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31.
Hidetoshi Nonaka 《Journal of Intelligent Information Systems》2003,21(2):105-112
This paper proposes a communication interface with eye-gaze and head gesture. Visual sensorimotor integration with eye-head cooperation is considered, especially head gesture accompanied with vestibulo-ocular reflex is used for selecting object in the screen. Eye-mark recorder and motion tracking system were used to tracking eye movement and head movement, respectively. Nonverbal response animation with eye contact was introduced in the interaction system. In identifying the head gesture, we adopted a modified dynamic programming matching method and fuzzy inference. 相似文献
32.
Erika Inoue Shiyo Minatozaki Yui Katsuta Saori Nonaka Hiroshi Nakanishi 《International journal of molecular sciences》2022,23(23)
Recently, the effects of antibacterial peptides are suggested to have therapeutic potential in Alzheimer’s disease. Furthermore, systemic treatment of Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS) induced Alzheimer’s disease-like neuropathological changes in middle-aged mice. Then, we examined whether human β-defensins (hBDs), antimicrobial peptides produced by the oral mucosa and salivary glands, can suppress Pg LPS-induced oxidative and inflammatory responses by microglia. hBD3 (1 μM) significantly suppressed Pg LPS-induced production of nitric oxide and interleukin-6 (IL-6) by MG6 cells, a mouse microglial cell line. hBD3 (1 μM) also significantly inhibited Pg LPS-induced expression of IL-6 by HMC3 cells, a human microglial cell line. In contrast, neither hBD1, hBD2 nor hBD4 failed to inhibit their productions. Furthermore, hBD3 suppressed Pg LPS-induced p65 nuclear translocation through the IκBα degradation. Pg LPS-induced expression of IL-6 was significantly suppressed by E64d, a cysteine protease inhibitor, and CA-074Me, a known specific inhibitor for cathepsin B, but not by pepstatin A, an aspartic protease inhibitor. Interestingly, hBD3 significantly inhibited enzymatic activities of recombinant human cathepsins B and L, lysosomal cysteine proteases, and their intracellular activities in MG6 cells. Therefore, hBD3 suppressed oxidative and inflammatory responses of microglia through the inhibition of cathepsins B and L, which enzymatic activities are necessary for the NF-κB activation. 相似文献
33.
K-means clustering is a very popular clustering technique, which is used in numerous applications. In the k-means clustering
algorithm, each point in the dataset is assigned to the nearest cluster by calculating the distances from each point to the
cluster centers. The computation of these distances is a very time-consuming task, particularly for large dataset and large
number of clusters. In order to achieve high performance, we need to reduce the number of the distance calculations for each
point efficiently. In this paper, we describe an FPGA implementation of k-means clustering for color images based on the filtering
algorithm. In our implementation, when calculating the distances for each point, clusters which are apparently not closer
to the point than other clusters are filtered out using kd-trees which are dynamically generated on the FPGA in each iteration
of k-means clustering. The performance of our system for 512 × 512 and 640 × 480 pixel images (24-bit full color RGB) is
more than 30 fps, and 20–30 fps for 756 × 512 pixel images in average when dividing to 256 clusters.
相似文献
Tsutomu Maruyama (Corresponding author)Email: |
34.
The tetracycline (TC) resistance gene tet(M) was monitored in bacteria isolated from Japanese coastal and off-shore marine sediments. The high rate of occurrence of TC resistant (TC(r)) bacteria (120 microg mL(-1) TC) was observed at frequency ranges between 0.0-0.08% in Tokyo Bay, 1.67-1.82% in Sagami Bay and 0.0-4.35% in the open Pacific Ocean. The tet(M) gene was PCR amplified from the TC(r) isolates, showing 127 of 209 isolates (60.8%) as positive. The rate of occurrence of tet(M) was between 32.0-96.0%, 21.1 -28.0% and 0.0-83.3% in the isolates from Tokyo Bay, Sagami Bay and the open Pacific Ocean, respectively. The tet(M) positive isolates belonged to 4 orders of bacteria. Bacillales was the most dominant order (121 strains) among tet(M) possessing bacteria, followed by Actinomycetales (three strains), Flavobacteriales (one strain) and Pseudomonadales (one strain). This indicates that tet(M) is present in various bacterial species and suggests that marine sediments are a natural reservoir of the tet(M) gene. Nucleotide sequence of the tet(M) revealed that two genotypes of tet(M) were found in the bacteria. The two genotypes were placed in genetically distant branches of the phylogenetic tree, suggesting that the two tet(M)s have different origins. 相似文献
35.
Atsushi Okuro Hiroyuki Tomita Tsutomu Hihara 《International journal of remote sensing》2014,35(14):5394-5410
In this study, eight global sea surface temperature (SST) products for 2009 are compared to clarify their characteristics. The median of eight daily values, the Ensemble Median as Reference Product (EMRP), is used as a reference product for inter-comparison. The results show that the absolute value of mean differences and the value of root mean square (RMS) differences are higher in single-microwave products such as Advanced Microwave Scanning Radiometer for the Earth observing system (AMSR-E), Tropical Rainfall Measuring Mission Microwave Imager (TMI), and WindSat, than in products such as MicroWave Optimally Interpolated SST (MWOI), Merged satellite and in situ data Global Daily SST (MGD), and Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) constructed by merging several SST data. It is of note that the characteristics of SST products depend on the type of SST used within the product, rather than the data source used. A comparison of SST products was also conducted using EMRP and data observed by moored buoys. The results show that only AMSR-E has a warm bias (+0.06°C) while other products have a cool bias (maximum value ?0.10°C). The RMS error of TMI is the highest (0.57°C), and that of EMRP the lowest (0.28°C). Furthermore, the temporal variability between the data in each SST product was compared to those observed by the Kuroshio Extension Observatory (KEO) buoy. Results show that the temporal variability of EMRP corresponds well to that of buoy data, and that the RMS error of EMRP is lower than that of the other SST products. 相似文献
36.
This paper proposes the “Substitute Interface” to utilize the flat surfaces of objects around us as part of an ad hoc mobile device. The substitute interface is established by the combination of wearable devices such as a head-mounted display with camera and a ring-type microphone. The camera recognizes which object the user intends to employ. When the user picks up and taps the object, such as a notebook, a virtual display is overlaid on the object, and the user can operate the ad hoc mobile device as if the object were part of the device. Display size can be changed easily by selecting a larger object. The user’s pointing/selection action is recognized by the combination of the camera and the ring-type microphone. We first investigate the usage scene of tablet devices and create a prototype that can operate as a tablet device. Experiments on the prototype confirm that the proposal functions as intended. 相似文献
37.
Isotactic polypropylene filled with various contents of multi‐walled carbon nanotubes (MWCNTs) were fabricated by the injection molding technique and then rolled at room temperature. The unrolled samples (URS) and rolled samples (RS) were characterized by X‐ray diffraction studies, scanning electron microscopy, mechanical and micromechanical tests and differential thermal analyses. Although the URS exhibit the lamellar α‐crystal with a*‐axis orientation, the RS show the same crystals with both a*‐ and c‐axis orientation, which is explained by interlamellar and intralamellar slips and lamellar destruction. Scanning electron micrographs display distinct surface morphological features for both URS and RS. While the tensile strength of RS is higher than that of URS, the Young's modulus (Y) is found to be lower than that of URS. Anisotropy in microharness (H) parallel and perpendicular to the rolled direction has been detected, although H for both samples increases with increasing MWCNT contents. The average relationship H/Y ≈ 0.18 as estimated for URS is closer to the predicted value of 0.10 for polymers than the H/Y ≈ 0.22 obtained for RS. The lamellar thickness for URS increases with increase of MWCNT content and that for RS decreases, as evaluated from both differential thermal analyses and X‐ray diffraction data. Copyright © 2011 Society of Chemical Industry 相似文献
38.
A generation method of artificial fluctuation data of wind power output considering smoothing effect
To use realistic wind power fluctuation data is important in simulating frequency change of power systems. It is well known that the smoothing effect must be taken into account when generating the artificial wind power output. Therefore, this paper proposed a new method to generate fluctuation waveform considering smoothing effect based on random number to fulfill the correlation among multiple sites and autoregression model. The effectiveness of the proposed method was tested by using practical wind speed data measured in Tohoku district. 相似文献
39.
40.
The Role of a Nonribosomal Peptide Synthetase in l‐Lysine Lactamization During Capuramycin Biosynthesis
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Dr. Xiaodong Liu Yuanyuan Jin Zheng Cui Dr. Koichi Nonaka Satoshi Baba Dr. Masanori Funabashi Dr. Zhaoyong Yang Dr. Steven G. Van Lanen 《Chembiochem : a European journal of chemical biology》2016,17(9):804-810
Capuramycins are one of several known classes of natural products that contain an l ‐Lys‐derived l ‐α‐amino‐?‐caprolactam (l ‐ACL) unit. The α‐amino group of l ‐ACL in a capuramycin is linked to an unsaturated hexuronic acid component through an amide bond that was previously shown to originate by an ATP‐independent enzymatic route. With the aid of a combined in vivo and in vitro approach, a predicted tridomain nonribosomal peptide synthetase CapU is functionally characterized here as the ATP‐dependent amide‐bond‐forming catalyst responsible for the biosynthesis of the remaining amide bond present in l ‐ACL. The results are consistent with the adenylation domain of CapU as the essential catalytic component for l ‐Lys activation and thioesterification of the adjacent thiolation domain. However, in contrast to expectations, lactamization does not require any additional domains or proteins and is likely a nonenzymatic event. The results set the stage for examining whether a similar NRPS‐mediated mechanism is employed in the biosynthesis of other l ‐ACL‐containing natural products and, just as intriguingly, how spontaneous lactamization is avoided in the numerous NRPS‐derived peptides that contain an unmodified l ‐Lys residue. 相似文献