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61.
Guidelines of good clinical practice regulate controlled clinical studies. Goal of the study, type of treatment and possible side effects have to be explained. The physician faces problems, if the study includes a "no treatment group". Referring to the literature and based on our own experience with tumor patients, several criteria are proposed to optimize the recruitment of patients. Important points are: Explanations should be given by an experienced doctor. He must be informed about the study and therapeutic alternative treatments. The atmosphere for the talk must be quiet. The participation of a person whom the patient trusts is desirable. The necessity of the study must be explained. Randomization in different study groups should be discussed without any preference. Prognosis should be explained without any detailed statistical data. Form of treatment, possible side effects and control examinations have to be discussed. The family physician's cooperation should be stressed. Personal autonomy in the patient's decision to participate in the study must be emphasized. Enough time for reflection must be granted before the final decision. It must be assured that the patient receives the same medical attention even after rejecting the study. These recommendations might help to avoid major mistakes which are harmful for the doctor-patient-relationship and further tumor therapy. A good initial discussion forms the basis for effective cooperation during tumor treatment. It may counteract the personal fear and negative reports in media of being "a guinea pig". The patient will appreciate the efforts of the doctor to provide optimal therapy. Furthermore, he will realize that such studies are necessary to improve future therapies. 相似文献
62.
Xu Sugang Yoshikane Noboru Shiraiwa Masaki Tsuritani Takehiro Zhang Xiaocheng Awaji Yoshinari Wada Naoya 《Photonic Network Communications》2020,40(3):175-193
Photonic Network Communications - To achieve fast recovery of optical transport networks after a disaster, we investigate a novel scheme enabling cooperation between carriers. Carriers can take... 相似文献
63.
A calcium phosphate glass-ceramic crown for dentistry was developed. The glass is cast into the shape of the crown by the lost-wax technique and subsequently heat-treated to convert it into the glass-ceramic, which exhibits excellent mechanical strength. The fine structure of the glass-ceramic is similar to that of the enamel of a natural tooth, and its hardness is near that of enamel. 相似文献
64.
Haruhisa Akiyama Tamaki Fukata Aishi Yamashita Masaru Yoshida Hideyuki Kihara 《The Journal of Adhesion》2017,93(10):823-830
ABSTRACTA reversible isothermal phase transition between the liquid and solid states in response to light irradiation was achieved in side chain-type azobenzene polymers. These materials can be used as adhesives that are detachable without applying any mechanical and thermal stress but also repeatedly reworkable because of their photoinduced liquefaction and solidification properties. The adhesive strength to glass plates was more than 3 MPa in single lap shear tests. This value is three times higher than previously reported and is sufficiently strong for glass substrates. 相似文献
65.
In recent years, the development of CAE (Computer Aided Engineering) in polymer processing has been remarkable, and it is expected to be more realistic in viscoelastic numerical simulation, particularly in three-dimensional complex geometry. Because of the problems of computational memory capacity, CPU time, and the numerical convergence of viscoelastic flow simulation, three-dimensional viscoelastic simulation applicable to industrial flow behaviors has not yet been attempted. In this paper, we developed the numerical simulation of three-dimensional viscoelastic flow within dies using a decoupled method, streamwise integration, and penalty function methods to decrease memory, and the TME (“Transformation of Equation of Motion to the Elliptic Equation,” S. Tanoue, T. Kajiwara, and K. Funatsu, The Eleventh Annual Meeting, the Polymer Processing Society Seoul, Korea, Extended Abstracts p.439) method, which raises the stability of convergence. We confirmed the reliability of this simulation technique to compare simulation results with experimental data of the stress field at a downstream wall shear rate of 5.41s?1 within a 60° angle tapered contraction die. We compared the predictions of a viscoelastic model (Phan-Thien and Tanner model) with a pure viscosity model (Carreau model) at a downstream wall shear rate of 120s?1 and discovered a remarkable effect of viscoelasticity in the shear stress and first normal stress difference in particular in the tapered region. 相似文献
66.
Takehiro Kaneko Yasuhiro Watanuki Takeshi Toyama Yoshiyuki Kojima Nobuyuki Nishimiya 《International Journal of Hydrogen Energy》2017,42(15):10014-10022
In order to enhance hydrogen storage capacity of carbonaceous materials through metal modification, FeNiCr-carbon composites were prepared by calcination of Fe, Ni and Cr-containing polyacrylonitrile (PAN) fibers fabricated by electrospinning method. Fe (III), Ni (II) and Cr (III) acetylacetonates (M (acac)n) were selected as metal sources. Increase of specific surface area and formation of micropores were observed on heat decomposition of M (acac)n particularly through introduction of steam. Maximal hydrogen content, 1.62 mass%, was obtained at 77 K under 0.8 MPa of hydrogen for a FeNiCr-carbon composite, which contained about 15.5 mass% of metals and had specific surface area of 501 m2 g?1. The hydrogen content exceeded the hydrogen physisorption limit, 2.34 mass% per 1000 m2 g?1, which was calculated on the basis of the commensurate–incommensurate transition with an enhancing factor ρ of 1.126. After hydrogenation at 653 K, no hydrogen desorption peaks were observed for FeNiCr powders derived from M (acac)n, and one peak at 828 K for a carbonaceous sample prepared from unmodified PAN fibers. From the most promising FeNiCr-carbon composite, another peak was recorded at 752 K in addition to the peak at 828 K. The former would be originated from hydrogen on novel sorption sites additionally created on the composite formation. 相似文献
67.
In this study, multi-objective genetic algorithms (GAs) are introduced to partial least squares (PLS) model building. This method aims to improve the performance and robustness of the PLS model by removing samples with systematic errors, including outliers, from the original data. Multi-objective GA optimizes the combination of these samples to be removed. Training and validation sets were used to reduce the undesirable effects of over-fitting on the training set by multi-objective GA. The reduction of the over-fitting leads to accurate and robust PLS models. To clearly visualize the factors of the systematic errors, an index defined with the original PLS model and a specific Pareto-optimal solution is also introduced. This method is applied to three kinds of near-infrared (NIR) spectra to build PLS models. The results demonstrate that multi-objective GA significantly improves the performance of the PLS models. They also show that the sample selection by multi-objective GA enhances the ability of the PLS models to detect samples with systematic errors. 相似文献
68.
New methodology to obtain a calibration model for noninvasive near-infrared blood glucose monitoring 总被引:1,自引:0,他引:1
Maruo K Oota T Tsurugi M Nakagawa T Arimoto H Tamura M Ozaki Y Yamada Y 《Applied spectroscopy》2006,60(4):441-449
This paper reports new methodology to obtain a calibration model for noninvasive blood glucose monitoring using diffuse reflectance near-infrared (NIR) spectroscopy. Conventional studies of noninvasive blood glucose monitoring with NIR spectroscopy use a calibration model developed by in vivo experimental data sets. In order to create a calibration model, we have used a numerical simulation of light propagation in skin tissue to obtain simulated NIR diffuse reflectance spectra. The numerical simulation method enables us to design parameters affecting the prediction of blood glucose levels and their variation ranges for a data set to create a calibration model using multivariate analysis without any in vivo experiments in advance. By designing the parameters and their variation ranges appropriately, we can prevent a calibration model from chance temporal correlations that are often observed in conventional studies using NIR spectroscopy. The calibration model (regression coefficient vector) obtained by the numerical simulation has a characteristic positive peak at the wavelength around 1600 nm. This characteristic feature of the regression coefficient vector is very similar to those obtained by our previous in vitro and in vivo experimental studies. This positive peak at around 1600 nm also corresponds to the characteristic absorption band of glucose. The present study has reinforced that the characteristic absorbance of glucose at around 1600 nm is useful to predict the blood glucose level by diffuse reflectance NIR spectroscopy. We have validated this new calibration methodology using in vivo experiments. As a result, we obtained a coefficient of determination, r2, of 0.87 and a standard error of prediction (SEP) of 12.3 mg/dL between the predicted blood glucose levels and the reference blood glucose levels for all the experiments we have conducted. These results of in vivo experiments indicate that if the parameters and their vibration ranges are appropriately taken into account in a numerical simulation, the new calibration methodology provides us with a very good calibration model that can predict blood glucose levels with small errors without conducting any experiments in advance to create a calibration model for each individual patient. This new calibration methodology using numerical simulation has promising potential for NIR spectroscopy, especially for noninvasive blood glucose monitoring. 相似文献
69.
Maruo K Oota T Tsurugi M Nakagawa T Arimoto H Hayakawa M Tamura M Ozaki Y Yamada Y 《Applied spectroscopy》2006,60(12):1423-1431
We have applied a new methodology for noninvasive continuous blood glucose monitoring, proposed in our previous paper, to patients in ICU (intensive care unit), where strict controls of blood glucose levels are required. The new methodology can build calibration models essentially from numerical simulation, while the conventional methodology requires pre-experiments such as sugar tolerance tests, which are impossible to perform on ICU patients in most cases. The in vivo experiments in this study consisted of two stages, the first stage conducted on healthy subjects as preliminary experiments, and the second stage on ICU patients. The prediction performance of the first stage was obtained as a correlation coefficient (r) of 0.71 and standard error of prediction (SEP) of 28.7 mg/dL. Of the 323 total data, 71.5% were in the A zone, 28.5% were in the B zone, and none were in the C, D, and E zones for the Clarke error-grid analysis. The prediction performance of the second stage was obtained as an r of 0.97 and SEP of 27.2 mg/dL. Of the 304 total data, 80.3% were in the A zone, 19.7% were in the B zone, and none were in the C, D, and E zones. These prediction results suggest that the new methodology has the potential to realize a noninvasive blood glucose monitoring system using near-infrared spectroscopy (NIRS) in ICUs. Although the total performance of the present monitoring system has not yet reached a satisfactory level as a stand-alone system, it can be developed as a complementary system to the conventional one used in ICUs for routine blood glucose management, which checks the blood glucose levels of patients every few hours. 相似文献
70.
AbstractSolvent extracts were compared with the parent gelatins by means of TLC and HPLC. The photographic effects of the various protein fractions are discussed. 相似文献