1,274 research outputs found
Appropriability mechanisms, innovation, and productivity: evidence from the UK
We use an extended version of the well-established Crepon, Duguet, and Mairesse model [1998. “Research, Innovation and Productivity: An Econometric Analysis at the Firm Level.” Economics of Innovation and New Technology 7 (2): 115–158] to model the relationship between appropriability mechanisms, innovation, and firm-level productivity. We enrich this model in three ways: (1) We compare estimates obtained using a broader definition of innovation spending to those that use R&D spending. (2) We assume that a firm simultaneously innovates and chooses among different appropriability methods to protect the innovation. (3) We estimate the impact of innovation output on firm productivity conditional on the choice of appropriability mechanism. We find that firms that innovate and rate formal methods for the protection of intellectual property highly are more productive than other firms, but that the same does not hold in the case of informal methods of protection, except possibly for large firms as opposed to SMEs. We also find that this result is strongest for firms in the services, trade, and utility sectors, and negative in the manufacturing sector
Oral Contraceptive Use and Clinical Outcomes in Patients with Multiple Sclerosis
Experimental and clinical data suggest a role of sex steroids in the pathogenesis of multiple sclerosis (MS). Scant information is available about the potential effect of oral contraceptive (OC) use on the prognosis of the disease. We aimed to evaluate this. The study population consisted of 132 women with relapsing-remitting MS before receiving disease modifying treatment and a mean disease duration 6.2 (SD 5.1) years. Three groups of patients were distinguished according to their OC behavior: [1] never-users, patients who never used OC [2] past-users, patients who stopped OC use before disease onset, and [3] after-users, those who used these drugs after disease onset. Multiple linear and logistic regression models were used to analyze the association between oral contraceptive use and annualized relapse rates, disability accumulation and severity of the disease. After-user patients had lower Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Severity Score (MSSS) values than never users (p<0.001 and p=0.002, respectively) and past users (p=0.010 and p=0.002, respectively). These patients were also more likely to have a benign disease course (MSSS<2.5) than never and past users together (OR: 4.52, 95%CI: 2.13-9.56, p<0.001). This effect remained significant after adjustment for confounders, including smoking and childbirths (OR: 2.97, 95%CI: 1.24, 6.54, p=0.011 and for MSSS β: -1.04; 95% C.I. -1.78, -0.30, p=0.006). These results suggest that OC use in women with relapsing-remitting MS is possible associated with a milder disabling disease course
Competition and Efficiency: Some theoretical prescription and Empirical evidence for the European dairy industry
This paper analyses the mechanisms through which increasing market competition may help cooperatives to improve technical efficiency to guarantee positive profits. This hypothesis is first formalised in a partial equilibrium framework and then is tested on a sample of European investor owned and cooperative firms, belonging to the dairy industry, using frontier analysis. Technical efficiency indexes are computed by using the one-stage approach as suggested by Reifschneider and Stevenson (1991), where proxies for competition are introduced as determinants of efficiency variancey. The results support the hypothesis that increasing market competition can affect positively the cooperatives\ub4 efficiency.
Depositato come Quaderno del Dipartimento TESAF n. 96.
Disponibile come Working Paper n. 3/2006 del Centro per la Formazione in Economia e Politica dello Sviluppo Rurale al sito: http://www.depa.unina.it/depa/WP_3_2006.pd
Influence of Apolipoprotein E Plasma Levels and Tobacco Smoking on the Induction of Neutralising Antibodies to Interferon-Beta
Interferon-beta (IFN-beta) therapy for multiple sclerosis (MS) is associated with a potential for induction of neutralizing antibodies (NAbs). Because immune reactivity depends on changes in lipoprotein metabolism, we investigated whether plasma lipoprotein profiles could be associated with the development of NAbs. Thirty-one female MS patients treated with subcutaneously administered IFN-beta were included. Demographic and clinical characteristics were compared between NAbs response groups using t tests for continuous and logistic regression analysis and Fisher's exact tests for categorical data, respectively. Multivariate logistic regression was used to evaluate the effect of potential confounders. Patients who developed NAbs had lower apoE levels before treatment, 67 (47-74) mg/L median (interquartile range), and at the moment of NAb analysis, 53 (50-84) mg/L, in comparison to those who remained NAb-negative, 83 (68-107) mg/L, P = 0.03, and 76 (66-87) mg/L, P = 0.04, respectively. When adjusting for age and smoking for a one-standard deviation decrease in apoE levels, a 5.6-fold increase in the odds of becoming NAb-positive was detected: odds ratios (OR) 0.18 (95% CI 0.04-0.77), P = 0.04. When adjusting for apoE, smoking habit became associated with NAb induction: OR 5.6 (95% CI 1.3-87), P = 0.03. These results suggest that apoE-containing lipoprotein metabolism and, possibly, tobacco smoking may be associated with risk of NAb production in female MS patients treated with IFN-beta
Image Compression Techniques by using Wavelet Transform
This paper is concerned with a certain type of compression techniques by using wavelet transforms. Wavelets are used to characterize a complex pattern as a series of simple patterns and coefficients that, when multiplied and summed, reproduce the original pattern. The data compression schemes can be divided into lossless and lossy compression. Lossy compression generally provides much higher compression than lossless compression. Wavelets are a class of functions used to localize a given signal in both space and scaling domains. A MinImage was originally created to test one type of wavelet and the additional functionality was added to Image to support other wavelet types, and the EZW coding algorithm was implemented to achieve better compression. Keywords: Wavelet Transforms, Image Compression, Lossless Compression, Lossy Compressio
Fingolimod Treatment Modulates PPARγ and CD36 Gene Expression in Women with Multiple Sclerosis
Fingolimod is an oral immunomodulatory drug used in the treatment of multiple sclerosis (MS) that may change lipid metabolism. Peroxisome proliferator-activated receptors (PPAR) are transcription factors that regulate lipoprotein metabolism and immune functions and have been implicated in the pathophysiology of MS. CD36 is a scavenger receptor whose transcription is PPAR regulated. The objective of this study was to evaluate whether fingolimod treatment modifies PPAR and CD36 gene expression as part of its action mechanisms. Serum lipoprotein profiles and PPAR and CD36 gene expression levels in peripheral leukocytes were analysed in 17 female MS patients before and at 6 and 12 months after fingolimod treatment initiation. Clinical data during the follow-up period of treatment were obtained. We found that fingolimod treatment increased HDL-Cholesterol and Apolipoprotein E levels and leukocyte PPARγ and CD36 gene expression. No correlations were found between lipid levels and variations in PPARγ and CD36 gene expression. PPARγ and CD36 variations were significantly correlated during therapy and in patients free of relapse and stable disease. Our results suggest that PPARγ and CD36-mediated processes may contribute to the mechanisms of action of fingolimod in MS. Further studies are required to explore the relation of the PPARγ/CD36 pathway to the clinical efficacy of the drug and its involvement in the pathogenesis of the disease.info:eu-repo/semantics/publishedVersio
Phylogenetic and Functional Diversity of Faecal Microbiome of Pack Animals
The present chapter describes the microbial diversity of faecal microbiomes of pack animals. The sequencing data generated through ion semiconductor sequencing technology were analysed using EBI metagenomics and MG‐RAST server tools. Bacteria were the major domain in all the pack animals. At the phylogenetic level, Firmicutes was the major phylum. Clostridiales was the major order. Ruminococcus flavefaciens was the major species in camel, whereas the top‐most species existing in Equidae family was Streptococcus equinus. Among the 28 major functional categories, protein metabolism functionality was dominant in pack animals. The genes associated with protein processing and modification as well as for protein folding are higher in mules and in camel they are lowest. Central carbohydrate metabolism was the major functional group under carbohydrate metabolism in pack animals. Variation in the amino acids and its derivatives was seen in pack animals. Genes associated with proline and 4‐hydroxy prolines were present in Equidae family only. Clustering using ward with Bray‐Curtis distance matrix for the functional categories showed that donkey and mule are most closely related and clustered with the horse metagenome
Apolipoprotein E Polymorphism Interacts with Cigarette Smoking in Progression of Multiple Sclerosis
BACKGROUND AND PURPOSE:
The influence of apolipoprotein E (ApoE) polymorphism on clinical severity of multiple sclerosis (MS) is still controversial. Cigarette smoking has been suggested to influence the progression of disability in these patients. In this study, we aimed to investigate whether an interaction of smoking with the ApoE polymorphism influences the progression of disability in MS patients.
METHODS:
Smoking history from 205 female patients with MS was obtained. Clinical data collected include age at onset, disease duration, annual relapse rate, the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Severity Score (MSSS). ApoE polymorphism was examined in all patients and stratified according to smoking status and associations with the clinical data investigated.
RESULTS:
There were no significant associations between cigarette smoking and any of the clinical characteristics in the whole group of patients. In women carrying the ApoE E4 isoform, smokers had a lower EDSS (P = 0.033) and MSSS (P = 0.023) in comparison with non-smokers.
CONCLUSION:
Our data suggest that in women with MS carrying the ApoE E4 isoform, cigarette smoking may have a protective influence on disease progression and accumulation of disability. These findings need to be confirmed by future large longitudinal studies.info:eu-repo/semantics/publishedVersio
Espaço, Violência e Identidade em Alexandria: um Estudo Sobre o Conflito de 38 d.C.
Nesta dissertação, analisa-se a relação existente entre espaço, violência e identidade cultural durante o conflito ocorrido em 38 d.C. na cidade de Alexandria, capital da província do Egito, que envolveu gregos, egípcios e judeus. Para tanto, o recurso bibliográfico foram as obras In Flaccum e Legatio ad Gaium, de Filo de Alexandria; a obra Contra Apionem, de Flávio Josefo; os Acta Alexandrinorum e a Carta de Cláudio aos Alexandrinos. Alexandria foi construída em 331 a.C. e, no decorrer do domínio ptolomaico, alcançou grande destaque nos campos político, econômico e cultural, o que atraiu um grande número de indivíduos das mais variadas etnias, tornando-a uma cidade multiétnica. Nesse contexto, investigam-se o processo de formação das comunidades grega, egípcia e judaica, as singularidades de cada grupo, as aproximações e a forma como as relações sociais se transformaram após a dominação romana em 30 a.C. O referencial teórico empregado nessa pesquisa pauta-se nos conceitos de estabelecidos, outsiders, conflito, violência, espaço, identidade e diferença. Já a metodologia utilizada é a Análise de Conteúdo. O objetivo principal é compreender como a apropriação dos diversos espaços da cidade e o recurso à violência contribuíram na formação e na afirmação da identidade dos atores sociais envolvidos na revolta
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