農民技術受容에 影響을 주는 要因의 比較分析 : 關係機關과 情報傳達媒體를 中心으로

鄭址雄,崔敏浩,金性洙,徐圭善,李昶植 서울大學校 農科大學 1984 서울대농학연구지 Vol.9 No.2

The purpose of the study was to analyze the variables affecting farmers' adoption process of agricultural innovations in Korea. Specific objectives of the study were to ; (1) review the adoption process and the variables associated with this process, (2) investigate the rate of adoption of selected agricultural innovations in the fields of rice production, animal husbandary and horticulture, (3) analyze communication media and change agencies or institutions which affected the adoption of agricultural innovations, and (4) identify the relations of the farmers' adoption and communication exposure behavior. Data for the study were collected from 393 cluster sampled farmers out of selected 17 rural villages in Korea. Five graduate students and three faculty members of Seoul National University participated in conducting interview with pre-tested questionnairs. The data were analyzed by HP 3,000 computer in the College of Agriculture, Seoul National University. Major statistical techniques used for the study were frequency distribution, chi-square and discriminant analysis. Statistical significance was tested at .05 level. The major findings of the study were as follows : 1. Variables associated with the agricultural adoption process were classified into the following six categories ; (1) perceived characteristics of agricultural innovations, (2) personality and characteristics of adopters, (3) the patterns of communication media or channels, (4) efforts of change agents. (5) priorities in agricultural development policies, and (6) characteristics of social system. 2. Rats of adoption were about 83% in application of silicate fertilizers on rice seed bed, 41% in feeding calf starter known as artificial milk to calves, 56% vinyl mulching practices in vegetable cultivation, and 67% in spreading raw rice straw on paddy land to improve soil conditions. 3. Time lag between awareness and adoption appeared to be about seven months in application of silicate fertilizers on rice seed bed, and about a year in feeding calf starter. 4. Change agent interpersonal communication revealed to be the most important factor affecting farmers' awareness in application of silicate fertilizers on rice seed bed, in feeding calf starter, and in spreading raw rice straw on paddy land, while localite interpersonal communication in vinyl mulching practices in vegetable cultivation. 5. Change agent interpersonal communication appeared to be the most important factor affecting farmers' adoption in application of silicate fertilizers on rice seed bed and in feeding calf-starter, Localite interpersonal communications were more important in vinyl mulching practices of vegetable cultivation and in spreading raw rice straw. Localite interpersonal communications were more important factor at adoption stage than at awarenss stage. 6. Agricultural extension agencies appeared to be the most important factor affecting farmers' adoption in application of silicate fertilizers on rice seed bed, in feeding calf starter, and in vinyl mulching practices. Based on the results of this study, the following are recommended for further development of agricultural extension services and effective adoption process of agricultural innovation. 1. The variables associated with the agricultural innovation decision process should be taken into consideration to improve effectiveness of change agencies or agricultural extension services. 2. Effective use of communication media along with the feedback messages from the change agency as well as client system be considered to increase effectiveness and meaningfulness of both systems. 3. Innovative agricultural research be continually sharpen its focus on the highest priority needs of client system by utilizing feedback from farmers through the communication link of change agents. 4. A long-term educational approach by using various communication media be emphasized, and regular field survey on innovation-decision process will prevent discontinuance of innovations.

900 MHz 대역 CMOS 가변이득 증폭기 설계

이지호,채규성,윤상웅,김창우 慶熙大學校 레이저 工學硏究所 2007 레이저공학 Vol.18 No.-

A vairable gain amplifier(VGA) has been designed for 900 MHz-band applications. The VGA consist of three blocks; a control voltage feeding block, variable gain block, and constant gain block. The VGA has been simulated using the TSMC CMOS libraries. At 900 MHz, the maximum gain is 34.6 dB with an 1 - dB gain compression output power of 3 dBm. The gain control range is 30 dB from 3.8 dB to 34.6 dB by the control voltage from 0.9 to 3.0 V. The gain control sensitivity of the VGA is 70 mV/dB, which is larger than a thermal voltage (26 mV/dB at the room temperature) in order to be insensitive to temperature variation.

전이성 신세포암 환자에서의 IFN-α와 5-FU를 이용한 복합 면역 화학 요법

김세웅,이지열,장광식,박왕진,정호석,조용현,윤문수 대한화학요법학회 2000 대한화학요법학회지 Vol.18 No.3

목적 : 전이성 신세포암의 경우 일반적으로 항암 화학요법, 방사선 치료 그리고 호르몬 치료 등의 다양한 치료 방법에도 불구하고 그 치료 성적이 불량하며 최근 진행된 전이성 신세포암이 치료에 사용되고 있는 면역요법과 면역화학요법의 치료 효과에 대한 많은 논란이 있다. 이에 저자들은 전이성 신세포암 환자들을 대상으로 시행한 interferon-α와 5-fluorouracil의 병용투여에 대한 면역화학요법의 치료 성적, 추적관찰 결과 및 부작용의 발현정도를 확인하여 그 임상적 유용성을 알아보고자 하였다. 방법 : 1995년 3월부터 2000년 2월까지 가톨릭 대학 부속 성모 병원에서 치료를 받았던 진행성, 전이성 신세포암 환자들 중 interferon-α와 5-fluorourcail의 복합면역화학요법을 시행 받고 추적관찰이 가능했던 총 17명의 환자를 대상으로 하였다. 대상 환자들에 대해 28일을 주기로 5-fluorouracil 750㎎/㎡(Body surface area)을 5일간 지속성 정맥 주사로 투여한 후 주 3회 interferon-α 300만 unit를 4주간 피하 주사하였다. 이들에 대해 8주마다 전산화 단층촬영, 동위원소 골주사, 흉부단순 촬영 등의 영상 진단을 통한 정기적인 추적 관찰을 시행하고 이들의 치료 성적, 추적관찰 결과 및 부작용 등에 대해 알아보았다. 결과 : Interferon-α와 5-Fluorouracil의 복합면역화학요법을 이용한 전체 17명의 전이성 신세포 암 환자의 경우 반응율은 완전관해는 없었으나 부분관해를 보인 경우가 2명(11.8%), 안정상태 유지는 6명(35.3%)이었다. 폐전이의 경우 복합면역화학요법에 대해 비교적 좋은 반응을 기대할 수 있었으며 이들의 생존 기간의 중앙값은 13.8개월이었다. 거의 모든 환자에서 미열을 동반한 전신 증상과 전신 쇠약감을 관찰 할 수 있었고 그 밖에 오심, 구토 및 설사 등의 소화기 증상과 두통 등의 경미한 부작용을 일부 환자에서 관찰할 수 있었으나 백혈구 감소증, 혈소판 감소증과 간기능 이상 등의 심각한 부작용을 보인 경우는 극히 적었다. 결론 : 전이성 신세포암은 비교적 그 예후가 불량하며 동시에 효과적인 치료 방법이 명확히 알려지지 않은 상태이다. 이러한 전이성 신세포암의 치료에 대한 interferon-α와 5-fluorouracil의 복합면역화학요법은 다른 종양의 치료에 비해 비교적 낮은 반응률과 고비용이 문제점으로 생각되나 비교적 부작용이 적은 안전한 치료 방법이므로 전이상 신세포암 환자에 있어 시행해 볼 가치가 있는 치료 방법의 하나로 사료된다. Background : Renal cell carcinoma is relatively resistant to both chemotherapy and immunotherapy. In this study, we evaluated and verified the efficacy and toxicity of therapies using interferon-α plus 5-fluorouracil in patients with metastatic renal cell carcinoma. Methods : A total of 17 patients with metastatic renal cell carcinoma were treated with interferon-α (3 million units/day. 3 times/week) subcutaneously plus 5-fluorouracil (750㎎/㎡ /day for 5 days) intravenously every 28 days from March 1995 to February 2000. We studied the response rate and the side effects of this regimen. Results : Among 17 patients treated with interferon-a plus 5-fluorouracil, 2 patient with lung metastasis was achieved partial remission (11.8%) and 3 patient with lymph node metastasis, 2 patients with lung metastasis and I patient with lung and bone metastases were achieved stable disease (35.3%). I and 5 year survival rates and median survival duration were 55%, 7% and 13.8 months, respectively. There were only mild to moderate side effects. The most common side effects were flu-like symptom such as fever, chill and malaise followed by gastrointestinal symptom such as nausea, vomiting and diarrhea, headache. High grade toxicities such as severe neutropenia and thrombocytopenia were rare. Conclusion : Immunochemotherapy using interferon-α plus 5-fluorouracil were moderately effective with modest toxicity in metastatic renal cell carcinoma. The most favorable response can be expected in lung metastasis. Most of side effects were tolerable. The effective therapy in patients with metastatic renal cell carcinoma should be studied and evaluated by further large randomized trials.

Hypopituitarism after Gamma Knife surgery for postoperative nonfunctioning pituitary adenoma

Oh, Ji Woong,Sung, Kyoung Su,Moon, Ju Hyung,Kim, Eui Hyun,Chang, Won Seok,Jung, Hyun Ho,Chang, Jin Woo,Park, Yong Gou,Kim, Sun Ho,Chang, Jong Hee American Association of Neurological Surgeons 2018 Journal of Neurosurgery Vol.129 No.suppl1

<B>OBJECTIVE</B><P>This study investigated long-term follow-up data on the combined pituitary function test (CPFT) in patients who had undergone transsphenoidal surgery (TSS) for nonfunctioning pituitary adenoma (NFPA) to determine the clinical parameters indicative of hypopituitarism following postoperative Gamma Knife surgery (GKS).</P><B>METHODS</B><P>Between 2001 and 2015, a total of 971 NFPA patients underwent TSS, and 76 of them (7.8%) underwent postoperative GKS. All 76 patients were evaluated with a CPFT before and after GKS. The hormonal states were analyzed based on the following parameters: relevant factors before GKS (age, sex, extent of resection, pre-GKS hormonal states, time interval between TSS and GKS), GKS-related factors (tumor volume; radiation dose to tumor, pituitary stalk, and normal gland; distance between tumor and stalk), and clinical outcomes (tumor control rate, changes in hormonal states, need for hormone-related medication due to hormonal changes).</P><B>RESULTS</B><P>Of the 971 NFPA patients, 797 had gross-total resection (GTR) and 174 had subtotal resection (STR). Twenty-five GTR patients (3.1%) and 51 STR patients (29.3%) underwent GKS. The average follow-up period after GKS was 53.5 ± 35.5 months, and the tumor control rate was 96%. Of the 76 patients who underwent GKS, 23 were excluded due to pre-GKS panhypopituitarism (22) or loss to follow-up (1). Hypopituitarism developed in 13 (24.5%) of the remaining 53 patients after GKS. A higher incidence of post-GKS hypopituitarism occurred in the patients with normal pre-GKS hormonal states (41.7%, 10/24) than in the patients with abnormal pre-GKS hormonal states (10.3%, 3/29; p = 0.024). Target tumor volume (4.7 ± 3.9 cm<SUP>3</SUP>), distance between tumor and pituitary stalk (2.0 ± 2.2 mm), stalk dose (cutoffs: mean dose 7.56 Gy, maximal dose 12.3 Gy), and normal gland dose (cutoffs: maximal dose 13.9 Gy, minimal dose 5.25 Gy) were factors predictive of post-GKS hypopituitarism (p < 0.05).</P><B>CONCLUSIONS</B><P>This study analyzed the long-term follow-up CPFT data on hormonal changes in NFPA patients who underwent GKS after TSS. The authors propose a cutoff value for the radiation dose to the pituitary stalk and normal gland for the prevention of post-GKS hypopituitarism.</P>

Prevalence and Progression of Stage 0 Macular Hole in Fellow Eyes of Patients with Idiopathic Full-thickness Macular Hole

Ji Woong Chun,Chang Hwan Kim,Ju Young Kim,Hyun Sub Oh,Soon Hyun Kim,Oh Woong Kwon,Yong Sung You 대한안과학회 2021 Korean Journal of Ophthalmology Vol.35 No.2

Purpose: To assess the prevalence and progression of a stage 0 macular hole in the fellow eye of patients with an idiopathicfull-thickness macular hole. Methods: The fellow eyes of 189 patients who underwent idiopathic full-thickness macular hole surgery were examinedby biomicroscopy and spectral domain-optical coherence tomography (SD-OCT). A subset of 21 fellow eyes with a stage 0macular hole was observed. Changes in the macular hole were evaluated by biomicroscopy and SD-OCT for an average of 29months. Results: Among the 21 eyes, 15 showed no change in perifoveal vitreous detachment (71.4%). Two eyes (9.5%) developedcomplete vitreofoveal separation, and one of the two developed a separation after progression to stage 1A. Among 21 eyes,5 (23.8%) developed above stage 1A, and one of the five progressed to stage 1B after five years, which was successfullytreated with vitrectomy and gas tamponade. Conclusions: Perifoveal vitreous detachment in the fellow eye on SD-OCT, defined as a stage 0 macular hole, occurred at anearlier phase than stage 1A macular holes and may progress to an advanced stage. Therefore, patients who undergo macularhole surgery and have a stage 0 macular hole or perifoveal vitreous detachment in the fellow eye should be followed closely.

Long-Term Clinical Outcomes of Iliac Artery Endovascular Therapy in the Korean Vascular Intervention Society Endovascular Therapy in Lower Limb Artery Diseases (K-VIS ELLA) Registry

Ji Woong Roh,Sanghoon Shin,Young-Guk Ko,Nak-Hoon Son,Chul-Min Ahn,Pil-Ki Min,Jae-Hwan Lee,Chang-Hwan Yoon,Cheol Woong Yu,Seung Whan Lee,Sang-Rok Lee,Seung Hyuk Choi,In-Ho Chae,Donghoon Choi 대한심장학회 2022 Korean Circulation Journal Vol.52 No.7

Background and Objectives: Limited data are available regarding long-term clinical outcomes of iliac artery endovascular therapy (EVT) in real-world practice. This study investigated long-term outcomes according to Trans-Atlantic Inter-Society Consensus (TASC) classifications. Methods: We analyzed data from 1,705 limbs of 1,364 patients from the retrospective cohort of the multicenter Korean Vascular Intervention Society Endovascular Therapy in Lower Limb Artery Disease registry. The primary endpoint was target lesion revascularization (TLR)-free survival. Results: TASC A, B, C, and D lesions were present in 19.4%, 26.2%, 28.7%, and 25.7% of the treated limbs, respectively. The technical success rate was 96.2% and did not differ between TASC lesion types. Complications occurred in 6.8% of cases and more occurred in TASC D (11.8%). Iliac artery EVT showed a 5-year TLR-free survival of 89.2%. The TASC D group had the lowest TLR-free rate of 79.3%. TASC D (hazard ratio [HR], 1.75; 95% confidence interval [CI], 1.12–2.73; p=0.014), plain old balloon angioplasty (HR, 4.25; 95% CI, 2.03–8.88; p<0.001), current smoker (HR, 1.89; 95% CI, 1.26–2.83; p=0.002), previous bypass surgery (HR, 3.04; 95% CI, 1.28–7.19; p=0.011), combined femoropopliteal treatment (HR, 4.89; 95% CI, 3.19–7.50; p<0.001), combined below the knee treatment (HR, 2.20; 95% CI, 1.25–3.89; p=0.007), and complications (HR, 1.86; 95% CI, 1.07–3.24; p=0.028) were predictors for TLR. Conclusions: Iliac artery EVT achieved excellent technical success and 5-year TLR-free survival. TASC D showed a favorable but lower 5-year TLR-free survival rate and higher complication rate compared with other TASC groups.

Change of gangliosides pattern and expression of glycosyltransferase genes in mouse embryonic fibroblasts induced pluripotent stem (miPS) cells

Jae-Sung Ryu,Jeong-Woong Lee,Dong Hoon Kwak,Ji-Su Kim,in-Hyoung Cho,So-Dam Lee,So-Hyun Lee,Ju-Taek Lee,Kyu-Tae Chang,Young-Kug Choo 한국당과학회 2011 한국당과학회 학술대회 Vol.2011 No.1

Gangliosides are complex glycosphingolipids that contain one or more sialic acids, the major components of cytoplasmic cell membranes. These are thought to play a role in the control of biological process including cell surface interaction, cell differentiation and transmemebrane signaling. In this study, we demonstrated that change of gangliosides pattern and glycosyltransferase gene in mouse induced pluripotent stem cells (miPSCs). The miPSCs were derived from OG2 mouse embryonic fibroblasts (mEFs) using retrovirus-mediated delivery and expression of Oct-4, Sox-2, Klf-4 and c-Myc. These cells were expressed alkaline phosphatase (AP), stage specific embryonic antigen-1 (SSEA-1) and mRNA such as Oct-4, Sox-2 and Nanog. In HPTLC and immunochemistry analysis, ganglioside GM3 and GD1a were expressed in mEFs, miPSCs and mESCs. However, only GM2 and GM1 were expressed in mEFs and mESCs. Ganglioside GM3 and GD3 expression level was low in miPSCs. Moreover, A2B5 antigen, c-series gangliosides such as GT3 and GQ1c, was only expressed in mESCs. To provide a better understanding of the metabolic basis of glycosyltransferase genes expressions, we analyzed expression of glycosyltransferase genes in mEFs, miPSCs and mESCs, and found that expression of sialyltransferase-I (ST-I), ST-II, ST-III, N-acetylgalactosamine transferase (GalNAcT), galactosyltransferase-II (Gal-II), ST-IV and ST-V. However, ST-II was not only expressed in mEFs. These results suggest that ganglioside GM3 and GD1a unique and powerful cell-surface biomarker to identify of mESCs and miPSCs, and change of ganglioside expression could be affected by gangliosides synthase activation. Therefore, gangliosides may play a role in the cell differentiation process.

Original Articles : The Clinical Outcomes of Proton Beam Radiation Therapy for Retinoblastomas That Were Resistant to Chemotherapy and Focal Treatment

( Ji Woong Chang ),( Young Suk Yu ),( Joo Young Kim ),( Dong Ho Shin ),( Jin Choi ),( Jeong Hun Kim ),( Seong Joon Kim ) 대한안과학회 2011 Korean Journal of Ophthalmology Vol.25 No.6

Purpose: To evaluate the clinical results of proton beam radiation therapy (PBRT) for treatment of retinoblastoma. Methods: Children with retinoblastoma who were treated with chemotherapy and focal treatment such as brachytherapy and thermotherapy but showed no response or developed recurrences later received PBRT. The PBRT strategy was designed to concentrate the radiation energy to the retinoblastoma and spare the surrounding healthy tissue or organs. Results: There were three patients who received PBRT. The first patient received PBRT because of an initial lack of tumor regression with chemotherapy and brachytherapy. This patient showed regression after PBRT. The second patient who developed recurrence of retinoblastoma as diffuse infiltrating subretinal seeding was taken PBRT. After complete regression, there was recurrence of tumor and the eye was enucleated. The third patient had unilateral extensively advanced retinoblastoma. Initial chemotherapy failed and tumor recurred. The tumor responded to PBRT and regressed significantly. However, the eye developed sudden multiple recurrences, so we had to perform enucleation. Conclusions: PBRT for retinoblastoma was effective in cases of showing no response to other treatment modalities. However, it should be carefully applied when there was recurrence of diffuse infiltrating subretinal seeding or extensively advanced retinoblastoma initially.

Congenital Aniridia: Long-term Clinical Course, Visual Outcome, and Prognostic Factors

( Ji Woong Chang ),( Jeong Hun Kim ),( Seong-joon Kim ),( Young Suk Yu ) 대한안과학회 2014 Korean Journal of Ophthalmology Vol.28 No.6

Purpose: To describe the clinical course of congenital aniridia and to evaluate prognostic factors for visual outcome after long-term follow-up. Methods: The medical records of 120 eyes from 60 patients with congenital aniridia were retrospectively reviewed. The prevalence and clinical course of ophthalmic characteristics, systemic disease, refractive errors, and visual acuity were assessed. Prognostic factors for final visual outcomes were analyzed. Results: Aniridic keratopathy developed in 82 (69%) of 119 eyes. Macular hypoplasia was observed in 70 eyes of 35 patients (91%). Cataract was observed in 63 of 120 eyes (53%). Nystagmus was present in 41 patients (68% of 60 patients) at the initial visit but decreased in five patients (8% of 60 patients). Ocular hypertension was detected in 19 eyes (20% of 93 eyes), six (32% of 19 eyes) of which developed secondarily after cataract surgery. The mean changes in spherical equivalent and astigmatism during the follow-up period were -1.10 and 1.53 diopter, respectively. The mean final visual acuity was 1.028 logarithm of minimal angle of resolution. Nystagmus and ocular hypertension were identified as prognostic factors for poor visual outcome. Conclusions: Identification of nystagmus and ocular hypertension was important to predict final visual outcome. Based on the high rate of secondary ocular hypertension after cataract surgery, careful management is needed.

Meniscus-Controlled Water-Based Assembly of Sphere Particles for Chemical Vapor Detection

Chang, Ji Woong,Kim, Hyun Jae,Kim, Jaekyun American Scientific Publishers 2017 Journal of nanoscience and nanotechnology Vol.17 No.11

<P>Conductivity-based sphere sensors for chemical sensing were fabricated using a bottom-up approach. The capillary force at the meniscus was used to precisely position poly(3,4-ethylenedioxythiophene) (PEDOT) nanoshell sphere sensors at the predefined locations of a cross-point array structure for electrical contact and analyze detection. The combination of bottom-up assembly and top-down structure not only provides a method to fabricate an ultrahigh density sensor array with an extreme redundancy for the high sensitivity, but also offers the intriguing potential to assemble various types of sensor element at precisely controlled locations for an electronic nose system.</P>