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Multi-layer perceptron-based data-driven multiscale modelling of granular materials with a novel Frobenius norm-based internal variable

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Journal of Rock Mechanics and Geotechnical engineering 2024年第6期16卷 2198-2218页

作者： Mengqi Wang Y.t.Feng Shaoheng Guan tongming Qu Zienkiewicz Centre for Computational engineering Faculty of Science and EngineeringSwansea UniversitySwanseaWalesSA18EPUK Institute of theoretical and Computational Physics Graz University of TechnologyGraz8010Austria Department of Civil and environmental engineering Hong Kong University of Science and TechnologyClearwater BayKowloonHong KongChina

One objective of developing machine learning(ML)-based material models is to integrate them with well-established numerical methods to solve boundary value problems(BVPs).In the family of ML models,recurrent neural networks(RNNs)have been extensively applied to capture history-dependent constitutive responses of granular materials,but these multiple-step-based neural networks are neither sufficiently efficient nor aligned with the standard finite element method(FeM).Single-step-based neural networks like the multi-layer perceptron(MLP)are an alternative to bypass the above issues but have to introduce some internal variables to encode complex loading *** this work,one novel Frobenius norm-based internal variable,together with the Fourier layer and residual architectureenhanced MLP model,is crafted to replicate the history-dependent constitutive features of representative volume element(RVe)for granular *** obtained ML models are then seamlessly embedded into the FeM to solve the BVP of a biaxial compression case and a rigid strip footing *** obtained solutions are comparable to results from the FeM-DeM multiscale modelling but achieve significantly improved *** results demonstrate the applicability of the proposed internal variable in enabling MLP to capture highly nonlinear constitutive responses of granular materials.

关键词： Granular materials History-dependence Multi-layer perceptron(MLP) Discrete element method FeM-DeM Machine learning

enhanced and asymmetric signatures of hybridization at climatic margins: evidence from closely related dioecious fig species

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Plant Diversity 2024年第2期46卷 181-193页

作者： Jian-Feng Huang Clive t.Darwell Yan-Qiong Peng CAS Key Laboratory of tropical Forest ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China National Center for Genetic engineering and Biotechnology(BIOteC) 113 Thailand Science ParkPhahonyothin RoadKhlong NuengKhlong LuangPathum Thani 12120Thailand

Hybridization plays a significant role in biological evolution. However, it is not clear whether ecological contingency differentially influences likelihood of hybridization, particularly at ecological margins where parental species may exhibit reduced fitnesses. Moreover, it is unknown whether future ecosystem change will increase the prevalence of hybridization. Ficus heterostyla and F. squamosa are closely related species co-distributed from southern thailand to southwest China where hybridization, yielding viable seeds, has been documented. As a robust test of ecological factors driving hybridization, we investigated spatial hybridization signatures based on nuclear microsatellites from extensive population sampling across a widespread contact range. Both species showed high population differentiation and strong patterns of isolation by distance. Admixture estimates exposed asymmetric interspecific gene *** of hybridization increase significantly towards higher latitude zones, peaking at the northern climatic margins. Geographic variation in reproductive phenology combined with ecologically challenging marginal habitats may promote this phenomenon. Our work is a first systematic evaluation of such patterns in a comprehensive, latitudinally-based clinal context, and indicates that tendency to hybridize appears strongly influenced by environmental conditions. Moreover, that future climate change scenarios will likely alter and possibly augment cases of hybridization at ecosystem scales.

关键词： Hybridization Heterospecific visitation Fig Pollinator wasp Asymmetric gene flow

Analysis of strong decays of SU(3)partners ofΩ(2012)baryon

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Chinese Physics C 2024年第8期48卷 34-41页

作者： t.M.Aliev S.Bilmis M.Savci Department of Physics Middle East Technical UniversityAnkara 06800Turkey tUBItAK ULAKBIM Ankara 06510Turkey

We estimate the coupling constants and decay widths of the SU(3)partners of theΩ(2012)hyperon,as discovered by the BeLLe Collaboration,using the distribution amplitudes of the octet baryons within the light cone sum rules *** study includes a comparison of the obtained results for the relevant decay widths with those derived within the framework of the flavor SU(3)*** observe a good agreement between the predictions of both ***,our result on the decay width ofΩ→ΞK is compatible with the existing experimental result within the uncertainties of the model *** results can provide helpful insights for determining the nature of the SU(3)partners of theΩ(2012)baryon.

关键词： coupling constants light cone sum rule hyperon

evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods

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earthquake engineering and engineering Vibration 2024年第3期23卷 713-726页

作者： M.A.Najafgholipour S.Heidarian Radbakhsh e.erfani Department of Civil and environmental engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

this paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the OpenSees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis

emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e Vijayatha V Ramasubramanian S thiyagarajan P Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

A new method for precise optical measurements of the sub-micron height of levitation of droplet clusters

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Particuology 2024年第4期87卷 173-178页

作者： Alexander A.Fedorets eduard e.Kolmakov Leonid A.Dombrovsky University of tyumen 6 Volodarskogo StTyumen625003Russia engineering Faculty Ariel UniversityP0.B.3407000ArielIsrael Joint Institute for High temperatures 17A Krasnokazarmennaya StMoscow111116Russia

Droplet clusters levitating over the locally heated water surface are considered a very promising phe-nomenon of microfluidics for the potential use of the droplets as unique microreactors for microbio-logical experiments.A new optical method is suggested for precise measurements of the sub-micron levitation height of single *** method is based on the analysis of variable colors of the inter-ference halo around the *** the first time,it is possible to measure the extremely low downward velocity of droplets,which grow due to steam *** velocity was found to be 5-8 nm/*** height of the levitation of various droplets just before their coalescence with a layer of water was also *** measurements might be used for the verification of sophisticated models for the droplet levitation to be developed for a very thin layer of humid air under the droplet when the Knudsen effect should be taken into account.

关键词： Precise measurements Interferometric method Droplet cluster Levitation height

Highly Defective Dark tiO_(2) Modified with Pt: effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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transactions of tianjin University 2024年第2期30卷 198-209页

作者： e.D.Fakhrutdinova O.A.Reutova t.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus D.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi National Research tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

the study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. the sample featured a high content of single-atom species and subnano-sized Pt clusters. the X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the tiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. the 0.5Pt(C)/tiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)tiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

the Spectrum of Nail Disorders in Patients with end-Stage Renal Disease Undergoing Conservative treatment: A Case-Control Study

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International Journal of Dermatology and Venereology 2024年第3期7卷 150-154页

作者： Shigidi M.M.t. Department of Internal Medicine College of Medicine Jouf University Al Jouf 72388 Saudi Arabia Nephrology Division Department of Medicine Baraha Medical City North Khartoum State Khartoum 13311 Sudan

Objective: Various nail disorders have been reported in patients with chronic kidney disease. However, few studies have investigated nail disorders in patients with advanced chronic kidney disease. this study focused on nail disorders seen in patients with end-stage renal disease (eSRD) undergoing conservative treatment. Methods: A case-control study was conducted at Baraha Medical City in Khartoum State, Sudan. Data on patients with eSRD who were on conservative treatment and presented for follow-up between March and September 2021 were collected. Patients' demographic features, nail findings on clinical examination, and laboratory results were recorded. the obtained data were compared with those on age- and sex-matched healthy individuals from the general population. the chi-square test and Student t test were performed to analyze categorical and numerical variables, respectively. Results: Data on 78 patients with eSRD were studied. their mean age was 54.6 ± 17.6 years, and 45 (57.7%) were men. these patients were compared with 129 controls. Nail disorders were seen in 65 (83.3%) eSRD patients and 86 (66.6%) controls (P = 0.009). Patients with eSRD were found to be at increased relative risk of developing a wide spectrum of nail disorders. An absent lunula, half-and-half nails, nail dystrophy, terry's nails, onychomycosis, and koilonychia were the most common disorders and were seen in 44 (56.4%), 13 (16.7%), 10 (12.8%), 9 (11.5%), 6 (7.7%), and 5 (6.4%) patients, respectively. Patients with eSRD had a statistically significant risk of developing above diseases (all P the current study demonstrated a wide spectrum of nail disorders in patients with eSRD undergoing conservative treatment. Further studies are essential to understand their pathogenesis. © 2024 Hospital for Skin Diseases (Institute of Dermatology), Chinese Academy of Medical Sciences, and Chinese Medical Association, published by Wolters Kluwer, Inc.

关键词： chronic kidney disease disease spectrum end-stage renal disease nail disorders

Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes

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Asian pacific Journal of Reproduction 2024年第5期13卷 219-227页

作者： Vu D Hop An M Cuong Phi t t Anh Nguyen t L Huong Le Hoang Nguyen V Hanh Assisted Reproductive technology Centre Tam Anh General HospitalHanoiVietnam Institute of Biotechnology Vietnam Academy of Science and TechnologyHanoiVietnam

Objective:to determine the relationship between the early embryo viability assessment(eeVA)and blastocyst morphological parameters and pregnancy ***:this retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June *** eeVA system produced an eeVA score from e1(best)to e5(worse)for the potential of blastocyst *** morphology was *** association between the eeVA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating ***:the inner cell mass A(ICM A),trophectoderm A(te A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the eeVA *** adjusted odd ratio(aOR)(e5 vs e1)was 0.3 for ICM A,0.174 for te A and 0.210 for BL3,4,5,6,7(all Pesting a significant association between lower eeVA scores and improved embryo *** implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the eeVA *** aOR of e5 vs e1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(Pthere were associations between blastocyst morphology,pregnancy outcome and eeVA *** good blastocyst morphology and pregnancy outcomes are higher with lower the eeVA score.

关键词： Automated embryo assessment Blastocyst early embryo viability assessment Genea embryo review incubator