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To present a transparent, physics-based, and generalisable calculation framework to predict the optimal rotational adjustment of toric supplementary intraocular lenses (SIOLs), comprising toric phakic intraocular lenses implanted in the phakic eye and toric AddOn (secondary sulcus-fixated) lenses implanted in the pseudophakic eye, quantifying the expected refractive benefit across four corneal models. A paraxial vergence-based calculation framework was implemented to predict the optimal toric axis of a misaligned SIOL. Required inputs were the measured manifest refraction at spectacle plane, corneal power (using either thin- or thick-cornea models), labelled equivalent and toric power of the SIOL, measured SIOL axis, and axial SIOL position. The effective lens position was estimated by combining the measured back-vertex position with an offset between the back-vertex plane and the image-sided principal plane, derived from legacy phakic lens design data or custom template SIOL models. Forward and backward spherocylindrical vergence transformations were embedded in a nonlinear sequential quadratic programming optimisation to identify the SIOL axis that minimised residual refractive cylinder. The method was demonstrated in four representative clinical scenarios, including phakic, pseudophakic , keratoplasty, and prior laser vision correction eyes. In all examples, the model predicted a specific rotational adjustment of the SIOL (16-18°) that substantially reduced refractive cylinder. Absolute reductions ranged from 1.7 to 2.4 D, corresponding to relative cylinder reductions of 67-94%. The framework successfully accommodated different corneal models and lens types, and provided predicted postoperative refraction and quantitative performance metrics. This framework enables individualised planning of toric SIOL realignment across diverse corneal models and lens geometries. Explicitly defining optical assumptions and vergence transformations allows reproducible prediction of both optimal rotation and expected refractive benefit using routine clinical inputs. Prospective clinical validation is warranted.

Phacoemulsification followed by intraocular lens (IOL) implantation is currently the only effective treatment for cataracts. However, conventional IOLs exhibit limited biological adaptability and fixed or discontinuous focal properties, preventing restoration of the natural lens's continuous accommodation and often causing postoperative visual disturbances and complications. Herein, we report an injectable multifunctional hydrogel-based biomimic lens that simultaneously reconstructs optical-mechanical properties and dynamically modulates the postoperative lenticular microenvironment. Through multilayered dynamic crosslinking and micro-capsulorhexis-assisted in situ gelation within the capsular bag, the hydrogel forms a biomimic lens with continuous refractive characteristics. Meanwhile, its drug-loading capability enables the incorporation of multifunctional components for early postoperative antibacterial, anti-inflammatory, and antifibrotic effects. In addition, after inflammation subsides, the loaded photocatalytic elements induce the orderly clearance of residual lens epithelial cells, enabling comprehensive restoration of microenvironmental homeostasis within the capsular bag. In a rabbit model, this hydrogel lens demonstrates effective refractive reconstruction and sustained suppression of postoperative complications, highlighting its potential as a next-generation intraocular lens.

To compare the effects of blue light-filtering and non-blue light-filtering senofilcon A daily disposable contact lenses on color discrimination and contrast sensitivity in healthy young adults with myopia. This comparative study included 68 eyes of 34 myopic adults with best-corrected visual acuity of 0.0 logMAR. All participants were evaluated while wearing blue light-filtering and non-blue light-filtering senofilcon A daily disposable contact lenses. Color discrimination was assessed binocularly using the Farnsworth-Munsell 100 Hue test, with blue-yellow axis local error score (LES), red-green axis LES, and total error score (TES) recorded. Contrast sensitivity was evaluated monocularly using the Spaeth-Richman Contrast Sensitivity (SPARCS) test, and central, peripheral, and total SPARCS scores were compared between the two lens types. No statistically significant differences were observed between blue light-filtering and non-blue light-filtering contact lenses in blue-yellow axis LES (p = 0.130), red-green axis LES (p = 0.275), or TES (p = 0.090). Contrast sensitivity scores were significantly higher with blue light-filtering lenses than with non-blue light-filtering lenses in the central area (p = 0.009), superotemporal area (p = 0.024), inferotemporal area (p = 0.013), and in the total SPARCS score (p = 0.016). No significant differences were found in the superonasal or inferonasal areas. Blue light-filtering senofilcon A daily disposable contact lenses were associated with higher contrast sensitivity in central and selected peripheral visual field regions, without a measurable effect on color discrimination.

The purpose of this study was to model the effects of variation in the refractive index of the crystalline lens on theoretical biometric measurements. Measurement errors of the axial length of the eye (AL) and lens thickness (LT) were modelled while the lens refractive index and related ocular segment sizes were varied from a 30-year-old model eye. Two approaches of optical path-length (OPL) conversion, the weighted mean ocular refractive index (WMORI) and the segmented refractive index (SRI), were specifically examined. In the WMORI approach, when lens refractive index, LT and vitreous chamber depth (VCD) were varied together, AL measurement was either underestimated by 0.209 mm or overestimated by 0.390 mm. The VCD was a major influencing factor. In the SRI approach, the AL measurement error was reduced to 0.077 mm. The same amount of LT measurement error was also found as in the AL. The SRI approach provides an improvement over the WMORI in AL measurement because the influence of the VCD was eliminated. Use of a model eye parameter for OPL conversion always causes biometric measurement errors in individual eyes due to the variations in lens refractive index. The newly developed in vivo measurement of lens refractive index needs to be applied in optical biometry to improve AL and LT measurements for individual eyes in the areas of myopia research and cataract surgery.

The clinical management and visual rehabilitation of a 24-year-old female with bilateral keratoconus (OD > OS) successfully fitted with scleral lenses is presented. A comprehensive ophthalmic evaluation was performed, including keratometry, corneal topography using Pentacam imaging, and objective and subjective refraction. Objective refraction revealed +3.00 -5.00 × 105 in OD and +1.50 -3.00 × 080 in OS. The final spectacle prescription was +2.00 -4.50 × 105 in OD, achieving a visual acuity of 6/9- (20/30-), and +0.75 -3.00 × 080 in OS, achieving 6/6- (20/20-). Diagnostic scleral lenses were selected based on sagittal depth, guided by Kmax values. Baseline unaided visual acuity was 6/24 (20/80) in the right eye (OD) and 6/18 (20/60) in the left eye (OS), with near vision of N6 in both eyes (OU), since the patient had no current spectacles. With scleral lenses, best-corrected visual acuity improved to 6/6 (20/20) in both eyes (OU). Topographic analysis revealed advanced ectatic changes in OD (Kmax: 70.80 D; enhanced ectasia score: 17.99 D). The lenses demonstrated appropriate vault, limbal clearance, and uniform scleral alignment, ensuring stable centration, comfort, and protection of the ocular surface. Scleral lenses provided effective visual rehabilitation in advanced keratoconus, restoring 6/6 (20/20) vision bilaterally while preserving corneal health. This case highlights the clinical value of scleral lenses as a reliable approach for managing irregular corneas and progressive ectasia.

Many new optical treatments have been developed recently to slow the progression of myopia. Most of these are based on theories of how myopia develops, such as poor accommodation, the type of peripheral refraction and image contrast (contrast modulation). Optically related treatments include spectacle lenses, contact lenses, orthokeratology, light therapies, more outdoor time, better interior lighting, indoor illumination, pharmacological intervention (through pupil and accommodation effects) and combination therapies. Current myopia-control spectacle lenses are described, including progressive addition, multisegment, annular cylinder, diffusion optics technology and concentric bifocals. Background is provided and a critical eye is passed over some of the designs. Short-term (12-month) efficacies for both axial length and myopia reduction in myopia-control spectacle wear, relative to single-vision lenses, are about 50%, as compared to 50%, 60% and 80% for contact lenses, orthokeratology and red-light therapy, respectively. Spectacle lens treatments for myopia control are safe, valuable tools in clinical practice. Further laboratory and clinical studies should help to clarify the nature of the mechanisms of action and improve efficacy.

We show that oscillating (real-scalar) boson stars generically host an oscillating radial caustic. Sources near this caustic cross it every half period, thereby producing periodic caustic-crossing lensing. The resulting observables are phase locked to the lens oscillation: image-pair creation or annihilation, changing image morphology, achromatic photometric spikes, and astrometric motion. This signal provides a distinctive target for time-domain astronomy, and its detection would reveal an intrinsically time-dependent compact dark-sector object. Event-number estimates indicate a measurable discovery space with current astrometric and high-cadence photometric surveys, while null searches would constrain the abundance of such objects as dark matter. The predictions rely only on the dynamics of real-scalar condensates and extend naturally to self-interacting real scalars, including axionlike particles, and to ultralight vector bosons.

To evaluate the accuracy of ray tracing optimization (RTO) for predicting postoperative refractive error in keratoconic cataract eyes. University Eye Clinic, Maastricht, the Netherlands. Case series. Evaluation of technology. Twenty-two keratoconic eyes who underwent cataract surgery were included in the study. Anterior and posterior corneal Zernike coefficients, axial distances, and intraocular lens (IOL) geometry were exported to custom-developed RTO algorithms to build patient-specific eye models. Optical quality was quantified with the Visual Strehl ratio (VSOTF). The defocus and astigmatism maximizing VSOTF were taken as the optimal target refraction and compared with postoperative subjective refraction using power vectors (SEQ, J0, J45). Agreement was assessed with Bland-Altman analysis, and prediction accuracy was summarized as the percentage within ±0.5D and ±1.0D. Bland-Altman analysis showed good agreement between RTO-predicted and postoperative subjective refraction, particularly for SEQ (spherical equivalent) and J0 (with/against-the-rule astigmatism). The percentage of eyes within ±0.5D of prediction error was 68.2% for SEQ and J0 and 59.1% for J45; within ±1.0D it was 86.3% (SEQ), 81.8% (J0), and 77.3% (J45). Cataract surgery in keratoconic eyes did not induce significant variations in the corneal Zernike coefficients. RTO accuracy was highest when vertical coma (Z3-1) predominated as the main higher-order aberration. Aberration-guided RTO provides accurate postoperative refractive predictions in keratoconic cataract eyes. Accuracy is particularly strong in eyes dominated by vertical coma, supporting inclusion of measured higher-order aberrations in IOL power selection.

Secondary glaucoma following combined corneal transplantation and artificial iris-intraocular lens (IOL) complex implantation represents a significant therapeutic challenge. Reports of surgical management in such complex eyes remain limited. We report a case of successful PreserFlo MicroShunt implantation for the management of secondary glaucoma following combined Descemet stripping automated endothelial keratoplasty (DSAEK) and Reper artificial iris-IOL complex implantation. A 54-year-old woman with a history of right eye corneal perforation resulting in aphakia underwent combined DSAEK and Reper artificial iris-IOL complex implantation (Reper-NN LTD, Nizhny Novgorod, Russia). Six months after surgery, she developed secondary glaucoma with intraocular pressure (IOP) elevation to 30 mm Hg despite maximal tolerated medical therapy, accompanied by optic disc cupping, retinal nerve fiber layer thinning, and corresponding visual field defects. PreserFlo MicroShunt implantation was performed. Postoperatively, IOP decreased to 6 mm Hg with a well-functioning filtering bleb, and the corneal graft remained clear throughout the 3-month follow-up. To our knowledge, this is the first report describing PreserFlo MicroShunt implantation for secondary glaucoma following combined Reper artificial iris-IOL implantation and endothelial keratoplasty. This case highlights the potential role of PreserFlo as a surgical option for IOP control in highly complex anterior segment eyes.

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This study adopts the ethnography of musical performance as its methodological framework. Taking the Macao Guangdong Music Friendship Association as its primary field site, it employs a three-tiered "body-event-context" model to examine the living practices of a traditional music society in an urban setting. Through participant observation of rehearsals, teaching sessions, community festivals, and international performances, the research focuses on a micro-ethnographic thick description of the musicians' embodied practices, including playing postures, aural habits, and non-verbal interactions. The findings reveal that musical style is shaped through "embodied practice" and immersion in the local soundscape, giving rise to a distinctive "Macao taste" (Macao wei). The music society performs strategic cultural identity work across different social arenas through repertoire selection and embodied narratives. Furthermore, the stratified repertoire and original works such as Shengshi Haojiang (Prosperous Macao) constitute a living sound archive that documents and participates in local cultural-historical narratives and identity construction.

The experience of grief within neurosurgery extends across a diverse range of individuals, including patients, but also caregivers, neurosurgeons, trainees, advanced practice providers, and the nursing staff who care for neurosurgical patients. This congregation of individuals constitutes the sacred thread woven in the circle of neurosurgery. This interconnected circle is united by a string of life-changing experiences, most of which are profoundly rewarding. However, some experiences leave a deep, regretful mark on the "self," even when the highest standards are upheld in the operating room. In this article, authors from different expertise combine to discuss the factors that encompass the experience of grief among those who face the terminal phases of their lives, their loved ones, and those who incurred grief from the act of doer-ship (neurosurgeons and providers). The authors discuss the different dynamics of grief at play between these cohorts, which may be insightful for those caring for them, and delve into psychological and spiritual reflections on their potential roles in coping mechanisms. They introduce the concept of ikigai in the context of grief, particularly in conjunction with evidence-based breathwork and meditative practices.

Preceptorship is a cornerstone of clinical teaching in undergraduate nursing programs in several countries, including Saudi Arabia. However, the common challenges faced by both preceptors and preceptees have not been explored. To explore the preceptors' and preceptees' perceptions toward barriers faced during preceptorship program. A qualitative descriptive design using Braun and Clarke's six-step thematic analysis was adopted, and online semistructured interviews were conducted for each participant from March to June 2022. A purposive sample of 13 participants (eight preceptors and five preceptees) was recruited from hospitals in different regions of Saudi Arabia. To ensure scientific rigor, the study's credibility, confirmability, and transferability were determined. Two major themes emerged: (1) challenges of the preceptorship program (i.e., language barrier, lack of readiness to practice, lack of time, and lack of role preparation and direction and (2) strategies for improving preceptorship programs (i.e., having an organized preceptorship program and having organizational support). Preceptorship plays a vital role in helping nursing students develop clinical knowledge, confidence, and practical skills during their transition into professional practice. This study identified key barriers affecting effective preceptorship, including language challenges, limited readiness for practice, insufficient time, and unclear role preparation for both preceptors and preceptees. Strengthening preceptorship programs through structured organization, adequate staffing, proper preceptor support, and standardized training strategies can enhance clinical learning experiences and improve educational outcomes. The Consolidated Criteria for Reporting Qualitative Research checklist was followed.

Limbal, conjunctival or oral mucosal (OM) epithelial explant cultures are used to treat limbal epithelial stem cell deficiency (LSCD), however, their characteristics remain elusive. Explant cultures established on silicon hydrogel contact lenses and source tissue samples were examined by immunofluorescence microscopy for limbal epithelial progenitor, corneal differentiation, and putative limbal niche markers. Quantitative analysis was done using confocal images of whole slides. In all source tissue samples, many p63+ and some vimentin + basal epithelial as well as CD90+ stromal cells were seen. All epithelia expressed CXCR4. While SDF-1 was mostly in the epithelium and only weakly in the stroma of the limbus and conjunctiva, it was restricted to the stroma in OM. In all explant cultures, vimentin+/p63&#x3b1;+ small cells were abundant. For limbal explants, their ratio was highest at the source (68%) and decreased significantly with distance indicating highest regenerative and differentiation potential. OM showed the lowest ratio (38%) and no change by distance, while conjunctival explants were in the interim range. The density of both corneal-type CK3+ and less differentiated CK19+ epithelial cells increased with distance from the source for limbal and conjunctival samples (R2:0.3-0.44, p &#x2264; 0.05) but did not change for OM (R2 < 0.02, p > 0.47). In addition to the dominance of source-specific cytokeratin patterns, all CKs of mature stratified epithelium could be detected, while CK14 and CK15 evidenced the occurrence of less mature epithelial cells. Spatial maturation gradients were only characteristic of limbal sources. Some CD90+ putative niche cells, surrounded by CK15+ and nestin + cells formed distinct clusters in all samples. SDF-1 and CXCR4 were present in all cultures, and their distribution patterns showed similarities with the tissue of origin. Despite similarities, including putative niche-associated cell clusters, explant cultures on silicon hydrogel surfaces from all three epithelia maintain characteristics of their original source. Their SDF-1 and CXCR4 content indicates the ability to establish contact with the host limbal niche that may be a prerequisite for long-term survival and site-specific differentiation after transplantation. Limbal explants show the highest proliferative and differentiation potential, while the generation of corneal epithelial-like cells is increasingly less efficient from conjunctival and OM sources.

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Successful and responsible innovation in neurotechnology requires clear ethical priorities and a deep understanding of individual and societal needs as well as public concerns. Recent cases of consumer exploitation, misleading claims, and inadequate patient aftercare reveal critical gaps in current practices and underscore the urgent need for more ethical, transparent, and user-centered engagement in this rapidly developing field. This study focuses on four complementary domains: (1) neuroethics and embodiment; (2) the cultural embedding of neurotechnologies; (3) art and culture in relation to neurotechnology; and (4) human enhancement, technovisions, and sociotechnical imaginaries. Across these domains, the manuscript explores user and societal perceptions, highlighting often overlooked asymmetries in communication between scientists and entrepreneurs and those who ultimately receive research outcomes in the form of products. Drawing on the authors' multidisciplinary expertise and a synthesis of the relevant literature, the manuscript outlines a possible foundation for developing more balanced, inclusive and symmetric communication formats that empower stakeholders regardless of status or expertise. Integrating insights from neurotechnology with applied ethics, the humanities, social sciences, technology assessment and the arts, this work seeks to contribute to a broader understanding of the societal and individual impacts of emerging neurotechnologies and to support the protection and empowerment of users by prioritizing their needs.

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