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51.
Shozo Miyazaki Akie Takahashi Kunihiko Itoh Mariko Ishitani Masatake Dairaku Mitsuo Togashi 《Drug development and industrial pharmacy》2013,39(7):780-787
Background: Oral sustained release gel formulations may provide a means of administering drugs to dysphagic and geriatric patients who have difficulties with handling and taking oral dosage forms. Aim: We have designed gel formulations for the oral administration of paracetamol with suitable rheological characteristics for ease of administration to patients with swallowing difficulties and sufficient integrity in the acidic environment of the stomach to achieve a sustained release of this drug. Method: Gels formed by gelatin, agar, gellan, pectin, and xyloglucan were assessed for suitable gel strength and in vitro and in vivo release characteristics. Results: Gellan (1.5%?w/v) and xyloglucan gels (1.5%?w/w) had acceptable gel strengths for ease of swallowing and retained their integrity in the rat stomach sufficiently well to sustain the release of paracetamol over a period of 6 hours. Comparison of 1.5%?xyloglucan gels with a commercially available preparation with identical paracetamol concentrations demonstrated improved sustained release properties of the xyloglucan gels. Conclusions: Gels formed by gellan and xyloglucan have suitable rheological and sustained release characteristics for potential use as vehicles for oral delivery of drugs to dysphagic patients. 相似文献
52.
CdSe microcrystals were successfully dispersed in GeO2 glass andCaF2 crystal thin films by rf-sputtering. All films preparedshowed the blue shift of absorption edge in visible spectra due toquantum size effect. The amount of the blue shift of the filmsincreased with decreasing the size of the microcrystals. Comparingthe amount of the particle size–depending blue shift of CdSemicrocrystals dispersed in between the GeO2, CaF2 and SiO2 matricies, the influence of the matrix on the shift was found.Therefore, it can be said that there is an influence of the matrix onthe quantum size effect. From the modified theoretical calculation,the influence of matrix was considered to appear through Coulombinteraction between electrons and holes. 相似文献
53.
54.
This article presents a study of the effect of through-the-thickness stitching yarns upon the strength and failure behavior
of multidirectionally reinforced composites. The in-plane yarns were placed in four directions (0,±45, 90) to form a quasi-isotropic
preform, which had open spaces between adjacent yarns. These interyarn spaces allowed easy insertion of the through-the-thickness
stitching yarns without significant damage of the in-plane fibers. Fiber volume fractions of over 54 pct were obtained by
this method. The through-the-thickness yarn sizes used in this study were 2, 4, and 6 kilo-filament (kf). Non-stitched performs
were also manufactured with the same fiber content and by the same procedure as the stiched preforms for the control experiments.
All preforms were infiltrated with epoxy resin by the resin transfer molding (RTM) technique. In-plane tensile and compressive
strength, interlaminar shear strength, and mode I fracture toughness of the carbon/epoxy composites were measured at three
through-the-thickness yarn contents. Although the through-the-thickness yarns significantly enhanced the mode I fracture toughness,
they tended to degrade the in-plane tensile and compressive strength. The failure process under interlaminar shear loading
by double notch shear tests showed two distinct stages: the fiber-matrix interfacial failure followed by the breakage/debonding
of the through-the-thickness yarns. The through-the-thickness yarns caused a reduction of the initial failure load in the
first stage but could enhance the final failure load in the second stage. In composites with 6 kf through-the-thickness yarns,
the final failure load could exceed the initial failure load. Scanning electron microscope (SEM) and optical microscopic examinations
were also conducted for observing the failure mechanisms and fracture surfaces.
This article is based on a presentation made in the Symposium “Mechanisms and Mechanics of Composites Fracture” held October
11–15, 1998, at the TMS Fall Meeting in Rosemont, Illinois, under the auspices of the TMS-SMD/ASM-MSCTS Composite-Materials
Committee. 相似文献
55.
K. Ohkawa S. Shimizu H. Sato T. Komaru W. Futako T. Kamiya C. M. Fortmann I. Shimizu 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Stability against light soaking was studied for amorphous silicon (a-Si:H) solar cells using three different i-layers; (a) device-quality a-Si:H (standard a-Si:H) with bandgap of 1.75 eV, (b) narrow bandgap (1.55 eV) a-Si:H fabricated by Ar* chemical annealing and (c) a-Si:H(Cl) fabricated from SiH2Cl2. Both the narrow bandgap a-Si:H and the a-Si:H(Cl) solar cells showed much improved stability than that of the standard a-Si:H solar cells: e.g., fill factor of the narrow bandgap a-Si:H cell only slightly decreased from 56% to 53%, while that of the standard a-Si:H cell degraded from 62% to 51%. In addition, mobility–lifetime products of the a-Si:H(Cl) cell also exhibited improved stability than that of the standard a-Si:H solar cell. 相似文献
56.
57.
58.
Noninvasive Measurement of the Volume Elastic Modulus in Finger Arteries Using Photoelectric Plethysmography 总被引:2,自引:0,他引:2
Shimazu Hideaki Yamakoshi Ken-Ichi Kamiya Akira 《IEEE transactions on bio-medical engineering》1986,(8):795-798
A method for the nonivasive measurement of the volume elastic modulus (Ev) in human finger arteries was developed. The volume change ratio and pulse pressure in the arteries were simultaneously determined by a transmittance type infrared photoelectric plethysmograph and a volume oscillometric sphygmomanometer using an occlusive cuff. The Ev values could be obtained at a desired transmural pressure level of the arteries which was controlled by the cuff. A clear difference was revealed between the Ev values obtained in the fingers of two male subjects of 33 and 65 years old. The values determined by this method were compared to those calculated from pulse wave propagation velocity (Evp) obtained simultaneously in the fingers of 11 subjects. The linear regression equation was Ev = 1.31 Evp ?0.117 with a correlation coefficient r = 0.893 (n = 39). These results suggest that this should be a useful and noninvasive method of evaluating changes in arterial elasticity accompanying aging and perhaps influenced by accompanying hypertension or arteriosclerosis. 相似文献
59.
The possibility of thermal proof testing with thermal stress induced by quenching was examined. For this purpose, the bending strength and the critical temperature difference for quenching into water and quench oil for soda-lime-silica glass were measured before and after proof testing by quenching the specimens into water, ethyl alcohol, silicon oil and quench oil. Proof testing by water, ethyl alcohol and silicon oil quenching modified the distribution of the critical temperature difference as expected, but not that of the bending strength at all. It is suggested that proof testing by rapid quenching is a useful method for truncating the critical temperature difference distribution of ceramic components of heat engines and so on. 相似文献
60.
Izumi Kita Tomohiro Shibata Yuki Kamiya Daishi Kato Kazuo Kunieda Keiji Yamada Kazushi Ikeda 《Artificial Life and Robotics》2009,14(3):375-378
To increase the productivity of knowledge workers, it is necessary to manage their organization so that they are motivated
to collaborate with each other for their synergy. However, it is difficult for managers to grasp the explicit interactions
of workers in the organization all the time. Owing to advanced communications technology, and the reduced size and improved
capabilities of computers, we are able to record group behaviors as logging data in the office. The aim of this study is to
extract features of group behavior from long-range office-logging data. We apply principal component analysis to the data
matrix whose element is the mean travel velocity calculated from an individual’s trajectory per day. The results demonstrate
the feasibility of our approach, since nontrivial informative group features can be extracted. 相似文献