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121.
CMOS Smart Sensor for Monitoring the Quality of Perishables 总被引:1,自引:0,他引:1
We developed a CMOS integrated-circuit sensor to monitor the change in quality of perishables that depends on surrounding temperatures. Our sensor makes use of the fact that the temperature dependence of the subthreshold current in MOSFETs is analogous to that of the degradation of perishables. The sensor is attached to perishable goods such as farm and marine products and is distributed from producers to consumers along with the goods. During their distribution process, the sensor measures the surrounding temperatures and emulates the degradation of the goods caused by the temperature. By reading the output of the sensor, consumers can determine whether the goods are fresh or not. Our sensor consists of subthreshold CMOS circuits with a low-power consumption of 10 muW or lower 相似文献
122.
We developed a "pH-jump method" to obtain transparent solutions of E5531, a synthetic lipid A analog, at neutral pH for pharmaceutical injection. E5531 has two pKa: pKa1 = 6.0 and pKa2 = 9.3. At pH 11.0, E5531 was dispersed as a dissociated form, and the phase transition temperature Tc of E5531 was determined to be 30 degrees C using differential scanning calorimetry (DSC). Based on these results, the pH-jump method procedure involves dispersing E5531 at pH 11.0 (above pKa2) at 50 degrees C (above Tc) and mixing with a phosphate buffer to neutralize the pH. No degradated products of E5531 were observed at 50 degrees C for 3 hr during dispersing in the alkaline solution. The turbidity of samples prepared with the pH-jump method was similar to that of water and superior to the samples dispersed directly in neutral pH. This method does not need mechanical power and is suitable for large-scale production. 相似文献
123.
K. Kaigawa T. Shibata Y. Nakamura K. Asai M. Tanaka H. Sakai T. Tsurumi 《Journal of Materials Science》2002,37(6):1155-1163
The crystal structures and microstructures of AlN $(11\overline 2 0)$ /GaN $(11\overline 2 0)$ epitaxial films on just-cut and ±4° off-cut Al2O3 $(1\overline 1 02)$ substrates grown by metal organic chemical vapor deposition (MOCVD) are investigated using high-resolution X-ray diffractometry and transmission electron microscopy, and are compared with those of AlN $(11\overline 2 0)$ film on +4° off-cut Al2O3 $(1\overline 1 02)$ substrate. In the AlN/Al2O3(+4° off-cut) film and the AlN/GaN/Al2O3 (just-cut, ?4° off-cut) films, cracks parallel to the $[1\overline 1 00]$ AlN direction and perpendicular to the interfaces of the films and the substrates are observed. The AlN/Al2O3 and AlN/GaN interfaces exhibit low crystallinity in which moiré fringes are observed. On the other hand, in the AlN/GaN/Al2O3(+4° off-cut) film, no cracks form. The GaN layer buffers the lattice mismatch between the AlN film and the Al2O3 substrate, and moiré fringes are not observed in the GaN/Al2O3 and AlN/GaN interfaces. On the basis of these results, the effects of the interface structures on cracking are discussed. 相似文献
124.
In problems of system analysis, it is customary to treat imprecision by the use of probability theory. It is becoming increasingly clear, however, that in the case of many real world problems involving large scale systems such as economic systems, social systems, mass service systems, etc., the major source of imprecision should more properly be labeled ‘fuzziness’ rather than ‘randomness.’ By fuzziness, we mean the type of imprecision which is associated with the lack of sharp transition from membership to nonmembership, as in tall men, small numbers, likely events, etc. In this paper our main concern is with the application of the theory of fuzzy sets to decision problems involving fuzzy goals and strategies, etc., as defined by R. E. Bellman and L. A. Zadeh [1]. However, in our approach, the emphasis is on mathematical programming and the use of the concept of a level set to extend some of the classical results to problems involving fuzzy constraints and objective functions. 相似文献
125.
Kenichi Asai 《Higher-Order and Symbolic Computation》2009,22(3):275-291
In “Functional Unparsing” (J. Funct. Program. 8(6):621–625, 1998), Danvy presented a type-safe printf function using continuations and an accumulator to achieve the effect of dependent types.
The key technique employed in Danvy’s solution is the non-standard use of continuations: not all of its calls are tail calls,
i.e., it uses delimited continuations. Against this backdrop, we present three new solutions to the printf problem: a simpler
one that also uses delimited continuations but that does not use an accumulator, and the corresponding two in direct style
with the delimited-control operators, shift and reset. These two solutions are the direct-style counterparts of the two continuation-based ones. The last solution pinpoints the
essence of Danvy’s solution: shift is used to change the answer type of delimited continuations. Besides providing a new application of shift and reset, the solutions in direct style raise a key issue in the typing of first-class delimited continuations and require Danvy and
Filinski’s original type system. The resulting types precisely account for the behavior of printf. 相似文献
126.
Dispersion and electrical properties of fluorinated carbon black‐filled poly(vinylidene fluoride) (PVDF) composites were studied as a function of the fluorine content. It was found that with increasing the fluorine content carbon particles tend to stick together to form large aggregates. The percolation concentration increases to a high concentration, whereas the percolation process becomes gradual. The temperature dependence of resistivity measurements show that the fluorinated carbon black‐filled PVDF composites exhibit a high PTC intensity and a low NTC effect. These phenomena were discussed in terms of thermodynamic interactions between fluorinated carbon and the PVDF matrix. The dielectric behavior was also investigated in this study. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1063–1070, 2001 相似文献
127.
In situ measurements of the ionic conductivity were performed on polyethers, poly(ethylene oxide) (PEO) and poly(oligo oxyethylene methacrylate) (PMEO), with lithium triflate (LiCF3SO3) as crystalline and amorphous electrolytes, and at CO2 pressures up to 20 MPa. Both PEO and PMEO systems in subcritical and supercritical CO2 increased more than five fold in ionic conductivity at 40 °C composed to atmospheric pressure. The pressure dependence of the ionic conductivity for PEO electrolytes was positive under CO2, and increased by two orders of magnitude under pressurization from 0 to 20 MPa, whereas it decreases with increasing pressure of N2. The enhancement is caused by the plasticizing effect of CO2 molecules that penetrate into the electrolytes. 相似文献
128.
Chikashi Minemura Shunichi Asai Ayaka Koma Ikuko Kase-Kato Nozomi Tanaka Naoko Kikkawa Atsushi Kasamatsu Hidetaka Yokoe Toyoyuki Hanazawa Katsuhiro Uzawa Naohiko Seki 《International journal of molecular sciences》2022,23(7)
Recently, our studies revealed that some passenger strands of microRNAs (miRNAs) were closely involved in cancer pathogenesis. Analysis of miRNA expression signatures showed that the expression of miR-30e-3p (the passenger strand of pre-miR-30e) was significantly downregulated in cancer tissues. In this study, we focused on miR-30e-3p (the passenger strand of pre-miR-30e). We addressed target genes controlled by miR-30e-3p that were closely associated with the molecular pathogenesis of head and neck squamous cell carcinoma (HNSCC). Ectopic expression assays demonstrated that the expression of miR-30e-3p attenuated cancer cell malignant phenotypes (e.g., cell proliferation, migration, and invasive abilities). Our analysis of miR-30e-3p targets revealed that 11 genes (ADA, CPNE8, C14orf126, ERGIC2, HMGA2, PLS3, PSMD10, RALB, SERPINE1, SFXN1, and TMEM87B) were expressed at high levels in HNSCC patients. Moreover, they significantly predicted the short survival of HNSCC patients based on 5-year overall survival rates (p < 0.05) in The Cancer Genome Atlas (TCGA). Among these targets, SERPINE1 was found to be an independent prognostic factor for patient survival (multivariate Cox regression; hazard ratio = 1.6078, p < 0.05). Aberrant expression of SERPINE1 was observed in HNSCC clinical samples by immunohistochemical analysis. Functional assays by targeting SERPINE1 expression revealed that the malignant phenotypes (e.g., proliferation, migration, and invasion abilities) of HNSCC cells were suppressed by the silencing of SERPINE1 expression. Our miRNA-based approach will accelerate our understanding of the molecular pathogenesis of HNSCC. 相似文献
129.
H Manki S Kanba T Muramatsu S Higuchi E Suzuki S Matsushita Y Ono H Chiba F Shintani M Nakamura G Yagi M Asai 《Canadian Metallurgical Quarterly》1996,40(1-2):7-13
Disturbances in dopaminergic systems have been implicated in the etiology of mood disorders. Although genetic factors also play an important role, no major gene has been identified. We conducted an association study using the dopamine D2, D3 and D4 receptor, and transporter gene polymorphisms, comparing 101 mood-disorder patients (52 bipolar and 49 unipolar) and 100 controls. Our results suggest that there is a significant association between the dopamine D4 receptor gene and mood disorders, especially major depression, but no association between the other polymorphisms and mood disorders. Further investigations are needed to clarify the clinical significance of this association in the pathophysiology of mood disorders. 相似文献
130.
A 6-month regimen consisting of isoniazid (INH. 0.3-0.5 g).rifampicin (RFP. 0.3-0.45 g).pyrazinamide (PZA. 1.2-2.0 g) and streptomycin (SM. 0.75 g) or ethambutol (EB. 0.75-1.0 g) given for 2 month followed by isoniazid and rifampicin for 4 month is the preferred treatment for patients with fully susceptible organism, who adhere to treatment. Consideration should be given to treating all patients with directly observed treatment. 相似文献