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41.
'Magic mushrooms' (MMs) are psychoactive fungi containing the hallucinogenic compounds, psilocin (1) and psilocybin (2). Since June 6, 2002, these fungi have been regulated by the Narcotics and Psychotropics Control Law in Japan. Because there are many kinds of MMs and they are sold even as dry powders in local markets, it is very difficult to identify the original species of the MMs by morphological observation. Therefore, we investigated the internal transcribed spacer (ITS) region in the ribosomal RNA gene of MMs obtained in Japanese markets to classify them by a genetic approach. Based on the size and nucleotide sequence of the ITS region amplified by PCR, tested MMs were classified into 6 groups. Furthermore, a comparison of the DNA sequences of the MMs with those of authentic samples or with those found in the databases (GenBank, EMBL and DDBJ) made it possible to identify the species of tested MMs. Analysis by LC revealed that psilocin (1) was contained at the highest level in Panaeolus cyanescens among the MMs, but was absent in the Amanita species.  相似文献   
42.
A new segment quantization method using the Lempel-Ziv algorithm is proposed, and it is applied to quantize line spectral frequency parameters in speech codec. The proposed segment quantizer can save four bits per frame, compared with the ITU-T G.729 speech codec (18 bits/frame), without degradation of subjective or objective speech quality  相似文献   
43.
The present status of microprocessor applications in various fields of electric power systems is summarized. Special attention is directed towards development trends in the protection field where microprocessor applications are expected to cope with the increasingly stringent requirements for electric power supply reliability. Also discussed are the history, roles, design philosophy and basic schemes of microprocessor-based protective relaying systems. Only recently has their application reached a practical stage after long-term study and repeated field tests.  相似文献   
44.
A new automatic cloud detection method to process the large data sets required for long-term trends in AVHRR time series images is described and tested over the Far East region. In the cloud detection method, a simple NDVI test was used to roughly separate land from ocean. After the NDVI test we carried out two tests: a visible or near-infrared test and an infrared test. Results from the cloud detection method over the Far East region are presented. In order to assess the cloud detection method, a comparison was carried out between the method presented and the Saunders and Kriebel daytime procedure using the N-Land database. We found that in general, the method presented has better performance than the Saunders and Kriebel procedure by about 0.5% to 10.5%.  相似文献   
45.
In order to realize cellular network analysis on a chip-based system, our group has been developing a patterned cell culture microdevice with pillars in an array for tapping cells into space surrounded by the pillars. The pillar structures has advantages to trap both adhesive and non-adhesive cells and to precisely control positions of cells and distances between cells for understanding effects of various cell patterns on functions of a cellular network such as cell proliferation, differentiation, and network formation. In this paper, HeLa cell cultivation with the patterned cell culture microdevice having a pillar array fabricated by dry film of thick negative photoresist SU-8 on a glass substrate was executed as a feasibility study on a cellular network analysis. The results revealed that the device performance was found to be enough to culture HeLa cells for more than 48 h. In addition, relative extensibility of blocks of multiple cells compared with single cells tapped on the device was observed. Thus, the patterned cell culture microdevice proposed here could be applicable to analysis of cellular functions.  相似文献   
46.
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass.  相似文献   
47.
Methane+ethane+1,1-dimethylcyclohexane+water system was investigated by using Raman spectroscopy and isothermal phase equilibrium measurements under four-phase (gas+aqueous+large guest species+hydrate phases) equilibrium conditions at 288.15 K. The results suggest that three kinds of hydrate structures emerge at 288.15 K in the methane+ethane+1,1-dimethylcyclohexane+water system. The hydrate structure for this system changed from structure-H to structure-I via structure-II with increase in the mole ratio of ethane to methane.  相似文献   
48.
49.
This paper presents an efficient layout method for a high-speed multiplier. The Wallace-tree method is generally used for high-speed multipliers. In the conventional Wallace tree, however, every partial product is added in a single direction from top to bottom. Therefore, the number of adders increases as the adding stage moves forward. As a result, it generates a dead area when the multiplier is laid out in a rectangle. To solve this problem, we propose a rectangular Wallace-tree construction method. In our method, the partial products are divided into two groups and added in the opposite direction. The partial products in the first group are added downward, and the partial products in the second group are added upward. Using this method, we eliminate the dead area. Also, we optimized the carry propagation between the two groups to realize high speed and a simple layout, We applied it to a 54×54-bit multiplier. The 980 μm×1000 μm area size and the 600 MHz clock speed have been achieved using 0.18 μm CMOS technology  相似文献   
50.
A major potential application for ex vivo culture of hematopoietic progenitor cells is the treatment of cytopenia following high-dose chemotherapy and hematopoietic transplantation. We have previously postulated that infusion of a sufficient number of neutrophil postprogenitor cells generated by ex vivo culture of CD34+ cells may be able to abrogate neutropenia. In this article, we describe further development of an efficient stromal-free, cytokine-dependent, static culture system for generation of these cells. Our previous studies indicated that maximal production of nucleated cells and myeloid progenitor cells from PB CD34+ cells occurred with multiple hematopoietic growth factor (HGF), notably the 6-HGF combination of interleukin (IL)-1, IL-3, IL-6, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), and stem cell factor (SCF). In the present study, we determine the contribution of each of these 6 HGF in generation of neutrophilic precursors. SCF, G-CSF, and IL-3 were found to be the most important HGF for production of neutrophilic cells. The 4-HGF combination of IL-3, IL-6, G-CSF, and SCF was optimized by performing dose-response experiments and shown to be as potent as 6 HGF for production of nascent CFU-GM and neutrophilic precursors.  相似文献   
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