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991.
In this paper, we propose the ‘in‐air finger motion interface’, which solves a problem users face in interacting with mobile devices. The interface uses only a single small camera to track the three‐dimensional (3D) position of the user's finger. The finger region is robustly extracted by using flashing infrared light‐emitting diodes (LEDs) and by obtaining the difference image between an illuminated image and a nonilluminated image. The movement of the finger is modeled by transformation of a finger image, and its parameters are accurately estimated by iterative template matching. As a result of the evaluation, an operating area 131% larger than the size of the display and accuracy of input action of 0.6 mm in the x‐direction are realized. Finally, to investigate the effect of vibration feedback, we conducted a study and found that vibration feedback significantly reduces the average time to finish the task as well as the number of input errors. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
992.
Motion history image: its variants and applications   总被引:1,自引:0,他引:1  
The motion history image (MHI) approach is a view-based temporal template method which is simple but robust in representing movements and is widely employed by various research groups for action recognition, motion analysis and other related applications. In this paper, we provide an overview of MHI-based human motion recognition techniques and applications. Since the inception of the MHI template for motion representation, various approaches have been adopted to improve this basic MHI technique. We present all important variants of the MHI method. This paper points some areas for further research based on the MHI method and its variants.  相似文献   
993.
Objective: This study aimed to establish a rapid and simple method for isolating exosomes from raw bovine milk and to compare the quality of the isolated exosomes with those isolated by a standard method involving ultracentrifugation (UC).

Methods: To remove caseins, which are major milk proteins consisting more than 80% of milk protein (35% in human breast milk) and hamper isolation and purification of exosomes, hydrochloride (HCl) was added to milk for isoelectric precipitation (IP). The effects of acidification on morphological features, particle size distribution, surface charge, and exosome surface proteins were analyzed by electron microscopy, tunable resistive pulse sensing (TRPS), and Western blot (WB) analysis, respectively.

Results: Electron microscopy showed that some of the exosomes isolated using IP had rough surfaces; most exosomes were successfully isolated without breakage, and their morphological features were similar to those of exosomes isolated by UC. TRPS showed that their surface charge and peaks (mode) for particle size distribution did not significantly differ between both methods. WB analysis using antibodies against the exosome surface marker proteins – milk fat globule-epidermal growth factor 8 (MFG-E8) and CD63 – revealed that the structures of exosome surface proteins were not affected by adding HCl.

Conclusions: IP can be used to remove caseins to reduce operation time. This method will be useful for efficient isolation and purification of bovine milk exosomes and contribute to progression of research on health management of dairy cattle and drug delivery systems in human medicine, which require large amounts of milk exosomes.  相似文献   

994.
Aroma is an essential factor affecting the quality of tea (Camellia sinensis) products. While changes of volatile compounds during tea manufacturing have been intensively studied, the effect of environmental factors on volatile contents of fresh tea leaves has received less attention. We found that C. sinensis var. Yabukita kept in darkness by shading treatment for 3 weeks developed etiolated leaves with significantly increased levels of volatiles, especially volatile phenylpropanoids/benzenoids (VPBs). Upstream metabolites of VPBs, in particular shikimic acid, prephenic acid, and phenylpyruvic acid, showed lower levels in dark treated than in control leaves, whereas the contents of most amino acids including l-phenylalanine, a key precursor of VPBs, were significantly enhanced. In addition, analysis by ultra performance liquid chromatography-time of flight mass spectrometry, capillary electrophoresis–time of flight mass spectrometry, high performance liquid chromatography, and gas chromatography–mass spectrometry indicated that volatile and non-volatile metabolite profiles differed significantly between dark treated and untreated leaves.  相似文献   
995.
氢气渗透Nb基合金的设计及特性表征   总被引:1,自引:0,他引:1  
在Nb40Ti30Ni30合金的初生相(Nb,Ti)和共晶相连线上制作Nb-Ti-Ni合金.研究表明,上述直线上的合金由初生相和共晶相构成,氢渗透度Ф随Nb浓度和初生相(Nb,Ti)体积分数的增大而升高,氢渗透合金的Nb浓度扩展至68 mol%.Nb68Ti17Ni15合金由74%(体积分数)的初生相(Nb,Ti)和26%(体积分数)的共晶相{(Nb,Ti)+TiNi}组成,氢渗透度最大Ф673K达到4.91×10-8mol H2m-1s-1Pa-0.5,是Nb40Ti30Ni30合金的氢渗透度Ф673K的2.5倍,纯钯金的氢渗透度Ф573K的3.5倍.  相似文献   
996.
Cigarette smoking and alcohol consumption are major risk factors for lifestyle-related diseases. Although it has been reported that the combination of these habits worsens risks, the underlying mechanism remains elusive. Reactive carbonyl species (RCS) cause chemical modifications of biological molecules, leading to alterations in cellular signaling pathways, and total RCS levels have been used as a lipid peroxidation marker linked to lifestyle-related diseases. In this study, at least 41 types of RCS were identified in the lipophilic fraction of plasma samples from 40 subjects using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). Higher levels of 10 alkanals, 5 trans-2-alkenals, 1 cis-4-alkenal, and 3 alkadienals were detected in the smoking/drinking group (N = 10) as compared to those with either habit (N = 10 each) or without both habits (N = 10) in the analysis of covariances adjusted for age and BMI. The levels of 3 alkanals, 1 trans-2-alkenal, 1 alkadienal, and 1 4-hydroxy-2-alkenal in the smoking/drinking group were significantly higher than those in the no-smoking/drinking and no-smoking/no-drinking groups. These results strongly indicate that the combination of cigarette smoking and alcohol drinking synergistically increases the level and variety of RCS in the circulating blood, and may further jeopardize cellular function.  相似文献   
997.
The effect of pulsed low-direct-current (DC) electric treatment on the viability of Vibrio parahaemolyticus in artificial seawater and 3.0% (w/v) NaCl solution was studied as a function of available chlorine (AC) concentration. The amount of AC generated during the DC electric treatment increased in proportion to the amount of passed DC. The survival fraction of V. parahaemolyticus cells decreased depending on AC concentration. When the generated AC components were completely reduced in the presence of sufficient sodium thiosulfate, no inactivation of V. parahaemolyticus in the NaCl solution was observed during the DC electric treatment. Based on the AC concentration, the inactivation efficacies of the DC electric treatment of the seawater and NaCl solution were approximately 4-fold and 30-fold that of the exogenous addition of sodium hypochlorite, respectively. Fluorometric analysis using 2-[6-(4'-hydroxy)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid showed that the generation of highly reactive radical species such as hydroxyl radical in the seawater and NaCl solution occurred during the DC electric treatment. The amount of generated radical species depended on the amount of passed DC. It is concluded that pulsed low-DC electric treatment of saline solutions exerts superior inactivation efficacy against V. parahaemolyticus to sodium hypochlorite owing to the generation of radical species.  相似文献   
998.
Nonribosomal peptide (NRP) natural products are among the most promising resources for drug discovery and development, owing to their wide range of biological activities and therapeutic applications. These peptide metabolites are biosynthesized by large multienzyme machinery known as NRP synthetases (NRPSs). The structural complexity of a number of NRPs poses an enormous challenge in their synthesis. A major issue in this field is reprogramming NRPS machineries to allow the biosynthetic production of artificial peptides. NRPS adenylation (A) domains are responsible for the incorporation of a wide variety of amino acids and can be considered as reprogramming sites; therefore, advanced methods to accelerate the functional prediction and assessment of A-domains are required. This Concept article demonstrates that activity-based protein profiling of NRPSs offers a simple, rapid, and robust analytical platform for A-domains and provides insights into enzyme–substrate candidates and active-site microenvironments. It also describes the background associated with the development and application of a method to analyze endogenous NRPS machinery in its natural environment.  相似文献   
999.
We report the study on remanent vortices attached to rough boundaries in superfluid 4He after the turbulent transition. We used 2.6 µm vibrating wires with smooth surfaces and rough surfaces, a cover box and slow cooling method, in order to investigate the effect of surface roughness on the condition and the number of vortices attached to a wire. The responses of the wire with smooth surfaces show large hysteresis at the turbulent transition. This result indicates that remanent vortices attached between the wire and surrounding boundaries cause turbulence. At first sweep of driving force of the wire with rough surfaces, we also observed hysteresis as large as the case of the smooth wire: at the other sweeps, however, small hysteresis was observed. These results indicate that once turbulence is generated at a wire velocity during first sweep, vortex lines newly attach between rough surfaces of the wire, which easily cause turbulence at a low wire velocity. Therefore, we conclude that a smooth wire can reduce the number of vortices attached to a wire.  相似文献   
1000.
In order to clarify the formation condition of zinc rusts such as layered zinc hydroxynitrate (Zn5(OH)8(NO3)2·2H2O: ZHN), ZnO particles were aged with aqueous Zn(NO3)2·6H2O solution at 6–140 °C for 48 h. Further, adsorption of H2O and CO2 on ZHN was examined for simulating study of atmospheric corrosion of galvanized steel. The ZHN was formed at 6 °C and the ZnO completely disappeared, meaning the hydrolysis of ZnO particles in aqueous Zn(NO3)2·6H2O solution to recrystallize as ZHN. Increasing the aging temperature improved the crystallinity of layered structure of ZHN, showing a maximum at 85 °C. The formed ZHN was hexagonal plate-like particles. The particle size was dependent of the crystallinity of layered structure of ZHN. The specific surface area of ZHN was decreased on elevating the aging temperature, showing a minimum at 85 °C. The adsorption of H2O and CO2 was enhanced on increasing the crystallinity of layered structure of ZHN, meaning that these molecules are adsorbed not only on particle surface but also in interlayer of ZHN. These facts infer that the preferred orientation of plate-like ZHN particles leads to the formation of compact rust layer on galvanized steel and to the enhancement of corrosion resistance.  相似文献   
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