdessä asiakkaan kanssa, markkinakehitys ja diversifikaatio. Tutkielmassa määriteltiin myös kasvustrategioihin yleisesti vaikuttavat tekijät, joita käsiteltiin empiriassa pk-sopimusvalmistajan näkökulmasta. Esitettyjä kasvustrategioita peilattiin elektroniikkateollisuuden tulevaisuuden näkymiin skenaariotyöskentelyä hyödyntäen. Erityisesti yrityksen sopimusvalmistajaroolin todettiin vaikuttavan niin kasvustrategioihin kuin valittua strategiaa toteuttaviin kasvukeinoihin. Tutkimuksessa käytettiin laadullista eli kvalitatiivista tutkimusotetta. Tutkimusmenetelmäksi puolestaan valittiin tapaus eli case-tutkimus. Kohdeyrityksen avulla pyrittiin luomaan syvempää ymmärrystä pk-sopimusvalmistajan resursseista, kyvykkyyksistä ja haasteista.
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Inversors però, principalment professionals de l'àmbit agrari, per tal de buscar una diversificació de l'activitat agrícola i ramadera que desenvolupen a les seves finques, sobretot joves emprenedors, poden estar interessats en produccions alternatives com la producció d'ànecs per a foie-gras, per tal de complementar la seva renda agrària. Actualment cal augmentar la competitivitat de les finques agrícoles per tal que aquestes siguin econòmicament viables. L’objectiu de l'estudi és determinar la viabilitat econòmica d’una explotació ramadera d’ànecs per a la producció de foie-gras, en el terme municipal de Fontanals de Cerdanya, analitzant les diverses alternatives en quant a dimensionament i disseny de les instal·lacions, segons el cicle productiu de l’animal. L'alternativa escollida per realitzar l'estudi es la de semi-integració (cria, engreix i embocat), de règim semi-intensiu (durant l'etapa de l'engreix), amb animals mascles de la raça híbrida Mulard. Les instal·lacions tindran una capacitat de 6.500 animals, amb lots de 250 caps. Aquest dimensionament permet, durant la fase d'embocat, en la qual es requereix més dedicació, que la demanda de mà d'obra pugui ser satisfeta per un únic treballador. La principal conclusió que es pot extreure de l'estudi és que la inversió projectada és massa elevada i que aquesta econòmicament no és viable o rendible, ja que la despesa és massa elevada. Es mouen uns fluxos de caixa molt elevats i el marge comercial és molt reduït. Únicament si l'objectiu del promotor és obtenir una remuneració per la seva feina, sempre i quan és produeixi un augment del preu actual de la carn i una disminució del preu del pinso, es podria recomanar que es portés a terme la implantació de l'explotació, intentant, però, reduir la despesa d'execució de construccions i instal·lacions.
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The natural rubber is a strategic material which can not be replaced by synthetic rubber in many technological applications. Brazil is a rubber importer, but new techniques of cultivation, breeding and diversification of producing species can reverse this situation. One of the best ways to add value to this commodity is nanotechnology. The production of nanocomposites is already a reality and shows that the sustainable use of this natural resource can lead to new products and boost the national agribusiness setting labor-qualified in the field.
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The AIDS epidemy has spread out and led to the diversification on the research for new antiviral drugs. Natural products, especially those derived from plants, are well-recognized as excellent sources of new drugs. Several of them have inhibitory activity against HIV replication, and some have been already clinically tested, with favorable results. This review presents the biochemical basis of the viral cycle and the research up to date on the identification, determination of the mechanism of biological action together with the therapeutical potential of plants-derived natural products, in the inhibition of HIV.