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361.
Rui?RebeloEmail author Castro?Barbosa José?P.?Granadeiro Bucar?Indjai Bruno?Novais Gon?alo?M.?Rosa Paulo?Catry 《Marine Biology》2012,159(3):613-620
In marine turtles, the sex of an individual is determined by temperatures experienced during embryonic development. Gonad histological observation is still the only reliable way to determine hatchling sex, hampering the study of reproduction and of the demographic consequences of context-dependent sex-ratios, a subject of interest in a warming planet. We investigated whether hatchling remains from predation by Ocypode cursor can be used to estimate sex-ratio trends in a green turtle rookery at Poilão, Guinea-Bissau (10°52′N, 15°43′W). Sex could be readily determined in 77 and 79% of the predated hatchlings in 2008 and 2009, respectively. By comparing hatchlings killed by crabs, hatchlings accidentally dying on the reefs, and live hatchlings, we show that ghost crabs select the smaller prey, but do not select according to hatchling sex, which is explained by the lack of hatchling size dimorphism in this population. The proportion of male hatchlings was 0.45 ± 0.06 and 0.15 ± 0.06 for early and late-season clutches, respectively, these differences most likely being explained by rainfall. Using leftovers from predation by crabs may be a good solution to non-invasively monitor broad trends in sex-ratios of sea turtles. 相似文献
362.
Tracking the evolution of research in waste recycling science (WRS) can be valuable for environmental agencies, as well as for recycling businesses. Maps of science are visual, easily readable representations of the cognitive structure of a branch of science, a particular area of research or the global spectrum of scientific production. They are generally built upon evidence collected from reliable sources of information, such as patent and scientific publication databases. This study uses the methodology developed by Rafols et al. (2010) to make a "double overlay map" of WRS upon a basemap reflecting the cognitive structure of all journal-published science, for the years 2005 and 2010. The analysis has taken into account the cognitive areas where WRS articles are published and the areas from where it takes its intellectual nourishing, paying special attention to the growing trends of the key areas. Interpretation of results lead to the conclusion that extraction of energy from waste will probably be an important research topic in the future, along with developments in general chemistry and chemical engineering oriented to the recovery of valuable materials from waste. Agricultural and material sciences, together with the combined economics, politics and geography field, are areas with which WRS shows a relevant and ever increasing cognitive relationship. 相似文献
363.
Joan Solé Albert Sans Magí Riba Gloria Rosell Esmeralda Rosa Lourdes Muñoz Maria Pilar Bosch Angel Guerrero 《Chemoecology》2008,18(2):99-108
Summary. The differing antagonist activity of (Z)-13-hexadecen-2-one (Z11 – 14 :MK, 1) and its 1,1,1-trifluoro derivative (Z11 –14 :TFMK, 2), two closely related analogues of the European corn borer pheromone Ostrinia nubilalis (Z strain), and their rationale is reported. Both chemicals exhibited some electrophysiological activity, and topical application
of 10 pg of pheromone analogue on male antennae was sufficient to induce significantly lower depolarization responses to the
pheromone versus untreated insects. In a wind tunnel, the number of European corn borer males attracted to sources containing
mixtures of 1 + pheromone in ratios ≥ 1 :1 was significantly lower than the number attracted to a source containing pheromone alone. Source
contact behaviour was dramatically impaired when the 1 + pheromone blend reached a ratio of 10 :1, in which only 2% of males displayed source contact in the presence of antagonist.
When compound 1 was present at the source, males usually flew upwind with occasional downwind reversals; when compound 2 was present at the lure, males performed wider crosswind reversals, with little progress toward the source. In the field,
traps baited with mixtures of both compounds with the pheromone in ratios of 5 :1 and 10 :1 elicited a significantly decreased
number of male catches. In esterase inhibition assays, compound 2 was a potent inhibitor (IC50 = 70 nM), whereas the non-fluorinated compound 1 was not. The different activity of both compounds is presumed to be due to different mechanisms of action; considerations
for using methyl ketone analogues as new behavioural antagonists of the pheromone are outlined. 相似文献
364.
365.
Rosa M. Pintó M. Isabel Costafreda Francisco J. Pérez-Rodriguez Lucía D’Andrea Albert Bosch 《Food and environmental virology》2010,2(3):127-135
Hepatitis A is the most common among all hepatitis worldwide in spite of an efficient vaccine and improved hygiene. Shellfish-borne
outbreaks are still of major concern causing hundreds of cases and huge economical losses in the present context of global
food trade. Hepatitis A virus (HAV) is a unique picornavirus with many differences in its molecular biology including both
its incapacity to induce the inhibition of the cellular protein synthesis and a highly biased and deoptimized codon usage
with respect the cell. The final goal of this intriguing strategy seems to be the need for a fine-tuning control of the translation
kinetics, particularly at the capsid coding region, and the underlying mechanism is the use of a right combination of common
and rare codons to allow a regulated ribosome traffic rate thus ensuring the proper protein folding. Capsid folding is critical
to warrant a high environmental stability for a virus transmitted through the fecal–oral route with long extracorporeal periods. 相似文献
366.
The discrimination of infectious and inactivated viruses remains a key obstacle when using quantitative RT-PCR (RT-qPCR) to
quantify enteric viruses. In this study, propidium monoazide (PMA) and RNase pretreatments were evaluated for the detection
and quantification of infectious hepatitis A virus (HAV). For thermally inactivated HAV, PMA treatment was more effective
than RNase treatment for differentiating infectious and inactivated viruses, with HAV titers reduced by more than 2.4 log10 units. Results showed that combining 50 μM of PMA and RT-qPCR selectively quantify infectious HAV in media suspensions. Therefore,
PMA treatment previous to RT-qPCR detection is a promising alternative to assess HAV infectivity. 相似文献
367.
Introduction
The current study explored the association between the business cycle and the incidence of workplace injuries to identify cyclically sensitive industries and the relative contribution of physical capital and labor utilization within industries.Method
Bureau of Labor Statistics nonfatal injury rates from 1976 through 2007 were examined across five industry sectors with respect to several macroeconomic indicators. Within industries, injury associations with utilization of labor and physical capital over time were tested using time series regression methods.Results
Pro-cyclical associations between business cycle indicators and injury incidence were observed in mining, construction, and manufacturing but not in agriculture or trade. Physical capital utilization was the highest potential contributor to injuries in mining while labor utilization was the highest potential contributor in construction. In manufacturing each effect had a similar association with injuries.Conclusion
The incidence of workplace injury is associated with the business cycle. However, the degree of association and the mechanisms through with the business cycle affects the incidence of workplace injuries was not the same across industries.Impact on Industry
The results suggest that firms in the construction, manufacturing, and mining industries should take additional precautionary safety measures during cyclical upturns. Potential differences among industries in the mechanisms through which the business cycle affects injury incidence suggest different protective strategies for those industries. For example, in construction, additional efforts might be undertaken to ensure workers are adequately trained and not excessively fatigued, while safety procedures continue to be followed even during boom times. 相似文献368.
369.
Devesa-Rey R Díaz-Fierros F Barral MT 《Environmental monitoring and assessment》2011,179(1-4):371-388
The metals distribution in the bed sediments of the Anllóns River was studied, with special emphasis on the evaluation of the metal distribution as a function of the granulometric fraction chosen for the analysis. Statistical significant differences between the distribution of K, Ca, Cr, Mn, As, Rb, Sr and Nb in the bulk (<2 mm) and fine fraction (<63 μm) were not found. Fe, Ni, Cu, Ga, Zr, Zn and Pb commonly appear in higher concentrations in the fine fraction, whereas Ti appears in higher concentrations in the bulk fraction. In general, it was observed that contamination phenomena tend to equalise the concentrations of both fractions, and this was mainly explained as the result of two processes. First, the formation of coatings over sands and, second, the formation of large aggregates (pseudo-sands) at sites located over basic rocks, whose chemical behaviour is closer to that of clays and could be responsible for significant adsorption processes. Normalisation techniques to evaluate contamination were applied by testing Nb, Sr, Rb or Ga as normaliser elements and by using crustal or shale average values for background concentrations. The most satisfactory result was obtained when using shale average values and Ga as the normaliser element. Arsenic was identified as the main contaminant of the basin, exceeding in all cases the low-effect reference values proposed by sediment quality guidelines and in two cases the medium-effect reference values. These sites were identified by multivariate techniques, which allow differentiating site 10 as affected by anthropogenic inputs related to past mining activities. 相似文献
370.
Nuria Castell Enrique Mantilla Ariel F. Stein Rosa Salvador Millán Millán 《Environmental Modeling and Assessment》2011,16(6):565-576
During the central months of the year, southwestern Spain is under strong insolation and weak synoptic forcing, promoting
the development of sea breezes and mountain-induced winds and creating recirculations of pollutants. The complex topography
of the Southwestern Iberia Peninsula induces the formation of vertical layers, into which the pollutants are injected and
subjected to long-distance transport and compensatory subsidence. The characteristics of these highly complex flows have important
effects on the pollutant dispersion. Air pollution studies in very complex terrains require high-resolution modelling for
resolving the flow dynamics. This paper shows the results obtained from using the MM5-CAMx multiscale-nested air quality model
to relate the sensitivity regimes for ozone, nitrogen oxides and volatile organic compounds in an area of high geographical
complexity. The article assesses the impact on the hourly and eight-hourly maximum daily ozone concentrations of four reduction
strategies during two ozone pollution episodes. This analysis of the ozone response has led to a preliminary evaluation of
the effectiveness of the most common control strategies: traffic, industry, mixed traffic and industry, and closure of some
of the largest industries (oil and petrochemical refineries). Photochemical indicators show that ozone chemistry in southwestern
Spain is strongly sensitive to NO
x
. However, volatile organic compound-sensitive points are found in areas with anthropogenic influence (highways, cities and
industrial parks). Our results indicate that reductions in road traffic lead to ozone reductions over large areas, whereas
reductions in industrial emissions, despite sometimes showing greater decreases in the maximum hourly and eight-hourly ground-level
ozone levels, lead to ozone reductions in a local area only. In the control study case, with the oil refinery and the petrochemical
plants closed, decreases in ozone hourly concentrations are up to 40% higher than in the other emission control scenarios
studied. This analysis provides an assessment of the effectiveness of different policies for controlling precursor emissions
by comparing the modelled results for different scenarios. 相似文献