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991.

Definition of the problem

The role of stories is well established in the traditions of narrative ethics and casuistry. However, from a methodological point of view, the inclusion of fictional works in moral deliberation remains yet unanswered. The paper explains the potential of dystopias for bioethics by means of selected examples and a critical reconstruction and expansion of existing approaches.

Arguments

By means of literary theories, it is proposed to include moral beliefs that motivate dystopias in coherent reflection and reasoning procedures. Furthermore, dystopia’s potential through socioculturally dense scenarios, a contemporary-historical context, and a sensitization to the moral relevance of language for bioethical research are systematically presented.

Conclusion

The methodological considerations provide, on the one hand, practical points of reference for didactic approaches and, on the other hand, for public deliberation. However, the analysis also shows that dystopias introduce their own moral positions beyond a mere illustration or warning.
  相似文献   
992.

Definition of the problem

The central foundations of successful dental treatment consist of a trustful patient-dentist relationship, the professional and psychosocial expertise of the team treating the patient, and consideration of ethical aspects both during the therapeutic decision-making process and during the subsequent execution of therapy. This is especially true of the dental treatment of (mostly elder) persons with dementia, calling for an in-depth assessment of the various normative implications.

Arguments

In geriatric dentistry in particular, situational dilemmas regarding treatment often arise from specific constellations (e.?g. greatly reduced potential for dental therapy, lack of ability regarding oral hygiene and lack of individual patient responsibility) combined with an acute need for treatment and the necessary involvement of third parties. These dilemmas frequently place additional professional and normative demands on the dentist. The current contribution discusses this specific situation, first by way of theoretical discourse and subsequently with a case-related approach on the basis of two case histories.

Conclusion

It becomes clear here that classic state-of-the-art therapies are replaced by “compromise treatment” in many cases in geriatric dentistry. Such treatment follows divergent diagnostic and therapeutic rules, poses changed requirements in terms of communication and presents specific ethical challenges and pitfalls.
  相似文献   
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In order to establish a simple, sensitive, and fast reliable detection method to determine the magnolol, FeWO4 nanoflower was synthesised through a solvothermal technique and FeWO4 nanoflower modified carbon paste electrode (CPE) was developed. The voltammetric behavior of magnolol on the modified electrodes was studied using cyclic voltammetry (CV), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV). The experimental results showed that the modified electrode remarkably enhanced the electrochemical response of the magnolol and exhibited a wide linear range for determination of the magnolol from 1.0×10-7 to 1.0×10-4 mol/L with a low detection limit of 5.0×10-8 mol/L.  相似文献   
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A new corona protection varnish was prepared by using epoxy/montmorillonite nano-composite and pure epoxy resin as adhesives respectively. The adhesive with different amounts of organic montmorillonite (OMMT) was mixed with 1200 mesh silicon carbide (SiC) by different weight ratios. The surface states of the varnishes with various adhesives were observed by powerful optical microscope. Some properties of the varnishes were analyzed during the enduring time under 5kV/cm DC, such as the relation of change in nonlinear coefficient, natural surface resistivity, and surface temperature variation. The results showed that the amounts of OMMT had little effect on the natural surface resistance of the varnish but had important influence on the nonlinear property of the varnish. When the range of the OMMT content was 2wt% to 6wt%, the nonlinear coefficient of all materials with epoxy/OMMT nano-composite adhesive was higher than that with pure epoxy resin adhesive. The surface temperature of the varnish with epoxy/OMMT nanocomposite adhesive was all lower than that with the pure epoxy resin adhesive under high electrical field strength.  相似文献   
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Influence of aluminum addition on the structures and properties of SiO2-B2O3-Al2O3-CaO vitrified bond at low sintering temperature and high strength was discussed. FTIR and XRD analyses were used to characterize the structures of the basic vitrified bond with different contents of aluminum. The bending strength and the thermal expansion coefficients were also tested. Meanwhile, the microstructures of composite specimens at sintering temperature of 660 °C were observed by scanning electron microscope (SEM). The experimental results showed that the properties of vitrified bond with 1wt% aluminum were improved significantly, where the bending strength, Rockwell hardness, and thermal expansion coefficient of the vitrified bond reached 132 MPa, 63 HRB, and 6.73×10-6 °C-1, respectively.  相似文献   
1000.
Any shortfall in the required depth during milling machining can affect the dimensional accuracy of the part produced and can cause a catastrophic failure to the machine. Corrective remedies to fix the dimensions inaccuracy will increase the machining time and costs. In this work, a depth-of-cut monitoring system was proposed to detect depth of cut in real time using an acoustic emission sensor and prediction model. The characteristics of the sensor signal obtained in machining processes can be complex in terms of both nonlinearity and nonstationarity. To overcome this complexity, a regression model and an artificial neural network model were used to represent the relationship between the acoustic emission signal and the depth of cut. The model was tested under different machining cases and found to be efficient in predicting the depth of cut.  相似文献   
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