Pregnancy outcome after transcervical cvs with a flexible biopsy forceps: Evaluation of risk factors

The pregnancy outcome of 1936 women who had transcervical chorionic villus sampling (CVS) with a flexible biopsy forceps was evaluated. Follow-up until 4 weeks after delivery was 99.4 per cent. Various patient- and procedure-related risk factors for spontaneous loss (fetal or neonatal death) were analysed using stepwise logistic regression analysis. The overall spontaneous loss rate was 4.5 per cent. Factors found to be significantly associated with spontaneous loss were quantity of villi ≤ 15 mg (relative risk (RR) 2.13), a history of first-trimester miscarriage (RR 1.87) or delivery between 16 and 27 weeks (RR 3.87), cervical culture positive for anaerobes (RR 4.52) or group B streptococcus (RR 3.62), post-procedural bleeding >3 days (RR 1.99), and multiple insertions (RR 2.64). Significant differences in loss rates between individual operators were found. A learning effect was not present. There were no infants born with terminal transversal limb anomalies in our series.     

Could the predation risk hypothesis explain large-scale spatial sexual segregation in fallow deer (<Emphasis Type="Italic">Dama dama</Emphasis>)?

Large-scale spatial segregation was assessed by means of radio-telemetry in 48 fallow deer studied for 4 years. Three hypotheses have traditionally been used to explain sexual segregation: (1) the predation risk hypothesis, (2) the forage selection hypothesis, (3) the activity budget hypothesis. The first of these seems to be a valid explanation of large-scale segregation in fallow deer at San Rossore, where the use by the two sexes of areas characterized by intense anthropic disturbance, during the day, was compared with other areas not affected by human pressure. Males showed a high use of disturbed areas, both during the day and the night, with the exception of the rutting period, when they reached more remote areas to mate. Females frequented disturbed areas only during the night, with the exception of the birth period, when sexual segregation peaked because females never used these areas, not even during the night. The forage selection hypothesis was invalid on a large scale, considering that no differences between the degree of day and night sexual segregation were to be expected. However, the predation risk hypothesis seems not to be a valid explanation of small-scale sexual segregation, when further subdivisions of disturbed areas are considered, because sexes proved to be segregated also during the night in the area they both used. This emphasizes both the importance of scale in understanding ecological processes, since a combination of many different factors may be responsible for the evolution of sexual segregation in ungulates, and the importance of human pressure in influencing deer behaviour.Communicated by T. Czeschlik     

Heavy metals in top core sediments from the southern Campania shelf (Italy): Hints to define large-scale geochemical backgrounds

The results of a geochemical survey carried out on the southern Campania shelf (southern Italy) are illustrated, offering a tempting opportunity to discuss the statement and definition of regional geochemical backgrounds for selected heavy metals. A total of 104 top core sediments, collected on average 1.5 km from one another and covering a shelf area of about 1300 km², were analysed for grain size, organic carbon content (OC), and heavy-metal (As, Al, Fe, Cd, V, Cr, Zn, Cu, Ni, Hg, and Pb) concentrations. The characteristics of the area, scarcely influenced by industrial activities, and the extensive data set, make this study suitable for an appropriate multivariate and spatial geostatistical methodologies used for i) a reliable definition of large-scale marine sediments' geochemical backgrounds and ii) an accurate discrimination of different geological controls on trace-element distribution patterns. Enrichment factors estimated with respect to both the average shale composition and the weighted average metal concentrations measured in inland soils rule out significant anthropogenic inputs. A spatial-geostatistics approach (kriging of spatial component based on an accurate implementation of variographic surveying) was applied, and this is proposed as an appropriate quantitative methodology to define the geochemical backgrounds for the different heavy metals. Two nested spatial structures were identified for some of the heavy metals, thus allowing clear identification of local and regional geochemical controls related to the different spatial variability of grain size.     

Living in a “stethoscope”: burrow-acoustics promote auditory specializations in subterranean rodents

Subterranean mammals rely to a great extent on audition for communication and to be alerted to danger. The only hitherto published report on burrow acoustics revealed that in tunnels of blind mole-rats (Spalax ehrenbergi), airborne sounds of 440 Hz propagated best whereas lower and higher frequencies were effectively attenuated. Morpho-functional analyses classify the ear of subterranean mammals as a low-sensitivity and low-frequency device. Concordantly, hearing is characterized by low sensitivity and a restricted frequency range tuned to low frequencies (0.5–4 kHz). Some authors considered the restricted hearing in subterranean mammals vestigial and degenerate due to under-stimulation. In contrast to this view stand a rich (mostly low-frequency) vocal repertoire and progressive structural specializations of the middle and inner ear. Thus, other authors considered these hearing characteristics adaptive. To test the hypothesis that acoustical environment in burrows of different species of subterranean mammals is similar, we measured sound attenuation in burrows of Fukomys mole-rats (formerly known as Cryptomys, cf. Kock et al. 2006) of two differently sized species at different locations in Zambia. We show that in these burrows, low-frequency sounds (200–800 Hz) are not only least attenuated but also their amplitude may be amplified like in a stethoscope (up to two times over 1 m). We suggest that hearing sensitivity has decreased during evolution of subterranean mammals to avoid over-stimulation of the ear in their natural environment. We dedicate this work to Mathias Kawalika, who died in March 2006.     

Endogenous growth,asymmetric trade and resource dependence

The aggregate income of oil-exporting countries relative to that of oil-poor countries has been remarkably constant in recent decades, despite the existence of structural gaps in productivity growth rates. This stylized fact is rationalized in an endogenous growth model of asymmetric trade where resource-poor and resource-rich economies display productivity differences but stable income shares due to terms-of-trade dynamics. The model yields two testable predictions that deserve empirical scrutiny: (i) the asymmetric impact, between exporters and importers, of national taxes on resource use on income shares and (ii) the inverse relation between terms-of-trade dynamics and total factor productivity growth.     

Evaluation of levels, sources and distribution of toxic elements in PM10 in a suburban industrial region, Rio de Janeiro, Brazil

The Oswaldo Cruz Foundation Campus (FIOCRUZ), in a suburban region of the city of Rio de Janeiro, was selected as a case study to assess the pollution released from vehicle and industrial facilities in Basin III, the most polluted area of the city. Concentrations of particulate matter (PM10) and trace metals in airborne particles were determined in an intensive field campaign. The samplings were performed every six days for 24 h periods, using a PM10 high volume sampler, from September 2004 to August 2005. PM10 mass concentrations were determined gravimetrically and the metals by ICP-OES. For PM10, the arithmetic mean for the period is 169 ± 42 μg m⁻³ which is 3.4 times the national recommended standard of 50 μg m⁻³. Additionally, 51% of the samplings exceeded the recommended 24 h limit of 150 μg m⁻³. Ca, Mg, Fe, Zn and Al were the metals that presented the higher concentrations. The correlation matrix gave two main clusters and three significant principal components (PC). Both PC1 and PC2 are associated to crustal, vehicular and industrial emissions while PC3 is mainly associated to geological material. Enrichment factors for Zn, Cu, Cd and Pb indicate that for these elements, anthropic sources prevail over natural inputs. PM10 levels showed a good correlation with hospital admissions for respiratory diseases in children and elderly people.     

LCA and economic evaluation of landfill leachate and gas technologies

Landfills receiving a mix of waste, including organics, have developed dramatically over the last 3-4 decades; from open dumps to engineered facilities with extensive controls on leachate and gas. The conventional municipal landfill will in most climates produce a highly contaminated leachate and a significant amount of landfill gas. Leachate controls may include bottom liners and leachate collection systems as well as leachate treatment prior to discharge to surface water. Gas controls may include oxidizing top covers, gas collection systems with flares or gas utilization systems for production of electricity and heat.The importance of leachate and gas control measures in reducing the overall environmental impact from a conventional landfill was assessed by life-cycle-assessment (LCA). The direct cost for the measures were also estimated providing a basis for assessing which measures are the most cost-effective in reducing the impact from a conventional landfill. This was done by modeling landfills ranging from a simple open dump to highly engineered conventional landfills with energy recovery in form of heat or electricity. The modeling was done in the waste LCA model EASEWASTE. The results showed drastic improvements for most impact categories. Global warming went from an impact of 0.1 person equivalent (PE) for the dump to −0.05 PE for the best design. Similar improvements were found for photochemical ozone formation (0.02 PE to 0.002 PE) and stratospheric ozone formation (0.04 PE to 0.001 PE).For the toxic and spoiled groundwater impact categories the trend is not as clear. The reason for this was that the load to the environment shifted as more technologies were used. For the dump landfill the main impacts were impacts for spoiled groundwater due to lack of leachate collection, 2.3 PE down to 0.4 PE when leachate is collected. However, at the same time, leachate collection causes a slight increase in eco-toxicity and human toxicity via water (0.007E to 0.013PE and 0.002 to 0.003 PE respectively). The reason for this is that even if the leachate is treated, slight amounts of contaminants are released through emissions of treated wastewater to surface waters.The largest environmental improvement with regard to the direct cost of the landfill was the capping and leachate treatment system. The capping, though very cheap to establish, gave a huge benefit in lowered impacts, the leachate collection system though expensive gave large benefits as well. The other gas measures were found to give further improvements, for a minor increase in cost.     

Contribution of individual waste fractions to the environmental impacts from landfilling of municipal solid waste

A number of LCA-based studies have reported on the environmental performance of landfilling of mixed waste, but little is known about the relative contributions of individual waste fractions to the overall impact potentials estimated for the mixed waste. In this paper, an empirical model has been used to estimate the emissions to the environment from landfilling of individual waste fractions. By means of the LCA-model EASEWASTE, the emissions estimated have been used to quantify how much of the overall impact potential for each impact category is to be attributed to the individual waste fractions. Impact potentials are estimated for 1 tonne of mixed waste disposed off in a conventional landfill with bottom liner, leachate collection and treatment and gas collection and utilization for electricity generation. All the environmental aspects are accounted for 100 years after disposal and several impact categories have been considered, including standard categories, toxicity-related categories and groundwater contamination.Amongst the standard and toxicity-related categories, the highest potential impact is estimated for human toxicity via soil (HTs; 12 mPE/tonne). This is mostly caused by leaching of heavy metals from ashes (e.g. residues from roads cleaning and vacuum cleaning bags), batteries, paper and metals. On the other hand, substantial net environmental savings are estimated for the categories Global Warming (GW; ?31 mPE/tonne) and Eco-Toxicity in water chronic (ETwc; ?53 mPE/tonne). These savings are mostly determined by the waste fractions characterized by a high content of biogenic carbon (paper, organics, other combustible waste). These savings are due to emissions from energy generation avoided by landfill gas utilization, and by the storage of biogenic carbon in the landfill due to incomplete waste degradation.