• Title/Summary/Keyword: Primary frequency

Search Result 1,524, Processing Time 0.024 seconds

Cytologic Features and Distribution of Primary Sites of Malignant Cells in Cerebrospinal Fluid - Analysis of 1,438 Specimeus - (뇌척수액내 종양세포의 원발부위 분석 및 세포학적 특징 - 총 1,438예 분석 -)

  • Kim, Yeon-Mee;Jeon, Mi-Yeong;Chi, Je-Geun
    • The Korean Journal of Cytopathology
    • /
    • v.11 no.2
    • /
    • pp.65-73
    • /
    • 2000
  • Cytologlc evaluation of cerebrospinal fluid(CSF) is an effective mean for diagnosing many disorders involving the central nervous systems(CNS). One of the most important reasons for cytologic examination of CSF is to detect metastatic or primary neoplasms of the CNS. We did a retrospective study of 1,438 CSF specimens obtained between 1992 and 1996. A total of 1,205 adult and 233 pediatric CSF specimens from 947 patients were accessed at the Department of Pathology of Seoul National University Hospital and Children's Hospital, respectively. Among 1,438 CSF cytology specimens, 169 cases(11.8%, 77 patients) including 135 adult cases(59 patients) and 34 pediatric cases(18 patients) were positive for malignant cells. Diagnoses included 50 metastatic carcinomas(adult, 60; pediatric, 0); 46 malignant lymphomas(adult, 44; pediatric, 2); 21 leukemias(adult, 20; pediatric, 1); 4 retinoblastomas(adult, 0; pediatric 4); 2 rhabdomyosarcomas(adult, 0; pediatric, 2); 1 multiple myeloma(adult, 1; pediatric, 0), and 35 primary CNS neoplasms(adult, 10; pediatric, 25). The most commonly identified metastatic carcinomas in adults were adenocarcinoma. Their primary sites were the lung, gastrointestinal tract, and breast in order of frequency. The most common primary CNS neoplasm in children was medulloblastoma.

  • PDF

Design of a High-Precision Constant Current AC-DC Converter with Inductance Compensation

  • Chang, Changyuan;Xu, Yang;Bian, Bin;Chen, Yao;Hu, Junjie
    • Journal of Power Electronics
    • /
    • v.16 no.3
    • /
    • pp.840-848
    • /
    • 2016
  • A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

A Novel IPT System Based on Dual Coupled Primary Tracks for High Power Applications

  • Li, Yong;Mai, Ruikun;Lu, Liwen;He, Zhengyou
    • Journal of Power Electronics
    • /
    • v.16 no.1
    • /
    • pp.111-120
    • /
    • 2016
  • Generally, a single phase H-bridge converter feeding a single primary track is employed in conventional inductive power transfer systems. However, these systems may not be suitable for some high power applications due to the constraints of the semiconductor switches and the cost. To resolve this problem, a novel dual coupled primary tracks IPT system consisting of two high frequency resonant inverters feeding the tracks is presented in this paper. The primary tracks are wound around an E-shape ferrite core in parallel which enhances the magnetic flux around the tracks. The mutual inductance of the coupled tracks is utilized to achieve adjustable power sharing between the inverters by configuring the additional resonant capacitors. The total transfer power can be continuously regulated by altering the pulse width of the inverters' output voltage with the phase shift control approach. In addition, the system's efficiency and the control strategy are provided to analyze the characteristic of the proposed IPT system. An experimental setup with total power of 1.4kW is employed to verify the proposed system under power ratios of 1:1 and 1:2 with a transfer efficiency up to 88.7%. The results verify the performance of the proposed system.

Level of Knowledge and Utilization of Fortified Maize Flour by Primary Food Shoppers in Mathare, Nairobi County, Kenya

  • SAMIRA, Hussein;NJOGU, Eunice;MAKWORO, Drusilla
    • The Korean Journal of Food & Health Convergence
    • /
    • v.6 no.2
    • /
    • pp.1-8
    • /
    • 2020
  • Micronutrient malnutrition severely affects development and functioning of the body leading to increased morbidity and mortality. The study adopted a cross-sectional research design; cluster sampling was used to target 318 households. The significance level was P < 0.05, the mean age of primary food shoppers was 33 years and the average income was 3,000-5,000 Kenya shillings. Slightly above half, 55% of the primary food shoppers knew about fortification but only 25% understood its meaning. Fortified maize flour was consumed by < 80% of primary food shoppers however utilization frequency was low. In conclusion factors that were significantly associated with utilization of fortified maize flour included; knowledge on fortified maize flour (p=0.00), household size (p=0.005), preference of fortified maize flour (p=0.000) and level of fortification knowledge (p=0.002). Availability and price were ranked as the most important factors that influence utilization of fortified maize flour at 58% and 55% contrary nutritional value was ranked least important at 37%. The ministry of health and concerned millers should make more emphasis on creating and sustaining awareness more so a steady supply and affordable prices should be ensured by millers so that more primary food shoppers can be able to utilize the fortified maize flour.

Whole-exome sequencing analysis in a case of primary congenital glaucoma due to the partial uniparental isodisomy

  • Zavarzadeh, Parisima Ghaffarian;Bonyadi, Morteza;Abedi, Zahra
    • Genomics & Informatics
    • /
    • v.20 no.3
    • /
    • pp.28.1-28.7
    • /
    • 2022
  • We described a clinical, laboratory, and genetic presentation of a pathogenic variant of the CYP1B1 gene through a report of a case of primary congenital glaucoma and a trio analysis of this candidate variant in the family with the Sanger sequencing method and eventually completed our study with the secondary/incidental findings. This study reports a rare case of primary congenital glaucoma, an 8-year-old female child with a negative family history of glaucoma and uncontrolled intraocular pressure. This case's whole-exome sequencing data analysis presents a homozygous pathogenic single nucleotide variant in the CYP1B1 gene (NM_000104:exon3:c.G1103A:p.R368H). At the same time, this pathogenic variant was obtained as a heterozygous state in her unaffected father but not her mother. The diagnosis was made based on molecular findings of whole-exome sequencing data analysis. Therefore, the clinical reports and bioinformatics findings supported the relation between the candidate pathogenic variant and the disease. However, it should not be forgotten that primary congenital glaucoma is not peculiar to the CYP1B1 gene. Since the chance of developing autosomal recessive disorders with low allele frequency and unrelated parents is extraordinary in offspring. However, further data analysis of whole-exome sequencing and Sanger sequencing method were applied to obtain the type of mutation and how it was carried to the offspring.

Effects of Education Status to Respond to COVID-19 and Work Fatigue of Primary Health Care Practitioners (보건진료 전담공무원의 코로나 19 대응을 위한 교육 현황 및 업무피로도에 미치는 영향)

  • Yim, Eun Shil;Seo, In Ju;Kim, Soon Gu
    • Journal of Korean Academy of Rural Health Nursing
    • /
    • v.18 no.1
    • /
    • pp.40-48
    • /
    • 2023
  • Purpose: This study is a descriptive research that analyzes the current status of education for COVID-19 response tasks and factors affecting work fatigue of primary health care practitioners who have experience in dispatching to respond to COVID-19. Methods: This study collected data through an online survey from September 21 to 29, 2022, targeting 193 primary health care practitioners. The data were analyzed by frequency, percentage, mean, standard deviation, and logistic regression analysis using the SPSS 25.0 program. Results: 74.1% of the study subjects were dispatched without receiving disaster medical training to respond to COVID-19. 59.6% of the study subjects' work fatigue was above the level of being very tired. The factors that affect the work fatigue of the subjects were disaster participation experience, work intensity, compensation regulations, compensation satisfaction, and understanding of COVID-19 guidelines. Conclusion: Based on the results of this study, an educational program for systematic disaster response and preparation for primary health care practitioners in charge of public health care should be developed to efficiently cope with the occurrence of new infectious diseases in the future.

Spacing and crowding of the primary dentition in Korean children - relationship to tooth sizes and dental arch dimension (한국인 아동의 유치열기의 특성 - 치아 치열궁의 관계)

  • Im, Dong-Hyuk;Kim, Tae-Woo;Nahm, Dong-Seok;Chang, Young-Il
    • The korean journal of orthodontics
    • /
    • v.36 no.1 s.114
    • /
    • pp.84-90
    • /
    • 2006
  • The aims of this study were to investigate the prevalence of spaced, closed, and crowded primary dentitions by sex and arch in Korean children from Kanghwa, and to determine the frequency of the primate and developmental spaces. The differences in the mesiodistal crown diameters and the arch dimensions between the spaced, closed, and crowded primary dentitions were also evaluated. Dental casts of 102 preschool children (57 males and 45 females, aged $4{\sim}5$ years) were studied. The prevalence of spacing in the primary dentition was 63.2% In males and 57.8% in females. The frequency of spacing was greater in males than in females, and greater in the maxillary arch than in the mandibular arch. The crowns were significantly larger and the arches significantly narrower in closed and crowded dentitions than in those with spacing (p<0.05). The results showed that the prevalence of spacing was lower than that found in previous studies and the presence of spacing in the anterior region was related to the mesiodistal crown diameter and the intercanine width.

The Relationship between the Characteristics of Social Support and Post-Stroke Depression (사회적 지지의 특성에 따른 뇌졸중 환자의 우울)

  • Kim, In-Ja;Suh, Moon-Ja;Kim, Keum-Soon;Cho, Nam-Ok
    • The Korean Journal of Rehabilitation Nursing
    • /
    • v.2 no.2
    • /
    • pp.206-214
    • /
    • 1999
  • The effect s of social support on post-stroke depression were investigated. Social support was classified into three categories : primary caregiver's, significant other's, and professional support. And primary caregiver's and significant other's support were divided into their relation, living state (which means they living together or not), frequency which they met at, and perceived satisfaction about the support, respectively. Professional support was divided into number of professionals who take care of, frequency they met at, and perceived satisfaction. The subjects were 254 stroke patients who had been discharged and were taken follow-up care at the out patient department. The depression was measured using CES-D. Out of the primary caregiver's support, only relation and perceived satisfaction were identified to affect the post-stroke depression. The patients who primarily their spouse takes care of were less depressed than those who their adult children take care of. None of the significant other's support affects the post-stroke depression. Only perceived satisfaction of the professional support was found to affect the post-stroke depression. So it was found that the quality, not the amount, of care was important to post-stroke depression. These results also support the claim that the facilities and teaching programs for primary caregivers are necessary.

  • PDF

Cluster-head Decision Method for Cognitive Radio Based on Wireless Ad-hoc Network (인지 무선 기반 애드 혹 네트워크에서의 클러스터 헤드 선정기법)

  • Lee, Kyung-Sun;Kim, Yoon-Hyun;Kim, Jin-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.12 no.1
    • /
    • pp.91-96
    • /
    • 2012
  • Ad-hoc networks can be used various environment, which it is difficult to construct infrastructures, such as shadowing areas, disaster areas, war area, and so on. In order to support to considerable and various wireless services, more spectrum resources are needed. However, efficient utilization of the frequency resource is difficult because of spectrum scarcity and the conventional frequency regulation. Ad-hoc networks employing cognitive radio (CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. In CR based wireless ad-hoc networks, cluster-head decides the existence of primary user using sensing information of primary user from each ad-hoc device. However, it is still defective research to decide cluster head among the a lot of ad-hoc devices. So, in this paper, we show the decision method of cluster head in CR based wireless and detection probabilities of primary user based on decision method of cluster head.

RESONANCE FREQUENCY ANALYSIS IN NON-SUBMERGED, INTERNAL TYPE IMPLANT WITH SINUS AUGMENTATION USING DEPROTEINIZED BOVINE BONE MINERAL (이종골을 이용한 상악동 측벽거상술과 동시 식립한 임프란트에서 안정성에 대한 공진 주파수 분석)

  • Lee, Ju-Hyon;Min, Hyun-Gi;Lee, Jin-Sook;Kim, Myung-Rae;Kang, Na-Ra
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.30 no.6
    • /
    • pp.554-560
    • /
    • 2008
  • In posterior maxilla, it is difficult to achieve primary stability of implants due to sinus pneumatization, alveolar bone loss, and low bone quality. The accurate and objective primary stability assessment is important for good prognosis of implants. Purpose: The aim of this study was to assess the primary stability of the non-submerged, internal type implants with maxillary sinus augmentation using deproteinized bovine bone mineral by a resonance frequency analyzer, when residual alveolar bone height is under 8mm Materials and methods: A total of 20 implants was placed into 5 grafted maxillary sinuses in 5 patients. Deproteinized bovine bone mineral (Bio-$Oss^{(R)}$) was used as graft material. SS II implants (diameter 4.1mm, and length 11.5mm, SLA suface)) were placed. All of the patients received maxillary sinus graft procedure by 1-step technique. Residual bone height was $1.3{\sim}7.8mm$ (mean 4.4mm) measured by panorama radiography. After implant placement, RFA was measured at 4,8,12,20 weeks. The results were divided into 2 groups; RFA value under 4mm and over 5mm of bone height. It was statistically analyzed. Results: 1. The primary stability of implants was increased with time 2. The RFA value was above 65 ISQ at 12 weeks 3. There was no correlation between RFA and residual alveolar bone height in maxillary sinus augmentation by 1-step technique. Conclusion: 1-step surgical procedure is a feasible option for patients with as little as 4mm residual alveolar bone height, when utilizing non-submerged, internal type implants with xenografts.