Calix[4]arene emerges a wonderful host molecule in supramolecular chemistry for its non-covalent interaction with various guest ions via its unique cavity size, ability to functionalize with different reacting sites, and have good inclusion complex capability. In recent times, calix[n]arene based fluorescence sensors are promising probes for recognition of various guest molecules such as molecular ions, pesticides, explosives, biomolecules, small organic molecules and chiral molecules. This review focuses on brief history about supramolecular chemistry, calix[n]arene chemistry and its modification, fluorescence sensors and their mechanism, current trends in calix[n]arene-based fluorescence sensors linked with paper based analytical device hybrid with smart-phone devices. We have also discussed various mechanism involving in fluorescence sensor such as intramolecular charge transfer (ICT), fluorescence resonance energy transfer (FRET), photoinduced electron transfer (PET), chelation-enhanced fluorescence (CHEF), and chelation-enhanced quenching (CHEQ). In this review, we have highlighted fluorescence sensors for molecular ions, pesticides, and vitamin with their sensing mechanism, limit of detection (LOD), and linkage. Overall, this review provides an inclusive synopsis of the design principles, analytical applications, existing challenges, and future scenarios of calix[4]arene-based fluorescent sensors, highlighting their consequence as promising tools for environmental monitoring, food safety, and biomedical diagnostics.
Introduction: Ramsay Hunt syndrome (RHS) is an uncommon peripheral facial neuropathy caused by reactivation of latent varicella-zoster virus (VZV) within the geniculate ganglion, and it carries a worse prognosis for facial nerve recovery than idiopathic Bell's palsy1,2. Few reports detail the specific physical therapy decision-making - including the staged use of facial neuromuscular re-education and the deliberate avoidance of aggressive stimulation to prevent synkinesis - that accompanies pharmacological treatment of this condition. This case adds a structured, outcome-measure-driven account of physiotherapy management across the acute, paretic, and synkinesis-prevention phases of recovery. Main Symptoms and Important Clinical Findings: A 54-year-old male presented with a 3-day history of severe right-sided otalgia followed by acute right peripheral facial palsy, incomplete eye closure, and vesicular eruptions over the right pinna. Examination revealed House-Brackmann Grade V facial palsy with absent voluntary movement of the frontalis, orbicularis oculi, orbicularis oris, and zygomaticus major, accompanied by reduced taste sensation and diminished lacrimation on the affected side. Main Diagnoses, Therapeutic Interventions, and Outcomes: The clinical triad of otalgia, vesicular rash, and lower motor neuron facial palsy, supported by VZV-positive vesicle fluid PCR and MRI enhancement of the facial nerve, confirmed the diagnosis of Ramsay Hunt syndrome. Management combined oral antiviral therapy, corticosteroids, and ocular protection with a phased physiotherapy protocol progressing from gentle circulatory massage and eye protection in the acute flaccid phase to mirror-guided neuromuscular re-education and EMG biofeedback as paresis resolved. Conclusion: Early antiviral and corticosteroid therapy combined with a carefully staged, low-effort facial re-education program — rather than early aggressive stimulation — may support functional recovery while minimizing the risk of synkinesis in patients with Ramsay Hunt syndrome. Keywords: Ramsay Hunt syndrome; facial nerve palsy; varicella-zoster virus; facial neuromuscular re-education; EMG biofeedback
Common-path digital holographic microscopy (DHM) provides high temporal stability for high-contrast three-dimensional quantitative phase imaging. In particular, self-referencing common-path DHM, in which a portion of the object beam serves as the reference, is preferred because it enables compact setups with fewer optical elements. However, the effective field of view (FoV) is reduced, and the reference may retain residual object information. Spatial resolution is also limited by diffraction, and most proposed solutions compromise these advantages by increasing system complexity and cost. Here, we present a simplified, full-field, self-referencing DHM configuration based on a diffraction grating. A pinhole at the Fourier plane spatially filters the zero-order diffraction to generate a clean, sample-free reference beam, enabling use of the entire FoV, unlike conventional self-referencing geometries, where superposition of diffraction-order images restricts the usable area. To address spatial resolution, we demonstrate the feasibility of integrating the setup with microsphere-assisted microscopy (MAM), which has recently emerged as a simple yet effective approach for resolution enhancement. As a proof of concept, the system is validated on a standard diffraction grating, resolving features below the diffraction limit of the corresponding conventional configuration.
Advanced semiconductor materials are of significant interest for energy and optoelectronics applications due to their essential role in the development of next, generation devices. Literature shows that alloy engineering is a promising method to adjust the physical properties of materials, especially for creating self, powered photodetectors. In the present study, we explore the structural, optical, and electrical characteristics of In-doped SnSe (In x Sn1-x Se; x = 0, 0.25, 0.50) single crystals grown using the Direct Vapor Transfer (DVT) technique. Our major emphasis is on photodetection behavior. XRD and HRTEM results confirm the orthorhombic crystal structure, and Raman analysis shows doping-induced lattice distortion evidenced by a blue shift of phonon modes. Resistivity as a function of temperature displays highly anisotropic charge transport behavior that is characteristic of layered van der Waals semiconductors. UV-vis measurements suggest the presence of tunable bandgaps ideal for broadband photodetection. Furthermore, In doped SnSe photodetectors under the self-biased condition demonstrate significantly improved photoresponsivity and detectivity when illuminated by multiple wavelengths. The findings of this investigation supply a viable method to fabricate high, efficiency photodetectors that can contribute to the achievement of SDGs 7 and 9.
The complex permittivity spectra (epsilon*) of methanol-bromoethane binary mixtures over the full composition range (0.0-1.0 volume fraction) were investigated using time-domain reflectometry in the frequency range 0.01-25 GHz at 283.15-298.15 K. Ultrasonic velocity and refractive index were measured using a DMA 5000 M densimeter and an Abbe refractometer, respectively. Complex nonlinear least-squares fitting yielded dielectric parameters static dielectric constant (epsilon 0) and relaxation time (tau). Molecular interactions were analysed through Kirkwood correlation factors, Bruggeman factor and parameters derived from the Winkelmann-Quitzsch equation, including excess Helmholtz free energy and excess molar polarisation. Dipolar behaviour was resolved into long-range electrostatic interactions and short-range self- and cross-associations. Acoustic and refractometric parameters were evaluated, and excess properties were fitted using the Redlich-Kister polynomial. The results elucidate heteromolecular interactions in the studied system.
