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991.
Y Matsui T Inoue T Matsushita T Yamada M Yamamoto Y Sumigama 《Water science and technology》2005,51(3-4):329-337
In the prediction of time-series concentrations of herbicides in river water with diffuse-pollution hydrological models, farming schedules (the dates of herbicide application and drainage of irrigation water from rice paddies) greatly affect the runoff behavior of the herbicides. For large catchments, obtaining precise data on farming schedules is impractical, and so the model input inevitably includes substantial uncertainty. This paper evaluates the effectiveness of using the Monte-Carlo method to generate sets of estimated farming schedules to use as input to a GIS-based basin-scale runoff model to predict the concentrations of paddy-farming herbicides in river water. The effects of using the Monte-Carlo method to compensate for uncertainty in the evaluated parameters for herbicide decomposition and sorption were also evaluated. 相似文献
992.
Hisashi Kohkame Hideki Asano Masao Goto Yasushi Miyano 《Polymer Engineering and Science》1993,33(10):607-613
Acrylonitrile-acrylic elastomer-styrene terpolymer (AAS resin) was developed to improve weatherability of acrylonitrile-butadiene-styrene terpolymer (ABS resin). To compare thermal stability of both resins, test parts of AAS and ABS resins were injection molded at various temperatures and the Izod impact value of the resulting moldings was measured. A study was then made to find the relationship between this value and deterioration of the resins. AAS resin was molded at temperatures from 180°C to 280°C. The impact value of the resulting moldings was almost constant for temperatures up to 260°C, with the first major decrease occurring at 280°C. In contrast, the impact value of conventional ABS resin moldings constantly decreased as the molding temperature was elevated. To explain this phenomenon in both resins, two types of test program steps were undertaken: (1) The cause of the change in characteristics of the AAS resin was determined by obtaining its stress-strain curve in a high-speed flexural strength test; measuring its infrared absorption spectrum; and determining its flow properties with a constant-pressure extrusion type rheometer; (2) the distribution of elastomer in the resin was observed with an electron microscope. It was found that the decrease of impact values of both resins at high temperatures is caused by deterionration of the elastomer. Also, it was found that the different relationships between the impact value and molding temperatures for AAS and ABS resins are due to the difference between the rates of thermal degradation of the acrylic elastomer and butadiene elastomer. 相似文献
993.
We succeeded in obtaining strained Si1−yCy films at a substrate temperature of 200 °C by the hot-wire cell method. The substitutional carbon concentration in films annealed at 700 °C was 0.9%, while it was limited to 0.13% for a sample grown by gas-source molecular beam epitaxy (MBE) at a substrate temperature of 700 °C. We investigated the thermal stability of strained Si1−yCy films for device application. Annealing at over 900 °C caused the formation of 3C-SiC and relaxation of the strain occurred. From this result, we found that the process temperature should be lower than 800 °C. A low-temperature MOSFET process, in which all process temperatures after deposition of Si1−yCy were lower than 800 °C, was developed and a strained Si1−yCy MOSFET was fabricated. 相似文献
994.
In the progeny of the monosomic addition line of common wheat, Triticum aestivum, carrying the gametocidal chromosome of Aegilops cylindrica, deletion chromosomes carrying the break point within the nucleolar organizing region of chromosome 1B appeared. Attempts were made to amplify the break points by PCR using primers of telomere and rDNA (rRNA gene). In one deletion line, specific amplification of DNA fragments including the 18S rRNA gene, telomere repeats, and their junction occurred. At the junction of telomere and rRNA gene there was a 31-bp inverted duplication of the rRNA gene. Telomere sequences were initiated from the sequence TAG in the duplication. Between the duplications a small sequence was also inserted. This novel DNA sequence at the break point indicates that the breakage-fusion-bridge cycle(s) took place after the first chromatin breakage by the gametocidal gene. 相似文献
995.
H Iwase Y Yamada S Ootani Y Sasaki M Nagao K Iwadate T Takatori 《Canadian Metallurgical Quarterly》1998,94(1-2):9-14
This paper describes risk factors for dental caries identified among 491 2-year-olds in the city of Ume?, Sweden. The study was performed as a risk screening for dental caries according to a method developed for use by dental assistants. The sugar consumption was high, 80% of the 2-year-olds had sweets once a week or more and 25% had sweet beverages once a day or more frequently. In addition, 14% of the children had a meal at night and most common were formula, bovine milk or breastmilk. The majority of the parents brushed the child's teeth at least daily using fluoride toothpaste. Among the children 6% had a chronic somatic disorder and 6% had an intolerance towards specific foods, milk being the most common. The high level of sugar consumption indicates that improved dental health education focusing on the importance of limiting sugar consumption is needed among parents with young children. 相似文献
996.
The prevalence of plasma platelet-activating factor (PAF) acetylhydrolase deficiency was investigated in 477 healthy Japanese individuals and 985 patients with various cardiovascular diseases. The genotype for this enzyme with regard to a G994-->T mutation (MM, normal; Mm, heterozygote; mm, mutant homozygote) was determined by an allele-specific polymerase chain reaction in 80 subjects shown to have no or low plasma activity (<10 nmol/min/ml). In 72 subjects, the genotype was consistent with plasma enzyme activity; 44 individuals with no activity were mm, and 28 with low activity were Mm. However, eight subjects with the MM genotype showed plasma enzyme activities of <10 nmol/min/ml. Determination of the DNA sequence of exon 9 of the plasma PAF acetylhydrolase gene in these eight subjects revealed a previously unidentified A1001-->G missense mutation, resulting in a Gln281-->Arg substitution, in a 72-year-old woman with coronary artery disease, essential hypertension, and no plasma enzyme activity. Site-directed mutagenesis in vitro showed that the corresponding recombinant mutant protein lacked PAF acetylhydrolase activity. Thus, the Gln281-->Arg substitution appears responsible for the loss of plasma PAF acetylhydrolase activity. 相似文献
997.
Various methods are now available to identify the molecular partners of the component of a signal transduction pathway. Some interactions, however, can be technically difficult to detect because they depend upon transient tyrosine phosphorylation. Here, we present a simple affinity chromatography approach based on synthetic phosphopeptides to purify potential partners of phosphotyrosine-containing proteins. With this approach, we confirm the previously characterized interaction between Grb2 and the EGF receptor, and we identify novel partners of the IGF-1 receptor and of the JAK proteins. Methenyltetrahydrofolate synthetase (MTHFS) was identified as a potential mediator of IGF-1R dependent transformation. P85alpha, the regulatory subunit of PI3 kinase, was identified as one of four proteins recruited by a phosphopeptide mimicking a motif conserved in all JAK family members. 相似文献
998.
Y Ohashi Y Nakai A Tanaka Y Kakinoki Y Washio A Kato T Masamoto K Yamada M Hayashi 《Canadian Metallurgical Quarterly》1998,124(12):1337-1346
BACKGROUND: Recent double-blind placebo-controlled trials have clearly shown the efficacy of immunotherapy for perennial allergic rhinitis. However, the exact working mechanisms related to the clinical effect of immunotherapy remain unclear. OBJECTIVES: To monitor the changes over time in immunologic parameters in children who received immunotherapy for perennial allergic rhinitis, and to elucidate the working mechanisms of immunotherapy related to its clinical efficacy. DESIGN: Nineteen children with perennial allergic rhinitis due to Dermatophagoides farinae enrolled in this prospective open study. Venous blood was collected to determine levels of specific IgE, specific IgG4, soluble interleukin 2 receptor, interleukin 4, soluble intercellular adhesion molecule 1, and soluble vascular cell adhesion molecule 1 at enrollment and 1, 2, 3, 5, and 10 years after enrollment. RESULTS: Immunotherapy affected serum levels of specific IgE, specific IgG4, soluble interleukin 2 receptor, interleukin 4, and soluble intercellular adhesion molecule 1, but not soluble vascular cell adhesion molecule 1. The rates of increase of levels of specific IgG4 and the rates of decrease of levels of soluble interleukin 2 receptor were correlated with the rates of decrease of symptom scores during the first 3 years of treatment, but not after 5 years. The rates of decrease in levels of soluble intercellular adhesion molecule 1 were correlated with the rates of decrease in symptom scores at 3 and 5 years after the beginning of the course of immunotherapy. The rates of decrease in levels of specific IgE and interleukin 4 were correlated with the rates of decrease in symptom scores after 5 and 10 years of treatment, but not during the first 3 years. CONCLUSION: Each modulation in levels of specific IgE, specific IgG4, soluble interleukin 2 receptor, interleukin 4, and soluble intercellular adhesion molecule 1 contributed to the clinical effect of immunotherapy in particular phases of treatment for children with perennial allergic rhinitis. 相似文献
999.
The substantia nigra is innervated by massive inhibitory GABAergic projections from the striatum and globus pallidus, deafferentation of which is supposed to lead to anterograde trans-synaptic degeneration of the nigral neurons. An immunohistochemical method was used to examine the induction of 72,000 mol. wt heat shock protein in the substantia nigra following cerebral hemitransection or transient middle cerebral artery occlusion. At three and four days post-transection, strong immunoreactivity for 72,000 mol. wt heat shock protein was found in the ipsilateral substantia nigra pars reticulata. Light microscopic observation revealed a number of pars reticulata neurons showing strong immunoreactivity for 72,000 mol. wt heat shock protein in their perikarya and proximal processes. In addition, Golgi-like stained neurons with dystrophic features were occasionally observed in the ipsilateral substantia nigra pars reticulata. The immunoreactivity for 72,000 mol. wt heat shock protein in the ipsilateral pars reticulata gradually declined and almost disappeared by 15 days after transection. No apparent induction of 72,000 mol. wt heat shock protein was found in the substantia nigra pars compacta throughout the time period examined. Massive striatal ischemic injury produced by transient middle cerebral artery occlusion also induced expression of 72,000 mol. wt heat shock protein in the pars reticulata neurons three and four days postoperatively. These findings suggest that deafferentation of the striatal or striatopallidal inputs per se is a harmful stress for the substantia nigra pars reticulata neurons, inducing 72,000 mol. wt heat shock protein synthesis. The present data may contribute to our understanding of the molecular basis of the pathomechanism of the transneuronal regression of substantia nigra pars reticulata neurons, which may occur after removal of inhibitory GABAergic inputs. 相似文献
1000.
Tadaomi Miyazaki Yasushi Nishida Satomi Kokubu Shuichiro Kawamata 《Electrical Engineering in Japan》1992,112(3):32-38
A lightning strength parameter α (denoted as LSP or LAIDO), which is used for characterizing the phenomena of lightning activity, has been proposed, where α is defined by the characteristic energy obtained from the energy distribution of a radiated field component E in the electrostatic field changes produced by lightning discharge. Here, it is observed that the energy distribution of Eγ components is Maxwellian type. To prove more clearly the forementioned assumption from another viewpoint, changes of the amplitudes of the electrostatic field component ES were measured and their distribution functions constructed. In the cloud-to-ground lightning discharges, the ES components have a positive sign in the changes. However, those changes in the intercloud discharges are observed with either a negative or positive change depending on the distance between the striking point and the observation site. Therefore it is necessary to sum the numbers of occurrences of both positive and negative components for constructing an energy distribution of the ES component. A fieldmill and a pair of doughnut-shaped electrostatic antennas are used in measuring the changes of the ES component. As a result it is found that the changes of the amplitudes of the ES components have a Maxwelliantype energy distribution. A characteristic energy β is defined which is obtained from the component of the electrostatic fields as a measure of LSP. Based on comparison of α and β it is clarified that β has the same characteristic nature with α. The lightning activity could be estimated from β. 相似文献