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Definition of the problem The central focus of Empirical Ethics is the study of the social and cultural aspects inherent in medical practice. Arguments This approach distinguishes between the scientific-cognitive aspects and the cultural-normative aspects of medicine, which would conventionally be investigated separately by the social sciences. When however medicine is conceived of as social practice, the sharp distinction between scientific medicine, culturally normative aspects and ethical reflection becomes less distinct. Conclusion We suggest combining ethical reflection and empirical research in multiple stages. In this case, social scientific analyses would provide an initial framework for understanding medical practices and a foundation for further ethical investigations, which would then allow for a sociological critique. 相似文献
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Determination of selected organophosphate esters in the aquatic environment of Austria 总被引:1,自引:0,他引:1
Martínez-Carballo E González-Barreiro C Sitka A Scharf S Gans O 《The Science of the total environment》2007,388(1-3):290-299
Organophosphate esters are used in multitude of applications such as flame retardants, plasticizers and lubricants. In recent years concerns have been raised in regards to the environmental impact of some of the more commonly used phosphoric acid triesters, because many of them are toxic and persistent. Liquid-liquid extraction and ultrasound-assisted solvent extraction followed by liquid chromatography coupled to tandem mass spectrometry detection (LC-MS/MS) were used for the determination of nine priority organophosphate esters in waste and surface water, as well as in sediment samples for first time in Austria. Recoveries ranged from 63% to 94% in water and from 74 to 104% in sediment with estimated quantification limits between 2.6 and 7.9 ng/l in surface water, 4.1 and 13 ng/l in effluent waste water, and between 0.48 and 11 microg/kg in sediment. The validated method was applied to determine the occurrence of the selected organophosphorus flame retardants (OPFRs) and plasticizers in the aquatic environment of Austria. The impact of the discharge of waste water treatment plants into the receiving water bodies was also studied. 相似文献
76.
S Berg A Rønnekleiv 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2012,59(7):1537-1549
Capacitive micromachined ultrasonic transducers (CMUTs) have shown promising qualities for medical imaging. However, there are still some problems to be investigated, and some challenges to overcome. Acoustic backing is necessary to prevent SAWs excited in the surface of the silicon substrate from affecting the transmit pattern from the array. In addition, echoes resulting from bulk waves in the substrate must be removed. There is growing interest in integrating electronic circuits to do some of the beamforming directly below the transducer array. This may be easier to achieve for CMUTs than for traditional piezoelectric transducers. We will present simulations showing that the thickness of the silicon substrate and thicknesses and acoustic properties of the bonding material must be considered, especially when designing highfrequency transducers. Through simulations, we compare the acoustic properties of 3-D stacks bonded with three different bonding techniques; solid-liquid interdiffusion (SLID) bonding, direct fusion bonding, and anisotropic conductive adhesives (ACA). We look at a CMUT array with a center frequency of 30 MHz and three silicon wafers underneath, having a total silicon thickness of 100 μm. We find that fusion bonding is most beneficial if we want to prevent surface waves from damaging the array response, but SLID and ACA are also promising if bonding layer thicknesses can be reduced. 相似文献
77.
Gleich zwei neue Wege beschreitet der VwGH bei der Auslegung des § 25 Abs 3 sbg BGG aus Anlass eines Beschwerdeverfahrens.
Einerseits zieht er mittels einer auch dem Gleichheitsgrundsatz Rechnung tragenden systematischen Interpretation § 33 Abs
3 sbg ROG 1998 – eine an sich für die Bebauungsplanung geltende Norm – für die Frage der Abstandsrelevanz von Giebelbereichen
bei anderen "nicht traditionellen" Dachformen als Satteld?chern heran. Dies zu Recht, wie die Autoren meinen. Andererseits
versucht der VwGH, den Begriff des "natürlichen" bzw "gewachsenen" Gel?ndes nach dem sbg BGG zu konkretisieren und findet
dafür eine L?sung im Inkrafttretenszeitpunkt des sbg BGG, quasi als "Versteinerungszeitpunkt". Letzteres vermag die Autoren
nicht zu überzeugen. 相似文献
78.
Erwann Lagabrielle Aurélie Botta Williams Daré Daniel David Sigrid Aubert Christo Fabricius 《Environmental Modelling & Software》2010,25(11):1413-1427
This paper considers participatory modelling to integrate biodiversity conservation into land use planning and to facilitate the incorporation of ecological knowledge into public decision making for spatial planning. Réunion Island has experienced rapid urban and agricultural expansion, which threaten its unique biodiversity. In this context, we designed three participatory modelling sequences, involving overall 24 multidisciplinary researchers and stakeholders. The sequences aimed: (1) to map land-use and biodiversity, (2) to develop a conservation plan following systematic conservation planning principles using a spatial optimization tool (MARXAN) and (3) to simulate coupled land-use/conservation scenarios using a multi-agent system (MAS). The conservation plan confirms that priority areas for biodiversity protection are located on the coast where rapid land-use changes occur. Nevertheless, stakeholders from the urban and agricultural sector did not participate to this sequence. Indeed, conservation planning tools are useful to locate conservation priorities but they have to be designed with stakeholders to be accepted as negotiation tool. Besides, the researchers engaged in this second sequence were perceived as conservation stakeholders rather than holders of scientific knowledge. In the third sequence, the researchers involved adopted the stance of facilitating the elicitation of each stake and gathered trust from stakeholders. Overall, we conclude that the participatory development of land-use simulation models should be promoted to explore alternative scenarios for biodiversity conservation with stakeholders. In a situation of land-use conflict, a gradual and sequential participatory modelling approach should be implemented to fit into public decision-making processes. 相似文献
79.
Yasaman Pakdaman Siren Berland Helene J. Bustad Sigrid Erdal Bryony A. Thompson Paul A. James Kjersti N. Power Stle Ellingsen Martin Krooni Line I. Berge Adrienne Sexton Laurence A. Bindoff Per M. Knappskog Stefan Johansson Ingvild Aukrust 《International journal of molecular sciences》2021,22(11)
Variants in STUB1 cause both autosomal recessive (SCAR16) and dominant (SCA48) spinocerebellar ataxia. Reports from 18 STUB1 variants causing SCA48 show that the clinical picture includes later-onset ataxia with a cerebellar cognitive affective syndrome and varying clinical overlap with SCAR16. However, little is known about the molecular properties of dominant STUB1 variants. Here, we describe three SCA48 families with novel, dominantly inherited STUB1 variants (p.Arg51_Ile53delinsProAla, p.Lys143_Trp147del, and p.Gly249Val). All the patients developed symptoms from 30 years of age or later, all had cerebellar atrophy, and 4 had cognitive/psychiatric phenotypes. Investigation of the structural and functional consequences of the recombinant C-terminus of HSC70-interacting protein (CHIP) variants was performed in vitro using ubiquitin ligase activity assay, circular dichroism assay and native polyacrylamide gel electrophoresis. These studies revealed that dominantly and recessively inherited STUB1 variants showed similar biochemical defects, including impaired ubiquitin ligase activity and altered oligomerization properties of the CHIP. Our findings expand the molecular understanding of SCA48 but also mean that assumptions concerning unaffected carriers of recessive STUB1 variants in SCAR16 families must be re-evaluated. More investigations are needed to verify the disease status of SCAR16 heterozygotes and elucidate the molecular relationship between SCA48 and SCAR16 diseases. 相似文献
80.
Beiboer Sigrid H.W.; Berg Bert van den; Dekker Niek; Cox Ruud C.; Verheij Hubertus M. 《Protein engineering, design & selection : PEDS》1996,9(4):345-352
The effect of the substitution of the active site histidine48 by the unnatural 1,2,4-triazole-3-alanine (TAA) amino acidanalogue in porcine pancreas phospholipase A2 (PLA2) was studied.TAA was introduced biosynthetically using a his-auxotrophicEscherichia coli strain. To study solely the effect of the substitutionof the active site histidine, two nonessential histidines (i.e.His17 and His 115) were replaced by asparagines, resulting ina fully active mutant enzyme (His-PLA2). In this His-PLA2 thesingle histidine at position 48 was substituted by TAA withan incorporation efficiency of about 90%, giving a mixture ofHis-PLA2 and TAA-PLA2. Based on the charge difference at acidicpH, both forms could be separated by FPLC, allowing for thepurification of TAA-PLA2 free from His-PLA2. At pH 6, TAA-PLA2has a fivefold reduced activity compared with His-PLA2. Thisreduced activity paralells a reduced rate of covalent modificationwith p-nitrophenacyl bromide of TAA-PLA2 compared with His-PLA2.Competitive inhibition gave comparable IC50 values for WT-PLA2,His-PLA2 and TAA-PLA2. These results indicate that the reductionin activity is not caused by a different affinity for the substrate,but more likely results from a reduced kcat value in TAA-PLA2.The enzymatic activities for native and mutant PLA2s were measuredat different pH values. For WT-PLA2 and His-PLA2 the activityis optimal at pH 6 and is strongly deminished at acidic pH,with no observable activity at pH 3. In contrast, TAA-PLA2 isas active at pH 3 as at pH 6. Most likely, the decrease in activityobserved for WT-PLA2 and His-PLA2 is caused by the protonationof the active site His48, which is the general base involvedin the activation of the nucleophilic water molecule. In TAA-PLA2,however, the active site residue TAA48 is unprotonated at bothpH 3 and 6 as a result of the low pKa of TAA compared with histidine. 相似文献