• Title/Summary/Keyword: false negative

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Identification of Staphylococcus hyicus subsp hyicus of swine and poultry origin by API STAPH-IDENT system (API STAPH-IDENT system에 의한 돼지 및 닭유래(由來) staphylococcus hyicus subsp hyicus의 동정(同定))

  • Park, Cheong-kyu
    • Korean Journal of Veterinary Research
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    • v.34 no.2
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    • pp.315-320
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    • 1994
  • The API STAPH-IDENT system was evaluated as a means for identifying Staphylococcus hyicus subsp hyicus straints isolated from swine and poultry. Of 80 strains from swine, 68 (85%) were correctly identified by the API STAPH-IDENT system alone after 5 h of incubation. When results were determined after 24 h of incubation, the accuracy of this system alone was 93.8%. By additional tests in conjunction with the API STAPH-IDENT system, however, all 80 strains could be correctly identified. Of 120 strains from poultry, 87 (72.5%) required additional testing to achieve a correct identification, and 33 (27.5%) were incorrectly identified by this system after 5 h of incubation. After 24 h of incubation, 99 of 120 (82.5%) avian strains were incorrectly identified as Staph epidermidis owing to false-negative mannose and trehalose utilizations. Seventy-seven (96.3%) of swine strains were positive for ${\beta}-glucuronidase$, whereas all 120 strains recovered tram poultry were negative for it.

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Forensic Image Classification using Data Mining Decision Tree (데이터 마이닝 결정나무를 이용한 포렌식 영상의 분류)

  • RHEE, Kang Hyeon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.7
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    • pp.49-55
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    • 2016
  • In digital forensic images, there is a serious problem that is distributed with various image types. For the problem solution, this paper proposes a classification algorithm of the forensic image types. The proposed algorithm extracts the 21-dim. feature vector with the contrast and energy from GLCM (Gray Level Co-occurrence Matrix), and the entropy of each image type. The classification test of the forensic images is performed with an exhaustive combination of the image types. Through the experiments, TP (True Positive) and FN (False Negative) is detected respectively. While it is confirmed that performed class evaluation of the proposed algorithm is rated as 'Excellent(A)' because of the AUROC (Area Under Receiver Operating Characteristic Curve) is 0.9980 by the sensitivity and the 1-specificity. Also, the minimum average decision error is 0.1349. Also, at the minimum average decision error is 0.0179, the whole forensic image types which are involved then, our classification effectiveness is high.

Surgical Treatment of Cutaneous Angiosarcoma of Scalp:Usefulness of Preoperative Mapping Biopsies (두피에 발생한 혈관육종의 수술시 Mapping Biopsy의 유용성)

  • Kang, Min-Gu;Park, Jong-Lim;Kim, Myung-Good;Minn, Kyung-Won;Koh, Kyung-Suck;Chang, Hak
    • Korean Journal of Head & Neck Oncology
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    • v.23 no.1
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    • pp.37-40
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    • 2007
  • Objectives:Cutaneous angiosarcoma is an infrequent but aggressive neoplasm involving the skin of the face and scalp. Unfamiliarity with the clinical manifestations of cutaneous angiosarcoma frequently leads to misdiagnosis and delay in treatment. Complete surgical resection requires the performance of preoperative staging biopsies to determine the true extent of the neoplasm. Intraoperative frozen section analysis to determine the adequacy of the surgical resection is unreliable due to the high false negative rate. Material and Methods:In five scalp angiosarcoma cases, mapping biopsies were performed at far from the suspected edge of the neoplasm. On permanent pathology, we obtained tumor free margin with occasional focal involvement of the tumor. Results:Frozen-section analysis of the resected margins is inconclusive, for the subtle diagnostic features of angiosarcoma are distorted by the tissue processing required for frozen-section analysis. The characteristic dermal vessels lined by their malignant cells are collapsed by the freezing process. This results in a high rate of false-negative reports and possibly leads to incomplete resection of the neoplasm. Conclusion:Our recommendation is to establish the margins of the tumor by performing preoperative evaluations by mapping biopsies.

Intraoperative Monitoring of Motor-Evoked Potentials for Supratentorial Tumor Surgery

  • Lee, Jung Jae;Kim, Young Il;Hong, Jae Taek;Sung, Jae Hoon;Lee, Sang Won;Yang, Seung Ho
    • Journal of Korean Neurosurgical Society
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    • v.56 no.2
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    • pp.98-102
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    • 2014
  • Objective : The purpose of this study was to assess the feasibility and clinical efficacy of motor evoked potential (MEP) monitoring for supratentorial tumor surgery. Methods : Between 2010 and 2012, to prevent postoperative motor deterioration, MEP recording after transcranial stimulation was performed in 84 patients with supratentorial brain tumors (45 males, 39 females; age range, 24-80 years; median age, 58 years). MEP monitoring results were correlated with postoperative motor outcome compared to preoperative motor status. Results : MEP recordings were stable in amplitude (<50% reduction in amplitude) during surgery in 77 patients (91.7%). No postoperative motor deficit was found in 66 out of 77 patients with stable MEP amplitudes. However, postoperative paresis developed in 11 patients. False negative findings were associated with edema in peri-resectional regions and postoperative bleeding in the tumor bed. MEP decrease in amplitude (>50%) occurred in seven patients (8.3%). However, no deficit occurred postoperatively in four patients following preventive management during the operation. Three patients had permanent paresis, which could have been associated with vascular injury during tumor resection. Conclusions : MEP monitoring during supratentorial tumor surgery is feasible and safe. However, false negative MEP results associated with postoperative events may occur in some patients. To achieve successful monitoring, collaboration between surgeon, anesthesiologist and an experienced technician is mandatory.

Effectiveness of Transbronchial Fine Needle Aspiration in Diagnosing Lung Cancers (폐종양의 세포학적 진단에서 경기관지세침흡인검사의 유용성)

  • Kim, Tae-Yub;Gong, Gyung-Yub;Kim, Won-Dong;Kim, On-Ja
    • The Korean Journal of Cytopathology
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    • v.8 no.2
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    • pp.109-114
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    • 1997
  • Transbronchial fine needle aspiration(TBNA) is one of the cytologic methods in diagnosing lung cancers. TBNA can be used in cases of hilar, mediastinal or lung masses adjacent to the bronchi. We analyzed and compaired the findings of 27 cases of TBNA and bronchial washing and brushing(BW/BB) in lung cancers confirmed by either biopsy or surgical resection between Jun, 1996 and May, 1997 in Asan Medical Center. They were 18 cases of non-small cell carcinomas(eight squamous cell carcinomas, nine adenocarcinomas, and one large cell undifferentiated carcinoma), eight cases of small cell carcinomas, and one case of metastatic hepatocellular carcinoma. The sensitivity of TBNA was 37%(10/27) and false negative was 63%(17/27). Although the sensitivity of BW/BB w3s 56%(15/27), it was not different statistically from that of TBNA(Chi square, p=0.38). Overall sensitivity of TBNA and BW/BB in this series was 70%(19/27). Forty-seven percent of false negative TBNA(8/17) were positive in BW/BB. The findings suggest that the addition of TBNA to the standard BW/BB increases diagnostic yield in cytologic diagnosis of lung cancer.

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Spectrum of Cytological Findings in Fine Needle Aspiration Cytology of Breast Lumps with Histopathology Correlation: Experience in a Tertiary Care Rural Hospital in India

  • Kochhar, Ajay Kumar;Jindal, Umesh;Singh, Karandeep
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7257-7260
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    • 2013
  • To determine the pattern of disease in patients presenting with breast lumps and to determine the sensitivity and specificity of fine needle aspiration cytology of benign and malignant diseases as a diagnostic tool by correlating with histopathology findings. This retrospective study was carried out in the Department of Pathology, Maharaja Agrasen Medical College, Agroha, from Jan 2008 to April 2012. Fine needle aspiration cytology was performed on 370 cases and out of these 52 cases were received in the Department for histopathological examination. Fibroadenoma was the most common disease encountered, in 88 (24%), with a peak incidence in second and third decade of life. Fibrocystic disease was second, being common in the third and fourth decades of life. Peak incidences of duct ectasia, granulomatous and tubercular mastitis were seen in the third decade. Gynaecomastia showed two peak incidences in second and sixth decades of life. Out of total 370 cases undergoing fine needle aspiration, benign cases were 316 (85.4%), malignant and suspicious were 54 (14.6%) and 10 (2.70%) respectively. Out of total 22 histological confirmed malignant lesions 19 were interpreted as malignant cytologically while two as suspicious and one as benign. All thirty histologically confirmed benign cases were diagnosed as benign cytologically. The sensitivity, specificity, positive and negative predictive values were 98%, 100%, 100% and 96.4% respectively. FNA cytology is highly accurate for diagnosis of breast masses. However, the clinician should correlate FNA cytological results with physical examination and imaging findings to prevent false negative and false positive events and to obtain optimal management of their patients.

A Method for Quantifying the Risk of Network Port Scan (네트워크 포트스캔의 위험에 대한 정량화 방법)

  • Park, Seongchul;Kim, Juntae
    • Journal of the Korea Society for Simulation
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    • v.21 no.4
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    • pp.91-102
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    • 2012
  • Network port scan attack is the method for finding ports opening in a local network. Most existing IDSs(intrusion detection system) record the number of packets sent to a system per unit time. If port scan count from a source IP address is higher than certain threshold, it is regarded as a port scan attack. The degree of risk about source IP address performing network port scan attack depends on attack count recorded by IDS. However, the measurement of risk based on the attack count may reduce port scan detection rates due to the increased false negative for slow port scan. This paper proposes a method of summarizing 4 types of information to differentiate network port scan attack more precisely and comprehensively. To integrate the riskiness, we present a risk index that quantifies the risk of port scan attack by using PCA. The proposed detection method using risk index shows superior performance than Snort for the detection of network port scan.

Electrical Detection of Ear Acupuncture Points and Musculoskeletal Pain (경혈탐측기에 반응한 이혈(耳穴)과 신체 동통 부위와의 관계 연구)

  • Kang, Mun-Su;Park, Hyun-Chul;Kim, Lak-Hyung;Yu, Jeong-Suk;Song, Beom-Yong
    • Journal of Acupuncture Research
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    • v.24 no.6
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    • pp.187-193
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    • 2007
  • Objectives : The objectives of this study were to investigate the relationship between electrical detection of ear acupuncture points and musculoskeletal pain. Methods : 18 adults who have musculoskeletal pain without trauma factorsparticipated in this study. They answered the questionnaire and their ear acupuncture points were examined with electrical detectors. We analyzed the relationship between electrical detection of ear acupuncture points and musculoskeletal pain with concordance rate and validity. Results : Total concordance rates of the head region was 68.00%(questionnaire) 32.08%(investigation), that of vertebral region was 67.86%, 59.38%, that of both upper limbs was 86.67%, 39.69%, and that of both lower limbs was 50.00%, 23.46%. The true positive rate was 0.704, the true negative rate was 0.492, the false positive rate was 0.508, and the false negative rate was 0.296 in the validity test. In the head, two concordance rates of the temporal and occipital regions were relatively higher than those of the parietal and frontal regions. In the vertebral region, two concordance rates of the cervical and lumbar regions were relatively higher than those of the thoracic and sacrum regions. In the upper limb, two concordance rates of the shoulder and shoulder joints were relatively higher than those of the others. In the lower limb, concordance rates of investigation were relatively low at all areas. The right lower limb was relatively higher than the left in concordance rates of the questionnaire. Conclusions : The results suggest that electrical detection of ear acupuncture points can be used in the diagnosis and treatment of musculoskeletal pain.

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Median Filtering Detection using Latent Growth Modeling (잠재성장모델링을 이용한 미디언 필터링 검출)

  • Rhee, Kang Hyeon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.1
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    • pp.61-68
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    • 2015
  • In recent times, the median filtering (MF) detector as a forensic tool for the recovery of forgery images' processing history has concerned broad interest. For the classification of MF image, MF detector should be designed with smaller feature set and higher detection ratio. This paper presents a novel method for the detection of MF in altered images. It is transformed from BMP to several kinds of MF image by the median window size. The difference distribution values are computed according to the window sizes and then the values construct the feature set same as the MF window size. For the MF detector, the feature set transformed to the model specification which is computed using latent growth modeling (LGM). Through experiments, the test image is classified by the discriminant into two classes: the true positive (TP) and the false negative (FN). It confirms that the proposed algorithm is to be outstanding performance when the minimum distance average is 0.119 in the confusion of TP and FN for the effectivity of classification.

Proposition of balanced comparative confidence considering all available diagnostic tools (모든 가능한 진단도구를 활용한 균형비교신뢰도의 제안)

  • Park, Hee Chang
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.3
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    • pp.611-618
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    • 2015
  • By Wikipedia, big data is a broad term for data sets so large or complex that traditional data processing applications are inadequate. Data mining is the computational process of discovering patterns in huge data sets involving methods at the intersection of association rule, decision tree, clustering, artificial intelligence, machine learning. Association rule is a well researched method for discovering interesting relationships between itemsets in huge databases and has been applied in various fields. There are positive, negative, and inverse association rules according to the direction of association. If you want to set the evaluation criteria of association rule, it may be desirable to consider three types of association rules at the same time. To this end, we proposed a balanced comparative confidence considering sensitivity, specificity, false positive, and false negative, checked the conditions for association threshold by Piatetsky-Shapiro, and compared it with comparative confidence and inversely comparative confidence through a few experiments.