1,353 research outputs found

    Nonlinearities and synchronization of business cycles : a novel approach

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    Mestrado em EconomiaEsta disserta√ß√£o estuda os padr√Ķes de sincroniza√ß√£o de ciclos econ√≥micos numa amostra composta por 18 pa√≠ses desenvolvidos e a Zona Euro ao longo do per√≠odo 1970:1-2008:1. Para realizar este estudo, propomos um novo modelo de componentes n√£o observ√°veis multivariado com markov-switching e interdepend√™ncia de estados vari√°vel no tempo, no qual a sincroniza√ß√£o √© modelizada como uma componente comum vari√°vel no tempo entre os ciclos econ√≥micos. Para estimar o modelo, desenvolvemos um filtro de Kalman adequado, que permite a projec√ß√£o das componentes n√£o observ√°veis e a estima√ß√£o dos hiperpar√Ęmetros por m√°xima verosimilhan√ßa. Propomos tamb√©m um novo fullsample smoother para recalcular as componentes n√£o observ√°veis do modelo com base em toda a informa√ß√£o amostral. Usamos este modelo para testar 3 hip√≥teses: se a cria√ß√£o da Uni√£o Monet√°ria Europeia promoveu um aumento na sincroniza√ß√£o dos ciclos econ√≥micos entre os seus membros; se a integra√ß√£o promoveu uma mudan√ßa na filia√ß√£o c√≠clica com o ciclo econ√≥mico dos EUA; se existe o surgimento de um ciclo econ√≥mico agregado da Zona Euro. Os resultados mostram que a sincroniza√ß√£o c√≠clica dos pa√≠ses da Zona Euro com a Zona Euro agregada foi superior √† dos restantes pa√≠ses. No entanto, para a maioria dos pa√≠ses da Zona Euro, a sincroniza√ß√£o com a Zona agregada aumentou at√© ao in√≠cio da d√©cada de 90, e diminuiu a partir desse per√≠odo. Apesar de existir um ligeiro aumento na sincroniza√ß√£o com a Zona Euro agregada para algumas economias participantes em torno do momento da introdu√ß√£o da moeda √ļnica, n√£o somos capazes de detectar um ‚Äúefeito Euro‚ÄĚ claro. Por outro lado, para a maioria das economias, a introdu√ß√£o da moeda √ļnica √© coincidente com uma redu√ß√£o na sincroniza√ß√£o com o ciclo dos EUA. Finalmente, n√£o encontramos evid√™ncia do surgimento de um ciclo econ√≥mico agregado da Zona Euro. ABSTRACT: This dissertation studies the patterns of business cycle synchronization across a sample of 18 developed countries and the aggregate Euro Area over the period 1970:1-2008:1. To perform this study, we propose a novel multivariate unobservedcomponents model with markov-switching and time-varying state interdependence, in which synchronization is modelled as a time-varying common component between the business cycles. To estimate the model, we develop an adequate Kalman filter, which allows the projection of the unobserved components and the estimation of the hyperparameters by maximum likelihood. We also propose a new full-sample smoother to recompute the unobserved components of the model based on all in-sample information. We use this model to test 3 hypothesis: whether the creation of the European Monetary Union promoted an increase in business cycle synchronization among its members; whether the integration has promoted a change in the cyclical affiliation with the US business cycle; and whether there is an emergence of an aggregate Euro Area business cycle. The results show that synchronization between the Euro Area countries with the aggregate Euro Area has been higher than for the remaining countries. Nevertheless, for the majority of the Euro Area countries, synchronization with the aggregate Area increased until the beginning of the 1990s, and dropped from that period onwards. Moreover, despite the existence of a slight increase in synchronization with the aggregate Euro Area for some participant economies around the timing of the introduction of the common currency, we are not able to uncover a clear ‚ÄúEuro effect‚ÄĚ. On the other hand, for most of the economies, the introduction of the common currency is shown to be coincident with a drop in synchronization with the US business cycle. Finally, we do not find evidence of the emergence of an aggregate Euro-Area business cycle

    Regeneração da barbatana caudal em peixe-zebra (Danio rerio): uma perspectiva biofísica

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    Tese de mestrado. Biologia (Biologia Evolutiva e do Desenvolvimento). Universidade de Lisboa, Faculdade de Ci√™ncias, 2011O peixe-zebra (Danio rerio) regenera v√°rios √≥rg√£os, o que o torna um excelente modelo para estudos de regenera√ß√£o. Partindo de uma hip√≥tese biof√≠sica onde fluxos i√≥nicos e correntes associadas s√£o considerados eventos epigen√©ticos √† regenera√ß√£o, determinou-se o perfil de fluxos extracelulares dos i√Ķes cloreto e s√≥dio na barbatana caudal durante as diferentes fases da regenera√ß√£o. Como esperado, imediatamente ap√≥s a amputa√ß√£o observou-se uma sa√≠da massiva destes i√Ķes. Ap√≥s o fecho da ferida, ambos os perfis de fluxos de cloreto e s√≥dio revelaram padr√Ķes din√Ęmicos que acompanham a regenera√ß√£o. Embora n√£o tenha sido detectado qualquer influxo de s√≥dio durante e ap√≥s a forma√ß√£o do blastema, como postulado noutros sistemas, a inibi√ß√£o farmacol√≥gica de canais de s√≥dio perturbou a regenera√ß√£o, indicando que este i√£o √© importante no mecanismo. Dada a aus√™ncia de influxo de s√≥dio, o efluxo de cloreto emergiu assim como prov√°vel respons√°vel pela corrente de entrada caracter√≠stica dos sistemas regenerantes. Foram ainda detectados tr√™s padr√Ķes bioel√©ctricos interessantes: (1) um padr√£o raio/inter-raio; (2) um poss√≠vel padr√£o centro/extremidade da barbatana; e (3) uma diferen√ßa do padr√£o de fluxos entre amputa√ß√£o proximal e distal. Estes padr√Ķes poder√£o conter informa√ß√£o mitog√©nica e morfog√©nica. Estes resultados parecem apoiar a ideia de que os mecanismos bioel√©ctricos t√™m um papel importan-te e conservado na regula√ß√£o da regenera√ß√£o.Zebrafish (Danio rerio) regenerates several organs, rendering it an excellent regeneration model. Starting from a biophysical hypothesis where ionic fluxes and associated currents are considered epi-genetic events to regeneration, the extracellular flux profiles for chloride and sodium were determined in the caudal fin during different stages of regeneration. As expected, immediately after amputation there was a massive outflow of these ions. After wound closure, both profiles of chloride and sodium fluxes showed dynamic patterns that accompany regeneration. Although no sodium influx was detected during and after blastema formation, as postulated in other systems, pharmacological inhibition of sodium chan-nels perturbed regeneration, pointing to a role for this ion in the regeneration mechanism. Given the ab-sence of sodium influx, chloride efflux thus emerges as the putative ion responsible for the inward current characteristic of regenerating systems. Three interesting bioelectric patterns have been detected: (1) a parttern ray/inter-ray; (2) a possible pattern center/extremity of the fin; and (3) a difference in the pattern of fluxes between the proximal and distal amputation. These patterns may contain mitogenic and morpho-genic information. These results seem to support the idea that the bioelectric mechanisms do play an important and conserved role in regulating regeneration

    Cost-efficiency improvement of bivalves shells preparation when tracing their geographic origin through ICP-MS analysis of elemental fingerprints

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    Developing methodologies employed to trace the geographic origin of seafood as accurate and fast as possible can help to speed-up the delivery of results to legal authorities, reduce associated costs and minimize environmental impacts (associated with the residues generated). The present study evaluated if trace element fingerprints (TEF) of a small homogenized subsample of Manila clams (Ruditapes philippinarum) right valve yielded a representative elemental signature of the whole shell. Four elemental ratios (Ba/Ca, Mg/Ca, Mn/Ca and Sr/Ca) commonly employed to trace the geographic origin of bivalves were determined from subsamples of 0.2 and 3 g of the homogenized right valve and the whole left valve (4 g). A Canonical Analysis of Principal Coordinates developed for the subsamples of small portions (0.2 g) of the homogenized right valve revealed an accuracy of 100%, that led to the correct classification of the subsample of 3 g to their respective valve and that of 4 g to its matching shell. Results achieved indicate that TEF of a small homogenized portion of a bivalves valve is representative of the whole shell and can be employed to provide an accurate, fast, reliable and environmentally safer method to trace its geographic origin.publishe

    Successful use of geochemical tools to trace the geographic origin of Long-Snouted Seahorse Hippocampus guttulatus raised in captivity

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    The global market of dried seahorses mainly supplies Traditional Chinese Medicine and still relies on blurry trade chains that often cover less sustainable practices targeting these pricey and endangered fish. As such, reliable tools that allow the enforcement of traceability, namely to confirm the geographic origin of traded seahorses, are urgently needed. The present study evaluated the use of elemental fingerprints (EF) in the bony structures of long-snouted seahorses Hippocampus guttulatus raised in captivity in two different locations (southern Portugal and Northern Spain) to discriminate their geographic origin. The EF of different body parts of H. guttulatus were also evaluated as potential proxies for the EF of the whole body, in order to allow the analysis of damaged specimens and avoid the use of whole specimens for analysis. The contrasting EF of H. guttulatus raised in the two locations allowed their reliable discrimination. Although no single body part exactly mimicked the EF of the whole body, seahorse trunks, as well as damaged specimens, could still be correctly allocated to their geographic origin. This promising forensic approach to discriminate the geographic origin of seahorses raised in captivity should now be validated for wild conspecifics originating from different locations, as well as for other species within genus Hippocampus.PTDC/BIA-BMA/29491/2017, UIDB/04326/2020, UIDP/50017/2020, UIDB/50017/2020,info:eu-repo/semantics/publishedVersio

    INTERA√á√ÉO DO L√ćQUEN Cladonia verticillaris COM SOLO DE SUA √ĀREA DE OCORR√äNCIA

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    Liquens produzem subst√Ęncias capazes de interagir com seu substrato rochoso ou solo modificando-os quimicamente, formando quelatos. Quando sob a influ√™ncia de fonte ex√≥gena de nitrog√™nio, algumas esp√©cies produzem suas subst√Ęncias em maior teor, incrementando a percola√ß√£o desses produtos, favorecendo a intera√ß√£o com seu substrato. Neste trabalho avaliou-se a capacidade do l√≠quen Cladonia verticillaris interagir com o solo de sua √°rea de ocorr√™ncia e, a poss√≠vel interfer√™ncia de fonte nitrogenada na forma de ur√©ia como ativadora da s√≠ntese de subst√Ęncias modificadoras desse substrato. Experimentos foram montados com amostras do l√≠quen e solo a elas subjacente, que foram periodicamente, at√© 150 dias, analisados a partir de seus extratos brutos por cromatografia em camada delgada. Os resultados demonstraram que o l√≠quen produziu seu principal composto, o √°cido fumarprotocetr√°rico (FUM), por todo o per√≠odo. A fonte nitrogenada influenciou no aumento da s√≠ntese do FUM, bem como ac√ļmulo de subst√Ęncias intermedi√°rias de sua bioss√≠ntese. Estas subst√Ęncias foram tamb√©m encontradas nas amostras de solo, tanto na forma natural como oxidadas ou reduzidas, indicando intera√ß√£o de C. verticillaris com seu substrato. Este teve seu pH diminu√≠do e modifica√ß√£o nos teores de Al e H, sobretudo nos experimentos sob influ√™ncia da ur√©ia

    Estimativa de popula√ß√Ķes canina e felina domiciliadas em zona urbana do Estado de S√£o Paulo

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    OBJECTIVE: Given the importance of assessing owned dog and cat populations to adequate planning and evaluation of rabies control measures in urban areas, it is proposed the use of an estimate of these populations based on human population parameters. METHODS: The ratio between human population and owned animal (dogs and cats) population was calculated in the municipality of Tabo√£o da Serra, state of S√£o Paulo, Brazil. This municipality was divided into two distinct social and economic homogeneous areas through k-mean algorithm, allowing for comparison between the ratios of the two homogeneous areas. RESULTS: A 5.14 ratio was calculated for human and dog populations and a 30.57ratio for human and feline populations. A significant difference was not observed when comparing the ratios for human and animal populations of the two homogeneous areas. CONCLUSIONS: An estimate of owned dog and cat populations based on the human population is the better choice for assessing the animal population instead of an animal census because it can be easily implemented.OBJETIVO: Dada a import√Ęncia do conhecimento acerca da popula√ß√£o de c√£es e gatos domiciliados para o adequado planejamento e avalia√ß√£o das a√ß√Ķes de controle da raiva em √°reas urbanas, prop√Ķe-se a utiliza√ß√£o de um valor preciso de estimativa dessas popula√ß√Ķes com base em indicadores populacionais humanos. M√ČTODOS: Foi calculada a raz√£o entre as popula√ß√Ķes humana e animal (canina e felina) por meio de inspe√ß√Ķes domiciliares, no Munic√≠pio de Tabo√£o da Serra, SP. O munic√≠pio foi dividido em duas √°reas homog√™neas distintas socioeconomicamente, de acordo com o algoritmo da m√©dia k, de modo a permitir a compara√ß√£o das raz√Ķes homem:animal (c√£o e gato) das √°reas homog√™neas. RESULTADOS: A raz√£o entre a popula√ß√£o humana e a popula√ß√£o canina foi 5,14 e a entre a humana e a felina foi 30,57. N√£o foi observada diferen√ßa significativa ao comparar-se as raz√Ķes entre as popula√ß√Ķes humana e animal das √°reas homog√™neas. CONCLUS√ēES: A ado√ß√£o de uma metodologia de estimativa populacional canina e felina domiciliada, baseada em indicadores populacionais humanos, √© a mais indicada e facilmente exeq√ľ√≠vel quando comparada ao censo canino

    Herbicidas com potencial para dessecação em pré-semeadura na cultura do algodão

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    Although efficient, there are few options for selective herbicides applied in pre-emergence for cotton cultivation, with applications being carried out with products that result, in some situations, in phytotoxicity in the culture and resulting in low fiber quality and cotton yield. Therefore, the objective was to determine potential herbicides to replace paraquat, to be used in the desiccation of areas in pre-sowing of the cotton crop, evaluating the carryover effect. The experiment was carried out in the experimental area of the Teaching and Research Farm (FEPE), belonging to UniBRAS ‚Äď Faculdade Rio Verde. The experimental design used was in randomized blocks in a 9x3 factorial scheme with four replications, consisting of nine treatments and three times of application of the treatments (14, 7 and 0 days before sowing) in the cotton crop. At 35 days after sowing, biometric and physiological evaluations of the culture were performed. The data obtained were submitted to analysis of variance and the cases of significance were analyzed using the Tukey mean comparison test (p<0.05). Glufosinate applied alone and the mixtures between Glufosinate + Glyphosate and Carfentrazone + Glyphosate showed promise as potential herbicides to replace paraquat, to be used in the desiccation of areas in pre-sowing of the cotton crop under the conditions of this test.Aunque eficientes, existen pocas opciones de herbicidas selectivos aplicados en preemergencia para el cultivo del algod√≥n, realiz√°ndose aplicaciones con productos que resultan, en algunas situaciones, en fitotoxicidad en el cultivo y resultan en baja calidad de fibra y rendimiento de algod√≥n. Por lo tanto, el objetivo fue determinar herbicidas potenciales para reemplazar al paraquat, para ser utilizados en la desecaci√≥n de √°reas en presiembra del cultivo de algod√≥n, evaluando el efecto arrastre. El experimento fue realizado en el √°rea experimental de la Granja de Ense√Īanza e Investigaci√≥n (FEPE), perteneciente a la UniBRAS ‚Äď Faculdade Rio Verde. El dise√Īo experimental utilizado fue en bloques al azar en esquema factorial 9x3 con cuatro repeticiones, constando de nueve tratamientos y tres tiempos de aplicaci√≥n de los tratamientos (14, 7 y 0 d√≠as antes de la siembra) en el cultivo de algod√≥n. A los 35 d√≠as despu√©s de la siembra se realizaron evaluaciones biom√©tricas y fisiol√≥gicas del cultivo. Los datos obtenidos se sometieron a an√°lisis de varianza y los casos de significancia se analizaron mediante la prueba de comparaci√≥n de medias de Tukey (p<0,05). El Glufosinato aplicado solo y las mezclas entre Glufosinato + Glifosato y Carfentrazona + Glifosato se mostraron prometedores como herbicidas potenciales para reemplazar al paraquat, para ser utilizados en la desecaci√≥n de √°reas en presiembra del cultivo de algod√≥n bajo las condiciones de esta prueba.Apesar de eficientes, h√° poucas op√ß√Ķes de herbicidas seletivos aplicados em pr√©-emerg√™ncia para a cultua do algod√£o, sendo realizadas aplica√ß√Ķes com produtos que resultam, em algumas situa√ß√Ķes, em fitotoxidade na cultura e resultando em uma baixa qualidade de fibra e rendimento do algodoeiro. Portanto, objetivou-se determinar potenciais herbicidas em substitui√ß√£o ao paraquat, para serem utilizados na desseca√ß√£o de √°reas em pr√©-semeadura da cultura do algod√£o, avaliando-se o efeito carryouver. O experimento foi conduzido na √°rea experimental da Fazenda de Ensino e Pesquisa (FEPE), pertencente √† UniBRAS ‚Äď Faculdade Rio Verde. O delineamento experimental utilizado foi em blocos casualizados em esquema fatorial 9x3 com quatro repeti√ß√Ķes, composto por nove tratamentos e tr√™s √©pocas de aplica√ß√£o dos tratamentos (14, 7 e 0 dias antes da semeadura) na cultura do algod√£o. Aos 35 dias ap√≥s a semeadura foi realizada avalia√ß√Ķes biom√©tricas e fisiol√≥gicas da cultura. Os dados obtidos foram submetidos a an√°lise de vari√Ęncia e os casos de signific√Ęncia foram analisados pelo teste de compara√ß√£o de m√©dia Tukey (p<0,05). O Glufosinate aplicado isolado e as misturas entre Glufosinato + Glyphosate e Carfentrazona + Glyphosate mostraram-se promissores como potenciais herbicidas em substitui√ß√£o ao paraquat, para serem utilizados na desseca√ß√£o de √°reas em pr√©-semeadura da cultura do algod√£o nas condi√ß√Ķes deste ensaio

    Investigação sobre brucelose bovina na Ilha de Fernando de Noronha, Pernambuco, Brasil

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    Considering the lack of information about livestock diseases on Brazilian oceanic islands, the occurrence of bovine brucellosis was investigated on the island of Fernando de Noronha, state of Pernambuco, Brazil. Serum samples were collected in October 2009, from all the 105 cows raised on the island at that time. These were examined concurrently using the Rose Bengal test and the Complement Fixation Test. All the samples were negative in both tests, indicating that the cows on the island were likely free from infection by smooth forms of Brucella. These results can partly be explained by the prohibition of introduction and importation of both small and large-sized animals that had been implemented through District Decree 19 of February 28, 2004.Tendo em vista a inexist√™ncia de informa√ß√Ķes sobre a ocorr√™ncia da brucelose bovina em ilhas oce√Ęnicas brasileiras, investigou-se a presen√ßa da infec√ß√£o na ilha de Fernando de Noronha, Estado de Pernambuco, Brasil. Soros de todas as 105 f√™meas bovinas existentes, colhidos em outubro de 2009, foram examinados concomitantemente pelo teste do Ant√≠geno Acidificado Tamponado e pela Rea√ß√£o de Fixa√ß√£o de Complemento. Todas as amostras foram negativas em ambos os testes, indicando que provavelmente os animais presentes na ilha encontravam-se livres da infec√ß√£o por Brucella. Estes resultados podem ser explicados, em partes, pela proibi√ß√£o da introdu√ß√£o e importa√ß√£o de grandes e pequenos animais, implementada pelo Decreto Distrital 19, de 28 de fevereiro de 2004

    Change Detection of Selective Logging in the Brazilian Amazon Using X-Band SAR Data and Pre-Trained Convolutional Neural Networks

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    From MDPI via Jisc Publications RouterHistory: accepted 2021-12-01, pub-electronic 2021-12-05Publication status: PublishedIt is estimated that, in the Brazilian Amazon, forest degradation contributes three times more than deforestation for the loss of gross above-ground biomass. Degradation, in particular those caused by selective logging, result in features whose detection is a challenge to remote sensing, due to its size, space configuration, and geographical distribution. From the available remote sensing technologies, SAR data allow monitoring even during adverse atmospheric conditions. The aim of this study was to test different pre-trained models of Convolutional Neural Networks (CNNs) for change detection associated with forest degradation in bitemporal products obtained from a pair of SAR COSMO-SkyMed images acquired before and after logging in the Jamari National Forest. This area contains areas of legal and illegal logging, and to test the influence of the speckle effect on the result of this classification by applying the classification methodology on previously filtered and unfiltered images, comparing the results. A method of cluster detections was also presented, based on density-based spatial clustering of applications with noise (DBSCAN), which would make it possible, for example, to guide inspection actions and allow the calculation of the intensity of exploitation (IEX). Although the differences between the tested models were in the order of less than 5%, the tests on the RGB composition (where R = coefficient of variation; G = minimum values; and B = gradient) presented a slightly better performance compared to the others in terms of the number of correct classifications for selective logging, in particular using the model Painters (accuracy = 92%) even in the generalization tests, which presented an overall accuracy of 87%, and in the test on RGB from the unfiltered image pair (accuracy of 90%). These results indicate that multitemporal X-band SAR data have the potential for monitoring selective logging in tropical forests, especially in combination with CNN techniques

    Primeiro caso de leishmaniose visceral humana de transmissao autoctone no centro urbano do Rio de Janeiro: relato de caso

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    Visceral leishmaniasis is an anthropozoonosis that is caused by protozoa of the genus Leishmania, especially Leishmania (Leishmania) infantum, and is transmitted to humans by the bite of sandflies of the genus Lutzomyia, such as Lutzomyia longipalpis. There are many reservoirs, including Canis familiaris. It is a chronic infectious disease with systemic involvement that is characterized by three phases: the initial period, the state period and the final period. The main symptoms are fever, malnutrition, hepatosplenomegaly, and pancytopenia. This article reports a case of a patient diagnosed with visceral leishmaniasis in the final period following autochthonous transmission in the urban area of Rio de Janeiro. The case reported here is considered by the Municipal Civil Defense and Health Surveillance of Rio de Janeiro to be the first instance of autochthonous visceral leishmaniasis in humans in the urban area of this city. The patient was discharged and is undergoing a follow-up at the outpatient clinic, demonstrating clinical improvement.A leishmaniose visceral √© uma antropozoonose causada por protozo√°rios do g√™nero Leishmania, principalmente Leishmania (Leishmania) infantum e transmitida ao homem pela picada do flebotom√≠neo do g√™nero Lutzomyia, destacando-se no Brasil a Lutzomyia longipalpis. Os animais reservat√≥rios s√£o muitos, tendo o c√£o dom√©stico (Canis familiaris) como principal reservat√≥rio. Trata-se de uma doen√ßa infecciosa cr√īnica, de envolvimento sist√™mico e caracterizado por tr√™s fases: per√≠odo inicial, per√≠odo de estado e per√≠odo final. As principais manifesta√ß√Ķes s√£o febre, hepatoesplenomegalia, desnutri√ß√£o e pancitopenia. Este artigo tem como objetivo relatar o caso de paciente diagnosticada com leishmaniose visceral em per√≠odo final, de transmiss√£o aut√≥ctone na √°rea urbana da cidade do Rio de Janeiro. O caso relatado neste artigo √© considerado, ap√≥s investiga√ß√£o, pela Secretaria Municipal de Sa√ļde e Defesa Civil do Rio de Janeiro como o primeiro caso aut√≥ctone de leishmaniose visceral em humanos na √°rea urbana da cidade do Rio de Janeiro. O tratamento oferecido foi eficaz e a paciente encontra-se em acompanhamento ambulatorial
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