Employment Protection, International Specialization, and Innovation

We develop a model to analyse the implications of firing costs on incentives for R&D and international specialization. The Key idea is paying the firing cost, the country with a rigid labor market will tend to produce relatively secure goods, at a late stage of their product life cycle. Under international trade, an international product cycle emerges where, roughly, new goods are first produced in the low firing cost country will specialize in 'secondary innovations', that is, improvements in existing goods, while the low firing cost country will more specialize in 'primary innovation', that is, invention of new goods.

Érosion des sols au Cap Vert : étude des processus et quantification à l’échelle de trois bassins versants de l’île de Santiago

Erosão dos solos em Cabo Verde: estudo dos processos e quantificação à escala de três bacias hidrográficas O arquipélago de Cabo Verde é constituído por 10 ilhas vulcânicas pertence à zona do Sahel que se estende do Atlântico ao Mar Vermelho. Desde então, várias décadas, Cabo Verde é afectado pela desertificação causada principalmente pela recessão climatica e a erosão do solo. Esses fatores, aliados à alta pressão humana sobre os recursos, a topografia acidentada e chuvas tropicais por vezes torrenciais, causam sérios danos aos solos. No entanto, desde sua independência em 1975, o Governo realizou um amplo programa de arborização, recuperação de áreas degradadas e a correcção dos leitos das ribeiras. No entanto, a investigação, muito pouco foi realizada para avaliar as acções de protecção e conservação do solo e da água. Portanto, não há dados sobre o problema da degradação das terras nem balanços. Como parte deste trabalho, foram estudados vários factores que controlam a erosão do solo pela água. Especificamente, buscou-se diferenciar os efeitos das actividades humanas, incluindo a agricultura, os factores climáticos, como chuva e geração de escoamento. Também estabeleceu os primeiros balanços das exportações de matérias em suspensão e em solução no contexto do arquipélago de Cabo Verde. O estudo foi realizado em três bacias hidrográficas da ilha de Santiago, Cabo Verde. Estas três bacias hidrográficas (Longueira, Grande e Godim) estão localizadas na parte central da ilha de Santiago e representam os diversos tipos de uso da terra e as diferentes zonas bioclimaticas da ilha. Existe um gradiente climático entre as três bacias hidrográficas. Na verdade, Longueira que abrange uma área de 4,18 km2, tem um declive médio de 47 %, uma zona florestada de 69% e uma área agrícola de 17 %. Grande com uma área de 1,87 km2, é localizada numa zona sub humida com um declive médio de 50%, é essencialmente agrícola. Godim, com uma área de 2,0 km2, é localizado numa zona semi-árida com um declive médio de 32%, é particularmente uma zona agricola. Para estes três bacias hidrográficas, as cheias foram medidas e amostradas de 2004 a 2009. A bacia de Longueira teve um maior acompanhamento, nomeadamente em termos de amostragem e monitoramento dos escoamentos. Em cada amostra foram feitas a determinação da concentração de matérias em suspensão e a análise dos principais elementos quimicos. Os resultados mostram que a erosão mecânica nas três bacias hidrográficas é caracterizada por uma forte variabilidade espacial e temporal. Durante o período de 2005-2009, o balanço anual média para as bacias hidrográficas de Longueira, Grande e Godim é: 4266, 157 e 10,1 t.km2.an-1, respectivamente. A estação das chuvas de 2006 foi a mais erosiva para as três bacias, particularmente em Longueira, com 2 cheias excepcionais, que têm gerado uma concentração média de sólidos em suspensão superior a 100 g / l. Porém, as estações do ano de 2005 e 2008 foram de uma forma geral menos erosivas porque as concentrações médias não inferiores a 20 g / l. Além disso, não houve cheias para as temporadas 2005 e 2007 para a bacia do Godim. Na bacia de Longueira, o estudo dos fenómenos de histerese na caracterização das cheias mostrou que a evolução temporal das exportações de sólidos em suspensão durante a temporada é fortemente influenciada pelas atividades agrícolas. Na verdade, a primeira cheia causou uma exportação maciça de sedimento disponível e localizado no leito da ribeira. Assim, a segunda cheia exportou menos sedimentos. Um mês após as primeiras chuvas, a prática da monda que reduz a densidade da cobertura vegetal e destructura a camada superficial do solo, gerou uma grande quantidade de sedimento que novamente permitiu uma exportação muito forte de sedimentos durante a terceira forte cheia. Os resultados da erosão química na bacia de Longueira indicam que a taxa de erosão é de 45 t.km2.an-1 com uma forte variabilidade temporal. Na verdade, as temporadas de 2006 e 2007 são as mais erosivas, enquanto 2005 teve uma exportação de matérias disolvidas baixa. A utilização do modelo EMMA (End- Members Mixing Analysis) mostra que os escoamentos hipodermico e profundo, alimentandos os fluxos de elementos dissolvidos são os principais factores da erosão química. É mostrado que esses fluxos causam mais de 90% dos fluxos de erosão química. O escoamento superficial, que contribui com cerca de 70% na formação das cheias, é o maior factor da erosão mecânica do solo.

Globalization and risk sharing

We study the effects of globalization on risk sharing and welfare. Like previous literature, weassume that countries cannot commit to repay their debts. Unlike previous literature, we assumethat countries cannot discriminate between domestic and foreign creditors when repaying theirdebts. This creates novel interactions between domestic and international trade in assets. (i)Increases in domestic trade raise the bene.ts of enforcement and facilitate international trade.In fact, in our setup countries can obtain international risk sharing even in the absence of defaultpenalties. (ii) Increases in foreign trade .i.e. globalization.raise the costs of enforcement andhamper domestic trade. As a result, globalization may worsen domestic risk sharing and lowerwelfare. We show how these e¤ects depend on various characteristics of tradable goods andexplore the roles of borrowing limits, debt renegotiations, and trade policy.

Costly search and design

Firms compete by choosing both a price and a design from a family of designs thatcan be represented as demand rotations. Consumers engage in costly sequential searchamong firms. Each time a consumer pays a search cost he observes a new offering. Anoffering consists of a price quote and a new good, where goods might vary in the extentto which they are good matches for the consumer. In equilibrium, only two design-styles arise: either the most niche where consumers are likely to either love or loathethe product, or the broadest where consumers are likely to have similar valuations. Inequilibrium, different firms may simultaneously offer both design-styles. We performcomparative statics on the equilibrium and show that a fall in search costs can lead tohigher industry prices and profits and lower consumer surplus. Our analysis is relatedto discussions of how the internet has led to the prevalence of niche goods and the"long tail" phenomenon.

Trade credit: Suppliers as debt collectors and insurance providers

There are two fundamental puzzles about trade credit: why does it appearto be so expensive,and why do input suppliers engage in the business oflending money? This paper addresses and answers both questions analysingthe interaction between the financial and the industrial aspects of thesupplier-customer relationship. It examines how, in a context of limitedenforceability of contracts, suppliers may have a comparative advantageover banks in lending to their customers because they hold the extrathreat of stopping the supply of intermediate goods. Suppliers may alsoact as lenders of last resort, providing insurance against liquidityshocks that may endanger the survival of their customers. The relativelyhigh implicit interest rates of trade credit result from the existenceof default and insurance premia. The implications of the model areexamined empirically using parametric and nonparametric techniques on apanel of UK firms.

Erosão dos solos em Cabo Verde - Estudos dos Processos e Quantificação de Três Bacias na Ilha de Santiago

L’archipel du Cap Vert constitué de 10 îles volcaniques appartient à la zone sahélienne qui s’étend de l’atlantique jusqu’à la mer rouge. Depuis, plusieurs décennies le Cap Vert est affecté par la désertification causée en grande partie par la récession climatique et l’érosion des sols. Ces facteurs, associés à la forte pression anthropique sur les ressources, à l’orographie accidentée et à des pluies tropicales parfois diluviennes, provoquent de sérieuses pertes du patrimoine foncier. Cependant, depuis son Indépendance en 1975, le Gouvernement a mené un vaste programme d’arborisation, de restauration des terres et d’aménagement des cours d’eau. Pourtant, très peu de recherches ont été menées pour évaluer les actions de protection et de conservation des sols et des eaux. Par conséquent, il n’existe quasiment pas de données sur la problématique de la dégradation des terres ni de bilans. Dans le cadre de ce travail, nous avons étudié les différents facteurs qui contrôlent l’érosion hydrique des sols. Nous avons plus particulièrement cherché à différencier les effets des activités humaines, notamment agricoles, de ceux des facteurs climatiques comme les précipitations et la génération des écoulements. Nous avons également établi les premiers bilans d’exportations de matières en suspension et en solution dans le contexte de l’archipel du Cap Vert. L’étude a été menée à l’échelle de trois bassins versants de l’ile de Santiago Cap-Vert. Ces trois bassins versant (Longueira, Grande et Godim) sont localisés dans la partie centrale de l’île de Santiago et représentatifs des divers modes d’occupation du sol et des différents climats de l’île. Il existe un gradient climatique entre les trois bassins versants. En effet, Longueira qui présente une superficie de 4,18 km2, une pente moyenne de 47 %, se localise dans une zone humide couverte à 69 % par une forêt et une surface agricole de 17 %. Grande avec une superficie de 1,87 km2, se localise en zone sub humide pour une pente moyenne de 50 %, il est essentiellement agricole. Godim, avec une superficie de 2,0 km2, se localise en zone semi aride, il est particulièrement agricole et sa pente moyenne est de 32 %. Pour ces trois bassins versants, les écoulements de crue à l’exutoire ont été mesurés et échantillonnés de 2004 à 2009. Le bassin versant de Longueira a fait l’objet d’un suivi plus poussé, notamment en termes de fréquence d’échantillonnage et de suivi des écoulements hors crue. Sur chaque échantillon nous avons procédé à la détermination de la concentration des matières en suspension ainsi qu’à l’analyse des éléments majeurs. Les résultats obtenus montrent que l’érosion mécanique dans les 3 bassins versants est caractérisée par une forte variabilité spatiale et temporelle. Sur la période 2005-2009, le bilan moyen annuel pour les bassins versants de Longueira, Grande et Godim est de : 4266, 157 et 10,1 t.km2.an-1 respectivement. La saison humide 2006 a été la plus érosive pour l’ensemble des trois bassins versants et particulièrement dans Longueira avec 2 crues exceptionnelles qui ont généré une concentration moyenne de matières en suspension supérieure à 100 g/l. En revanche, les saisons 2005 et 2008 ont été dans l’ensemble peu érosives car les concentrations moyennes ne dépassèrent pas 20 g/l. Par ailleurs, il n’y a pas eu de lames d’eau écoulées pour les saisons 2005 et 2007 pour le bassin de Godim. Sur le bassin de Longueira, l’étude des phénomènes d’hystérésis permet de caractériser chaque crue et de montrer que l’évolution temporelle des exportations de matières en suspension au cours de la saison est fortement influencée par les activités agricoles. En effet, la première crue provoque l’exportation massive des sédiments disponibles et localisés dans le lit du cours d’eau. En conséquence, la seconde est moins exportatrice de sédiments. Un mois après les premières pluies, les activités de sarclage diminuent la densité du couvert végétal et destructurent la partie superficielle des sols, ce qui provoque à nouveau une très forte exportation de sédiments lors de la troisième crue. Les résultats de l’érosion chimique sur le bassin de Longueira indiquent que le taux d’érosion chimique moyen s’élève à 45 t.km2.an-1 avec une forte variabilité temporelle. En effet, les saisons les plus humides de 2006 et 2007 sont les plus exportatrices de matières en solution, alors que 2005 a eu une faible exportation. L’utilisation du modèle de mélanges EMMA (End-Members Mixing Analysis) montre que les écoulements hypodermique et profond, qui alimentent le cours d’eau en éléments dissous, sont les principaux facteurs de l’érosion chimique. On montre ainsi que les écoulements hors crue sont à l’origine de plus de 90% des flux d’érosion chimique. L’écoulement superficiel, qui contribue à environ 70 % du débit du cours d’eau en crue, constitue un facteur de premier plan de l’érosion mécanique des sols.

Employment protection, international specialization and innovation

We develop a model to analyse the implications of firing costs on incentivesfor R&D and international specialization. The Key idea is paying the firingcost, the country with a rigid labor market will tend to produce relativelysecure goods, at a late stage of their product life cycle.Under international trade, an international product cycle emerges where,roughly, new goods are first produced in the low firing cost country willspecialize in 'secondary innovations', that is, improvements in existinggoods, while the low firing cost country will more specialize in 'primaryinnovation', that is, invention of new goods.

OpenFluDB, a database for human and animal influenza virus.

Although research on influenza lasted for more than 100 years, it is still one of the most prominent diseases causing half a million human deaths every year. With the recent observation of new highly pathogenic H5N1 and H7N7 strains, and the appearance of the influenza pandemic caused by the H1N1 swine-like lineage, a collaborative effort to share observations on the evolution of this virus in both animals and humans has been established. The OpenFlu database (OpenFluDB) is a part of this collaborative effort. It contains genomic and protein sequences, as well as epidemiological data from more than 27,000 isolates. The isolate annotations include virus type, host, geographical location and experimentally tested antiviral resistance. Putative enhanced pathogenicity as well as human adaptation propensity are computed from protein sequences. Each virus isolate can be associated with the laboratories that collected, sequenced and submitted it. Several analysis tools including multiple sequence alignment, phylogenetic analysis and sequence similarity maps enable rapid and efficient mining. The contents of OpenFluDB are supplied by direct user submission, as well as by a daily automatic procedure importing data from public repositories. Additionally, a simple mechanism facilitates the export of OpenFluDB records to GenBank. This resource has been successfully used to rapidly and widely distribute the sequences collected during the recent human swine flu outbreak and also as an exchange platform during the vaccine selection procedure. Database URL: http://openflu.vital-it.ch.

Discounting Arduousness

[cat] Hi ha una literatura creixent que considera desviacions del descompte exponencial estàndar. En aquest article combinem preferències temporalment inconsistents (descompte no constant) amb preferències recursives. Aquest formalisme l’apliquem a les propietats relatives a la demanda del que anomenem bens ardus. La justificació del descompte no estàndar proposat ve donada pel fet que la producció i el consum no són separables per a aquest tipus de bens. L’esforç implica que els individus descompten el consum d’aquests bens d’una manera especial, amb la presència de preferències esbiaixades i d’un ajustament recursiu dinàmic. D’aquesta manera, la voluntat de realitzar un esforç, caracteritzada per un factor de descompte, resulta endògena.

Nutrient relations during an eucalyptus cycle at different population densities

To synchronize nutrient availability with the requirements of eucalyptus during a cultivation cycle, the nutrient flow of this system must be well understood. Essential, for example, is information about nutrient dynamics in eucalyptus plantations throughout a cultivation cycle, as well as impacts on soil nutrient reserves caused by the accumulation and subsequent export of nutrients via biomass. It is also important to quantify the effect of some management practices, such as tree population density (PD) on these fluxes. Some nutrient relations in an experiment with Eucalyptus grandis, grown at different PDs in Santa Barbara, state of Minas Gerais, Brazil, were evaluated for one cultivation cycle. At forest ages of 0.25, 2.5, 4.5, and 6.75 years, evaluations were carried out in the stands at seven different PDs (between 500 and 5,000 trees ha-1) which consisted in chemical analyses of plant tissue sampled from components of the aboveground parts of the tree, from the forest floor and the litterfall. Nutrient contents and allocations of the different biomass components were estimated. In general, there were only small and statistically insignificant effects of PD on the nutrient concentration in trees. With increasing forest age, P, K, Ca and Mg concentrations were reduced in the aboveground components and the forest floor. The magnitud of biochemical nutrient cycling followed the sequence: P > K > N > Mg. At the end of the cycle, the quantities of N, P, Ca and Mg immobilized in the forest floor were higher than in the other components.

Nitrogen balance in soil under eucalyptus plantations

An understanding of the role of organic nitrogen (N) pools in the N supply of eucalyptus plantations is essential for the development of strategies that maximize the efficient use of N for this crop. This study aimed to evaluate the distribution of organic N pools in different compartments of the soil-plant system and their contributions to the N supply in eucalyptus plantations at different ages (1, 3, 5, and 13 years). Three models were used to estimate the contributions of organic pools: Model I considered N pools contained in the litterfall, N pools in the soil microbial biomass and available soil N (mineral N); Model II considered the N pools in the soil, potentially mineralizable N and the export of N through wood harvesting; and Model III (N balance) was defined as the difference between the initial soil N pool (0-10 cm) and the export of N, taking the application of N fertilizer into account. Model I showed that N pools could supply 27 - 70 % of the N demands of eucalyptus trees at different ages. Model II suggested that the soil N pool may be sufficient for 4 - 5 rotations of 5 years. According to the N balance, these N pools would be sufficient to meet the N demands of eucalyptus for more than 15 rotations of 5 years. The organic pools contribute with different levels of N and together are sufficient to meet the N demands of eucalyptus for several rotations.

NUTRIENT DEMAND BY THE CARROT CROP IS INFLUENCED BY THE CULTIVAR

Farmers must carefully choose the cultivar to be grown for a successful carrot crop. The yield potential of the cultivar may influence nutrient demand and should be known to plan for fertilization application. The aim of this study was to evaluate the cultivar effect on carrot yield and on the nutrient content and quantities allocated to leaves and roots. Three experiments were set up in two crop seasons in Rio Paranaíba, MG, Brazil. In the first season, typical summer, 10 summer cultivars were sown. In the second season, summer-winter (transition), two experiments were set up, one with summer cultivars and the other with winter cultivars. The treatments consisted of the carrot cultivars distributed in randomized blocks with four replications. Fresh and dry matter of the roots and leaves was quantified. Yield was calculated based on fresh matter of the roots. The nutrient content in leaves and roots was determined at the time of harvest. These contents and the dry matter production of roots and leaves were used to calculate nutrient uptake and export. The greatest average for total and commercial yield occurred in the crop under summer conditions. Extraction of N and K for most of the cultivars in the three experiments went beyond the amounts applied through fertilizers. Thus, there was contribution of nutrients from the soil to obtain the yields observed. However, the amount of P taken up was considerably less than that applied. This implies that soil P fertility will increase after cropping. The crop season and the cultivars influenced yield, nutrient content in the leaves and roots, and extraction and export of nutrients by the carrot crop.

Discounting Arduousness

[cat] Hi ha una literatura creixent que considera desviacions del descompte exponencial estàndar. En aquest article combinem preferències temporalment inconsistents (descompte no constant) amb preferències recursives. Aquest formalisme l’apliquem a les propietats relatives a la demanda del que anomenem bens ardus. La justificació del descompte no estàndar proposat ve donada pel fet que la producció i el consum no són separables per a aquest tipus de bens. L’esforç implica que els individus descompten el consum d’aquests bens d’una manera especial, amb la presència de preferències esbiaixades i d’un ajustament recursiu dinàmic. D’aquesta manera, la voluntat de realitzar un esforç, caracteritzada per un factor de descompte, resulta endògena.

Critical Mobilities

The field of mobility studies examines social phenomena through the lens of movement. In this perspective, societies are regarded as being constantly reconfigured as they are shaped by a series of mobile entities (capital, people, information). This book engages critically with many of the claims and challenges of mobility studies by providing empirically rich reports of mobilities and their limitations. Instead of assuming a seamless world of flows, the volume foregrounds questions of power, inequality, and moorings as integral to the movement of capital, goods, images, practices, or people. It brings together the work of several internationally renowned scholars, who engage with these movements at critical sites. This is the first book to provide a critical and interdisciplinary view of mobilities covering a broad range of issues rather than a single domain. The chapters deal with current and important issues, such as organ transplants, illegal migrations, urban globalization, international policies of higher education institutions, and scientific diasporas. As a whole, the book provides new insights into how power relations shape mobilities and societies.

Anàlisi econòmica i financera dels sectors de béns de consum i serveis de consum de la Borsa de Madrid

Aquest treball consisteix en una anàlisi econòmica i financera dels sectors de béns de consum i serveis de consum de la Borsa de Madrid en el període 2007-2011. Aquest consisteix en realitzar un estudi dels diferents comptes anuals consolidats de les diferents empreses que configuren cadascun dels sectors mitjançant diferents instruments financers, amb l’objectiu de saber si la crisi econòmica i financera actual ha afectat o no aquests.