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101.
Kitaoka Haru Amano Ken-ichi Nishi Naoya Sakka Tetsuo 《Optimization and Engineering》2022,23(2):1033-1055
Optimization and Engineering - The Nelder-Mead (NM) method is a popular derivative-free optimization algorithm owing to its fast convergence and robustness. However, it is known that the method... 相似文献
102.
103.
We report on a direct measurement method and results of the point-to-point resolution for microns-thick amorphous specimens in the ultrahigh-voltage electron microscope (ultra-HVEM). We first obtain the ultra-HVEM images of nanometer gold particles with different sizes on the top surfaces of the thick epoxy-resin specimens. Based on the Rayleigh criterion, the point-to-point resolution is then determined as the minimum distance between centers of two resolvable tangent gold particles. Some values of resolution are accordingly acquired for the specimens with different thicknesses at the accelerating voltage of 2 MV, for example, 18.5 nm and 28.4 nm for the 5 μm and 8 μm thick epoxy-resin specimens, respectively. The presented method and results provide a reliable and useful approach to quantifying and comparing the achievable spatial resolution for the thick specimens imaged in the mode of transmission electron including the scanning transmission electron microscope. 相似文献
104.
On the treatments of heterogeneities and periodic boundary conditions for isogeometric homogenization analysis 下载免费PDF全文
Seishiro Matsubara Shin‐Nosuke Nishi Kenjiro Terada 《International journal for numerical methods in engineering》2017,109(11):1523-1548
The treatments of heterogeneities and periodic boundary conditions are explored to properly perform isogeometric analysis (IGA) based on NURBS basis functions in solving homogenization problems for heterogeneous media with omni‐directional periodicity and composite plates with in‐plane periodicity. Because the treatment of the combination of different materials in IGA models is not trivial especially for periodicity constraints, the first priority is to clearly specify points at issue in the numerical modeling, or equivalently mesh generation, for IG homogenization analysis (IGHA). The most awkward, but important issue is how to generate patches for NURBS representation of the geometry of a rectangular parallelepiped unit cell to realize appropriate deformations in consideration of the convex‐hull property of IGA. The issue arises from the introduction of overlapped control points located at angular points in the heterogeneous unit cell, which must satisfy multiple point constraint (MPC) conditions associated with periodic boundary conditions (PBCs). Although two measures may be conceivable, we suggest the use of multiple patches along with double MPC that imposes PBCs and the continuity conditions between different patches simultaneously. Several numerical examples of numerical material and plate tests are presented to demonstrate the validity of the proposed strategy of IG modeling for IGHA. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
105.
Wireless Personal Communications - Wireless sensor networks sense events, collect data and forward it to the infrastructural node, called sink, for further processing and assessment. The... 相似文献
106.
The spherulitic morphology in poly(butylene succinate-co-butylene carbonate)/poly(l-lactic acid) (PEC/PLLA) blends was investigated by atomic force microscopy (AFM) to obtain direct evidence for the formation of interpenetrated spherulites (IPS), where the spherulites of PEC penetrate into PLLA spherulites. The observation actually revealed that PEC crystals penetrated into interfibrillar regions of edge-on lamellae in a PLLA spherulite. The penetration process was also investigated by AFM with a temperature controller. An edge-on PLLA lamella or a fibril that ran nearly perpendicular to the growth direction of a PEC spherulite obstructed the growth of PEC spherulite. The PEC crystals filled the blocked space after growing around the PLLA lamella. These results showed that the spherulites of PEC and PLLA grow on the same layer instead of forming a layered structure of two spherulites. All the results supported the formation of IPS. 相似文献
107.
Kawakubo A Matsunaga T Ishizaki H Yamada S Hayashi Y 《Microscopy research and technique》2011,74(12):1161-1165
BACKGROUND: Zinc (Zn) has a potent stimulatory effect on osteoblastic bone formation and an inhibitory effect on osteoclastic bone resorption. PURPOSE: The effect of Zn on the function of matrix vesicles (MVs) remains controversial. The purpose of this study was to investigate the effect of Zn on alkaline phosphatase (ALP) activity of osteoblasts and in the initial biological MVs‐mediated mineral deposition. STUDY DESIGN: Osteoblasts were treated with varying concentrations of Zn dissolved in culture medium. After three, five, and seven days of culture, ALP activity was assayed. For the detection of a low level of calcium concentration in MVs, X‐ray fluorescence (XRF) analyses were applied. The effect of Zn for the transformation of calcium phosphate was analyzed using a scanning electron microscope fitted with an energy dispersive X‐ray microanalysis (EDX) system. RESULTS: The ALP activity of osteoblasts in culture medium supplemented with 1 × 10?5M of Zn was significantly increased at both five and seven days. XRF data demonstrated higher levels of calcium concentration over time in the Zn‐supplemented group. EDX data showed that mineral deposits beginning on day 3 were transformed from whitlockite to calcium phosphate near hydroxyapatite, and that Zn accelerated this transformation. CONCLUSIONS: The proper concentration of Zn increased the ALP activity of osteoblasts after five and seven days of incubation. The present XRF and EDX data suggest that the increase of mineral deposition with Zn exposure for one to five days might be mediated by the activation of ALP and calcium‐binding proteins. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc. 相似文献
108.
Biocomposite scaffolds composed of PVA, ovalbumin, cellulose nanocrystals, and nanohydroxyapatite were fabricated by freeze-drying method. The results revealed that the different fractions of nanohydroxyapatite and cellulose nanocrystals provide the mechanical strength and stiffness to the desired biocomposite scaffolds. In vitro biomineralization showed the formation of apatite onto the surface of obtained biocomposite scaffolds and increased as amount of nanohydroxyapatite increased. The obtained results suggest that the different combinations of these four biomaterials can be used to fabricate highly porous scaffolds with desired mechanical performance and degradation rate by adjusting ratio for potential use in low load-bearing applications. 相似文献
109.
Taga A Nishi T Honda Y Sato A Terashima H Suzuki K Kodama S Boki K 《Journal of oleo science》2007,56(8):429-434
Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half. 相似文献
110.
Mikihiro Yoshie Kazuya Kusama Risaka Tanaka Takanori Okubo Junya Kojima Yotaro Takaesu Keiichi Isaka Hirotaka Nishi Kazuhiro Tamura 《International journal of molecular sciences》2021,22(19)
Previous in vitro studies have suggested that calreticulin (CALR), which is responsible for the folding and quality control of glycoproteins, may be associated with decidualization. However, its precise role in regulating decidualization has not been explored in vivo. Here, we used pregnant rat models to examine endometrial CALR expression during the peri-implantation period. We also examined whether polypectomy, a procedure that could ameliorate infertility, alters the endometrial expression levels of CALR and several implantation factors in women diagnosed as infertile. In rats, uterine CALR was expressed at a high level at the implantation site, and a marked increase in CALR expression was observed in decidual cells of normal pregnancy. In addition, endometrial CALR expression was enhanced by either administration of estradiol-17β in the delayed implantation rat model or the artificial induction of decidualization in the pseudopregnant rat. In cultured stromal cells, siRNA-mediated silencing of CALR inhibited the decidual stimulus-induced expression of prolactin, decidual/trophoblast prolactin-related protein, and connexin 43. In humans, the endometrial expression levels of the mRNAs encoding CALR and the implantation-related factor insulin-like growth factor binding protein (IGFBP)-7 tended to increase after polypectomy. The strongest positive correlation between expression levels before polypectomy was observed for IGFBP-7 and CALR, and the strength of this correlation increased after the surgery. Thus, endometrial CALR may play a role in the formation of decidua, and the polypectomy of infertile patients may result in the co-operative expression of endometrial factors, including CALR, that could enhance endometrial receptivity. 相似文献