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11.
BACKGROUND: During the 9 months between July, 1996, and March, 1997, the provision of euthanasia for the terminally ill was legal in the Northern Territory of Australia. Seven patients made formal use of the Rights of the Terminally Ill (ROTI) Act; four died under the Act. We report their clinical details and the decision-making process required by the Act. METHODS: We taped in-depth interviews with the general practitioner who provided euthanasia. Further information was available from public texts created by patients, the media, and the coroner. FINDINGS: All seven patients had cancer, most at advanced stages. Three were socially isolated. Symptoms of depression were common. Having met criteria of the Act, some patients deferred their decision for a time before proceeding with euthanasia. Medical opinions about the terminal nature of illness differed. INTERPRETATION: Provision of opinions about the terminal nature of illness and the mental health of the patient, as required by the ROTI Act, created problematic gatekeeping roles for the doctors involved.  相似文献   
12.
Tumour formation relies on a complex combination of genetic and environmental factors. In particular, the contributions from inherited predisposition genes as well as carcinogens, for example from cigarettes or in the diet, are amongst the major contributors to tumorigenesis. Since the study of such processes in particularly difficult in human cancers, the availability of a well-defined model system is of obvious benefit. The mouse skin model of multistage carcinogenesis offers an excellent tool for the study of the target cells, the target genes and the biological events associated with neoplasia. In this system, tumorigenesis occurs in a series of defined stages, each of which is characterized by specific and reproducible alterations in genes such as H-ras, cyclin D1, p53 and p16INK4A. Additional changes occur in the production of, or response to, factors such as transforming growth factor beta (TGF beta). These genetic and biological alterations are mirrored in human tumours of epithelial origin. Hence, research into the general principles of tumour initiation, promotion and progression in the context of the mouse skin model is likely to prove valuable in the continual search for new methods for the diagnosis, prevention, and therapeutic treatment of human cancers.  相似文献   
13.
Abstract— A non‐contact jet‐printed mask‐patterning process is described. By combining digital imaging with jet printing, digital lithography was used to pattern a‐Si:H‐based electronics on glass and plastic substrates in place of conventional photolithography. This digital lithographic process is capable of layer‐to‐layer registration of ±5 μm using electronic mask files that are directly jet printed onto a surface. Aminimum feature size of 50 μm was used to create 180 × 180 element backplanes having 75‐dpi resolution for display and image‐sensor applications. By using a secondary mask process, the minimum feature size can be reduced down to ~15 μm for fabrication of short‐channel thin‐film transistors. The same process was also used to pattern black‐matrix wells in fabricating color‐filter top plates in LCD panels.  相似文献   
14.
Abstract— Methods used to deposit and integrate solution‐processed materials to fabricate TFT backplanes by ink‐jet printing are discussed. Thematerials studied allow the development of an all‐additive process in which materials are deposited only where their functionality is required. The metal layer and semiconductor are printed, and the solution‐processed dielectric is spin‐coated. Silver nanoparticles are used as gate and datametals, the semiconductor used is a polythiophene derivative (PQT‐12), and the gate dielectric is an epoxy‐based photopolymer. The maximum processing temperature used is 150°C, making the process compatible with flexible substrates. The ION/IOFF ratio was found to be about 105?106, and TFT mobilities of 0.04 cm2/V‐sec were obtained. The influence of surface treatments on the size and shape of printed features is presented. It is shown that coffee‐stain effects can be controlled with ink formulation and that devices show the expected pixel response.  相似文献   
15.
16.
Materials science is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This scientific field investigates the relation-ship between the structure of materials at atomic or mo-  相似文献   
17.
SNS的品牌传播成功要素浅析   总被引:1,自引:0,他引:1  
文章在分析了SNS的概念与特点的基础上,简要探讨了SNS品牌传播成功的要素。  相似文献   
18.
Ionic liquids are a class of salts that incorporate polyatomic anions and cations. These materials are typically viscous fluids at room temperature. The fluids are generally characterized as possessing negligible vapor pressures under ambient conditions. These beneficial properties have led us to study the effectiveness of ionic liquids containing both organic cations and anions for use as lubricants with space applications. This article presents vapor pressure measurements for four ionic liquids as well as friction coefficient data from a spiral orbit tribometer in the boundary lubrication regime under simulated space conditions using stainless steel tribocouples. In addition, we present the first tribological data on mixed ionic liquids and an ionic liquid additive. Postmortem infrared and Raman analyses of the balls and races indicates that the major degradation pathway for these organic ionic liquids is similar to those of other carbon-based liquid lubricants; that is, deterioration of the organic structure into amorphous graphitic carbon. The coefficients of friction and lifetimes of these lubricants are comparable to or better than those of several commonly used space oils.  相似文献   
19.
Objective: The authors conducted a meta-analysis of empirical studies investigating associations between indices of posttraumatic stress disorder (PTSD) and intimate relationship problems to empirically synthesize this literature. Method: A literature search using PsycINFO, Medline, Published International Literature on Traumatic Stress (PILOTS), and Dissertation Abstracts was performed. The authors identified 31 studies meeting inclusion criteria. Results: True score correlations (ρ) revealed medium-sized associations between PTSD and intimate relationship discord (ρ = .38, N = 7,973, K = 21), intimate relationship physical aggression perpetration (ρ = .42, N = 4,630, K = 19), and intimate relationship psychological aggression perpetration (ρ = .36, N = 1,501, K = 10). The strength of the association between PTSD and relationship discord was higher in military (vs. civilian) samples, and when the study was conducted in the United States (vs. other country), and the study represented a doctoral dissertation (vs. published article). The strength of the association between PTSD and physical aggression was higher in military (vs. civilian) samples, males (vs. females), community (vs. clinical) samples, studies examining PTSD symptom severity (vs. diagnosis), when the physical aggression measure focused exclusively on severe violence (vs. a more inclusive measure), and the study was published (vs. dissertation). For the PTSD–psychological aggression association, 98% of the variance was accounted for by methodological artifacts such as sampling and measurement error; consequently, no moderators were examined in this relationship. Conclusions: Findings highlight a need for the examination of models explaining the relationship difficulties associated with PTSD symptomatology and interventions designed to treat problems in both areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
A total of 29 tea samples of different origin, 13 green tea samples, 13 black tea samples, two semi-fermented and one white tea, imported to the Czech Republic, were collected and analysed for total content of aluminium (Al) in tea leaves and tea infusions, as well as for Al compounds in these infusions. The total content of metals in tea leaves differs according to the type of tea (green or black) and is probably influenced by many factors, e.g., soil properties. The HPLC/IC speciation of Al in tea infusions was performed for all samples. The addition of Al3+ to the tea infusion proved that Al3+, Al(Y)2+ and Al(X)1+ species can be determined in tea infusions. Increased extraction time did not show any affect on Al speciation, neither did the addition of sugar. After the addition of lemon juice, the speciation changed in one sample of black tea and five samples of green tea. These findings suggest that lemon juice as an additive can significantly influence Al speciation in tea infusions.  相似文献   
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