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Background: Ultracongruent (UC) total knee replacement (TKR) designs, serving as alternatives to posterior stabilized (PS) and cruciate retaining (CR) designs, lack conclusive evidence regarding posterior femoral rollback. This study aimed to compare intraoperative posterior femoral rollback and maximal knee flexion between UC and PS inserts, addressing the paucity of literature on femoral rollback achieved with UC designs in total knee replacement. Methods: A consecutive cohort of 20 patients undergoing robotic-assisted primary total knee replacement, posterior femoral rollback and maximal intraoperative knee flexion were assessed. Robotic imaging at varying flexion angles (0°, 45°, 90°, and 120°) was conducted after implanting femoral and tibial components with Ultracongruent and Posterior-Stabilized trial inserts. Femoral contact on the tibia was estimated as a percentage of the sagittal dimension of the tibial component with 0 representing the anterior edge and 100 representing the posterior edge of the tibial component. Results: In extension, UC inserts exhibited a statistically significant posterior contact point versus PS inserts (56.3 + 4.3 vs 53.5 + 5.3, p = 0.003). Between 0 and 45° flexion, 13 of 20 UC inserts showed a paradoxical anterior translation exceeding 5%, unlike the PS group. At 90° flexion, both displayed consistent posterior femoral rollback, with PS inserts having a more posterior contact point (63.5 + 6.2 vs 67.2 + 5.1, p =.008). At 120° flexion, rollback was similar (70.1 + 8.4 vs 71.3 + 8.4, p = 0.128). Mean maximal flexion was 130° (SD = 6.87) and 133° (SD = 6.72) for UC and PS inserts, respectively (p = 0.0001). Conclusions: The study indicates UC inserts achieve comparable posterior femoral rollback in deep flexion, supporting their alternative use, despite minor intraoperative flexion differences. However, paradoxical anterior translation in mid-flexion with UC inserts warrants further investigation into wear and clinical outcomes. [ABSTRACT FROM AUTHOR]

By deploying the methodology of Judith Butler's notion of performativity, this article intends to understand the possibility of the concept of queerness beyond the possibilities of gender studies and queer theory and to develop a concept transcending the limits of identity. It is undeniable that Foucault's concept of disciplinarity is one of the major precursors of the notion of performativity, which is a more focused tool for what Foucault broadly devised. Both thinkers explain how the subject is a construction by power. They explain how bodies are marked, assigned, and manipulated and expose the banality with which these operations take one for granted. It is through unearthing the disciplinary aspects of performativity in Butler and foreseeing the performative aspects of disciplinarity in Foucault that this article finds its methodological perspective. It is notable that disciplinarity and, as its extension, performativity ultimately exposes the underlying ontology of identity as a 'truth effect' rather than as an apriori truth. The paper critically analyses the artist's identity and the artistic discourse to unravel the queerness or an underlying plurality of aesthetic experience using performativity as a formative tool. [ABSTRACT FROM AUTHOR]

We demonstrate a one-sided cavity on an optical nanofiber (ONF) using a composite method. The one-sided composite cavity is created by mounting an asymmetric defect mode grating on an ONF. We design the one-sided composite cavity on an ONF to enhance channeling efficiency into one side of ONF while operating from under- to critical- and over-coupling regimes using numerical simulations. Experimentally, we demonstrate coupling characteristics of the one-sided composite cavity, showing good correspondence with simulation results. [ABSTRACT FROM AUTHOR]

Imaging probes which work at relatively low microwave frequencies in the ultrahigh frequency band (UHF) facilitate imaging through high loss dielectric materials and yield manageable imaging system complexity. However, acquiring images with resolutions on the order of few millimeters at frequencies within the UHF band requires super-resolution imaging methods and probes. In this paper, a compact near-field imaging probe working in the UHF band is proposed for high-resolution noninvasive imaging applications. The proposed probe is based on an electrically small loop loaded with a miniaturized spiral resonator. The probe is analyzed in this paper using numerical electromagnetic simulations and its equivalent circuit model is consequently developed. A prototype of the proposed probe operating at 426 MHz is fabricated and its spatial resolution as well as sensitivity are experimentally verified. A spatial resolution of around $\lambda $ /140 is demonstrated in simulations and verified experimentally. In order to highlight the utility of the probe for practical applications, images of many test samples including multilayer dielectric composite structures and corroded metallic substrate are acquired using the fabricated prototype. It will be shown that the images obtained using the proposed probe is comparable with those produced using an open-ended rectangular waveguide operating at 24 GHz. The salient features of the proposed probe include its high sensitivity and resolution while operating at relatively low frequency. [ABSTRACT FROM AUTHOR]

Molybdenum disulphide (MoS2) is widely explored in the area of electrochemical energy storage devices as an alternative to graphene. Here we introduce a 1T-MoS2 electrode with defect induced active edges for high performance supercapacitors. The metallic phase (1T) facilitates enhanced electrical conductivity and defect rich morphology that results in a high specific capacitance value. The structural characterisation confirms the formation of 1T phase and defect concentration in the material. Transmission electron microscopy imaging further confirms the presence of defects in high defect density MoS2 (HDD-MoS2) and low defect density MoS2 (LDD-MoS2). The electrochemical studies show that the prepared high defect density MoS2 electrode exhibits a maximum specific capacitance of 379 F g−1 and 68.9 F g−1 at 1 A g−1 current density in three and two electrode systems, respectively. The symmetric HDD-MoS2 supercapacitor exhibits an outstanding cell performance with an energy density of 21.3 W h kg−1, at a power density of 750 W kg−1 and a capacitance retention of 92% after 3000 cycles. These findings suggest that 1T MoS2 with high defect density can be a potential candidate for high performance supercapacitor electrode application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gel polymer electrolyte and sheet-like s-V 2 O 5 ·0.56H 2 O were prepared. • Gel polymer electrolyte with s-V 2 O 5 ·0.56H 2 O Zn2+ ion battery was demonstrated. • Gel polymer replaced aqueous electrolyte revealing excellent ZIBs performance. • Zn2+ insertion/deinsertion was confirmed by ex-situ Raman and XPS studies. Zinc-ion batteries (ZIBs) represent a promising technology since highly safe water or gel polymer electrolytes (GPE) are reliable and environmentally benign and have significant grid-level storage applications. However, Zn2+ strong charge interactions with the host cathode lattice result in poor reversibility, unwanted side reaction in the aqueous electrolyte, and sluggish Zn2+ diffusion in GPE, limitting its real-time application. Herein, we report the development of a large-scale water-molecule pre-intercalated sheet-like V 2 O 5 (s-V 2 O 5 ·0.56H 2 O) cathode and GPE to address the aforementioned issues. The transparent GPE prepared by mixing poly(vinylidene fluoride- co -hexafluoropropylene), 1-ethyl-3-methylimidazolium tetrafluoroborate, and zinc trifluoromethanesulfonate. The s-V 2 O 5 ·0.56H 2 O exhibited a higher diffusion coefficient (2.46 × 10−10 cm−2 s−1) than the commercial V 2 O 5 (2.18 × 10−11 cm−2 s−1) electrode. The Zn2+ intercalation/deintercalation and protonation/deprotonation mechanisms were investigated by ex-situ Raman and X-ray photoelectron spectroscopies in discharged (0.2 V) and charged (1.5 V) states. Overall, the s-V 2 O 5 ·0.56H 2 O cell in aqueous and GPE medium demonstrated a high capacity of 407 and 197 mAh/g (0.2 A/g), respectively. The aqueous and GPE mediated cell revealed high Coulombic efficiency (98 % and ∼ 100 % after 1000 cycles) and long-term cycling stability (for aqueous: 69 % and GPE: 74 % at 1000 cycles). The ex-situ surface study of the Zn anode revealed the flat zinc plating upon GPE usage rather than the aqueous electrolyte flake structure. This water-molecule pre-intercalated sheet-like V 2 O 5 cathode with GPE cell as potential Zn2+ ion battery power supplied to the liquid crystal display monitor. [ABSTRACT FROM AUTHOR]

Abstract: The effect of copper layer on the microstructural and electrical properties of copper (Cu)/zinc oxide (ZnO) thin film structure on glass substrate, prepared by radio frequency (RF) magnetron sputtering have been investigated. Cu/ZnO thin film structures possess good microstructural and electrical properties which are correlated with Cu thickness. The crystal structure, elemental analysis, surface topography and electrical properties of the films were systematically investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) with an energy dispersive X-ray spectroscopy (EDS) setup, atomic force microscopy (AFM) and four point probe analysis, respectively. The result showed that Cu/ZnO films exhibit high crystallinity with a very sharp intense XRD peak corresponding to lattice reflection plane (002) of a hexagonal wurtzite structure. Cu/ZnO film with higher copper thickness shows uniform grains which are densely packed and have distinct grain boundary. Cu/ZnO film with optimum copper thickness showed the lowest resistivity of 1.53×10−3 Ω-cm and sheet resistance of 5.06×102 Ω/sq. [Copyright &y& Elsevier]

[Display omitted] • Carbon-coated CoFe 2 O 4 MNPs achieve a high capacitance of 323 F/g. • Surface-modified CoFe 2 O 4 shows decreased magnetization due to non-magnetic carbon. • Carbon/CoFe 2 O 4 MNPs retain 84 % capacitance after 4000 cycles. • Core-shell-like morphology observed in carbon-coated CoFe 2 O 4 MNPs. • Study reveals potential of magnetic nanostructures in energy devices. The precise design and surface modification of electrode materials are crucial challenges for advancing the supercapacitor technology. In this study, we report a straightforward two-step process for the synthesis of a cobalt ferrite (CoFe 2 O 4)/carbon hetero nanostructure. The CoFe 2 O 4 nanoparticles were first synthesized using a simple chemical oxidation method, followed by carbon modification using glucose. The modified samples were calcined at 400 and 600 °C for 4 h in N 2 atmosphere to optimize the structural and electrochemical properties. The increase in the grain size of carbon modified cobalt ferrite magnetic nanoparticles (MNPs) was observed from 22 to 28 nm with post annealing temperature. The presence of carbon was confirmed by the FTIR spectroscopy, FESEM and TEM analyses. The carbon decoration on the cobalt ferrite partially showed a core–shell like morphology. The saturation magnetization of bare cobalt ferrite was observed to be 76 emu/g and the same was decreased by the surface modification with carbon. A high specific capacitance of 323 F/g was observed for the carbon-modified cobalt ferrite MNPs annealed at 600 °C. The electrochemical impedance spectroscopy (EIS) analysis demonstrated that the charge-transfer resistance (R ct) decreased significantly in the carbon-modified CoFe 2 O 4 MNPs, particularly for the sample annealed at 600 °C, with an R ct value of 17 Ω. The carbon layer effectively enhanced conductivity and reduced the electrode/electrolyte interface, led to the improved electrochemical performance, as reflected in the enhanced specific capacitance. An improved capacitance retention of 84 % was achieved in the case of carbon-modified cobalt ferrite MNPs based electrode even after 4000 cycles. The study suggested that the prepared carbon-modified cobalt ferrite MNPs stand in the limelight as a better candidate electrode material for the electrochemical applications. [ABSTRACT FROM AUTHOR]

LaMnO 3 nanoparticles with different levels of Ag doping are prepared and their impact on defect concentration and crystallite sizes are investigated. The crystallinity studies and phase identifications are done with XRD analysis. Williamson-Hall plots and size-strain plots are used to analyse the effect of doping on crystallinity and defect induced microstrain. With the help of Positron Annihilation spectroscopy, the identification of defects and mapping of the defect densities are carried out. Positron lifetime calculations and analysis on Doppler-broadened profile of the positron-electron annihilation radiation in undoped and various doped LaMnO 3 are carried out and compared with W-H plots and size-strain plots. [ABSTRACT FROM AUTHOR]

Time-delayed intensity–interferometry (TDII) measurements of the fluorescent emission from an ultracold ensemble of thermal 87Rb atoms in a steady-state magneto-optical trap are presented, which reveal the underlying coherent and incoherent dynamics of the atoms. Measurements carried out with a 5 ns time resolution yielded a second-order intensity correlation function with the theoretically predicted value of 2 at zero delay. In addition coherent Rabi oscillations were seen for up to five full periods—much longer than the spontaneous emission lifetime of the excited state of Rb. The oscillations were damped out by ∼150 ns, and thereafter an exponential decay observed, from which the mean velocity of atoms and thus, the temperature of the ensemble was estimated. The values so obtained compare well with those determined by standard techniques. It is seen that TDII permits a quantitative study of the coherent and incoherent processes, even in a large ensemble of independent atomic emitters in random thermal motion. This measurement of second-order correlation powerful technique can reveal hidden periodicities such as coherent Rabi oscillations that are not directly seen in the emission from a large collection of atoms. In addition it can also reveal information about the mean velocity of the thermal ensemble of emitters, even though the Doppler broadening of emission due to the motion of atoms is smaller than the natural linewidth and is not directly measureable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrode prepared by Au deposition, 4-ATP self-assembly, and p -ADPA grafting. • The SO 3 2− determined by nucleophilic addition on quinonimine polymer unit. • The SO 3 2− detection followed on E → C E → mechanism. • Ex-situ FTIR, XPS, and EIS studies confirmed SO 3 2− nucleophilic addition product. • p -ADPA-4-ATP-Au/GC revealed the high electron transfer rate 7.9 × 10−3 cm s−1. Realizing reagentless selective sodium sulfite (SO 3 2−) food-additive sensors for real-time applications is challenging. Regular SO 3 2− additive monitoring is necessary for providing harmless food to consumers. In this study, Au nanoparticles were prepared by electrodepositing Au3+ (+0.75 V vs. saturated calomel electrode) on a glassy carbon (GC) surface. An Au/GC surface self-assembled 4-aminothiophenol (4-ATP) (denoted as 4-ATP-Au/GC). The 4-ATP head group (-SH) was chemisorbed on S-Au/GC, while tail –NH 2 was functionalized using 4-aminodiphenylamine (ADPA) via a chemical/electrochemical approach. The as-prepared p -ADPA-4-ATP-Au/GC was thoroughly investigated stepwise by cyclic voltammetry traces and ex situ spectroscopy. We propose an E → C E → -mechanism-based SO 3 2− determination: p -ADPA-4-ATP-Au/GC was electrochemically oxidized to a quinonimine unit and chemically sulfonated by the nucleophilic addition reaction by SO 3 2−. This product was further electrochemically oxidized. The sulfonation of the polymer chains was confirmed using ex situ X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and electrochemical impedance spectroscopy. The p -ADPA-4-ATP-Au/GC composite electrode exhibited a wide linear range of SO 3 2− detection, from 5 to 160 μM. The sensitivity and detection limit were 0.0176 μA μM−1 and 1.5 μM, respectively. Finally, the p -ADPA-4-ATP-Au/GC was used in food samples containing SO 3 2−, which yielded a recovery in the range of 101.3–102.6%. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient electrochemical sensor for detecting FLD has been reported. • We have prepared FeVO/p-rGO NCs by a simple ultrasonic method. • The developed FeVO/p-rGO NCs/RRDE has a LOD of 138 nM for FLD detection. • The developed sensor shows good recovery results in real-time analysis of FLD. The improper discharge of organic toxicants, such as pesticides and antibiotics into water resources is a global problem that poses a serious threat to human health and the environment. In this work, an electrochemical sensor was developed for the selective detection of the antibiotic drug furaltadone (FLD) using iron vanadium oxide nanoparticles (Fe 0.11 V 2 O 5.16, FeVO NPs) wrapped porous reduced graphene oxide nanosheets (p-rGO NSs) nanocomposites (FeVO/p-rGO NCs) as an electrocatalyst. A simple hydrothermal method was used to synthesize FeVO NPs and p-rGO NSs. The structural and morphological properties of the nanocomposites were characterized by different characterization techniques such as XRD, Raman, XPS, FE-SEM, and HR-TEM analyses. Electrochemical studies were performed using EIS, CV, and amperometric (i-t) techniques. The FeVO/p-rGO NCs sensor shows two wider linear ranges from 0.5 to 84 µM and 94 to 1319 µM with a low detection limit of 138 nM (44.74 µg kg−1). The proposed sensor showed good recovery results for the determination of FLD in industrial wastewater and lake water samples. The results obtained with real samples prove that the developed sensor demonstrated its practical applicability for detecting environmentally hazardous pollutants and protecting our aquatic ecosystem. [ABSTRACT FROM AUTHOR]