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Cellular and molecular overview of gestational diabetes mellitus:Is it predictable and preventable?

World Journal of Diabetes 2023年第11期14卷 1693-1709页

作者： pei-qi lim Yen-Ju Lai pei-Ying Ling Kuo-Hu Chen Department of Obstetrics and Gynecology Taiwan Adventist HospitalTaipei 105TaiwanChina School of Medicine George Washington UniversityWashingtonDC 20052United States Department of Obstetrics and Gynecology Taipei Tzu-Chi General HospitalTaipei 231TaiwanChina

BACKGROUND In contrast to overt diabetes mellitus(DM),gestational DM(GDM)is defined as impaired glucose tolerance induced by pregnancy,which may arise from exaggerated physiologic changes in glucose *** prevalence is reported to be as high as 20%among pregnancies depending on the screening method,gestational age,and the population *** and fetal effects of uncontrolled GDM include stillbirth,macrosomia,neonatal diabetes,birth trauma,and subsequent postpartum ***,it is essential to find the potential target population and associated predictive and preventive measures for future intensive peripartum *** To review studies that explored the cellular and molecular mechanisms of GDM as well as predictive measures and prevention *** The search was performed in the Medline and PubMed databases using the terms“gestational diabetes mellitus,”“overt diabetes mellitus,”and“insulin resistance.”In the literature,only full-text articles were considered for inclusion(237 articles).Furthermore,articles published before 1997 and duplicate articles were *** a final review by two experts,all studies(1997-2023)included in the review met the search terms and search strategy(identification from the database,screening of the studies,selection of potential articles,and final inclusion).RESULTS Finally,a total of 79 articles were collected for *** risk factors for GDM included maternal obesity or overweight,pre-existing DM,and polycystic ovary *** pathophysiology of GDM involves genetic variants responsible for insulin secretion and glycemic control,pancreaticβcell depletion or dysfunction,aggravated insulin resistance due to failure in the plasma membrane translocation of glucose transporter 4,and the effects of chronic,low-grade ***,many antepartum measurements including adipokines(leptin),body mass ratio(waist circumference and waist-to-hip ratio),and biomarkers(microRNA in extra

关键词： Gestational diabetes mellitus Overt diabetes mellitus Insulin resistance Diabetes mellitus

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Applying sub-band energy extraction to noise cancellation of ultrasonic NDT signal

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1134-1140页

作者： qi ZHANG pei-wen QUE Wei LIANG Institute of Automation Detection Shanghai Jiao Tong University Shanghai 200240 China

In ultrasonic non-destructive tests, the echo signal at the flaw is highly complex due to the interference of multiple echoes with random amplitudes and phases, and is disturbed by all kinds of noises, such as thermal noise, digitalization noise, and structure noise. In this paper, the ultrasonic signal was decomposed by empirical mode decomposition (EMD) to obtain the in-trinsic mode function (IMF) components according to ultrasonic defect echo signals occuring at the corresponding time, and the energy of the ultrasonic signal was concentrated. The IMF component selection criterion based on sub-band energy extraction was proposed to extract the ultrasonic signal component accurately and automatically from IMF components. When the selected IMF components were filtered by a band pass filter, the signal-to-noise ratio (SNR) was enhanced greatly.

关键词： Empirical mode decomposition (EMD) Signal-to-noise ratio (SNR) De-noising Non-destructive testing (NDT) Intrinsic mode function (IMF)

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Intrusion Simulation of a C60 Ball into Sliding Contact Space with Graphene Layered Surfaces

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稀有金属材料与工程 2012年第S1期41卷 132-135页

作者： qi, Zhang Diao Dongfeng pei, Li Xi An Jiao Tong Univ Sch Mech Engn Key Lab Educ Minist Modern Design & Rotor Bearing Xian 710049 Peoples R China

The intrusion process of a C60 molecular ball into a sliding contact space with garaphene layered surfaces was simulated using the Molecular Dynamic *** contact space was made up by two silicon substrates with graphene layered on the surface of the upper substrate forming an included angle which was defined as initial entry angle changing from 20°to 90°.Then a linear velocity of 30/ps was applied to the lower substrate along horizontal *** simulation was carried out using Tesoff potential of C and Si atoms at room temperature *** simulation results showed that when the intrusion angle exceeded a critical angle of 80°,the C60 ball could not intrude the contact space,and the number of the sticking atoms sharply ***,the dependence of maximum pull-off force acting on the upper substrate on the initial entry angle during the C60 intrusion process was calculated in which the critical force for C60 intrusion is *** the results showed that the upper silicon substrate was well protected by the mono graphene layer.

关键词： molecular dynamic simulation sliding contact space C60 graphene layer critical angle critical force

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FAULT CAUSED BY WATER PRESSURE IN THE HEAD-COVER CHAMBER

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Journal of Hydrodynamics 2006年第3期18卷 280-286页

作者： pei Hai-lin qi Xue-yi LI Hui LI Jian-hui pei Ze-yu College of Fluid Power and Control Lanzhou University of Technology Lanzhou 730050 China Gansu Electrical and scientifical Institute Lanzhou 730050 China Vernon Barford School Edmonton Alberta T6J2X6 Canada

Owing to the high temperature of the thrust beating pads, the No.l unit wasn＇t performed in the upgrading test at Liujiaxia Hydropower Plant. Through the experimental and theoretical analysis, it has been confirmed that the fault unit was caused by the high water pressure in the head-cover chamber. This type of the fault is out-of-the-way. After the suitable measure wags against the fault were taken, the No. 1 unit can stably operate. The conclusions and the methodology are of the certain reference value to the fault-diagnosis of the hydroelectric unit.

关键词： hydroelectric unit perturbation vibration,fault diagnosis

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Tf_2O-TMDS combination for the direct reductive transformation of secondary amides to aldimines,aldehydes, and/or amines

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Science China Chemistry 2016年第12期59卷 1638-1644页

作者： qi-Wei Lang Xiu-Ning Hu pei-qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University

The direct partial reduction of highly stable secondary amides to more reactive aldimines and aldehydes is a challenging yet highly demanding transformation. In this context, only three methods have been reported. We report herein an improved version of the Charette's method. Our protocol consists of activation of secondary amides with triflic anhydride/2-fluoropyridine,and partial reduction of the resulting intermediates with 1,1,3,3-tetramethyldisiloxane(TMDS), which delivered aldimines or aldehydes upon acidic hydrolysis. Aromatic amides were reduced to the corresponding aldimines in 85%–100% NMR yields,and yields(NMR) from aliphatic amides were 72%–86%. Acidic hydrolysis of the aldimine intermediates afforded, in one-pot,the corresponding aldehydes in 80%–96% yields. A simple protocol was established to isolate labile aldimines in pure form in92%–96% yields. The improved method gave generally higher yields as compared to the known ones, and features the use of cheaper and more atom-economical TMDS as a chemoselective reducing agent. In addition, a convenient extraction protocol has been established to allow the isolation of amines, which constitutes a mild method for the N-deacylation of amides, another highly desirable transformation. The extended method retains the advantages of the original method of Charette in terms of mild conditions, good functional group tolerance, and excellent chemoselectivity.

关键词： secondary amides amide activation partial reduction aldimines N-deacylation

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Velocity forecasts using a combined deep learning model in hybrid electric vehicles with V2V and V2I communication

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Science China(Technological Sciences) 2020年第1期63卷 55-64页

作者： pei JiaZheng SU YiXin ZHANG DanHong qi Yue LENG ZhiWen School of Automation Wuhan University of TechnologyWuhan 430070China China Ship Development and Design Center Wuhan 430064China

Vehicle velocity forecast is an important clue in improving the performance of energy management in hybrid electric vehicles(HEV). This paper presents a new combined model for predicting vehicle’s velocity time series. The main features of the model are to combine the feature extraction capability of deep restricted Boltzmann machines(DBM) and sequence pattern predicting capability of bidirectional long short-term memory(BLSTM). Hence, the model is named as DBMBLSTM. In addition, the DRMBLSTM model utilizes the vehicle driving information and roadside infrastructure information provided respectively through vehicle-to-vehicle(V2V) and vehicle-to-infrastructure(V2I) communication channels to predict vehicle velocity at various length of prediction horizon. Furthermore, the predictions results of this study are compared with the state of the art of vehicle velocity forecasts. The root mean square error(RMSE) is used as an evaluation criteria of predictions accuracy. Finally,these compared prediction model are applied in model predictive control(MPC) energy management strategy for the verifications of fuel economy improvement of a HEV. Simulation results confirm that the proposed combined deep learning model performs better than other five prediction methods. Therefore, it is a means of arriving at a reliable forecast model for HEV.

关键词： vehicle velocity prediction restricted Boltzmann machines deep belief network long short-term memory,model predictive control

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Preparation and characterization of γ-La_2S_3 nanoparticles from thermal decomposition

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 748-752页

作者： pei-sen Li Huan-yong Li Wan-qi Jie School of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

To synthesize pure γ-La2S3 at lower temperature,lanthanide complex La（Et2S2CN）3·phen,containing La？S bond,was chosen as the precursors to *** obtained samples were characterized by X-ray power diffraction （XRD）,field-emission scanning electron microscopy （FE-SEM） with an energy dispersive spectrometer and UV-Vis diffuse reflectance *** decomposition mechanism of the lanthanide complex was studied by thermogravimetric analyses （TGA）.The results show that the obtained samples are cubic phase particles with sizes among 20-50 nm and the band gap is 2.97 eV,which is bigger than that of its bulk ***/DTG results indicate that La（Et2S2CN）3·phen decomposed to γ-La2S3 via La4（Et2S2CN）3 as an intermediate product.

关键词： chalcogenides nanoparticles thermogravimetric analysis decomposition optical properties

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Probabilistic prediction on three-dimensional roughness of discontinuity based on two-dimensional traces under rock tunnel excavation based on Bayesian theory

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Underground Space 2024年第1期14卷 338-356页

作者： qi Zhang Yuechao pei Xiaojun Wang Xiaojun Li Yixin Shen School of Civil Engineering Southeast UniversityNanjing 211189China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

Three-dimensional(3D)roughness of discontinuity affects the quality of the rock mass,but 3D roughness is hard to be measured due to that the discontinuity is invisible in the ***-dimensional(2D)roughness can be calculated from the visible traces,but it is difficult to obtain enough quantity of the traces to directly derive 3D roughness during the tunnel *** this study,a new method using Bayesian theory is proposed to derive 3D roughness from the low quantity of 2D roughness *** more accurately calculating 3D roughness,a new regression formula of 2D roughness is established firstly based on wavelet *** new JRC3D prediction model based on Bayesian theory is then developed,and Markov chain Monte Carlo(MCMC)sampling is adopted to process JRC3D prediction *** discontinuity sample collected from the literature is used to verify the proposed *** groups with the sampling size of 2,3,4,and 5 of each group are randomly sampled from JRC2D values of 170 profiles of the discontinuity,*** research results indicate that 100%,90%,85%,and 60%predicting JRC3D of the sample groups corresponding to the sampling size of 5,4,3,and 2 fall into the tolerance interval[JRC_(true)–1,JRC_(true)+1].It is validated that the sampling size of 5 is enough for predicting *** sensitivities of sampling results are then analyzed on the influencing factors,which are the correlation function,the prior distribution,and the prior *** discontinuity across the excavation face at ZK78+67.5 of Daxiagu tunnel is taken as the tunnel engineering application,and the results further verify that the predicting JRC3D with the sampling size of 5 is generally in good agreement with JRC3D true values.

关键词： Rock discontinuity Joint roughness coefficient Tunnel excavation Bayesian theory Markov chain Monte Carlo sampling

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Noise robustness of an operational modal-based structural damage-detection scheme using impact-synchronous modal analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第9期24卷 782-800页

作者： pei Yi SIOW Zhi Chao ONG Shin Yee KHOO Kok-Sing lim Department of Mechanical Engineering Faculty of EngineeringUniversiti MalayaKuala Lumpur 50603Malaysia Photonics Research Centre Deputy Vice Chancellor(Research and Innovation)OfficeUniversiti MalayaKuala Lumpur 50603Malaysia

Data-driven damage-detection schemes are usually unsupervised machine-learning models in practice,as these do not require any ***-based features are commonly used in these schemes but often require several other parameters to accurately correlate with damage,as they may not globally represent the model,making them less sensitive to *** data,such as frequency response functions(FRFs)and principal component analysis(PCA)reduced FRFs(PCA-FRFs),inherits the dynamic characteristics of the structure,and it changes when damage occurs,thus showing sensitivity to ***,noise from the environment or external sources such as wind,operating machines,or the in-service system itself,can reduce the modal data's sensitivity to damage if not handled properly,which affects damage-detection *** study proposes a noise-robust operational modal-based structural damage-detection scheme that uses impact-synchronous modal analysis(ISMA)to generate clean,static-like FRFs for damage *** allows modal data collection without requiring shutdown conditions,and its denoising feature aids in generating clean,static-like FRFs for damage *** results showed that the FRFs obtained through ISMA under noise conditions have frequency response assurance criterion(FRAC)and cross signature assurance criterion(CSAC)scores greater than 0.9 when compared with FRFs obtained through experimental modal analysis(EMA)under static conditions;this validates the denoising feature of *** the denoised FRFs are reduced to PCA-FRFs and used in an unsupervised learning-based damage-detection scheme,zero false alarms occur.

关键词： Impact-synchronous modal analysis(ISMA) Frequency response function(FRF) Principal component analysis(PCA) Unsupervised learning Damage detection

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Multiple biomarkers response in maize (Zea mays L.)during exposure to copper

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Journal of Environmental Sciences 2006年第6期18卷 1182-1188页

作者： qi Xue-mei LI pei-jun LIU Wan XIE Li-jing Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China College of Energy and Environmental Engineering Shanghai University of Electric Power Shanghai 200090 China College of Resource and Environment North East Agriculture University Harbin 150030 China

Biomarkers in higher plants played an important role to estimate exposure effects of pollutants in soil ecosystem and have received increasing attention in recent years. The qualitative and quantitative modifications arising in amplified fragment length polymorphism （AFLP） profiles as a measure of DNA effects were compared with a number of parameters, namely, the root length, total soluble protein content in root tips, chlorophylls content and shoot size to select the most sensitive biomarker responding to copper stress in the range of 0--600 mg/kg. The changes occurring in AFLP profiles of root tips following Cu treatment included loss of normal bands and appearance of new bands and variation in band intensity in comparison to that of the normal seedlings, A reduction in root length was observed at the 200 mg/kg of copper, which was accompanied with a decrease in total soluble protein content. According to their sensitivity to the copper toxicity, the above indicator rank in the following order： AFLP profiles 〉 total soluble protein content 〉 root length 〉 chlorophylls content 〉 shoot. We concluded that the AFLP offered a useful alternative hiomarker assay for the detection of genotoxic effects of environmental pollutants.

关键词： copper biomarker genotoxicity DNA damage

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