881 resultados para Modest


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In this chapter we portray the effects of female education and professional achievement on fertility decline in Spain over the period 1920-1980 (birth cohorts of 1901-1950).A longitudinal econometric approach is used to test the hypothesis that the effects of women’s education in the revaluing of their time had a very significant influence on fertility decline. Although in the historical context presented here improvements in schooling were on a modest scale, they were continuous (with the interruption of the Civil War) and had a significant impact in shaping a model of low fertility in Spain. We also stress the relevance of this result in a context such as the Spanish for which liberal values were absent, fertility control practices were forbidden, and labour force participation of women was politically and socially constrained.

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SUMMARY : The present work addresses several aspects of cell cycle regulation, cell fate specification and cell death in the central nervous system (CNS), specifically the cortex and the retina. More precisely, we investigated the role of Bmi1, a polycomb family gene required for stem cell proliferation and self-renewal, in the development of the cerebral cortex, as well as in the genesis of the retina. These data, together with studies published during the last two decades concerning cell cycle re-activation in apoptotic neurons in the CNS, raised the question of a possible link between regulation of the cell cycle during development and during retinal degeneration. 1. The effects of Bmi1 loss in the cerebral cortex : Consistently with our and others' observations on failure of Bmi9-/- stem cells to proliferate and self-renew in vitro, the Bmi9-/- cerebral cortex presented slight defects in proliferation in stem/progenitor cells compartments in vivo. This was in accordance with the pattern of Bmi1 expression in the developing forebrain. The modest proliferation defects, compared to the drastic consequences of Bmi9 loss in vitro, suggest that cell-extrinsic mechanisms may partially compensate for Bmi1 deletion in vivo during cortical histogenesis. Nevertheless, we observed a decreased proliferating activity in neurogenic regions of the adult telencephalon, more precisely in the subventricular zone, showing that Bmi1 controls neural stem/progenitor proliferation during adulthood in vivo. Our data also highlight an increased production of astrocytes at birth, and a generalized gliosis in the adult Bmi9-/- brain. Importantly, glial progenitors and astrocytes retained the ability to proliferate in the absence of Bmi1. 2. The effects of Bmi1 loss in the retina : The pattern of expression of Bmi1 during development and in the adult retina suggests a role for Bmi1 in cell fate specification and differentiation rather than in proliferation. While the layering and the global structure of the retina appear normal in Bmi1 /adult mice, immunohistochemìcal analysis revealed defects in the three major classes of retinal interneurons, namely: horizontal, bipolar and amacrine cells. Electroretinogram recordings in Bmi9-/- mice are coherent with the defects observed at the histological level, with a reduced b-wave and low-profile oscillatory potentials. These results show that Bmi1 controls not only proliferation, but also cell type generation, as previously observed in the cerebellum. 3. Cell cycle events and related neuroprotective strategies in retinal degeneration : In several neurodegenerative disorders, neurons re-express cell cycle proteins such as cyclin dependent kinases (Cdks) prior to apoptosis. Here, we show for the first time that this is also the case during retinal degeneration. Rd1 mice carry a recessive defect (Pdeóbrd/rd) that causes retinal degeneration and serves as a model of retinitis pigmentosa. We found that photoreceptors express Cdk4 and Cdk2, and undergo DNA synthesis prior to cell death. To interfere with the reactivation of Cdk-related pathways, we deleted E2fs or Brni1, which normally allow cell cycle progression. While deleting E2f1 (downstream of Cdk4/6) in Rd1 mice provides only temporary protection, knocking out Bmi1 (upstream of Cdks) leads to an extensive neuroprotective effect, independent of p16ink4a or p19arf, two tumor suppressors regulated by Bmi1. Analysis of Cdks and the DNA repair-related protein Ligase IV showed that Bmi1 acts downstream of DNA repair events and upstream of Cdks in this neurodegenerative mechanism. Expression of Cdks during an acute model of retinal degeneration, light damage-induced photoreceptor death, points to a role for Bmi1 and cell cycle proteins in retinal degeneration. Considering the similarity with the cell cycle-related apoptotic pathway observed in other neurodegenerative diseases, Bmi1 is a possible general target to prevent or delay neuronal death. RESUME : Ce travail aborde plusieurs aspects de la régulation du cycle cellulaire, de la spécification du devenir des cellules et de la mort cellulaire dans le système nerveux centrale (SNC), plus particulièrement dans le cortex cérébral et dans la rétine. Nous nous sommes intéressés au gène Bmi1, appartenant à la famille polycomb et nécessaire à la prolifération et au renouvellement des cellules souches. Nous avons visé à disséquer son rôle dans le développement du cortex et de la rétine. Ces données, ainsi qu'une série de travaux publiés au cours des deux dernières décennies concernant la réactivation du cycle cellulaire dans les neurones en voie d'apoptose dans le SNC, nous ont ensuite poussé à chercher un lien entre la régulation du cycle cellulaire pendant le développement et au cours de la dégénérescence rétinienne. 1. Les effets de l'inactivation de Bmi1 dans le cortex cérébral : En accord avec l'incapacité des cellules souches neurales in vitro à proliférer et à se renouveler en absence de Bmi1, le cortex cérébral des souris Bmi1-/- présente de légers défauts de prolifération dans les compartiments contenant les cellules souches neurales. Ceci est en accord avec le profil d'expression de Bmi1 dans le télencéphale. Les conséquences de la délétion de Bmi1 sont toutefois nettement moins prononcées in vivo qu'in vitro ; cette différence suggère l'existence de mécanismes pouvant partiellement compenser l'absence de Bmi1 pendant la corticogenèse. Néanmoins, l'observation d'une réduction de la prolifération dans la zone sous-ventriculaire, la zone majeure de neurogenèse dans le télencéphale adulte, montre que Bmi1 contrôle la prolifération des cellules souche/progénitrices neurales chez la souris adulte. Nos résultats démontrent par ailleurs une augmentation de la production d'astrocytes à la naissance ainsi qu'une gliose généralisée à l'état adulte chez les souris Bmi1-/-. Les progéniteurs gliaux et les astrocytes conservent donc leur capacité à proliférer en absence de Bmi1. 2. Les effets de l'inactivation de Bmi1 dans la rétine : Le profil d'expression de Bmi1 pendant fe développement ainsi que dans la rétine adulte suggère un rôle de Bmi1 dans la spécification de certains types cellulaires et dans la différentiation plutôt que dans la prolifération. Alors que la structure et la lamination de la rétine semblent normales chez les souris Bmi1-/-, l'analyse par immunohistochimie amis en évidence des défauts au niveau des trois classes d'interneurones rétiniens (les cellules horizontales, bipolaires et amacrines). Les électrorétinogrammes des souris Bmi1-/- sont cohérents avec les défauts observés au niveau histologique et montrent une réduction de l'onde « b » et des potentiels oscillatoires. Ces résultats montrent que Bmi1 contrôle la génération de certaines sous-populations de neurones, comme démontré auparavant au niveau de cervelet. 3. Réactivation du cycle cellulaire et stratégies théraoeutiaues dans les dégénérescences rétiniennes : Dans plusieurs maladies neurodégénératives, les neurones ré-expriment des protéines du cycle cellulaire telles que les kinases cycline-dépendantes (Cdk) avant d'entrer en apoptose. Nous avons démontré que c'est aussi le cas dans les dégénérescences rétiniennes. Les souris Rd1 portent une mutation récessive (Pde6brd/rd) qui induit une dégénérescence de la rétine et sont utilisées comme modèle animal de rétinite pigmentaire. Nous avons observé que les photorécepteurs expriment Cdk4 et Cdk2, et entament une synthèse d'ADN avant de mourir par apoptose. Pour interférer avec la réactivation les mécanismes Cdk-dépendants, nous avons inactivé les gènes E2f et Bmi1, qui permettent normalement la progression du cycle cellulaire. Nous avons mis en évidence que la délétion de E2f1 (en aval de Cdk4/6) dans les souris Rd1 permet une protection transitoire des photorécepteurs. Toutefois, l'inactivation de Bmi1 (en amont des Cdk) est corrélée à une neuroprotection bien plus durable et ceci indépendamment de p16ink4a et p19arf, deux suppresseurs de tumeurs normalement régulés par Bmi1. L'analyse des Cdk et de la ligase IV (une protéine impliquée dans les mécanismes de réparation de l'ADN) a montré que Bmi1 agit en aval des événements de réparation de l'ADN et en amont des Cdk dans la cascade apoptotique dans les photorécepteurs des souris Rd1. Nous avons également observé la présence de Cdk dans un modèle aigu de dégénérescence rétinienne induit par une exposition des animaux à des niveaux toxiques de lumière. Nos résultats suggèrent donc un rôle général de Bmi1 et des protéines du cycle cellulaire dans les dégénérescences de la rétine. Si l'on considère la similarité avec les événements de réactivation du cycle cellulaire observés dans d'autres maladies neurodégénératives, Bmi1 pourrait être une cible thérapeutique générale pour prévenir la mort neuronale.

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Product placement has become more and more common in Finnish television programmes lately. Product placement, as with the whole of the television industry, is strictly regulated and monitored by law. Surreptitious advertising, sponsorship, cooperative partnerships and product placement are often confused with each other. Partially these activities are interpenetrative. Present legislation doesn't recognise product placement, therefore it doesn't have any specific position in law, thus causing problems. Product placement in domestic tv-programmes is still relatively modest. More extensive activity is perceivable at the movies where the restrictions are considerably more liberal. In the United States, product placement is a part of a production's budget. Pressure to increase financing has grouwn in both Finland and Europe. There has been considerable preparation in advance of a new television directive in the European Union which would allow more liberal advertising and product placement as a part of financing tv-programmes. The proposal for a new directive is currently only on its first round so product placement probably won't become better defined in law in the near future. Finnish television producers were interviewed as part of the research for this thesis, in order to clarify product placement position and usage in domestic televion programmes. Surreptitious advertising, sponsorship, different kinds of cooperative partnerships and the need for guidance were also discussed in the course of the themed interviews. Even though product placement does not currently play a significant part in the financing of a production, there are certainly pressures in that direktion. In the field of television, the legal boundaries of product placement are presently being explored in order to assess its position as a part of budgeting and covering expenses.

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Levels of circulating glucose are tightly regulated. To identify new loci influencing glycemic traits, we performed meta-analyses of 21 genome-wide association studies informative for fasting glucose, fasting insulin and indices of beta-cell function (HOMA-B) and insulin resistance (HOMA-IR) in up to 46,186 nondiabetic participants. Follow-up of 25 loci in up to 76,558 additional subjects identified 16 loci associated with fasting glucose and HOMA-B and two loci associated with fasting insulin and HOMA-IR. These include nine loci newly associated with fasting glucose (in or near ADCY5, MADD, ADRA2A, CRY2, FADS1, GLIS3, SLC2A2, PROX1 and C2CD4B) and one influencing fasting insulin and HOMA-IR (near IGF1). We also demonstrated association of ADCY5, PROX1, GCK, GCKR and DGKB-TMEM195 with type 2 diabetes. Within these loci, likely biological candidate genes influence signal transduction, cell proliferation, development, glucose-sensing and circadian regulation. Our results demonstrate that genetic studies of glycemic traits can identify type 2 diabetes risk loci, as well as loci containing gene variants that are associated with a modest elevation in glucose levels but are not associated with overt diabetes.

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Transcriptome analysis is a powerful tool for unveiling the distribution and magnitude of genetic incompatibilities between hybridizing taxa. The nature of such incompatibilities is closely associated with the evolutionary histories of the parental species and may differ across tissues and between the sexes. In eusocial insects, the presence of castes that experience divergent selection regimes may result in additional distinct patterns of caste-specific hybrid incompatibilities. We analysed levels of expression of >14 000 genes in two life stages of each caste in the fire ants Solenopsis invicta and Solenopsis richteri and in their hybrids. We found strong contributions of both developmental stage and caste to gene expression patterns. In contrast, variability in expression was only weakly associated with taxonomic identity, with hybrid scores falling between those of the two parental species. Hybrid incompatibilities were surprisingly modest, with only 32 genes being mis-expressed, indicating low levels of disruption in gene regulation in hybrids; males and workers each mis-expressed at least seven times as many genes as queens. Interestingly, homologues of many of the mis-expressed genes have been implicated in behavioural variation in Drosophila melanogaster. General expression profiles of hybrids consistently were more similar to those of S. richteri than S. invicta, presumably because S. richteri trans-regulatory elements tend to be dominant and/or because there is an overall bias in the genetic composition of the hybrids towards S. richteri. Altogether, our results suggest that selection acting on each caste may contribute differently to interspecific divergence and speciation in this group of ants.

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Financial markets play an important role in an economy performing various functions like mobilizing and pooling savings, producing information about investment opportunities, screening and monitoring investments, implementation of corporate governance, diversification and management of risk. These functions influence saving rates, investment decisions, technological innovation and, therefore, have important implications for welfare. In my PhD dissertation I examine the interplay of financial and product markets by looking at different channels through which financial markets may influence an economy.My dissertation consists of four chapters. The first chapter is a co-authored work with Martin Strieborny, a PhD student from the University of Lausanne. The second chapter is a co-authored work with Melise Jaud, a PhD student from the Paris School of Economics. The third chapter is co-authored with both Melise Jaud and Martin Strieborny. The last chapter of my PhD dissertation is a single author paper.Chapter 1 of my PhD thesis analyzes the effect of financial development on growth of contract intensive industries. These industries intensively use intermediate inputs that neither can be sold on organized exchange, nor are reference-priced (Levchenko, 2007; Nunn, 2007). A typical example of a contract intensive industry would be an industry where an upstream supplier has to make investments in order to customize a product for needs of a downstream buyer. After the investment is made and the product is adjusted, the buyer may refuse to meet a commitment and trigger ex post renegotiation. Since the product is customized to the buyer's needs, the supplier cannot sell the product to a different buyer at the original price. This is referred in the literature as the holdup problem. As a consequence, the individually rational suppliers will underinvest into relationship-specific assets, hurting the downstream firms with negative consequences for aggregate growth. The standard way to mitigate the hold up problem is to write a binding contract and to rely on the legal enforcement by the state. However, even the most effective contract enforcement might fail to protect the supplier in tough times when the buyer lacks a reliable source of external financing. This suggests the potential role of financial intermediaries, banks in particular, in mitigating the incomplete contract problem. First, financial products like letters of credit and letters of guarantee can substantially decrease a risk and transaction costs of parties. Second, a bank loan can serve as a signal about a buyer's true financial situation, an upstream firm will be more willing undertake relationship-specific investment knowing that the business partner is creditworthy and will abstain from myopic behavior (Fama, 1985; von Thadden, 1995). Therefore, a well-developed financial (especially banking) system should disproportionately benefit contract intensive industries.The empirical test confirms this hypothesis. Indeed, contract intensive industries seem to grow faster in countries with a well developed financial system. Furthermore, this effect comes from a more developed banking sector rather than from a deeper stock market. These results are reaffirmed examining the effect of US bank deregulation on the growth of contract intensive industries in different states. Beyond an overall pro-growth effect, the bank deregulation seems to disproportionately benefit the industries requiring relationship-specific investments from their suppliers.Chapter 2 of my PhD focuses on the role of the financial sector in promoting exports of developing countries. In particular, it investigates how credit constraints affect the ability of firms operating in agri-food sectors of developing countries to keep exporting to foreign markets.Trade in high-value agri-food products from developing countries has expanded enormously over the last two decades offering opportunities for development. However, trade in agri-food is governed by a growing array of standards. Sanitary and Phytosanitary standards (SPS) and technical regulations impose additional sunk, fixed and operating costs along the firms' export life. Such costs may be detrimental to firms' survival, "pricing out" producers that cannot comply. The existence of these costs suggests a potential role of credit constraints in shaping the duration of trade relationships on foreign markets. A well-developed financial system provides the funds to exporters necessary to adjust production processes in order to meet quality and quantity requirements in foreign markets and to maintain long-standing trade relationships. The products with higher needs for financing should benefit the most from a well functioning financial system. This differential effect calls for a difference-in-difference approach initially proposed by Rajan and Zingales (1998). As a proxy for demand for financing of agri-food products, the sanitary risk index developed by Jaud et al. (2009) is used. The empirical literature on standards and norms show high costs of compliance, both variable and fixed, for high-value food products (Garcia-Martinez and Poole, 2004; Maskus et al., 2005). The sanitary risk index reflects the propensity of products to fail health and safety controls on the European Union (EU) market. Given the high costs of compliance, the sanitary risk index captures the demand for external financing to comply with such regulations.The prediction is empirically tested examining the export survival of different agri-food products from firms operating in Ghana, Mali, Malawi, Senegal and Tanzania. The results suggest that agri-food products that require more financing to keep up with food safety regulation of the destination market, indeed sustain longer in foreign market, when they are exported from countries with better developed financial markets.Chapter 3 analyzes the link between financial markets and efficiency of resource allocation in an economy. Producing and exporting products inconsistent with a country's factor endowments constitutes a serious misallocation of funds, which undermines competitiveness of the economy and inhibits its long term growth. In this chapter, inefficient exporting patterns are analyzed through the lens of the agency theories from the corporate finance literature. Managers may pursue projects with negative net present values because their perquisites or even their job might depend on them. Exporting activities are particularly prone to this problem. Business related to foreign markets involves both high levels of additional spending and strong incentives for managers to overinvest. Rational managers might have incentives to push for exports that use country's scarce factors which is suboptimal from a social point of view. Export subsidies might further skew the incentives towards inefficient exporting. Management can divert the export subsidies into investments promoting inefficient exporting.Corporate finance literature stresses the disciplining role of outside debt in counteracting the internal pressures to divert such "free cash flow" into unprofitable investments. Managers can lose both their reputation and the control of "their" firm if the unpaid external debt triggers a bankruptcy procedure. The threat of possible failure to satisfy debt service payments pushes the managers toward an efficient use of available resources (Jensen, 1986; Stulz, 1990; Hart and Moore, 1995). The main sources of debt financing in the most countries are banks. The disciplining role of banks might be especially important in the countries suffering from insufficient judicial quality. Banks, in pursuing their rights, rely on comparatively simple legal interventions that can be implemented even by mediocre courts. In addition to their disciplining role, banks can promote efficient exporting patterns in a more direct way by relaxing credit constraints of producers, through screening, identifying and investing in the most profitable investment projects. Therefore, a well-developed domestic financial system, and particular banking system, would help to push a country's exports towards products congruent with its comparative advantage.This prediction is tested looking at the survival of different product categories exported to US market. Products are identified according to the Euclidian distance between their revealed factor intensity and the country's factor endowments. The results suggest that products suffering from a comparative disadvantage (labour-intensive products from capital-abundant countries) survive less on the competitive US market. This pattern is stronger if the exporting country has a well-developed banking system. Thus, a strong banking sector promotes exports consistent with a country comparative advantage.Chapter 4 of my PhD thesis further examines the role of financial markets in fostering efficient resource allocation in an economy. In particular, the allocative efficiency hypothesis is investigated in the context of equity market liberalization.Many empirical studies document a positive and significant effect of financial liberalization on growth (Levchenko et al. 2009; Quinn and Toyoda 2009; Bekaert et al., 2005). However, the decrease in the cost of capital and the associated growth in investment appears rather modest in comparison to the large GDP growth effect (Bekaert and Harvey, 2005; Henry, 2000, 2003). Therefore, financial liberalization may have a positive impact on growth through its effect on the allocation of funds across firms and sectors.Free access to international capital markets allows the largest and most profitable domestic firms to borrow funds in foreign markets (Rajan and Zingales, 2003). As domestic banks loose some of their best clients, they reoptimize their lending practices seeking new clients among small and younger industrial firms. These firms are likely to be more risky than large and established companies. Screening of customers becomes prevalent as the return to screening rises. Banks, ceteris paribus, tend to focus on firms operating in comparative-advantage sectors because they are better risks. Firms in comparative-disadvantage sectors finding it harder to finance their entry into or survival in export markets either exit or refrain from entering export markets. On aggregate, one should therefore expect to see less entry, more exit, and shorter survival on export markets in those sectors after financial liberalization.The paper investigates the effect of financial liberalization on a country's export pattern by comparing the dynamics of entry and exit of different products in a country export portfolio before and after financial liberalization.The results suggest that products that lie far from the country's comparative advantage set tend to disappear relatively faster from the country's export portfolio following the liberalization of financial markets. In other words, financial liberalization tends to rebalance the composition of a country's export portfolio towards the products that intensively use the economy's abundant factors.

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In line with the rights and incentives provided by the Bayh-Dole Act of 1980, U.S. universities have increased their involvement in patenting and licensing activities through their own technology transfer offices. Only a few U.S. universities are obtaining large returns, however, whereas others are continuing with these activities despite negligible or negative returns. We assess the U.S. universities’ potential to generate returns from licensing activities by modeling and estimating quantiles of the distribution of net licensing returns conditional on some of their structural characteristics. We find limited prospects for public universities without a medical school everywhere in their distribution. Other groups of universities (private, and public with a medical school) can expect significant but still fairly modest returns only beyond the 0.9th quantile. These findings call into question the appropriateness of the revenue-generating motive for the aggressive rate of patenting and licensing by U.S. universities.

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In this paper we present a simple theory-based measure of the variations in aggregate economic efficiency: the gap between the marginal product of labor and the household s consumption/leisure tradeoff. We show that this indicator corresponds to the inverse of the markup of price over social marginal cost, and give some evidence in support of this interpretation. We then show that, with some auxilliary assumptions our gap variable may be used to measure the efficiency costs of business fluctuations. We find that the latter costs are modest on average. However, to the extent the flexible price equilibrium is distorted, the gross efficiency losses from recessions and gains from booms may be large. Indeed, we find that the major recessions involved large efficiency losses. These results hold for reasonable parameterizations of the Frisch elasticity of labor supply, the coefficient of relative risk aversion, and steady state distortions.

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Previous studies demonstrated that peroxisome-proliferator-activated receptor (PPAR)-alpha or PPAR-delta activation stimulates keratinocyte differentiation, is anti-inflammatory, and improves barrier homeostasis. Here we demonstrate that treatment of cultured human keratinocytes with ciglitazone, a PPAR-gamma activator, increases involucrin and transglutaminase 1 mRNA levels. Moreover, topical treatment of hairless mice with ciglitazone or troglitazone increases loricrin, involucrin, and filaggrin expression without altering epidermal morphology. These results indicate that PPAR-gamma activation stimulates keratinocyte differentiation. Additionally, PPAR-gamma activators accelerated barrier recovery following acute disruption by either tape stripping or acetone treatment, indicating an improvement in permeability barrier homeostasis. Treatment with PPAR-gamma activators also reduced the cutaneous inflammatory response that is induced by phorbol 12-myristate-13-acetate, a model of irritant contact dermatitis and oxazolone, a model of allergic contact dermatitis. To determine whether the effects of PPAR-gamma activators are mediated by PPAR-gamma, we next examined animals deficient in PPAR-gamma. Mice with a deficiency of PPAR-gamma specifically localized to the epidermis did not display any cutaneous abnormalites on inspection, but on light microscopy there was a modest increase in epidermal thickness associated with an increase in proliferating cell nuclear antigen (PCNA) staining. Key functions of the skin including permeability barrier homeostasis, stratum corneum surface pH, and water-holding capacity, and response to inflammatory stimuli were not altered in PPAR-gamma-deficient epidermis. Although PPAR-gamma activators stimulated loricrin and filaggrin expression in wild-type animals, however, in PPAR-gamma-deficient mice no effect was observed indicating that the stimulation of differentiation by PPAR-gamma activators is mediated by PPAR-gamma. In contrast, PPAR-gamma activators inhibited inflammation in both PPAR-gamma-deficient and wild-type mouse skin, indicating that the inhibition of cutaneous inflammation by these PPAR-gamma activators does not require PPAR-gamma in keratinocytes. These observations suggest that thiazolidindiones and perhaps other PPAR-gamma activators maybe useful in the treatment of cutaneous disorders.

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Temozolomide (Temodal, Temodar), an imidazol derivative, is a second-generation alkylating agent. The orally available prodrug with the capacity of crossing the blood-brain barrier received accelerated US FDA approval in 1999. Three pivotal Phase II trials showed modest activity in the treatment of recurrent anaplastic astrocytoma glioblastoma. In 2005, the FDA and the European Agency for the Evaluation of Medicinal Products approved temozolomide for use in newly diagnosed glioblastoma, in conjunction with radiotherapy, based on an European Organisation for Research and Treatment of Cancer/National Cancer Institute of Canada Phase III trial. The adverse events associated with temozolomide are mild-to-moderate and generally predictable; the most serious are noncumulative and reversible myelosuppression and, in particular, thrombocytopenia, which occurs in less than 5% of patients. Continuous temozolomide administration is associated with profound CD4-selective lymphocytopenia. Molecular studies have suggested that the benefit of temozolomide chemotherapy is restricted to patients whose tumors have a methylated methylguanine methyltransferase gene promotor and are thus unable to repair some of the chemotherapy-induced DNA damage. Temozolomide is under investigation for other disease entities, in particular lower-grade glioma, brain metastases and melanoma.

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Projections of U.S. ethanol production and its impacts on planted acreage, crop prices, livestock production and prices, trade, and retail food costs are presented under the assumption that current tax credits and trade policies are maintained. The projections were made using a multi-product, multi-country deterministic partial equilibrium model. The impacts of higher oil prices, a drought combined with an ethanol mandate, and removal of land from the Conservation Reserve Program (CRP) relative to baseline projections are also presented. The results indicate that expanded U.S. ethanol production will cause long-run crop prices to increase. In response to higher feed costs, livestock farmgate prices will increase enough to cover the feed cost increases. Retail meat, egg, and dairy prices will also increase. If oil prices are permanently $10-per-barrel higher than assumed in the baseline projections, U.S. ethanol will expand significantly. The magnitude of the expansion will depend on the future makeup of the U.S. automobile fleet. If sufficient demand for E-85 from flex-fuel vehicles is available, corn-based ethanol production is projected to increase to over 30 billion gallons per year with the higher oil prices. The direct effect of higher feed costs is that U.S. food prices would increase by a minimum of 1.1% over baseline levels. Results of a model of a 1988-type drought combined with a large mandate for continued ethanol production show sharply higher crop prices, a drop in livestock production, and higher food prices. Corn exports would drop significantly, and feed costs would rise. Wheat feed use would rise sharply. Taking additional land out of the CRP would lower crop prices in the short run. But because long-run corn prices are determined by ethanol prices and not by corn acreage, the long-run impacts on commodity prices and food prices of a smaller CRP are modest. Cellulosic ethanol from switchgrass and biodiesel from soybeans do not become economically viable in the Corn Belt under any of the scenarios. This is so because high energy costs that increase the prices of biodiesel and switchgrass ethanol also increase the price of cornbased ethanol. So long as producers can choose between soybeans for biodiesel, switchgrass for ethanol, and corn for ethanol, they will choose to grow corn. Cellulosic ethanol from corn stover does not enter into any scenario because of the high cost of collecting and transporting corn stover over the large distances required to supply a commercial-sized ethanol facility.

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We study the potential consequences of a hypothetical trade boycott against Catalan products organized by some sectors of the Spanish society mainly for political reasons. A symmetric trade boycott would have two effects: a reduction of Catalan exports to Spain and a partial process of import substitution in Catalonia. In order to quantify the economic impact of the boycott, we compare the "actual" Catalan economy, as described in the input-output table for 2005, with a "simulated" Catalan economy that takes into account the effects of a boycott on the trade exchanges between Catalonia and Spain.

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The development and use of chemotherapy for patients with prostate cancer was slow and modest in comparison with other solid tumor sites. While many cytotoxic agents and multiple drug combinations were tested during the 1980, the first recognized drug for men with metastatic castration-resistant prostate cancer (mCRPC) was mitoxantrone combined with prednisone in 1996. Mitoxantrone showed an improvement in quality of life and pain compared to men treated with prednisone alone. In 2004, two randomized controlled trials found docetaxel superior to mitoxantrone in PSA response and survival. Despite the somewhat higher side effect rate, quality of life and pain were also improved with docetaxel. Unfortunately only about every second man benefits from this treatment and there are no approved criteria to select patients with better chances of response. It takes about 3 months of treatment to identify non-responders and all patients will ultimately progress and most of them will die of prostate cancer. Many men with mCRPC were treated with mitoxantrone after progression on docetaxel without a strong evidence for such a choice. More recently, the benefit of a second-line chemotherapy was addressed within a randomized controlled trial. A new taxane, cabazitaxel, was found superior to mitoxantrone in terms of overall survival despite the previous treatment with docetaxel and therefore recently approved in this indication. The most important challenges and opportunities for future studies will be the combination of chemotherapy with hormonal or non-hormonal targeted agents, the establishment of treatment algorithms to best sequence docetaxel and cabazitaxel and non-cytotoxic agents. Patient selection criteria as well as early biomarkers of response or resistance would also be important for patients and clinicians. Toxicity and quality of life are particular important aspects of drug development in current and future studies which aim to improve treatment options in this frequently elderly patient population.

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This paper presents new estimates of total factor productivity growth in Britain for the period1770 1860. We use the dual technique and argue that the estimates we derive from factorprices are of similar quality to quantity-based calculations. Our results provide further evidence,calculated on the basis of an independent set of sources, that productivity growth duringthe British Industrial Revolution was relatively slow. The Crafts Harley view of theIndustrial Revolution is thus reinforced. Our preferred estimates suggest a modest accelerationafter 1800.

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The epidemiology of skin cancer shows interplay between host susceptibility, (ultraviolet) environment, socioeconomical conditions and behavioural patterns. Its etiology is not yet fully elucidated and reveals intriguing questions. Fair-skinned populations have experienced over the last 60 years a rapid increase in the incidence of melanoma which is unparalleled by any other cancer, although signs of levelling off and stabilization in incidence have recently been observed in some countries. Despite many primary prevention and early detection campaigns over the last decades in Europe, decreases in melanoma mortality are modest and limited to a few countries. Further, reduction in the incidence of thick melanomas has not yet been evidenced. In this presentation, drivers for the incidence and mortality trends of skin cancer, with a strong focus on melanoma, its most lethal form, will be discussed.