• Journal of Korean Society of Water and Wastewater
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• v.28 no.2
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• pp.151-160
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• 2014

Capacitive deionization(CDI) has many advantages over other desalination technologies due to its low energy consumption, less environmental pollution and relative low fouling potential. The objectives of this study are evaluate the performance of CDI which can be used for dissolved salts removal from sewage. To identify ion selectivity of nitrate and phosphate in multiionic solutions and adsorption/desorption performance related to applied potential, a series of laboratory scale experiments were conducted using a CDI unit cell with activated carbon electrodes. The CDI process was able to achieve more than 75 % TDS and $NO_3{^-}$, $NH_4{^+}$ removals, while phosphate removal was 60.8 % and is inversely related in initial TDS and $HCO_3{^-}$ concentration. In continuous operation, increasing the inner cell pressure and reduction of TDS removal ability were investigated which are caused by inorganic scaling and biofouling. However a relative mild cleaning solution(5 % of citric acid for calcium scaling and 500 mg/L of NaOCl for organic fouling) restored the electrochemical adsorption capacity of the CDI unit to its initial level.

• Clinical and Experimental Pediatrics
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• v.58 no.2
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• pp.64-68
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• 2015

Purpose: The purpose of this study was to investigate the importance of initial screening tests for depression and anxiety disorders in children with headache. In addition, this study evaluated whether the Children's Depression Inventory (CDI) and Revised Children's Manifest Anxiety Scale (RCMAS) are suitable for screening symptoms of depression and anxiety. Methods: A retrospective chart review was conducted of 720 children aged 7-17 years who had visited a pediatric neurology clinic for headaches and were referred to a pediatric psychiatric clinic for psychiatric symptoms from January 2010 to December 2011. All patients completed the CDI and RCMAS. Among them, charts of patients with clinically significant total scores (cutoff>15) for psychiatric symptoms, as defined by the CDI and RCMAS scoring scales, were reviewed. Results: Nineteen patients had headaches and clinically significant total scores for psychiatric symptoms. The mean age at headache diagnosis was 11.7 years, and 57% were male. Mean duration of headache was 11.5 months. Two point eight percent of the patients were diagnosed with psychiatric disorders including major depression (1.7%), generalized anxiety disorder (1.1%), and bipolar disorder (0.1%). Four patients (0.6%) were diagnosed with attention deficit/hyperactivity disorder (ADHD). Total mean CDI and RCMAS scores of patients referred to the psychiatric clinic were 18.8 and 22.2, respectively. There was no correlation between CDI or RCMAS total scores and headache frequency, duration, or severity. Conclusion: We recommend that all patients with headache should be screened for depression and anxiety by CDI and RCMAS scores.

• Journal of Nutrition and Health
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• v.46 no.1
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• pp.34-49
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• 2013

The purpose of this study was to evaluate nutrition intake and diet quality according to beverage consumption status in elementary school students (ESS = 317), middle-school students (MSS = 431), and high-school students (HSS = 373). We analyzed data from the combined 2007-2008 Korean National Health and Nutrition Examination Survey (KNHANES). Subjects were divided into two groups, the non-beverage group and the beverage intake group according to beverage intake from drink types (fruit-vegetable drinks, carbonated drinks, and dairy drinks). Intake of dairy drinks was significantly lower in the carbonated drinks intake (CDI) group, compared with the non-CDI group in the MSS group. Intake of vitamin C was significantly higher in the fruit-vegetable drinks intake (FVDI) group, compared with the non-FVDI group. Intake of Ca and P was significantly lower in the CDI group, compared with the non-CDI group. Intake of vitamin B2, Ca, and P was significantly higher in the dairy drinks intake (DDI) group, compared with the non-DDI group. The mean adequacy ratio (MAR) of the FVDI group and the DDI group was significantly higher than those of the non-FVDI and non-DDI group. In diet quality, nutrients less than 1 on the index of nutritional quality (INQ) were significantly higher in the CDI group, compared with the non-CDI group. In conclusion, consumption of carbonated drinks dropped the diet quality however, consumption of fruit-vegetable drinks and dairy drinks improved the diet quality of micronutrients. Therefore, a well-planned diet must be used for replacement of nutrients lost from excessive intake of carbonated beverages during a time in life when growth is especially prominent.

• Biomedical Science Letters
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• v.26 no.3
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• pp.210-216
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• 2020

The purpose of this study was to evaluate GDH & Toxin (GDT) tests for the identification of the presence of Clostridioides difficile (C. difficile) as well as to detect whether any toxin was present in the feces of patients suspected of diarrhea associated with C. difficile. Data related to the results of toxin and culture (TC) tests and GDT tests conducted on patients with diarrhea and suspected CDI between January 2017 and august 2018, positive test rates, patient ages and sexes, whether the patients were hospitalized, and turnaround time (TAT) were analyzed retrospectively. Of the 7,554 total tests conducted for CDI diagnosis, 1,010 TC tests (14.9%) were positive, while 92 GDT tests (12.0%) were positive. Of these positive cases, 815 (80.7%) identified through TC test and 80 (87%) identified through GDT test were inpatients. also, among the patients with positive test results, 497 (49.2%) diagnosed through TC test and 45 (48.9%) diagnosed through GDT test were aged 61 years or older. The total time required to complete a TC test was 83.6 hours, while the time required for a GDT test was 11.2 hours, equating to an approximately three-day difference between the two tests. The detection of toxin-producing C. difficile is important in CDI diagnosis, but the commonly used Enzymeimmunoassay (EIA) toxin tests with low sensitivity result in delayed CDI diagnosis time. Therefore, primary screening tests for CDI diagnosis using the GDT method and secondary tests using additional methods are considered most effective.

• Childhood Kidney Diseases
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• v.24 no.1
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• pp.42-46
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• 2020

Disturbances in water and salt balances are relatively common in children after brain tumor surgery. However, the coexistence of different diseases of water and sodium homeostasis is challenging to diagnose and treat. The coexistence of combined central diabetes insipidus (CDI) and cerebral salt wasting syndrome (CSWS) is rare and may impede accurate diagnosis. Herein, we report the case of an 18-year-old girl who underwent surgery for a germinoma and who presented prolonged coexistence of CDI and CSWS. The patient was diagnosed with panhypopituitarism with CDI at presentation and was treated with hydrocortisone, levothyroxine, and desmopressin. Postoperatively, she developed polyuria of more than 3L/day, with a maximum daily urine output of 7.2 L/day. Her serum sodium level decreased from 148 to 131 mEq/L. Polyuria was treated with desmopressin at incremental doses, and hyponatremia was managed with fluid replacement. At 2 months after surgery, she presented with hyponatremia-induced seizure. Polyuria and hyponatremia combined with natriuresis indicated CSWS. Treatment with fludrocortisone were initiated; then, her electrolyte level gradually normalized. CSWS is self-limiting and generally resolves within 2 weeks. However, the patient in this study still required treatment with vasopressin and fludrocortisone at 16-months after surgery. Hyponatremia in a patient with CDI may be erroneously interpreted as inadequate CDI control or syndrome of inappropriate antidiuretic hormone secretion, leading to inappropriate treatment. The identification of the potential combination of CDI and CSWS is important for early diagnosis and treatment.

• Membrane Journal
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• v.30 no.5
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• pp.342-349
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• 2020

In this study, we suggest conditions to reduce fouling in capacitive deionization (CDI) caused by alginic acid sodium salt, one of the most common fouling-causing substances in natural water and wastewater management. First, NaCl is used as feed material, which is selected as the control of the experiment. As expected, fouling phenomena is not observed from NaCl. On the other hand, when alginic acid sodium salt is added to the inlet, the fouling phenomena can be observed. In order to minimize the fouling phenomena, the feed concentration of alginic acid sodium salt, applied potential during desorption process, and duration of applied potential to our CDI cell are controlled. With 7 mg/L of feed stream concentration, CDI performed using 1.2 V for 1 min during adsorption followed by desorption with -2 V for 1 min exhibited the highest alginic acid salt removal efficiency reaching 50.07%.

• Journal of the Korean Electrochemical Society
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• v.7 no.1
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• pp.38-43
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• 2004

Porous carbon aerogel-silica gel composite materials were used as the electrodes of capacitive deionization(CDI) process, which were prepared by a paste rolling method. The electrochemical parameters such at current values, coulombs af a function of cycle, and CDI efficiencies were investigated for 10th and 100th cycles in 1,000ppm NaCl solution. Carbon aerogel-silica gel composite electrodes showed good wet-ability and higher mechanical strengths even under the NaCl solutions as well. In our experimented runs, all of the composite electrodes also are showed good cycle-ability without destroy of active material during cycles and decreased manufacturing times by $50\%$. Conclusively, the adding of silica gel powder to carbon aerogel leads to the effective performance of CDI process due to effective utilization of active materials by increasing the wet-ability and mechanical hardness.

• Journal of the Korean Electrochemical Society
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• v.17 no.1
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• pp.37-43
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• 2014

In this study, capacitive deionization (CDI) was introduced for desalination of mining water. Ion-exchange polymer coated carbon electrodes (IEE) were used in CDI to desalt mining water. The CDI performance using the IEE for desalination of mining water was carried out and then was compared with that using general carbon electrodes without ion-exchange polymer coating (GE). Moreover, to investigate the effect of the concentration of influent solutions on CDI performance, the CDI performance using the IEE for desalination of brackish water (NaCl 200 ppm) was also performed and analyzed. As a result, the higher salt removal efficiency, rate and the lower energy consumption in the CDI process using the IEE and mining water were obtained compared with those using the GE and mining water. It is mainly due to higher non-Faradaic current, low ohmic resistance of the influent, overlapping effect of electric double layers in micropore of the electrode. In addition, the CDI process using the IEE and brackish water shows much higher salt removal efficiency and lower salt removal rate than that using the IEE and mining water. This results from the lower concentration (i.e., higher ohmic resistance) and salt amount of the influent.

• Journal of Oral Medicine and Pain
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• v.18 no.2
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• pp.131-147
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• 1993

To evaluate the contribution of head/neck posture to signs/symptoms of craniomandibular disorder(CMD), the author clinically, cephalo-metrically, analyzed craniomandibular index (CMI), clinical dysfunction index(CDI), occlusal index(OI) and head posture, cervical spine, cervicovertebral anatomy, craniofacial variables from 30 CMD patients and control. And the author analyzed difference between patients and control, and the correlation between CMI, CDI and head posture, cervical spine, cervicovertebral anatomy, craniofacial variables in CMD patients and control. The obtained results were as follows : 1. There was very high significant correlation between CMI and CDI(r=0.8969, p<0.01). 2. There was significant difference between patients and control in head/neck posture, head/neck anatomy(p<0.05). 3. There was significant correlation between CMI, CDI and head posture, cervical spine, cervicovertebral anatomy, craniofacial variables(p<0.05). 4. There was more significant correlation between DI and head/neck posture, head/neck anatomy than between PI and head/neck posture, head/neck anatomy in CMD patients(p<0.05)

• Journal of computational fluids engineering
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• v.15 no.1
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• pp.31-36
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• 2010

In the present study, computations for flow fields inside the CDI unit cells with electrodes and spacers have been made to evaluate their performance. Three types of unit cells that include a planar type, a serpentine channel type, and a spiral wound type were considered and their flow characteristics were compared. From the computational results, it is found that the serpentine channel type has a large flow resistance and can not guarantee the outflow flux for industrial applications. On the other hand, the planar type can sustain a large enough outflow flux but it's efficiency is low for the electrode-use because of the non-uniform velocity distribution inside the cell and dead zones in every corner. Finally, The spiral wound type has not only a large outflow flux as much as the planar type has, but also a high efficiency for the electrode-use because of uniform velocity distribution. From this comparison, we can expect that the spiral wound type of CDI unit cell would have a high performance deionization capability.