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Frontiers of Structural and Civil Engineering 2016年第3期10卷 303-311页

作者： chung-che chou Ping-Ting chung Tsung-Han WU Alexis Rafael Ovalle BEATO Department of Civil Engineering Taiwan University Taipei Taiwan China Director Center for Earthquake Engineering Research (CEER) Taiwan University Taipei Taiwan China

A steel dual-core self-centering brace （DC-SCB） is an innovative structural member that provides both energy dissipation and self-centering properties to structures, reducing maximum and residual drifts of structures in earthquakes. The axial deformation capacity of the DC-SCB is doubled by a parallel arrangement of two inner cores, one outer box and two sets of tensioning elements. This paper presents cyclic test results of a DC-SCB component and a full- scale one-story, one-bay steel frame with a DC-SCB. The DC-SCB that was near 8 m-long was tested to evaluate its cyclic behavior and durability. The DC-SCB performed well under a total of three increasing cyclic loading tests and 60 low- cycle fatigue loading tests without failure. The maximum axial load of the DC-SCB was near 1700 kN at an interstory drift of 2.5%. Moreover, a three-story dual-core self-centering braced frame （DC-SCBF） with a single-diagonal DC-SCB was designed and its first-story, one-bay DC-SCBF subassembly specimen was tested in multiple earthquake-type loadings. The one-story, one-bay subassembly frame specimen performed well up to an interstory drift of 2% with yielding at the column base and local buckling in the steel beam; no damage of the DC-SCB was found after all tests. The maximum residual drift of the DC-SCBF caused by beam local buckling was 0.5% in 2.0% drift cycles.

关键词： dual-core self-centering brace （DC-SCB） braced frame tests residual deformation

Seismic tests of post-tensioned self-centering building frames with column and slab restraints

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Frontiers of Structural and Civil Engineering 2011年第3期5卷 323-334页

作者： chung-che chou Jun-Hen cheN Department of Civil Engineering Taiwan UniversityTaipeiChina Federal Engineering Consultant Inc. TaipeiChina

Post-tensioned(PT)self-centering moment frames have been developed as an alternative to typical moment-resisting frames(MRFs)for earthquake resistance.When a PT frame deforms laterally,gaps between the beams and columns open.However,the gaps are constrained by the columns and the slab in a real PT selfcentering building frame.This paper presents a methodology for evaluating the column restraint and beam compression force based on the column deformation and gap openings at all stories.The method is verified by cyclic tests of a full-scale,two-bay by one-story PT frame.Moreover,a sliding slab is proposed to minimize restraints on the expansion of the PT frame.Shaking table tests were conducted on a reduced-scale,two-by-two bay one-story specimen,which comprises one PT frame and two gravitational frames.The PT frame and gravitational frames are self-centering throughout the tests,responding in phase with only minor differences in peak drifts caused by expansion of the PT frame.When the specimen is excited by a simulation of the 1999 Chi-Chi earthquake with a peak ground acceleration of 1.87 g,the maximum interstory drift and the residual drift are 7.2%and 0.01%,respectively.

关键词： post-tensioned frame frame expansion column restraint sliding slab frame test shake table test

Targeting NAD Metabolism for the Therapy of Age-Related Neurodegenerative Diseases

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Neuroscience Bulletin 2024年第2期40卷 218-240页

作者： Feifei Li chou Wu Gelin Wang School of Pharmaceutical Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China Tsinghua-Peking Joint Center for Life Sciences Tsinghua UniversityBeijing 100084China

As the aging population continues to grow rapidly, age-related diseases are becoming an increasing burden on the healthcare system and a major concern for the well-being of elderly individuals. While aging is an inevitable process for all humans, it can be slowed down and age-related diseases can be treated or alleviated. Nicotinamide adenine dinucleotide (NAD) is a critical coenzyme or cofactor that plays a central role in metabolism and is involved in various cellular processes including the maintenance of metabolic homeostasis, post-translational protein modifications, DNA repair, and immune responses. As individuals age, their NAD levels decline, and this decrease has been suggested to be a contributing factor to the development of numerous age-related diseases, such as cancer, diabetes, cardiovascular diseases, and neurodegenerative diseases. In pursuit of healthy aging, researchers have investigated approaches to boost or maintain NAD levels. Here, we provide an overview of NAD metabolism and the role of NAD in age-related diseases and summarize recent progress in the development of strategies that target NAD metabolism for the treatment of age-related diseases, particularly neurodegenerative diseases.

关键词： Ageing Neuroprotection NAD metabolism Therapeutic strategy Neurodegenerative diseases

Data-Driven Modeling of Partially Observed Biological Systems

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Communications on Applied Mathematics and Computation 2024年第1期6卷 739-754页

作者： Wei-Hung Su Ching-Shan chou Dongbin Xiu Department of Mathematics The Ohio State UniversityColumbusOH43221USA

We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical behavior.As an extension of the recently developed deep neural network(DNN)learning methods,our approach is particularly suitable for practical situations when(i)measurement data are available for only a subset of the state variables,and(ii)the system parameters cannot be observed or measured at all.We demonstrate that,with a properly designed DNN structure with memory terms,effective DNN models can be learned from such partially observed data containing hidden parameters.The learned DNN model serves as an accurate predictive tool for system analysis.Through a few representative biological problems,we demonstrate that such DNN models can capture qualitative dynamical behavior changes in the system,such as bifurcations,even when the parameters controlling such behavior changes are completely unknown throughout not only the model learning process but also the system prediction process.The learned DNN model effectively creates a“closed”model involving only the observables when such a closed-form model does not exist mathematically.

关键词： Deep neural network(DNN) Governing equation discovery Biological system Partial observation

Predictive factors for percutaneous nephrolithotomy bleeding risks

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Asian Journal of Urology 2024年第1期11卷 105-109页

作者： U Phun Loo Chun Hou Yong Guan chou Teh Urology Department Sarawak General HospitalKuchingMalaysia

Objective:This study aimed to identify predictive factors for percutaneous nephrolithotomy(PCNL)bleeding risks.With better risk stratification,bleeding in high-risk patient can be anticipated and facilitates early identification.Methods:A prospective observational study of PCNL performed at our institution was done.All adults with radio-opaque renal stones planned for PCNL were included except those with coagulopathy,planned for additional procedures.Factors including gender,co-morbidities,body mass index,stone burden,puncture site,tract dilatation size,operative position,surgeon's seniority,and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin(Hb)deficiency.Results:Overall,4.86%patients(n=7)received packed cells transfusion.The mean estimated Hb deficiency was 1.3(range 0-6.5)g/dL and the median was 1.0 g/dL.Stepwise multivariate regression analysis revealed that absence of hypertension(p=0.024),puncture site(p=0.027),and operative duration(p=0.023)were significantly associated with higher estimated Hb deficiency.However,the effect sizes are rather small with partial eta-squared of 0.037,0.066,and 0.038,respectively.Observed power obtained was 0.621,0.722,and 0.625,respectively.Other factors studied did not correlate with Hb difference.Conclusion:Hypertension,puncture site,and operative duration have significant impact on estimated Hb deficiency during PCNL.However,the effect size is rather small despite adequate study power obtained.Nonetheless,operative position(supine or prone),puncture number,or tract dilatation size did not correlate with Hb difference.The mainstay of reducing bleeding in PCNL is still meticulous operative technique.Our study findings also suggest that PCNL can be safely done by urology trainees under supervision in suitably selected patient,without increasing risk of bleeding.

关键词： Percutaneous nephrolithotomy Predictive factor Risk factor Bleeding Blood loss

A Vertex Network Model of Arabidopsis Leaf Growth

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Communications on Applied Mathematics and Computation 2024年第1期6卷 454-488页

作者： Luke Andrejek Janet Best Ching-Shan chou Aman Husbands Department of Mathematics The Ohio State UniversityColumbusOHUSA Department of Biology The University of PennsylvaniaPhiladelphiaPAUSA

Biology provides many examples of complex systems whose properties allow organisms to develop in a highly reproducible,or robust,manner.One such system is the growth and development of flat leaves in Arabidopsis thaliana.This mechanistically challenging process results from multiple inputs including gene interactions,cellular geometry,growth rates,and coordinated cell divisions.To better understand how this complex genetic and cellular information controls leaf growth,we developed a mathematical model of flat leaf production.This two-dimensional model describes the gene interactions in a vertex network of cells which grow and divide according to physical forces and genetic information.Interestingly,the model predicts the presence of an unknown additional factor required for the formation of biologically realistic gene expression domains and iterative cell division.This two-dimensional model will form the basis for future studies into robustness of adaxial-abaxial patterning.

关键词： Robustness Adaxial-abaxial patterning Mathematical modeling Gene regulatory networks(GRNs) Transcription factors Small RNAs

Acquiring Weak Annotations for Tumor Localization in Temporal and Volumetric Data

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Machine Intelligence Research 2024年第2期21卷 318-330页

作者： Yu-cheng chou Bowen Li Deng-Ping Fan Alan Yuille Zongwei Zhou Department of Computer Science Johns Hopkins UniversityBaltimore 21218USA Computer Vision Lab ETH ZurichZurich 8001Switzerland

Creating large-scale and well-annotated datasets to train AI algorithms is crucial for automated tumor detection and localization.However,with limited resources,it is challenging to determine the best type of annotations when annotating massive amounts of unlabeled data.To address this issue,we focus on polyps in colonoscopy videos and pancreatic tumors in abdominal CT scans;Both applications require significant effort and time for pixel-wise annotation due to the high dimensional nature of the data,involving either temporary or spatial dimensions.In this paper,we develop a new annotation strategy,termed Drag&Drop,which simplifies the annotation process to drag and drop.This annotation strategy is more efficient,particularly for temporal and volumetric imaging,than other types of weak annotations,such as per-pixel,bounding boxes,scribbles,ellipses and points.Furthermore,to exploit our Drag&Drop annotations,we develop a novel weakly supervised learning method based on the watershed algorithm.Experimental results show that our method achieves better detection and localization performance than alternative weak annotations and,more importantly,achieves similar performance to that trained on detailed per-pixel annotations.Interestingly,we find that,with limited resources,allocating weak annotations from a diverse patient population can foster models more robust to unseen images than allocating per-pixel annotations for a small set of images.In summary,this research proposes an efficient annotation strategy for tumor detection and localization that is less accurate than per-pixel annotations but useful for creating large-scale datasets for screening tumors in various medical modalities.

关键词： Weak annotation detection localization segmentation colonoscopy abdomen

AP4 induces JNK1 and a miR-22-3p/FOSL1 feed-forward loop to activate AP-1 and promote colorectal cancer metastasis

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Cancer Communications 2024年第3期44卷 433-437页

作者： Jinjiang chou Markus Kaller Matjaz Rokavec Fangteng Liu Heiko Hermeking Experimental and Molecular Pathology Institute of PathologyMedical FacultyLudwig-Maximilians-Universität MünchenMunichGermany German Cancer Consortium(DKTK) Partner siteMunichGermany German Cancer Research Center(DKFZ) HeidelbergGermany

Dear Editor,Colorectal cancer(CRC)is the third most deadly can-cer worldwide[1].The mortality of CRC has remained high due to limited treatment options for metastatic CRC(mCRC)[2].Epithelial-mesenchymal transition(EMT)is an important contributor to mCRC[2].The c-MYC proto-oncogene(MYC)-induced transcription factor AP4(TFAP4/AP4)isadriverofEMT,therebypresumablyfacil-itates mCRC[3,4].The mitogen-activated protein kinase(MAPK)/c-JunN-terminalkinase(JNK)/activatorprotein-1(AP-1)pathway has been implicated in the regulation of EMT and mCRC[5].

关键词： JNK1 metastasis EMT

Catalytic behavior of Mo-Bi-Fe-Co-K-M-O(M=Ce,Gd,CeGd)catalysts for selective oxidation of isobutene

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Journal of Rare Earths 2024年第1期42卷 84-93,I0003页

作者： Qinghui Li Huahua Zhao Jian Yang Jun Zhao Liang Yan Huanling Song Lingjun chou State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

The further improvement of methacrolein(MAL)selectivity from isobutene(IB)oxidation is crucial and challenging.In this study,based on the typical Mo-Bi-Fe-Co-K-O mixed metal oxide,the rare earth element Gd-doped,Ce-doped and CeGd co-doped catalysts were prepared by co-precipitation strategy to increase the selectivity of MAL from 47.9%to 49.8%,64.2% and 68.6%,respectively.In order to elucidate in-depth the promoting effect of Ce and/or Gd,various characterizations were utilized including X-ray diffraction patterns(XRD),Raman,X-ray fluorescence spectrometry(XRF),X-ray photoelectron spectroscopy(XPS),O_(2)-temperature programmed desorption(O_(2)-TPD),H2-temperature programmed reduction(H2-TPR),CO_(2)-temperature programmed desorption(CO_(2)-TPD),IB-temperature programmed desorption(i-C4-TPD)and in-situ IB-Fourier transform infrared spectroscopy(IB-FTIR).Both Ce and Gd finely regulate the bulk and surface structure of the catalyst,thus altering the redox ability,oxygen mobility and storage ability and basicity.Compared with Ce,Gd addition slightly regulates the variation of Co^(2+)/Co^(3+)redox couples,greatly enhances the interaction among the components on the catalyst,thus only increases the content of surface oxygen species and has little effect on their mobility.While Cecontaining catalyst performs stronger oxygen storage and migration ability,thus leading to the overproduction of surface Odefectspecies,which are proposed to be the active sites for the production of MAL and COx.The CeGd co-doped catalyst possesses the proper content of surface Odefectspecies,thus exhibits much higher MAL selectivity.Moreover,the promoting mechanism of Ce and/or Gd over IB oxidation is proposed.Therefore,this work is helpful for understanding the influence of rare earth elements on the structure of mixed metal oxides and the olefin selective oxidation reaction.

关键词： Mixed metal oxide catalyst Rare earth element Isobutene Selective oxidation Methacrolein

Comprehensive analysis and mitigation strategies for safety issues of sodium-ion batteries

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Rare Metals 2024年第4期43卷 1343-1349页

作者： Tao Wei Xiao-Ling Xian Shi-Xue Dou Wei chen Shu-Lei chou Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou University Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou University Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation Campus

Sodium-ion batteries show great potential as an alternative energy storage system,but safety concerns remain a major hurdle to their mass adoption.This paper analyzes the key factors and mechanisms leading to safety issues,including thermal runaway,sodium dendrite,internal short circuits,and gas release.Several promising solutions are proposed,such as high-safety electrode materials in the cathode and anode,high-safety electrolytes,and external battery management systems.Here in also we emphasize the importance of selecting appropriate analysis methods and developing reliable failure models while suggesting advanced machine learning tools for analysis.With a comprehensive approach,this study offers valuable recommendations to optimize materials and solutions for improving the safety of sodium-ion batteries.

关键词： Sodium-ion batteries Safety issues Thermal runaway Sodium dendrites