Lithographically-featured photonic microparticles of colloidal assemblies

Lee, Su Yeon,Kim, Shin-Hyun,Heo, Chul-Joon,Hwang, Hyerim,Yang, Seung-Man Royal Society of Chemistry 2010 Physical Chemistry Chemical Physics Vol.12 No.38

<P>We have described a new and promising strategy for the fabrication of composite and porous photonic crystal microparticles that combines the self-assembly of colloidal particles with photolithography techniques. We fabricated silica/SU-8 composite microparticles with photonic bandgaps <I>via</I> four steps: (1) deposition of the silica colloidal crystals on the photoresist, (2) embedding of the colloidal crystals in the photoresist, (3) UV exposure through a photomask and subsequent development, and (4) release of the microparticles from the substrate. Embedding was performed above the glass transition temperature (<I>T</I><SUB>g</SUB>) of uncrosslinked SU-8. At such temperatures, capillary forces on the silica particles facilitate the migration of colloidal crystals in the SU-8 matrix. Particle migration ceased when the top colloidal crystal layer was trapped at the interface between air and SU-8. In addition, we also prepared porous microparticles with an inverse opaline structure by dissolving the embedded silica particles from the composite structures. The porous microparticles showed enhanced reflectivity at the bandgap position due to the large refractive index contrast. The bandgap position of the microparticles was controlled by the size of the silica particles, which determined the lattice constant. Bilayered composite and porous microparticles with two distinct photonic bandgaps were also prepared by sequential deposition of colloidal crystals composed of two differently sized silica particles.</P> <P>Graphic Abstract</P><P>A new and promising fabrication strategy of photonic crystal microparticles was demonstrated by combining colloidal self-assembly with photolithography. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0cp00134a'> </P>

비만을 동반한 위암 환자에서 두 병을 같이 수술 치료한 경험(증례)

최경현,윤기영,문형환,신연명,서경원,안수미,송윤미,석정희,정경연,이은하 고신대학교의과대학 2008 고신대학교 의과대학 학술지 Vol.23 No.3

Obesity is growing problem in Korea. We had a case of bariatric surgery during gastric cancer operation. Patient was 29 year old Korean lady with early gastric cancer located in the lesser curvature side of the middle 1/3 of the stomach. Her body weight was 89 kg, height 163 cm, and thus body mass index was 33.5 kg/m2. Preoperative blood pressure was 130/90 mmHg, hemoglobin 12.9 g/dL, total lymphocyte count 3,280/mL, serum albumin 4.3 g/dL, CEA 1.1 ng/mL, CA 19-9 9.1 ng/mL, and alpha fetoprotein 2 ng/mL. Another associated disease was right thyroid follicular neoplasm. The chest X-ray was normal. After IM injection of 2,500 units of heparin 30 minutes before the induction of general anesthesia, she received curative subtotal gastrectomy and Roux en Y gastrojejunostomy when a malabsorption loop of 120 cm jejunum was incorporated between the Treitz ligament and the end to side jejuno-jejunostmy site at May 29th 2006. Her postoperative course was uneventful except a minor wound seroma and the elevations of serum amylase(up to 4 folds) and lipase(up to 2 folds). She lost her body weight 9 kg in 5th, 21 kg in 7th, and 27 kg in 10th postoperative months to became 61.5 kg. On follow up exams in July 2008, she gained 4 kg to overcome her weakness and fatigue. From the above result, the incorporation of a malabsorption loop during reconstruction phase of gastric cancer operation was a good option for obese gastric cancer patients especially in cases of early gastric cancer.

Effect of Platelet-Rich Fibrin on Repair of Defect in the Articular Disc in Rabbit Temporomandibular Joint by Platelet-Rich Fibrin

( Hyun Su Baek ),( Hye Sung Lee ),( Bok Joo Kim ),( In Kyo Chung ),( Chul Hoon Kim ),( Sun Mi Jin ),( Hie Sung Hwang ),( Sang Hun Shin2 ) 한국조직공학·재생의학회 2011 조직공학과 재생의학 Vol.8 No.6

The objective of this study was to evaluate platelet-rich fibrin (PRF)’s effectiveness in repairing articular disc defect in the temporomandibular joint (TMJ) of rabbits. Eight rabbits were divided into four groups of two rabbits each, corresponding to groups A, B, C, and D. Both TMJs of all of the rabbits were used in the experiments: the right joints comprised the experimental groups, and the left ones, the control groups. The disc defect was circular and 2 mm in diameter. In the experimental groups, the PRF was compressed into the defect, whereas the control group defects were left untreated. A, B, C, and D groups were sacrificed at the 1st, 2nd, 4th and 6th weeks, respectively. The defects of each control group exhibited no specific changes. Contrastingly, in each experimental group, there was an increased number of chondroblasts at the margins of the defects, along with accelerated cell differentiation and a columnar cell arrangement observable at the time of cell differentiation. The experimental groups showed inflammatory cell infiltrations and fibrosis by the 1st week, maturation of chondrocytes by the 2nd week, and proliferation by the 4th week, after which the defects began to be filled with chondrocytes, a process that was complete after the 6th week. In the histological evaluation (H-E), the experimental groups showed significant increases of chondroblasts after the 2nd and 4th weeks, as well as regular columns of chondrocyte arrays observable during cell division. After 6 weeks, the defects were filled with chondrocytes.

광주광역시 치매의 유병률과 위험인자의 도시-농촌 지역 비교

신일선,김재민,윤진상,김석재,양수진,김웅장,이승현,강순아,곽지영,이형영 大韓神經精神醫學會 2002 신경정신의학 Vol.41 No.6

연구목적 : 본 연구의 목적은 광주광역시의 도시 및 농촌 지역에 거주하는 노인에서 치매의 유병률과 위험인자를 조사하고자 하였다. 부가적으로 이 두 지역간에 치매의 유병률과 위험인자를 비교하고자 하였다. 방 법 : 광주광역시의 전형적인 도시와 농촌지역의 65세 이상의 노인(N=1,598)을 대상으로, 2단계의 역학연구를 수행하였다. 1차 선별 단계에서는 38명의 훈련된 연구보조원이 대상노인을 면담하여, 사회인구학적 특징을 조사하고 한국판 간이정신상태검사(Korean version of Mini-Mental State Examination ; MMSE-K)로 평가하였다. 2차 임상 진단 단계에서는 1차 단계에서 MMSE-K 점수가 24점 이하인 노인(N=431)을 대상으로, 전문연구팀의 임상적 평가를 통해 치매를 진단하고 원인질환별로 알쯔하이머병(Alzheimer's disease ; AD), 혈관성 치매(vascular dementia ; VaD) 및 기타 치매로 분류하였다. 대상노인에서 치매의 유병률을 측정한 후, 광주광역시 전체 노인의 연령보정 유병률을 산출하였다. 전체 대상에서 AD의 위험인자를 조사한 후, 도시와 농촌군으로 나누어 분석을 다시 시행하였다. 결 과 : 1차 및 2차 단계의 참가율은 각각 71.0%(N=1,134) 및 83.2%(N=410) 였다. 연구 참여 노인(N=1,134)에서 전체 치매, AD 및 VaD의 유병률은 최소 각각 9.7%, 5.2%, 1.8%였다. 광주광역시 전체 노인의 연령 보정 유병률은 각각 10.7%, 5.7%, 1.9%인 것으로 산출되었다. AD의 독립 위험인자는 고령, 여성, 무학이었다. 도시와 농촌에 따른 유병률의 차이는 파악되지 않았다. 그러나 AD의 위험인자는 지역에 따라 차이가 있었다. 도시 노인에게는 무학만이, 농촌 노인에게는 고령과 여성인 경우가 독립 위험인자였다. 결 론 : 광주광역시 노인에서 치매의 유병률은 높았고, 이는 국내 다른 지역에서 수행된 선행연구 결과와 유사하였다. 알쯔하이머형 치매의 위험인자는 도시와 농촌에 따라 다른 결과를 보였다. 본 연구 결과는 한국에서의 치매의 실태를 반영하며, 치매의 적절한 관리와 예방을 위해서는 지역성 특성이 고려되어야 함을 시사한다. Objectives : The purpose of this study was to investigate the prevalence rate and risk factors of dementia in an urban and a rural sample of older persons in the metropolitan Kwangju area, Republic of Korea. In addition, the prevalence rate and risk factors of dementia between the two samples were compared. Methods : A two-phase epidemiological study of residents aged 65 or over(N=1,598) was conducted in a highly developed, urban and a non-contiguous, poorly developed, rural area of metropolitan Kwangju. In the first(screening) phase, 38 trained research assistants collectively peformed in-home interviews for all participants. Detailed sociodemographic characteristics were gathered and the Korean version of Mini-Mental State Examination (MMSE-K) was administered. In the second (diagnosing) phase, diagnosis of dementia was established for those scoring 24 or less on the MMSE-K in the screening phase(N=431), and etiological types of dementia were classified to Alzheimer's disease(AD), vascular dementia(VaD) or miscellanous type by two teams of experts. Prevalence rate of dementia was determined in the participants, and age-standardized prevalence rate adjusted by age distribution in metropolitan Kwangju was estimated. For AD, the risk factors were investigated in all participants, and analyses were repeated for the urban and rural samples separately. Results : The participating rates in the first and second phases were 71.0%(N=1,134) and 83.2%(N=410), respectively. In the participants, the prevalence rates of dementia(all types), AD and VaD were 9.7%, 5.2% and 1.8%, respectively. The age-standardized prevalence rates were 10.7%, 5.7% and 1.9%, respectively. Aging, female gender and no education(complete lack of formal education) were identified as independent risk factors for AD. No difference between the urban and rural samples was observed in the prevalence rates of dementia(all types), AD and YaD. However, risk factors for AD differed between these areas. In the urban sample, no education was the only significant factor ; whereas, aging and female gender were identified as risk factors in the rural sample. Conclusion : A high prevalence rate of dementia was observed among old persons in metropolitan Kwangju, consistent with previous studies conducted in other Korean areas. The risk factor profi1es for AD differed between urban and rural settings. The results of this study reflect the current status of dementia in Korea and suggests that appropriate management and prevention strategies for dementia should be tailored toward the geographic settings.

대학생 학습과정 조사도구의 비교·분석 연구

신현석,변수연,박해경 한국교육방법학회 2012 교육방법연구 Vol.24 No.1

Higher education institutions in the 21st century are feeling more and more pressure to show and prove their due accountability toward the society. The fulfillment of their social responsibilities can be accomplished by teaching and research. The quality of teaching in higher education institutions have been approached from various perspectives and tried to be measured by different methods. Among others, students' evaluation and ratings have been viewed as useful tools to evaluate the quality of education and supporting services of the institutions. This study analyzed 5 aspects of the three major student's evaluation and engagement questionnaires: National Survey of Student Engagement, Course Experience Questionnaire, Australian Survey of Student Engagement. In comparative analysis, researchers concluded CEQ has several shortcomings to be an efficient and effective student engagement scale while it still has some merits such as offering a opportunity to every college graduate to evaluate their college teaching experience. NSSE and AUSSE, taking the sample study framework, are reviewed to be easier to be administrated and contain more plentiful information about various facets of college students' experience and its relationship with achievements in college. This findings are expected to offer useful implications to those who develop the Korean scale of student experience and engagement. 본 연구는 세계적으로 사용되고 있는 대학생 학습과정 조사도구들 중 NSSE, CEQ, AUSSE의 개발 배경과 변천 과정, 개발 목적, 주요 내용, 결과의 활용 다섯 가지 측면을 조사한 후 이를 비교․분석함으로써 우리나라 고등교육기관의 대학생 학습과정 조사도구 개발을 위한 정책적 시사점을 제안하는 것을 목적으로 한다. 이들을 비교한 결과 다섯 가지 준거를 통한 비교․분석 결과 대학 강의 경험을 주요 내용으로 하는 전수조사 방식의 CEQ보다는 강의와 강의실 밖의 다양한 학습 기회에 대한 학생 참여도를 기준으로 대학생의 학습과정과 대학 교육의 질을 평가하는 표본조사 방식의 NSSE와 AUSSE가 우리의 고등교육 시스템에 더 적합할 뿐만 아니라 국제적 비교․분석도 가능한 조사도구로 평가되었다.

국내 조혈모세포이식 환자에서 Human Cytomegalovirus gB 유전형의 분포와 질환과의 연관성 : 예비 보고

최수미,김진희,이동건,박선희,최정현,유진홍,박철민,이종욱,민우성,황응수,신완식,김춘추 대한감염학회 2007 감염과 화학요법 Vol.39 No.2

목적 : 사람 거대세포바이러스(Human cytomegalovirus, 이하 HCMV) glycoprotein B (gB)는 UL55 유전자에 의해 부호화되는 당단백으로, UL55 유전자의 염기서열변화에 따라 4가지 유전형으로 나뉜다. 본 연구에서는 국내 조혈모세포이식 환자들에서 HCMV gB 유전형의 분포와 그 특성을 알아보고, gB 유전형에 따라 특정 HCMV 질환 발생과 연관이 있는지 그 임상적 의미를 분석해 보고자 하였다. 재료 및 방법 : 동종 조혈모세포이식 환자 52명의 혈액검체 94개에 대해, Chou 등이 제시한 방법에 따라, 먼저 UL55 유전자 부위를 nested PCR로 증폭한 후, RsaI과HinfI으로 Restriction fragment length polymorphism(RFLP) 분석을 시행하였다. 결과 : gB type 1은 73.1% (38/52), gB type 2는 13.5%(7/52), gB type 3는 1.9% (1/52), gB type 1과 type 2에 의한 혼합감염은 9.6% (5/52)로 나타났다. gB type 4는 관찰되지 않았다. 1명(1.9%)에서 gB 유전형을 결정할 수 없었는데, RFLP 패턴으로 보아 Trincado 등이 제시한 gB type 7에 해당하는 것으로 생각되었고, 이 새로운 아형에 대해서는 현재 염기서열 분석 중이다. 52명 중 5명(9.6%)에서 HCMV 질환이 발생하였고, 3명에서 HCMV 폐렴, 1명에서 망막염과 위장관염, 나머지 1명에서 망막염이 발생하였다. 5명 중 HCMV 질환과 관련하여 사망한 예는 없었고, 감염된 HCMV는 모두 gB type 1이었다. HCMV gB유전형과 HCMV 질환 발생 사이에 유의한 연관성은 없었고, 단일 주에 의한 감염과 혼합감염에 따른 HCMV 질환발생 사이에도 유의한 연관성은 관찰되지 않았다. 자료 분석 중 gB type 2에 감염되어 있던 환자에서 gB type 1에 재감염 되면서 발열, 간효소 수치 상승 및 pp65 HCMV 항원혈증이 나타난 예가 있었다. 결론 : 연구결과 gB type 1이 아주 우세하고, gB type 4는 검출되지 않았으며, 혼합감염의 빈도가 비교적 낮은 분포를 보였다. 이는 외국의 보고와는 다른 국내 조혈모세포이식 환자에서의 독톡한 감염 양상으로 추정된다. 본 연구에서 HCMV gB 유전형과 질환 발생과의 연관성을 밝힐 수는 없었으나, HCMV 유전형에 대한 연구는 바이러스 감염의 발병기전이나 전파 경로 및 양식과 같은 역학적 연구에 중요한 자료가 될 것이다. 현재 더 많은 수의 조혈모세포이식 환자를 대상으로 연구가 진행 중에 있으며, 앞으로 다른 질환군의 환자나 건강한 잠복 감염자에서의 추가 연구가 필요할 것으로 생각된다. Background : Human cytomegalovirus (HCMV) glycoprotein B (gB) is the major envelope glycoprotein, encoded by the UL55 gene. Based on sequence variation in the UL55 gene, HCMV can be classified into four gB genotypes. Previous studies have suggested an association between HCMV gB genotypes and clinical outcome in the immunocompromised hosts. The goal of this study was to determine the distribution of HCMV gB genotypes and the effect of gB genotype in the developement of HCMV diseases in hematopoietic stem cell transplant (HSCT) recipients in Korea. Materials and Methods : DNA was extracted from 94 blood specimen of 52 allogeneic HSCT recipients with HCMV infection. HCMV gB genotype was determined using polymerase chain reaction to amplify a region of UL55, followed by restriction fragment length polymorphism (RFLP) analysis based on RsaI and HinfI digestion. Results : The distribution of gB types were as follows: gB1, 73.1% (38/52) of patients; gB2, 13.5% (7/52); gB3, 1.9% (1/52) and mixed infection (gB1 and gB2), 9.6% (5/52). While gB4 was not detected, a new genotype (described as gB7 by Trincado et al, 2000) was identified on the basis of their RFLP pattern. During average 708 days’ follow up period, HCMV diseases developed in 5 patients. All of them had gB1 genotype. There was no statistically significant association between the incidence of HCMV diseases and the gB genotypes. Re-infection with gB1 strain was detected in one patient who had been previously infected with gB2. This episode was associated with fever, elevated liver enzyme and positive antigenemia. Conclusion : HCMV gB1 was the dominant genotype and no gB4 was detected in allogeneic HSCT recipients in Korea, which is an unique pattern compared with the previous reports. Although we can not find significant association between the HCMV diseases and the gB genotypes, genotyping of HCMV will serve in the study of pathogenesis and transmission of this virus in transplant patients. Further study is underway with large study population.

전류제어에 의한 단상유도전동기의 기동특성 개선

박수강,최낙일,백형래,임양수,이기용,신사현 조선대학교 에너지.자원신기술연구소 1998 에너지·자원신기술연구소 논문지 Vol.20 No.1

A single phase induction motor(SPIM) with two windings, main and auxiliary, is probably the most widely used motor in the world due to their ruggedness, low maintenance and simplicity of construction There are several ways of starting single phase motors The most popular arrangements is centrifugal switch An auxiliary winding connected in series with a capacitor, is brought into the circuit during starting The closing and opening of the switch must be speed dependant The switch meets the speed requirements, but it also has many drawback random switching, arcing, many models necessary for different speeds and shaft diameters, space required inside the motors and limited lifetime to name some of them. In this paper, the starting current of single phase induction motor was detected by a small detector and determined TRIAC gate signal. The strategy of current control is based on limited main and auxiliary current angle during starting period in the closed-loop control. The experimental result show the motor's starting characteristics of the proposal starting system and are compared with centrifugal switch starting motor.

소아 뇌성마비의 조기 진단 및 조기 수술적 치료

이건수,변상현,신현대,송시헌 충남대학교 의학연구소 2001 충남의대잡지 Vol.28 No.2

Cerebral palsy is a static encephalopathy that is caused by multifactorial disorders. Treatment should be approached by a team of physicians from various specialties. But usually the detection of abnormal behavior might be delayed. We used Bayley scales for the patients which were transfered for the evaluation of behavior disorder and tried to detect earlier as cerebral palsy. We recommended selective posterior rhizotomy to the patients who was spastic quadriplegia as early as possible. We evaluated 154 patients with Bayley scale and 85 patients were followed. Among them we applied selective posterior rhizotomy to 25 patients who were spastic quadriplegia. The result was very excellent. We conclueded that Bayley scale is a good tool for evaluation of developmental delay esp. cerebral palsy earlier than usual physical examination and selective posterior rhizotomy is satisfactory treatment method for spastic quadriplegia.

국내 혈액질환 환자에서 침습성 진균 감염의 구제치료로서 Caspofungin의 효과와 안전성

최수미,박선희,이동건,최정현,유진홍,민우성,신완식,김춘추 대한감염학회 2005 감염과 화학요법 Vol.37 No.5

목적 : 본 연구에서는 국내 혈액질환 환자들에서 일차 항진균제를 부작용으로 인해 투여할 수 없거나, 일차 항진균제에 반응이 없는 침습성 진균 감염증의 구제치료로서 caspofungin의 효과와 이상반응에 대한 임상 경험을 소개하고, 예후인자를 분석해 보았다. 재료 및 방법 : Caspofungin은 첫날 70 mg, 이틀째 부터 50 mg을 하루 일회 투여하였고, caspofungin 종료시 그리고 종료 4주 후 반응을 평가하였다. 결과 : 총 55명의 환자가 분석에 포함되었고, 남자 32명, 여자 23명, 평균 나이는 38.2세(16-65세)였다. 기저 질환은 급성 백혈병 33명, 골수이형성 증후군 12명, 만성 백혈병 3명, 기타 7명이었다. 진균 감염은 확진 1명, 가능 5명, 추정 47명, 불확실 2명이었고, 감염 장소는 폐를 침범한 경우가 49명, 파종감염 6명이었다. 전체적으로 41.8% 환자에서 양호한 반응을 보였으며, 치료군, 치료후 기저질환의 상태, 침습성 진균 감염 진단시 호중구 감소증 여부, 스테로이드 등 면역억제제 사용 여부가 유의한 예후인자였다. 약제관련 이상반응은 14.5%에서 관찰되었고, 발열, 피부 발진, 간기능 저하 등으로 나타났다. 이중 4명에서 이상반응과 관련하여 투약을 중지하였고, 약제 중단 후 증상은 모두 호전되었다. Caspofungin 관련 신독성은 관찰되지 않았다. 결론 : Caspofungin은 국내 혈액질환 환자에서 침습성 진균 감염증의 구제치료에 효과적으로 안전하게 사용될 수 있겠다. 최근 여러 항진균제들이 개발되어 임상에 도입되고 있는 바, 항진균 작용 범위, 독성, 약역동학적 특성, 비용-효과면 등을 고려하여 환자별로 직절한 항진균제를 선택하도록 해야 할 것이다. Background : Invasive fungal infection (IFI) is an important cause of morbidity and mortality in patients with hematologic malignancy. Patients with IFI who fail to standard therapy have poor prognoses. We investigated the efficacy and safety of caspofungin (CAS) in Korean adults with hematologic diseases and IFI who did not respond to the conventional antifungal therapy. Materials and Methods : Patients with IFI refractory or intolerant to standard antifungal therapy received CAS 50 mg IV daily after 70 mg loading dose on day 1. Efficacy and safety of CAS were assessed in patients who received more than one dose. Favorable response [complete (CR) or partial (PR)] was defined as significant improvement of all clinical symptoms, signs, and radiologic abnormalities. Results : From Feb. 2004 to Feb. 2005, 55 patients who met the inclusion criteria were enrolled. There were 32 male and 23 female patients with mean age of 38.2 years (range, 16-65). Underlying diseases were acute leukemia (33 cases), myelodysplastic syndrome (12 cases), chronic myelogenous leukemia (3 cases), and other hematologic diseases (7 cases). Thirty-six patients were receiving chemotherapy and 13 patients were under hematopoietic stem cell transplantation (HSCT). The number of proven, probable, possible, and indeterminate IFI cases was 1, 5, 47, and 2, respectively. Conventional amphotericin B, intravenous itraconazole, and liposomal amphotericin B were administered for average of 14.9 days prior to administering CAS. Mean duration of CAS therapy was 12.8 days (range, 1-45). Twenty-three patients (41.8%) showed favorable responses (CR : PR=8 : 15) at the end of CAS therapy. Chemotherapy group, neutropenic state, remitted state of underlying disease, and no steroid therapy were significant prognostic factors for favorable response. Eight (14.5%) patients developed drug-related adverse events such as fever, skin eruption, and hepatic dysfunction which were reversible after discontinuation of CAS. Drug-related nephrotoxicity was not observed. Conclusion : On the basis of our investigation, CAS was effective and safe as a salvage therapy of refractory IFI or as an alternative for patients intolerant to standard antifungal agents.

프로야구 투수들의 견관절 회전근에 대한 등속성 수축력 근기능 평가

김수현,한경진,신범철 韓國體育大學校附屬 體育科學硏究所 1997 韓國體育大學校附屬 體育科學硏究所論文集 Vol.16 No.1

The purpose of this study was t investigate isokinetic functional strength evaluation of shoulder rotational strength in korean professional baseball pictchers. Healthy professional elite pitchers(8 males) participated in this study. In order to mearsure the isokinetic peak torque, ER/IR ratio, PK%BW ratio, total work, peak torque acceleration energy, mean power, endurance ratio, we examined the both upper extremities of subjects at the angular velocity 60。/sec, 120。/sec, 180。/sec. The major results are as follows ; 1. There was meaningful statistical difference(P<.05, P<.01) between dominant side and non-dominant side in peak torque of the internal shoulder rotators at 120。/sec, 180。/sec speed. 2. There was meaningful statistical difference(P<.05), between dominant side and non-dominant side in peak torque % body weight of the internal shoulder rotators at 120。/sec speed. 3. There was meaningful statistical difference(P<.01, P<.05) between dominant side and non-dominant side in total work of the internal and external shoulder rotators at 180。/sec speed. 4. There was meaningful statistical difference(P<.01) between dominant side and non-dominant side in mean power of the internal shoulder rotators at 180。/sec speed.