• Title/Summary/Keyword: PFA

Search Result 148, Processing Time 0.025 seconds

Clinical Use of PFA®-100 in Pre-surgical Screening for Platelet Function Test (수술 전 혈소판 기능 검사를 위한 PFA®-100의 임상적 이용)

  • Kim, Sung-Man;Yang, Seung-Bae;Lee, Jehoon
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.41 no.1
    • /
    • pp.1-5
    • /
    • 2009
  • The Platelet Function Analyzer (PFA)$^{(R)}$-100 measures the ability of platelets activated in a high-shear environment to occlude an aperture in a membrane treated with collagen and epinephrine (CEPI) or collagen and ADP (CADP). The time taken for the flow across the membrane to stop (closure time, CT) is recorded. The aim of this study was to assess the potential of the PFA$^{(R)}$-100 as a primary clinical screening tool using the wide spectrum of clinical samples assessed for platelet function as well as to perform the optimal algorithm for the use of PFA$^{(R)}$-100. We established the reference interval in 460 hospital inpatients defined as having normal platelet function based on classical laboratory tests. The reference interval by using the range $5^{th}$ and $95^{th}$ percentile was 84~251 seconds for males CEPI-CT and 85~249 seconds for females CEPI-CT. A total of 1,200 inpatients were enrolled to identify impaired hemostasis before surgical interventions. The abnormal group showing prolonged CEPI-CT was 303 cases (18.9%). Only 3 cases had both abnormal CEPI-CT and CADP-CT. Several factors including sample errors, drugs, hematologic abnoralities were contributed to unexpected prolonged CEPI-CT for screening test. The von Willebrand factor (vWF:Ag) assay was performed only in one patient to verify the algorithm for the use of PFA$^{(R)}$-100. The PFA$^{(R)}$-100 was sensitive and rapid method for primary screening test of platelet dysfunction, so we can substitute it for the bleeding time in routine clinical practice.

  • PDF

Research on Frequency Average Analysis of vibrational Power Flow Analysis (진동파워흐름해석의 주파수 평균해석에 대한 연구)

  • Lee, Jea-Min;Hong, Suk-Yoon;Park, Young-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.05a
    • /
    • pp.971-977
    • /
    • 2005
  • Power Flow Analysis (PFA) is developed for the effective predictions of frequency-averaged vibrational response in medium-to-high frequency ranges. In PFA, the power coefficients of semi-infinite structure and for-field energy density are used to predict the vibrational responses of structures. Generally, at high frequencies, PFA can predict narrow-band frequency-averaged vibrational responses of built-up structures. However, in low- to medium frequency ranges, the dynamic responses obtained by PFA represent broad-band frequency-averaged vibrational energy densities. For the prediction of vibrational response variance in Power Flow Finite Element Method (PFFEM), the variances of input power and joint element matrix describing structural coupling relationship are derived. Finally, for the validity of developed formulation, numerical examples for two co-planer plates are performed and the vibrational response variance of the structure are compared with the results of classical and PFFEM solutions.

  • PDF

Relationship Between Problem Finding Ability and Problem Solving Ability in Chemistry (문제발견 능력과 화학 문제해결 능력과의 관계)

  • Ryu, Si-Gyeong;Park, Jong-Seok
    • Journal of the Korean Chemical Society
    • /
    • v.52 no.2
    • /
    • pp.179-185
    • /
    • 2008
  • purpose of this study is to investigate the relationship between high school students' Problem Finding Ability (PFA) and chemistry problem solving ability. To achieve this purpose, the interrelationship between the results of PFA in ill-structured scientific problem situation and the scores of sham examination in chemistry I of College Scholastic Ability Test (CSAT) was analyzed. The results of this study turned out to be as follows: There was correlation (r=.346) between the score of PFA test and that of sham examination in chemistry I of the CSAT. And a little correlation (r=.390) between PFA and students application ability which is one of the sub factors in sham examination of the CSAT. Especially, in the high achievers group there was high correlation (r=.446) between students fluency which is one of the sub factors in PFA, and application ability. This implies that the application ability of high achievers has something to do with their PFA for a variety of problems. As for the PFA between high achievers and low achievers, there was no significant difference (t=.830, p=.411).

A Mixture of Thyme, Quillaja, and Anise at Different Nutrient Density on Growth Performance, Nutrient Digestibility, Meat Quality, Organ Weight, Cecal Bacteria, Excreta Moisture, and Bone Contents in Broiler Chicks

  • Serpunja, Subin;Abdolreza, Hosseindoust;Kim, In Ho
    • Korean Journal of Poultry Science
    • /
    • v.44 no.3
    • /
    • pp.151-159
    • /
    • 2017
  • The experiment was carried out on 648 Ross 308 broilers ($40.4{\pm}0.2$ g; 1 d) chickens. It lasted for 28 days to evaluate the effects of phytogenic feed additive (PFA) on growth performance, nutrient digestibility, cecum microbiota, bone minerals contents, meat quality and internal organ weights. The chickens were haphazardly divided into any 1 of 6 dietary treatments (6 replicate pens/treatment; 18 broilers/pen). The experimental diets were: CON, control; T1, CON + 150 ppm PFA; T2, CP 0.5% reduced from basal diet; T3, T2 + 150 ppm PFA; T4, Ca 0.07% reduced + available P (aP) 0.065% reduced from basal diet; T5, T4 + 150 ppm PFA. Overall, broilers fed with T3 diet tended to have higher (P=0.08) body weight gain (BWG), and lower (P=0.05) feed conversion ratio (FCR) than T2 diet. The apparent total tract digestibility (ATTD) of P was lower (P=0.03) in T2 as compared to CON and it was higher (P=0.02) in T3 as compared to T2. There were no differences in meat quality, relative organ weight, and cecum microbiota (P>0.05). The supplementation of PFA showed trends in improvement in ash content in the bone of birds fed T1, T2 and T4 diets compared with CON. Likewise, the supplementation of PFA tended to increase (P=0.07) Ca content in the bone of birds fed T1 diet compared to CON. In conclusion, dietary supplementation with 150 ppm PFA could improve BWG in birds fed protein reduced diet, improve apparent total tract digestibility (ATTD) of P, and the bone Ca contents in broilers.

Real-time seismic structural response prediction system based on support vector machine

  • Lin, Kuang Yi;Lin, Tzu Kang;Lin, Yo
    • Earthquakes and Structures
    • /
    • v.18 no.2
    • /
    • pp.163-170
    • /
    • 2020
  • Floor acceleration plays a major role in the seismic design of nonstructural components and equipment supported by structures. Large floor acceleration may cause structural damage to or even collapse of buildings. For precision instruments in high-tech factories, even small floor accelerations can cause considerable damage in this study. Six P-wave parameters, namely the peak measurement of acceleration, peak measurement of velocity, peak measurement of displacement, effective predominant period, integral of squared velocity, and cumulative absolute velocity, were estimated from the first 3 s of a vertical ground acceleration time history. Subsequently, a new predictive algorithm was developed, which utilizes the aforementioned parameters with the floor height and fundamental period of the structure as the new inputs of a support vector regression model. Representative earthquakes, which were recorded by the Structure Strong Earthquake Monitoring System of the Central Weather Bureau in Taiwan from 1992 to 2016, were used to construct the support vector regression model for predicting the peak floor acceleration (PFA) of each floor. The results indicated that the accuracy of the predicted PFA, which was defined as a PFA within a one-level difference from the measured PFA on Taiwan's seismic intensity scale, was 96.96%. The proposed system can be integrated into the existing earthquake early warning system to provide complete protection to life and the economy.

A Study on the Stress Simulation for the Body Design of a PFA-lined Plug Valve (PFA 라이닝 플러그 밸브 설계를 위한 밸브 본체의 응력 시뮬레이션)

  • Kang, Shin-Han
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.10 no.3
    • /
    • pp.500-506
    • /
    • 2009
  • This study, is aimed to support the valve design engineer by a CAE simulation on the body of a PFA-lined plug valve, and focuses on static stress analysis, location of the weak point on bending and stiffness of the valve body. To determine whether the valve body can resist being transformed by loads, 1 simulated the stress distribution using CAD/CAE softwares. The 'step' file converted by CAD software after solid modeling is imported to the CAE software. Through simulation procedure, it is shown that the designed-solid-model fur a valve body has stiffness on bending and torsion but has weakness for side bending moment. Also, it is expected that the valve design engineer will understand the basic process of CAE and will be able to apply on his task.

Study on the Closure Time in Healthy Small-Breed Dogs by Platelet Function Analyzer-200

  • Kyoungyoun Lee;Yoonhee Kim;Ulsoo Choi
    • Journal of Veterinary Clinics
    • /
    • v.40 no.5
    • /
    • pp.330-335
    • /
    • 2023
  • Platelet function evaluation by PFA-100 or -200 has been known to be objective and sensitive for assessing platelet function and dysfunction of Von Willebrand Factor in humans and dogs. However, using the C/EPI cartridge in dogs is controversial. This study aimed to establish a reference range for PFA closure time in healthy small breed dogs (body weight < 10 kg) and to evaluate the effectiveness of both C/ADP and C/EPI cartridges for these dogs. Citrated blood samples were collected from 50 clinically healthy small breed dogs that were admitted for presurgical procedures or health checkups, and closure times were measured using the PFA-200. Reference ranges were determined as 42-144 s (median 67 s, mean 71.2 s, SD ± 21.2 s, 95% RI 43-140 s) , for CT-C/ADP and 41-200 s (median 87, mean 91.2 s, SD ± 31.8 s, 95% RI 44-195 s) for CT-C/EPI. The present study demonstrated that the reference ranges for PFA closure times in small breed dogs are in line with existing reference ranges. The utilization of C/ADP cartridges is the preferred choice for evaluating platelet function in small breed dogs. However, due to variable responses of epinephrine to platelet aggregation in dogs, caution should be exercised when using C/EPI cartridges.

Effect of Diets Containing Ground Charcoal Powder, Wood Vinegar and Fermented Acetic Acid on the Protein and Energy Metabolism in White Leghorn Strain Layer (백색 산란계의 단백질 및 에너지 대사에 미치는 성형 목탄가루, 목초액 및 양조식초 첨가사료의 영향)

  • 고태송;최윤석;김동희
    • Korean Journal of Poultry Science
    • /
    • v.18 no.2
    • /
    • pp.85-95
    • /
    • 1991
  • The investigation concerned an effect of the ground charcoal powder and organic acids on the digestibilities of protein and energy or the contents of uric acid, ammonia, creatine and urea in excreta of 113 week-old White Leghorn strain layers. Birds were fed basal (control) diet composed of mainly corn-soybean meal during a week of previous feeding and subsequent experimental diets during 12 weeks of experimental feeding . The experimental diets were the control diet(CON). diet(CPD) substituted 0.5% of the ground charcoal powder with the defatted rice bran of the CON, diet(PWV) added 0.1mM(based on the acetic acid) wood vinegar in the CPD and diet(PFA) added 0.1mM (based on the acetic acid) fermented acetic acid in the CPD. Birds fed CPD excreted significantly(P<0.05) more fecal nitrogen(FN) and lower urinary nitrogen (UN) than those of birds fed CON. Digestibility of protein was lower significantly (P< 0.05) in CPB-fed bird than in bird fed CON. while birds fed CON. PWV and PFA showed similar values. Also urinary nitrogen per nitrogen intake (UN/NI) or absorbed nitrogen (UN/AN) was significantly (P<0.05) lower in birds fed CPD compared with those in birds fed CON. And birds fed PWV tended to increase UN/NI and UN/AN, while PFA-fed birds excreted significantly (P<0.05) higher UN/Nl and UN/Ah than those of birds fed CPD diet. The uric acid nitrogen (UAN) per nitrogen intake (UAN/NI) or absorbed nitrogen (UAN/AN) were lower significantly(P<0.05) in CPD-fed birds and were tended to decrease in birds fed PWV compared with those in birds fed CON and PFA The ammoniacal nitrogen(AMN) per nitrogen intake (AMN/NI) or absorbed nitrogen (AMN/NI) was tended to increase in birds fed experimental diets and was increased significantly(P<0.05) in birds fed PFA compared with those of birds fed CON. The excretion of creatine and urea nitrogen per nitrogen intake or absorbed nitrogen was shown similar values among birds fed experimental diets Digestibility of energy (DE/GE) was not shown any significant effect of experimental diet and were in the range of 80~84%. But metabolizability (ME/GE or MEn/GE) was increased in birds fed CPD and PWV and was decreased in birds fed PFA compared with those in birds fed CON. Although birds fed PWV showed significantly(P<0.05) higher ME/GE than bird fed PFA, the MEn/GE were higher significantly (P<0.05) in birds fed CON and CPD compared with that in birds fed PFA. Fecal energy affects 10~23% in the change of metabolizability though significant effect of fecal energy on the metabolizability were not found. But the effect of urinary energy on the metabolizability of diet was lowered as 2.3~3, 0% and the effect of experimental diets on the metabolizability of diets was due to change of urinary energy which also was originated from the change of uric acid energy.

  • PDF

- Development of Design Support Methodology Using Product Function Analysis - (제품기능분석을 이용한 설계지원 방법론 개발)

  • 김형준;이내형;서광규
    • Journal of the Korea Safety Management & Science
    • /
    • v.5 no.2
    • /
    • pp.111-127
    • /
    • 2003
  • In this paper, a new method of product function analysis is presented to categorize various design information generated in product development processes. In order to improve product functions, designers must understand unit functions and modified parts of products. The product function analysis (PFA) is based on the designer's understanding of product functions. The proposed PFA provides the methodology to classify the various functions systematically and understand the relation between functions easily. Using this approach, efficient design support system can be developed and used for designers to support decision-making with design knowledge.

Power Flow Analysis of Vibration of a Plate Covered with a Damping Sheet (제진 평판 진동에 대한 파워흐름해석)

  • Lee, Jin-Young;Kil, Hyun-Gwon;Song, Jee-Hun;Hong, Suk-Yoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.19 no.5
    • /
    • pp.530-536
    • /
    • 2009
  • In this paper, the power flow analysis(PFA) has been used to analyze the vibration of a plate covered with a damping sheet. Experiments have been performed to measure the loss factor and frequency response functions of the plate covered with the damping sheet. The data for the loss factor has been used as the input data to predict the vibration of the coupled plates with PFA. The comparison between the experimental results and the predicted PFA results for the frequency response functions has been performed. It showed that PFA can be effectively used to predict structural vibration of a plate covered with a damping sheet in medium-to-high frequency range.