Bioethics for clinicians: 11. Euthanasia and assisted suicide

Euthanasia and assisted suicide involve taking deliberate action to end or assist in ending the life of another person on compassionate grounds. There is considerable disagreement about the acceptability of these acts and about whether they are ethically distinct from decisions to forgo life-sustaining treatment. Euthanasia and assisted suicide are punishable offences under Canadian criminal law, despite increasing public pressure for a more permissive policy. Some Canadian physicians would be willing to practise euthanasia and assisted suicide if these acts were legal. In practice, physicians must differentiate between respecting competent decisions to forgo treatment, providing appropriate palliative care, and acceeding to a request for euthanasia or assisted suicide. Physicians who believe that euthanasia and assisted suicide should be legally accepted in Canada should pursue their convictions only through legal and democratic means.     

Estimation of Concentration and Bonding Environment of Water Dissolved in Common Solvents Using Near Infrared Absorptivity

Integrated near infrared (NIR) absorbance has been used to determine the absorptivity of the υ₂ + υ₃ combination band of the asymmetric stretch (υ2) and the bending vibration (υ3) for water in several organic solvents. Absorptivity measured in this way is essentially constant across the absorption envelope and is found to be 336 L mol⁻¹ cm⁻¹ with a standard deviation of 4 L mol⁻¹ cm⁻¹ as estimated from a least squares fit of a straight line to data from water concentrations between 0.01 mol/L and 0.06 mol/L. Absorptivity measured from the peak maximum of the υ2 + υ3 combination band of water varies with the type of hydrogen bonding of the water molecule because the shape of the NIR absorption envelope changes with the hydrogen bonding.Because the integrated NIR absorptivity of the υ₂ + υ₃ combination band of water is essentially constant across the absorption envelope, the NIR absorption envelope reflects the distribution of hydrogen bonding of the water. The shape and location of the absorption envelope appear to be governed mostly by the number of hydrogen bonds from the water molecules to easily polarized atoms. Water that is a donor in hydrogen bonds to atoms which are not easily polarized (such as the oxygen of a typical carbonyl group) absorbs near 5240 cm⁻¹ to 5260 cm⁻¹. Water that donates one hydrogen bond to an easily polarized atom (such as a water molecule oxygen) absorbs near 5130 cm⁻¹ to 5175 cm⁻¹, and water that donates two hydrogen bonds to easily polarized atoms is estimated to absorb near 5000 cm⁻¹ to 5020 cm⁻¹. Water donating two hydrogen bonds to other water molecules may be said to be in a water-like environment. In no case does a small amount of water absorbed in a host material appear to have a water-like environment.     

Jet array driven flow on the nozzle plate of an inkjet printhead in deposition of molten nylon materials

During research into an inkjet-integrated manufacturing process, jetting of molten caprolactam was investigated using a piezoelectric drop-on-demand printhead. Due to the start-up purging step and the surface energy differences, a wetting melt layer on the printhead's nozzle plate was formed. With appropriate parameters, a stable jet array was made. However, contamination on the nozzle plate disturbed the jet stability resulting in jet trajectory errors and even jet failures. Particles were used to characterise the melt flow field on the nozzle plate during jetting when multiple nozzles were actuated. Particle tracking velocimetry revealed that movement of the particles followed a specific pattern when the jet array was developed. Flow pattern driven by an actuating nozzle influenced those of adjacent nozzles. The movement of particles towards and from the actuating nozzles was observed at the same time and position with velocities up to 2 mm/s. This showed that a complex flow system was generated on the nozzle plate during jetting with multiple nozzles which influenced the reliability of the inkjet printhead.     

Chemistry of Silanes: Interfaces in Dental Polymers and Composites

The performance and service life of glass-or ceramic-filled polymeric composites depend on the nature of their resin, filler and interfacial phases as well as the efficacy of the polymerization process. The synergy that exists between the organic polymer matrix and the usually inorganic reinforcing filler phase is principally mediated by the interfacial/interphasial phase. This latter phase develops as a result of the dual reactivity of a silane coupling agent, (YRSiX₃), a bifunctional molecule capable of reacting with the silanol groups of glass or ceramic fillers via its silane functional group (–SiX₃) to form Si-O-Si- bonds to filler surfaces, and also with the resin phase by graft copolymerization via its Y functional group, usually a methacrylic vinyl group. In this paper, we explore some of the chemistry of organosilanes, especially that of functional organosilanes (or silane coupling agents as they are commonly known) that are used to mediate interfacial bonding in mineral reinforced polymeric composites. The chemistry of organosilanes can be quite complex involving hydrolytically initiated self-condensation reactions in solvents (including monomers) that can culminate in polymeric silsesquioxane structures, exchange reactions with hydroxylated or carboxylated monomers to form silyl ethers and esters, as well as the formation of silane derived interfaces by adhesive coupling with siliceous mineral surfaces.     

Phase I pilot study of the effects of trovafloxacin (CP-99,219) on the pharmacokinetics of theophylline in healthy men

INTRODUCTION: We report on a cost-effective easy-access software developed for the functional integration of the clinical records and history of oncologic patients with the management of the Day Hospital of the Radiotherapy Department of the University Hospital A. Gemelli, in Rome. MATERIAL AND METHODS: The software was designed to archive the clinical records and history of oncologic patients and the relative chemotherapy, to manage the examination scheduling, to draw up nursing files with the planned therapy and to make statistical analyses of the department activity. Five forms are available: the patient form, recording patient data; the admission form, recording the type of therapy (e.g., chemotherapy, tests, medical examinations, etc.), the relative cost and chemotherapy protocol, detailing for instance the type of drug; the nursing file, detailing chemotherapy schedule and the dilution of each drug; the menu, to select and retrieve any record. The minimum configuration requires a 386 Intel CPU, 4 Mb RAM and 4 Mb free on the hard disk. The software is the File Maker Pro 2.1 for Windows which can interact with Apple Macintosh computers. RESULTS: Since October, 1995, we have saved the clinical records of 272 oncologic outpatients (2415 entries in all), with a mean of 201/month. This computer system permitted us to save and retrieve data for both clinical and didactic purposes and to plan our activity. CONCLUSIONS: One year after it was implemented and used in clinical practice, the system is a cost-effective and user-friendly tool for the management of the Radiochemotherapy Day Hospital of our Radiotherapy Department.     

Human research beyond the medical model: legal and ethical issues

The diagnosis and treatment of adnexal cancers continues to pose a challenge to a wide range of clinicians. The diseases are a diverse lot, owing to the wide range of skin structures and large surface area. Early recognition and treatment are key to improved outcomes. Education of the patients as to their role in their care, especially early detection, is also of crucial importance. Further study may yield information to improve diagnosis and treatment.     

The fire performance of PVC

The role of PVC in fires is currently a controversial topic because of the many negative comments made about PVC on the occurrence of any major fire disaster. Critics also use many small-scale smoke and toxic gas tests to define the role of PVC in these fires. The purposes of this paper are (1) to summarize the current technical knowledge of real fire behavior, (2) use this understanding to interpret available data for PVC in large- and small-scale fire tests, and (3) help bring a sense of technical realism to the issues involved.     

Perceived control in the college classroom: Response–outcome contingency training and instructor expressiveness effects on student achievement and causal attributions.

Following an incentive (low, high) manipulation, 296 college students received response–outcome contingency training involving contingent, noncontingent, or no feedback and responded to an attribution questionnaire. All Ss then observed a lecture presented by a low- or high-expressive instructor and completed a postlecture achievement test and an attribution questionnaire. Results show that noncontingent Ss perceived less control and also manifested a helplessness attribution profile after the contingency manipulation. Postlecture results indicate that the high- compared to the low-expressive instructor increased achievement and internal locus in contingent but not noncontingent Ss for low-incentive conditions only. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydrogen molybdenum bronzes

Hydrogen molybdenum bronzes H_xMoO₃(0.3 <x<2.0) have been synthesised and characterised. Neutron diffraction studies with D_0.36MoO₃ confirm that D is incorporated as-OD with only a'ininor perturbation of the M0O₃ layer lattice. Hydrogen nobility in H_xMoO₃ has been studied by pulsed N.M.R.     

Die spektrometrische Untersuchung von Roheisen und Stählen mit geringen Kohlenstoff- und Mangangehalten

Bedeutung der Roheisenuntersuchung. Probenahme und -Vorbereitung. Versuchsdurchführung und endgültige Arbeitsbedingungen. Korrekturen. Programmanwahl mit Hilfe des Rechners. Aufstellen der Auswertekurve. Analysengenauigkeit. Grundsätzliche Schwierigkeiten bei der Bestimmung kleiner Gehalte. Erweiterung und Verlagerung der Meßbereiche. Einstellung des Rechners. Genauigkeit der Bestimmung.