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Photoluminescence upgradation of La_(2)mgTiO_(6):2%Dy^(3+) perovskite with monovalent(Li^(+)),divalent(Ba^(2+),Sr^(2+)) and trivalent(Bi^(3+),Sm^(3+))cation sensitization

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Journal of Rare Earths 2025年第1期43卷 47-56,I0002页

作者： V.P.Veena K.Arun c.K.Shilpa S.V.Jasira K.m.Nissamudeen School of Pure and Applied Physics Kannur UniversityPayyanur CampusEdatKannurKrala67 India Department of Nanoscience and Nanotechnology Kannur UniversityPayyanur CampusEdatkannurKerala670327India

Nano phosphors of 2%Dy^(3+)(wt%)doped La_(2)mgTiO_(6) and monovalent/divalent/trivalent co-doped La_(1.98)Dy_(0.02)mgTiO_(6):x%A^(y+)(A^(y+):Li+,Ba^(2+),Sr^(2+),Bi^(3+),and Sm^(3+);0≤x≤2 wt%)were synthesized by combustion *** the XRD data,it is deduced that an increase in the valency of co-dopant increases the crystallinity of the double perovskite orthorhombic nanocrystal *** an increase in co-dopant size,an elevation in optical bandgap is visible with the highest bandgap of 3.835 eV for Bi^(3+).The photo-absorption is monotonically broadened for Sr^(2+),Sm^(3+),and Li+around 200-450 ***351 nm,Dy^(3+)triggered lattice shows major characteristic emission peaks at 480 nm(^(4)F_(9/2)→^(6)H_(15/2)),574 nm(^(4)F_(9/2)→^(6)H_(13/2)),and 670 nm(^(4)F_(9/2)→^(6)H_(11/2)).leading to near white light emission with cIE coordinates(0.341,0.376).Upon co-doping,the PL intensity is significantly increased with maximum emission for trivalent Sm^(3+),followed by divalent Sr^(2+)and monovalent Li+*** increasing excitation wavelength,Sr^(2+)shows a dominated output and it is found that divalent Sr^(2+)is a potential codopant that could enhance luminescence intensity up to 6 times with a Sr^(2+)→Dy^(3+)energy transfer efficiency of 86%.It is specified that the cIE coordinates of Li+co-doped samples show ideal white emission with color coordinates(0.333,0.336).The concluding outcomes signify the noblest rare earth Sm^(3+)co-doping and thus Sm^(3+)→Dy^(3+)energy transfer mechanism is discussed in detail.

关键词： Photoluminescence Perovskite WLED co-doping Rareearths

Effect of divalent cations(co^(2+) and Ni^(2+)) on microstructure,physical properties and application of NdFeO_(3)

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Journal of Rare Earths 2025年第1期43卷 89-97,I0004页

作者： m.m.Arman materials Science Lab(1) Physics DepartmentFaculty of ScienceCairo UniversityGiza12613Egypt

The nanocrystalline samples Nd_(1-x)m_(x)FeO_(3)(x=0.0 and 0.1;m:co^(2+)and Ni^(2+))were prepared using the citrate combustion *** X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized in an orthorhombic *** particle size of Nd_(1-x)m_(x)FeO_(3) is in the range of 29-59 *** selected area electron diffraction(SAED)indicates the samples were prepared in a polycrystalline *** samples Nd_(1-x)m_(x)FeO_(3)(x=0.0 and 0.1;m:co^(2+)and Ni^(2+))have anti ferromagnetic *** Fe^(3+)spins are aligned antiparallel,forming the antiferromagnetic(AFm)properties,which are affected by many factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-moriya(D-m)*** doping of co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the magnetic properties of the NdFeO_(3).The saturation magnetization(ms)of Nd_(0.90)co_(0.10)FeO_(3) increases 1.8times more than that of NdFeO_(3).The exchange bias field(HEX)of the co-doped sample is two times greater than that of NdFeO_(3).The magnetic anisotropy constant(K)of the 10%co-doped sample increases by 11 factors compared to that of NdFeO_(3).The Tauc plot illustrates that the samples have a direct optical *** divalent cation substitution(co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recommendation of using the samples Nd_(0.90)co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from *** removal efficiencies of cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the samples NdFeO_(3),Nd_(0.90)co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),*** Freundlich isotherm mode is the best-fit model for NdFeO_(3) to adsorb cr6+ions from aqueous solutions.

关键词： Optical properties Nanoparticles magnetic properties Perovskites Removal efficiency Rareearths

Overcoming antibiotic-resistant Helicobacter pylori infection:current challenges and emerging approaches

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World Journal of Gastroenterology 2025年第10期31卷 7-29页

作者： Gabriel Reis rocha Fabian Fellipe Bueno Lemos Luis Guilherme de Oliveira Silva marcel Silva Luz Gabriel Lima correa Santos Samuel Luca rocha Pinheiro mariana Santos calmon Fabrício Freire de melo Instituto multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Recent studies have shown a noticeable increase in global Helicobacter pylori(***)resistance,with clarithromycin resistance surpassing 15%in various ***,inadequate epidemiological monitoring,especially in developing countries,and the absence of uniform testing methods lead to discrepancies between regions and a possible underestimation of resistance *** complexity of treating *** is driven by its highly dynamic genome,which is prone to frequent mutations contributing to phenotypical *** usual course of action in empirical treatment involves using a combination of various drugs simultaneously,leading to significant resistance selection pressure and potential side *** emergence of *** strains resistant to multiple drugs is closely tied to failures in first-line treatment,highlighting the need to prevent further resistance by using optimal initial empirical therapy or regimens guided by antibiotic susceptibility testing,requiring a collection of mixed samples and multiple isolates for accurate *** emergence of new treatments like potassium-competitive acid blockers offers a hopeful approach to decrease antimicrobial usage while still ensuring effectiveness in comparison to traditional therapies with proton pump ***,the use of probiotics is under investigation to identify specific strains and formulations that may mitigate therapy-associated adverse effects.

关键词： Helicobacter pylori Antibiotic resistance multidrug resistance Heteroresistance Empirical treatment Antimicrobial susceptibility testing

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： md Al Raihan c.Adam Dyker Department of chemistry University of New BrunswickFrederictonNB E3B 5A3Canada

As environmental concerns from fossil fuel consumption intensify,large-scale energy storage becomes imperative for the integration of renewable sources like wind,hydro,and solar with the electrical *** flow batteries,particularly those employing organic molecules,are positioned as a key technology for this *** review explores the growing field of symmetric organic redox flow batteries(ORFBs)within this *** traditional asymmetric designs based on unique active materials for each electrode,symmetric ORFBs involve a single bipolar species for both *** review highlights the benefits of a symmetric design,and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous *** providing a comprehensive overview of their cell cycling and performance characteristics,the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems,as are opportunities for future *** should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueousel ectrolyte

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

关键词： functionally graded material (FGm) pipe conveying fluid O175.2 porosity primary resonance retaining clip subcritical regime

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EmBASE,Ovid mEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Dynamics of air transport networks：A review from a complex systems perspective

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chinese Journal of Aeronautics 2017年第2期30卷 469-478页

作者： Luis E.c.rocha Department of Public Health Sciences Karolinska Institutet Stockholm 17177 Sweden Department of mathematics University of Namur 5000 Belgium

Air transport systems are highly dynamic at temporal scales from minutes to *** dynamic behavior not only characterizes the evolution of the system but also affect the system＇s *** the evolutionary mechanisms is thus fundamental in order to better design optimal air transport networks that benefits companies,passengers and the *** this review,we briefly present and discuss the state-of-the-art on time-evolving air transport *** distinguish the structural analysis of sequences of network snapshots,ideal for long-term network evolution（*** evolution）,and temporal paths,preferred for short-term dynamics（*** evolution）.We emphasize that most previous research focused on the first modeling approach（***-term） whereas only a few studies look at high-resolution temporal *** conclude the review highlighting that much research remains to be done,both to apply already available methods and to develop new measures for temporal paths on air transport *** particular,we identify that the study of delays,network resilience and optimization of resources（aircraft and crew） are critical topics.

关键词： Air transport Airport network complex network Dynamic network Temporal network

combined Effect of Honey from central West Brazil on Bacterial membrane Permeability

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Journal of Biosciences and medicines 2025年第1期13卷 316-337页

作者： mariana Lenina menezes Aleixo Joziane da cruz mendonça Rafael Bruno rocha Benevides Larissa maria Scalon Lemos carla Galbiati Graduate Program in Environmental Sciences (PPGcA) Office of Research and Graduate Studies State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil Faculty of Agrarian Sciences State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil Departament of Nursing Faculty of Health Sciences State University of Mato Grosso (UNEMAT) Cceres Mato Grosso Brazil

Honey, an apicultural product with a complex chemical composition, contains numerous bioactive compounds with potential antimicrobial effects. This study investigated the effect of Apis mellifera honey from Brazil’s central-West Region, combined with antibiotics, on bacterial membrane permeability, exploring the contributions of bioactive compounds and the botanical origin of honey. Six fresh Apis mellifera honey samples and their fractions (hexane and ethyl acetate) were analyzed, for a total of 18 samples. The bacteria Staphylococcus epidermidis, Helicobacter pylori and Enterococcus faecalis were used for antibacterial activity tests, which included minimum inhibitory concentration (mIc) determination and synergistic effect (checkerboard) assays. The total polyphenol and flavonoid contents were quantified, and the botanical origin was determined based on pollen analysis. The tested honey samples significantly affected bacterial membrane permeability when combined with rifampicin and clarithromycin. Although many honey-derived bioactive compounds, when isolated, did not exhibit significant activity against these bacteria, the additive or synergistic effect of multiple compounds acting on different targets appears to potentiate the antibacterial action. Descriptive statistical analysis, including means and 95% confidence intervals, confirmed the relevance of the findings. This study has provided an important discovery: Honey has an effect on bacterial membrane permeability, although the specific mechanisms involved in this process require further investigation.

关键词： Honey mechanism of Action Antibacterial Bacterial membrane Permeability Bioactive compounds

Honeycomb-spiderweb-inspired self-similar hybrid cellular structures for impact applications

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Defence Technology(防务技术) 2025年第1期43卷 182-200页

作者： K.Tewari m.K.Pandit m.m.mahapatra P.R.Budarapu School of mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar752050India

Inspired by nature's self-similar designs,novel honeycomb-spiderweb based self-similar hybrid cellular structures are proposed here for efficient energy absorption in impact *** energy absorption is enhanced by optimizing the geometry and topology for a given *** proposed hybrid cellular structure is arrived after a thorough analysis of topologically enhanced self-similar *** optimized cell designs are rigorously tested considering dynamic loads involving crush and high-velocity bullet ***,the influence of thickness,radial connectivity,and order of patterning at the unit cell level are also *** maximum crushing efficiency attained is found to be more than 95%,which is significantly higher than most existing traditional *** on,the first and second-order hierarchical self-similar unit cell designs developed during crush analysis are used to prepare the cores for sandwich *** tests are performed on the developed sandwich structures using the standard 9-mm *** influence of multistaging on impact resistance is also investigated by maintaining a constant total thickness and mass of the sandwich ***,in order to avoid layer-wise weak zones and hence,attain a uniform out-of-plane impact strength,off-setting the designs in each stage is *** sandwich structures with first and second-order self-similar hybrid cores are observed to withstand impact velocities as high as 170 m/s and 270 m/s,respectively.

关键词： Sandwich structures Honeycomb-spider web inspired Self-similar hierarchy crush analysis High-velocity impact Strong and weak zones multistaging