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In situ magnesium calcium phosphate cements formation: From one pot powders precursors synthesis to in vitro investigations

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Bioactive materials 2020年第3期5卷 644-658页

作者： m.a.goldberg P.A.Krohicheva A.S.Fomin D.R.Khairutdinova O.S.Antonova A.S.Baikin V.V.Smirnov A.A.Fomina A.V.Leonov I.V.mikheev N.S.Sergeeva S.A.Akhmedova S.m.Barinov V.S.Komlev A.A.Baikov Institute of metallurgy and materials Science Russian Academy of Sciences119334Leninsky av49MoscowRussian Federation m.V.Lomonosov moscow State University Department of Chemistry119991Leninskie Gory1MoscowRussian Federation Federal State Budgetary Institution National medical Research Radiological Center of the ministry of Health of the Russian Federation 1252842nd Botkinsky pass.3MoscowRussian Federation

Calcium phosphate cements are of great interest for researchers and their applications in medical practice ***,they have a number of drawbacks including the insufficient level of mechanical properties and low degradation ***(mgNH4PO4)-based cements,which grew in popularity in recent years,despite their neutral pH and acceptable mechanical performance,release undesirable NH4+ions during their *** issue could be avoided by replacement of ammonia ions in the cement liquid with sodium,however,such cements have a pH values of 9–10,leading to ***,the main goal of this investigation is to optimize the composition of cements to achieve the combination of desirable properties:neutral pH,sufficient mechanical properties,and the absence of cytotoxicity,applying Na2HPO4-based cement *** this purpose,cement powders precursors in the CaO-mgO-P2O5 system were synthesized by one-pot process in a wide composition range,and their properties were *** optimal performance was observed for the cements with(Ca+mg)/P ratio of 1.67,which are characterized by newberyite phase formation during setting reaction,pH values close to 7,sufficient compressive strength up to 22±3 mPa(for 20 mol.%of mg),dense microstructure and adequate matrix properties of the *** set of features make those materials promising candidates for medical applications.

关键词： magnesium calcium phosphate cement Stanfieldite Whitlockite Newberyite Brushite In vitro investigations

Recovery rates of persistent post-COVID-19 olfactory dysfunction using psychophysical assessment:A longitudinal cohort study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 79-87页

作者： Jeremy P.Tervo Patricia T.Jacobson Brandon J.Vilarello Tiana m.Saak Francesco F.Caruana Liam W.Gallagher Joseph B.Gary David A.Gudis Paule V.Joseph D.P.Devanand Terry E.goldberg Jonathan B.Overdevest Columbia University Vagelos College of Physicians and Surgeons New YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery New York-Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery University of PittsburghPittsburghPennsylvaniaUSA Department of Otolaryngology-Head and Neck Surgery University of MinnesotaMinneapolisMinnesotaUSA National Institute of Alcohol Abuse and Alcoholism Section of Sensory Science and Metabolism&National Institute of Nursing ResearchBethesdaMarylandUSA New York-Presbyterian/Columbia University Irving medical Center New YorkNew YorkUSA

Objectives:Persistent olfactory dysfunction(OD)following loss of smell associated with SARS-CoV-2 infection is a major feature of long *** on the prevalence of persistent OD predominantly rely on self-reported olfactory *** studies have tracked longitudinal rates of recovery using psychophysical assessment among patients presenting for evaluation of persistent OD beyond a window of acute *** anchored in standardized testing methods are needed to counsel patients who fail to acutely regain their sense of *** study aims to quantify the degree of persistent OD in post-COVID-19 patients who experience subjective and psychophysical ***:We grouped participants presenting for OD evaluation into cohorts based on both subjective and psychophysical olfactory status at a baseline assessment and assessed their olfactory abilities with a visual analogue scale and the Sniffin'Sticks extended test at baseline and 1-year time *** had confirmed a history of COVID-19 by lab evaluation or clinical diagnosis if lab evaluation was not ***:Baseline olfactory evaluation was completed by 122 participants,53 of whom completed the 1-year follow-up *** participants presenting with perceived OD,74.5%had confirmed psychophysical OD at baseline,with 55.1%at 1-year *** had reliable trends in self-rated versus psychophysically tested olfactory function at both time *** total threshold,discrimination,and identification(TDI)score improved by+3.25 points in the cohort with psychophysical OD(p=0.0005),with this improvement largely attributable to an increase in median threshold scores(+2.75 points;p=0.0004).Conclusions:OD persists in a significant number of patients who fail to acutely recovery their sense of smell after COVID-19,with many demonstrating lingering deficits at *** in threshold,but not discrimination or identification,most significantly mediate improvement

关键词： long COVID olfaction post-COVID condition smell dysfunction

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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跨代际社区可帮助老年人对抗孤独

商业周刊（中文版） 2024年第14期 42-44页

作者： Bridget goldberg 程玺不详

英格兰切斯特的Belong是一个为痴呆症患者提供支持的综合性住宅区,一楼设有面向婴儿和学龄前儿童的幼儿园。这种布局让当今最年轻的一代有机会与年长居民互动,反之亦然,由此营造出了一个展现完整生命周期的生动场景。Belong的居民被称... 详细信息

英格兰切斯特的Belong是一个为痴呆症患者提供支持的综合性住宅区,一楼设有面向婴儿和学龄前儿童的幼儿园。这种布局让当今最年轻的一代有机会与年长居民互动,反之亦然,由此营造出了一个展现完整生命周期的生动场景。Belong的居民被称为“老朋友”,他们居住在24小时护理中心或独立生活的公寓里,几乎随时可以下楼看望孩子们。

关键词：护理中心年轻的一代学龄前儿童痴呆症切斯特生命周期老年人住宅区

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： Semiconductor TiO_(2) Rare earths Congo red methylene blue Solar spectrum Photodegradation

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** Hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie E Ghasemian Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied mathematics and mechanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHmAN m.TURKYILmAZOGLU Z.mUSHTAQ Department of mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,m=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number