Background Regulations on forgoing life-sustaining treatment (LST) have developed in Asian countries including Japan, Korea and Taiwan. However, other countries are relatively unaware of these due to the language barrier. This article aims to describe and compare the relevant regulatory frameworks, using the (more familiar) situation in England as a point of reference. We undertook literature reviews to ascertain the legal and regulatory positions on forgoing LST in Japan, Korea, Taiwan, and England. Main text Findings from a literature review are first presented to describe the development of the regulatory frameworks surrounding the option of forgoing LST in each country. Based on the findings from the four countries, we suggest five ethically important points, reflection on which should help to inform the further development of regulatory frameworks concerning end-of-life care in these countries and beyond. There should be reflection on: (1) the definition of – and reasons for defining – the ‘terminal stage’ and associated criteria for making such judgements; Korea and Taiwan limit forgoing LST to patients in this stage, but there are risks associated with defining this too narrowly or broadly; (2) foregoing LST for patients who are not in this stage, as is allowed in Japan and England, because here too there are areas of controversy, including (in England) whether the law in this area does enough to respect the autonomy of (now) incapacitated patients; (3) whether ‘foregoing’ LST should encompass withholding and withdrawing treatment; this is also an ethically disputed area, particularly in the Asian countries we examine; (4) the family’s role in end-of-life decision-making, particularly as, compared with England, the three Asian countries traditionally place a greater emphasis on families and communities than on individuals; and (5) decision-making with and for those incapacitated patients who lack families, surrogate decision-makers or ADs. Conclusion Comparison of, and reflection on, the different legal positions that obtain in Japan, Korea, Taiwan, and England should prove informative and we particularly invite reflection on five areas, in the hope the ensuing discussions will help to establish better end-of-life regulatory frameworks in these countries and elsewhere.

Stress thallium-201 myocardial distribution was quantitatively evaluated by emission transaxial tomography in 104 patients who underwent coronary arteriography. The initial uptake and percent washout of thallium were assessed by the circumferential profile curves of the three short-axis sections and one middle right anterior oblique long-axis section. This quantitative tomographic analysis showed abnormal distribution in all but two patients (98%) with coronary artery disease, whereas qualitative analysis showed abnormality in 76 of the patients (93%). Quantitative analysis showed better sensitivity (91%) for detecting involved coronary vessels than qualitative analysis (80%, p less than 0.01), especially in three vessel disease (82 versus 67%, p less than 0.05). For localization of individual vessel involvement, quantitative analysis showed high sensitivity (right coronary artery: 96%, left anterior descending artery: 90% and left circumflex artery: 88%) as compared with qualitative analysis (88, 83 and 63%, respectively, p less than 0.05), while similar specificity was observed (92% for quantitative and 93% for qualitative analyses). Furthermore, in the study of patients without infarction, myocardial segments supplied by coronary vessels with moderate stenosis (51 to 75%) revealed abnormality more often with quantitative (81%) than with qualitative (56%) analysis. Thus, quantitative analysis of stress thallium emission tomography provides improved sensitivity for the detection of diseased coronary vessels in patients with three vessel disease and those with moderate stenosis. It is a valuable technique for the evaluation of coronary artery disease.

Three-dimensional numerical calculations have been performed on liquid-metal magnetohydrodynamic (MHD) flow through a rectangular channel in the inlet region of the applied magnetic field, including a region upstream the magnetic field section. The continuity equation, the momentum equation including the Lorentz force term and the induction equation have been solved numerically. The induction equation is derived from Maxwell's equations and Ohm's law in electromagnetism. The discretization of the equations is carried out by the finite difference method, and the solution procedure follows the MAC method. Along the flow axis (i.e. the channel axis), the pressure decreases slightly as normal non-MHD flow, increases once, thereafter decreases sharply and finally decreases as fully-developed MHD flow. The sharp decrease in the pressure, resulting in a large pressure drop, in the inlet region is due to increase in the induced electric current in this region comparing with that in the fully-developed region. In the inlet region, the flow velocity distribution changes from a parabolic profile of a laminar non-MHD flow to a flat profile of a fully-developed MHD flow.

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Seven different transition metal oxides (TiO 2 , ZnO, V 2 O 5 , Fe 2 O 3 , Co 3 O 4 , MnO 2 , and CuO) have been investigated for oxidation of diesel particulate matter (PM) under plasma discharge conditions. The experiments were carried out by measuring PM oxidation rates over each catalyst using a batch-type dielectric barrier discharge reactor. It was found that TiO 2 , ZnO, V 2 O 5 , and Fe 2 O 3 can promote PM oxidation, among which Fe 2 O 3 is a most desirable catalyst for PM oxidative removal as PM oxidation rate promoted by Fe 2 O 3 is highest under plasma discharge conditions. The mechanism of PM catalytic oxidation over the metal oxides has been suggested to follow the redox catalytic cycles from the correlation of the catalytic oxidation rates with the formation enthalpies per oxygen atom of the catalysts. O atoms generated by plasma discharges may play an important role in promoting the re-oxidation of the catalysts. The highest catalytic activity for the PM oxidation with Fe 2 O 3 has been suggested to be due to the balance between the reduction rate and the reoxidation rate within the redox catalytic cycles.

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Self-healing materials that can spontaneously repair damage under mild conditions are desirable in many applications. Significant progress has recently been made in the design of polymer materials capable of healing cracks at the molecular scale using reversible bonds; however, such a self-healing mechanism has rarely been applied to rigid inorganic materials. Here, we demonstrate the self-healing ability of lamellar silica-based thin films formed by self-assembly of silica precursors and quaternary ammonium-type surfactants. Specifically, spontaneous healing of cracks (typically less than 1.5 μm in width) was achieved under humid conditions even at room temperature. The randomly oriented lamellar structure with thin silica layers is suggested to play an essential role in crack closure and the reformation of siloxane networks on the fracture surface. These findings will lead to the creation of smart self-healing silica-based materials based on reversible siloxane bonds.

To assess the value of myocardial-perfusion positron computed tomography (PCT) for the evaluation of coronary artery disease (CAD), 13N-ammonia PCT using a whole-body multislice PCT device was performed at rest and during exercise in 6 normal subjects and 19 patients with angiographically documented CAD. The 13N-ammonia distribution in the myocardium was assessed both qualitatively and quantitatively. At rest and during exercise, the tracer distribution was homogeneous in the 6 normal cases. In the 19 patients with CAD, regional hypoperfusion was observed in 14 cases (74%) at rest and in 18 cases (95%) during exercise. Additional perfusion abnormalities were detecting during exercise in 12 cases. Segmental analysis of the myocardial perfusion identified 30 out of 34 stenosed vessels (88%) during exercise, with only one false-positive finding of diseased vessels (specificity, 98%). For the quantitative analysis of myocardial perfusion by PCT, the percentage of change in the tracer concentration in the same region between the rest and stress images was calculated. The concentration was slightly increased in normal myocardial segments (14.4% +/- 5.8%; P less than 0.001), whereas in CAD, it was significantly decreased in segments with stenosed vessels (-18.0% +/- 18.3%; P less than 0.02). We conclude that 13N-ammonia PCT at rest and during exercise provides high-quality images, and is a sensitive and effective technique for detecting CAD and identifying individual stenosed vessels. Furthermore, this technique makes possible quantitative assessment of the coronary reserve function.