• Korean Journal of Radiology
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• 제22권1호
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• pp.131-138
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• 2021

Objective: Iterative reconstruction degrades image quality. Thus, further advances in image reconstruction are necessary to overcome some limitations of this technique in low-dose computed tomography (LDCT) scan of the chest. Deep-learning image reconstruction (DLIR) is a new method used to reduce dose while maintaining image quality. The purposes of this study was to evaluate image quality and noise of LDCT scan images reconstructed with DLIR and compare with those of images reconstructed with the adaptive statistical iterative reconstruction-Veo at a level of 30% (ASiR-V 30%). Materials and Methods: This retrospective study included 58 patients who underwent LDCT scan for lung cancer screening. Datasets were reconstructed with ASiR-V 30% and DLIR at medium and high levels (DLIR-M and DLIR-H, respectively). The objective image signal and noise, which represented mean attenuation value and standard deviation in Hounsfield units for the lungs, mediastinum, liver, and background air, and subjective image contrast, image noise, and conspicuity of structures were evaluated. The differences between CT scan images subjected to ASiR-V 30%, DLIR-M, and DLIR-H were evaluated. Results: Based on the objective analysis, the image signals did not significantly differ among ASiR-V 30%, DLIR-M, and DLIR-H (p = 0.949, 0.737, 0.366, and 0.358 in the lungs, mediastinum, liver, and background air, respectively). However, the noise was significantly lower in DLIR-M and DLIR-H than in ASiR-V 30% (all p < 0.001). DLIR had higher signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) than ASiR-V 30% (p = 0.027, < 0.001, and < 0.001 in the SNR of the lungs, mediastinum, and liver, respectively; all p < 0.001 in the CNR). According to the subjective analysis, DLIR had higher image contrast and lower image noise than ASiR-V 30% (all p < 0.001). DLIR was superior to ASiR-V 30% in identifying the pulmonary arteries and veins, trachea and bronchi, lymph nodes, and pleura and pericardium (all p < 0.001). Conclusion: DLIR significantly reduced the image noise in chest LDCT scan images compared with ASiR-V 30% while maintaining superior image quality.

• Korean Journal of Radiology
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• 제22권2호
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• pp.263-280
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• 2021

Percutaneous transthoracic needle biopsy (PTNB) is one of the essential diagnostic procedures for pulmonary lesions. Its role is increasing in the era of CT screening for lung cancer and precision medicine. The Korean Society of Thoracic Radiology developed the first evidence-based clinical guideline for PTNB in Korea by adapting pre-existing guidelines. The guideline provides 39 recommendations for the following four main domains of 12 key questions: the indications for PTNB, pre-procedural evaluation, procedural technique of PTNB and its accuracy, and management of post-biopsy complications. We hope that these recommendations can improve the diagnostic accuracy and safety of PTNB in clinical practice and promote standardization of the procedure nationwide.

• 산업융합연구
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• 제22권7호
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• pp.1-13
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• 2024

전자정부 서비스 중 지능형 CCTV 관제 플랫폼은 인공지능을 활용하여 사람, 자동차 등 주요 객체가 CCTV상에 나타났을 경우, 관제요원에게 표출해 주는 선별 관제 서비스이다. 지능형 CCTV 관제 플랫폼을 운영할 경우 비상 상황 발생 시 신속한 대처가 가능하고 민원 해결 증가로 시민들의 삶의 질 제고가 가능할 것으로 기대를 모으고 있다. 이에 본 연구는 비(非)시장재화인 지능형 CCTV 관제 플랫폼의 편익을 선택실험기법인 조건부가치측정법(CVM)을 적용하여 가구당 평균 지불의사액을 추정하고, 이를 토대로 사회적 편익을 계산하였다. 분석 결과 가구의 평균 지불의사액은 연간 6,908원, 국가 전체의 경제적 편익은 연간 약 1,504억 원으로 추정되었다. 본 연구는 그간 환경·공공재의 적용되던 CVM의 적용 범위를 지능형 전자정부 서비스 분야로 확장한 점에서 학술적 의의가 있다. 나아가, 지능형 CCTV 관제 플랫폼 도입이 활발하게 논의되는 현 상황에서, 이에 대한 편익을 화폐가치로 추정하였다는 점에서 실무적 시사점을 지닌다.

• 대한간호학회지
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• 제13권1호
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• pp.7-21
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• 1983

For the flexible and rational distribution of limited existing health resources based on measurements of individual risk, the socalled Risk Approach is being proposed by the World Health Organization as a managerial tool in maternal and child health care program. This approach, in principle, puts us under the necessity of developing a technique by which we will be able to measure the degree of risk or to discriminate the future outcomes of pregnancy on the basis of prior information obtainable at prenatal care delivery settings. Numerous recent studies have focussed on the identification of relevant risk factors as the Prior infer mation and on defining the adverse outcomes of pregnancy to be dicriminated, and also have tried on how to develope scoring system of risk factors for the quantitative assessment of the factors as the determinant of pregnancy outcomes. Once the scoring system is established the technique of classifying the patients into with normal and with adverse outcomes will be easily de veloped. The scoring system should be developed to meet the following four basic requirements. 1) Easy to construct 2) Easy to use 3) To be theoretically sound 4) To be valid In searching for a feasible methodology which will meet these requirements, the author has attempted to apply the“Likelihood Method”, one of the well known principles in statistical analysis, to develop such scoring system according to the process as follows. Step 1. Classify the patients into four groups: Group $A_1$: With adverse outcomes on fetal (neonatal) side only. Group $A_2$: With adverse outcomes on maternal side only. Group $A_3$: With adverse outcome on both maternal and fetal (neonatal) sides. Group B: With normal outcomes. Step 2. Construct the marginal tabulation on the distribution of risk factors for each group. Step 3. For the calculation of risk score, take logarithmic transformation of relative proport-ions of the distribution and round them off to integers. Step 4. Test the validity of the score chart. h total of 2, 282 maternity records registered during the period of January 1, 1982-December 31, 1982 at Ewha Womans University Hospital were used for this study and the“Questionnaire for Maternity Record for Prenatal and Intrapartum High Risk Screening”developed by the Korean Institute for Population and Health was used to rearrange the information on the records into an easy analytic form. The findings of the study are summarized as follows. 1) The risk score chart constructed on the basis of“Likelihood Method”ispresented in Table 4 in the main text. 2) From the analysis of the risk score chart it was observed that a total of 24 risk factors could be identified as having significant predicting power for the discrimination of pregnancy outcomes into four groups as defined above. They are: (1) age (2) marital status (3) age at first pregnancy (4) medical insurance (5) number of pregnancies (6) history of Cesarean sections (7). number of living child (8) history of premature infants (9) history of over weighted new born (10) history of congenital anomalies (11) history of multiple pregnancies (12) history of abnormal presentation (13) history of obstetric abnormalities (14) past illness (15) hemoglobin level (16) blood pressure (17) heart status (18) general appearance (19) edema status (20) result of abdominal examination (21) cervix status (22) pelvis status (23) chief complaints (24) Reasons for examination 3) The validity of the score chart turned out to be as follows: a) Sensitivity: Group $A_1$: 0.75 Group $A_2$: 0.78 Group $A_3$: 0.92 All combined : 0.85 b) Specificity : 0.68 4) The diagnosabilities of the“score chart”for a set of hypothetical prevalence of adverse outcomes were calculated as follows (the sensitivity“for all combined”was used). Hypothetidal Prevalence : 5％ 10％ 20％ 30％ 40％ 50％ 60％ Diagnosability : 12% 23% 40% 53% 64% 75% 80%.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권3호
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• pp.202-212
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• 2006

It is well-known that paclitaxel($Taxol^{(R)}$), which is extracted from the pacific and English yew, has been used as a chemotherapeutic agent for ovarian carcinoma and advanced breast carcinoma and Cyclosporin A, which is highly lipophilic cyclic peptide and isolated from a fungus, has been also used as an useful immunosuppressive drug after transplantation and is associated with cellular apoptosis. Since 1953, in which James Watson, Rosalind Franklin and Francis Crick discovered the double helical structure of DNA, a few kinds of techniques for identifying gene expression have been developed. In postgenomic period, many of researchers have used the DNA microarray which is high throughput screening technique to screen large numbers of gene expression simultaneously. In this study, we searched and screened the gene expression in the oral squamous cell carcinoma cell lines treated with $Taxol^{(R)}$, cyclosporin or cyclosporin combined with $Taxol^{(R)}$ using cDNA microarray. The results were as following; 1. It was useful that the appropriate concentration of Cyclosporin A and $Taxol^{(R)}$ used in oral squamous cell carcinoma cell line was under 1${\mu}g/ml$ and 3${\mu}g/ml$. 2. In the experimental group in which $Taxol^{(R)}$ and $Taxol^{(R)}$ + Cyclosporin A were used, the cell growth was extremely decreased. 3. In the group in which Cyclosporin A was used, the MTT assay was rarely decreased which means the activity of succinyl dehydrogenase is remained in mitochondria but in the group in which the mixture of Cyclosporin A and $Taxol^{(R)}$ were used, the MTT assay was extremely decreased. 4. In the each group in which Cyclosporin A(3 ${\mu}g/ml$) and $Taxol^{(R)}$(1 ${\mu}g/ml$) were used, the cell arrest was appeared in $G_2/M$ phase and in the group in which $Taxol^{(R)}$(3 ${\mu}g/ml$) was used, the cell arrest was appeared in both S phase and $G_2/M$ phase. 5. In the oral squamous cell carcinoma cell line treated with $Taxol^{(R)}$, several genes including ANGPTL4, RALBP1 and TXNRD1, associated with apoptosis, SUI1, MAC30, RRAGA and CTGF, related with cell growth, HUS1 and DUSP5, related with cell cycle and proliferation, ATF4 and CEBPG, associated with transcription factor, BTG1 and VEGF, associated with angiogenesis, FDPS, FCER1G, GPA33 and EPHA4 associated with signal transduction and receptor activity and AKR1C2 and UGTA10 related with carcinogenesis were detected in increased levels. The genes that showed increaced expression in the oral squamous cell carcinoma cell line treated with Cyclosporin A were CYR61, SERPINB2, SSR3 and UPA3A which are known as genes associated with cell growth, carcinogenesis, receptor activity and transcription factor. The genes expressed in the HN22 cell line treated with cyclosporin combined with $taxol^{(R)}$ were ALCAM and GTSE1 associated with cancer invasiveness and cell cycle regulation.

• KSBB Journal
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• 제23권3호
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• pp.231-238
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• 2008

암세포의 침윤은 숙주 조직의의 기저막과 세포외 기질을 침투함으로써 일어난다. 침윤과 전이과정에는 단백질가수분해 효소인 matrix metalloproteinases (MMPs)가 깊이 연관되어 있는 것으로 알려져 있으며, MMP의 가수분해 활성은 tissue inhibitors of metalloproteinases (TIMPs)라는 억제 단백질에 의해 억제된다. TIMP-2는 21kDa 크기의 포유류 단백질로 대장균에서 과발현 시 다른 많은 포유류 단백질과 마찬가지로 가용성이 낮은 봉입체 형태로 발현된다. TIMP-2 단백질의 접힘에 6개의 이황화결합이 필요하고, 이는 일반적으로 대장균 환경은 적합하지 않다. 본 연구에서는 대장균에서 불가용성으로 발현되는 TIMP-2 유전자를 유전자셔플링 기법의 한 가지인 StEP (staggered extension process)를 변형하고 동시에 $Mn^{2+}$ 농도 변화와 dGTP 불균형을 이용한 무작위 돌연변이 기법을 혼용하여 대장균에서 가용성 TMP-2 재조합 변이체를 생성하고자 하였다. 무작위로 재조합된 TIMP-2 유전자 중에서 가용성으로 발현되는 TIMP-2 유전자를 선별하기 위해서 chloramphenicol acetyltransferase (CAT)-융합 방법을 도입하였다. CAT 유전자가 가용성으로 발현되는 재조합 TIMP-2 유전자에 융합되면 이를 갖는 E. coli는 높은 chloramphenicol 환경에서 생존이 가능하게 된다. 이러한 in virro mutageuesis 기법과 CAT-융합 방법으로 대장균 가용성 TIMP-2 재조합 변이체를 14가지 얻을 수 있었다. 변이체 TIMP-2의 아미노산서열 분석과 구조 분석 결과 주로 소수성 아미노산이 친수성 아미노산으로 전환되었고, MMP와의 결합이 관여하지 않는 C-말단 부위에 돌연변이가 집중되어 있었다. 본 연구에서 개발된 간편하고 새로운 in vitro 재조합 방법과 CAT을 이용한 스크리닝 기법은 다른 많은 대장균 내 불가용성 단백질의 발현에도 사용될 수 있을 것으로 사료된다.

• 한국작물학회지
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• 제51권spc1호
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• pp.283-291
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• 2006

To investigate seed non destructive and fast determination technique utilizing near infrared reflectance spectroscopy (NIRs) for screening ultra high oleic (C18:1) and linoleic (C18:2) fatty acid content sesame varieties among genetic resources and lines of pedigree generations of cross and mutation breeding were carried out in National Institute of Crop Science (NICS). 150 among 378 landraces and introduced cultivars were released to analyse fatty acids by NIRs and gas chromatography (GC). Average content of each fatty acid was 9.64% in palmitic acid (C16:0), 4.73% in stearic acid (C18:0), 42.26% in oleic acid and 43.38% in linoleic acid by GC. The content range of each fatty acid was from 7.29 to 12.27% in palmitic, 6.49% from 2.39 to 8.88% in stearic, 12.59% of wider range compared to that of stearic and palmitic from 37.36 to 49.95% in oleic and of the widest from 30.60 to 47.40% in linoleic acid. Spectrums analyzed by NIRs were distributed from 400 to 2,500 nm wavelengths and varietal distribution of fatty acids were appeared as regular distribution. Varietal differences of oleic acid content good for food processing and human health by NIRs was 14.08% of which 1.49% wider range than that of GC from 38.31 to 52.39%. Varietal differences of linoleic acid content by NIRs was 16.41% of which 0.39% narrower range than that of GC from 30.60 to 47.01%. Varietal differences of oleic and linoleic acid content in NIRs analysis were appeared relatively similar inclination compared with those of GC. Partial least square regression (PLSR) among multiple variant regression (MVR) in NIRs calibration statistics was carried out in spectrum characteristics on the wavelength from 700 to 2,500 nm with oleic and linoleic acids. Correlation coefficient of root square (RSQ) in oleic acid content was 0.724 of which 72.4 percent of sample varieties among all distributed in the range of 0.570 percent of standard error when calibrated (SEC) which were considerably acceptable in statistic confidence significantly for analysis between NIRs and GC. Standard error of cross validation (SECV) of oleic acid was 0.725 of which distributed in the range of 0.725 percent standard error among the samples of mother population between analyzed value by NIRs analysis and analyzed value by GC. RSQ of linoleic acid content was 0.735 of which 73.5 percent of sample varieties among all distributed in the range of 0.643 percent of SEC. SECV of linoleic acid was 0.711 of which distributed in the range of 0.711 percent standard error among the samples of mother population between NIRs analysis and GC analysis. Consequently, adoption NIR analysis for fatty acids of oleic and linoleic instead that of GC was recognized statistically significant between NIRs and GC analysis through not only majority of samples distributed in the range of negligible SEC but also SECV. For enlarging and increasing statistic significance of NIRs analysis, wider range of fatty acids contented sesame germplasm should be kept on releasing additionally for increasing correlation coefficient of RSQ and reducing SEC and SECV in the future.

• 생명과학회지
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• 제18권10호
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• pp.1377-1383
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• 2008

본 연구는 발효 김치 액으로부터 덱스트란 생산 균주를 분리하고 생산 최적 생산 조건을 정하기 위하여 반응표면 분석법을 이용하였다. 발효 조건의 독립변수들은 배양 온도,pH, 효모 추출물의 농도, 온도, 기질의 농도로 정하고 Box- Benken 디자인를 이용하여 실험을 설계하였다. 최종 분리된 균주는 Leuconostoc sp. strain SKY로 잠정적으로 명하였다. 연구 결과 덱스트란 생산은 3.90 - 22.40 g/l이고, 균체량 생산은 0.69-2.85 g/l, 수율은 0.10-0.64, 생산 속도 0.16-0.85 g/l-hr의 범위에서 분석이 되었다. 표면반응분석 결과 덱스트란 생산에 가장 영향을 미치는 것은 배양 pH이고 다음에 효모 추출물의 농도 그리고 온도의 순으로 나타났다. 균체량 생산에 가장 영향을 미치는 것은 배양 pH이고 다음에 효모 추출물의 농도 그리고 온도의 순으로 나타났다. 생산 수율에 가장 영향을 미치는 것은 배양 pH 이고 다음에 효모 추출물의 농도 그리고 온도의 순으로 나타났다. 덱스트란 생산 속도에 가장 영향을 미치는 것은 배양 pH이고 다음에 효모 추출물의 농도 그리고 온도의 순으로 나타났다. 결론적으로 최적 생산 조건은 온도는 $27-28^{\circ}C$이고, pH는 7.0이며, 효묘 추출물은 6-7%의 범위에서 결정이 되었다. 이러한 조건에서 생산된 덱스트란 양은 22g/l이고, 생산 수율은 약 60%정도이며, 생산 속도는 0.8g/l/hr이었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권3호
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• pp.245-253
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• 2000

The development and progression of oral cancer is associated with an accumulation of multiple genetic alterations through the multistep processes. Comparative genomic hybridization(CGH), newly developed cytogenetic and molecular biologic technique, has been widely accepted as a useful method to allow the detection of genetic imbalance in solid tumors and the screening for chromosome sites frequently affected by gains or losses in DNA copy number. The authors examined 19 primary oral squamous cell carcinomas using CGH to identify altered chromosome regions that might contain novel oncogenes and tumor suppressor genes. Interrelationship between these genetic aberrations detected and major oncogenes and tumor suppressor genes previously recognized in carcinogenesis of oral cancers was studied. 1. Changes in DNA copy number were detected in 14 of 19 oral cancers (78.9%, mean: 5.58, range: $3{\sim}13$). High level amplification was present in 4 cases at 9p23, $12p21.1{\sim}q13.1$, 3q and $8q24{\sim}24.3$. Fourteen cases(78.9%, mean: 3.00, range: $1{\sim}8$) showed gains of DNA copy number and 12 cases(70.5%, mean: 2.58, range: $1{\sim}9$) revealed losses of DNA copy number. 2. The most common gains were detected on 3q(52.6%), 5p(21.0%), 8q(21.0%), 9p(21.0%), and 11q(21.0%). The losses of DNA copy number were frequently occurred at 9p(36.8%), 17q(36.8%), 13q(26.3%), 4p(21.0%) and 9p(21.0%). 3. The minimal common regions of gains were repeatedly observed at $3q24{\sim}26.7$, $3q27{\sim}29$, $1q22{\sim}31$, $5p12{\sim}13.3$, $8q23{\sim}24$, and 11q13.1-13.3. The minimal common regions of losses were detected at $9q11{\sim}21.3$, 17p31, $13q22{\sim}34$, and 14p16. 4. In comparison of CGH results with tumor stages, the lower stage group showed more frequent gain at 3q, 5q, 9p, and 14q, whereas gains at 1q($1q22{\sim}31$) and 11q($11q13.1{\sim}13.3$) were mainly detected in higher stage group. The loss at $13q22{\sim}34$ was exclusively detected in higher stage. The results indicate that the most frequent genetic alterations in the development of oral cancers were gains at $3q24{\sim}26.3$, $1q22{\sim}31$, and $5p12{\sim}13.3$ and losses at $9q11{\sim}21.3$, 17p31, and 13q. It is suggested that genetic alterations manifested as gains at $3q24{\sim}26.3$, $3q27{\sim}29$, $5p12{\sim}13.3$ and 5p are associated with the early progression of oral cancer. Gains at $1q22{\sim}31$ and $11q13.1{\sim}13.3$ and loss at 13q22-34 could be involved in the late progression of oral cancers.

• 한국식품영양과학회지
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• 제42권10호
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• pp.1673-1681
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• 2013

시판 냉동 다진 마늘 5종(중국산 3종, 국산 2종)을 대상으로 DEFT/APC, 전자코 분석, PSL, TL 및 ESR 분석을 이용하여 사전살균처리 및 조사 여부를 모니터링 하였다. DEFT/APC 분석 결과 중국산 시료에서 DEFT값(생균수+사균수)은 7.9~8.3 log CFU/g으로 높은 값을 나타내었으나, APC(생균수)는 4.2~4.8 log CFU/g으로 낮은 값을 나타내어 사전살균처리 가능성이 확인되었다. 그러나 국산 시료는 DEFT값과 APC 값의 차이가 크게 나타나지 않아 사전살균처리되지 않은 것으로 판단되었다. 전자코를 이용한 조사여부 스크리닝 결과, 중국산 시료는 미지시료와 1 kGy 조사시료간에 있어서 차이가 불분명하여 조사여부 확인이 어려운 반면, 국산 시료는 그 차이가 명확히 구분되어서 사전 조사처리 되지 않았음을 확인할 수 있었다. PSL 분석 결과, 미지시료 5종 모두 700 이하의 PCs(-)을 나타내었으며, 1 kGy의 선량으로 재조사하여 얻은 PSL ratio 역시 10배 이상으로 나타나, 모든 시료가 사전 조사되지 않은 시료로 확인되었다. 한편 TL 분석에서 $TL_1$ 발광곡선은 국산 2종의 미지시료는 $300^{\circ}C$ 이상에서, 중국산 3종은 $240{\sim}250^{\circ}C$에서 약한 발광곡선을 나타내었다. 이상의 결과를 검증하기 위하여 재조사(1 kGy)에 의한 $TL_2$ 발광곡선을 측정한 결과, 국산 및 중국산 모두 $150{\sim}250^{\circ}C$에서 발광피크를 나타내면서 TL ratio($TL_1/TL_2$)가 0.1 이하로 비 조사(negative)로 나타났다. 그러나 중국산 3종의 $TL_1$ 발광곡선의 온도범위를 고려해 본다면 조사처리의 가능성이 높게 나타났다. 그리하여 ESR 분석을 실시한 결과, 중국산 3종 시료는 미지시료 및 1 kGy 조사시료 모두 방사선 유래의 특이적인 cellulose signal이 관찰되어 $TL_1$ 결과를 잘 뒷받침하였다. 이와 같이 냉동 다진 마늘의 조사여부를 효과적으로 확인하기 위해서는 물리적 분석법의 다중적 활용이 필요한 것으로 나타났다.