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We theoretically investigate the ability to design optical filters from a single material and a single layer of randomly dispersed resonant dielectric particles, defining a random metasurface. Using a Bayesian and generalized Mie inverse-design approach, we design particle radii distributions that give rise to longpass, shortpass, bandpass, and bandstop spectral bands in the infrared. The optical response is shown to be directly related to electric and magnetic multipole scattering of the constituent particles and their near field coupling. We discuss the effect of the particle size distribution and particle–particle coupling interactions on filter design in random systems lacking long-range order.

5'10'. DARK HAIR. Gentle and easygoing. At the time of his death, in the '60s, they said he had schizophrenia, but the diagnosis today likely would be a developmental disability, [...]

BACKGROUND: Immersive, realistic, and low-risk training has long been ideal for skill-based disciplines such as surgery. Recent advances in virtual reality technology have led to development of surgical training software with the goal to provide experience without risk. The aim of this review is to summarize the current data for virtual reality-based orthopaedic surgery training to evaluate how beneficial the technology may become in educational circumstances. METHODS: A literature review was completed analyzing eight randomized controlled trials completed between 2019 to 2022 to evaluate the effect of virtual reality on orthopaedic surgery education for medical students and residents. Each trial included groups of learners that were trained on a specific procedure with standard methods (“control”) or virtual reality software (“VR group”). Subjects were then evaluated on completion of procedures with real-life models. Procedures included total hip arthroplasty (n=2), tibial intramedullary nail (n=2), slipped capital femoral epiphysis pinning (n=2), and unicompartmental knee arthroplasty (n=2). The primary metrics assessed were time to complete procedure and objective assessment scores. Secondarily survey results were evaluated regarding subjects’ perceived utility of virtual reality in orthopaedic surgery training. RESULTS: 168 subjects (medical students n=68, residents n=100) were included across the 8 different trials. All trials included at least one objective assessment and it was found that overall, the VR group performed 19.9% better than control group on average (19.875 ± 18.324, 95% CI). Seven of the trials reported time to complete procedure, in which it was found that overall VR group completed the procedures 12% faster than control group on average (12 ± 10.988, 95% CI). Subjective measures showed that over 70% of subjects found the VR learning to be at least “helpful” or “useful”. CONCLUSION: Early studies of the emerging field of virtual reality in surgical training are promising. When looking at objective measures and time to complete procedures, VR trained learners perform as well, if not better, than standard method learners. Inclusion of virtual reality-based practice in medical school curricula and residency training may lead to less surgical errors, increased knowledge of procedures, and more efficient learning in real-life scenarios. This potential impact extends beyond well-resourced institutions, as VR technology can provide a cost-effective and accessible alternative for surgical training in low-income and low-resource areas of the world, democratizing access to high-quality medical education. Continued research on translation into clinical practice is warranted, with the potential to bridge educational disparities and improve surgical outcomes on a global scale.

Progressive iron accumulation and renal impairment are prominent in both patients and mouse models of sickle cell disease (SCD). Endothelin A receptor (ETA) antagonism prevents this iron accumulation phenotype and reduces renal iron deposition in the proximal tubules of SCD mice. To better understand the mechanisms of iron metabolism in the kidney and the role of the [ET.sub.A] receptor in iron chelation and transport, we studied renal iron handling in a nonsickle cell iron overload model, heme oxygenase-1 ([Hmox-1.sup.-/-]) knockout mice. We found that [Hmox-1.sup.-/-] mice had elevated plasma endothelin-1 (ET-1), cortical ET-1 mRNA expression, and renal iron content compared with [Hmox-1.sup.+/+] controls. The [ET.sub.A] receptor antagonist, ambrisentan, attenuated renal iron deposition, without any changes to anemia status in Hmox-1mice. This was accompanied by reduced urinary iron excretion. Finally, ambrisentan had an important iron recycling effect by increasing the expression of the cellular iron exporter, ferroportin-1 (FPN-1), and circulating total iron levels in [Hmox-1.sup.-/-] mice. These findings suggest that the ET-1/[ET.sub.A] signaling pathway contributes to renal iron trafficking in a murine model of iron overload. Keywords: endothelin-1, iron homeostasis, ferroportin-1, sickle cell disease L'accumulation progressive de fer et l'insuffisance renale progressive se retrouvent de maniere proeminente chez les patients atteints d'anemie falciforme (AF) comme dans les modeles de la maladie chez la souris. L'antagonisme des recepteurs de l'endotheline A (ETA) permet de prevenir ce phenotype d'accumulation de fer et d'attenuer le depot de fer au niveau des tubules proximaux des reins de souris AF. Afin de mieux comprendre les modes d'action du metabolisme du fer dans les reins et le role des recepteurs [ET.sub.A] dans la chelation et le transport du fer, nous avons etudie la gestion du fer renal dans un modele de surcharge en fer sans AF : la souris << knock-out >> heme oxygenase 1 ([Hmox-1.sup.-/-]). Nous avons observe que la souris [Hmox-1.sup.-/-] presentait des taux plasmatiques d'endotheline 1 (ET-1), une expression corticale d'ET-1 en ARNm et des taux de fer dans les reins plus eleves que les temoins [Hmox-1.sup.+/+]. L'ambrisentane, un antagoniste des recepteurs ETA, permettait d'attenuer le depot de fer dans les reins sans aucune modification de l'etat anemique des souris [Hmox-1.sup.-/-], ce qui s'accompagnait d'une diminution de l'excretion urinaire du fer. Enfin, l'ambrisentane avait un important effet de recyclage du fer par l'entrainement d'un accroissement de l'expression de la ferroportine 1 (FPN-1), un exportateur de fer cellulaire, de meme que des taux de fer en circulation chez les souris [Hmox-1.sup.-/-]. Ces resultats laissent entendre que la voie de signalisation ET-1/ETA participerait au trafic du fer renal dans un modele de surcharge en fer chez la souris. Mots-cles : endotheline-1, homeostasie du fer, ferroportine 1, anemie falciforme, Introduction Iron homeostasis is fundamental for physiological processes in the body, and its imbalance has severe health consequences. Thus, iron metabolism is tightly regulated at the systemic and cellular levels. [...]

We have used the multiobject mode of the Near-Infrared Spectrograph (NIRSpec) on board the James Webb Space Telescope (JWST) to obtain low-resolution 1–5 μ m spectra of 22 brown dwarf candidates in the Orion Nebula Cluster, which were selected with archival images from the Hubble Space Telescope. One of the targets was previously classified as a Herbig–Haro (HH) object and exhibits strong emission in H i, H2, and the fundamental band of CO, further demonstrating that HH objects can have bright emission in that CO band. The remaining targets have late spectral types (M6.5 to early L) and are young based on gravity-sensitive features, as expected for low-mass members of the cluster. According to theoretical evolutionary models, these objects should have masses that range from the hydrogen burning limit to 0.003–0.007 M ⊙. Two of the NIRSpec targets were identified as proplyds in earlier analysis of Hubble images. They have spectral types of M6.5 and M7.5, making them two of the coolest and least massive known proplyds. Another brown dwarf shows absorption bands at 3–5 μ m from ices containing H2O, CO2, OCN−, and CO, indicating that it is either an edge-on class II system or a class I protostar. It is the coolest and least massive object that has detections of these ice features. In addition, it appears to be the first candidate for a protostellar brown dwarf that has spectroscopy confirming its late spectral type. [ABSTRACT FROM AUTHOR]

Objective: To gather preliminary evidence on short- and long-term care priorities for people with lower extremity amputations. Design: A three-round modified Delphi study using semi-structured interviews. Participants: A convenience sample of 20 adult participants who had undergone lower extremity amputations at a tertiary public hospital. Main Measure: Consensus on each care priority was defined a priori as an agreement of more than 50%. Semi-structured interviews were conducted to understand the rationales for endorsing the care priorities. Results: Consensus was reached on 24 short-term care priorities and 12 long-term care priorities in the biomedical, practical and psychological and spiritual domains. The rationales for endorsing each of the care priorities generated three themes: preparedness; mental health, psychological and spiritual well-being; and participating in life, with respect and dignity. Conclusions: Our results highlight the substantial need to improve patient access to education and planning support prior to undergoing limb amputation, and optimising post-amputation rehabilitation programmes, enabling people with amputations to participate in meaningful life roles that provide them with purpose, dignity, and self-respect. The knowledge of care priorities revealed in this study may promote effective patient-centred care and improve clinical outcomes. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is a common condition, and the number of cases is projected to increase 52% between 2012 and 2030. Care of breast cancer patients occurs along an interdisciplinary continuum involving family physicians, general surgeons, radiologists, pathologists, medical oncologists, radiation oncologists, and allied health workers. There are national benchmarks for wait times between each step from diagnosis to treatment. In this quality improvement project, we sought to measure these wait times at our hospital by comparing results for 2013 and 2023, identifying causes of delays, and proposing solutions to reduce wait times. Methods: We included all patients who were diagnosed with breast malignancies and referred to the general surgery service at Vernon Jubilee Hospital in 2013 and 2023. Results were analyzed using the two-tailed t test and Fisher exact test for continuous and categorical variables, respectively. A P value less than .05 was considered significant. Results: The number of patients increased from 69 in 2013 to 113 in 2023. Mean wait times from initial imaging referral to surgery increased from 67 to 114 days (P < .01) during this period. Mean wait times from imaging referral to pathology diagnosis increased from 36 to 71 days (P < .01), due primarily to an increase from 34 to 80 days for symptomatic patients who were referred by their family physician (P < .01); wait times for asymptomatic patients who were identified by the Screening Mammography Program increased from 40 to 58 days (P = .09). Mean wait times from biopsy to final biomarker report (ER/PR/HER2) increased from 25 days to 29 days (P = .25), from surgery to final pathology increased from 11 to 17 days (P < .01), from surgical consultation to surgery increased from 17 to 31 days (P < .01), from referral to medical oncology consultation increased from 14 to 30 days (P < .01), and from referral to radiation oncology consultation increased from 78 to 106 days (P = .025). Most wait times met benchmark wait times in 2013 but failed to meet them in 2023. Conclusions: Wait times increased at every stage of the care continuum for breast cancer patients between 2013 and 2023 at Vernon Jubilee Hospital. Implementing an interdisciplinary approach to care is necessary to remediate sources of delays at each step. Possible solutions include creating a fast-track pathway for symptomatic patients, performing biomarkers and pathology slide preparation locally, increasing operating room time, and tripling the number of oncologists in the region. [ABSTRACT FROM AUTHOR]

As Professors, we are challenged to reach ever-changing cohorts of college students as they flow through our classes and our lives. Technological advancements happen daily and we need to decide which, if any, to incorporate into our classrooms. Our students constantly check Facebook, Twitter, MySpace and other online social networks. Should we be posting course materials to these sites, or using them as communication vehicles? We asked 236 students in two states if they believe there is a use for these sites in the learning process. The answer was a definite NO. Students want to keep their social roles and their student roles separate.

We derive reduced models for extrusion problems where it is necessary to account for fluid compressibility.We consider the two-dimensional extensional flow of a compressible viscous fluid and discuss two specific applications: weakly compressible fluids and bubbly liquid--gas mixtures that behave as a single compressible fluid. The mathematical model we present consists of equations for conservation of mass, conservation of momentum and a closure relationship between the pressure and density. The most substantial differences between compressible extrusion problems is in the closure relationship. By integrating the conservation equations across the fluid cross-section and exploiting a slender aspect ratio, we derive reduced equations for conservation of mass and conservation of momentum in the direction of flow. The reduced system of equations relating cross-sectionally averaged quantities is closed by a relationship between the averaged pressure and density, which will differ substantially depending on the application. We demonstrate the utility of a reduced model for both the weakly compressible fluid and bubbly mixture applications; namely, in providing valuable quantitative insights without needing to solve a complicated free-boundary problem. [ABSTRACT FROM AUTHOR]

Color centers that emit light at telecommunication wavelengths are promising candidates for future quantum technologies. A pressing challenge for the broad use of these color centers is the typically low collection efficiency from bulk samples. Here, we demonstrate enhancements of the emission collection efficiency for Er 3 + incorporated into 4H-SiC surface nano-pillars fabricated using a scalable top-down approach. Optimal Er ion implantation and annealing strategies are investigated in detail. The substitutional fraction of Er atoms in the SiC lattice is closely correlated with the peak photoluminescence intensity. This intensity is further enhanced via spatial wave-guiding once the surface is patterned with nano-pillars. These results have broad applicability for use with other color centers in SiC and also demonstrate a step toward a scalable protocol for fabricating photonic quantum devices with enhanced emission characteristics. [ABSTRACT FROM AUTHOR]