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On self-affine tiles that are homeomorphic to a ball

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Science China mathematics 2024年第1期67卷 45-76页

作者： Jorg m.thuswaldner Shu-Qin Zhang mathematics and Statistics University of LeobenLeoben 8700Austria School of mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Let m be a 3×3 integer matrix which is expanding in the sense that each of its eigenvalues is greater than 1 in modulus and let D?Z^(3)be a digit set containing|det m|*** the unique nonempty compact set t=t(m,D)defined by the set equation mt=t+D is called an integral self-affine tile if its interior is *** D is of the form D={0,v,...,(|det m|-1)v},we say that t has a collinear digit *** present paper is devoted to the topology of integral self-affine tiles with collinear digit *** particular,we prove that a large class of these tiles is homeomorphic to a closed 3-dimensional ***,we show that in this case,t carries a natural CW complex structure that is defined in terms of the intersections of t with its neighbors in the lattice tiling{t+z:z∈Z^(3)}induced by *** CW complex structure is isomorphic to the CW complex defined by the truncated octahedron.

关键词： self-afine sets tiles and tilings low-dimensional topology truncated octahedron

Development of a handheld diffuse optical breast cancer assessment probe

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 31-40页

作者： majid Shokoufi farid Golnaraghi School of mechatronic Systems Engineering Simon Fraser University 250-13450102 Avenue SurreyCanadaBC V3T 0A3

Diffuse Optical Spectroscopy(DOS)is a promising non-invasive and non-ionizing technique for breast anomaly *** this study,we have developed a new handheld DOS probe to measure optical properties of breast *** the proposed probe,the breast tissue is illuminated with four near infrared(NIR)wavelengths light emitting diodes(LED),which are encapsulated in a package(eLEDs),and two PIN photodiodes measure the intensity of the scattered photons at two di®erent *** proposed technique of using eLEDs is introduced,in order to have a multi-wavelength pointed-beam illumination source instead of using the laser-coupledflberoptic technique,which increases the complexity,size,and cost of the *** the fact that the proposed technique miniaturizes the probe and reduces the complexity of the DOS,the study proves that it is accurate and reliable in measuring optical properties of the *** measurements are performed at the rate of 10 Hz which is suitable for dynamic measurement of biological activity,*** multi-spectral evaluation algorithm is used to reconstruct four main absorber concentrations in the breast including oxy-hemoglobin(cHb),deoxy-hemoglobin(cHbO_(2)),water(cH2O),fat(cFat),and average scattering coeficient of the medium,as well as concentration changes in Hb(cHb)and HbO_(2)(cHbO_(2)).Although the probe is designed for breast cancer diagnosis,it can be used in a wide range of applications for both static and dynamic measurements such as functional brain imaging.A series of phantoms,comprised of Delrinr,Intralipidr,Piercetm and Black ink,are used to verify performance of the *** probe will be tested on human subjects,in-vivo,in the next phase.

关键词： Breast cancer diffuse optical spectroscopy intrinsic optical contrast hemoglobin concentration optical breast phantom

miniSCIDOm: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino m.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz m.Schneider U.Schramm m.E.P.Umlandt K.Zeil t.Ziegler J.metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOm detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).the detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Al-Ca-Cu三元合金体系中与铝平衡的金属间化合物

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transactions of Nonferrous metals Society of China 2024年第5期34卷 1380-1392页

作者： t.K.AKOPYAN t.A.SVIRIDOVA N.A.BELOV N.V.LEtYAGIN A.V.KOROtItSKIY National University of Science and technology mISiS 4 Leninsky pr.Moscow 119049Russia

对三元Al-Ca-Cu合金体系中与铝固溶体平衡的(Al,Cu)_(4)Ca、Al_(27)Ca_(3)Cu_(7)和Al_(8)CaCu_(4)金属间化合物的结构和性能进行全面分析。基于Al4Ca相中部分Al原子被Cu取代,将(Al,Cu)_(4)Ca金属间化合物视为线性化合物。化合物中铜的... 详细信息

对三元Al-Ca-Cu合金体系中与铝固溶体平衡的(Al,Cu)_(4)Ca、Al_(27)Ca_(3)Cu_(7)和Al_(8)CaCu_(4)金属间化合物的结构和性能进行全面分析。基于Al4Ca相中部分Al原子被Cu取代,将(Al,Cu)_(4)Ca金属间化合物视为线性化合物。化合物中铜的溶解度达到10 at.%(19 wt.%),导致化合物的晶格结构、物理和力学性能发生显著变化。例如,化合物的密度从2.22 g/cm^(3)增加到2.79 g/cm^(3),显微硬度从HV 180增加到HV 250。将Al_(27)Ca_(3)Cu_(7)相视为具有严格化学计量比和BaHg11型初始晶体结构的三元化合物,其空间群为Pm3m,晶格参数为8.514Å,密度为3.45 g/cm^(3)。Al_(8)CaCu_(4)相也是严格化学计量比的三元化合物,具有mn_(12)th型晶格结构,最高的显微硬度(HV 505)和密度(4.57 g/cm^(3))。属于二元(Al)+(Al,Cu)_(4)Ca相场和准二元(Al)+Al_(27)Ca_(3)Cu_(7)截面的合金,有前景作为新型天然铝基复合材料的基材。

关键词：金属间化合物 Al-Ca合金显微组织晶体结构物理性能力学性能

Fire resistance evaluation through synthetic fire tests and generative adversarial networks

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： Aybike Özyüksel Çiftçioğlu m.Z.Naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

this paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,Light Gradient Boosting machine,Categorical Boosting Algorithm,Support Vector Regression,Random Forest,Decision tree,multiple Linear Regression,Polynomial Regression,Support Vector machine,Kernel Support Vector machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

Kinematic analysis of flexible bipedal robotic systems

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.FAZEL A.m.SHAFEI S.R.NEKOO Department of mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Advances in magnesium-containing bioceramics for bone repair

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Biomaterials translational 2024年第1期5卷 3-20页

作者： Qi L. Zhao t. Yan J. Ge W. Jiang W. Wang J. Gholipourmalekabadi m. Lin K. Wang X. Zhang L. Department of Oral and Cranio-maxillofacial Surgery Shanghai Ninth People’s Hospital College of Stomatology Shanghai Jiao Tong University School of Medicine National Clinical Research Center for Oral Diseases Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology Shanghai China Department’s Education Deputy Department of Medical Biotechnology Iran University of Medical Sciences Tehran Iran Institute of translational medicine Shanghai University Organoid Research Center Shanghai University Shanghai China

Reconstruction of bone defects or fractures caused by ageing, trauma and tumour resection is still a great challenge in clinical treatment. Although autologous bone graft is considered as gold standard, the source of natural bone is limited. In recent years, regenerative therapy based on bioactive materials has been proposed for bone reconstruction. Specially, numerous studies have indicated that bioactive ceramics including silicate and phosphate bioceramics exhibit excellent osteoinductivity and osteoconductivity, further promote bone regeneration. In addition, magnesium (mg) element, as an indispensable mineral element, plays a vital role in promoting bone mineralisation and formation. In this review, different types of mg-containing bioceramics including mg-containing calcium phosphate-based bioceramics (such as mg-hydroxyapatite, mg-biphasic calcium phosphate), mg-containing calcium silicate-based bioceramics (such as mg2SiO4, Ca2mgSi2O7and mg-doped bioglass), mg-based biocements, mg-containing metal/polymer-bioceramic composites were systematacially summarised. Additionally, the fabrication technologies and their materiobiological effects were deeply discussed, Clinical applications and perspectives of magnesium-containing bioceramics for bone repair are highlighted. Overall, mg-containing bioceramics are regarded as regenerative therapy with their optimised performance. Furthermore, more in-depth two-way researches on their performance and structure are essential to satisfy their clinical needs. © 2024, Chinese medical multimedia Press Co Ltd. All rights reserved.

关键词： bioactive ions bioceramics bone repair magnesium osteoconductivity

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials Science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do Rego A.S.Viana A.J.S.Fernandes A.J.Fielding R.A.Videira m.C.Oliveira CQ-VR and Chemistry Department University of Trás-os-Montes e Alto Douro BSIRG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUImtE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization NmR XPS Hydrophilic carbon Paramagnetic

Protocol for the development and validation of a clinical measurement tool for fear of disease progression and recurrence in cardiac patients

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Chronic Diseases and translational medicine 2024年第3期10卷 195-204页

作者： Sarah t.Clarke michael Le Grande Barbara m.murphy Robert Hester Alun C.Jackson melbourne School of Psychological Sciences University of MelbourneParkvilleVictoriaAustralia Australian Centre for Heart Health MelbourneVictoriaAustralia Centre on Behavioral Health University of Hong KongPokfulamHong KongChina

Introduction: One in two cardiac patients fear having another heart event or their heart condition getting worse. Research in other chronic illnesses demonstrates that screening for fear of progression and recurrence is vital for adequately addressing such concerns in clinical care. the current project aims to develop and validate a measure for fear of progression and recurrence in cardiac ***: the Fear of Cardiac Recurrence and Progression Scale (FCRP) will be developed through a multistep process. An initial item pool will be generated through a review of the literature and existing measures and consultation with and feedback from key informants. the item pool will be tested in a sample of over 250 adults who have ever had an acute coronary event, undergone cardiac surgery, or a chronic cardiac condition. Exploratory factor analysis will be used to identify the underlying factors, and Rasch analysis will be used to reduce the number of items. A short form version of the FCRP will be developed for use as a brief screening tool, informed by clinical relevance and Rasch psychometric ***: While many cardiac patients experience fears related to the progression or recurrence of their illness, there remains the need for a validated tool with which these concerns can be identified and measured. It is expected that the design and validation of the FCRP will aid identification of cardiac patients suffering from clinically significant levels of fear of progression and recurrence and facilitate the design of tailored psychological interventions to target these fears.

关键词： anxiety cardiac anxiety cardiac recovery cardiac rehabilitation depression fear of progression fear of recurrence psychological measurement psychosocial screening