3,709 research outputs found
Occupational and Environmental Risks from Mancozeb in Aviation Facilities in the Banana Producing Area of Teapa, Tabasco, Mexico
Purpose: To identify occupational risks and practices in the four aerial fumigation facilities in the Sierra banana growing region and to evaluate environmental impacts from Mancozeb use.Methods: Occupational health risks were identified and practices in the four aerial fumigation facilities in the Sierra banana growing region were documented. Semi-structured interviews were conducted with installation managers. To evaluate environmental impact, samples of water and soil were collected and analysed in an acute toxicity bioassay with Vibrio fischeri, using uncontaminated soil and water to establish background levels.Results: Even in the largest and best-equipped facility, serious risks to workers’ health were encountered from inadequate use of protective equipment by workers. Furthermore, excessive use of pesticide, lack of re-use of unused product, poor facility design and poor use of wash-water were observed, resulting in maximum toxicity of > 5 times background in discharged water. Parallel soil samples were > 20 times more toxic than background, being most toxic at > 0.5 km from the discharge point.Conclusion: Areas of opportunity to improve worker health and the environment include proper and consistent use of protective equipment, re-use of unused product, wastewater reduction and appropriate wastewater treatment.Keywords: Black Sigatoka, Ethylene thiourea, Fumigation, Pesticide, Mancozeb, Airports, Microtox, Vibrio fischeri, Occupational health risks, Toxicit
Diurnal variability of inner-shelf circulation in the lee of a cape under upwelling conditions.
The nearshore circulation in the lee of a cape under upwelling conditions was studied using in-situ data from 3
consecutive summers (2006–2008). Focus was given to a period between 20 July and 04 August 2006 to study
the diurnal variability of the cross-shelf circulation. This period was chosen because it had a steady upwellingfavourable
wind condition modulated by a diurnal cycle much similar to sea breeze.
The daily variability of the observed cross-shelf circulation consisted of three distinct periods: a morning
period with a 3-layer vertical structure with onshore velocities at mid-depth, a mid-day period where the flow is
reversed and has a 2-layer structure with onshore velocities at the surface and offshore flow below, and, lastly, in
the evening, a 2-layer period with intensified offshore velocities at the surface and onshore flow at the bottom.
The observed cross-shelf circulation showed a peculiar vertical shape and diurnal variability different from
several other systems described in literature. We hypothesize that the flow reversal of the cross-shelf circulation
results as a response to the rapid change of the wind magnitude and direction at mid-day with the presence of
the cape north of the mooring site influencing this response.
A numerical modelling experiment exclusively forced by winds simulated successfully most of the circulation
at the ADCP site, especially the mid-day reversal and the evening's upwelling-type structure. This supports the
hypothesis that the cross-shelf circulation at diurnal timescales is mostly wind-driven. By analysing the 3D
circulation in the vicinity of Cape Sines we came to the conclusion that the diurnal variability of the wind and the
flow interaction with topography are responsible for the circulation variability at the ADCP site, though only a
small region in the south of the cape showed a similar diurnal variability.
The fact that the wind diurnally undergoes relaxation and intensification strongly affects the circulation,
promoting superficial onshore flows in the leeside of Cape Sines. Despite the small-scale nature of the observed
cross-shelf circulation, onshore flows as the ones described in this study can be particularly helpful to
understand the transport and settlement of larvae in this region and in other regions with similar topography
and wind characteristics.We thank D. Jacinto and T. Silva for help during field work and the
Port of Sines Authority (APS) for providing oceanographic and
meteorological data. Financial support was provided by FCT (POCI/
MAR/57630/2004; PTDC/BIA-BEC/103734/2008 and PEst-OE/
MAR/UIO199/2011). The simulations were preformed in the computational
facilities provided under FCT contract RECI/GEO-MET/0380/
2012. Luísa Lamas was funded by the FCT under a Ph.D. grant (SFRH/
BD/69533/2010)
Noncompaction Cardiomyopathy. A Review of Eight Cases
A miocardiopatia não compactada isolada é
uma doença geneticamente determinada
cuja patogénese parece envolver uma
paragem no desenvolvimento do
endomiocárdio. Morfologicamente
caracteriza-se pela presença de
trabeculações proeminentes separadas por
profundos recessos preenchidos por fluxo e
como tal por Doppler a cor no estudo
ecocardiográfico. No sentido de melhor
caracterizar esta entidade recentemente
descrita, de prognóstico pouco esclarecido,
fazemos uma revisão dos casos
diagnosticados no nosso hospital,
descrevendo as características clínicas,
electrocardiográficas e ecocardiográficas,
bem como a terapêutica instituída e
seguimento clínico. A propósito da revisão
dos casos, é feita uma exposição e discussão
da literatura mais relevante relativamente a
etiopatogenia, clínica, critérios de
diagnóstico, terapêutica e prognóstico
Correcting pervasive errors in RNA crystallography through enumerative structure prediction
Three-dimensional RNA models fitted into crystallographic density maps
exhibit pervasive conformational ambiguities, geometric errors and steric
clashes. To address these problems, we present enumerative real-space
refinement assisted by electron density under Rosetta (ERRASER), coupled to
Python-based hierarchical environment for integrated 'xtallography' (PHENIX)
diffraction-based refinement. On 24 data sets, ERRASER automatically corrects
the majority of MolProbity-assessed errors, improves the average Rfree factor,
resolves functionally important discrepancies in noncanonical structure and
refines low-resolution models to better match higher-resolution models
Unusual but consistent latitudinal patterns in macroalgal habitats and their invertebrate communities across two countries
Aim: The physical characteristics of biogenic habitats and environmental conditions are important determinants of biodiversity, yet their relative importance can change across spatial scales. We aimed to understand how relationships between the physical characteristics of macroalgal habitats and their invertebrate communities varied across spatial scales and whether general ecological patterns occurred across two countries. Location: Eighteen sites across the temperate east coasts of Australia (over 1,300 km) and New Zealand (over 1,000 km), with the latitudinal gradient in the two countries overlapping by 6.73 decimal degrees. Time period: January to early April 2012. Major taxa studied: Three intertidal macroalgal habitats in each country and the invertebrate communities within them. Methods: We measured variation in patch- and individual-level characteristics of macroalgal habitats and their invertebrate communities. Patterns in macroalgal characteristics and communities were compared across latitude, and at smaller spatial scales, and correlated with 26 abiotic environmental variables using multiple multivariate analyses. Results: Separately, macroalgal habitat characteristics and communities showed unusual but consistent nonlinear latitudinal patterns, with greater similarity among sites at the edges of the sampled distribution (i.e., north and south) than at centrally located sites. Macroalgal characteristics did not correlate with a particular set of environmental variables; however, communities were structured by sea surface temperature at the country scale and by macroalgal habitat type and biomass within countries. Anthropogenic variables were also important and may have contributed to the unusual nonlinear patterns observed between macroalgal characteristics and communities across latitude. Main conclusions: Our results support other studies showing that large-scale patterns can emerge from systems where there is high local-scale variability. The results show that communities within macroalgal habitats respond to both the physical characteristics of the habitat and external environmental conditions (e.g., temperature), suggesting that local-scale environmental factors, including anthropogenic stressors, may modulate environmental gradients over larger scales
Stem cell differentiation increases membrane-actin adhesion regulating cell blebability, migration and mechanics
This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder in order to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/K. S. is funded by an EPSRC PhD studentship. S.T. is funded by an EU Marie Curie Intra European Fellowship (GENOMICDIFF)
APLICACIÓN DE TRATAMIENTOS TÉRMICOS A FRUTOS DE AGUACATE PARA PROLONGAR SU VIDA DE ANAQUEL
Esta revisión resume los avances que han tenido los tratamientos térmicos (TT) utilizados para prolongar la vida útil del aguacate. Las tecnologías que se han venido utilizando a través del tiempo se pueden dividir en aire caliente (AC), vapor caliente (VC), agua caliente (AGC), exposición a luz solar (LS) y radiofrecuencia (RF). Los estudios muestran inconsistencia en sus resultados, debido a que la respuesta fisiológica del fruto de aguacate depende de la variedad, estación del año, lugar de recolección, prácticas de producción y falta de uniformidad en el calentamiento, la exposición o no al sol. Los TT que presentan mejores resultados en mantener la firmeza, retrasar la producción de etileno, disminución de la fuga de electrólitos y menor DF, han sido la LS, AGC y la combinación entre ellos. La exposición a LS induce estrés térmico diurno que aumenta la expresión de las proteínas del choque térmico (HSP17 y HSP70) que pre-condiciona al aguacate a resistir la aplicación de AGC a 50 ºC y el posterior almacenamiento a 0,5 ºC por 28 días
The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study
During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors
A functional connection between translation elongation and protein folding at the ribosome exit tunnel in Saccharomyces cerevisiae
Proteostasis needs to be tightly controlled to meet the cellular demand for correctly de novo folded proteins and to avoid protein aggregation. While a coupling between translation rate and co-translational folding, likely involving an interplay between the ribosome and its associated chaperones, clearly appears to exist, the underlying mechanisms and the contribution of ribosomal proteins remain to be explored. The ribosomal protein uL3 contains a long internal loop whose tip region is in close proximity to the ribosomal peptidyl transferase center. Intriguingly, the rpl3[W255C] allele, in which the residue making the closest contact to this catalytic site is mutated, affects diverse aspects of ribosome biogenesis and function. Here, we have uncovered, by performing a synthetic lethal screen with this allele, an unexpected link between translation and the folding of nascent proteins by the ribosome-associated Ssb-RAC chaperone system. Our results reveal that uL3 and Ssb-RAC cooperate to prevent 80S ribosomes from piling up within the 5′ region of mRNAs early on during translation elongation. Together, our study provides compelling in vivo evidence for a functional connection between peptide bond formation at the peptidyl transferase center and chaperone-assisted de novo folding of nascent polypeptides at the solvent-side of the peptide exit tunnel
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