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DECAY PROCESSES OF HIGH-FREQUENCY NONEQUILIBRIUM PHONONS IN PRASEODYMIUM-DOPED LASER CRYSTALS

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发光学报 1999年第2期 40-48页

作者： wang Xiaojun a) Dennis w M b) Yen w M b) a) (Department of Physics & Astronomy, Georgia Southern University, Statesboro, GA 30460, USA) b) (Department of Physics and Astronomy, The University of Georgia, Athens, GA 3

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１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃｈｒｏｍａｔｉｃｎｏｎｅｑｕｉｌｉ...

关键词： nonequilibrium phonons high frequency phonons lattice dynamics YAG YLF

On the Mechanism of CDOs behind the Current Financial Crisis and Mathematical Modeling with Levy Distributions

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Intelligent Information Management 2010年第2期2卷 149-158页

作者： H.w. Du J.L. wu w. Yang 不详

This paper aims to reveal the mechanism of Collateralized Debt Obligations (CDOs) and how CDOs extend the current global financial crisis. we first introduce the concept of CDOs and give a brief account of the de-velopment of CDOs. we then explicate the mechanism of CDOs within a concrete example with mortgage deals and we outline the evolution of the current financial crisis. Based on our overview of pricing CDOs in various existing random models, we propose an idea of modeling the random phenomenon with the feature of heavy tail dependence for possible implements towards a new random modeling for CDOs.

关键词： Collateralized Debt Obligations (CDOs) Cashflow CDO Synthetic CDO Mechanism Financial Crisis Pricing Models Levy Stable Distributions

Identification of Conserved Regulatory Elements in Mammalian Promoter Regions:A Case Study Using the PCK1 Promoter

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Genomics, Proteomics & Bioinformatics 2008年第3期6卷 129-143页

作者： George E. Liui Matthew T. weirauch Curtis P. Van Tassell Robert w. Li Tad S. Sonstegard LakshmiK. Matukumal Erin E. Connor Richard w. Hanson Jianqi Yang Bovine Functional Genomics Laboratory Beltsville Agricultural Research Center Beltsville MD 20705 USA Department of Biomolecular Engineering University of California Santa Cruz Santa Cruz CA 95064 USA Department of Bioinformatics and Computational Biology George Mason University Manassas VA 20110 USA Department of Biochemistry Case Western Reserve University School of Medicine Cleveland OH 44106 USA.

A systematic phylogenetic footprinting approach was performed to identify conserved transcription factor binding sites （TFBSs） in mammalian promoter regions using human, mouse and rat sequence alignments. we found that the score distributions of most binding site models did not follow the Gaussian distribution required by many statistical methods. Therefore, we performed an empirical test to establish the optimal threshold for each model. we gauged our computational predictions by comparing with previously known TFBSs in the PCK1 gene promoter of the cytosolic isoform of phosphoenolpyruvate carboxykinase, and achieved a sensitivity of 75% and a specificity of approximately 32% Almost all known sites overlapped with predicted sites, and several new putative TFBSs were also identified. we validated a predicted SP1 binding site in the control of PCK1 transcription using gel shift and reporter assays. Finally, we applied our computational approach to the prediction of putative TFBSs within the promoter regions of all available RefSeq genes. Our full set of TFBS predictions is freely available at http：//***/tfbsConsSites.

关键词： phylogenetic footprinting phosphoenolpyruvate carboxykinase transcription factor binding sites mammalian gene promoters

Gene therapy for Parkinson’s Disease and Ethical Challenges: A Systematic Review

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Advances in Parkinson's Disease 2023年第2期12卷 9-28页

作者： Théodora M. Zohoncon Joseph Sawadogo Abdou Azaque Zoure Abdoul Karim Ouattara Marie N. L. Ouedraogo Luc Zongo Paul Ouedraogo Florencia w. Djigma Christelle w. M. Nadembèga Raphael Kabore Djénéba Ouermi Dorcas Obiri-Yeboah Jacques Simpore Pietro Annigoni Biomolecular Research Centre (CERBA) Ouagadougou Burkina Faso Faculty of Medicine University Saint Thomas d’Aquin (USTA) Ouagadougou Burkina Faso Saint Camille Hospital Ouagadougou (HOSCO) Ouagadougou Burkina Faso Molecular Biology and Genetics Laboratory (LABIOGENE) Joseph KI-ZERBO University Ouagadougou Burkina Faso National Center for Scientific and Technological Research (CNRST/IRSS) Ouagadougou Burkina Faso Norbert Zongo University/Manga University Centre Koudougou Burkina Faso Department of Microbiology and Immunology School of Medical Sciences University of Cape Coast Cape Coast Ghana

Background: Parkinson’s disease (PD) is a complex, multifactorial neurodegenerative disorder with a pathophysiology deriving from the synergy of abnormal aggregation of neuroinflammation, synuclein and dysfunction of lysosomes, mitochondria and synaptic transport difficulties influenced by genetic and idiopathic factors. worldwide, PD has a prevalence of 2-3% in people over the age of 65. To date, there is no certified, effective treatment for PD. Aim: The aims of this research were: (i) to present, on the basis of recent advances in molecular genetics and epigenetics, the genomic aspects and challenges of gene therapy trials for PD;(ii) to outline the ethical principles applicable to therapeutic trials for PD. Method: A systematic literature review was carried out to identify relevant articles reporting on genomic aspects and gene therapy in PD from 2001 to October 2023. The search was conducted in French and/or English in three databases: PubMed, Google Scholar and Science Direct. PRISMA guidelines were used in this systematic review. Results: A total of thirty-three publications were selected. An inductive thematic analysis revealed that numerous genetic mutations (SNCA, Parkin, PINK1, DJ-1, LRRK2, ATP13A2, VPS35, Parkin/PRKN, PINK1, DJ1/PARK7) and epigenetic events such as the action of certain miRNAs (miR-7, miR-153, miR-133b, miR-124, miR-137) are responsible for the onset of PD, and that genetic therapy for this pathology raises ethical questions that need to be elucidated in the light of the bioethical principles of autonomy, beneficence, non-maleficence and justice. Conclusion: There is no zero risk in biotechnology. Then, it will be necessary to assess all the potential risks of Parkinson disease’s gene therapy to make the right decision. It is therefore essential to pursue research and, with the guidance of ethics, to advance treatment options and meet the challenges of brain manipulation and its impact on human identity. The golden rule of medicine remai

关键词： Neurodegenerative Diseases Parkinson Disease Molecular Mechanism Gene Therapy Gene Therapy Ethics

CONTROL OF STRONG SHOCK—TURBULENT BOUNDARY LAYER INTERACTION IN RECTANGULAR CHANNELS

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Chinese Journal of Aeronautics 1992年第1期 5-11页

作者： He Z w, Li F B (Nanjing Aeronautical Institute, Nanjing, 210016)

Under initial conditions of Ma= 1.63 and δ= 5.65mm, the controlling techniquesof strong shock-turbulent boundary layer interactions in rectangular channels are investigatedsystematically in this paper. It is found that for an effective improvement on boundarylayer parameters and reducing the turbulence level of flow downstream ofshock-boundary layer interaction, the bleed mass flow G = 2～2.5%, and the width of suctionslot w/δ= 0.88 and its position of L / δ= 1.77 are the most suitable values amongthe G, w /δ, L/ δand B studied. Experiments reveal that for improving the steadyand dynamic characteristics of flow in the channels it is necessary for channels with highvalue of Bto control effectively the strong shock-boundary layer interaction.

关键词： CONTROL OF STRONG SHOCK TURBULENT BOUNDARY LAYER INTERACTION IN RECTANGULAR CHANNELS

模拟定向凝固生长速率对杆形Mn-Bi合金共晶间距的影响

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铸造 2003年第6期52卷 395-399页

作者：王君卿 Mustafa Kaya Reginald w.Smith 沈阳铸造研究所辽宁沈阳110022 皇后大学

为了深入了解定向凝固过程生长速率对杆形Mn Bi合金共晶间距的影响,开展了试验和数值模拟研究工作,以期初步明确在地球上试验得到的杆形共晶间距和在外层空间(航天飞机上)同样试验条件下得到的杆形共晶间距发生变化这样一个事实的机理... 详细信息

为了深入了解定向凝固过程生长速率对杆形Mn Bi合金共晶间距的影响,开展了试验和数值模拟研究工作,以期初步明确在地球上试验得到的杆形共晶间距和在外层空间(航天飞机上)同样试验条件下得到的杆形共晶间距发生变化这样一个事实的机理。在杆形MnBi共晶相和Bi基体生长前沿,用传质方程计算了Mn在合金液中的浓度场,得到了液、固两相间台式界面前沿Mn的等浓度曲线,进而依据Jackson Hunt研究的理论模型计算出杆形共晶间距。试验和数值模拟的结果显示,规则生长时,随着Peclet数Λ的不断增加,杆形共晶间距逐渐减少,试验与模拟的结果吻合良好。Λ数还可在将来被用来模拟计算该合金凝固时非规则生长时的情况。

关键词： Mn—Bi合金杆形共晶间距定向凝固数值模拟磁性材料生长速率

Engineering microparticles based on solidified stem cell secretome with an augmented pro-angiogenic factor portfolio for therapeutic angiogenesis

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Bioactive Materials 2022年第11期7卷 526-541页

作者： Thomas Spater Marisa Assunçao Kwok Keung Lit Guidong Gong Xiaoling wang Yi-Yun Chen Ying Rao Yucong Li Chi Him Kendrick Yiu Matthias w.Laschke Michael D.Menger Dan wang Rocky S.Tuan Kay-Hooi Khoo Michael Raghunath Junling Guo Anna Blocki Institute for Clinical&Experimental Surgery Saarland UniversityHomburgSaarGermany School of Biomedical Sciences Faculty of MedicineThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Institute for Tissue Engineering and Regenerative Medicine The Chinese University of Hong KongShatinNew TerritoriesHong KongChina BMI Center for Biomass Materials and Nanointerfaces College of Biomass Science and EngineeringSichuan UniversityChengduSichuan610065China Bioproducts Institute Departments of Chemical and Biological EngineeringThe University of British ColumbiaVancouverBCCanada Academia Sinica Common Mass Spectrometry Facilities for Proteomics and Protein Modification Analysis and Institute of Biological ChemistryAcademia SinicaNankangTaipeiChina Shun Hing Institute of Advanced Engineering(SHIAE) Faculty of EngineeringThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Ministry of Education Key Laboratory for Regenerative Medicine School of Biomedical SciencesThe Chinese University of Hong KongShatinNew TerritoriesHong KongChina Department of Orthopaedics&Traumatology The Chinese University of Hong KongShatinNew TerritoriesHong KongHong Kong Special Administrative Region of China Institute for Chemistry and Biotechnology Zurich University of Applied SciencesWadenswilSwitzerland State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengduSichuan610065China

Tissue (re)vascularization strategies face various challenges, as therapeutic cells do not survive long enough in situ, while the administration of pro-angiogenic factors is hampered by fast clearance and insufficient ability to emulate complex spatiotemporal signaling. Here, we propose to address these limitations by engineering a functional biomaterial capable of capturing and concentrating the pro-angiogenic activities of mesenchymal stem cells (MSCs). In particular, dextran sulfate, a high molecular weight sulfated glucose polymer, supplemented to MSC cul-tures, interacts with MSC-derived extracellular matrix (ECM) components and facilitates their co-assembly and accumulation in the pericellular space. Upon decellularization, the resulting dextran sulfate-ECM hybrid material can be processed into MIcroparticles of SOlidified Secretome (MIPSOS). The insoluble format of MIPSOS protects protein components from degradation, while facilitating their sustained release. Proteomic analysis demonstrates that MIPSOS are highly enriched in pro-angiogenic factors, resulting in an enhanced pro-angiogenic bioactivity when compared to naïve MSC-derived ECM (cECM). Consequently, intravital microscopy of full-thickness skin wounds treated with MIPSOS demonstrates accelerated revascularization and healing, far superior to the ther-apeutic potential of cECM. Hence, the microparticle-based solidified stem cell secretome provides a promising platform to address major limitations of current therapeutic angiogenesis approaches.

关键词： Dextran sulfate Extracellular matrix Mesenchymal stem cells Therapeutic angiogenesis wound healing Poly-electrolyte-driven co-assembly

Superplasticity of Ti2448 Alloy with Nanostructured Grains

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Journal of Materials Science & Technology 2011年第12期27卷 1099-1104页

作者： M.J. Xiao Y.X. Tian G. w. Mao S.J. Li Y.L. Hao R. Yang School of Astronautics Northwestern Polytecllnic University Xi＇an 710072 China - Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Ti-24Nb-4Zr-8Sn, abbreviated as Ti2448 from its chemical composition in weight percent, is a multifunctional /3 type titanium alloy with body centered cubic （bcc） crystal structure, and its highly localized plastic deformation behavior contributes significantly to grain refinement during conventional cold processing. In the paper, the nanostructured （NS） alloy with grain size less than 50 nm produced by cold rolling has been used to investigate its superplastic deformation behavior by uniaxial tensile tests at initial strain rates of 1.5 ×10-2, 1.5×10^-3 and 1.6×10-4 s-1 and temperatures of 600,650 and 700℃. The results show that, in comparison with the coarse-grained alloy with size of 50 μm, the NS alloy has better superplasticity with elongation up to ～275% and ultimate strength of 50-100 MPa. Strain rate sensitivity （m） of the NS alloy is 0.21, 0.30 and 0.29 for 600,650 and 700℃, respectively. These results demonstrate that grain refinement is a valid way to enhance the superplasticity of Ti2448 alloy.

关键词： Titanium alloy bcc crystal Superplasticity Nanostructured grain

基于散射参数的船用电力电缆模型验证(英文)

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高电压技术 2011年第11期37卷 2836-2842页

作者： Lukas Graber Diomar Infante Michael Steurer william w.Brey Center for Advanced Power Systems.Florida State University Tallahassee.FL32310 USA National High Magnetic Field Laboratory Florida State UniversityTallahasseeFL32310 USA

Careful analysis of transients in shipboard power systems is important to achieve long life times of the components in future all-electric *** order to accomplish results with high accuracy,it is recommended to validate cable models as they have significant influence on the amplitude and frequency spectrum of voltage *** authors propose comparison of model and measurement using scattering *** can be easily obtained from measurement and simulation and deliver broadband information about the accuracy of the *** measurement can be performed using a vector network *** process to extract scattering parameters from simulation models is explained in *** different simulation models of a 5 kV XLPE power cable have been *** chosen approach delivers an efficient tool to quickly estimate the quality of a model.

关键词： transients cable power system scattering parameters modeling simulation