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Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey e.Miroshnichenko school of Physics and electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical engineering Rowan University school of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI H.GHANDVAR e.JUMAeV s.KHATIR T.CUONG-Le school of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词： Kinetic energy

Moisture effect on the combustion of a single copper concentrate particle in a flash smelting furnace

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 251-258页

作者： e.hassan Zaim s.H.Mansouri A.Arab solghar Department of Mechanical engineering School of Engineering Shahid Bahonar University Department of Mechanical engineering School of Engineering Vali-e-Asr University

A mathematical model has been presented to study the combustion of a single copper concentrate particle with high moisture content. By using the presented model, the effect of particle moisture content on particle temperature, sulfur oxidation, and combustion heat generation has been evaluated. The mineralogical composition of the commonly used concentrate at Khatoonabad flash smelting furnace has been used in this study. It was found that the particle moisture content is removed in the sub-second time range and thus the moisture has marginal impact on the variation of particle temperature and on the reaction rate when the gas temperature is assumed to be constant in the reaction shaft. When a concentrate with high moisture content is charged, the particle size enlargement due to the agglomeration of concentrate particles causes an abrupt fall in the particle reaction rate.

关键词： flash smelting furnaces copper smelting moisture combustion

economic Development through Medicinal and Aromatic Plants(MAPs) Cultivation in Hindu Kush Himalaya Mountains of District swat, Pakistan

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Journal of Mountain science 2015年第5期12卷 1292-1301页

作者： hassan sHeR Mary e. BARKWORTH Center for Plant sciences and Biodiversity University of Swat Intermountain Herbarium Department of Biology Utah State University

Poverty is pervasive in the swat Valley in northwestern Pakistan, and most people survive by farming small landholdings. However, many supplement their meager subsistence earnings by collecting and selling plant material for use in herbal medicine. This material is wild-harvested, but collectors seem not to fully appreciate the potential value of the plant material they collect nor the longterm impact their collection has on local plant populations. A model project supported by the International Food Policy Research Institute(IFPRI)persuaded small-scale farmers in four different villages to use some of their land for cultivating traditionally wild-harvested species of medicinal and aromatic plants(MAPs) with high market value. The farmers were provided seeds or rhizomes of five MAPs and asked to monitor their germination and growth on 25 m2 plots during a 12 month period. At the end of the study, growth and yield data from the four localities were compared and economic analyses conducted to determine the profitability of the species based on yields, prevailing market prices, and costs of production. Five of the cultivated species were subsequently marketed and their value evaluated:sesamum indicum, Linum usitatissimum, Ocimum basilicum, Nigella sativa and Viola pilosa. The MAPs V. pilosa and O. basilicum were the most profitable,whereas Nigella sativa was the least profitable because of its low germination rate. The net income from all but Nigella was higher than that would have been earned by planting the same area with the predominant cereals or tomatoes. In addition to demonstrating the feasibility and financial benefits of cultivating MAPs as a cash crop, this model study identified a number of additional steps that would increase the benefits of MAPs cultivation in this area.A combination of specialized education, market infrastructure development and a small loans program would enable farmers to increase their agricultural income without damaging the area's pl

关键词： Biological diversity Medicinal plant Aromatic plant Agriculture productivity Traditionalcrops economic analysis Himalaya Mountains

A method for matching response spectra of endurance time excitations via the Fourier transform

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earthquake engineering and engineering Vibration 2020年第3期19卷 637-648页

作者： Mohammadreza Mashayekhi Homayoon eestekanchi hassan Vafai Department of Civil engineering Sharif University of TechnologyTehranIran

The endurance time(eT)method is a dynamic analysis in which structures are subjected to intensifying excitations,also known as eT excitation functions(eTeF).The eT method is a tool for structural response *** main advantage of the eT method over conventional approaches is its much lower demand for computational *** concept of acceleration spectra is used in generating existing *** is expected that eTeF acceleration spectra increase consistently with time and remain proportional to a target *** unconstrained optimization is commonly used to generate *** new eTeFs is a complicated time-consuming mathematical *** the target acceleration spectrum changes,new eTeFs must be *** study intends to modify existing eTeFs to be compatible with a desired acceleration *** process,called spectral matching,obviates the need for using the complicated generating procedure in simulating new *** spectral matching is introduced in this paper for the first time.A Fourier-based method for eTeFs spectral matching is *** algorithm is then applied in a case *** are presented to prove the efficiency of the algorithm.

关键词： spectrum. excitation acceleration

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa M.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

FORCeD OsCILLATION OF seCOND ORDeR DIFFeReNTIAL eQUATIONs WITH MIXeD NONLINeARITIes

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Acta Mathematica scientia 2011年第2期31卷 613-626页

作者： Taher s. hassan Lynn erbe Allan Peterson Department of Mathematics Faculty of Science Mansoura University Department of Mathematics University of Nebraska-Lincoln

This article is concerned with the oscillation of the forced second order differ- ential equation with mixed nonlinearities（a（t）（x＇（t））γ）＇＋po（t）xγ（go（t））＋n∑t=1pi（t）｜x（gi（t））｜αi sgn x（gi（t））=e（t）,where γ is a quotient of odd positive integers αi〉0,i=1,2 ……n,a,e,and pi ∈ C（[0,∞）R）,a（t）〉0,gi：R→R are positive continuous functions on R with lim gi （t）=∞,i=0,1,……,n. Our results generalize and improve the results in a recent article by sun and Wong[29].

关键词： Oscillation functional differentail equations second order

Constrained bilinear control problem： Application to a cancer chemotherapy model

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International Journal of Biomathematics 2017年第4期10卷 189-209页

作者： e1 hassan Zerrik Nihale e1 Boukhari MA Cs Team Faculty of Sciences Moulay Ismail University Meknes Morocco

The aim of this paper is to investigate the optimal control problem for finite-dimensional bilinear systems and its application to a chemotherapy model. We characterize an opti- mal control that minimizes a quadratic cost functional in two cases of constrained admis- sible controls, then we give sufficient conditions for the uniqueness of such a control, and we derive useful algorithms for the computation of the optimal control. The established results are applied to a cancer chemotherapy bilinear model in order to simulate the opti- mal treatment protocol using two different approaches： one based on a limited instant toxicity, and the other on a limited cumulative toxicity along the therapy session.

关键词： Bilinear systems optimal control chemotherapy instant toxicity cumulativetoxicity.

Insights into CYP2B6-mediated drug–drug interactions

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Acta Pharmaceutica sinica B 2016年第5期6卷 413-425页

作者： William D.Hedrich Hazem e.hassan Hongbing Wang Department of Pharmaceutical sciences University of Maryland School of Pharmacy

Mounting evidence demonstrates that CYP2B6 plays a much larger role in human drug metabolism than was previously *** discovery of multiple important substrates of CYP2B6 as well as polymorphic differences has sparked increasing interest in the genetic and xenobiotic factors contributing to the expression and function of the *** expression of CYP2B6 is regulated primarily by the xenobiotic receptors constitutive androstane receptor(CAR) and pregnane X receptor(PXR) in the *** addition to CYP2B6,these receptors also mediate the inductive expression of CYP3A4,and a number of important phase II enzymes and drug ***2B6 has been demonstrated to play a role in the metabolism of 2%–10% of clinically used drugs including widely used antineoplastic agents cyclophosphamide and ifosfamide,anesthetics propofol and ketamine,synthetic opioids pethidine and methadone,and the antiretrovirals nevirapine and efavirenz,among *** inter-individual variability in the expression and function of the human CYP2B6 gene exists and can result in altered clinical outcomes in patients receiving treatment with CYP2B6-substrate *** variances arise from a number of sources including genetic polymorphism,and xenobiotic *** this review,we will provide an overview of the key players in CYP2B6 expression and function and highlight recent advances made in assessing clinical ramifications of important CYP2B6-mediated drug–drug interactions.

关键词： CYP2B6 CAR PXR Polymorphism Drug–drug interaction Cyclophosphamide efavirenz