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The computerized LASSI-BC Test versus the Standard LASSI-L Paper-and-Pencil Version in Community-Based-Samples
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作者 Rosie E. Curiel Cid Alexandra Ortega +13 位作者 Ubbo Visser Marcela Kitaigorodsky D. Diane Zheng Diana Hincapie Kirsten Horne Crenshaw Ashleigh Beaulieu Brooke Bosworth Liz Gallardo Emory Neer Sofia Ramirez Elizabeth A. Crocco Mike Georgiou Efrosyni Sfakianaki David A. Loewenstein 《Advances in Alzheimer's Disease》 CAS 2024年第1期11-25,共15页
Proactive Semantic Interference (PSI) and failure to recover from PSI (frPSI), are novel constructs assessed by the LASSI-L. These measures are sensitive to cognitive changes in early Mild Cognitive Impairment (MCI) a... Proactive Semantic Interference (PSI) and failure to recover from PSI (frPSI), are novel constructs assessed by the LASSI-L. These measures are sensitive to cognitive changes in early Mild Cognitive Impairment (MCI) and preclinical AD determined by Aβ load using PET. The goal of this study was to compare a new computerized version of the LASSI-L (LASSI-Brief Computerized) to the standard paper-and-pencil version of the test. In this study, we examined 110 cognitively unimpaired (CU) older adults and 79 with amnestic MCI (aMCI) who were administered the paper-and-pencil form of the LASSI-L. Their performance was compared with 62 CU older adults and 52 aMCI participants examined using the LASSI-BC. After adjustment for covariates (degree of initial learning, sex, education, and language of evaluation) both the standard and computerized versions distinguished between aMCI and CU participants. The performance of CU and aMCI groups using either form was relatively commensurate. Importantly, an optimal combination of Cued B2 recall and Cued B1 intrusions on the LASSI-BC yielded an area under the ROC curve of .927, a sensitivity of 92.3% and specificity of 88.1%, relative to an area under the ROC curve of .815, a sensitivity of 72.5%, and a specificity of 79.1% obtained for the paper-and-pencil LASSI-L. Overall, the LASSI-BC was comparable, and in some ways, superior to the paper-and-pencil LASSI-L. Advantages of the LASSI-BC include a more standardized administration, suitability for remote assessment, and an automated scoring mechanism that can be verified by a built-in audio recording of responses. 展开更多
关键词 Mild Cognitive Impairment Proactive Semantic Interference LASSI-L computerized Cognitive Assessment
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COMPUTER SIMULATION IN MAN-MACHINE-ENVIRONMENT SYSTEM ENGINEERING
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作者 Yuan Xiugan(Fifth Department,Beijing University of Aeronautics andAstronautics,Beijing,China,100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1995年第3期168-173,共6页
The applications and trends of computer simulation of man-machine-en-vironment systems are presented in this paper.Topics such as the modeling of a humanphysiological system,simulation of the nucro-environment in an a... The applications and trends of computer simulation of man-machine-en-vironment systems are presented in this paper.Topics such as the modeling of a humanphysiological system,simulation of the nucro-environment in an aireraft cabin,and thecomputer graphic 展开更多
关键词 computerIZED simulation human FACTORS ENGINEERING computer GRAPHICS ANALOGIES
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Micro-computerized Three-dimensional Reconstruction of the Palmar Arteries and Its Clinical Significance
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作者 张绍祥 何光篪 刘正津 《Journal of Medical Colleges of PLA(China)》 CAS 1990年第3期203-209,共7页
Thirty adult upper extremities were used to study the arteries of the hand byangiography,cross-sectional dissection and three-dimensional reconstruction withmicrocomputer.The arterial skeleton of the palm was composed... Thirty adult upper extremities were used to study the arteries of the hand byangiography,cross-sectional dissection and three-dimensional reconstruction withmicrocomputer.The arterial skeleton of the palm was composed of superficial,deep anddorsal planes.There were three main anastomotic pathways between the radial and ulnararteries or their branches in the radio-ulnar direction,while in the palmar dorsal dirce-tion there were three anastomotic zones between the palrnar and dorsal arterial plancs.The branches of the deep palmar arch radiated distally,proximally,palmarly anddorsally,so that the arch acted as the center of the arterial network of the hand.Thetransverse arterial allocations in the carpo-metacarpal segment of the palm were four intypes,but in the mid-palmar and metacarpo-phalangcal segments were three only.Accord-ing to the sources,cross-sectional area,irrigation territories and anastomoses of the ar-teries in each segment,the clinical significance in the rcplantation of the amputatcd palmshas been 展开更多
关键词 Hand ARTERIES computerS Micro-computerized three dimensional reconstruction REPLANTATION of the PALM
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Screening for lung cancer with chest computerized tomography: Is it cost efficient?
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作者 Tomasz Jaroslaw Szczesny Malgorzata Kanarkiewicz Janusz Kowalewski 《World Journal of Respirology》 2015年第2期160-165,共6页
Despite lung cancer(LC) screening by low-dose computerized tomography(LDCT) gaining many proponents worldwide, for many years it was not recognized as a life-prolonging and cost-effective procedure, until recently. Pr... Despite lung cancer(LC) screening by low-dose computerized tomography(LDCT) gaining many proponents worldwide, for many years it was not recognized as a life-prolonging and cost-effective procedure, until recently. Prospective observational studies had not been able to prove that this screening prolongs survival, but they helped to specify the inclusion and exclusion criteria. Long-awaited results of a prospective, randomized trial finally provided the evidence that LC screening with LDCT can prolong survival of the screened population. Several costeffectiveness analyses were performed to justify mass introduction of this screening. Results of these analyses are equivocal, although conclusions highly depend upon inclusion and exclusion criteria, methods of analysis and prices of medical procedures which differ between countries as well as the incidence of other pulmonary nodules, especially tuberculosis. Therefore, costeffectiveness analysis should be performed separately for every country. Cost-effectiveness depends especially upon the rate of false-positive results and the rate of unnecessary diagnostic, screening and treatment procedures. To ensure high cost-effectiveness, LC screening should be performed in accordance with screening protocol, in dedicated screening centers equipped with nodule volume change analysis, or as a prospective non-randomized trial, to ensure compliance with the inclusion and exclusion criteria. To ensure high cost-effectiveness of LC screening, future research should concentrate on determination of highrisk groups and further specifying the inclusion and exclusion criteria. 展开更多
关键词 Lung cancer Non-small cell lung cancers SCREENING COST-EFFECTIVENESS computerized tomography Low-dose computerized tomography
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COMPUTERIZED SIMULATION AND EXPERIMENTAL RESEARCH ON SOFT-SWITCHING ARC WELDING INVERTER POWER SOURCE 被引量:24
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作者 S. J. Chen S. Y. Yin L. Feng and L. Y. Li( 1) School of Materials Science and Engineering, Beijing Polytechnic University, Beijing 100022, China 2)National Key Laboratory of Advanced Welding Production Technology, HIT, Harbin 150001, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期128-132,共5页
Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic ca... Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are analyzed.The simulation results are testified by experiments.It is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source. 展开更多
关键词 ARC welding INVERTER computerIZED simulation.IGBT SOFT SWITCHING
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Identification of Porphyra lines using computerized DNA fingerprinting 被引量:7
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作者 WangBin, Jia Jianhang, Shi Jinfeng, Chen Yihua, JinDemin, Xu Pu, Mei Junxue, Weng Manli 1. Institute of Genetics, Chinese Academy of Sciences, Beijing 100101 (E-mail: mlweng@genetics. ac. cn), China 2. Jiangsu Marine Fishery Institute, Nan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第3期401-407,共7页
RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia... RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia). Eight stable and repeatable RAPD bands amplified with two primers, OPN-02 and OPJ-18, were selected for the construction of DNA fingerprinting. The RAPD results were scored based on the presence or absence of each of the 8 bands and then converted to computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of each band, respectively. Based on these results, a model DNA fingerprint and a computerized DNA fingerprint were constructed. In the constructed DNA fingerprint, each Porphyra line has its unique fingerprinting pattern and can be easily distinguished from each other. Later, a software, named as PhGI, was designed based on this DNA fingerprinting. It can be used in practical Porphyra line identification. 展开更多
关键词 computerIZED DNA fingerprinting RAPD PORPHYRA GERMPLASM IDENTIFICATION
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Peripancreatic collections in acute pancreatitis: Correlation between computerized tomography and operative fi ndings 被引量:5
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作者 Santhi Swaroop Vege Joel G Fletcher +1 位作者 Rupjyoti Talukdar Michael G Sarr 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第34期4291-4296,共6页
AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who u... AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who underwent operative intervention for severe acute pancreatitis were retrospectively studied. The collections were classified into (1) necrosis without frank pus; (2) necrosis with pus; and (3) fluid without necrosis. A blinded radiologist assessed the preoperative CTs of each patient for necrosis and peripancreatic fluid collections. Peripancreatic collections were described in terms of volume, location, number, heterogeneity, fluid attenuation, wall perceptibility, wall enhancement, presence of extraluminal gas, and vascular compromise.RESULTS: Fifty-four collections were identif ied at operation, of which 45 (83%) were identif ied on CECT. Of these, 25/26 (96%) had necrosis without pus, 16/19 (84%) had necrosis with pus, and 4/9 (44%) had fluid without necrosis. Among the study characteristics, fluid heterogeneity was seen in a greater proportion of collections in the group with necrosis and pus, compared to the other two groups (94% vs 48% and 25%, P = 0.002 and 0.003, respectively). Among the wall characteristics, irregularity was seen in a greater proportion of collections in the groups with necrosis with and without pus, when compared to the group with fluid without necrosis (88% and 71% vs 25%, P = 0.06 and P < 0.01, respectively). The combination of heterogeneity and presence of extraluminal gas had a specif icity and positive likelihood ratio of 92% and 5.9, respectively, in detecting pus. CONCLUSION: Most of the peripancreatic collections seen on CECT in patients with severe acute pancreatitis who require operative intervention contain necrotic tissue. CECT has a somewhat limited role in differentiating the different types of collections. 展开更多
关键词 Contrastenhanced computerized tomogra-phy CORRELATION Pancreatic necrosis PANCREATITIS Peripancreatic fluid collection Surgery
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Positron emission tomography/computerized tomography in the evaluation of primary non-Hodgkin's lymphoma of prostate 被引量:4
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作者 Bo Pan Jian-Kui Han +1 位作者 Shi-Cun Wang Ao Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第39期6699-6702,共4页
Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign pr... Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign prostatic hypertrophy was suspected at primary impression.Ultrasound revealed a hypoechoic lesion of the prostate.The total serum prostate-specific antigen was within normal range.Positron emission tomography/computerized tomography(PET/CT)showed a hypermetabolic prostatic lesion.Prostate biopsy was consistent with a non-germinal center diffuse large B cell lymphoma.There was complete remission of the prostatic lesion following six cycles of chemotherapy as shown on the second PET/CT imaging.18F-fluoro-deoxy glucose PET/CT is not only a complement to conventional imaging,but also plays a significant role in the diagnosis and evaluation of treatment response of prostatic lymphoma. 展开更多
关键词 Fluoro-Deoxy-Glucose Positron emission tomography/computerized tomography Non-Hodgkin’s LYMPHOMA PROSTATIC LYMPHOMA EVALUATION
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COMPUTERIZED SIMULATION OF MOLTEN SALT SOLUTION OF Li,KF,Cl SYSTEM BY MOLECULAR DYNAMIC METHOD 被引量:2
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作者 SHAO Jun Shanghai University of Science and Technology,Shanghai,ChinaXU Hua CHEN Nianyi Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,China SHAO Jun Associate Professor,Dept.of Chemistry,Shanghai University of Science and Technology,Shanghai 201800,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第10期221-225,共5页
The structure and properties of molten salt solution o J Li,K|F,Cl system have been investigedby computerized simulation of molecular dynamic method.The partial RDF,the partial molarenergy of mixing and the diffusion ... The structure and properties of molten salt solution o J Li,K|F,Cl system have been investigedby computerized simulation of molecular dynamic method.The partial RDF,the partial molarenergy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated.The results are in agreement with the experimental values.The regularities of the distributionof ions and mieroscopic holes are discussed based on the results of computerized simulation. 展开更多
关键词 ALKALI HALIDE MOLTEN salt MOLECULAR dynamic method computerIZED simulation
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The Clinical Application of Computerized Three-Dimensional Mimic Operation for Maxillofacial Bone Tumor 被引量:2
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作者 陶学金 殷孝蓉 +1 位作者 朱芳 陈卫民 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1999年第4期328-330,共3页
Facial bone, as the frame to support maxillofacial region and with several sinuses and cavities, is structurally complicated and the maxillofacial tumors,benign or malignant, in this region usually grows into the deep... Facial bone, as the frame to support maxillofacial region and with several sinuses and cavities, is structurally complicated and the maxillofacial tumors,benign or malignant, in this region usually grows into the deep tissues, sinus-cav-ities and orbit and destroys the bone. In this study, the maxillofacial tumors were subjected to a mimic operation on a computer following CT scanning and 3-dimen-sional reconstruction. The data similar to those of real operation were obtained,which could be used for developing operative plans. As compared with data on the basis of conditions in the real operation, computerized mimic operation reflected the real conditions during operation. Computerized mimic operation is valuable for the preoperative planning and the prediction of probable intraoperative events. 展开更多
关键词 maxillofacia TUMOR computerIZED MIMIC operation COMPUTED TOMOGRAPHY
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Effects of Irregular Respiratory Motion on the Positioning Accuracy of Moving Target with Free Breathing Cone-Beam Computerized Tomography 被引量:1
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作者 Xiang Li Tianfang Li +9 位作者 Ellen Yorke Gig Mageras Xiaoli Tang Maria Chan Weijun Xiong Marsha Reyngold Richard Gewanter Abraham Wu John Cuaron Margie Hunt 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第2期173-183,共11页
For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT ... For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT (FBCBCT) before treatment. This method can be highly accurate if the respiratory motion of the patient is stable. However, a patient’s breathing pattern is often irregular. The purpose of this study is to investigate the effects of irregular respiration on positioning accuracy for a moving target aligned with FBCBCT. Nine patients’ respiratory motion curves were selected to drive a Quasar motion phantom with one embedded cubic and two spherical targets. A 4DCT of the phantom was acquired on a CT scanner (Philips Brilliance 16) equipped with a Varian RPM system. The phase binned 4DCT images and the corresponding MIP and AIP images were transferred into Eclipse for analysis. FBCBCTs of the phantom driven by the same respiratory curves were also acquired on a Varian TrueBeam and fused such that both CBCT and MIP/AIP images share the same target zero positions. The sphere and cube volumes and centroid differences (alignment error) determined by MIP, AIP and FBCBCT images were calculated, respectively. Compared to the volume determined by MIP, the volumes of the cube, large sphere, and small sphere in AIP and FBCBCT images were smaller. The alignment errors for the cube, large sphere and small sphere with center to center matches between MIP and FBCBCT were 2.5 ± 1.8 mm, 2.4 ± 2.1 mm, and 3.8 ± 2.8 mm, and the alignment errors between AIP and FBCBCT were 0.5 ± 1.1 mm, 0.3 ± 0.8 mm, and 1.8 ± 2.0 mm, respectively. AIP images appear to be superior reference images to MIP images. However, irregular respiratory pattern could compromise the positioning accuracy, especially for smaller targets. 展开更多
关键词 CONE Beam computerIZED TOMOGRAPHY RESPIRATORY Motion Effect
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AN ANALYSIS OF ACOUSTIC CHARACTERISTICS OFCLEFT PALATE SPEECH WITH COMPUTERIZED SPEECH SIGNAL PROCESSING SYSTEM 被引量:1
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作者 李锦峰 刘建华 《Journal of Pharmaceutical Analysis》 CAS 1996年第2期162-165,共4页
ANANALYSISOFACOUSTICCHARACTERISTICSOFCLEFTPALATESPEECHWITHCOMPUTERIZEDSPEECHSIGNALPROCESSINGSYSTEMLiJinfeng;... ANANALYSISOFACOUSTICCHARACTERISTICSOFCLEFTPALATESPEECHWITHCOMPUTERIZEDSPEECHSIGNALPROCESSINGSYSTEMLiJinfeng;LiuJianhua;(Depar?.. 展开更多
关键词 cleft PALATE SPEECH the Chinese vowels the FORMANT pattern the SPEECH articulation computerIZED SPEECH singnal PROCESSING SYSTEM
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Changes in reaction time, coefficient of variance of reaction time, and autonomic nerve function in the mental fatigue state caused by long-term computerized Kraepelin test workload in healthy volunteers 被引量:1
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作者 Daisuke Kuratsune Seiki Tajima +10 位作者 Junichi Koizumi Kouzi Yamaguti Tetsuya Sasabe Kei Mizuno Masaaki Tanaka Naoko Okawa Hideki Mito Hirokazu Tsubone Yasuyoshi Watanabe Masayasu Inoue Hirohiko Kuratsune 《World Journal of Neuroscience》 2012年第2期113-118,共6页
Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we sho... Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we show that the decrease of working efficiency and sympathetic hyperactivity are associated with mental fatigue state caused by prolonged mental workload. Recently we made a new mental fatigue model of healthy volunteers caused by long-term computerized Kraepelin test (CKT) workload. CKT is our new software for automatically checking the calculation capability, with which it is easy to determine the reaction time (RT), coefficient of variance of reaction time (CV), and accuracy of the answers (AC) during tasks. We put 24 healthy volunteers into the fatigue state by subjecting them to 120 minutes’ CKT workload, and then studied the changes in fatigue sensation, RT, CV, and AC before and after the CKT workload. The fatigue sensation, RT, and CV were clearly increased by the fatigue-inducing task and recovered during the resting period. We also studied the changes in autonomic nerve activity by using heart rate variability analysis. The low/high frequency component ratio (LF/HF) was signifi-cantly increased by the fatigue-inducing task and decreased by resting, suggesting that mental stress causes a relatively sympathetic nerve activity-dominant state. Therefore, our new fatigue model involving a long-term CKT workload is a good mental fatigue model to provide much information about the fatigue state simultane-ously, and the increase of RT, CV, and proportion of sympathetic activity (LF/HF) are associated with mental fatigue state. These might be useful objective biomarkers or evaluating a mental fatigue state. 展开更多
关键词 Fatigue computerIZED Kraepelin Test Reaction Time Accuracy of the ANSWERS AUTONOMIC NERVE Activity
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The Differences of Interstitial Lung Diseases in High-Resolution Computerized Tomography and Pulmonary Function Test among Different Connective Tissue Diseases, and the Correlated Factors 被引量:1
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作者 Zhen Jiang Wenyou Pan +1 位作者 Jinhui Tao Xiangpei Li 《Open Journal of Rheumatology and Autoimmune Diseases》 2018年第2期53-65,共13页
Objective. To study the difference of interstitial lung diseases (ILDs) in high-resolution computerized tomography and pulmonary function test among different connective tissue diseases (CTDs). Methods. 209 patients w... Objective. To study the difference of interstitial lung diseases (ILDs) in high-resolution computerized tomography and pulmonary function test among different connective tissue diseases (CTDs). Methods. 209 patients with different CTDs were recruited and underwent lung HRCT and PFT. Eerythrocyte sedimentation rate (ESR), C-reactive protein (CRP), serum ferritin (SF), anti-SSA, and so on were tested. Based on HRCT, a patient was classified into ILD group (CTD+ILD) or non-ILD group (CTD-ILD). HRCT, PFT, and laboratory markers were compared according to CTDs and CTD-associated ILDs. Results. The incidences of ILD were 79.6%, 82.0%, 89.7%, and 97.1% respectively for Rheumatoid arthritis (RA), primary Sjogren’s symptom (pSS), dermatomyositis/polymyositis (DM/PM), and systemic sclerosis (SSc) groups. RA and pSS patients exhibited more nodules, patching, ground-glass opacity, and cord shadow foci in HRCT, DM/PM and SSc patients exhibited more reticular opacity and honeycombing foci. RA and pSS patients exhibited more obstructive ventilatory disorder, small airway dysfunction and emphysema in PFT, and DM/PM and SSc patients exhibited more restrictive ventilatory disorder, mixed ventilatory disorder. ESR, CRP and SF were significantly higher in total CTD+ILD group than in total CTD-ILD group (P = 0.047, 0.006, 0.004, respectively), and higher in different CTD+ ILD groups than in comparable CTD-ILD groups (P = 0.049, 0.048, and 0.023, pSS+ILD, SSc+ILD and RA+ILD compared to pSS-ILD, SSc-ILD and RA-ILD, respectively for ESR, CRP, SF). The positive rate of anti-SSA was significantly higher in DM/PM+ILD group than in DM/PM-ILD group (P = 0.025). Conclusions. The manifestations and incidences of ILDs differ among different CTDs in HRCT and PFT, and inflammation and anti-SSA are positively correlated with ILDs in different CTDs, which provide important evidences for judging disease condition and prognosis. 展开更多
关键词 CONNECTIVE Tissue Diseases INTERSTITIAL lung Disease HIGH-RESOLUTION computerIZED Tomography PULMONARY Function Test Inflammation
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Computer-Aided Solution to the Vibrational Effect of Instabilities in Gas Turbine Compressors 被引量:1
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作者 Ezenwa Alfred Ogbonnaya Hyginus Ubabuike Ugwu Charles Agbeju Nimibofa Johnson 《Engineering(科研)》 2010年第8期658-664,共7页
Surge and stall are the two main types of instabilities that often occur on the compressor system of gas turbines. The effect of this instability often leads to excessive vibration due to the back pressure imposed to ... Surge and stall are the two main types of instabilities that often occur on the compressor system of gas turbines. The effect of this instability often leads to excessive vibration due to the back pressure imposed to the system by this phenomenon. In this work, fouling was observed as the major cause of the compressor instability. A step to analyze how this phenomenon can be controlled with the continuous examination of the vibration amplitude using a computer approach led to the execution of this work. The forces resulting to vibration in the system is usually external to it. This external force is aerodynamic and the effect was modeled using force damped vibration analysis. A gas turbine plant on industrial duty for electricity generation was used to actualize this research. The data for amplitude of vibration varied between -15 and 15 mm/s while the given mass flow rate and pressure ratio were determined as falling between 6.1 to 6.8 kg/s and 9.3 to 9.6 respectively. A computer program named VICOMS written in C++ programming language was developed. The results show that the machine should not be run beyond 14.0 mm vibration amplitude in order to avoid surge, stall and other flow-induced catastrophic breakdown. 展开更多
关键词 computerIZED Solution INSTABILITIES VIBRATION Gas TURBINE Compressors OPERATIONAL Limits
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Computerized simulative method of three dimensions outline of log
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作者 王阿川 金维洙 +3 位作者 韩玉杰 蔡立新 杨家武 贾娜 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期127-128,共2页
Log centering accuracy depends on the computerized simulative level of its three-dimension outline.In this paper, the basic methods about distinguishing three dimensions outline of log by means of computerized simulat... Log centering accuracy depends on the computerized simulative level of its three-dimension outline.In this paper, the basic methods about distinguishing three dimensions outline of log by means of computerized simulation are discussed. It is suggested that straight lines or certain curves should be introduced to connect the separated points along some log generatrices. Taking bent logs for example verify the accuracy of computerized simulative method. 展开更多
关键词 computerIZED SIMULATION THREE DIMENSIONS OUTLINE LOG
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Computerized Simulation of Structure of NaAIO_2 Melt
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作者 Chi XU Ming LI Nianyi CHEN Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,200050,China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1993年第1期65-67,共3页
The structure of NaAlO<sub>2</sub> melt has been studied by computerized simulation using Monte Carlomethod.The radial distribution functions and Local structure of this melt are calculated.It has beenfoun... The structure of NaAlO<sub>2</sub> melt has been studied by computerized simulation using Monte Carlomethod.The radial distribution functions and Local structure of this melt are calculated.It has beenfound that NaAlO<sub>2</sub> melt contains ionic clusters formed by corner-sharing AlO<sub>4</sub> tetrahedra,sodiumions and xNa<sup>+</sup>.yO<sup>2-</sup> ionic clusters. 展开更多
关键词 computerIZED SIMULATION NaAlO2 MELT MONTE Carlo method
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Designing of A Computerized Cognitive Adaptive Testing Model
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作者 He Lianzhen 《现代外语》 CSSCI 北大核心 1999年第2期169-171,共3页
Therecouldbenoscienceasweknowitwithoutmeasurement.Testing,includingallformsoflanguagetestingandpsychometricsitself,isoneformofmeasurement.Alanguagetestmaybedefinedasaprocedureforelicitinglanguageperformanceandaprocedu... Therecouldbenoscienceasweknowitwithoutmeasurement.Testing,includingallformsoflanguagetestingandpsychometricsitself,isoneformofmeasurement.Alanguagetestmaybedefinedasaprocedureforelicitinglanguageperformanceandaprocedureforassessingthatperformance.How... 展开更多
关键词 Item Response Theory (IRT) computerIZED ADAPTIVE TESTING (CAT ) COGNITIVE PSYCHOLOGY (CP) computerIZED COGNITIVE ADAPTIVE Testing(CCAT)
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COMPUTERIZED PREDICTION OF INTERACTION PARAMETERSAND PHASE DIAGRAMS OF CONTINUOUS SOLID SOLUTION OFBINARY ALLOY SYSTEMS
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作者 J. Guo (Department of Physics, Guangxi University, Nanning 530004, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第3期216-220,共5页
The artificial neural network method has been applied to the relationship between the atomic parameters and intemction packeters of binary alloy Phases, and the principle of thermodynamics in combination with artifici... The artificial neural network method has been applied to the relationship between the atomic parameters and intemction packeters of binary alloy Phases, and the principle of thermodynamics in combination with artificial neural network method has been used for the computerized phase diagrams of continuous solid solution of bigamy alloy systems. The computerized phase diagrams well agree with the real phase diagmms. 展开更多
关键词 antificial NEURAL network INTERACTION PARAMETER computerIZED phase DIAGRAM
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A computerized resolution visual acuity test in preschool and school age children
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作者 Ying-Yan Qin Zhen-Zhen Liu +5 位作者 Li-Yuan Zhu Xuan Bao Fu-Rong Luo Yi-Zhi Liu Young Tsau Ming-Xing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期284-291,共8页
●AIM:To develop a novel approach called the Autoacuity Tester,and to evaluate its validity,especially the sensitivity and specificity for detecting amblyopia.●METHODS:Children aged from 3 to 12 y(n=552)were enrolled... ●AIM:To develop a novel approach called the Autoacuity Tester,and to evaluate its validity,especially the sensitivity and specificity for detecting amblyopia.●METHODS:Children aged from 3 to 12 y(n=552)were enrolled in the study.The validity of the Autoacuity Tester was evaluated by comparing it to the Tumbling E Early Treatment Diabetic Retinopathy Study(ETDRS)acuity chart for school age children,and Lea Symbols and Teller acuity card(TAC)for preschool children.The repeatability was assessed by coefficient of repeatability(COR).The sensitivity and specificity for detecting amblyopia were calculated.●RESULTS:The mean difference(95%limits of agreement)between the Autoacuity Tester and the ETDRS tests were-0.03(-0.24,0.19)logMAR for the school age group.In preschool children,the mean difference was 0.04(-0.14,0.21)logMAR between the Autoacuity Tester and the TAC and 0.00(-0.17,0.18)logMAR between the Autoacuity Tester and the Lea Symbols.For the school age group,the COR was 0.20 logMAR for the Autoacuity Tester and 0.18 logMAR for the ETDRS.For the preschool group,the COR was 0.13 logMAR for the Autoacuity Tester and 0.21 logMAR for TAC.The Autoacuity Tester(88%)is more sensitive than TAC(72%)in detecting amblyopia(P=0.04),while had similar specificity(92%vs 90%,P=0.20).●CONCLUSION:The Autoacuity Tester provides a reliable alternative for assessing visual acuity,and offers advantage of higher testability and repeatability for preschool children. 展开更多
关键词 visual ACUITY TEST computerIZED CHILDREN sensitivity AMBLYOPIA
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