• 제목/요약/키워드: Materials science and engineering

검색결과 16,187건 처리시간 0.051초

Prediction of Lung Cancer Based on Serum Biomarkers by Gene Expression Programming Methods

  • Yu, Zhuang;Chen, Xiao-Zheng;Cui, Lian-Hua;Si, Hong-Zong;Lu, Hai-Jiao;Liu, Shi-Hai
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권21호
    • /
    • pp.9367-9373
    • /
    • 2014
  • In diagnosis of lung cancer, rapid distinction between small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) tumors is very important. Serum markers, including lactate dehydrogenase (LDH), C-reactive protein (CRP), carcino-embryonic antigen (CEA), neurone specific enolase (NSE) and Cyfra21-1, are reported to reflect lung cancer characteristics. In this study classification of lung tumors was made based on biomarkers (measured in 120 NSCLC and 60 SCLC patients) by setting up optimal biomarker joint models with a powerful computerized tool - gene expression programming (GEP). GEP is a learning algorithm that combines the advantages of genetic programming (GP) and genetic algorithms (GA). It specifically focuses on relationships between variables in sets of data and then builds models to explain these relationships, and has been successfully used in formula finding and function mining. As a basis for defining a GEP environment for SCLC and NSCLC prediction, three explicit predictive models were constructed. CEA and NSE are requentlyused lung cancer markers in clinical trials, CRP, LDH and Cyfra21-1 have significant meaning in lung cancer, basis on CEA and NSE we set up three GEP models-GEP 1(CEA, NSE, Cyfra21-1), GEP2 (CEA, NSE, LDH), GEP3 (CEA, NSE, CRP). The best classification result of GEP gained when CEA, NSE and Cyfra21-1 were combined: 128 of 135 subjects in the training set and 40 of 45 subjects in the test set were classified correctly, the accuracy rate is 94.8% in training set; on collection of samples for testing, the accuracy rate is 88.9%. With GEP2, the accuracy was significantly decreased by 1.5% and 6.6% in training set and test set, in GEP3 was 0.82% and 4.45% respectively. Serum Cyfra21-1 is a useful and sensitive serum biomarker in discriminating between NSCLC and SCLC. GEP modeling is a promising and excellent tool in diagnosis of lung cancer.

Synthesis and Photovoltaic Properties of Alternating Conjugated Polymers Derived from Thiophene-Benzothiadiazole Block and Fluorene/Indenofluorene Units

  • Li, Jianfeng;Tong, Junfeng;Zhang, Peng;Yang, Chunyan;Chen, Dejia;Zhu, Yuancheng;Xia, Yangjun;Fan, Duowang
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권2호
    • /
    • pp.505-512
    • /
    • 2014
  • A new donor-accepter-donor-accepter-donor (D-A-D-A-D) type 2,1,3-benzothiadiazole-thiophene-based acceptor unit 2,5-di(4-(5-bromo-4-octylthiophen-2-yl)-2,1,3-benzothiadiazol-7-yl)thiophene ($DTBTTBr_2$) was synthesized. Copolymerized with fluorene and indeno[1,2-b]fluorene electron-rich moieties, two alternating narrow band gap (NBG) copolymers PF-DTBTT and PIF-DTBTT were prepared. And two copolymers exhibit broad and strong absorption in the range of 300-700 nm with optical band gap of about 1.75 eV. The highest occupied molecular orbital (HOMO) energy levels vary between -5.43 and -5.52 eV and the lowest unoccupied molecular orbital (LUMO) energy levels range from -3.64 to -3.77 eV. Potential applications of the copolymers as electron donor material and $PC_{71}BM$ ([6,6]-phenyl-$C_{71}$ butyric acid methyl ester) as electron acceptors were investigated for photovoltaic solar cells (PSCs). Photovoltaic performances based on the blend of PF-DTBTT/$PC_{71}BM$ (w:w; 1:2) and PIF-DTBTT/$PC_{71}BM$ (w:w; 1:2) with devices configuration as ITO/PEDOT: PSS/blend/Ca/Al, show an incident photon-to-current conversion efficiency (IPCE) of 2.34% and 2.56% with the open circuit voltage ($V_{oc}$) of 0.87 V and 0.90 V, short circuit current density ($J_{sc}$) of $6.02mA/cm^2$ and $6.12mA/cm^2$ under an AM1.5 simulator ($100mA/cm^2$). The photocurrent responses exhibit the onset wavelength extending up to 720 nm. These results indicate that the resulted narrow band gap copolymers are viable electron donor materials for polymer solar cells.

Prognostic Value of Sarcopenia and Myosteatosis in Patients with Resectable Pancreatic Ductal Adenocarcinoma

  • Dong Wook Kim;Hyemin Ahn;Kyung Won Kim;Seung Soo Lee;Hwa Jung Kim;Yousun Ko;Taeyong Park;Jeongjin Lee
    • Korean Journal of Radiology
    • /
    • 제23권11호
    • /
    • pp.1055-1066
    • /
    • 2022
  • Objective: The clinical relevance of myosteatosis has not been well evaluated in patients with pancreatic ductal adenocarcinoma (PDAC), although sarcopenia has been extensively researched. Therefore, we evaluated the prognostic value of muscle quality, including myosteatosis, in patients with resectable PDAC treated surgically. Materials and Methods: We retrospectively evaluated 347 patients with resectable PDAC who underwent curative surgery (mean age ± standard deviation, 63.6 ± 9.6 years; 202 male). Automatic muscle segmentation was performed on preoperative computed tomography (CT) images using an artificial intelligence program. A single axial image of the portal phase at the inferior endplate level of the L3 vertebra was used for analysis in each patient. Sarcopenia was evaluated using the skeletal muscle index, calculated as the skeletal muscle area (SMA) divided by the height squared. The mean SMA attenuation was used to evaluate myosteatosis. Diagnostic cutoff values for sarcopenia and myosteatosis were devised using the Contal and O'Quigley methods, and patients were classified according to normal (nMT), sarcopenic (sMT), myosteatotic (mMT), or combined (cMT) muscle quality types. Multivariable Cox regression analyses were conducted to assess the effects of muscle type on the overall survival (OS) and recurrence-free survival (RFS) after surgery. Results: Eighty-four (24.2%), 73 (21.0%), 75 (21.6%), and 115 (33.1%) patients were classified as having nMT, sMT, mMT, and cMT, respectively. Compared to nMT, mMT and cMT were significantly associated with poorer OS, with hazard ratios (HRs) of 1.49 (95% confidence interval, 1.00-2.22) and 1.68 (1.16-2.43), respectively, while sMT was not (HR of 1.40 [0.94-2.10]). Only mMT was significantly associated with poorer RFS, with an HR of 1.59 (1.07-2.35), while sMT and cMT were not. Conclusion: Myosteatosis was associated with poor OS and RFS in patients with resectable PDAC who underwent curative surgery.

『東醫寶鑑』의 熟地黃 제조방법 (How to Prepare Rehmanniae Radix Preparata Described in the 『Treasured Mirror of Eastern Medicine』)

  • 노종성;윤미정;신순식
    • 대한한의학방제학회지
    • /
    • 제24권1호
    • /
    • pp.17-30
    • /
    • 2016
  • Objectives Rehmanniae Radix Preparata was prepared in the traditional Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine(Donguibogam)』 with a view to measuring the contents of 5-Hydroxymethyl-2-furaldehyde(5-HMF) at individual stages of steaming and sundrying and identifying new chemical components.Methods Based on the traditional Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』, Rehmanniae Radix Preparata steamed and sundried once through nine times was prepared. Thereafter, 5-HMF contents were analyzed and new chemical components were identified in the Rehmanniae Radix Preparata using Waters HPLC e2695, 2640 detectors, a Waters Acquity UPLC system, and a Micromass Q-TOF Premier mass spectrometer.Results The Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』 is a unique preparation method in Republic of Korea different from that in China. In the first stage of the method, fresh Rehmanniae Radix Crudus was divided into high quality, medium quality, and low quality ones named Rehmanniae Radix Crudus (Caelum)(天黃), Rehmanniae Radix Crudus (Homo)(人黃), and Rehmanniae Radix Crudus (Terra)(地黃) respectively to use Rehmanniae Radix Crudus (Caelum) and Rehmanniae Radix Crudus (Homo) for preparation of juice while using Rehmanniae Radix Crudus (Terra) to make Rehmanniae Radix Preparata. In the second stage, Rehmanniae Radix Crudus (Caelum) and Rehmanniae Radix Crudus (Terra) were made into juice and Rehmanniae Radix Crudus (Terra) was soaked in the juice. In the third stage, among auxiliary materials, rice wine named Purum Vinum Oryzae(淸酒) brewed from sticky rice was sprinkled on Rehmanniae Radix Crudus (Terra) to the extent that Rehmanniae Radix Crudus (Terra) became wet. In the fourth stage, Rehmanniae Radix Preparata steamed in earthenware steamer was dried under natural sunlight. The contents of 5-HMF in Rehmanniae Radix Preparata steamed and sundried once through nine times were shown to be below 0.1% in all cases. Pomolic acid was identified as a new chemical component.Conclusions In conclusion, the Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』 is thought to be a unique preparation method in South Korea in which Rehmanniae Radix Preparata is completed through the first stage in which fresh Rehmanniae Radix Crudus collected from fields is divided into high, medium, and low quality ones and fresh Rehmanniae Radix Crudus juice is made, the second stage in which the high quality fresh Rehmanniae Radix Crudus is soaked in the fresh Rehmanniae Radix Crudus juice, the third stage in which the fresh Rehmanniae Radix Crudus is steamed, and the fourth stage in which the steamed Rehmanniae Radix Crudus is dried.

대학기록관 설립의 필요조건: '미성숙한' 기록관리 방법의 시험 운용 방안 (A Necessary Conditions of Building University Archives: For the Tentative Application of an Immature Archival Method and Program prior to Building Archives)

  • 이종흡
    • 기록학연구
    • /
    • 제3호
    • /
    • pp.33-64
    • /
    • 2001
  • This essay introduces the basic method and program required to meet some necessary conditions of building university archives. By the phrase 'method and program', I intend the effective means of regularly but circumstantially controling the ways to the archival purposes proper which can be defined as the keeping of evidences and the broadening of information pool in terms of the evidential and informational natures or values of records. My starting point is about the matters of overcoming a standard method of induction which has long prescribed much passive procedures in the archival work. Considering the differences in the records and archives management-practices between West and Korea, I tentatively try to add some active elements to the archival work among which the collection for the expanding evidences and informations may firstly emphasized. While this collecting activity normally depends on the existing 'collections' and 'manuscripts', I cannot exclude the possibility of collections the materials, being likely to be registered in any poor or insufficient record groups. In the similar context, this kind of activity may and must be expanded beyond the university boundaries so at to arrange the cornerstones of archive-based local studies in the various disciplines. Here I premise another role of university archives, the role as 'science archives'. These archives within university archives seem likely to function in likewise the special collections within Western university libraries. What I mean here, however, is the archival groups purposedly gathered or acquisited according to more detail and narrower plan in order to meet the various demands from the different disciplines for the primary sources. The archival procedures from this revised method and program may, I hope, satisfy some of the preconditions of building university archives before the archives will actually function as a sub-institution of an university preserving legal, administrative and financial evidences, thus keeping identity and continuity of the university on the one hand, and as a local information center of supplying the archival contents on effectual demand from the field of local studies on the other. Finally, I conclude with a suggestion concerning the cooperation of all the parties of archival works. Proposing the 'Regional Research Center Program' in the field of technology and engineering as a model for the cooperation, I suggest that universities, private/public organizations, and central and local governments may work together for surveying the scattered ancient and modern documents as well as for building archives under the matching fund.

Volumetric analysis of mucous retention cysts in the maxillary sinus: A retrospective study using cone-beam computed tomography

  • Hung, Kuofeng;Hui, Liuling;Yeung, Andy Wai Kan;Wu, Yiqun;Hsung, Richard Tai-Chiu;Bornstein, Michael M.
    • Imaging Science in Dentistry
    • /
    • 제51권2호
    • /
    • pp.117-127
    • /
    • 2021
  • Purpose: The aim of this study was to evaluate the volumetric characteristics of mucous retention cysts(MRCs) in the maxillary sinus and to analyze potential associations of MRCs with dentoalveolar pathologies. Materials and Methods: Cone-beam computed tomography (CBCT) scans exhibiting bilateral maxillary sinuses that were acquired from January 2016 to February 2019 were initially screened. A total of 227 scans(454 sinuses) that fulfilled the inclusion criteria were included. The presence, location, and volumetric characteristics of the diagnosed MRCs were evaluated on CBCT images using the 3D-Slicer software platform. The presence of MRCs was correlated with potential influencing factors including age, sex, and dentoalveolar pathology. For MRCs located on the sinus floor, factors with a potential impact on the volume, surface, and diameter were analyzed. Results: An MRC was present in 130 (28.6%) of the 454 sinuses. Most MRCs were located on the sinus walls and floor. The mean MRC volume, surface, and diameter were 551.21±1368.04 mm3, 228.09±437.56 mm2, and 9.63±5.40 mm, respectively. Significantly more sinuses with associated endodontically treated teeth/periapical lesions were diagnosed with an MRC located on the sinus floor. For MRCs located on the sinus floor, endodontic status exhibited a significant association with increased volume, surface, and diameter. Conclusion: Periapical lesions might be a contributing factor associated with the presence and volume of MRCs located on the sinus floor. The 3D-Slicer software platform was found to be a useful tool for clinicians to analyze the size of MRCs before surgical interventions such as sinus floor elevation procedures.

원심 주조된 타이타늄과 타이타늄 합금의 레이저 용접 특성 (MECHANICAL PROPERTIES OF LASER-WELDED CAST TITANIUM AND TITANIUM ALLOY)

  • 윤미경;김현승;양홍서;방몽숙;박상원;박하옥;이광민
    • 대한치과보철학회지
    • /
    • 제44권5호
    • /
    • pp.642-653
    • /
    • 2006
  • Purpose : The purpose of this study was to investigate the effect of the output energy(voltage) of laser welding on the strength and properties of joint of cast titanium(CP Gr II) and titanium alloy(Ti-6Al-4V). Material and method : Cast titanium and its alloy rods(ISO6871) were prepared and perpendicularly cut at the center of the rod. After the cut halves were fixed in a jig, and the joints welded with a laser-welding machine at several levels of output voltage of $200V{\sim}280V$. Uncut specimens served as the non-welded control specimens The pulse duration and pulse spot size employed in this study were 10ms and 1.0mm respectively. Tensile testing was conducted at a crosshead speed of 0.5mm/min. The ultimate tensile strength(MPa) was recorded, and the data (n=6) were statistically analyzed by one-way analysis of variance(ANOVA) and Scheffe's test at ${\alpha}$=0.05. The fracture surface of specimens investigated by scanning electron microscope (SEM). Vickers microhardness was measured under 500g load of 15seconds with the optimal condition of output voltage 280V. Results : The results of this study were obtained as follows, 1. When the pulse duration and spot size were fixed at 10ms and 1.0mm respectively, increasing the output energy(voltage) increased UTS values and penetration depth of laser welded to titanium and titanium alloy. 2. For the commercial titanium grade II, ultimate tensile strength(665.3MPa) of the specimens laser-welded at voltage of 280V were not statistically(p>0.05) different from the non-welded control specimens (680.2MPa). 3. For the titanium alloy(Ti-6Al-4V), ultimate tensile strength(988.3MPa) of the specimens laser-welded at voltage of 280V were statistically(p<0.05) different from the non-welded control specimens (665.0MPa). 4. The commercial titanium grade II and titanium alloy(Ti-6Al-4V) were Vickers microhardness values were increased in the fusion zone and there were no significant differences in base metal, heat-affected zone.

약용 식물 발효액(들빛)의 항산화, Angiotensin Converting Enzyme 저해 및 Nitric Oxide 생성 조절 효과 (Antioxidative activity and Angiotensin Converting Enzyme Inhibitory activity of Fermented Medical Plants (DeulBit) and Its Modulatory Effects of Nitric Oxide Production)

  • 조은경;갈상완;최영주
    • Journal of Applied Biological Chemistry
    • /
    • 제53권2호
    • /
    • pp.91-98
    • /
    • 2010
  • 본 연구에서는 결명자, 오미자, 구기자, 박하, 국화, 산마, 생강, 둥글레, 감초, 오가피, 녹차, 다시마를 발효시킨 들빛 발효액으로 여러 가지 생리활성에 대하여 분석하였다. 우선, 들빛 발효액의 플라보노이드 함량과 DPPH 활성을 측정하였다. 그 결과 들빛 발효액의 총 플라보이드 함량은 $3.4{\pm}0.5\;mg/g$으로, DPPH법을 통해 측정한 들빛 발효액의 radical 소거능은 96%로 나타났다. 들빛 발효액의 SOD 유사활성은 29%로 나타내었고, XOase에 의해 생성된 superoxide radical 소거능은 88%로 높게 나타났다. 들빛 발효액의 항고혈압 측정실험에서는 66%의 저해률을 나타내어 ACE 저해 활성이 뛰어난 것으로 나타났다. 혈전분해능에 대한 들빛 발효액의 분석 결과는 혈전용해제로 알려져 있는 plasmin과 유사한 활성을 보이고 있다. 들빛 발효액과 면역활성과의 연관성은 NO 생성 증가율과 LPS에 의해 유도되는 NO 생성 억제율 분석으로 조사되었다. 그 결과, 들빛 발효액은 무려 15배의 높은 NO 생성 증가율을 보였다. 또한 LPS에 의해 유도된 NO 생성 억제율은 들빛 발효액 100%에서 42%로 나타나 높은 면역조절능을 나타내었다. 이상의 결과는 들빛 발효액의 우수한 생리활성을 증명하고 있고, 항산화력, 항고혈압 효과, 혈전분해능 및 면역 조절활성이 높은 것으로 나타나 기능성 음료의 소재로서 그 활용도가 높을 것으로 판단된다.

Reliability of Skeletal Muscle Area Measurement on CT with Different Parameters: A Phantom Study

  • Dong Wook Kim;Jiyeon Ha;Yousun Ko;Kyung Won Kim;Taeyong Park;Jeongjin Lee;Myung-Won You;Kwon-Ha Yoon;Ji Yong Park;Young Jin Kee;Hong-Kyu Kim
    • Korean Journal of Radiology
    • /
    • 제22권4호
    • /
    • pp.624-633
    • /
    • 2021
  • Objective: To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters. Materials and Methods: A phantom, simulating the L2-4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings. Results: The skeletal muscle area (threshold, -29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30-150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0-44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used. Conclusion: Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

파프리카 재배 벤로형 유리온실에서 난방에너지 절감 패키지 기술 적용효과 (Application Effect of Heating Energy Saving Package on Venlo Type Glasshouse of Paprika Cultivation)

  • 권진경;전종길;김승희;김형권
    • 생물환경조절학회지
    • /
    • 제25권4호
    • /
    • pp.225-231
    • /
    • 2016
  • 본 연구에서는 유리온실 경영비 절감을 위한 고효율 난방기술을 개발하기 위하여 지하수열원 히트펌프, 알루미늄 다겹보온커튼, 근권부 국소난방장치를 조합한 난방 패키지 모델을 구성하고 파프리카 재배 벤로형 유리온실에 적용 시험을 수행하였다. 적용효과 분석을 위하여 관행 경유온수보일러와 일반 보온커튼을 설치한 대조구 온실과 비교시험을 통해 온실환경, 난방비용, 작물생육 등을 검토하였다. 알루미늄 다겹보온커튼과 일반 부직포 보온커튼을 설치한 온실에 대한 무가온 조건에서의 야간온도 비교시험에서 알루미늄 다겹보온커튼 설치 온실의 온도가 일반 부직포 보온커튼 설치 온실에 비해 평균 $2.2^{\circ}C$ 더 높게 유지됨을 확인하였다. 또한 근권부 국소 난방장치를 설치한 온실에서 미설치 온실에 비해 야간 난방 중의 베드내부 근권온도가 $4.7^{\circ}C$ 더 높게 유지됨을 확인하였다. 난방패키지를 구성하는 지하수열원 히트펌프의 난방성능을 분석한 결과 지하수를 직접 열원으로 이용하는 시스템 특성상 난방성능계수는 평균 3.7로 비교적 높게 나타났다. 난방패키지를 적용한 처리구 온실과 관행 난방의 대조구 온실에 대하여 연료소비량을 계측한 결과 10a($1,000m^2$)당 대조구 온실은 경유 14,071L, 전력 364kWh를 소비하였고, 처리구는 전력 35,082kWh를 소비하여 난방비용 기준으로 대조구 온실의 비용 절감율은 87%로 나타났다. 처리구 및 대조구 온실의 작물생육을 비교한 결과 초장과 엽록소 함량에서 차이가 발생하였으나 두 온실의 난방온도가 거의 동일하므로 전체적인 생육은 큰 차이가 없는 것으로 분석되었다. 원예시설의 난방에너지 절감효과를 극대화하기 위해서는 본 연구의 난방패키지를 구성하는 개별 기술뿐 아니라 이미 개발된 고효율 공조기 이용기술, 보온성 향상기술, 온도관리 기술 등을 지역, 시설, 작목, 작형 등에 최적화하여 조합할 수 있는 추가적 패키지 모델의 개발 연구가 필요한 것으로 판단되었다.