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Cumulus-specific genes are transcriptionally silent following somatic cell nuclear transfer in a mouse model

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 533-539页

作者： TONG Guo-qing heng boon-chin NG Soon-chye Nuclear Reprogramming and Stem Cell Laboratory Department of Obstetrics and Gynecology Yong Loo Lin School of Medicine National University of Singapore 119074 Singapore Stem Cell and Developmental Biology Group Genome Institute of Singapore 138672 Singapore Stem Cell Laboratory Faculty of Dentistry National University of Singapore 119074 Singapore Embryonics International Pte Ltd. Gleneagles Hospital 258500 Singapore

This study investigated whether four cumulus-specific genes: follicular stimulating hormone receptor (FSHr), hyaluronan synthase 2 (Has2), prostaglandin synthase 2 (Ptgs2) and steroidogenic acute regulator protein (Star), were correctly reprogrammed to be transcriptionally silent following somatic cell nuclear transfer (SCNT) in a murine model. Cumulus cells of C57×CBA F1 female mouse were injected into enucleated oocytes, followed by activation in 10 μmol/L strontium chloride for 5 h and subsequent in vitro culture up to the blastocyst stage. Expression of cumulus-specific genes in SCNT-derived embryos at 2-cell, 4-cell and day 4.5 blastocyst stages was compared with corresponding in vivo fertilized embryos by real-time PCR. It was demonstrated that immediately after the first cell cycle, SCNT-derived 2-cell stage embryos did not express all four cumulus-specific genes, which continually remained silent at the 4-cell and blastocyst stages. It is therefore concluded that all four cumulus-specific genes were correctly reprogrammed to be silent following nuclear transfer with cumulus donor cells in the mouse model. This would imply that the poor preimplantation developmental competence of SCNT embryos derived from cumulus cells is due to incomplete reprogramming of other embryonic genes, rather than cumulus-specific genes.

关键词： Somatic cell nuclear transfer (SCNT) Nuclear reprogramming Embryo Development

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The circadian clock in enamel development

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International Journal of Oral Science 2024年第3期16卷 371-380页

作者： Ke Wu Xiaochan Li Yunyang Bai boon chin heng Xuehui Zhang Xuliang Deng Department of Geriatric Dentistry Peking University School and Hospital of StomatologyBeijingChina th Division Peking University School and Hospital of StomatologyBeijingChina Department of Dental Materials&Dental Medical Devices Testing Center Peking University School and Hospital of StomatologyBeijingChina National Engineering Research Center of Oral Biomaterials and Digital Medical Devices NMPA Key Laboratory for Dental MaterialsBeijing Laboratory of Biomedical Materials&Beijing Key Laboratory of Digital StomatologyPeking University School and Hospital of StomatologyBeijingChina Oral Translational Medicine Research Center Joint Training base for Shanxi Provincial Key Laboratory in Oral and Maxillofacial Repair Reconstruction and Regeneration The First People’s Hospital of Jinzhong JinzhongChina

Circadian rhythms are self-sustaining oscillations within biological systems that play key roles in a diverse multitude of physiological *** circadian clock mechanisms in brain and peripheral tissues can oscillate independently or be synchronized/disrupted by external *** enamel is a type of mineralized tissue that forms the exterior surface of the tooth *** Retzius lines are readily observable microstructures of mature tooth enamel that indicate the regulation of amelogenesis by circadian *** enamel is formed by enamel-forming cells known as ameloblasts,which are regulated and orchestrated by the circadian clock during *** review will first examine the key roles of the circadian clock in regulating ameloblasts and *** physiological processes are involved,including gene expression,cell morphology,metabolic changes,matrix deposition,ion transportation,and ***,the potential detrimental effects of circadian rhythm disruption on enamel formation are *** rhythm disruption can directly lead to Enamel Hypoplasia,which might also be a potential causative mechanism of amelogenesis ***,future research trajectory in this field is *** is hoped that this review will inspire more intensive research efforts and provide relevant cues in formulating novel therapeutic strategies for preventing tooth enamel developmental abnormalities.

关键词： enamel crown exterior

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Cell membrane vesicles derived from hBMSCs and hUVECs enhance bone regeneration

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Bone Research 2024年第2期12卷 361-371页

作者： Dandan Wang Yaru Guo boon chin heng Xuehui Zhang Yan Wei Ying He Mingming Xu Bin Xia Xuliang Deng Department of Pediatric Dentistry Peking University School and Hospital of StomatologyBeijing 100081P.R.China Department of Geriatric Dentistry Peking University School and Hospital of StomatologyNational Center for StomatologyNational Clinical Research Center for Oral DiseasesNational Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijing 100081P.R.China Department of Dental Materials&Dental Medical Devices Testing Center Peking University School and Hospital of StomatologyNational Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijing 100081P.R.China

Bone tissue renewal can be enhanced through co-transplantation of bone mesenchymal stem cells(BMSCs)and vascular endothelial cells(ECs).However,there are apparent limitations in stem cell-based therapy which hinder its clinic ***,we investigated the potential of alternative stem cell substitutes for facilitating bone *** this study,we successfully prepared cell membrane vesicles(CMVs)from BMSCs and *** results showed that BMSC-derived cell membrane vesicles(BMSC-CMVs)possessed membrane receptors involved in juxtacrine signaling and growth factors derived from their parental ***-derived cell membrane vesicles(EC-CMVs)also contained BMP2 and VEGF derived from their parental ***-CMVs enhanced tube formation and migration ability of hUVECs,while EC-CMVs promoted the osteogenic differentiation of hBMSCs in *** a rat skull defect model,we found that co-transplantation of BMSC-CMVs and EC-CMVs could stimulate angiogenesis and bone formation in ***,our research might provide an innovative and feasible approach for cell-free therapy in bone tissue regeneration.

关键词： hinder apparent vesicles

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Value iteration algorithm for continuous-time linear quadratic stochastic optimal control problems

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Science china(Information Sciences) 2024年第2期67卷 170-180页

作者： Guangchen WANG heng ZHANG School of Control Science and Engineering Shandong University

In this study, we investigate a continuous-time infinite-horizon linear quadratic stochastic optimal control problem with multiplicative noise in control and state variables. Using the techniques of stochastic stability, exact observability, and stochastic approximation, a value iteration algorithm is developed to solve the corresponding generalized algebraic Riccati equation. Unlike the existing policy iteration algorithm, this algorithm does not rely on an initial stabilizing control. Further, this algorithm can also be used to compute policy evaluation steps that arise in the policy iteration algorithm. Herein, a simulation example is provided to validate the obtained results.

关键词： stochastic systems optimal control linear quadratic stochastic problem generalized algebraic Riccati equation value iteration algorithm

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Genetic diversity of the S-type small subunit ribosomal RNA gene of Plasmodium knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia

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Asian Pacific Journal of Tropical Medicine 2024年第2期17卷 84-90页

作者： Eric Tzyy Jiann Chong Joveen Wan Fen Neoh Tiek Ying Lau Kek heng Chua Yvonne Ai-Lian Lim Ping-chin Lee Biotechnology Research Institute Universiti Malaysia SabahJalan UMS88400 Kota KinabaluSabahMalaysia Department of Biomedical Science Faculty of Medicine BuildingUniversity of Malaya50603 Kuala LumpurMalaysia Centre of Excellence for Research in AIDS(CERiA) University of Malaya50603 Kuala LumpurMalaysia Faculty of Science and Natural Resources Universiti Malaysia SabahJalan UMS88400 Kota KinabaluSabahMalaysia

Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and ***:Thirty-nine blood samples infected with *** were collected in Sabah,Malaysian Borneo and Peninsular *** S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and *** natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK *** study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA ***:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of *** isolates from different areas in Malaysia based on the S-type SSU rRNA gene *** S-type SSU rRNA gene sequences were relatively conserved and with a purifying *** sharing of the S-type SSU rRNA gene was observed between the *** isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular ***:This study suggests that the S-type SSU rRNA gene of *** isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the *** features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among *** species.

关键词： Plasmodium knowlesi S-type small subunit ribosomal RNA Genetic diversity Natural selection Haplotype

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Effect of nocturia in patients with different severity of obstructive sleep apnea on polysomnography: A retrospective observational study

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Asian Journal of Urology 2024年第3期11卷 486-496页

作者： chin-heng Lu Hung-Min Chang Kuang-Hsi Chang Yen-Chuan Ou Chao-Yu Hsu Min-Che Tung Frank Cheau-Feng Lin Stella chin-Shaw Tsai Division of Urology Department of SurgeryTungs’Taichung Metroharbor HospitalTaichungTaiwanChina Rong Hsing Research Center for Translational Medicine Chung Hsing UniversityTaichungTaiwanChina College of Life Sciences Chung Hsing UniversityTaichungTaiwanChina Department of Otolaryngology Tungs’Taichung Metroharbor HospitalTaichungTaiwanChina Department of Medical Research Tungs’Taichung Metroharbor HospitalTaichungTaiwanChina General Education Center Jen-Teh Junior College of MedicineNursing and ManagementMiaoliTaiwanChina Graduate Institute of Biomedical Sciences China Medical UniversityTaichungTaiwanChina Department of Post-Baccalaureate Medicine College of MedicineChung Hsing UniversityTaichungTaiwanChina Department of Nursing Jen-Teh Junior College of MedicineNursing and ManagementMiaoliTaiwanChina Department of Surgery Chung Shan Medical UniversityTaichungTaiwanChina College of Medicine Chung Shan Medical UniversityTaichungTaiwanChina

Patients with suspected OSA were examined using *** were divided into two groups based on the presence of *** was defined as a patient who needed to void at least *** index(AHI)was employed to classify patients according to degrees of severity:AHI<5 events/h,5 events/hAHI<15 events/h,15 events/hAHI<30 events/h,and AHI30 events/h,defined as normal,mild OSA,moderate OSA,and severe OSA,*** variables,PSG parameters,International Prostate Symptom Scores(IPSSs),and quality of life scores due to urinary symptoms were ***:In total 140 patients,114 patients had OSA(48 had mild OSA;34 had moderate OSA;and 32 had severe OSA)and 107 patients had *** total IPSS was significantly higher in nocturia patients in all groups except the group of severe OSA *** the increasing severity of OSA,more correlated factors related to nocturia were *** mild OSA patients,nocturia related to increased age(p=0.025),minimum arterial blood oxygenation saturation(p=0.046),and decreased AHI of non-rapid eye movement(p=0.047),AHI of total sleep time(p=0.010),and desaturation index(p=0.012).In moderate OSA patients,nocturia related to increased age(p<0.001),awake time(p=0.025),stage 1 sleep(p=0.033),and sleep latency(p=0.033),and decreased height(p=0.044),weight(p=0.025),and sleep efficiency(p=0.003).In severe OSA patients,nocturia related to increased weight(p=0.011),body mass index(p=0.009),awake time(p=0.008),stage 1 sleep(p=0.040),arousal number(p=0.030),arousal index(p=0.013),periodic limb movement number(p=0.013),and periodic limb movement index(p=0.004),and decreased baseline arterial blood oxygenation saturation(p=0.046).Conclusion:Our study revealed that there were more correlated factors related to nocturia with increasing severity of *** study helps in clinical education and treatment for OSA patients with different severity.

关键词： Nocturia Obstructive sleep apnea Polysomnography Apneaehypopnea index International Prostate Symptom Score

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Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective

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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-heng Du Yong-Min Shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

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An attention graph stacked autoencoder for anomaly detection of electro-mechanical actuator using spatio-temporal multivariate signals

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chinESE JOURNAL OF AERONAUTICS 2024年第9期37卷 506-520页

作者： Wang, Jianyu Zhang, heng Miao, Qiang Sichuan Univ Coll Elect Engn Chengdu 610065 Peoples R China

Health monitoring of electro-mechanical actuator (EMA) is critical to ensure the security of airplanes. It is difficult or even impossible to collect enough labeled failure or degradation data from actual EMA. The autoencoder based on reconstruction loss is a popular model that can carry out anomaly detection with only consideration of normal training data, while it fails to capture spatio-temporal information from multivariate time series signals of multiple monitoring sensors. To mine the spatio-temporal information from multivariate time series signals, this paper proposes an attention graph stacked autoencoder for EMA anomaly detection. Firstly, attention graph convolution is introduced into autoencoder to convolve temporal information from neighbor features to current features based on different weight attentions. Secondly, stacked autoencoder is applied to mine spatial information from those new aggregated temporal features. Finally, based on the benchmark reconstruction loss of normal training data, different health thresholds calculated by several statistic indicators can carry out anomaly detection for new testing data. In comparison with traditional stacked autoencoder, the proposed model could obtain higher fault detection rate and lower false alarm rate in EMA anomaly detection experiment. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of chinese Society of Aeronautics and Astronautics.

关键词： Anomaly detection Spatio-temporal informa- tion Multivariate time series sig- nals Attention graph convolu- tion Stacked autoencoder FAULT-DIAGNOSIS

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Numerical manifold method for steady-state nonlinear heat conduction using Kirchhoff transformation

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Science china(Technological Sciences) 2024年第4期67卷 992-1006页

作者： ZHANG LiMei KONG heng Zheng Hong Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Municipal Construction Co. Ltd.Beijing 100048China

The numerical manifold method(NMM)introduces the mathematical and physical cover to solve both continuum and discontinuum problems in a unified *** this study,the NMM for solving steady-state nonlinear heat conduction problems is presented,and heat conduction problems consider both convection and radiation boundary ***,the nonlinear governing equation of thermal conductivity,which is dependent on temperature,is transformed into the Laplace equation by introducing the Kirchhoff *** transformation reserves linearity of both the Dirichlet and the Neumann boundary conditions,but the Robin and radiation boundary conditions remain ***,the NMM is employed to solve the Laplace equation using a simple iteration procedure because the nonlinearity focuses on parts of the problem domain ***,the temperature field is retrieved through the inverse Kirchhoff *** examples are analyzed,demonstrating the advantages of the Kirchhoff transformation over the direct solution of nonlinear equations using the NewtonRaphson *** study provides a new method for calculating nonlinear heat conduction.

关键词： numerical manifold method nonlinear heat conduction temperature-dependent thermal conductivity Kirchhoff transformation convection and radiation boundary conditions

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Simulation of roof snow loads based on a multi-layer snowmelt model:Impact of building heat transfer

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Building Simulation 2024年第6期17卷 907-932页

作者： Xuanyi Zhou heng Chen Yue Wu Tiange Zhang State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai200092China

To investigate the impact of building heat transfer on roof snow loads,roof snow loads and snow load thermal coefficients from 61 chinese sites over a period of 50 years are simulated based on basic meteorological data such as temperature,humidity,wind speed,and precipitation,and a multi-layer snowmelt model considering the building heat ***,the accuracy of the multi-layer snowmelt model is validated using the data of observed ground snow load and roof snow melting *** relationship between meteorological conditions,snow cover characteristics,and thermal coefficients of snow loads in three representative sites is then ***,the characteristics of thermal coefficients in each zone are analyzed by combining them with the statistical results of meteorological data from 1960 to 2010,and the equations of thermal coefficients in different zones on indoor temperatures and roof heat transfer coefficients are fitted ***,the equations in this paper are compared with the thermal coefficients in the main snow load *** results indicate that the snowmelt model using basic meteorological data can effectively provide samples of roof snow *** the cold zone where the snow cover lasts for a long time and does not melt easily,the thermal coefficients of the snow loads on the heating buildings are lower than those in the warm zone due to the long-term influence of the heat from inside the *** coefficients are negatively correlated with indoor temperatures and roof heat transfer *** the indoor temperature is too low or the roof insulation is good,the roof snow load may exceed the ground snow *** thermal coefficients for heated buildings in the main snow load codes are more conservative than those calculated in this paper,and the thermal coefficients for buildings with lower indoor temperatures tend to be smaller.

关键词： snowmelt model roof snow load building heat transfer thermal coefficient load code

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