5,850 research outputs found
Curved Microneedle Array-Based sEMG Electrode for Robust Long-Term Measurements and High Selectivity
Surface electromyography is widely used in many fields to infer human intention. However, conventional electrodes are not appropriate for long-term measurements and are easily influenced by the environment, so the range of applications of sEMG is limited. In this paper, we propose a flexible band-integrated, curved microneedle array electrode for robust long-term measurements, high selectivity, and easy applicability. Signal quality, in terms of long-term usability and sensitivity to perspiration, was investigated. Its motion-discriminating performance was also evaluated. The results show that the proposed electrode is robust to perspiration and can maintain a high-quality measuring ability for over 8 h. The proposed electrode also has high selectivity for motion compared with a commercial wet electrode and dry electrode.open111615Ysciescopu
Strategies for Developing Responsive Solid Waste Management in Seoul City : Institutional Arrangement
The solid waste problem surfaced with the industrialization in 1960' s in Seoul City. Before that time the solid waste was merely a trivial issue so that divisions such as Police Bureau, Social Affairs Bureau, and Health and Sanitary Bureau in the Metropolitan Government, which seem rather irrelevant, used to handle solid wastes as well as night soil in addition to their major duties. Citizens used to practice complete recycling according to the Korean tradition until 1950' s. The economic development in the Republic of Korea was accomplished mainly in the manufacturing industry, which resulted in the movement of rural population to urban areas. In 1988, the urban population reached to 78 per cent of the national total from 20 per cent three decades before. And the population is so centralized to the Capital Area that one fourth of the national total population live in Seoul City and 40 per cent in the Capital Area which includes Incheon City and Kyungki
Province which holds many satelite cities of Seoul. This urbanization together with the change in life pattern accompanied by the industrialization suddenly brought forth the solid waste problem. The solid waste generation reached to the level of 2.83 kg/capita-day, which is the world's largest, and the City spent 73 billion wons to dispose 11 million tons of wastes in 1989. Since the waste dumping is getting very difficult due to limited space available, the solid waste became one of the main urban problems the City faces at the moment
Social Environmental Education toward Sustainable Development in the East Asian Region
The East Asia with China and India included is the most populous region in the world and its economy is growing very fast to become the world's greatest economic center in near future. Because of the rapid economic development and the high economic density in this region, environmental stresses have built up very rapidly in recent years. The trans boundary air pollution, water shortage, drinking water poisoning, fresh water and marine pollution, deforestation, climatic disasters, and other environmental problems are becoming serious threats to the wellbeing of peoples in this densely populated region. In other word, the East Asia has not been going toward sustainable society. This is well indicated in the ESI(Environmental Sustainability Index) reported by the World Economic Forum in 2005. Most of the East Asian countries ranked the bottom: North Korea ranked 146th among 146 countries evaluated, Taiwan 145th, China 133rd, South Korea 122nd, and India 101st
Synthesis of horizontally aligned ZnO nanowires localized at terrace edges and application for high sensitivity gas sensor
We developed step edge decoration method for the fabrication of semiconductor ZnO nanodots and nanowires using pulsed laser deposition. We synthesized high quality ZnO nanowires with the small diameter of about 20 nm and the uniform interval of about 80 nm between each nanowire, which has a simple structure for the formation of contact electrodes. The ZnO nanowire-based sensor was prepared only with the simple process of a gold electrode formation. The ZnO nanowire-based sensor exhibited the high surface-to-volume ratio of 58.6 mu m(-1) and the significantly high sensitivity of about 10 even for the low ethanol concentration of 0.2 ppm.open115860sciescopu
Loading Dynamics of a sliding DNA clamp
Sliding DNA clamps are loaded at a ss/dsDNA junction by a clamp loader that depends on ATP binding for clamp opening. Sequential ATP hydrolysis results in closure of the clamp so that it completely encircles and diffuses on dsDNA. We followed events during loading of an E. coli beta clamp in real time by using single-molecule FRET (smFRET). Three successive FRET states were retained for 0.3 s, 0.7 s, and 9 min: Hydrolysis of the first ATP molecule by the g clamp loader resulted in closure of the clamp in 0.3 s, and after 0.7 s in the closed conformation, the clamp was released to diffuse on the dsDNA for at least 9 min. An additional single-molecule polarization study revealed that the interfacial domain of the clamp rotated in plane by approximately 88 during clamp closure. The single-molecule polarization and FRET studies thus revealed the real-time dynamics of the ATP-hydrolysis-dependent 3D conformational change of the b clamp during loading at a ss/dsDNA junction.X1156Ysciescopu
Policy Responses Towards Improving Solid Waste Management Seoul City
The Seoul City has been the capital city of the nation for about 600 years. However, the City experienced rapid growth only in recent years. The Republic of Korea remained an agricultural country until early 1960s. The rapid industrialization began with the First 5-year Economic Development Plan which started in 1962. The Seoul City grew very rapidly with the success of industrialization. The population of the City increased from 3,471 thousand in 1965 to 10,287 thousand in 1988, which occupies 23.9 per cent of the national total population. The annual population increase rate of the City during the time was 5. 07 per cent while the national average was 1. 66 per cent.
As results of rapid industrialization and urbanization, the City faced with serious urban problems such as housing, traffic congestion, environmental pollution, and others. Among them, the solid waste management issue emerged as one of the most urgent urban problems in the City. Traditionally, Korean people did not produce any wastes to be dumped collectively: all wastes were recycled in principle. Wastes were either fed to livestocks or were utilized as fertilizer. However, the citizens could no more practice recycling as the composition of wastes changed and the City became congested. The Metropolitan Government organized a department responsible for managing solid wastes only in early 1960s
Environmental Management in Korea: an Emerging Role for Industry
Two decades ago, environmental management was primarily a concern of public
interest groups, public administrators, natural resources managers and lawyers.
The corporation's environmental management program, if it existed, was a staff
function, focusing on the politics, the legal, economic and technical requirements
of regulatory law, and on governmental relations. Environmental management now extends its reach into many functions of the business corporation, from the Executive Office on down. Today. environmental management is intertwined with international trade and marketing issues. Throughout the developed world, corporations are designing corporate environmental management programs to measure up to international standards following promulgation of ISO 14000 in 1996 of final standards by the International Organization for Standardization. This paper briefly reviews some of the major environmental problems in Korea, and the significant. well-publicized initiatives recently taken by four major chaebols (conglomerates) in declaring new priorities and funding for environmental management throughout their companies. Finally. some conclusions are drawn and
questions raised about how effective these corporate environmental management
programs will be
State of Air Pollution and Policy Issues in Seoul, Republic of Korea
The Republic of Korea has experienced severe environmental problems including air pollution because of the rapid urbanization and industrialization during the last three decades. The government has taken various countermeasures in order to solve the air pollution problems. The efforts to reduce the levels of sulfur dioxide(SOβ) and total suspended particulates (TSP) have been quite successful while nitorogen oxides and ozone (Oβ) are emerging as more serious threats to the urban atmospheric environment due to the ever-increasing automobiles. The spacio-temporal analyses of the air quality using the monitoring data for the last ten years clearly revealed that the air quality changed with the urban development and countermeasure policies adopted. Future policy recommendations are made based on th analyses. As shown in Figure 1. the annual average levels of SOβ, TSP and CO decreased by 62%, 65% and 44%, respectively, over the last decade (1984-1993), while the oxidants' level (analysed as Oβ) showed 63% increase during the same period. The level of NOβ showed a slight increase in recent years
Bidirectional signaling of neuregulin-2 mediates formation of GABAergic synapses and maturation of glutamatergic synapses in newborn granule cells of postnatal hippocampus
Expression of neuregulin-2 (NRG2) is intense in a few regions of the adult brain where neurogenesis persists; however, little is understood about its role in developments of newborn neurons. To study the role of NRG2 in synaptogenesis at different developmental stages, newborn granule cells in rat hippocampal slice cultures were labeled with retrovirus encoding tetracycline-inducible microRNA targeting NRG2 and treated with doxycycline (Dox) at the fourth or seventh postinfection day (dpi). The developmental increase of GABAergic postsynaptic currents (GPSCs) was suppressed by the early Dox treatment (4 dpi), but not by late treatment (7 dpi). The late Dox treatment was used to study the effect of NRG2 depletion specific to excitatory synaptogenesis. The Dox effect on EPSCs emerged 4 d after the impairment in dendritic outgrowth became evident (10 dpi). Notably, Dox treatment abolished the developmental increases of AMPA-receptor mediated EPSCs and the AMPA/NMDA ratio, indicating impaired maturation of glutamatergic synapses. In contrast to GPSCs, Dox effects on EPSCs and dendritic growth were independent of ErbB4 and rescued by concurrent overexpression of NRG2 intracellular domain. These results suggest that forward signaling of NRG2 mediates GABAergic synaptogenesis and its reverse signaling contributes to dendritic outgrowth and maturation of glutamatergic synapses.117Ysciescopu
In vivo 3D measurement of moxifloxacin and gatifloxacin distributions in the mouse cornea using multiphoton microscopy
Moxifloxacin and gatifloxacin are fourth-generation fluoroquinolone antibiotics used in the clinic to prevent or treat ocular infections. Their pharmacokinetics in the cornea is usually measured from extracted ocular fluids or tissues, and in vivo direct measurement is difficult. In this study multiphoton microscopy (MPM), which is a 3D optical microscopic technique based on multiphoton fluorescence, was applied to the measurement of moxifloxacin and gatifloxacin distribution in the cornea. Intrinsic multiphoton fluorescence properties of moxifloxacin and gatifloxacin were characterized, and their distributions in mouse cornea in vivo were measured by 3D MPM imaging. Both moxifloxacin and gatifloxacin had similar multiphoton spectra, while moxifloxacin had stronger fluorescence than gatifloxacin. MPM imaging of mouse cornea in vivo showed (1) moxifloxacin had good penetration through the superficial corneal epithelium, while gatifloxacin had relatively poor penetration, (2) both ophthalmic solutions had high intracellular distribution. In vivo MPM results were consistent with previous studies. This study demonstrates the feasibility of MPM as a method for in vivo direct measurement of moxifloxacin and gatifloxacin in the cornea.1175Ysciescopu
- β¦