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Effect of Repetitive Transcranial Magnetic Stimulation in Drug Resistant Depressed Patients (치료 저항성 우울증 환자에서 반복적 경두개 자기자극후 국소뇌혈류 변화)

  • Chung, Yong-An;Yoo, Ie-Ryung;Kang, Bong-Joo;Chae, Jeong-Ho;Lee, Hye-Won;Moon, Hyun-Jin;Kim, Sung-Hoon;Sohn, Hyung-Sun;Chung, Soo-Kyo
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.1
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    • pp.9-15
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    • 2007
  • Purpose: Repetitive transcranial magnetic stimulation (rTMS) has recently been clinically applied in the treatment of drug resistant depressed patients. There are mixed findings about the efficacy of rTMS on depression. Furthermore, the influence of rTMS on the physiology of the brain is not clear. We prospectively evaluated changes of regional cerebral blood flow (rCBF) between pre- and post-rTMS treatment in patients with drug resistant depression. Materials and Methods: Twelve patients with drug-resistant depression (7 male, 5 female; age range: $19{\sim}52$ years; mean age: $29.3{\pm}9.3$ years) were given rTMS on right prefrontal lobe with low frequency (1 Hz) and on left prefrontal lobe with high frequency (20 Hz), with 20-minute-duration each day for 3 weeks. Tc-99m ECD brain perfusion SPECT was obtained before and after rTMS treatment. The changes of cerebral perfusion were analyzed using statistical parametric mapping (SPM; t=3.14, uncorrected p<0.01, voxel=100). Results: Following areas showed significant increase in rCBF after 3 weeks rTMS treatment: the cingulate gyrus, fusiform gyrus of right temporal lobe, precuneus, and left lateral globus pallidus. Significant decrement was noted in: the precental and middle frontal gyrus of right frontal lobe, and fusiform gyrus of left occipital lobe. Conclusion: Low-frequency rTMS on the right prefrontal cortex and high-frequency rTMS on the left prefrontal cortex for 3 weeks as an add-on regimen have increased and decreased rCBF in the specific brain regions in drug-resistant depressed patients. Further analyses correlating clinical characteristics and treatment paradigm with functional imaging data may be helpful in clarifying the pathophysiology of drug-resistant depressed patients.

Taxonomical Classification and Genesis of Jeju Series in Jeju Island (제주도 토양인 제주통의 분류 및 생성)

  • Song, Kwan-Cheol;Hyun, Byung-Geun;Moon, Kyung-Hwan;Jeon, Seung-Jong;Lim, Han-Cheol;Lee, Shin-Chan
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.2
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    • pp.230-236
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    • 2010
  • Jeju Island is a volanic island which is located about 96 km south of Korean Peninsula. Volcanic ejecta, and volcaniclastic materials are widespread as soil parent materials throughout the island. Soils on the island have the characteristics of typical volcanic ash soils. This study was conducted to reclassify Jeju series based on the second edition of Soil Taxonomy and to discuss the formation of Jeju series in Jeju Island. Morphological properties of typifying pedon of Jeju series were investigated, and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon has dark brown (10YR 3/3) silt clay loam A horizon (0~22 cm), strong brown (7.5YR 4/6) silty clay BAt horizon (22~43 cm), brown (7.5YR 4/4) silty clay Bt1 horizon (43~80 cm), brown (7.5YR 4/6) silty clay loamBt2 horizon (80~105 cm), and brown (10YR 5/4) silty clay loam Bt3 horizon (105~150 cm). It is developed in elevated lava plain, and are derived from basalt, and pyroclastic materials. The typifying pedon contains 1.3~2.1% oxalate extractable (Al + 1/2 Fe), less than 85%phosphate retention, and higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to 150 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol. Its has 0.9% or more organic carbon in the upper 15 cm of the argillic horizon, and can be classified as Humult. It dose not have fragipan, kandic horizon, sombric horizon, plinthite, etc. in the given depths, and key out as Haplohumult. A hoizon (0~22 cm) has a fine-earth fraction with both a bulk density of 1.0 Mg $cm^{-3}$ or less, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0. Thus, it keys out as Andic Haplohumult. It has 35% or more clay at the particle-size control section, and has thermic soil temperature regime. Jeju series can be classified as fine, mixed, themic family of Andic Haplohumults, not as ashy, thermic family of Typic Hapludands. In the western, and northern coastal areas which have a relatively dry climate in Jeju Island, non Andisols are widely distributed. Mean annual precipitation increase 110 mm, and mean annual temperature decrease $0.8^{\circ}C$ with increasing elevation of 100m. In the western, and northern mid-mountaineous areas Andisols, and non Andisols are distributed simultaneously. Jeju series distributed mainly in the western and northern mid-mountaineous areas are developed as Ultisols with Andic subgroup.

The Hardness Water Production By RO/NF/ED Linking Process From Deep Seawater (RO/NF/ED 연계 공정에 의한 고경도 담수 제조)

  • Moon, Deok-Soo;Kim, Kwang Soo;Gi, Ho;Choi, Mi Yeon;Jung, Hyun Ji;Kim, Hyun Ju
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.16 no.4
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    • pp.227-238
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    • 2013
  • The purpose of this study is to develop a process technology to produce high hardness drinking water which meet drinking water standard, remaining useful minerals like magnesium and calcium in the seawater desalination process while removing the sulfate ions and chloride ions. Seawater have been separated the concentrated seawater and desalted seawater by passing on Reverse Osmosis membrane (RO). Using Nano-filtration membrane (NF), We were prepared primary mineral concentrated water that sodium chloride were not removed. By the operation of electro-dialysis (ED) having ion exchange membrane, we were prepared concentrated mineral water (Mineral enriched desalted water) which the sodium chloride is removed. We have produced the high hardness water to meet the drinking water quality standards by diluting the mineral enriched desalted water with deionized water by RO. Reverse osmosis membranes (RO) can separate dissolved material and freshwater from seawater (deep seawater). The desalination water throughout the second reverse osmosis membrane was completely removed dissolved substances, which dissolved components was removed more than 99.9%, its the hardness concentration was 1 mg/L or less and its chloride concentration was 2.3 mg/L. Since the nano-filtration membrane pore size is $10^{-9}$ m, 50% of magnesium ions and calcium ions can not pass through the nano-filtration membrane, while more than 95% of sodium ions and chloride ions can pass through NF membrane. Nano-filtration membrane could be separated salt components like sodium ion and chloride ions and hardness ingredients like magnesium ions and calcium ions, but their separation was not perfect. Electric dialysis membrane system can be separated single charged ions (like sodium and chloride ions) and double charged ions (like magnesium and calcium ions) depending on its electrical conductivity. Above electrical conductivity 20mS/cm, hardness components (like magnesium and calcium ions) did not removed, on the other hand salt ingredients like sodium and chloride ions was removed continuously. Thus, we were able to concentrate hardness components (like magnesium and calcium ions) using nano-filtration membrane, also could be separated salts ingredients from the hardness concentration water using electrical dialysis membrane system. Finally, we were able to produce a highly concentrated mineral water removed chloride ions, which hardness concentration was 12,600 mg/L and chloride concentration was 2,446 mg/L. By diluting 10 times these high mineral water with secondary RO (Reverse Osmosis) desalination water, we could produce high mineral water suitable for drinking water standards, which chloride concentration was 244 mg/L at the same time hardness concentration 1,260 mg/L. Using the linked process with reverse osmosis (RO)/nano filteration (NF)/electric dialysis (ED), it could be concentrated hardness components like magnesium ions and calcium ions while at the same time removing salt ingredients like chloride ions and sodium ion without heating seawater. Thus, using only membrane as RO, NF and ED without heating seawater, it was possible to produce drinking water containing high hardness suitable for drinking water standard while reducing the energy required to evaporation.

The evaluation of the feasibility about prostate SBRT by analyzing interfraction errors of internal organs (분할치료간(Interfraction) 내부 장기 움직임 오류 분석을 통한 전립선암의 전신정위적방사선치료(SBRT) 가능성 평가)

  • Hong, soon gi;Son, sang joon;Moon, joon gi;Kim, bo kyum;Lee, je hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.28 no.2
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    • pp.179-186
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    • 2016
  • Purpose : To figure out if the treatment plan for rectum, bladder and prostate that have a lot of interfraction errors satisfies dosimetric limits without adaptive plan by analyzing MR image. Materials and Methods : This study was based on 5 prostate cancer patients who had IMRT(total dose: 70Gy) Using ViewRay MRIdian System(ViewRay, ViewRay Inc., Cleveland, OH, USA) The treatment plans were made on the same CT images to compare with the plan quality according to adaptive plan, and the Eclipse(Ver 10.0.42, Varian, USA) was used. After registrate the 5 treatment MR images to the CT images for treatment plan to analyze the interfraction changes of organ, we measured the dose volume histogram and the changes of the absolute volume for each organ by appling the first treatment plan to each image. Over 5 fractions, the total dose for PTV was $V_{36.25}$ Gy $${\geq_-}$$ 95%. To confirm that the prescription dose satisfies the SBRT dose limit for prostate, we measured $V_{100%}$, $V_{95%}$, $V_{90%}$ for CTV and $V_{100%}$, $V_{90%}$, $V_{80%}$ $V_{50%}$ of rectum and bladder. Results : All dose average value of CTV, rectum and bladder satisfied dose limit, but there was a case that exceeded dose limit more than one after analyzing the each image of treatment. After measuring the changes of absolute volume comparing the MR image of the first treatment plan with the one of the interfraction treatment, the difference values were maximum 1.72 times at rectum and maximum 2.0 times at bladder. In case of rectum, the expected values were planned under the dose limit, on average, $V_{100%}=0.32%$, $V_{90%}=3.33%$, $V_{80%}=7.71%$, $V_{50%}=23.55%$ in the first treatment plan. In case of rectum, the average of absolute volume in first plan was 117.9 cc. However, the average of really treated volume was 79.2 cc. In case of CTV, the 100% prescription dose area didn't satisfy even though the margin for PTV was 5 mm because of the variation of rectal and bladder volume. Conclusion : There was no case that the value from average of five fractions is over the dosimetric limits. However, dosimetric errors of rectum and bladder in each fraction was significant. Therefore, the precise delivery is needed in case of prostate SBRT. The real-time tracking and adaptive plan is necessary to meet the precision delivery.

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Clinical Results after Repair of Rotator Cuff Tear in Patients with Accompanying AC Joint Pathology: Clinical Comparison of Non-operative Treatment (회전근개 파열과 동반된 견봉 쇄골 관절 병변이 회전근개 봉합술 후 결과에 미치는 영향: 비수술적 치료를 통한 임상적 비교)

  • Yoo, Moon-Jib;Seo, Joong-Bae;Lee, Dae-Hee;Kim, Sung-Jin
    • Clinics in Shoulder and Elbow
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    • v.15 no.2
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    • pp.86-90
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    • 2012
  • Purpose: We studied the need for distal clavicle resection by comparing rotator cuff tear patients who underwent non-surgical treatment with and without acromioclavicular joint pathology. Materials and Methods: 45 cases that had been under follow up care for at least 9 months after receiving rotator cuff repair in our hospital between Jan. 2005 and Jun. 2011 had been studied. Acromioclavicular joint pathology group and control group were classified by physical examination and MRI findings. The temporal changes in shoulder joint abduction, internal and external rotation strength, ASES and KSS score of the two groups were measured and analyzed. Results: The acromioclavicular joint pathology complicated rotator cuff injury group's strength measurements for abduction, internal rotation, external rotation were each 8.05 (${\pm}4.54$), 11.33 (${\pm}6.05$), 10.24 (${\pm}5.27$) preoperatively and improved to 13.26 (${\pm}5.50$), 17.51 (${\pm}6.80$), 15.60 (${\pm}5.37$) post operatively while the KSS score and ASES score were each 49.07 (${\pm}15.28$) and 48.65 (${\pm}13.27$) preoperatively, improving to 84.48 (${\pm}10.96$) and 84.65. (${\pm}9.86$). The measurements for the group without complicating acromioclavicular pathology are as follows. The strength for abduction, internal rotation, external rotation was each 6.42 (${\pm}3.11$), 7.59 (${\pm}4.81$) and 7.93 (${\pm}4.49$) preoperatively, improving to 15.85 (${\pm}7.35$), 19.18 (${\pm}9.14$), 16.95 (${\pm}5.70$) post operatively, while the KSS score and ASES score each went from 42.12 (${\pm}6.43$) and 41.37 (${\pm}7.42$) to 83.44 (${\pm}6.30$) and 83.17 (${\pm}7.01$) respectively. The measurements for the two groups, however, did not show a statistically significant difference (p>0.05). Conclusion: Analysis of the rotator cuff injury groups with and without AC joint pathology showed that both groups had improved strength, ASES and KSS scores with no statistical difference difference among the groups. As such, it thought that conservative treatment is an acceptable alternative to distal clavicle resection.

Hepatitis Complicated with Mycoplasma pneumoniae Infection in Children (소아의 Mycoplasma pneumoniae 폐렴에 합병된 간염)

  • Lee, Seung Min;Lee, Sung Moon;Tchah, Hann;Jeon, In Sang;Ryoo, Eell;Cho, Kang Ho;Seon, Yong Han;Son, Dong Woo;Hong, Hee Joo
    • Clinical and Experimental Pediatrics
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    • v.48 no.8
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    • pp.832-838
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    • 2005
  • Purpose : Mycoplasma pneumoniae infection is relatively common in childhood. Its extrapulmonary manifestations have been reported so much, but hepatitis associated with it has been reported rarely in Korea. Methods : A clinical study was performed on 556 patients of M. pneumoniae pneumonia diagnosed serologically at Gil hospital from January 2001 to December 2004. We reviewed 65 cases among these patients, who had elevated level of serum AST and ALT greater than 50 IU/L respectively without evidence of hepatitis A, B, C, Cytomegalovirus and Ebstein-Barr virus infections. Results : Hepatitis occurred in 11.7% of Mycoplasma pneumoniae pneumonia, especially in fall and winter times. Male to female ratio was 1.2 : 1 and the mean age was 4 years and 3 months. Besides hepatitis, cough(95.4%), sputum(52.3%) and dyspnea(12.3%) were common as pulmonary manifestations. And among gastrointestinal manifestations, nausea/vomiting(26.2%) was the most common symptom, followed by poor oral intake(12.3%), diarrhea(12.3%) and abdominal pain(6.2%). In addition to hepatomegaly(4.6%) and splenomegaly(4.6%), coarse breathing sound was the most common physical manifestation, followed by rale(63.1%), pharyngeal injection(26.2%), and rash(10.8%). Anemia was noted in 20.0%, neutrophilia in 10.8%, eosinphilia in 38.5% and thrombocytosis in 6.2%, respectively. Mean level of ESR and CRP was 32.02 mm/hr and 6.69 mg/dL, respectively. Mean level of AST and ALT was 293.80 IU/L and 181.48 IU/L, respectively. Hyperbilirubinemia was noted in 7.7% and hypoalbuminemia was noted in 58.5%. Lobar or lobular pneumonia(78.5%) was the most common finding in chest X-ray and left lower lobe(39.2%) was most commonly affected. Pleural effusion was noted in 26.2%. Mean duration of hospitalization was 9.91 days. Serum AST/ALT level was normalized within 9.94 days and pulmonary consolidation resolved within 14.29 days. Conclusion : The prognosis of M. pneumoniae hepatitis is good. However, liver function should be considerately checked in M. pneumoniae infection because its incidence is not so low.

Macromineral intake in non-alcoholic beverages for children and adolescents: Using the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV, 2007-2009) (어린이와 청소년의 비알콜성음료 섭취에 따른 다량무기질 섭취량 평가: 제 4기 국민건강영양조사 자료를 활용하여)

  • Kim, Sung Dan;Moon, Hyun-Kyung;Park, Ju Sung;Lee, Yong Chul;Shin, Gi Young;Jo, Han Bin;Kim, Bog Soon;Kim, Jung Hun;Chae, Young Zoo
    • Journal of Nutrition and Health
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    • v.46 no.1
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    • pp.50-60
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    • 2013
  • The aims of this study were to estimate daily intake of macrominerals from beverages, liquid teas, and liquid coffees and to evaluate their potential health risks for Korean children and adolescents (1-to 19 years old). Assessment of dietary intake was conducted using the actual level of sodium, calcium, phosphorus, potassium, and magnesium in non-alcoholic beverages and (207 beverages, 19 liquid teas, and 24 liquid coffees) the food consumption amount drawn from "The Fourth Korea National Health and Nutrition Examination Survey (2007-2009)". To estimate the dietary intake of non-alcoholic beverages, 6,082 children and adolescents (Scenario I) were compared with 1,704 non-alcoholic beverage consumption subjects among them (Scenario II). Calculation of the estimated daily intake of macrominerals was based on point estimates and probabilistic estimates. The values of probabilistic macromineral intake, which is a Monte-Carlo approach considering probabilistic density functions of variables, were presented using the probabilistic model. The level of safety for macrominerals was evaluated by comparison with population nutrient intake goal (Goal, 2.0 g/day) for sodium, tolerable upper intake level (UL) for calcium (2,500 mg/day) and phosphorus (3,000-3,500 mg/day) set by the Korean Nutrition Society (Dietary Reference Intakes for Koreans, KDRI). For total children and adolescents (Scenario I), mean daily intake of sodium, calcium, phosphorus, potassium, and magnesium estimated by probabilistic estimates using Monte Carlo simulation was, respectively, 7.93, 10.92, 6.73, 23.41, and 1.11, and 95th percentile daily intake of those was, respectively, 28.02, 44.86, 27.43, 98.14, and 3.87 mg/day. For consumers-only (Scenario II), mean daily intake of sodium, calcium, phosphorus, potassium, and magnesium estimated by probabilistic estimates using Monte Carlo simulation was, respectively, 19.10, 25.77, 15.83, 56.56, and 2.86 mg/day, and 95th percentile daily intake of those was, respectively, 62.67, 101.95, 62.09, 227.92, and 8.67 mg/day. For Scenarios I II, sodium, calcium, and phosphorus did not have a mean an 95th percentile intake that met or exceeded the 5% of Goal and UL.

Increased Peripheral NK Cell Fraction and Their Cytolytic activity in Patients with History of Recurrent Spontaneous Abortion (말초혈액 자연살해세포 분획 및 세포용해 활성도 분석을 통한 습관성 유산 위험군의 진단적 유용성에 관한 연구)

  • Choi, Ji-Young;Hwang, Su-Jin;Han, Ae-Ra;Yoo, Ji-Hee;Park, Dong-Wook;Park, Chan-Woo;Kim, Hye-Ok;Cha, Sun-Hwa;Kim, Jin-Young;Song, In-Ok;Koong, Mi-Kyoung;Kang, In-Soo;Yang, Kwang-Moon
    • Clinical and Experimental Reproductive Medicine
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    • v.37 no.2
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    • pp.115-124
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    • 2010
  • Objective: To testify whether the increased peripheral blood natural killer (pbNK) cells fraction and their cytolytic activity could coincide with patient's history of recurrent spontaneous abortion (RSA) and to evaluate these factors are can be valuable diagnostic markers in RSA. Methods: Women with a history of RSA comprised the patient group (n=35). Normal fertile women, who were experienced at least one healthy term birth without history of infertility or recurrent miscarriage, were included as the healthy control group (n=15). The pbNK cells of $CD3^-/CD56^+/CD16^+$ and their cytolytic activities against K562 cells were measured by flow cytometry and the values were compared between study and control groups. Results: Proportions of pbNK cells among peripheral blood monocytes (PBMC) ($14.2{\pm}5.2$ vs. $9.4{\pm}3.7%$, p=0.002, 95% confidence interval [CI], 1.8 to 7.8) was significantly higher in the patient group. The odds ratio of having RSA history was increased as 8.4 folds (59% of sensitivity, 80% of specificity, and 95% CI: 2.0 to 35.8) in patients who showed pbNK cells fraction above 12.1% which was determined as cut-off value by using ROC curve analysis. The cytolytic activities of pbNK cells which measured by three different ratio of effecter pbNK cells to target K562 cells and calculated by the percent of cytolytic K562 cells, were significantly higher in study group than that of control group (in 50:1 ratio, $48.3{\pm}19.0$ vs. $31.3{\pm}11.9%$, p=0.002; in 25:1 ratio, $37.0{\pm}18.1$ vs. $20.2{\pm}9.2%$, p<0.001; in 12.5:1 ratio, $23.5{\pm}12.7$ vs. $12.4{\pm}7.3%$, p=0.001). With the cut-off values of cytolytic activity of pbNK cells as 43.1% (50:1), 26.9% (25:1), and 17.4% (12.5:1) each, the risk of having RSA history was increased by 10.0, 11.4, and 15.0 folds in patients who had increased in each effector of pbNK to target of K562 cells ratio. Conclusion: The analysis of pbNK cells fraction and their cytolytic activity can be valuable diagnostic markers for RSA. We are going to planning the large scaled studies which include the data of obstetric outcomes in subsequent pregnancies to clarify our results of this study.

Current feeding practices and maternal nutritional knowledge on complementary feeding in Korea (이유기 보충식 현황과 어머니 인식 조사)

  • Yom, Hye Won;Seo, Jeong Wan;Park, Hyesook;Choi, Kwang Hae;Chang, Ju Young;Ryoo, Eell;Yang, Hye Ran;Kim, Jae Young;Seo, Ji Hyun;Kim, Yong Joo;Moon, Kyung Rye;Kang, Ki Soo;Park, Kie Young;Lee, Seong Soo;Shim, Jeong Ok
    • Clinical and Experimental Pediatrics
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    • v.52 no.10
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    • pp.1090-1102
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    • 2009
  • Purpose:To evaluate current feeding practices and maternal nutritional knowledge on complementary feeding. Methods:Mothers of babies aged 9-15 months who visited pediatric clinics of 14 general hospitals between September and December 2008 were asked to fill questionnaires. Data from 1,078 questionnaires were analyzed. Results:Complementary food was introduced at 4-7 months in 89% of babies. Home-made rice gruel was the first complementary food in 93% cases. Spoons were used for initial feeding in 97% cases. At 6-7 months, <50% of babies were fed meat (beef, 43%). Less than 12-month-old babies were fed salty foods such as salted laver (35%) or bean-paste soup (51%) and cow's milk (11%). The following were the maternal sources of information on complementary feeding: books/magazines (58%), friends (30%), internet web sites (29%), relatives (14%), and hospitals (4%). Compared to the 1993 survey, the incidence of complementary food introduction before 4 months (0.4% vs. 21%) and initial use of commercial food (7% vs. 39%) had decreased. Moreover, spoons were increasingly used for initial feeding (97% vs. 57%). The average maternal nutritional knowledge score was 7.5/10. Less percentage of mothers agreed with the following suggestions: bottle formula weaning before 15-18 months (68%), no commercial baby drinks as complementary food (67%), considering formula (or cow's milk) better than soy milk (65%), and feeding minced meat from 6-7 months (57%). Conclusion:Complementary feeding practices have considerably improved since the last decade. Pediatricians should advise timely introduction of appropriate complementary foods and monitor diverse information sources on complementary feeding.

Electronic Roll Book using Electronic Bracelet.Child Safe-Guarding Device System (전자 팔찌를 이용한 전자 출석부.어린이 보호 장치 시스템)

  • Moon, Seung-Jin;Kim, Tae-Nam;Kim, Pan-Su
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.143-155
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    • 2011
  • Lately electronic tagging policy for the sexual offenders was introduced in order to reduce and prevent sexual offences. However, most sexual offences against children happening these days are committed by the tagged offenders whose identities have been released. So, for the crime prevention, we need measures with which we could minimize the suffers more promptly and actively. This paper suggests a new system to relieve the sexual abuse related anxiety of the children and solve the problems that electronic bracelet has. Existing bracelets are only worn by serious criminals, and it's only for risk management and positioning, there is no way to protect the children who are the potential victims of sexual abuse and there actually happened some cases. So we suggest also letting the students(children) wear the LBS(Location Based Service) and USN(Ubiquitous Sensor Network) technology based electronic bracelets to monitor and figure out dangerous situations intelligently, so that we could prevent sexual offences against children beforehand, and while a crime is happening, we could judge the situation of the crime intelligently and take swift action to minimize the suffer. And by checking students' attendance and position, guardians could know where their children are in real time and could protect the children from not only sexual offences but also violent crimes against children like kidnapping. The overall system is like follows : RFID Tag for children monitors the approach of offenders. While an offender's RFID tag is approaching, it will transmit the situation and position as the first warning message to the control center and the guardians. When the offender is going far away, it turns to monitoring mode, and if the tag of the child or the offender is taken off or the child and offender stay at one position for 3~5 minutes or longer, then it will consider this as a dangerous situation, then transmit the emergency situations and position as the second warning message to the control center and the guardians, and ask for the dispatch of police to prevent the crime at the initial stage. The RFID module of criminals' electronic bracelets is RFID TAG, and the RFID module for the children is RFID receiver(reader), so wherever the offenders are, if an offender is at a place within 20m from a child, RFID module for children will transmit the situation every certain periods to the control center by the automatic response of the receiver. As for the positioning module, outdoors GPS or mobile communications module(CELL module)is used and UWB, WI-FI based module is used indoors. The sensor is set under the purpose of making it possible to measure the position coordinates even indoors, so that one could send his real time situation and position to the server of central control center. By using the RFID electronic roll book system of educational institutions and safety system installed at home, children's position and situation can be checked. When the child leaves for school, attendance can be checked through the electronic roll book, and when school is over the information is sent to the guardians. And using RFID access control turnstiles installed at the apartment or entrance of the house, the arrival of the children could be checked and the information is transmitted to the guardians. If the student is absent or didn't arrive at home, the information of the child is sent to the central control center from the electronic roll book or access control turnstiles, and look for the position of the child's electronic bracelet using GPS or mobile communications module, then send the information to the guardians and teacher so that they could report to the police immediately if necessary. Central management and control system is built under the purpose of monitoring dangerous situations and guardians' checking. It saves the warning and pattern data to figure out the areas with dangerous situation, and could help introduce crime prevention systems like CCTV with the highest priority. And by DB establishment personal data could be saved, the frequency of first and second warnings made, the terminal ID of the specific child and offender, warning made position, situation (like approaching, taken off of the electronic bracelet, same position for a certain time) and so on could be recorded, and the data is going to be used for preventing crimes. Even though we've already introduced electronic tagging to prevent recurrence of child sexual offences, but the crimes continuously occur. So I suggest this system to prevent crimes beforehand concerning the children's safety. If we make electronic bracelets easy to use and carry, and set the price reasonably so that many children can use, then lots of criminals could be prevented and we can protect the children easily. By preventing criminals before happening, it is going to be a helpful system for our safe life.