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1.
AMIA Annu Symp Proc ; 2020: 697-706, 2020.
Article in English | MEDLINE | ID: mdl-33936444

ABSTRACT

Due to the global spreading of the COVID-19 virus, countries all over the world are faced with the need to conduct centralized quarantine or home quarantine for "persons who have been in contact with individuals diagnosed with the COVID-19 virus" and "visitors who have travel histories via COVID-19 hot zones". We have presented the community home quarantine service platform design that was utilized in Nanjing, China when the first wave of citizens returns to work after the Chinese New Year holidays on 10th Feb 2020. The main functions of the home quarantine monitoring system include (1) community grid management,(2) GPS positioning application in home isolation movement management,(3) Bluetooth body temperature patch data transmission integration, (4) health assessment scale (physical and mental health state) and (5) multilingual language options.


Subject(s)
COVID-19/prevention & control , Pandemics/prevention & control , Quarantine , Telemedicine , China , Humans , Mental Health , Monitoring, Physiologic , Public Health , Quarantine/methods , Quarantine/organization & administration , SARS-CoV-2 , Travel
2.
Adv Mater ; 31(3): e1806268, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30484923

ABSTRACT

Aqueous ion-solid interfacial interactions at an electric double layer (EDL) are studied in various research fields. However, details of the interactions at the EDL are still not fully understood due to complexity induced from the specific conditions of the solid and liquid parts. Several technical tools for ion-solid interfacial probing are experimentally and practically proposed, but they still show limitations in applicability due to the complicated measurements. Recently, an energy conversion device based on ion dynamics (called ionovoltaic device) was also introduced as another monitoring tool for the EDL, showing applicability as a novel probing method for interfacial interactions. Herein, a monitoring technique for specific ion adsorption (Cu2+ and Pb2+ in the range of 5 × 10-6 -1000 × 10-6 m) in the solid-liquid interface based on the ionovoltaic device is newly demonstrated. The specific ion adsorption and the corresponding interfacial potentials profiles are also investigated to elucidate a working mechanism of the device. The results give the insight of molecular-level ion adsorption through macroscopic water-motion-induced electricity generation. The simple and cost-effective detection of the device provides an innovative route for monitoring specific adsorption and expandability as a monitoring tool for various solid-liquid interfacial phenomena that are unrevealed.

3.
Angew Chem Int Ed Engl ; 57(8): 2091-2095, 2018 02 19.
Article in English | MEDLINE | ID: mdl-29277950

ABSTRACT

The development of energy-conversion devices using water movement has actively progressed. Ionovoltaic devices, which are driven by ion dynamics, show ion specificity by which different ions with identical charges show different output performance. However, the ion specificity remains poorly understood because the influence of the ion species on generated electric signals is not elucidated. The ion specificity in electric signals induced by flowing water droplet was investigated in terms of its relationship with the potential profile across the solid-liquid interface.

4.
J Am Chem Soc ; 139(32): 10968-10971, 2017 08 16.
Article in English | MEDLINE | ID: mdl-28753025

ABSTRACT

Recently, various energy transducers driven by the relative motion of solids and liquids have been demonstrated. However, in relation to the energy transducer, a proper understanding of the dynamic behavior of ions remains unclear. Moreover, the energy density is low for practical usage mainly due to structural limitations, a lack of material development stemming from the currently poor understanding of the mechanisms, and the intermittently generated electricity given the characteristics of the water motion (pulsed signals). Here, we verify a hypothesis pertaining to the ion dynamics which govern the operation mechanism of the transducer. In addition, we demonstrate enhanced energy transducer to convert the mechanical energy of flowing water droplets into continuous electrical energy using an electrolyte-insulator-semiconductor structure as a device structure. The output power per droplet mass and the ratio of generated electric energy to the kinetic energy of water drops are 0.149v2 mW·g-1·m-2·s2 and 29.8%, respectively, where v is the speed of the water droplet.

5.
ACS Appl Mater Interfaces ; 8(37): 24579-84, 2016 Sep 21.
Article in English | MEDLINE | ID: mdl-27564593

ABSTRACT

The recent trend of energy-harvesting devices is an adoption of fabric materials with flexible and stretchable according to the increase of wearable electronics. But it is a difficult process to form a core structure of dielectric layer or electrode on fabric materials. In particular, a fabric-based energy-harvesting device in contact with water has not been studied, though there are many challenging issues including insulation and water absorption in a harsh environment. So we propose an effective method to obtain an electrical energy from the water contact using our new fabric energy harvesting device. Our water motion active transducer (WMAT) is designed to obtain electrical energy from the variable capacitance through the movement and contact of water droplet. In this paper, we succeeded in generating an electrical energy with peak to peak power of 280 µW using a 30 µL of water droplet with the fabric WMAT device of 70 mm × 50 mm dimension. Furthermore, we specially carried out spray-coating and transfer processes instead of the conventional spin-coating process on fabric materials to overcome the limitation of its uneven morphology and porous and deformable assembly.

6.
Sci Rep ; 5: 15695, 2015 Oct 29.
Article in English | MEDLINE | ID: mdl-26511626

ABSTRACT

Flows in small size channels have been studied for a long time over multidisciplinary field such as chemistry, biology and medical through the various topics. Recently, the attempts of electricity generation from the small flows as a new area for energy harvesting in microfluidics have been reported. Here, we propose for the first time a new fluidic electricity generator (FEG) by modulating the electric double layer (EDL) with two phase flows of water and air without external power sources. We find that an electric current flowed by the forming/deforming of the EDL with a simple separated phase flow of water and air at the surface of the FEG. Electric signals between two electrodes of the FEG are checked from various water/air passing conditions. Moreover, we verify the possibility of a self-powered air slug sensor by applying the FEG in the detection of an air slug.

7.
J Phys Chem Lett ; 6(4): 745-9, 2015 Feb 19.
Article in English | MEDLINE | ID: mdl-26262497

ABSTRACT

In this Letter, we discuss the surface, ionic properties, and scale-up potential of an active transducer that generated electricity from natural water motion. When a liquid contacts a solid surface, an electrical double layer (EDL) is always formed at the solid/liquid interface. By modulating the EDL, the active transducer could generate a peak voltage of ∼3 V and a peak power of ∼5 µW. Interestingly, there were specific salinities of solution droplets that showed maximum performance and different characteristics according to the ions' nature. Analyzing the results macroscopically, we tried to figure out the origins of the active transducing precipitated by ions dynamics. Also, we demonstrated the scale-up potential for practical usage by multiple electrode design.

8.
Cancer Res Treat ; 47(4): 638-44, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25761490

ABSTRACT

PURPOSE: There is no regimen that is strongly recommended for more than second-line treatment. We investigated the efficacy and safety of platinum/vinorelbine as more than second-line treatment. MATERIALS AND METHODS: We selected patients with advanced non-small cell lung cancer (NSCLC) who received treatment with platinum/vinorelbine at Chungnam National University Hospital from August 2001 to December 2013. The primary end point was the response rate, and secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity. RESULTS: Thirty-five patients were enrolled. Response rate was 22.9% (complete response, 0 patients [0%]; partial response, eight patients [22.9%]; stable disease, 10 patients [28.6%]; progressive disease, 14 patients [40.0%]). A significantly higher response rate was observed for patients who had responded to previous chemotherapy than for those who did not (34.8% [8/23] vs. 0% [0/12], p=0.020). The median PFS was 4 months (range, 1 to 21 months). Patients with adenocarcinoma and non-smokers had a significantly longer PFS than patients with non-adenocarcinoma and smokers (5 months vs. 2 months, p=0.007; 4.5 months vs. 2 months, p=0.046, respectively). The median OS was 10 months (range, 1 to 41 months). Patients with good performance status and non-smokers had a significantly longer OS than patients with poor performance status and smokers (14 months vs. 4 months, p=0.02; 18.5 months vs. 6 months, p=0.049, respectively). The main serious adverse event (grade 3 or 4) was neutropenia (15 events, 13.3%) in a total of 113 cycles. CONCLUSION: Platinum/vinorelbine was effective as more than second-line chemotherapy, and the toxicity was tolerable, in patients with advanced NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/drug therapy , Platinum/adverse effects , Platinum/pharmacology , Vinblastine/analogs & derivatives , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols , Disease-Free Survival , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Platinum/administration & dosage , Retrospective Studies , Vinblastine/administration & dosage , Vinblastine/adverse effects , Vinblastine/pharmacology , Vinorelbine
9.
J Korean Med Sci ; 28(2): 200-4, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23400269

ABSTRACT

To determine the approximate incidence and clinical features of pernicious anemia in a Korean population, we retrospectively analyzed clinical data for patients with pernicious anemia who were diagnosed between 1995 and 2010 at five hospitals in Chungnam province. Ninety-seven patients were enrolled, who accounted for 24% of patients with vitamin B(12) deficiency anemia. The approximate annual incidence of pernicious anemia was 0.3 per 100,000. The median age was 66 (range, 32-98) yr, and the male/female ratio was 1.25. Anemia-associated discomfort was the most common symptom (79.4%), followed by gastrointestinal and neurological symptoms (78.4% and 38.1%, respectively). Pancytopenia was found in 36 patients (37.1%), and autoimmune disorders were found in 15 patients (15.5%). Antibody to intrinsic factor was detected in 62 (77.5%) of 80 patients examined, and antibody to parietal cells was detected in 35 (43.2%) of 81 patients examined. Of the 34 patients who underwent tests for Helicobacter pylori, 7 (12.5%) were positive. The anemia-associated and gastrointestinal symptoms resolved completely in all patients after intramuscular injection of cobalamin, whereas neurological symptoms remained in some. In conclusion, pernicious anemia is less frequent in Koreans than in Western populations; however, the clinical features of this disorder in Koreans do not differ from those of Western cases.


Subject(s)
Anemia, Pernicious/diagnosis , Adult , Aged , Anemia, Pernicious/complications , Anemia, Pernicious/epidemiology , Asian People , Autoimmune Diseases/complications , Autoimmune Diseases/epidemiology , Female , Gastrointestinal Diseases/complications , Gastrointestinal Diseases/drug therapy , Gastrointestinal Diseases/epidemiology , Helicobacter Infections/diagnosis , Helicobacter pylori , Humans , Isoantibodies/blood , Male , Middle Aged , Nervous System Diseases/complications , Nervous System Diseases/epidemiology , Parietal Cells, Gastric/immunology , Republic of Korea/epidemiology , Retrospective Studies , Vitamin B 12/blood , Vitamin B 12/therapeutic use
10.
J Colloid Interface Sci ; 386(1): 135-40, 2012 Nov 15.
Article in English | MEDLINE | ID: mdl-22909963

ABSTRACT

Titania nanoparticles were modified by free-radical graft polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) at the particle surface, resulting in the formation of a 1-2 nm thick polymer brush. The zwitterionic nature of the polymer layer suggests that the suspension stability is a delicate function of pH, as well as volume fraction, salt concentration and the presence of charged or un-charged additives which may act as depletants or to screen charge interactions in the system. In this context, we characterized the suspension rheology as a function of volume fraction, pH, ionic strength and the concentration of surfactants in the suspension. Near-neutral pH, the brush layer is effective in stabilizing particles against aggregation with Newtonian behavior observed for volume fractions approaching 14%. Flocculation of particles and an onset of shear-thinning behavior was observed on decreasing pH from near-neutral. Conversely, suspension stability was maintained on increasing pH from near-neutral. Likewise, flocculation could be quickly induced by the addition of salt and cationic surfactant in small amounts, but the suspensions displayed greater stability to anionic and non-ionic surfactant additives. These results have important implications for the successful formulation of complex fluids employing zwitterionic colloids.

11.
Korean Circ J ; 42(1): 58-61, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22363386

ABSTRACT

Stent fracture is a complication following implantation of drug eluting stents and is recognized as one of the risk factors for in-stent restenosis. We present the first case of successfully managing a stent fracture and subsequent migration of the fractured stent into the ascending aorta that occurred during repeat revascularization for in-stent restenosis of an ostium of saphenous vein graft after implantation of a zotarolimus-eluting stent. Although the fractured stent segment had migrated into the ascending aorta with a pulled balloon catheter, it was successfully repositioned in the saphenous vein graft using an inflated balloon catheter. Then, the fractured stent segment was successfully connected to the residual segment of the zotarolimus-eluting stent by covering it with an additional sirolimuseluting stent.

12.
Korean J Hematol ; 46(2): 128-34, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21747886

ABSTRACT

BACKGROUND: Hypocellularity of bone marrow (BM), not associated with significant dyshematopoiesis, is often found in patients with isolated thrombocytopenia, but its clinical implications have not been studied. We prospectively studied the clinical features and natural history of these patients. METHODS: Adults with isolated thrombocytopenia (platelet counts <100×10(9)/L) in the absence of dyshematopoiesis, cytogenetic abnormalities, or megakaryocytic hyperplasia and who had BM hypocellularity (below 30% in patients aged less than 60 years; below 20% in patients aged 60 years or more) were enrolled at Chungnam National University Hospital between January 2002 and December 2006. They were monitored regularly for changes in platelet counts or development of additional cytopenia. RESULTS: Twenty patients (17 men and 3 women) were enrolled in the study. The median age was 29 years (range, 18-70 years). At initial presentation, the platelet counts ranged from 12×10(9)/L to 99×10(9)/L (median, 63×10(9)/L) and were >50×10(9)/L in 16 patients (80%). BM cellularity ranged from 5% to 25% (median, 15%) and was ≤10% in 6 patients (30%). During the median 48-month follow-up (range, 12-90 months), platelet counts of 3 of the 20 patients recovered to normal levels (>150×10(9)/L) after 12, 56 and 66 months. Three patients developed pancytopenia after 11, 70 and 90 months. Two patients were consistent with moderate aplastic anemia, and 1 was confirmed as having refractory cytopenia with multilineage dysplasia. In the remainder of the patients, platelet counts remained unchanged. CONCLUSION: Isolated thrombocytopenia accompanied by hypocellular marrow encompasses a group of heterogeneous conditions.

13.
Korean J Hematol ; 46(4): 244-52, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22259630

ABSTRACT

BACKGROUND: Antagonists of CXC chemokine receptor 4 (CXCR4), including AMD3100, induce peripheral mobilization of hematopoietic stem cells and have been approved for clinical use. We explored whether the CXCR4 antagonists affected the survival and proliferation of myeloid leukemia cells in vitro. METHODS: The effects of CXCR4 antagonists AMD3100 and T140 on the survival and proliferation of myeloid leukemia cell lines (U937, HL-60, MO7e, KG1a, and K562) as well as CD34(+) cells obtained from patients with AML and CML were analyzed by flow cytometry by using annexin V and a colorimetric cell proliferation assay. RESULTS: AMD3100, but not T140, stimulated the proliferation of leukemia cells in vitro in a dose-dependent manner for up to 5 days (~2-fold increase at a concentration of 10(-5) M), which was not abrogated by pretreatment of the cells with pertussis toxin, but was attenuated by RNAi knockdown of CXCR7 transcripts. In contrast, AMD3100 induced a marked decrease in the cell numbers after 5-7 days. AMD3100, but not T140, induced phosphorylation of MAPK p44/p42. AMD3100 increased the number and size of leukemia cell colonies and reduced cell apoptosis during the first 5-7 days of incubation, but the phenomena were reversed during the later period of incubation. CONCLUSION: The effects of CXCR4 antagonists on the proliferation of myeloid leukemia cells are not uniform. AMD3100, but not T140, exerts dual effects, initially enhancing and subsequently inhibiting the survival and proliferation of the cells in vitro.

14.
Colloids Surf B Biointerfaces ; 38(1-2): 35-40, 2004 Oct 10.
Article in English | MEDLINE | ID: mdl-15465302

ABSTRACT

In this work, the biodegradable poly(epsilon-caprolactone) (PCL)/poly(ethylene glycol) (PEG) microcapsules were prepared in the presence of SiO(2) and fragrant oil using emulsion solvent evaporation method. And SiO(2) was chemically treated in 30 wt.% hydrochloric acid and sodium hydroxide. The effect of chemical treatment on SiO(2) surfaces was studied in terms of pH, acid-base value, and N(2)/77 K gas adsorption. Image analyzer and scanning electron microscope (SEM) were used to observe the shape and surface change of the prepared microcapsules. And the variation of surface free energy of microcapsules was characterized by contact angles. The results showed that the average diameter, surface free energy, and fragrant oil release rate of microcapsules were increased with increasing the PEG ratio. Also, it was found that in the case of basic treated SiO(2), the fragrant oil adsorption capacity and release rate were decreased due to the decrease of specific surface area or the increase of acid-base interactions between basic SiO(2) and acidic fragrant oil.


Subject(s)
Capsules/chemistry , Oils/chemistry , Polyesters/chemistry , Polyethylene Glycols/chemistry , Silicon Dioxide/chemistry , Adsorption , Emulsions , Solvents/chemistry , Surface Properties
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