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71.
In Switzerland many kinds of waste, e.g. paper, metals, electrical and electronic equipment are separately collected and recycled to a large extent. The residual amount of municipal solid waste (MSW) has to be thermally treated before final disposal. Efforts to recover valuable metals from incineration residues have recently increased. However, the resource potential of critical elements in the waste input (sources) and their partitioning into recyclable fractions and residues (fate) is unknown. Therefore, a substance flow analysis (SFA) for 31 elements including precious metals (Au, Ag), platinum metal group elements (Pt, Rh) and rare earth elements (La, Ce, etc.) has been conducted in a solid waste incinerator (SWI) with a state-of-the-art bottom ash treatment according to the Thermo-Re® concept. The SFA allowed the determination of the element partitioning in the SWI, as well as the elemental composition of the MSW by indirect analysis. The results show that the waste-input contains substantial quantities of precious metals, such as 0.4 ± 0.2 mg/kg Au and 5.3 ± 0.7 mg/kg Ag. Many of the valuable substances, such as Au and Ag are enriched in specific outputs (e.g. non-ferrous metal fractions) and are therefore recoverable. As the precious metal content in MSW is expected to rise due to its increasing application in complex consumer products, the results of this study are essential for the improvement of resource recovery in the Thermo-Re® process.  相似文献   
72.
The aim of this review is to assess the ethical implications of finfish aquaculture, regarding fish welfare and environmental aspects. The finfish aquaculture industry has grown substantially the last decades, both as a result of the over-fishing of wild fish populations, and because of the increasing consumer demand for fish meat. As the industry is growing, a significant amount of research on the subject is being conducted, monitoring the effects of aquaculture on the environment and on animal welfare. The areas of concern when it comes to animal welfare have here been divided into four different stages: breeding period; growth period; capturing and handling; and slaughter. Besides these stages, this report includes a chapter on the current evidence of fish sentience, since this issue is still being debated among biologists. However, most biologists are at present acknowledging the probability of fish being sentient creatures. Current aquaculture practices are affecting fish welfare during all four of the cited stages, both on physical and mental levels, as well as on the ability of fish to carry out natural behaviors. The effect fish farming has on the environment is here separated into five different categories: the decline of wild fish populations; waste and chemical discharge; loss of habitat; spreading of diseases; and invasion of exotic organisms. There is evidence of severe negative effects on the environment when looking at these five categories, even when considering the difficulty of studying environmental effects, due to the closely interacting variables. The ethical arguments and scientific evidences here reviewed have not all come to the same conclusions. Nevertheless, the general agreement is that current aquaculture practices are neither meeting the needs of fish nor environment. Thus, the obvious environmental and animal welfare aspects of finfish aquaculture make it hard to ethically defend a fish diet.  相似文献   
73.
'Molecular farming' is the production of valuable recombinant proteins in transgenic organisms on an agricultural scale. While plants have long been used as a source of medicinal compounds, molecular farming represents a novel source of molecular medicines, such as plasma proteins, enzymes, growth factors, vaccines and recombinant antibodies, whose medical benefits are understood at a molecular level. Until recently, the broad use of molecular medicines was limited because of the difficulty in producing these proteins outside animals or animal cell culture. The application of molecular biology and plant biotechnology in the 1990s showed that many molecular medicines or vaccines could be synthesised in plants and this technology is termed 'molecular farming'. It results in pharmaceuticals that are safer, easier to produce and less expensive than those produced in animals or microbial culture. An advantage of molecular farming lies in the ability to perform protein production on a massive scale using hectares of cultivated plants. These plants can then be harvested and transported using the agricultural infrastructure. Thus, molecular farming allows rapid progress from genetic engineering to crop production, and new cash crops producing recombinant proteins are already being commercially exploited. We speculate that as functional genomics teaches us more about the nature of disease, molecular farming will produce many of the protein therapeutics that can remedy it.  相似文献   
74.
This paper examines the legitimacy, viability and efficiency of the European Union Solidarity Fund by asking whether the Fund meets its stated purpose of providing solidarity within the EU, whether it is sufficiently capitalized and if it promotes disaster risk reduction in Europe. In examining these questions, we make use of ADAM models of disaster risks throughout Europe. We conclude that the Solidarity Fund falls short on all three counts, and we suggest possible alternatives. Most far-reaching, we explore whether the EUSF could support insurance systems in Europe by, among other possible activities, capitalizing national public-private insurance programs and providing support for government risk transfer. This would leverage the Fund’s capital and would overcome barriers to the provision of private and public sector insurance in uncertain catastrophe markets. It would also make insurance more affordable to Europe’s most vulnerable communities. Finally, it would reduce the disincentives for risk reduction inherent in post-disaster assistance.  相似文献   
75.
76.
Honeybee colonies (Apis mellifera) maintain temperatures of 35-36°C in their brood nest because the brood needs high and constant temperature conditions for optimal development. We show that incubation of the brood at the level of individual honeybees is done by worker bees performing a particular and not yet specified behaviour: such bees raise the brood temperature by pressing their warm thoraces firmly onto caps under which the pupae develop. The bees stay motionless in a characteristic posture and have significantly higher thoracic temperatures than bees not assuming this posture in the brood area. The surface of the brood caps against which warm bees had pressed their thorax were up to 3.2°C warmer than the surrounding area, confirming that effective thermal transfer had taken place.  相似文献   
77.
Anthropogenic processes have increased the exposure of humans and wildlife to toxic methyl mercury (MeHg). Mercury emissions will increase by about 25% between 2005 and 2020, if the present trajectory is maintained. A global assessment of societal damages caused by the ingestion of methyl mercury, based merely on loss of IQ (Intelligence Quotient), suggests that the annual cost will be approximately US$3.7 billion (2005 dollars) in 2020. The corresponding cost of damages resulting from the inhalation of methyl mercury is estimated at US$2.9 million (2005 dollars). Under a higher degree of emission control such as in the case of the Extended Emission Control (EXEC) and the Maximum Feasible Technological Reduction (MFTR) scenarios, total emissions could decrease in the period 2005–2020 by about 50–60%. The corresponding annual benefits in 2020 are estimated to be about US$1.8–2.2 billion (2005 dollars). Large economic benefits can be achieved by reducing global mercury emissions.  相似文献   
78.
Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd.  相似文献   
79.
Both body mass and surface area are factors determining the essence of any living organism. This should also hold true for an extinct organism such as a dinosaur. The present report discusses the use of a new 3D laser scanner method to establish body masses and surface areas of an Asian elephant (Zoological Museum of Copenhagen, Denmark) and of Plateosaurus engelhardti, a prosauropod from the Upper Triassic, exhibited at the Paleontological Museum in Tübingen (Germany). This method was used to study the effect that slight changes in body shape had on body mass for P. engelhardti. It was established that body volumes varied between 0.79 m3 (slim version) and 1.14 m3 (robust version), resulting in a presumable body mass of 630 and 912 kg, respectively. The total body surface areas ranged between 8.8 and 10.2 m2, of which, in both reconstructions of P. engelhardti, ∼33% account for the thorax area alone. The main difference between the two models is in the tail and hind limb reconstruction. The tail of the slim version has a surface area of 1.98 m2, whereas that of the robust version has a surface area of 2.73 m2. The body volumes calculated for the slim version were as follows: head 0.006 m3, neck 0.016 m3, fore limbs 0.020 m3, hind limbs 0.08 m3, thoracic cavity 0.533 m3, and tail 0.136 m3. For the robust model, the following volumes were established: 0.01 m3 head, neck 0.026 m3, fore limbs 0.025 m3, hind limbs 0.18 m3, thoracic cavity 0.616 m3, and finally, tail 0.28 m3. Based on these body volumes, scaling equations were used to assess the size that the organs of this extinct dinosaur have.  相似文献   
80.
Terrestrial salamanders of the genus Salamandra represent one of the most prominent groups of amphibians. They are mainly distributed across Europe but also reach Northern Africa and the Near East. Members of the six currently accepted species have long been known to be poisonous; however, work on their toxins was mostly published in German language, and therefore, many nuances of these studies have remained hidden from the majority of herpetologists and toxinologists. Several Salamandra species are called fire salamanders due to their highly contrasted, black-yellow colouration which probably serves to deter predators, although thorough evidence for aposematism in Salamandra is still lacking. Salamandra skin toxins do not only represent a potent antipredator defence but may also have antimicrobial effects. A better understanding of this dual function of Salamandra skin secretions is of utmost importance in the face of the emergence of a fungal disease causing catastrophic declines of fire salamanders in Central Europe, caused by the fungus Batrachochytrium salamandrivorans. In this review, we summarize the knowledge on Salamandra toxins, providing a list of the compounds so far isolated from their secretion and focusing on the bioactivity of the major compounds in Salamandra secretions, the steroidal alkaloids. We identify priorities for future research, including a screening of co-occurrence of steroidal alkaloids and tetrodotoxins in salamandrids, chemical characterization of already identified novel steroidal compounds, elucidation of the presence and role of peptides and proteins in the secretion, and experimental in vitro and in vivo study of the interactions between bioactive compounds in Salamandra skin secretions and cutaneous fungal and bacterial pathogens.  相似文献   
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