1,497 research outputs found
Are estimated peer effects on smoking robust? Evidence from adolescent students in Spain
Adolescent smoking is one of the most pressing public health problems. The objective of this paper is to analyse the influence of peer pressure on adolescent cigarette consumption. More concretely, we explore the significance and robustness of the peer effects using several estimation methods employed in the existing literature. On the basis of the data provided by the 2004 Spanish survey on drug use in the school population, we estimate the probability of being a smoker by two-stage models. The results reveal that when we use standard errors used in the literature the class peer variable appears to be significant. However, the class peer variable is not significant when we calculate more exigent standard errors, a result that is robust across all specifications. The paper suggests the need for a more cautious interpretation of the peer effects found previously in the literature until a deeper analysis confirms the robustness of the peer effects
How to escape poverty through education?: intergenerational evidence in Spain
This article analyses the determinants of escaping poverty through education in Spain, with this being the country that, is among the top European countries regarding the percentage of the population affected by poverty. Specifically, the article studies the transmission of poverty over two generations by analysing the factors that affect the probability of having completed the secondary level of education. To that end, we use the conceptual Quantity–Quality model of Becker–Lewis, empirically estimated by using the Survey of Living Conditions (2011) provided by the Spanish Statistical Institute. Our results confirm the intergenerational transmission of poverty in Spain, in such a way that the probability that the respondent has completed secondary education is determined, although not exclusively, by the family conditions of the respondents during their teenage years
Transformação de coordenadas cartográficas: o exemplo da região de Granja (NW do Ceará, Brasil)
Este estudo tem como principal objetivo mostrar a importância de se efetuar a análise metódica da cartografia de
base que suporta a produção de Cartografia Geológica, antes de iniciar o trabalho de campo. Em certas regiões, as cartas
base publicadas estão ainda associadas a redes geodésicas clássicas, o que obriga a proceder à transformação de coordenadas
para assegurar que todos os dados geo-espaciais são definidos no mesmo sistema de referência espacial. Neste
estudo, selecionaram-se 8 pontos localizados sobre as cartas publicadas na região de Granja (NW do Ceará, Brasil),
determinaram-se as coordenadas no Datum topocêntrico das cartas (CA 70-72) e procedeu-se à sua transformação para
os Data geocêntricos WGS84 e SIRGAS2000. As diferenças entre as coordenadas obtidas nos três sistemas são residuais,
indicando que erros introduzidos quando se desconsideram parâmetros essenciais como o Datum Geodésico são, neste
caso, mínimos para efeitos de Cartografia Geológica.This study draws attention to the importance of conducting a detailed analysis of cartographic products that sustain the Geological Mapping before
starting the field work. In some regions, the published base maps are still related to classical geodetic networks. Therefore, it is fundamental to perform the
adequate coordinate transformation to ensure that all spatial data are defined relatively to the same spatial reference system. This is particularly relevant
when GPS and GIS are used to obtain and plot spatial data. The present study involved the selection of 8 points located on the published maps for the
Granja region (NW Ceará, Brazil), the determination of their coordinates in the CA 70-72 topocentric map Datum and their subsequent transformation
to the geocentric Data WGS84 and SIRGAS2000. The differences between coordinates are residual, indicating that the error introduced when
essential parameters such as the Geodetic Datum are disregarded are, in this case, minimum
Evaluation Of Biochemical And Serological Methods To Identify And Clustering Yeast Cells Of Oral Candida Species By Chromagar Test, Sds-page And Elisa.
The purpose of this work was to evaluate biochemical and serological methods to characterize and identify Candida species from the oral cavity. The strains used were five Candida species previously identified: C. albicans, C. guilliermondii, C. parapsilosis, C. krusei, C. tropicalis, and Kluyveromyces marxianus, as a negative control. The analyses were conducted through the SDS-PAGE associated with statistical analysis using software, chromogenic medium, and CHROMagar Candida (CA), as a differential medium for the isolation and presumptive identification of clinically important yeasts and an enzyme-linked immunoabsorbent assay (ELISA), using antisera produced against antigens from two C. albicans strains. This method enabled the screening of the three Candida species: C. albicans, C. tropicalis, and C. krusei, with 100% of specificity. The ELISA using purified immunoglobulin G showed a high level of cross-reaction against protein extracts of Candida species. The SDS-PAGE method allowed the clustering of species-specific isolates using the Simple Matching coefficient, S(SM) = 1.0. The protein profile analysis by SDS-PAGE increases what is known about the taxonomic relationships among oral yeasts. This methodology showed good reproducibility and allows collection of useful information for numerical analysis on information relevant to clinical application, and epidemiological and systematical studies.64231732
Lethal dose of gamma radiation for eggs of Corcyra cephalonica (Stainton, 1865) (Lepidoptera: Pyralidae), rice moth
O. experimento teve como objetivo observar os efeitos da radiação gama em ovos da traça do arroz, Corcyra cephalonica (STAINTON, 1865). As doses utilizadas no experimento foram; 0; 25; 50; 75; 100; 125; 150; 175; 200 Gy. O experimento foi conduzido em sala climatizada a 25 ± 2°C e 70 ± 10% de umidade relativa. Observou-se que as doses letais DL50 e DL100 para ovos provenientes de adultos criados em dieta artificial foram respectivamente de 16 e 75 Gy.The aim of this experiment was to observe the effects of gamma radiation on rice moth Corcyra cephalonica (STAINTON, 1865) eggs. The doses utilized in this experiment were 0; 25; 50; 75; 100; 125; 150; 175; 200 Gy. The experiment was carried out in a climatic room at 25 ± 2°C and 70 ± 10% R.H. It was observed that lethal dose LD50 and LD100 for eggs from adults reared by artificial diet were 16 and 75 Gy, respectively
Insecticide Reproductive Toxicity Profile: Organophosphate, Carbamate and Pyrethroids
Exposure to pesticides is very common world-wide, and is broadly
known the acute toxic effects to humans of pesticides following a high
dose exposure; however, knowledge about chronic low-dose adverse
effects to specific pesticides is more limited. Reproductive functions
can be affected, with birth defects, impaired fecund ability, infertility
and altered growth. This paper will focus on the deleterious effects
that may appear in the offspring, during early and later stages of life,
after prenatal exposure to insecticides, not only on women with direct
exposure but also on subjects with indirect exposure such as consumers
or residents of rural communities. Prenatal exposure to pesticides could
alter normal fetal development and could threaten future welfare. The
main changes observed in prenatal exposure to organophosphates
are alterations in the central nervous system, in the metabolic and
hormonal system as endocrine disruptor and over the birth outcomes.
Carbamates may cause developmental delay when the applications
of carbamates during pregnancy were nearby the home. Pyrethroids
are among the most frequently used pesticides and account for more
than one-third of the insecticides currently marketed in the world. For
this reason the prenatal exposition used to be for long periods causing
clinical, biochemical and neurological changes
Thermal conditions affecting heat transfer in FDM/FFE: a contribution towards the numerical modelling of the process
The performance of parts produced by Free Form Extrusion (FFE), an increasingly popular additive manufacturing technique, depends mainly on their dimensional accuracy, surface quality and mechanical performance. These attributes are strongly influenced by the evolution of the filament temperature and deformation during deposition and solidification. Consequently, the availability of adequate process modelling software would offer a powerful tool to support efficient process set-up and optimisation. This work examines the contribution to the overall heat transfer of various thermal phenomena developing during the manufacturing sequence, including convection and radiation with the environment, conduction with support and between adjacent filaments, radiation between adjacent filaments and convection with entrapped air. The magnitude of the mechanical deformation is also studied. Once this exercise is completed, it is possible to select the material properties, process variables and thermal phenomena that should be taken in for effective numerical modelling of FFE.This work was supported by Strategic Project - LA 25 - 2013–2014 [PEst-C/CTM/LA0025/2013]
PCN78 Cost-Effectiveness of Plerixafor Plus GCSF for Mobilization of Peripheral Blood Stem Cells in Patients With Myeloma and Lymphoma in Spain
Preservation of sliced cooked ham at 25, 30 and 37°C under moderated pressure (hyperbaric storage) and comparison with refrigerated storage
The feasibility of hyperbaric storage (HS) to substitute refrigeration as a lower energetic cost alternative to refrigeration, for sliced cooked ham preservation was assessed by using temperatures and pressures ranging 25–37◦C and 25–150 MPa for 4 and 8 h.
At microbiological level, storage at 25 ◦C, 30 ◦C, and 37 ◦C, showed no effect on microbial growth at 25 MPa reaching levels similar to atmospheric pressure storage, around 5 log CFU/g for both total aerobic mesophiles (TAM) and lactic acid bacteria (LAB). Nevertheless, the storage at 50 MPa and 30 ◦C resulted in microbial growth inhibition, resulting in TAM and LAB counts similar to refrigeration, of about 3.8 log CFU/g for both the microorganisms.
Additionally, the increase of the storage pressure to 100–150 MPa resulted in microbial inacti-vation, leading to microbial loads of almost 1 log CFU/g lower than refrigeration. In general, hyperbaric stored sliced cooked ham showed physicochemical parameters similar to the refrigerated samples.
In conclusion, these results show that HS at uncontrolled (naturally variable room tem-perature conditions at 25–37 ◦C) is a promising alternative to refrigeration for cooked ham preservation. To this new preservation technology, no energetic costs are associated throughout storage, compared to refrigeration, needing only energy to generate the pressure and decompress, since no energy is required to maintain the pressure
Preservation under pressure (hyperbaric storage) at 25ºC, 30ºC and 37ºC of a highly perishable dairy food and comparison with refrigeration
Hyperbaric storage (HS) under mild pressure of requeijão, a traditional Portuguese whey cheese, as a case study of a highly perishable dairy food, was evaluated as a possible energy costless alternative to refrigeration. Whey cheese was stored for 4 and 8 hours, at different pressure levels (0.1, 100 and 150 MPa) and temperatures (25°C, 30°C and 37°C), and the results were compared with refrigeration (4°C). Microbial
analyses showed that storage for 4 hours at 100 MPa was able to maintain microbial counts similar to refrigeration and initial load, ≈3 Log10 CFU/g, at all tested temperatures. By increasing the pressure to 150 MPa and the storage time to 8 hours, microbial loads were reduced to undetectable counts, with the exception for total aerobic mesophiles that were reduced to about ≈1 Log unit. HS in general maintained pH, water activity and lipid oxidation values, at levels similar to that in refrigeration
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