Developmental Trajectories of Attention in Normal Korean Population

Han Nah Huh,Sung Hee Kang,Soon Young Hwang,Hanik K. Yoo 대한소아청소년정신의학회 2019 소아청소년정신의학 Vol.30 No.2

Objectives: This study aimed to investigate the trajectory of change of diverse attention and working memory in Koreans from 4 to 40 years of age. Methods: The data of 912 subjects from 4 to 15 years of age obtained from a previous standardization study of the computerized comprehensive attention test were merged with the newly obtained data of 150 subjects aged 16 to 40 years from this study. We evaluated the various kinds of attention, in which each subtest had five indicators. Working memory, with parameters such as number of correct responses and span, was also measured. Results: Our findings indicated that attention developed as age increased, and it decreased or was maintained after a certain age. Selective and sustained attention developed rapidly in children and adolescents, until mid-teens or 20 s when it ceased development. Divided attention, however, developed up to approximately age 20. In addition, working memory developed until mid-teens or 20 s. Conclusion: We presented the standardized data on diverse kinds of attention and working memory in children, adolescents, and adults in Korea. We could recognize any patterns of change in attention and working memory with increasing age.

가황형태 및 온도가 천연고무 컴파운드의 물리적 특성에 미치는 영향

허양일,윤찬호,나창운,한승철,이종문 한국고무학회 2000 엘라스토머 및 콤포지트 Vol.35 No.3

Cure characteristics, tensile properties, and dynamic properties were investigated on the carbon black-filled natural rubber compounds, in which three typical vucanization types: conventional vulcanization(Conv), semi-efficient(Semi-EV), and efficient(EV) vulcanizations were used. The effects of vulcanization temperature on both the mechanical property and aging resistance of rubber compounds were also investigated. The Conv cure system showed a slightly slower rate of vulcanization than those of Semi-EV and EV ones. On the other hand, it showed a higher value in the maximum torque of cure curve. Higher tensile moduli were observed in Conv system than those in Semi-EV and EV ones, while lower elongation at break were obtained in Conv one. The tensile strength at break were found to be about the same for three cure systems. Hardness, modulus, and tensile strength decreased with increasing the vulcanization temperature, and the degree of changes in the properties was found to be smaller for EV and Semi-EV systems than that in Conv one. The EV system was found to be superior m thermal-aging resistance to Conv one.

Break - in Period 동안 시행한 혈액 투석이 지속성 외래 복막 투석 환자의 잔여 신기능에 미치는 영향

박진아(Ji Nah Park),김대중(Dae Joong Kim),정시정(Shi Jung Chung),한혁준(Hyeok Jun Han),허우성(Woo Seong Huh),김윤구(Yoon Goo Kim),오하영(Ha Young Oh) 대한신장학회 2001 Kidney Research and Clinical Practice Vol.20 No.1

복막 투석 도관 삽입 후, 도관 및 수술 부위에 관련된 합병증을 줄이기 위하여 도관 삽입 2주내지 4주 후 복막 투석을 시작하도록 권유하고 있고, 이 기간을 break -in period라고 한다. 일부 환자에서 이 기간 동안 유지 혈액 투석을 하게 되는 경우가 있다. 잔여 신기능이 혈액 투석을 하는 환자보다 복막 투석 환자에서 잘 보존되는 것으로 알려져 있으므로, 혈액 투석을 거치지 않고 복막 투석을 직접 시작한 환자에 비해 break-in period동안 혈액 투석을 한 환자에서 잔여 신기능이 더 감소할 것으로 예상된다. 이에 저자들은 지속성 외래 복막 투석 환자에서 break-in period동안에 시행한 혈액 투석이 잔여 신기능에 미치는 영향을 알아보기 위하여 이 연구를 시작하였다. 1999년 3월 이후 지속석 외래 복막 투석을 시작하고 임상적으로 안정적인 20명의 환자를 대상으로 하였다. 6명의 환자에서 1개월의 break-in period동안 혈액 투석을 시행하였고, 그 후 지속성 외래 복막 투석을 시작하였다(A군). 14명의 환자에서는 1개월, 3개월, 6개월 후에 사구체 여과율(소변에서 측정한 요소 청소율과 크레아티닌 청소율의 평균)과 소변에서의 요소 제거율(urine Kt/V)을 측정하였다. 잔여 신기능과의 상관관계를 보기 위한 변수로 평균 동맥혈압, 혈청 알부민, 혈색소, 적혈구 용적율, 연령, 성별, 당뇨병의 유무, 복막염의 발생을 관찰하였다. 신대체 요법 시작 시점에서 두 군의 평균 동맥혈압, 혈청 알부민, 혈색소, 적혈구 용적율, 연령, 성별 당뇨병의 유무는 통계학적인 차이는 없었다. 신대체 요법 시작 시점의 사구체 여과율은 A군이 B군보다 낮았으나(A군: 45.0±10.1L/week, B군: 54.6±5.7L/week), 통계학적인 차이는 없었다. 신대체 요법을 시작한 뒤 1개월 후 측정한 사구체 여과율은 B군에서는 변화가 별로 없었으나 A군에서는 현저히 감소하여 두 군 사이에 유의한 차이를 보였고(A군: 28.6±5.3L/week, B군: 54.4±5.7L/week), 이 차이는 6개월 시점까지 지속되었다. 사구체 여과율과 소변에서의 요소 제거율의 변화는 평균 동맥혈압, 혈청 알부민, 혈색소, 적혈구 용적율과 상관관계가 없었으며, 성별이나 당뇨병의 유무, 복막염의 빈도등에 의해 영향을 받지 않았다. Break-in periond의 혈액 투석은 잔여 신기능의 감소를 가져왔고 이는 신대체 요법후 6개월까지도 회복되지 않았다. 이에 저자들은 지속성 외래 복막 투석을 시행할 환자의 경우 적절한 시기에 도관을 삽입하여 혈액 투석에 의한 잔여 신기능의 감소를 피하는 것이 바람직할 것으로 생각하였다. To avoid later complication of peritoneal dialysis catheter, it is recommended to delay regular exchange of peritoneal dialysis for about 2-4weeks after insertion of catheter(break-in period). During break-in period some patients need hemodialysis(HD) or other intermittent dialysis. In such cases residual renal function(RRF) can decrease substantially compared with patients who do not need HD during break-in period since RRF is preserved better in CAPD patients than HD patients. This is prospective observational study to examine such an effect of HD during break-in period on residual renal function in CAPD patients. 20 patients who were clinically stable and had been on CAPD since March, 1999 were observed. 6 patients were treated with HD for 1month during break-in period and CAPD thereafter(group A). 14 patients were treated with CAPD without HD(group B). GFR(mean of creatinine and urea clearance of urine) and urine Kt/V urea were measured at start, and 1, 3, 6 months of renal replacement therapy. Covariables analyzed in this study were mean arterial blood pressure, serum albumin, hemoglobin, hematocrit, age, sex, the presence of diabetes mellitus, and peritonitis episode. There was no significant difference in initial RRF, mean arterial blood pressure, serum albumin, hemoglobin, hematocrit, age, sex, and the presence of diabetes mellitus between 2 groups. Initial GFR was a little smaller in group A than group B(45.0±10.1 L/week vs. 54.6±5.7L/week) which was not statistically significant. GFR after 1, 3 and 6months of dialysis(including 1month of HD in group A) were smaller in group A than B(28.6±5.3L/week vs. 54.4±5.7L/week, 32.7±5.2L/week vs 56.9±6.1Lweek, 21.0±4.1L/week vs 53.6±5.4L/week at 1,3,6 months after dialysis in group A and B), which were significant. Urine Kt/V showed same pattern. The change of GFR and urine Kt/V have no correlation with serum albumin, hemoglobin, hematocrit, and change of mean arterial blood pressure and is not affected by sex, and presence of DM or peritonitis. We concluded that HD during break-in period can decrease RRF in CAPD patients, which may not recover after 6months of dialysis. Avoiding HD during break-in period with appropriate preparation can preserve RRF in CAPD patients.

국내 제주지역 초등학생 읽기 및 수학 학습장해 유병률 연구

유한익(Hanik K. Yoo),허한나(Han-nah Huh),홍인화(In Hwa Hong),김중훈(Jung Hun Kim),김희정(Hee-Jung Kim),조성진(Seong-jin Cho),양수진(Su-Jin Yang),정재석(Jae-suk Jung) 대한신경정신의학회 2018 신경정신의학 Vol.57 No.4

Objectives This study investigated the prevalence of reading and mathematical learning disabilities of students at primary schools in Jeju Island, South Korea. We examined major causes of learning disabilities including reading disorder, mathematical disorder, attention deficit, and other causes including socioemotional factors. Methods We conducted screening processes to 659 participants (340 male, 51%) in 4 elementary schools in Jeju Island. To identify the causes of learning problems, 84 children were administered tests such as the Korean-Wechsler Intelligence Scale for Children-fourth edition, the Comprehensive Learning Test-Reading/Math, and the Comprehensive Attention Test. Results This study found that 13% of elementary school students in the Jeju region had learning disabilities. Among learning disabilities, specific reading and mathematical disorders accounted for 9% of study subjects. In addition, 2% of participants had intellectual impairment and 1% had other causes such as socioemotional factors. 65% of children with learning disabilities and 74% of children with reading or mathematic disorders had concurrent attention deficit disorder. 68% of children with reading disorders also had comorbid mathematical disorder. Conclusion The prevalence, causes, and comorbidity of reading and mathematical learning disabilities of students in Jeju Island, South Korea did not differ from those in foreign countries. Because most learning disabilities are complex, comprehensive evaluations and tailored interventions are necessary to help children with learning disabilities.