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Artificial intelligence models based on non-contrast chest CT for measuring bone mineral density
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作者 DUAN Wei YANG Guoqing +6 位作者 LI Yang SHI Feng YANG Lian XIONG Xin CHEN Bei LI Yong FU Quanshui 《中国医学影像技术》 CSCD 北大核心 2024年第8期1231-1235,共5页
Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quan... Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quantitative CT(QCT)BMD examination were retrospectively enrolled and divided into training set(n=304)and test set(n=76)at a ratio of 8∶2.The mean BMD of L1—L3 vertebrae were measured based on QCT.Spongy bones of T5—T10 vertebrae were segmented as ROI,radiomics(Rad)features were extracted,and machine learning(ML),Rad and deep learning(DL)models were constructed for classification of osteoporosis(OP)and evaluating BMD,respectively.Receiver operating characteristic curves were drawn,and area under the curves(AUC)were calculated to evaluate the efficacy of each model for classification of OP.Bland-Altman analysis and Pearson correlation analysis were performed to explore the consistency and correlation of each model with QCT for measuring BMD.Results Among ML and Rad models,ML Bagging-OP and Rad Bagging-OP had the best performances for classification of OP.In test set,AUC of ML Bagging-OP,Rad Bagging-OP and DL OP for classification of OP was 0.943,0.944 and 0.947,respectively,with no significant difference(all P>0.05).BMD obtained with all the above models had good consistency with those measured with QCT(most of the differences were within the range of Ax-G±1.96 s),which were highly positively correlated(r=0.910—0.974,all P<0.001).Conclusion AI models based on non-contrast chest CT had high efficacy for classification of OP,and good consistency of BMD measurements were found between AI models and QCT. 展开更多
关键词 OSTEOPOROSIS bone density tomography X-ray computed artificial intelligence
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章怀太子墓壁画《仪卫图》与“画圣”吴道子
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作者 石瑜 《唐都学刊》 2009年第1期52-54,共3页
章怀太子墓室壁画是唐人物画中的最具代表性作品之一。特别是《仪卫图》的绘画风格和绘画技法,有"吴带当风"独特性。笔者认为,有很多历史线索和证据都在向我们表明,该作品的作者很有可能就是我国唐朝最著名的"画圣"... 章怀太子墓室壁画是唐人物画中的最具代表性作品之一。特别是《仪卫图》的绘画风格和绘画技法,有"吴带当风"独特性。笔者认为,有很多历史线索和证据都在向我们表明,该作品的作者很有可能就是我国唐朝最著名的"画圣"吴道子。 展开更多
关键词 李贤墓室壁画 吴道子 “疏体” “密体” 新风格 技法
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Fabrication and anti-corrosion performance of superhydrophobic silane film on sintered NdFeB
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作者 Wen-tao JU Li JIANG +6 位作者 Yan-xia LIANG Shu-ting XU Ke WANG Yu-meng YANG Ben-feng ZHU Guo-ying WEI Zhao ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2928-2942,共15页
An eco-friendly superhydrophobic protective film(DTMS/TEOS silane film)was fabricated on sintered NdFeB substrate through the utilization of electrochemically assisted deposition technology.The structure,properties,an... An eco-friendly superhydrophobic protective film(DTMS/TEOS silane film)was fabricated on sintered NdFeB substrate through the utilization of electrochemically assisted deposition technology.The structure,properties,and film-forming mechanism of dodecyltrime-thoxysilane(DTMS)/tetraethoxysilane(TEOS)silane films were comprehensively analyzed using Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),potentiodynamic polarization curves and electrochemical impedance spectroscopy(EIS).Based on the test results,it can be determined that this film has a superhydrophobic property with a hydrophobicity angle of 152°.This special property can be attributed to the long alkyl chains in the DTMS molecule,the rough morphology,and the low surface energy of the DTMS/TEOS silane film.The surface of sintered NdFeB is coated with a layered three-dimensional network silane film that forms through the condensation of silanol substances.This film provides excellent corrosion resistance to the sintered NdFeB substrate,reducing its corrosion current density to 2.02×10~(-6)A/cm~2.Moreover,the impact of film on the magnetic characteristics of sintered NdFeB was assessed and found to be minimal. 展开更多
关键词 NdFeB magnet silane film corrosion resistance SUPERHYDROPHOBICITY electrochemically assisted deposition
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Structure and corrosion resistance of modified micro-arc oxidation coating on AZ31B magnesium alloy 被引量:2
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作者 崔学军 杨瑞嵩 +2 位作者 刘春海 余祖孝 林修洲 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期814-821,共8页
A hydrophobic surface was fabricated on a micro-arc oxidation (MAO) treated AZ31 Mg alloys via surface modification with myristic acid. The effects of modification time on the wettability of the coatings were investig... A hydrophobic surface was fabricated on a micro-arc oxidation (MAO) treated AZ31 Mg alloys via surface modification with myristic acid. The effects of modification time on the wettability of the coatings were investigated using the contact angle measuring device. The surface morphologies and structure of the coatings were evaluated using SEM, XRD and FT-IR. The corrosion resistance was investigated by potentiodynamic polarization curves and long-term immersion test. The results showed that the water contact angle (CA) increases gradually with modification time from 0 to 5 h, the highest CA reaches 138° after being modified for 5 h, and the number and size of the micro pores are decreased. The modification method hardly alters crystalline structure of the MAO coating, but improves the corrosion resistance based on the much positive potential and low current density. Moreover, the corrosion resistance and hydrophobicity can be enhanced with increasing the alkyl chain. The wetting and spreading for the alkylcarboxylate with low surface energy become easier on the micro-porous surface, and alkylcarboxylate monolayer will be formed through bidentate bonding, which changes the surface micropores to a sealing or semi-sealing structure and makes the MAO coating dense and hydrophobic. All the results demonstrate that the modification process improves the corrosion protection ability of the MAO coating on AZ31B Mg alloy. 展开更多
关键词 magnesium alloys micro-arc oxidation plasma electrolytic oxidation HYDROPHOBICITY myristic acid corrosion resistance
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The Sequestered Actin Was Bound to Non-actin Protein(s) in the ATP-depleted Rabbit Proximal Tubules
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作者 顾洛 杜军 +3 位作者 戈应滨 范乐明 陈琪 陈进 《Journal of Nanjing Medical University》 2003年第6期270-276,共7页
Objective: To demonstrate whether the actin breakdown fromactin-cytoskele-ton in microvilli was bound to any non-actin protein ( s ) in 'ATP-depleted rabbitproximal tubules (PT). Methods: By using DTSSP to crossli... Objective: To demonstrate whether the actin breakdown fromactin-cytoskele-ton in microvilli was bound to any non-actin protein ( s ) in 'ATP-depleted rabbitproximal tubules (PT). Methods: By using DTSSP to crosslink actin and non-actin protein (s) ininsoluble fraction of ATP-depleted PT, the crosslinked protein complexes were analysed bytwo-dimensional electrophoresis and western blotting. Results: Analysis of the crosslinked actincomplexes revealed one complex that contained actin and non-actin protein. Villin was not detected.Conclusion: The results strongly suggested that some of the sequestered actin was directly bound tonon-actin protein (s) other than was co-precipitated with villin or the nuclei as hydrophobic actinhomopolymers. 展开更多
关键词 ACTIN VILLIN ISCHEMIA MICROVILLI kidney
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Association of CA Repeat Polymorphism in Estrogen Receptor β Gene with Postmenopausal Osteoporosis in Chinese
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作者 耿力 姚珍薇 +3 位作者 杨洪昌 骆建云 韩力力 卢起 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第10期868-876,共9页
Postmenopausal osteoporosis (PMO) is considered a polygenic disease. The estrogen receptor β (ESR2) gene is a candidate mediating the genetic influence on bone mass and the risk of osteoporosis. The aim of this s... Postmenopausal osteoporosis (PMO) is considered a polygenic disease. The estrogen receptor β (ESR2) gene is a candidate mediating the genetic influence on bone mass and the risk of osteoporosis. The aim of this study is to investigate the association of a cytosine-adenine (CA) repeat polymorphism in the fifth intron of the ESR2 gene with PMO in Chinese Han population. The CA repeat polymorphism was genotyped in a case-control study, involving 78 femoral neck PMO patients vs. 122 controls and 108 lumbar spine (L2-4) PMO patients vs. 92 controls. The (CA)n〈22 and (CA)n≥22 alleles were designated short (S) and long (L), respectively. ESR2 genotype was categorically defined as SS (2 S alleles), SL (having the mixed S and L alleles), and LL (2 L alleles). At both the femoral neck and the L2-4 region, LL genotype and L allele frequencies of the PMO group were significantly higher than those of the control group (P〈0.01). The subjects with the SL, the LL, and the combined SL and LL genotype had a significant increased risk of PMO when compared with those with the SS genotype (P〈0.05). After adjustments for age, years since menopause, menopausal age, and body mass index, logistic regression analysis showed that the subjects with the combined SL and LL genotype had increased risk of PMO when compared with those with the SS genotype both at the femoral neck (adjusted OR 4.923, 95% CI 1.986-12.203 , P=0.001) and the L2-4 (adjusted OR 2.267, 95% CI 1.121-4.598, P=0.023). This extensive association study has identified the ESR2 CA repeat polymorphism to be independently associated with PMO at the femoral neck and the L2-4 in Chinese Han population. The data also suggested that the presence of the L allele may dominantly increase the risk of PMO at the two regions. 展开更多
关键词 OSTEOPOROSIS POSTMENOPAUSAL estrogen receptor β (ESR2) POLYMORPHISMS bone mineral density
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The Effect of Hydrophobic Modification of Zeolites on CO2 Absorption Enhancement 被引量:5
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作者 卢素敏 马友光 +2 位作者 朱春英 沈树华 何清 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期36-41,共6页
Two methods of the modification of zeolite were employed: framework element modification and surface coating, and the influence of the zeolites before and after modification on the CO2 absorption was investigated. It... Two methods of the modification of zeolite were employed: framework element modification and surface coating, and the influence of the zeolites before and after modification on the CO2 absorption was investigated. It was found that although hydrophobicity of zeolite could be obtained by means of the surficial organic coating in the method of surface coating _mod!fication, partial channel of zeolite would be plugged, as a result, leading to the surface area reducing greatly. Distinctively, the framework element modification method could maintain not only complete lattice structure and adsorption capability of zeolite, but would also obtain a good hydrophobic property. Consequently, significant enhancement on gas absorption by this modified zeolite was achieved and up to a maximum enhancement factor of 2.62. This shows that the solid particles with good enhancement role to gas absorption need not only good adsorptive capability but also certain hydrophobicity. An unsteady heterogeneous model was employed to predict enhancement factor and the calculated results agree well with the experimental data. 展开更多
关键词 ZEOLITE MODIFICATION enhancement of gas absorption HYDROPHOBICITY
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Compressive and Rarefactive Waves in Dust Plasma with Non-thermal Ions 被引量:5
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作者 DUAN Wen-Shan WANG Hong-Yan John Parkes 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1112-1116,共5页
The governing equation of the dust fluid with non-thermal ions and variable dust charge on dust particles in hot dust plasmas is obtained. Both the compressive and rarefactive waves in this system are investigated. Th... The governing equation of the dust fluid with non-thermal ions and variable dust charge on dust particles in hot dust plasmas is obtained. Both the compressive and rarefactive waves in this system are investigated. They can be determined by plasma parameters including the temperatures of (lust fluid, ions and electrons, as well as the non-thermal parameter of ions, and the number densities of the dust particles, the ions and the electrons, etc. 展开更多
关键词 compressive wave rarefactive wave SOLITON
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Prevalence of IgA-antiendomysial antibody in a patient cohort with idiopathic low bone mineral density 被引量:1
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作者 T Karakan O Ozyemisci-Taskiran +2 位作者 Z Gunendi F Atalay C Tuncer 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第21期2978-2982,共5页
AIM:To investigate the frequency of serum IgA-antiendomysial antibody positivity in patients with low bone mineral density and to assess the risk group for screening of celiac disease. METHODS:One hundred and thirty-f... AIM:To investigate the frequency of serum IgA-antiendomysial antibody positivity in patients with low bone mineral density and to assess the risk group for screening of celiac disease. METHODS:One hundred and thirty-five patients (14 male,121 female) with idiopathic low bone mineral density were evaluated. The median age was 57.2 years (24-81). Antiendomysial antibody was determined by the immunofluorescence method using a commercial kit (INOVA Diagnostics Inc.,CA,USA),which employs a 5 μm thin cryostat section of monkey esophagus as a substrate. RESULTS:Of the 135 patients evaluated,13 were found to have positive IgA antiendomysial antibody test (9.6%) response. None of the patients had IgA deficiency. Endoscopic appearance and histological examination were normal in all of these patients. Seropositive patients had significantly lower age (48.9 ± 4.3 vs 59.2 ± 6.2,P < 0.05),higher ratio of male gender (61.5% vs 4.9%,P < 0.01) and pre-menopausal status (8.7% vs 1.3%,P < 0.01). Lumbar spine and femoral neck z-scores,but not t-scores were significantly lower in seropositive patients. Seropositive patients had lower serum 25 (OH) vitamin D,calcium and higher serum parathormone levels than seronegative patients. CONCLUSION:The screening of celiac disease in idiopathic osteoporosis should be restricted to patients without classical risk factors (younger,pre-menopausal,male gender) for osteoporosis. Bone mineral density measurements using z-scores should be considered for identifying risk groups for celiac disease. 展开更多
关键词 Antiendomysial antibodies Celiac disease OSTEOPOROSIS
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Investigation on Preparation and Anti-icing Performance of Superhydrophobic Surface on Aluminum Conductor 被引量:4
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作者 Hai-yun Jin Shi-chao Nie +2 位作者 Zhi-wei Li Cheng Tong Ke-jing Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第2期216-222,246,共8页
Aluminum is widely used in transmission lines, and the accumulation of ice on aluminum conductor may inflict serious damage such as tower collapse and power failure. In this study, super-hydrophobic surface (SHS) on... Aluminum is widely used in transmission lines, and the accumulation of ice on aluminum conductor may inflict serious damage such as tower collapse and power failure. In this study, super-hydrophobic surface (SHS) on alurninurn conductor with rnicro-nanostructure was fabricated using the preferential etching principle of crystal defects. The surface rnicrostructure and wettability were investigated by scanning electron microscope and contact angle measurement, respectively. The icing progress was observed with a self-made icing experiment platform at different environment temperature. The results showed that, due to jumping and rolling down of coalesced droplets from SHS of aluminum conductor at low temperature, the formation of icing on SHS could be delayed. Dynamic icing experiment indicated that SHS on aluminum conductor could restrain the formation of icing in certain temperature range, but could not exert influence on the accumulation of icing. This study offers new insight into understanding the anti-icing performance of actual aluminum conductor. 展开更多
关键词 SUPER-HYDROPHOBIC Aluminum conductor Crystal defects Self-propelledjumping ANTI-ICING
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Simulation of Vapor Flows Between Two Closed Surfaces of Evaporation and Condensation at High Vacuum
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作者 张旭斌 许春建 周明 《Transactions of Tianjin University》 EI CAS 2003年第2期101-108,共8页
The steady multi component vapor flows between two closed surfaces of evaporation and condensation are investigated numerically by the nonlinear Bhatnagar Gross Krook equation. The mathematical model will make it poss... The steady multi component vapor flows between two closed surfaces of evaporation and condensation are investigated numerically by the nonlinear Bhatnagar Gross Krook equation. The mathematical model will make it possible to determine the profiles of the process variables between two surfaces of evaporation and condensation if the conditions of evaporation and condensation surfaces are taken into consideration. It is used to simulate the vapor behaviors of the pure dibutylphthalate and the ethylhexyl phthalate ethylhexyl sebacate mixture. The effects of the liquid composition of the evaporation surface, the evaporation temperature, the condensation temperature and the distance between evaporation and condensation surfaces on the evaporation efficiency and separation factor are discussed. 展开更多
关键词 Bhatnagar Gross Krook equation numerical simulation rarefied gas SEPARATION
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Multiple wave prediction and suppression based on LO-norm sparsity constraint
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作者 Lv Xiao-Chun Zou Ming-Jun +1 位作者 Sun Chang-Xin Chen Shi-Zhong 《Applied Geophysics》 SCIE CSCD 2019年第4期483-490,561,共9页
Multiple wave is one of the important factors affecting the signal-to-noise ratio of marine seismic data.The model-driven-method(MDM)can effectively predict and suppress water-related multiple waves,while the quality ... Multiple wave is one of the important factors affecting the signal-to-noise ratio of marine seismic data.The model-driven-method(MDM)can effectively predict and suppress water-related multiple waves,while the quality of the multiple wave contribution gathers(MCG)can affect the prediction accuracy of multiple waves.Based on the compressed sensing framework,this study used the sparse constraint under LO norm to optimize MCG,which can not only reduce the false in the prediction and improve the image accuracy,but also saves computing time.At the same time,the MDM-type method for multiple wave suppression can be improved.The unified prediction of multiple types of water-related multiple waves weakens the dependence of conventional MDM on the adaptive subtraction process in suppressing water-related multiple waves,improves the stability of the method,and simultaneously,reduces the computational load.Finally,both theoretical model and practical data prove the effectiveness of the present method. 展开更多
关键词 Compressed sensing sparsity constraint water-related multiples multiple prediction
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The Effect of Age and Markers of Obesity on Bone Density in Iraqi Postmenopausal Women
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作者 Hedef Dhafir EL-Yassin Rana Faisal Hammadi Nazar Abdulateef 《Journal of Life Sciences》 2014年第1期15-21,共7页
Osteoporosis is a disease characterized by a low bone mineral density and structural deterioration of bone tissue. Leptin is considered to play a role in the maintenance of energy balance and body weight. Weight and b... Osteoporosis is a disease characterized by a low bone mineral density and structural deterioration of bone tissue. Leptin is considered to play a role in the maintenance of energy balance and body weight. Weight and body mass index are associated with low bone mineral density with high serum leptin concentration in older women. The study is designed to elucidate the impact of age and BMI (Body Mass Index) on osteoporotic patients (Iraqi postmenopausal women) and the functional role of leptin in those patients. A total of 72 patients divided into three groups according to BMI and two groups according to age: BMD (bone mineral density), T-score and serum leptin concentration increased as BMI increased, while with increased age, BMD and T-score deceased and serum leptin concentration increased. There is a significant difference of BMD and T-score in BMI (25-30) group and BMI (〉 30) group from that in BMI (〈 25) group. In conclusions: Both age and BMI have an impact on osteoporosis although age shows more impact on the severity of the disease than does BMI. Studying the direct impact of leptin on BMD may open the way in using new methods in treating and preventing the osteoporosis in patients with risk factors. 展开更多
关键词 OSTEOPOROSIS LEPTIN OBESITY BMD BMI.
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Genetic Characterization of Four Strains Borrelia Burgdorferi Isolated in China
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作者 曾霞 王树声 +2 位作者 张涛 毕胜利 周永东 《Journal of Microbiology and Immunology》 2004年第1期6-9,共4页
To study the genetic characterization of four strains of Borrelia burgdorferi isolated in China. PCR technique was used to amplify the 5S-23S rRNA intergenic spacer DNA from the whole cellular DNA of isolated GXLD-4, ... To study the genetic characterization of four strains of Borrelia burgdorferi isolated in China. PCR technique was used to amplify the 5S-23S rRNA intergenic spacer DNA from the whole cellular DNA of isolated GXLD-4, 9, 18 and Chang 14, and then the amplified products were cloned into plasmid pGEM-T Easy and sequenced. It was found that the 5S-23S rRNA intergenic spacer DNA of the four isolates was 242?bp, revealing the nucleotide sequence identity of more than 99%. The four isolates had higher sequence identify with Borrelia valaisiana than with other genetic groups. These four isolates most likely belong to Borrelia valaisiana genomic group. 展开更多
关键词 Borrelia burgdorferi The 5S-23S rRNA intergenic spacer DNA CLONING Sequence analysis
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Anti⁃icing/De⁃icing Mechanism and Application Progress of Bio⁃inspired Surface for Aircraft 被引量:5
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作者 ZHU Yantong WANG Zelinlan +3 位作者 LIU Xiaolin ZHAO Zehui YAN Yuying CHEN Huawei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第5期541-560,共20页
Icing on the surface of aircraft will not only aggravate its quality and affect flight control,but even cause safety accidents,which is one of the important factors restricting all-weather flight.Bio-inspired anti-ici... Icing on the surface of aircraft will not only aggravate its quality and affect flight control,but even cause safety accidents,which is one of the important factors restricting all-weather flight.Bio-inspired anti-icing surfaces have gained great attention recently due to their low-hysteresis,non-stick properties,slow nucleation rate and low ice adhesion strength.These bio-inspired anti-icing surfaces,such as superhydrophobic surfaces,slippery liquid-infused porous surfaces and quasi-liquid film surfaces,have realized excellent anti-icing performance at various stages of icing.However,for harsh environment,there are still many problems and challenges.From the perspective of bioinspiration,the mechanism of icing nucleation,liquid bounce and ice adhesion has been reviewed together with the application progress and bottleneck issues about anti-icing in view of the process of icing.Subsequently,the reliability and development prospect of active,passive and active-passive integrated anti-icing technology are discussed,respectively. 展开更多
关键词 mechanical manufacturing and automation anti-icing of aircraft superhydrophobic surface slippery liquid-infused porous surface electrothermal coating
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Lyme Disease in Iraq: First Detection of IgM Antibodies to Borrelia burgdorferi in Human Sera
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作者 Khalis A. Hamad Ameen Basima A. Abdullah Riyad A. Abdul-Razaq 《Journal of Life Sciences》 2013年第11期1143-1146,共4页
The sera of 180 human samples were tested for the presence of antibodies against Borrelia burgdorferi using the ELISA (enzyme-linked immunosorbent assay) technique. Out of 180 sero-samples, 46 (25.55%) were positi... The sera of 180 human samples were tested for the presence of antibodies against Borrelia burgdorferi using the ELISA (enzyme-linked immunosorbent assay) technique. Out of 180 sero-samples, 46 (25.55%) were positive. Females of the age range 18-35 years had the highest rate of sero-positive samples 14 (38.88%), while the highest percentage of sero-negative samples was found in males of the age range 50-80 years. The other sero-positive samples were: 6 (26.08%), 6 (25%) and 3 (11.53%) in males of ages between 18-35, 35-50 and 50-80 years, respectively, and 11 (29.72%) and 6 (17.64%) in females in the age ranges 35-50 and 50-80 years, respectively. The mean concentration of Anti- B. burgdorferi antibody was higher (16.7 U/mL) when compared with mean concentration of normal value (5.5 U/mL), P 〈 0.001. 展开更多
关键词 Borrelia burgdorferi IgM antibodies Erbil Iraq ELISA
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Study on the Surface Modification of Hydrophobic Polyacrylate Intraocular Lens 被引量:2
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作者 TANG Hui-qin WANG Gui-qin GU Han-qing 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第1期29-36,共8页
In this study, the polyacrylate intraocularr lens is irradiated by argon ion which can produce free radicals. In order to obtain better hydrophilic and lower platelets adhesion, monomer vinyl pyrrolidone (NVP) is graf... In this study, the polyacrylate intraocularr lens is irradiated by argon ion which can produce free radicals. In order to obtain better hydrophilic and lower platelets adhesion, monomer vinyl pyrrolidone (NVP) is grafted onto the hydrophobic polyacrylate intraocular lens surface in a certain reaction conditions. Specific changes in intraocular lens are detected by static contact angle (CA), scanning electron microscope (SEM) and light transmittance. The results show that this surface modification can greatly improve its hydrophilic character and surface formation. 展开更多
关键词 hydrophobic polyacrylate intraocular lens vinyl pyrrolidone argon ion irradiation graft surface modification
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Human evacuation affected by smoke movement in mine fires 被引量:1
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作者 Peng Chen ShUong Guo Yong Wang 《International Journal of Coal Science & Technology》 EI 2016年第1期28-34,共7页
The objective of this work is to investigate the influence of smoke movement during mine fires on miner evacuation behaviors. A three-dimensional computational fluid dynamics method was conducted to reconstruct the la... The objective of this work is to investigate the influence of smoke movement during mine fires on miner evacuation behaviors. A three-dimensional computational fluid dynamics method was conducted to reconstruct the lane- way conveyor belt fire scenes under two ventilating conditions. The parameters, including temperature-time histories, soot density, carbon monoxide and heat release rate, were simulated to characterize the mine fires at various ventilating speeds. A miner evacuation model affected by fire smoke movement was advanced to describe the miner evacuation behaviors, which can be divided into three stages. Based on the evacuation model coupled with the mine fire smoke movement, the available safety evacuation time for miners involved in coal mine fire located in different sites was estimated. Two evacuation patterns were advanced according to the ventilating speeds combined with the model of miner evacuation behaviors. The results show that the miners located between the inlet-air end and the air door in lane 1 should be evacuated to the inlet-air end and other miners involved in coal mine fire could choose the air door as the escaping destination, when the ventilation speed is greater than 3 m/s. Accordingly, the research can be used as references for the mine safety administration authorities to design the safety evacuation. 展开更多
关键词 Mine fires Smoke movement Evacuation behaviors Evacuation patterns
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A novel colloid probe preparation method based on chemical etching technique
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作者 XU Hui XU Guo-hua AN Yue 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第4期304-309,共6页
Several fundamental problems in hydrophobic force measurements using atomic force microscope (AFM) are dis-cussed in this paper. A novel method for colloid probe preparation based on chemical etching technology is pro... Several fundamental problems in hydrophobic force measurements using atomic force microscope (AFM) are dis-cussed in this paper. A novel method for colloid probe preparation based on chemical etching technology is proposed, which is specially fit for the unique demands of hydrophobic force measurements by AFM. The features of three different approaches for determining spring constants of rectangular cantilevers, including geometric dimension, Cleveland and Sader methods are com-pared. The influences of the sizes of the colloids on the measurements of the hydrophobic force curves are investigated. Our experimental results showed that by selecting colloid probe with proper spring constant and tip size, the hydrophobic force and the complete hydrophobic interaction force curve can be measured by using AFM. 展开更多
关键词 Hydrophobic force Atomic force microscope (AFM) Colloid probe Chemical etching
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VITAMIN-D RECEPTOR GENE POLYMORPHISM AND ITS RELATIONSHIP WITH BONE MINERAL DENSITY IN POSTMENOPAUSAL OSTEOPOROTIC WOMEN IN SHANGHAI
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作者 王卫庆 高国峰 +2 位作者 宁光 王曙 罗邦尧 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2002年第1期25-25,共1页
Objective To examine the relationship between the vitamin D receptor(VDR) gene polymorphism and osteoporosis in postmenopausal women in Shanghai. Methods 102 postmenopausal women recruited from Ruijin Hospital were os... Objective To examine the relationship between the vitamin D receptor(VDR) gene polymorphism and osteoporosis in postmenopausal women in Shanghai. Methods 102 postmenopausal women recruited from Ruijin Hospital were osteoporotic. We measured the lumbar vertebrae and femur of all patients with a modal dual-energy X-ray absorptionmetry, and also the serum osteocalcin by ELISA. The VDR gene was amplified using a polymerase chain reaction (PCR). The VDR genotypes were determined by the PCR-RFLP. Results bb, aa and TT genotype were found mainly in these osteoporosis patients, only one BB and two tt were found among these patients. No significant association was observed among three subgroups of bb, Bb and BB. Conclusion The rareness of B and t alleles suggested that it is unlikely that they are important factors for the heredity of osteoporosis in Chinese women. Thus VDR gene typing may be of little value in assessing the osteoporosis risk in Chinese population. 展开更多
关键词 osteoporosis vitamin D receptor bone mineral density
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