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21.
The process of cold seeding melt growth of GdBa2Cu3Oy (Gd123) bulk superconductors using NdBa2Cu3Oy (Nd123) thin films was reported. In addition, a novel cold seeding concept of combining MgO crystal and buffer pellet was also introduced. The misorientation caused by the lattice mismatch between MgO and Gd123 melt was overcome by choosing suitable heat treatment program and Gd2BaCuO5 (Gd211) content of the buffer pellet. The doping effect of soft ferromagnetic NiFe alloy particles was also reported. The bulk sample with 0.4% (mole fraction) doping amount shows the best performance on the flux trapping. The critical current density is largely enhanced under the external field of 1–2 T, which is promising for large-scale applications. This effect is originated from the substitution of Fe and Ni ions for the Cu sites contributing to magnetic flux pinning.  相似文献   
22.
Stroke is a major cause of death worldwide, leading to serious disability. Post-ischemic injury, especially in the cerebral ischemia-prone hippocampus, is a serious problem, as it contributes to vascular dementia. Many studies have shown that in the hippocampus, ischemia/reperfusion induces neuronal death through oxidative stress and neuronal zinc (Zn2+) dyshomeostasis. Glutathione (GSH) plays an important role in protecting neurons against oxidative stress as a major intracellular antioxidant. In addition, the thiol group of GSH can function as a principal Zn2+ chelator for the maintenance of Zn2+ homeostasis in neurons. These lines of evidence suggest that neuronal GSH levels could be a key factor in post-stroke neuronal survival. In neurons, excitatory amino acid carrier 1 (EAAC1) is involved in the influx of cysteine, and intracellular cysteine is the rate-limiting substrate for the synthesis of GSH. Recently, several studies have indicated that cysteine uptake through EAAC1 suppresses ischemia-induced neuronal death via the promotion of hippocampal GSH synthesis in ischemic animal models. In this article, we aimed to review and describe the role of GSH in hippocampal neuroprotection after ischemia/reperfusion, focusing on EAAC1.  相似文献   
23.
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC.  相似文献   
24.
In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g-1 for urea, 18 mg·g-1 for creatinine, and 20 mg·g-1 for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process.  相似文献   
25.
Twelve of 25 patients with mixed connective tissue disease complained of xerostomia and/or ocular symptoms of keratoconjunctivitis sicca. In addition to the clinical features of mixed connective tissue disease, all 12 patients had high titers of antibody to the ribonuclease-sensitive component of the extractable nuclear antigen. Eight patients had both clinical xerostomia and keratoconjunctivitis sicca, one had keratoconjunctivitis sicca and salivary gland enlargement, while there had xerostomia but no ocular complaints. Sj?rgren's syndrome was confirmed in all 12 patients by means of Schirmer's tests, Rose Bengal staining tests, salivary gland scintiscans, radionuclide excretion studies in saliva, parotid sialographies, and lip biopsies. At least three of these tests were abnormal in all patients.  相似文献   
26.
Car navigation systems play a prominent role in road traffic safety and traffic regulation. However, it is necessary to improve the route guidance of car navigation systems so that they accurately and quickly recognize small differences in location. Thus, to increase the ease of understanding and safety of car navigation systems, navigation systems based on augmented reality have been proposed for providing guidance at road intersections. We are currently developing a car navigation system based on augmented reality, called AR‐Navi. We investigated designs for the display of road intersection guidance that can be easily understood even when limited information is available and proposed a “best shot” display method that does not use moving images. In addition, we implemented a prototype system that includes these methods and conducted driving experiments on public roads to evaluate the ease of understanding and safety of AR‐Navi. Using the evaluation results, we confirmed that the ease of understanding and safety is similar in the case of AR‐Navi and CG‐Navi. We also clarified the characteristics of AR‐Navi. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 43–54, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22278  相似文献   
27.
We newly generated an RNA-sequencing-based microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC). Analysis of the signature revealed that both strands of some miRNAs, including miR-139-5p (the guide strand) and miR-139-3p (the passenger strand) of miR-139, were downregulated in HNSCC tissues. Analysis of The Cancer Genome Atlas confirmed the low expression levels of miR-139 in HNSCC. Ectopic expression of these miRNAs attenuated the characteristics of cancer cell aggressiveness (e.g., cell proliferation, migration, and invasion). Our in silico analyses revealed a total of 28 putative targets regulated by pre-miR-139 (miR-139-5p and miR-139-3p) in HNSCC cells. Of these, the GNA12 (guanine nucleotide-binding protein subunit alpha-12) and OLR1 (oxidized low-density lipoprotein receptor 1) expression levels were identified as independent factors that predicted patient survival according to multivariate Cox regression analyses (p = 0.0018 and p = 0.0104, respectively). Direct regulation of GNA12 and OLR1 by miR-139-3p in HNSCC cells was confirmed through luciferase reporter assays. Moreover, overexpression of GNA12 and OLR1 was detected in clinical specimens of HNSCC through immunostaining. The involvement of miR-139-3p (the passenger strand) in the oncogenesis of HNSCC is a new concept in cancer biology. Our miRNA-based strategy will increase knowledge on the molecular pathogenesis of HNSCC.  相似文献   
28.
For a robot to cohabit with people, it should be able to learn people’s nonverbal social behavior from experience. In this paper, we propose a novel machine learning method for recognizing gestures used in interaction and communication. Our method enables robots to learn gestures incrementally during human–robot interaction in an unsupervised manner. It allows the user to leave the number and types of gestures undefined prior to the learning. The proposed method (HB-SOINN) is based on a self-organizing incremental neural network and the hidden Markov model. We have added an interactive learning mechanism to HB-SOINN to prevent a single cluster from running into a failure as a result of polysemy of being assigned more than one meaning. For example, a sentence: “Keep on going left slowly” has three meanings such as, “Keep on (1)”, “going left (2)”, “slowly (3)”. We experimentally tested the clustering performance of the proposed method against data obtained from measuring gestures using a motion capture device. The results show that the classification performance of HB-SOINN exceeds that of conventional clustering approaches. In addition, we have found that the interactive learning function improves the learning performance of HB-SOINN.  相似文献   
29.
Optimizing inter-processor (PE) communication is crucial for parallelizing compilers for message-passing parallel machines to achieve high performance. In this paper, we propose a technique to eliminate redundant inter-PE messages. This technique utilizes data-flow analysis to find a definition point that corresponds to a use point where the definition and the use occur in different PEs. If several read accesses occurred in the same PE use the data defined at the same definition point in another PE, redundant inter-PE messages are eliminated as follows: only one inter-PE communication is performed for the earliest read access and the previously received data are used for the following read. In order to guarantee the consistency of the data, a valid flag and a sent flag are provided for each chunk of received data. The control of these flags is equivalent to the coherence control by the self invalidation on a compiler aided cache coherence scheme.  相似文献   
30.
In this paper, the optimization of a generic function of a lipstick manufacturing process is discussed. Traditionally, the quality of lipsticks has been measured by objective quality characteristics such as appearance. Sensory tests, which are not recommended in quality engineering, had been used to evaluate such quality characteristics. That is because these quality characteristics are not stable due to the changes of environmental conditions such as between-lot variability and seasonal variation. When such quality problems occurred, manufacturing conditions were adjusted from time to time, which is known as fire fighting or 'mole beating' in Japanese. Among those objective quality characteristics, the ones such as scratches, colour uniformity or breaking during usage are manufacturing related. As a generic function, the stress/strain relationship was investigated and the results showed that the relationship has satisfied Hook's Law with a good improvement.  相似文献   
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