Abnehmende Kooperation in der Umweltpolitik trotz zunehmender wirtschaftlicher Integration : das kanadisch-amerikanische Verhältnis im Umweltbereich

Over the last decades, Canada and Switzerland, countries with "small" economies, when compared with their neighbours, have experienced increasing economic Integration with their main trading partners, the United States and the European Community (EC) respectively. Using a political-economic approach, this article analyzes the effects of growmg Integration for management of transboundary, environmental problems in North America. As well, in view of the Canadian experience, possible implications for Switzerland in its future relationship to the EC are addressed.<br> In the past the Canadian-American debate over transboundary environmental problems has centered around questions of territory. Despite increasing economic Integration, the dominant reaction to ecological interdependence has been reliance on national policies. In accordance with the American, economic leadership in the continental System, the kind of political response to transboundary, environmental Problems is mainly dictated by the importance of the problem in the United States. The Great Lakes are an area of mutual concern and, therefore, an example for limited, environmental Cooperation and the adoption of an environmental advanced Position. In the U. S., the political response to acid rain was reactive and delayed, since only certain regions were concerned. Despite Canadian domestic and international efforts during the 1980s, until recently no significant progress has been made in developing effective measures to abate air emissions.<br> The conclusion of the Canada-U. S. Free Trade Agreement (FTA) in 1988 did not change the very nature of the mutual environmental relationship. However, in the corollary to the FTA serious threats to the environment can be identified. Liberalized trade and restrained State Intervention foster the accelerated exploitation of Canada's natural resources and further the harmonization of environmental Standards between the two countries.<br> In view ofthe Canadian experience, the article concludes that for Switzerland an economic agreement with the EC without parallel environmental commitments could have significant, negative consequences

Epidermal or dermal specific knockout of PHD-2 enhances wound healing and minimizes ischemic injury.

INTRODUCTION:Hypoxia-inducible factor (HIF)-1α, part of the heterodimeric transcription factor that mediates the cellular response to hypoxia, is critical for the expression of multiple angiogenic growth factors, cell motility, and the recruitment of endothelial progenitor cells. Inhibition of the oxygen-dependent negative regulator of HIF-1α, prolyl hydroxylase domain-2 (PHD-2), leads to increased HIF-1α and mimics various cellular and physiological responses to hypoxia. The roles of PHD-2 in the epidermis and dermis have not been clearly defined in wound healing. METHODS:Epidermal and dermal specific PHD-2 knockout (KO) mice were developed in a C57BL/6J (wild type) background by crossing homozygous floxed PHD-2 mice with heterozygous K14-Cre mice and heterozygous Col1A2-Cre-ER mice to get homozygous floxed PHD-2/heterozygous K14-Cre and homozygous floxed PHD-2/heterozygous floxed Col1A2-Cre-ER mice, respectively. Ten to twelve-week-old PHD-2 KO and wild type (WT) mice were subjected to wounding and ischemic pedicle flap model. The amount of healing was grossly quantified with ImageJ software. Western blot and qRT-PCR was run on protein and RNA from primary cells cultured in vitro. RESULTS:qRT-PCR demonstrated a significant decrease of PHD-2 in keratinocytes and fibroblasts derived from tissue specific KO mice relative to control mice (*p<0.05). Western blot analysis showed a significant increase in HIF-1α and VEGF protein levels in PHD-2 KO mice relative to control mice (*p<0.05). PHD-2 KO mice showed significantly accelerated wound closure relative to WT (*p<0.05). When ischemia was analyzed at day nine post-surgery in a flap model, the PHD-2 tissue specific knockout mice showed significantly more viable flaps than WT (*p<0.05). CONCLUSIONS:PHD-2 plays a significant role in the rates of wound healing and response to ischemic insult in mice. Further exploration shows PHD-2 KO increases cellular levels of HIF-1α and this increase leads to the transcription of downstream angiogenic factors such as VEGF

The influence of human exploration on the microbial community structure and ammonia oxidizing potential of the Su Bentu limestone cave in Sardinia, Italy

The bacterial diversity in the Su Bentu Cave in Sardinia was investigated by means of 16S rRNA gene-based analysis. This 15 km long cave, carved in Jurassic limestone, hosts a variety of calcite speleothems, and a long succession of subterranean lakes with mixed granite and carbonate sands. The lower level is occasionally flooded by a rising groundwater level, but with only scarce input of organic remains (leaves and charcoal fragments). On the quiet cave pools there are visible calcite rafts, whereas walls are locally coated with manganese deposits. In the drier upper levels, where organic input is much more subdued, moonmilk—a hydrated calcium-magnesium carbonate speleothem—can be found. Relative humidity approaches 100% and the measured mean annual cave air temperature is 14.8°C. Samples were obtained in 2014 from calcite rafts, moonmilk, manganese oxide deposits and soil (limestone and granite grains). Microclimatic conditions in the cave near the sampling sites, sample properties, physico-chemical parameters of water, and sediment composition were determined. The microbial community of this system is predominately composed of the phyla Proteobacteria, Actinobacteria, Acidobacteria, Nitrospirae, and Firmicutes. Sampling sites near the entrance of the cave and in close proximity of the underground campsite–located 500 meters deep into the cave—revealed the highest diversity as well as the highest number of human associated microorganisms. Two samples obtained in very close proximity of each other near the campsite, indicate that the human impact is localized and is not distributed freely within the system. Analysis of the abundance of bacterial and archaeal amoA genes revealed a far greater abundance of archaeal amoA genes compared to bacterial representatives. The results of this study highlight that human impact is confined to locations that are utilized as campsites and that exploration leaves little microbial trails. Furthermore, we uncovered a highly specialized microbiome, which is perfectly adapted to survive and thrive in an environment with low nutrient availability

<i>In vivo</i> data from ischemic pedicle flap model.

<p><b>A</b>) Schematic of ischemic pedicle flap model. <b>B</b>) Representative figures taken at day 0 and 9 of ischemic flaps for wild type, heterozygous K14-Cre/homozygous floxed PHD-2, and heterozygous Col1α2-Cre-ER/homozygous floxed PHD-2 mice. A schematic of tissue reperfusion gradient is also shown. <b>C</b>) Graphical representation of total flap ischemia with a significant difference (*p<0.05) between the wild type and the heterozygous K14-Cre/homozygous floxed PHD-2, and heterozygous Col1α2-Cre-ER/homozygous floxed PHD-2 mice.</p

<i>In vivo</i> data from humanized wound healing model.

<p><b>A</b>) Schematic of stented full-thickness excisional wound model. <b>B</b>) Representative pictures of wounds from days 0–14 for wild type, heterozygous K14-Cre/homozygous floxed PHD-2, and heterozygous Col1α2-Cre-ER/homozygous floxed PHD-2 mice. <b>C</b>) Twelve week wound healing curve showing the wound closure rate for wild type, heterozygous K14-Cre/homozygous floxed PHD-2, and heterozygous Col1α2-Cre-ER/homozygous floxed PHD-2 mice with significant differences on days 4, 6, and 8 (*p<0.05). <b>D</b>) Graph representing days to wound closure with a significant difference in days to closure between the wild type and the heterozygous K14-Cre/homozygous floxed PHD-2 and heterozygous Col1α2-Cre-ER/homozygous floxed PHD-2 mice (*p<0.05).</p

The fungal colonisation of rock-art caves: experimental evidence

The conservation of rock-art paintings in European caves is a matter of increasing interest. This derives from the bacterial colonisation of Altamira Cave, Spain and the recent fungal outbreak of Lascaux Cave, France—both included in the UNESCO World Heritage List. Here, we show direct evidence of a fungal colonisation of rock tablets in a testing system exposed in Altamira Cave. After 2 months, the tablets, previously sterilised, were heavily colonised by fungi and bacteria. Most fungi isolated were labelled as entomopathogens, while the bacteria were those regularly identified in the cave. Rock colonisation was probably promoted by the dissolved organic carbon supplied with the dripping and condensation waters and favoured by the displacement of aerosols towards the interior of the cave, which contributed to the dissemination of microorganisms. The role of arthropods in the dispersal of spores may also help in understanding fungal colonisation. This study evidences the fragility of rock-art caves and demonstrates that microorganisms can easily colonise bare rocks and materials introduced into the cavity