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61.
Takahiro Funami Sakie Noda Makoto Nakauma Sayaka Ishihara Rheo Takahashi Saphwan Al-Assaf Shinya Ikeda Katsuyoshi Nishinari Glyn O. Phillips 《Food Hydrocolloids》2009,23(2):548-554
Aqueous solutions of gellan gum with comparable molecular mass but with different acyl contents were investigated by atomic force microscopy and rheological measurements in the presence of sodium chloride (NaCl). Results obtained were discussed in relation to our previous report using potassium chloride (KCl) as an added salt. For a low-acyl sample, continuous fibrous network structures were identified microscopically as in the case of KCl. The network structures were more heterogeneous than those formed with KCl in terms of the height distribution of molecular assemblies. Rheological thermal hysteresis between sol–gel transitions was detected as in the case of KCl. The storage modulus (G′) of the gelled system was ca. 15% of the corresponding data with KCl at 20 °C. For a high-acyl sample, no continuous network structures were identified but branches with observable ends were identified as in the case of KCl. The hysteresis was less evident than the corresponding data with KCl and for the low-acyl sample with NaCl. Also, G′ values at 20 °C were ca. 30% and 20% of the corresponding data with KCl and for the low-acyl sample with NaCl, respectively. Continuousness and homogeneity of network structures related to the hysteresis and elasticity of the system, respectively. 相似文献
62.
Kaoru Abe Yasuhiro Sakurai Akira Okuyama Kazuhiro Sasaki Kei Tawarada 《Journal of the science of food and agriculture》2009,89(6):1097-1100
BACKGROUND: The behavior of cadmium in ecosystems needs to be monitored because of the human toxicity of this heavy metal. The need recently arose for a simple and quick on‐site test for trace levels of Cd in food and environmental samples. In response, an immunochromatographic assay kit for detecting Cd was manufactured by Kansai Electric Power Co. of Japan. This kit uses the antigen–antibody complex reaction between the Cd–EDTA complex and an anti‐Cd–EDTA antibody and shows the results in terms of the degree of color developed on a test paper. We previously reported the successful use of this kit to determine Cd concentrations in brown rice. Here, we applied the kit to the determination of Cd concentrations in rice foliage and soil. RESULTS: Cadmium in rice foliage was not extracted successfully by the method used for brown rice. However, it was successfully extracted by 0.1 mol L?1 HCl solution at a rice foliage:HCl ratio of 1:20, and coexisting metals were removed sufficiently by the column treatment. The Cd concentrations determined by immunochromatographic assay were well correlated with the values obtained by acid decomposition and inductively coupled plasma mass spectrometry. The 0.1 mol L?1 HCl‐extractable Cd concentration in soil was also determined successfully with the kit. CONCLUSION: Approximate Cd concentrations in rice plants and 0.1 mol L?1 HCl‐extractable Cd concentrations in soil can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2009 Society of Chemical Industry 相似文献
63.
In recent textured image segmentation, Bayesian approaches capitalizing on computational efficiency of multiresolution representations have received much attention. Most of the previous researches have been based on multiresolution stochastic models which use the Gaussian pyramid image decomposition. In this paper, motivated by nonredundant directional selectivity and highly discriminative nature of the wavelet representation, we present an unsupervised textured image segmentation algorithm based on a multiscale stochastic modeling over the wavelet decomposition of image. The model, using doubly stochastic Markov random fields, captures intrascale statistical dependencies over the wavelet decomposed image and intrascale and interscale dependencies over the corresponding multiresolution region image. 相似文献
64.
To evaluate the mechanical strength of fiber reinforced composites it is necessary to consider singular stresses at the end of fibers because they cause crack initiation, propagation, and final failure. The singular stress is expressed by generalized stress intensity factors defined at the corner of fibers. As a 2D model an interaction between rectangular inclusions under longitudinal tension is treated in this paper. The body force method is used to formulate the problem as a system of singular integral equations with Cauchy-type or logarithmic-type singularities, where the unknown functions are the densities of body forces distributed in infinite plates having the same elastic constants as those of the matrix and inclusions. In order to analyze the problem accurately, the unknown functions are expressed as piecewize smooth functions using two types of fundamental densities and power series, where the fundamental densities are chosen to represent the symmetric stress singularity of 1/r
1–
1 and the skew-symmetric stress singularity of 1/r
1–
2. Then, generalized stress intensity factors at the end of inclusions are systematically calculated for various locations, spacings and elastic modulus of two rectangular inclusions in a plate subjected to longitudinal tension. 相似文献
65.
Okamura T Takeno T Dohi M Yasumasa I Hayashi T Toyoda M Noda H Fukuda S Horie N Ohsugi M 《Journal of Bioscience and Bioengineering》2000,89(5):474-478
With thrombosis a major cause of death in Japan and the Western world, thrombin-inhibitory agents that constrain the formation of fibrin are sought. We screened for basidiomycetes showing anti-thrombin activity and isolated Laetiporus sulphureus. However, it was difficult to cultivate and its form was not satisfactory. We therefore used protoplast fusion between L. sulphureus and the commonly cultivated basidiomycete Hypsizygus marmoreaus to obtain cultivable basidiomycetes that produced an anti-thrombin substance. For the protoplast fusion of L. sulphureus and H. marmoreaus, the protoplast concentration, alternating electric field intensity, dielectrophoresis duration, and field pulse intensity used were of 1 x 10(7) protoplasts/ml, 100 V/cm.1 MHz, 60 s, and 8 kV/cm, respectively. The number of regenerated colonies obtained was 4961, from which 43 strains were selected for electrophoretic analysis. Four of the fusants were found to have a band from each parent in isozyme patterns obtained using their crude extract. The fruiting bodies of the fusants were very similar to those of H. marmoreaus. Crude extract from each of the fusants and from L. sulphureus showed anti-coagulative activity in terms of the thrombin clotting time. We thus obtained improved basidiomycetes that produce an anti-thrombin substance, are easily cultivated, and whose form resembles H. marmoreaus, a commonly used culinary mushroom. 相似文献
66.
T. Furukawa K. Noda T. Fujimoto T.H. Uesugi S. Shibuya M. Torikoshi 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2006,560(2):191-196
In order to define the optical parameters of a slowly extracted beam at the entrance of the extraction channel and to realize optical matching with the beam line, the outgoing separatrix was measured at HIMAC. Modifying the lattice parameters of the ring model according to the measurement result, the simulation result makes it possible to predict the optical parameters at the extraction channel. As a result, it was experimentally verified that optical matching of the slowly extracted beam with the transport line was realized. The measured beam size and dispersion functions were in good agreement with the calculation result at each monitor in the transport line. Particle tracking also predicts the beam profile at each profile monitor in the beam line. Further, a quasi-parallel beam was demonstrated by changing the beam optics in the beam line. 相似文献
67.
H Bai R Morishita I Kida T Yamakawa W Zhang M Aoki H Matsushita A Noda R Nagai Y Kaneda J Higaki T Ogihara Y Sawa H Matsuda 《Canadian Metallurgical Quarterly》1998,5(6):761-769
OBJECTIVE: To define the distribution and determinants of cardiovascular disease events among participants undergoing long-term antihypertensive therapy, and to stratify them into risk groups on the basis of pretreatment clinical profiles. DESIGN: A prospective cohort study of participants in a worksite-based antihypertensive treatment program in New York city (1973-1994). PATIENTS: We studied 8690 systematically treated patients who had at least 6 months of follow-up (average of 5.7 years) and, at entry, had had a systolic blood pressure of > or = 160 mmHg or a diastolic blood pressure of > or = 95 mmHg (after 1992 > or = 140/90 mmHg), or had been being administered antihypertensive medication. MAIN OUTCOME MEASURES: Blood pressure and incidence of morbid and mortal cardiovascular events. RESULTS: Blood pressure control (to 140 +/- 3/87 +/- 7 mmHg) was achieved by the first year and maintained through 18 years of therapy. In nearly 50,000 person-years of follow-up, there were 468 cardiovascular disease events [myocardial infarction including revascularization (282), strokes (93), congestive heart failure (30) and other cardiovascular deaths (63)]. Deaths from cardiovascular disease events accounted for 68% of all deaths. Myocardial infarction was most common throughout, but congestive heart failure incidence surpassed stroke incidence after 10 years. A scheme for risk stratification was constructed after analysis of the independent association of baseline factors and incident cardiovascular events. Upon the basis of ease of ascertainment and their demonstrated associations with occurrence of cardiovascular disease during treatment, we selected five pretreatment factors (history of heart attack, stroke, diabetes, age > or = 55 years and pulse pressure > or = 60 mmHg) to stratify patients into four groups. Those with no risk factor had a low risk (n=2999), those with one had a moderate risk (3042), those with two had a high risk (2237), and those with three or more had a very high risk (412). Overall, the unadjusted rates of incidence of cardiovascular disease events per 1000 person-years for patients in very high and low risk groups differed by factors of six and 14 for men and women, respectively. CONCLUSION: These results demonstrate that long-term control of blood pressure can be achieved in a general population. Nevertheless, cardiovascular disease events still accounted for most morbidity and mortality among these 'recovered' hypertensive patients. At entry, on the basis of readily identifiable characteristics, it was possible to stratify patients according to likelihood of subsequent events occurring despite control of blood pressure. This scheme could provide the basis for targeting more aggressive therapy where the potential for further cardioprotection is greatest. 相似文献
68.
T Taguchi S Tsukagoshi H Furue H Niitani K Noda 《Canadian Metallurgical Quarterly》1998,25(12):1899-1907
Oxaliplatin is a new platinum derivative. A multicentric phase I study was conducted with a monotherapy of Oxaliplatin. A total of 20 patients were enrolled who had histologically proven 6 ovarian cancers, 5 uterine cervix cancers, 3 lung cancers, 3 breast cancers, 1 endometrial cancer, 1 gastric cancer, and 1 colorectal cancer. Oxaliplatin was administered as a 2-hour infusion at doses of 20, 40, 80, 130, and 180 mg/m2 every 3 weeks, for a total of 30 cycles. A dose-related and reversible peripheral sensory neuropathy was the dose-limiting toxicity with minimal hematotoxicity and no nephrotoxicity. No hydration was needed. The plasma platinum concentration was biphasically decreased. Cmax and AUC were dose-dependent. T1/2 beta was 31.3 hours. The recommended dose for further studies was 130 mg/m2. A partial response was observed in endometrial cancer. 相似文献
69.
70.
This study describes a scenario-driven conceptual design information model and its formation from the viewpoint of the designers cognition, which is a fundamental part of practical design support tools. Four design meetings were observed in a company, at intervals of several weeks, in order to derive the model. The model consists of information elements generated through the cognitive design problem-solving process, which is a basic design process defined in this study. The study describes the relationship among these information elements, which illustrate the design information model and its formation. The model described in this study is based on scenarios, which promote the evolution of product design. Examples of designers discourse in the design meetings are presented to validate the model. 相似文献