• Title/Summary/Keyword: can materials

Search Result 20,788, Processing Time 0.056 seconds

Development of a Molecular Selection Marker for Bacillus licheniformis K12 (Bacillus licheniformis K12 균주 분자 선발 마커 개발)

  • Young Jin Kim;Sam Woong Kim;Tae Wok Lee;Won-Jae Chi;Woo Young Bang;Ki Hwan Moon;Tae Wan Kim;Kyu Ho Bang;Sang Wan Gal
    • Journal of Life Science
    • /
    • v.33 no.10
    • /
    • pp.808-819
    • /
    • 2023
  • This study was conducted to develop a selection marker for the identification of the Bacillus licheniformis K12 strain in microbial communities. The strain not only demonstrates good growth at moderate temperatures but also contains enzymes that catalyze the decomposition of various polymer materials, such as proteases, amylases, cellulases, lipases, and xylanases. To identify molecular markers appropriate for use in a microbial community, a search was conducted to identify variable gene regions that show considerable genetic mutations, such as recombinase, integration, and transposase sites, as well as phase-related genes. As a result, five areas were identified that have potential as selection markers. The candidate markers were two recombinase sites (BLK1 and BLK2), two integration sites (BLK3 and BLK4), and one phase-related site (BLK5). A PCR analysis performed with different Bacillus species (e.g., B. licheniformis, Bacillus velezensis, Bacillus subtilis, and Bacillus cereus) confirmed that PCR products appeared at specific locations in B. licheniformis: BLK1 in recombinase, BLK2 in recombinase family protein, and BLK3 and BLK4 as site-specific integrations. In addition, BLK1 and BLK3 were identified as good candidate markers via a PCR analysis performed on subspecies of standard B. licheniformis strains. Therefore, the findings suggest that BLK1 can be used as a selection marker for B. licheniformis species and subspecies in the microbiome.

Importance and requirements for dental prosthesis order platform services: a survey of dental professionals (치과 보철물 거래 플랫폼 서비스의 중요성과 요구사항: 치과 전문가 설문조사)

  • Gyu-Ri Kim;Keunbada Son;Du-Hyeong Lee;So-Yeun Kim;Myoung-Uk Jin;Kyu-Bok Lee
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.39 no.3
    • /
    • pp.105-118
    • /
    • 2023
  • Purpose: This study aimed to gain better understanding of the importance of dental prosthesis order platform services and to identify the essential elements for their enhancement and wider adoption among dental professionals. Materials and Methods: A survey was conducted to assess the perspectives of dentists, dental technicians, dental hygienists, and dental industry professionals toward dental prosthesis ordering and associated platform services (a total of 53 respondents). The questionnaire was devised after an expert review and assessed for reliability using Cronbach's alpha coefficient. Factor analysis revealed that 57 factors across five categories accounted for 88.417% of the total variance. The survey was administered through an online questionnaire platform, and data analysis was conducted using a statistical software, employing one-way analysis of variance and Tukey's honestly significant difference test (α = 0.05). Results: The essential elements identified were accurate information input, effective communication, delivery of distortion-free impressions, convenience in data transmission and storage, development of stable and affordable platform services (P < 0.05). Furthermore, significant differences were observed in the importance of these items based on age, dental profession, and career experience (P < 0.05). Conclusion: The dental prosthesis ordering platform services, the requirements of dental personnel were stability, economic efficiency, and ease of transmitting and storing prosthesis data. The findings can serve as important indicators for the development and improvement of dental prosthesis order platform services.

Scientific Study on Clepsydra of Changgyeonggung Palace, National Treasure for Diagnosis on State of Conservation (국보 창경궁 자격루 누기의 보존상태 진단을 위한 과학적 조사)

  • YOU Harim;LEE Jaesung;YU Jia;JO Hanui;PARK Younghwan;RYU Dongwan
    • Korean Journal of Heritage: History & Science
    • /
    • v.56 no.3
    • /
    • pp.138-156
    • /
    • 2023
  • Some of the metal cultural heritage that make up a considerable proportion of Korea's cultural heritage have been installed and displayed outdoors due to their own functions, roles, and scale. Therefore, more diverse and complex damages can occur outdoors than they are in a stable environment. Therefore, it is necessary to combine accurate diagnosis and systematic survey methods in order to utilize basic data obtained from research results as data for the long-term and continuous conservation management as well as to do the research to diagnose the conservation status of outdoor cultural heritage. The clepsydra(hereinafter referred to as Jagyeongnu) of Changgyeonggung Palace, the National Treasure has been installed and displayed outdoors since it was manufactured. Though regular conservation and maintenance of the Jagyeongnu have been carried out, damage still occurred. Therefore, the scientific research on Jagyeongnu to diagnose the state of conservation was conducted prior to the full-scale conservation treatment. First, the state of conservation was investigated with an examination of basic data, macroscopic inspections and past records of repair history according to the purpose of the research. More detailed examinations were also conducted through the 3D scan, surface pattern investigation, and color difference analysis, and the analysis on materials and contaminants were conducted through P-XRF, FT-IR, and Py-GC/MS. The scientific research reveals that squalane and silicone oil have been applied in the past for conservation treatment and directly exposed to outdoor environmental factors, which caused damage to Jagyeongnu and contaminants such as dust adhered thickly to its surface, accelerating severe damage. A greater incidence of damage was found around the part with relatively high exposure effect, which corresponded with the tendency identified by grouping color difference data. As a result of integrating various research methodologies to diagnose the state of conservation and secure basic data, the causes and types of damage were identified. Furthermore, the process of obtaining digital data to be utilized in various ways, and the color difference analysis presenting visible damage as scientific data and identifying the tendency of damage patterns were confirmed to have been effective.

A Study on the Effects of ESG Entrepreneurship Education and Participatory Learning Method on Creative Problem-Solving and Social Value Recognition (ESG기업가정신교육과 참여적 학습 방식이 '창의적 문제해결' 및 '사회적 가치 인식'에 미치는 영향에 관한 연구)

  • Lee Sunyoung;Kim Seungchul
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.18 no.2
    • /
    • pp.201-219
    • /
    • 2023
  • ESG (Environment, Social, Governance) is becoming the core of the interest of today's entrepreneurs concerning about the earth crisis. Numerous studies are going on these days about the importance of ESG, but most of them seem confined to the introductory level. This study concentrates on "ESG education" that will teach the learners how to put various ESG ideas into practice, knowing that the earth crisis would not be overcome without actual practice of those ideas. First, elementary and junior·senior high school, professors in university and educational consultants in the field designed educational programs and related content materials under "ESG entrepreneurship education" integrated with ESG and Entrepreneurship education, which have been implemented previously. Participatory learning methods are converged with the program. The researcher analyzed the learning effects in depth after implementing the programs in the education field. Thus, this study first examined the effects of key variables of ESG educational program i.e., ESG entrepreneurship education, student participatory learning, and team-based learning on creative problem-solving and social value recognition with an essential variant of ESG educational programs and identified the relations to creative problem-solving and social value recognition. Besides, this study investigated the moderating effects of school atmosphere, and teachers' enthusiasm, regarding traits of educational programs and social value recognition. Findings indicate that sub variants of the traits of educational programs i.e., ESG entrepreneurship education, student participatory learning, and team-based learning significantly affect creative problem-solving skills and social value recognition and that creative problem-solving impacts social value recognition. In addition, teachers' enthusiasm has moderating effects between traits of educational programs and social value recognition. This study provides content-program learning methods that can be practically applied in education, emphasizing practice in ESG in elementary and junior·senior high school education. Implications suggest that ESG entrepreneurship education and active participatory learning affect social value recognition and that teachers' enthusiasm plays a significant role in education.

  • PDF

Effect of surface sealant on surface roughness of dental composite with different surface roughness (서로 다른 거칠기의 복합레진에 표면 강화제 도포시 표면 거칠기의 변화)

  • Dong-Ah Shin;Seon-Ju Jin;Kkot-Byeol Bae;In-Nam Hwang
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.39 no.4
    • /
    • pp.195-203
    • /
    • 2023
  • Purpose: This study aimed to evaluate the influence of surface sealants on the surface roughness of composite resins. Materials and Methods: The study used microfilled composite resin (Metafil CX, Sun Medical Co.) and hybrid composite resin (AeliteTM LS posterior, Bisco). Sixty specimens (8 mm in diameter and 4 mm in height) of each composite resin type were prepared and divided into 3 groups. Each specimen was ground with 600, 1000, and 2000-grit sandpaper. The Surface roughness (Ra) values were measured using a surface roughness tester (SJ-301, Mytutoyo) before and after surface sealant application. Surface sealants, BisCoverTM LV (Bisco), Optiguard® (Kerr), and Seal-n-ShineTM (Pulpdent), were applied to the specimens, as instructed and observed by scanning electron microscope (JSM-7500, JEOL) and atomic force microscope (MultiMode IV, Veeco Instruments). Results: Specimens ground with 600-grit sandpaper coated with surface sealants exhibited significantly lower Ra values than the untreated group (P < 0.05). Specimens ground with 1000 and 2000-grit sandpaper showed statistically no difference. There was no significant difference in surface roughness among BisCoverTM LV, Optiguard®, and Seal-n-ShineTM. SEM and AFM revealed remarkably decreased microdefects on the surfaces of composite resins after surface sealant application. Conclusion: Surface sealants can influence surface roughness when applied on the rough surface of composite resins but not on highly polished composite resins.

Bioconversion of nutrient and phytoestrogen constituents during the solid-state fermentation of soybeans by mycelia of Tricholoma matsutake (송이버섯 균사체를 이용한 대두 고체발효 중 영양성분과 식물성 에스트로겐 성분의 생물전환)

  • Hee Yul Lee;Kye Man Cho;Ok Soo Joo
    • Food Science and Preservation
    • /
    • v.30 no.6
    • /
    • pp.1012-1028
    • /
    • 2023
  • The findings of this study confirmed the alteration of β-glucosidase activity, nutritional constituents, isoflavones, antioxidant activities, and digestive enzyme inhibition activities in soybeans during solid-state fermentation times with mycelia of Tricholoma matsutake. After nine days, the highest activity level was observed for β-glucosidase (3.90 to 38.89 unit/g) and aglycones (163.03 to 1,074.28 ㎍/g). The sum of isoflavones showed a significant decrease (3,489.41 to 1,325.66 ㎍/g) along with glycosides (2,753.87 to 212.43 ㎍/g) for fermentation, while fatty acids showed a slight increase and amino acids showed a marked increase. Total phenolic and flavonoid contents showed a corresponding increase according to fermentation times (5.58 to 15.09 GAE mg/g; 0.36 to 1.58 RE mg/g). Antioxidant and enzyme inhibition activities also increased; in particular, the highest level of scavenging activities was observed for ABTS (up 60.13 to 82.08%), followed by DPPH (up 63.92% to 71.98%) and hydroxyl (up 36.01 to 52.02%) radicals. Of particular interest, α-glucosidase (6.69 to 83.49%) and pancreatic lipase inhibition (1.22 to 77.43%) showed a marked increase. These results demonstrated that fermentation of soybeans with the mycelia of T. matsutake enhanced the nutritional and functional constituents, and the biological activities of soybeans. Thus, this fermentation technology can be used to produce a novel functional materials from soybeans.

Radiation Dose Reduction in Digital Mammography by Deep-Learning Algorithm Image Reconstruction: A Preliminary Study (딥러닝 알고리즘을 이용한 저선량 디지털 유방 촬영 영상의 복원: 예비 연구)

  • Su Min Ha;Hak Hee Kim;Eunhee Kang;Bo Kyoung Seo;Nami Choi;Tae Hee Kim;You Jin Ku;Jong Chul Ye
    • Journal of the Korean Society of Radiology
    • /
    • v.83 no.2
    • /
    • pp.344-359
    • /
    • 2022
  • Purpose To develop a denoising convolutional neural network-based image processing technique and investigate its efficacy in diagnosing breast cancer using low-dose mammography imaging. Materials and Methods A total of 6 breast radiologists were included in this prospective study. All radiologists independently evaluated low-dose images for lesion detection and rated them for diagnostic quality using a qualitative scale. After application of the denoising network, the same radiologists evaluated lesion detectability and image quality. For clinical application, a consensus on lesion type and localization on preoperative mammographic examinations of breast cancer patients was reached after discussion. Thereafter, coded low-dose, reconstructed full-dose, and full-dose images were presented and assessed in a random order. Results Lesions on 40% reconstructed full-dose images were better perceived when compared with low-dose images of mastectomy specimens as a reference. In clinical application, as compared to 40% reconstructed images, higher values were given on full-dose images for resolution (p < 0.001); diagnostic quality for calcifications (p < 0.001); and for masses, asymmetry, or architectural distortion (p = 0.037). The 40% reconstructed images showed comparable values to 100% full-dose images for overall quality (p = 0.547), lesion visibility (p = 0.120), and contrast (p = 0.083), without significant differences. Conclusion Effective denoising and image reconstruction processing techniques can enable breast cancer diagnosis with substantial radiation dose reduction.

CT Follow-Up of Postoperative Bronchopleural Fistula: Risk Factors for Progression to Chronic Complicated Infection (수술 후 기관지 흉막루의 전산화단층촬영 추적 검사: 만성 복합성 감염 진행의 위험인자 분석)

  • Ji-Yeon Han;Ki-Nam Lee;Yoo Sang Yoon;Jihyun Lee;Hongyeul Lee;Seok Jin Choi;Hye Jung Choo;Jin Wook Baek;Young Jin Heo;Gi Won Shin;Jinyoung Park;Dasom Kim
    • Journal of the Korean Society of Radiology
    • /
    • v.82 no.1
    • /
    • pp.128-138
    • /
    • 2021
  • Purpose We evaluated the risk factors for progression to chronic complicated bronchopleural fistula (BPF) after pulmonary resection using follow-up CT. Materials and Methods We retrospectively reviewed 45 cases with BPF that had undergone pulmonary resection during 2010-2018. We compared the clinical and radiological characteristics of those with complicated BPF (n = 24) and those without complicated (sterilized) BPF (n = 21). The clinical and radiological risk factors for progression to chronic complicated BPF were examined by logistic regression analysis. Results The thickness of the pleural cavity wall (p = 0.022), the size of the pleural cavity (p = 0.029), and the size increase of BPF on follow-up (p = 0.012) were significantly different between the two groups. The risk factors for progression to chronic complicated BPF were age > 70 years (odds ratio, 6.43; 95% confidence interval, 1.2-33.7), the thickness of the cavity wall > 5 mm (odds ratio, 52.5; 95% confidence interval, 5.1-545.4), and an increase in the size of the pleural cavity on follow-up CT (odds ratio, 12.5; 95% confidence interval, 2.1-73.5), only in the univariate analysis. Conclusion The risk factors for progression to chronic complicated BPF can be evaluated using follow-up CT.

Light-Chain Cardiac Amyloidosis: Cardiac Magnetic Resonance for Assessing Response to Chemotherapy

  • Yubo Guo;Xiao Li;Yajuan Gao;Kaini Shen;Lu Lin;Jian Wang;Jian Cao;Zhuoli Zhang;Ke Wan;Xi Yang Zhou;Yucheng Chen;Long Jiang Zhang;Jian Li;Yining Wang
    • Korean Journal of Radiology
    • /
    • v.25 no.5
    • /
    • pp.426-437
    • /
    • 2024
  • Objective: Cardiac magnetic resonance (CMR) is a diagnostic tool that provides precise and reproducible information about cardiac structure, function, and tissue characterization, aiding in the monitoring of chemotherapy response in patients with light-chain cardiac amyloidosis (AL-CA). This study aimed to evaluate the feasibility of CMR in monitoring responses to chemotherapy in patients with AL-CA. Materials and Methods: In this prospective study, we enrolled 111 patients with AL-CA (50.5% male; median age, 54 [interquartile range, 49-63] years). Patients underwent longitudinal monitoring using biomarkers and CMR imaging. At follow-up after chemotherapy, patients were categorized into superior and inferior response groups based on their hematological and cardiac laboratory responses to chemotherapy. Changes in CMR findings across therapies and differences between response groups were analyzed. Results: Following chemotherapy (before vs. after), there were significant increases in myocardial T2 (43.6 ± 3.5 ms vs. 44.6 ± 4.1 ms; P = 0.008), recovery in right ventricular (RV) longitudinal strain (median of -9.6% vs. -11.7%; P = 0.031), and decrease in RV extracellular volume fraction (ECV) (median of 53.9% vs. 51.6%; P = 0.048). These changes were more pronounced in the superior-response group. Patients with superior cardiac laboratory response showed significantly greater reductions in RV ECV (-2.9% [interquartile range, -8.7%-1.1%] vs. 1.7% [-5.5%-7.1%]; P = 0.017) and left ventricular ECV (-2.0% [-6.0%-1.3%] vs. 2.0% [-3.0%-5.0%]; P = 0.01) compared with those with inferior response. Conclusion: Cardiac amyloid deposition can regress following chemotherapy in patients with AL-CA, particularly showing more prominent regression, possibly earlier, in the RV. CMR emerges as an effective tool for monitoring associated tissue characteristics and ventricular functional recovery in patients with AL-CA undergoing chemotherapy, thereby supporting its utility in treatment response assessment.

Extent of Subprosthetic Pannus after Aortic Valve Replacement: Changes Over Time and Relationship with Echocardiographic Findings (대동맥판막치환술 후 발생한 판막하 판누스(Pannus): 시간에 따른 변화 및 심초음파 소견)

  • Mi Yeon Park;Hyun Jung Koo;Hojin Ha;Joon-Won Kang;Dong Hyun Yang
    • Journal of the Korean Society of Radiology
    • /
    • v.81 no.5
    • /
    • pp.1151-1163
    • /
    • 2020
  • Purpose This study aimed to evaluate changes of subprosthetic pannus on cardiac CT and determine its relationship to echocardiographic findings in patients with mechanical aortic valve replacement (AVR). Materials and Methods Between April 2011 and November 2017, 17 AVR patients (56.8 ± 8.9 years, 12% male) who showed pannus formation on CT and had undergone both follow-up CT and echocardiography were included. The mean interval from AVR to the date of pannus detection was 10.5 ± 7.1 years. In the initial and follow-up CT and echocardiography, the pannus extent and echocardiographic parameters were compared using paired t-tests. The relationship between the opening angle of the prosthetic valve and the pannus extent was evaluated using Pearson correlation analysis. Results The pannus extent was significantly increased on CT (p < 0.05). The peak velocity (3.9 ± 0.8 m/s vs. 4.2 ± 0.8 m/s, p = 0.03) and mean pressure gradient (36.4 ± 15.5 mm Hg vs. 42.1 ± 15.8 mm Hg, p = 0.03) were significantly increased. The mean opening angles of the mechanical aortic leaflets were slightly decreased, but there was no statistical significance (73.1 ± 8.3° vs. 69.4 ± 12.1°, p = 0.12). The opening angle of the prosthetic leaflets was inversely correlated with the pannus extent (r = -0.57, p < 0.001). Conclusion The pannus extent increases over time, increasing transvalvular peak velocity and the pressure gradient. CT can be used to evaluate the pannus extent associated with hemodynamic changes that need to be managed by surgical intervention.