New Era of Air Quality Monitoring from Space Kim, Jhoon; Jeong, Ukkyo; Ahn, Myoung-Hwan ...
Bulletin of the American Meteorological Society,
01/2020, Volume:
101, Issue:
1
Journal Article
Peer reviewed
Open access
The Geostationary Environment Monitoring Spectrometer (GEMS) is scheduled for launch in February 2020 to monitor air quality (AQ) at an unprecedented spatial and temporal resolution from a ...geostationary Earth orbit (GEO) for the first time. With the development of UV–visible spectrometers at sub-nm spectral resolution and sophisticated retrieval algorithms, estimates of the column amounts of atmospheric pollutants (O₃, NO₂, SO₂, HCHO, CHOCHO, and aerosols) can be obtained. To date, all the UV–visible satellite missions monitoring air quality have been in low Earth orbit (LEO), allowing one to two observations per day. With UV–visible instruments on GEO platforms, the diurnal variations of these pollutants can now be determined. Details of the GEMS mission are presented, including instrumentation, scientific algorithms, predicted performance, and applications for air quality forecasts through data assimilation. GEMS will be on board the Geostationary Korea Multi-Purpose Satellite 2 (GEO-KOMPSAT-2) satellite series, which also hosts the Advanced Meteorological Imager (AMI) and Geostationary Ocean Color Imager 2 (GOCI-2). These three instruments will provide synergistic science products to better understand air quality, meteorology, the long-range transport of air pollutants, emission source distributions, and chemical processes. Faster sampling rates at higher spatial resolution will increase the probability of finding cloud-free pixels, leading to more observations of aerosols and trace gases than is possible from LEO. GEMS will be joined by NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO) and ESA’s Sentinel-4 to form a GEO AQ satellite constellation in early 2020s, coordinated by the Committee on Earth Observation Satellites (CEOS).
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BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract To treat hypovolemic shock, fluid infusion or blood transfusion is essential to address insufficient volume. Much controversy surrounds resuscitation in hypovolemic shock. We aimed to ...identify the ideal fluid combination for treating hypovolemic shock-induced swine model, analyzing bioelectrical impedance and hemodynamics. Fifteen female three-way crossbred pigs were divided into three different groups. The three resuscitation fluids were (1) balanced crystalloid, (2) balanced crystalloid + 5% dextrose water, and (3) balanced crystalloid + 20% albumin. The experiment was divided into three phases and conducted sequentially: (1) controlled hemorrhage (1 L bleeding, 60 min), (2) resuscitation phase 1 (1 L fluid infusion, 60 min), and (3) resuscitation phase 2 (1 L fluid infusion, 60 min). Bioelectrical impedance analysis was implemented with a segmental multifrequency bioelectrical impedance analyzer. A total of 61 impedance measurements were assessed for each pig at six different frequencies in five segments of the pig. Pulse rate (PR), mean arterial pressure (MAP), stroke volume (SV), and stroke volume variation (SVV) were measured using a minimally invasive hemodynamic monitoring device. The three-dimensional graph showed a curved pattern when infused with 1 L of balanced crystalloid + 1 L of 5% dextrose water and 1.6 L of balanced crystalloid + 400 ml of 20% albumin. The 1M impedance increased in all groups during the controlled hemorrhage, and continuously decreased from fluid infusion to the end of the experiment. Only balanced crystalloid + 20% albumin significantly restored MAP and SV to the same level as the start of the experiment after the end of fluid infusion. There were no significant differences in MAP and SV from the time of recovery to the initial value of 1M impedance to the end of fluid infusion in all groups. The change and the recovery of hemodynamic indices such as MAP and SV coincide with the change and the recovery of 1M impedance. Using balanced crystalloid mixed with 20% albumin in hypovolemic shock-induced swine model may be helpful in securing hemodynamic stability, compared with balanced crystalloid single administration.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract Objectives To compare the accuracy of the commercial Fitbit Flex device (FF) with polysomnography (PSG; the gold-standard method) in insomnia disorder patients and good sleepers. Methods ...Participants wore an FF and actigraph while undergoing overnight PSG. Primary outcomes were intraclass correlation coefficients (ICCs) of the total sleep time (TST) and sleep efficiency (SE), and the frequency of clinically acceptable agreement between the FF in normal mode (FFN) and PSG. The sensitivity, specificity, and accuracy of detecting sleep epochs were compared among FFN, actigraphy, and PSG. Results The ICCs of the TST between FFN and PSG in the insomnia (ICC = 0.886) and good-sleepers (ICC = 0.974) groups were excellent, but the ICC of SE was only fair in both groups. The TST and SE were overestimated for FFN by 6.5 min and 1.75%, respectively, in good sleepers, and by 32.9 min and 7.9% in the insomnia group with respect to PSG. The frequency of acceptable agreement of FFN and PSG was significantly lower ( p = 0.006) for the insomnia group (39.4%) than for the good-sleepers group (82.4%). The sensitivity and accuracy of FFN in an epoch-by-epoch comparison with PSG was good and comparable to those of actigraphy, but the specificity was poor in both groups. Conclusions The ICC of TST in the FFN–PSG comparison was excellent in both groups, and the frequency of agreement was high in good sleepers but significantly lower in insomnia patients. These limitations need to be considered when applying commercial sleep trackers for clinical and research purposes in insomnia.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Timely administration of antibiotics is one of the most important interventions in reducing mortality in sepsis. However, administering antibiotics within a strict time threshold in all patients ...suspected with sepsis will require huge amount of effort and resources and may increase the risk of unintentional exposure to broad-spectrum antibiotics in patients without infection with its consequences. Thus, controversy still exists on whether clinicians should target different time-to-antibiotics thresholds for patients with sepsis versus septic shock.
This study analyzed prospectively collected data from an ongoing multicenter cohort of patients with sepsis identified in the emergency department. Adjusted odds ratios (ORs) were compared for in-hospital mortality of patients who had received antibiotics within 1 h to that of those who did not. Spline regression models were used to assess the association of time-to-antibiotics as continuous variables and increasing risk of in-hospital mortality. The differences in the association between time-to-antibiotics and in-hospital mortality were assessed according to the presence of septic shock.
Overall, 3035 patients were included in the analysis. Among them, 601 (19.8%) presented with septic shock, and 774 (25.5%) died. The adjusted OR for in-hospital mortality of patients whose time-to-antibiotics was within 1 h was 0.78 (95% confidence interval CI 0.61-0.99; p = 0.046). The adjusted OR for in-hospital mortality was 0.66 (95% CI 0.44-0.99; p = 0.049) and statistically significant in patients with septic shock, whereas it was 0.85 (95% CI 0.64-1.15; p = 0.300) in patients with sepsis but without shock. Among patients who received antibiotics within 3 h, those with septic shock showed 35% (p = 0.042) increased risk of mortality for every 1-h delay in antibiotics, but no such trend was observed in patients without shock.
Timely administration of antibiotics improved outcomes in patients with septic shock; however, the association between early antibiotic administration and outcome was not as clear in patients with sepsis without shock.
This study aimed to reveal the relationship between life activities and cognitive function and to evaluate the interaction between education and various leisure activities in predicting cognitive ...function. Using a cross-sectional research design with retrospective data, a total of 210 healthy Korean older adults participated and reported their years of education, working, and lifelong leisure activities. Cognitive function was measured using the Mini Mental State Examination. A hierarchical multiple regression analysis showed that education was positively associated with cognitive function, whereas working activity was not. Craft activities positively predicted cognitive function. Furthermore, education moderated the relationship between leisure activities and cognitive function. Only low-educated participants showed a decrease in cognitive function as they performed domestic chores and an increase in cognitive function as they participated in social activities and volunteering. High-educated participants showed no relation between leisure activities and cognitive function. The results of the current study suggest that the relationship between various leisure activities and cognitive function can vary based on the nature of the leisure activity and educational level. Professionals examining older adults' cognitive function should pay closer attention to educational level, as well as life styles (i.e. leisure activities), to provide appropriate interventions.
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BFBNIB, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
In February 2018, the Withdrawal of the Life-sustaining Treatment (WLST) Decision Act was legalized in Korea. Donation after circulatory death (DCD) after WLST was classified as DCD category III. We ...report the first case of successful organ donation after WLST in Korea. A 52-year-old male who experienced cerebral hemorrhage was a potential brain-dead donor with donation consent. During the first brain death examination, Babinski reflex was present, which disappeared two days later. Then, electroencephalography was performed five times at intervals of 2 to 3 days, according to the recommendation of a neurologist. The patient was transferred to the OR at 19:30 July 3, 2020. At 20:00, an intensive care unit specialist performed extubation and discontinued vasopressors. Oxygen saturation fell to < 70% in 1 minute, which signaled the beginning of functional warm ischemia. At 20:15, asystole was confirmed; after 5 minutes of “no-touch time,” circulatory death was declared. Organ procurement surgery was initiated, with surgeons performing the recipient surgery ready in the adjacent OR. Through the first successful DCD case, we expected that DCD will be actively implemented in Korea, saving the lives of patient waiting for transplantation and resolving the imbalance between organ receipt and donation.
This article introduces a 192-Gb 896-GB/s 12-high stacked third-generation high-bandwidth memory (HBM3 DRAM) with low power consumption and high-reliability traits. New design schemes and features, ...including internal low-voltage signaling, center strobe calibration, through-silicon via (TSV) auto-calibration, a symbol-correcting in-DRAM ECC, and machine-learning-based layout optimization, allow large amounts of data transfers among the vertically stacked base and core dies with limited delay mismatch or SI degradation, as well as reduced power consumption from low-voltage swings. Experimental results confirm 896-GB/s bandwidth operations at 1.0-V voltage conditions with up to 15% improved power efficiency.
Highly deformable and electrically conductive fibres with multiple functionalities may be useful for diverse applications. Here we report on a supercoil structure (i.e. coiling of a coil) of fibres ...fabricated by inserting a giant twist into spandex-core fibres wrapped in a carbon nanotube sheath. The resulting supercoiled fibres show a highly ordered and compact structure along the fibre direction, which can sustain up to 1,500% elastic deformation. The supercoiled fibre exhibits an increase in resistance of 4.2% for stretching of 1,000% when overcoated by a passivation layer. Moreover, by incorporating pseudocapacitive-active materials, we demonstrate the existence of superelastic supercapacitors with high linear and areal capacitance values of 21.7 mF cm
and 92.1 mF cm
, respectively, that can be reversibly stretched by 1,000% without significant capacitance loss. The supercoiled fibre can also function as an electrothermal artificial muscle, contracting 4.2% (percentage of loaded fibre length) when 0.45 V mm
is applied.
Dye-sensitized solar cells (DSSCs) are highly efficient and reliable photovoltaic devices that are based on nanostructured semiconductor photoelectrodes. From their inception in 1991, colloidal TiO2 ...nanoparticles (NPs) with the large surface area have manifested the highest performances and the particle size of around 20 nm is generally regarded as the optimized condition. However, though there have been reports on the influences of particle sizes in conventional DSSCs employing iodide redox electrolyte, the size effects in DSSCs with the state-of-the-art cobalt electrolyte have not been investigated. In this research, systematic analyses on DSSCs with cobalt electrolytes are carried out by using various sizes of NPs (20–30 nm), and the highest performance is obtained in the case of 30 nm sized TiO2 NPs, indicating that there is a reversed power conversion efficiency trend when compared with those with the iodide counterpart. Detailed investigations on various factorslight harvesting, charge injection, dye regeneration, and charge collectionreveal that TiO2 particles with a size range of 20–30 nm do not have a notable difference in charge injection, dye regeneration, and even in light-harvesting efficiency. It is experimentally verified that the superior charge collection property is the sole origin of the higher performance, suggesting that charge collection should be prioritized for designing nanostructured TiO2 photoelectrodes for DSSCs employing cobalt redox electrolytes.
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