Analysis of dioxins and furans in environmental samples by GC-ion-trap MS/MS

The work aims to characterise PCDDs/Fs in environmental matrices by high resolution gas chromatography coupled to low resolution quadrupole ion-trap mass spectrometry (GC-QITMS/MS). In particular, the study was mainly focused in different environmental samples such as sewage sludge, soils, and sediments and in combustion residues as fly ashes. Previous experiences have already detected and quantified PCDDs/PCDFs in all matrices studied. Moreover, isomer-specific analysis of 2,3,7,8-PCDDs/Fs compounds corroborated good correlation between GC-QITMS/MS and a well-established technique such as high resolution mass spectrometry (HRMS). Finally, QC measures included the participation in intercalibration exercises. Successful results were achieved using GC-QITMS/MS in the analysis of fly ashes, soils and sediment materials. In general, GC-QITMS/MS constitutes an interesting alternative for routine analysis of dioxins in such as matrices.     

Effects of herbicide and insecticide interaction on soil entomofauna under maize crop

The aim of this study was to evaluate the impact of the herbicide mixture nicosulfuron + atrazine, with or without the insecticide chlorpyrifos, onto soil entomofauna under maize crop. The treatments, applied 25 days after maize emergence, were represented by a weeded control without insecticide and herbicide, a weeded control with chlorpyrifos, and mixtures of nicosulfuron + atrazine, with or without chlorpyrifos. Arthropods populations, on the soil surface, as well as inside the soil under maize, were principally represented by mites (Arachnida: Acari), decomposer collembolans (Hexapoda:Parainsecta:Collembola) and predator ants (Hymenoptera:Formicidae). The nicosulfuron + atrazine mixture with chlorpyrifos and the isolated chlorpyrifos reduced the population dynamics of all insect groups on the soil surface compared to the weeded control. In the soil, mite and ant populations were reduced after application of the herbicide mixture with chlorpyrifos and of the isolated chlorpyrifos.     

Male coloration and chick condition in blue-footed booby: a cross-fostering experiment

Sexual selection models suggest that female choice is based on male traits that indicate their genetic or environmental condition, consequently enhancing her reproductive success by direct or indirect benefits. We investigated the relationship between male foot colour and offspring condition in the blue-footed booby, a socially monogamous seabird, with conspicuous and variably condition-dependent coloured feet that are selected by females. In a cross-fostering experiment, we found that chick condition was related to the foot colour of the foster father and, to some extent, to the foot colour of the genetic father; thus overall, the fathers sexual ornamentation (genetic and foster) explained 32% of variance of chick condition. These data suggest that foot colour, a dynamic sexually selected trait, is mostly a signal of parental contribution. In species in which males provide parental care, females may choose mates with higher parental ability. Overall, our data suggest that colourful integuments are honest signals of parental ability.Communicated by J. Graves     

Symmetry, male dominance and female mate preferences in the Iberian rock lizard, Lacerta monticola

Female preference for dominant males is widespread and it is generally assumed that success in male-male competition reflects high quality. However, male dominance is not always attractive to females. Alternatively, relatively symmetric individuals may experience fitness advantages, but it remains to be determined whether males with more symmetrical secondary sexual traits experience advantages in both intra- and intersexual selection. We analysed the factors that determine dominance status in males of the lizard Lacerta monticola, and their relationship to female mate preference, estimated by the attractiveness of males' scents to females. Sexually dimorphic traits of this lizard (head size and femoral pores) appear to be advanced by different selection pressures. Males with relatively higher heads, which give them advantage in intrasexual contests, were more dominant. However, head size was unimportant to females, which preferred to be in areas marked by relatively heavier males, but also by males more symmetric in their counts of left and right femoral pores. Chemicals arising from the femoral pores and other glands might honestly indicate quality (i.e. related to the symmetry levels) of a male to females and may result from intersexual selection. Females may use this information because the only benefit of mate choice to female lizards may be genetic quality. Chemical signals may be more reliable and have a greater importance in sexual selection processes of lizards than has previously been considered.     

Spatial analysis of plant detritus processing in a Mediterranean river type: the case of the River Tirso Basin,Sardinia, Italy

The river continuum concept represents the most general framework addressing the spatial variation of both structure and function in river ecosystems.In the Mediterranean ecoregion,summer drought events and dams constitute the main sources of local disturbance to the structure and functioning of river ecosystems occurring in the river basin.In this study,we analysed patterns of spatial variation of detritus processing in a 7th order river of the Mediterranean ecoregion(River Tirso,Sardinia0Italy)and in three 4th order sub-basins which were exposed to different summer drought pressures.The study was carried out on phragmites australis and Alnus glutionsa leaf detritus at 31 field sites in seasonal field experiment Detritus processing rates were higher for Alnus glutionsa than for Phragmites australis plant detritus.Processing rates of Alnus glutionsa leaves varied among seasons and study sites from 0.006d^-1 to 0.189d^-1 and those of Phragmites australis leaves ranged from 0.0008d^-1 to 0.102d^-1,with the lowest values occurring at sites exposed to summer drought.Seasons and sites accounted for a significant proportion of such variability.Alder detritus decay rates generally decreased with increasing stream order,while reed detritus decay rates generallyincreased on the same spatial gradient.Summer drought events affected these spatial patterns of variation by influencing significantly the decay rates of both plant detritus.The comparisons among and within sub-basins showed strong negative influence of summer drought on detritus processing rates.Similarly,in the entire River Tirso basin decay rates were always lower at disturbed than at undisturbed sites for each stream order;decay rates of reed detritus remained lower at those sites even after the end of the disturbance events,while alder decay rates recovered rapidly from the summer drought perturbations.The different recovery of the processing rates of the two leaves could also explain the different patterns of spatial variation observed between the two leaves.     

Working conditions and sleepiness while driving among truck drivers

Objective: The objective of this study is to identify the role of working conditions as predictors of sleepiness while driving among truck drivers.

Methods: This was a cross-sectional study carried out among truck drivers who transported grains to Paranaguá Port, Paraná, Brazil. The truck drivers were interviewed and completed a self-administered questionnaire to collect data on sociodemographic and behavioral variables, working conditions, consumption of illicit psychoactive substances, and sleep patterns. Drivers were considered to be sleepy while driving if they reported a medium or high probability of napping while driving at night, during the daytime, or while stopped in traffic. The statistical analysis used logistic regression models progressively adjusted for age, behavioral variables, sleep duration, and other working conditions.

Results: In total, 670 male drivers, with a mean age of 41.9 (±11.1) years, were enrolled. The prevalence of sleepiness while driving was 31.5%. After model adjustments, the following working conditions were associated with sleepiness while driving: Distance from the last shipment of more than 1,000?km (odds ratio [OR]?=?1.54; 95% confidence interval [CI], 1.07–2.23) and a formal labor contract with a productivity-based salary (OR = 2.65; 95% CI, 1.86–3.78). Consumption of illicit psychoactive substances (OR = 1.99; 95% CI, 1.14–3.47) was also associated with sleepiness while driving.

Conclusions: Distance traveled and a formal labor contract with productivity-based earnings were the working conditions associated with sleepiness while driving, regardless of other working or behavioral characteristics, age, consumption of illicit psychoactive substances, and sleep duration.     

Early detection and evaluation of waste through sensorized containers for a collection monitoring application

The present study describes a novel application for use in the monitoring of municipal solid waste, based on distributed sensor technology and geographical information systems. Original field testing and evaluation of the application were carried out in Pudong, Shanghai (PR China).The local waste management system in Pudong features particular requirements related to the rapidly increasing rate of waste production. In view of the fact that collected waste is currently deployed to landfills or to incineration plants within the context investigated, the key aspects to be taken into account in waste collection procedures include monitoring of the overall amount of waste produced, quantitative measurement of the waste present at each collection point and identification of classes of material present in the collected waste. The case study described herein focuses particularly on the above mentioned aspects, proposing the implementation of a network of sensorized waste containers linked to a data management system.Containers used were equipped with a set of sensors mounted onto standard waste bins. The design, implementation and validation procedures applied are subsequently described. The main aim to be achieved by data collection and evaluation was to provide for feasibility analysis of the final device. Data pertaining to the content of waste containers, sampled and processed by means of devices validated on two purpose-designed prototypes, were therefore uploaded to a central monitoring server using GPRS connection. The data monitoring and management modules are integrated into an existing application used by local municipal authorities.A field test campaign was performed in the Pudong area. The system was evaluated in terms of real data flow from the network nodes (containers) as well as in terms of optimization functions, such as collection vehicle routing and scheduling. The most important outcomes obtained were related to calculations of waste weight and volume. The latter data were subsequently used as parameters for the routing optimization of collection trucks and material density evaluation.     

Dissipation of fenoxycarb and pyriproxyfen in fresh and canned peach

The objective of this work was to determine the dissipation of fenoxycarb and pyriproxyfen in fresh and canned peaches in order to know the levels of residues that can reach consumers in real circumstances. Two field dissipation studies were carried out, one of them at the pre-harvest interval (PHI) with good agricultural practice (GAP) and the other one in a situation of critical agricultural practice (CAP). Two canning dissipation studies were carried out for samples from both agricultural situations in an industrial pilot plant and the dissipation was determined in each relevant step. An analytical methodology was used including acetone-dichloromethane extraction, purification and analysis by liquid chromatography and diode array detection (LC-DAD) with a limit of quantification (LOQ) of 0.05 mg/kg. It was validated under SANCO/10232/2006 Guidelines. These pesticides complied with the official maximum residue limits (MRLs) in peaches at the PHI with good agricultural practices. In hypothetical situation of a second application at the PHI, fenoxycarb and pyriproxyfen residues were above the MRLs in peaches. The canning study reduced the residues to no detectable levels in the cans for consumers.     

Impacts of changes in land use and fragmentation patterns on Atlantic coastal forests in northern Spain

Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (northwestern Spain). We used orthoimages and a set of standard landscape metrics to determine transitions between land cover classes and to examine forest distribution patterns. Eucalypt plantations showed the greatest increase in area (197%) over time. Furthermore, transitions to eucalypt plantations were found in all major land cover classes. Forest showed a net decline of 20% in total area and represented 30% of the landscape area in 2003. Forest losses were mainly due to eucalypt plantations and the building of a water reservoir, while forest gains were due to increases in shrubland, meadows and cultivated fields which had been recolonised. Forest patch size and core area decreased, and edge length increased over time. In turn, increases were obtained in mean distance between forest patches, and in adjacency to eucalypt plantations and to a water reservoir. These results suggest an increase in forest fragmentation from 1957 to 2003, as well as a change in the nature of the habitat surrounding forest patches. This study shows that land use changes, mostly from eucalypt plantation intensification, negatively affected forested habitats, although some regeneration was ongoing through ecological succession from land abandonment.