Removal of inorganic colour pigments from acrylonitrile butadiene styrene by dissolution-based recycling

Reinserting thermoplastic industrial scrap materials back into the production process must be feasible and cost-effective. Unfortunately, many thermoplastic materials contain colour pigments that cause undesired colour effects and, therefore, have to be removed before recycling. The purpose of this study was to reduce the inorganic colour pigments titanium dioxide, chromium(III) oxide and iron(III) oxide from acrylonitrile butadiene styrene. Based on experiences with dissolution-based polymer recycling, the two methods for removing these colour pigments studied in this project were filtration and centrifugation. Multiple laboratory-scale experiments were performed with two solvent formulations, acetone and CreaSolv^? SB. Using the filtration method, both solvent formulations achieved reduction rates of 80% for titanium and iron and 90% for chromium. While similar reduction rates were obtained with high-speed laboratory-type centrifuges for acetone solutions, the results for CreaSolv^? SB solutions were considerably lower under the same experimental conditions. Increasing the temperature or centrifugation speed, however, will also increase the reduction rates. Thereby, CreaSolv^? SB solutions become suitable for industrial-scale processes. This is important because industrial processes based on CreaSolv^? SB solutions are significantly safer than acetone-based processes.     

Integument and defence in larva and prepupa of a sawfly living on a semi-aquatic plant

The larvae of the sawfly Rhadinoceraea micans live and feed on a semi-aquatic plant, Iris pseudacorus, and their integument is strongly hydrophobic. The hydrophobicity is part of a chemical defence strategy, easy bleeding, also known from congeners. The prepupae burrow into the soil where they form a cocoon in which they pupate, thus implying different micro-environmental conditions. The cuticle structure and wetting defensive effectiveness of R. micans were compared between larvae and prepupae. The two stages were similarly well defended against attacking ants by the bleeding of a deterrent hemolymph, whereas they were dissimilar in the cuticle surface that presented sculptures and wax crystals at the larval stage only. The integument of prepupae was less structured, and hydrophilic. Larvae of R. micans exhibit, among sawflies, an exceptional cuticle structuring and we assume that they occupy this particular niche of a semi-aquatic environment to avoid encounters with ground-dwelling predators whereas prepupae may benefit from the chemical defence acquired at larval stage.     

Prenatally detected trisomy 4 and 6 mosaicism—cytogenetic results and clinical phenotype

We report on a live-born male with 46,XY/47,XY+4/47,XY,+6 mosaicism. Trisomy 4 mosaicism was detected by karyotyping chorionic villus samples (CVS) and was confirmed by the analysis of 16 metaphases obtained from cultured amniotic fluid cells. Eight metaphases were normal (46,XY), two had trisomy 4 (47,XY,+4), and two had trisomy 6 (47,XY,+6). Two postnatal chromosomal analyses of blood lymphocytes at birth and at the age of one week were normal. Chromosomal analysis of cultured skin fibroblasts from the right inguinal region at the age of 12 months revealed trisomy 4 (47,XY,+4) in 49 metaphases, trisomy 6 (47,XY,+6) in 2 metaphases, and a normal karyotype (46,XY) in 49 cells of the 100 analyzed metaphases, respectively. The main clinical findings consist of prenatal growth retardation, hypoplasia of the right side of the face, a dysplastic and posteriorly rotated right ear, a high vaulted palate, retrognathia, aplasia of the right thumb, hypoplasia of the fingernails, a deep sacral dimple, and patchy skin hypopigmentation of the right leg. When last seen at the age of 14 months, his development was nearly normal. Five patients with trisomy 4 mosaicism have been reported previously, but none with an additional trisomy 6 mosaicism. Copyright © 2003 John Wiley & Sons, Ltd.     

Platin im Regenabfluß einer Straße

Using platinum based catalytic converters, platinum is emitted with the exhaust gases and deposited on the roads, and in their vicinity (sewage treatment plants, rivers), which increases the platinum concentrations in aquatic eco-systems. To evaluate the platinum discharge from roads, the platinum concentration was measured in rainwater from a road with a traffic fre quency of 16,000 automobiles per day. The platinum content of the samples varies strongly dependent upon the previous dry period, and the intensity and duration of the rainfall. Platinum was measured in 18 run-off samples from various rainfall events. The maximum platinum concentrations showed values up to 1.1. μg/l. The median value was 15 ng/l. Analysis of a sample from one rainfall events shows that platinum has a well defined firstflush effect, similar to that of particular bound lead and copper. The good correlation between platinum and coarse suspended matter, coarse particular lead and copper indicates that platinum in road run-offs is frequently found to be particular bound. Under the assumption that the road has been completely washed off, the platinum deposition can be estimated to be 14 ng/(m²d).     

Amnion rupture sequence in a first trimester missed abortion

We report the diagnosis of amnion rupture sequence made by sonography and fetoscopy during the first trimester of gestation in a case of missed abortion. The investigation revealed a demised fetus with the characteristics of 9 weeks of development. The early fetus had an amnion adhesion at the tip of the nose and strands of amnion wrapped around the terminal phalanges of both feet. No defects in addition to the face and limb involvement were identified. The karyotype was normal: 46,XX. In the reported case, fetoscopy allowed confirmation of the sonographic diagnosis of an amnion rupture sequence in the first trimester of gestation and consequently helped to clarify the cause of abortion in this case of early fetal demise. Copyright © 2001 John Wiley & Sons, Ltd.     

A conceptual model of the social–ecological system of nature-based solutions in urban environments

This article provides a perspective on nature-based solutions. First, the argument is developed that nature-based solutions integrate social and ecological systems. Then, theoretical considerations relating to relational values, multifunctionality, transdisciplinarity, and polycentric governance are briefly outlined. Finally, a conceptual model of the social–ecological system of nature-based solutions is synthesised and presented. This conceptual model comprehensively defines the social and ecological external and internal systems that make up nature-based solutions, and identifies theoretical considerations that need to be addressed at different stages of their planning and implementation The model bridges the normative gaps of existing nature-based solution frameworks and could be used for consistent, comprehensive, and transferable comparisons internationally. The theoretical considerations addressed in this article inform practitioners, policymakers, and researchers about the essential components of nature-based solutions. The conceptual model can facilitate the identification of social and ecological interconnections within nature-based solutions and the range of stakeholders and disciplines involved.     

The influence of artificial sealing on the capillary barrier’s function

Regulations for the sealing of landfill sites require two independent sealing components. To satisfy this requirement, the combined capillary barrier was developed using impermeable sheeting placed between the capillary layer and the capillary block of the traditional capillary barrier. In this study, a numerical model is introduced based on hydraulic characteristics obtained by means of measurements of samples of capillary barrier materials. To make a comparison possible, samples of a laboratory investigated barrier were measured. Two laboratory experiments with a simple and a combined capillary barrier were repeated using the developed numerical model and good agreement between computed and measured results was found. Subsequently, the model was used for investigating the effect of failure of the artificial sheeting on the capillary barrier’s efficiency. The obtained results are presented and discussed.     

Towards a spatially explicit and quantitative vulnerability assessment of environmental change in Europe

Over the next century, society will increasingly be confronted with the impacts of global change (e.g. pollution, land use changes, and climate change). Multiple scenarios provide us with a range of possible changes in socio-economic trends, land uses and climate (i.e. exposure) and allow us to assess the response of ecosystems and changes in the services they provide (i.e. potential impacts). Since vulnerability to global change is less when society is able to adapt, it is important to provide decision makers with tools that will allow them to assess and compare the vulnerability of different sectors and regions to global change, taking into account exposure and sensitivity, as well as adaptive capacity. This paper presents a method that allows quantitative spatial analyses of the vulnerability of the human-environment system on a European scale. It is a first step towards providing stakeholders and policy makers with a spatially explicit portfolio of comparable projections of ecosystem services, providing a basis for discussion on the sustainable management of Europe’s natural resources.

Pre-mating sperm removal in the bushcricket Metaplastes ornatus Ramme 1931 (Orthoptera, Tettigonoidea, Phaneropteridae)

Summary Mating in the bushcricket Metaplastes ornatus Ramme 1931 entails a number of peculiar genital couplings that precede the transfer of the large spermatophore. During these phase-I couplings, the male introduces his specially structured subgenital plate into the female's genital chamber, performs back-and-forth movements, and turns her genital chamber inside out when he withdraws, whereupon the female carefully cleans her everted genital chamber with her mouthparts. During the last coupling (phase II) the male's subgenital plate is not introduced but the large spermatophore, which averages 22% of a male's body weight, is transferred. Counts of sperm in the spermathecae of females suggested that the phase-I couplings, which occur prior to spermatophore transfer, function to remove, or at least to reduce, the sperm of a female's previous mates. The form of the keel of the male's subgenital plate, its position within the female's genital tract during phase-I couplings, and the back-and-forth movements suggest that the male may stimulate release of sperm from the female's spermatheca by a mechanism similar to fertilization as eggs pass through the genital chamber during oviposition.