81 research outputs found

    Informality and social protection : preliminary results from pilot surveys in Bulgaria and Colombia.

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    There is a wide agreement on the fact that a large informal economy leaves many individuals without social protection and reduces government's tax revenue and social security contributions. However, it remains an open question what really drives informality, namely whether workers are simply trapped out of the formal sector or, at least some of them, choose it because it offers better alternatives than a formal job. The policy implications are clearly different in the two cases. In order to shed light on this important issue, the authors propose a household survey instrument to assess the links between informality and social protection. It can be implemented either through a stand-alone survey or by adding a specific module to an existing general survey such as the World Bank's Living Standards Measurement Study. After describing the main survey instrument, the study presents the results of two pilot surveys, carried out in Bulgaria and Colombia, to test the effectiveness of the questionnaire and improve its design. After the introduction is presented, the remainder of the paper is organized as follows. Section 2 discusses the design of the basic questionnaire on the informal sector. Since the instrument can be used also as a stand-alone survey, some questions are quite standard both in their content and format: in what follows, the study will focus on the parts that are not. Section 3 describes in detail the pilot surveys and the adaptation of the questionnaire to country-specific issues. Section 4 asks how representative is the sample of the two pilots. Section 5 presents some descriptive results emerging from the two pilots, and Section 6 examines how results differ according to informality status of respondents. Finally, Section 7 offers concluding remarks.,Access to Finance,Labor Markets,Population Policies,Labor Policies

    Parametric and semiparametric estimation of ordered response models with sample selection and individual-specific thresholds

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    This paper provides a set of new Stata commands for parametric and semiparametric estimation of an extended version of ordered response models that accounts for both sample selection problems and heterogeneity in the thresholds for the latent variable. The standard estimator of ordered response models is therefore generalized along three directions. First, we account for the presence of endogenous selectivity effects that may lead to inconsistent estimates of the model parameters. Second, we control for both observed and unobserved heterogeneity in response scales by allowing the thresholds to depend on a set of covariates and a random individual effect. Finally, we consider two alternative specifications of the model, one parametric and one semiparametric. In the former, the error terms are assumed to follow a multivariate Gaussian distribution and the model parameters are estimated via maximum likelihood. In the latter, the distribution function of the error terms is instead approximated by following Gallant and Nychka (1997), and the model parameters are estimated via pseudo–maximum likelihood. After discussing identification and estimation issues, we present an empirical application using the second wave of the Survey on Health, Ageing and Retirement in Europe (SHARE). Specifically, we estimate an ordered response model for self-reported health on different domains by accounting for both sample selection bias due to survey nonresponse and reporting bias in the self-assessments of health.

    D376E, A205V and A122S substitutions recently found in A. palmeri confer cross-resistance to ALS-inhibiting herbicides

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    Background: Amaranthus palmeri S. Watson is a serious problem in soybean crops from Argentina. This weed has evolved high level of resistance to (ALS)-inhibiting herbicides mainly due to a target-site mechanism by an altered ALS enzyme. In an A. palmeri population from Totoras with cross-resistance to (ALS)-inhibiting herbicides, six allelic versions of the ALS enzyme were identified.Objective: The aim of this study was to evaluate plants from that resistant population carrying the ALS substitutions A122S, D376E or A205V, which had not been characterized before for this species.Methods: Subpopulations with each substitution were produced by a vegetative cloning procedure or by cross-pollination and dose-response assays and herbicide single-dose tests were performed to evaluate in vivo resistance levels to (ALS)-inhibiting herbicides.Results: Dose-response experiments showed that all the resistant subpopulations survived at the highest doses tested (32 X) for imidazolinones, triazolopyrimidines and sulfonylureas, while the susceptible population was completely controlled at considerably lower doses. Furthermore, an analysis of the novel A122S substitution showed that it provides cross-resistance to five classes of (ALS)-inhibiting herbicides, excluding the entire ALS herbicide group as an effective control tool in weed populations carrying this substitution.Conclusions: The results indicated that D376E, A205V and A122S substitutions found for the first time in A. palmeri confer cross-resistance to the most used chemical families from herbicide group 2. Interestingly, it was confirmed that the A205V substitution conferred resistance to herbicides in the triazolopyrimidines family. Data generated should be considered in management strategies for delaying the spread of resistance.Fil: Palmieri, Valeria Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Larran, Alvaro Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Martinatto, Andrea Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Permingeat, Hugo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Perotti, Valeria Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentin

    N of 1, two contemporary arm, randomised controlled clinical trial for bilateral epicondylitis: a new study design

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    Objective To investigate the use of a novel study design in analysis of bilateral elbow pain

    Secretomas fúngicos como pretratamiento biológico sobre biomasa lignocelulósica de panicum prionitis

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    Debido a la inminente necesidad de producir y utilizar fuentes de energía renovables, ciertos pastizales naturales como Panicum prionitis, ricos en polisacáridos y con baja eficiencia forrajera, representan una fuente de azúcares fermentables muy interesante para la producción de bioetanol de segunda generación. Sin embargo, la presencia de lignina en sus hojas hace que el proceso de producción requiera de un pretratamiento previo a la sacarificación. Los hongos de la podredumbre blanca de la madera son capaces de degradar los materiales lignocelulósicos, secretando al medio extracelular diversas enzimas involucradas en tal proceso. En base a este criterio, se evaluó la eficiencia de los secretomas de dos especies fúngicas (Pycnoporus sanguineus y Ganoderma applanatum) como agentes de pretratamiento sobre la biomasa de P. prionitis. Los resultados demuestran que el pretratamiento con secretomas fúngicos resulta más eficiente que los tradicionales (pretratamiento químico y con enzimas ligninolíticas comerciales), permitiendo hidrolizar hasta un 47,5% de la celulosa en el caso de G. applanatum. Ensayos de cromatografía líquida acoplada a espectrometría de masas permitieron la identificación de una gran cantidad de proteínas en los secretomas, revelando que el 34% y el 42% de ellas se encuentran involucradas en los procesos de degradación de la biomasa lignocelulósica para G. applanatum y P. sanguineus, respectivamenteFil: Gauna, Albertina . Universidad Nacional de RosarioFil: Feldman, Susana R.. Universidad Nacional de RosarioFil: Larran, Alvaro S.. Universidad Nacional de RosarioFil: Permingeat, Hugo R.. Universidad Nacional de RosarioFil: Perotti, Valeria E.. Universidad Nacional de Rosari

    Standardization of body composition status in patients with advanced urothelial tumors: the role of a CT-based aI-powered software for the assessment of sarcopenia and patient outcome correlation

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    Background: Sarcopenia is a well know prognostic factor in oncology, influencing patients' quality of life and survival. We aimed to investigate the role of sarcopenia, assessed by a Computed Tomography (CT)-based artificial intelligence (AI)-powered-software, as a predictor of objective clinical benefit in advanced urothelial tumors and its correlations with oncological outcomes. Methods: We retrospectively searched patients with advanced urothelial tumors, treated with systemic platinum-based chemotherapy and an available total body CT, performed before and after therapy. An AI-powered software was applied to CT to obtain the Skeletal Muscle Index (SMI-L3), derived from the area of the psoas, long spine, and abdominal muscles, at the level of L3 on CT axial images. Logistic and Cox-regression modeling was implemented to explore the association of sarcopenic status and anthropometric features to the clinical benefit rate and survival endpoints. Results: 97 patients were included, 66 with bladder cancer and 31 with upper-tract urothelial carcinoma. Clinical benefit outcomes showed a linear positive association with all the observed body composition variables variations. The chances of not experiencing disease progression were positively associated with ∆_SMI-L3, ∆_psoas, and ∆_long spine muscle when they ranged from ~10-20% up to ~45-55%. Greater survival chances were matched by patients achieving a wider ∆_SMI-L3, ∆_abdominal and ∆_long spine muscle. Conclusions: A CT-based AI-powered software body composition and sarcopenia analysis provide prognostic assessments for objective clinical benefits and oncological outcomes
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