Seasonal Variation in Fish Assemblages Within the Estuarine Portions of the Myakka and Peace Rivers, Southwest Florida

Juvenile and small adult fish were sampled monthly from 1996 to 2002 in the estuarine portions of the Myakka and Peace rivers, at the northern end of Charlotte Harbor (a relatively pristine estuarine system in southwest Florida). We provide a detailed description of the fish faunas in these areas, including seasonal assemblage structure. Seasonal cycles in assemblage structure were evident. Nearshore (to ~5 m) fish assemblages sampled by seine were separated into three main seasonal groups by cluster analysis (January-April, May-September, September-January). The ichthyofauna collected from deeper (≥1.8 m) areas by otter trawl formed two seasonal groups (June-October and November-March). Small schooling taxa such as Anchoa mitchilli, Menidia spp. and Eucinostomus spp. dominated seine catches, and variations in their abundances contributed greatly to dissimilarities between seasons, as did seasonal recruitment of young-of-the-year (YOY) estuary-dependent species such as Mugil cephalus, Lagodon rhomboides, Leiostomus xanthurus, and Bairdiella chrysoura. Estuarine residents (e.g., A. mitchilli and Trinectes maculatus) and YOY estuary-dependent species (e.g., Cynoscion arenarius and Menticirrhus americanus) were important in defining seasonal dissimilarities in fish assemblages from the trawled areas. Correlations between biotic patterns and environmental factors (water temperature, salinity, dissolved oxygen, precipitation, and river discharge) were relatively low, perhaps reflecting the euryhaline nature of the fish present and their intrinsic spawning periods. The present study provides a detailed description of temporal ichthyofaunal patterns in the estuarine portions of two tidal rivers in southwest Florida and provides a baseline with which future fish populations in this area can be compared

Spectral and spatial shaping of Smith Purcell Radiation

The Smith Purcell effect, observed when an electron beam passes in the vicinity of a periodic structure, is a promising platform for the generation of electromagnetic radiation in previously-unreachable spectral ranges. However, most of the studies of this radiation were performed on simple periodic gratings, whose radiation spectrum exhibits a single peak and its higher harmonics predicted by a well-established dispersion relation. Here, we propose a method to shape the spatial and spectral far-field distribution of the radiation using complex periodic and aperiodic gratings. We show, theoretically and experimentally, that engineering multiple peak spectra with controlled widths located at desired wavelengths is achievable using Smith-Purcell radiation. Our method opens the way to free-electron driven sources with tailored angular and spectral response, and gives rise to focusing functionality for spectral ranges where lenses are unavailable or inefficient

Smith-Purcell Radiation from Low-Energy Electrons

Recent advances in the fabrication of nanostructures and nanoscale features in metasurfaces offer a new prospect for generating visible, light emission from low energy electrons. In this paper, we present the experimental observation of visible light emission from low-energy free electrons interacting with nanoscale periodic surfaces through the Smith-Purcell (SP) effect. SP radiation is emitted when electrons pass in close proximity over a periodic structure, inducing collective charge motion or dipole excitations near the surface, thereby giving rise to electromagnetic radiation. We demonstrate a controlled emission of SP light from nanoscale gold gratings with periodicity as small as 50 nm, enabling the observation of visible SP radiation by low energy electrons (1.5 to 6 keV), an order of magnitude lower than previously reported. We study the emission wavelength and intensity dependence on the grating pitch and electron energy, showing agreement between experiment and theory. Further reduction of structure periodicity should enable the production of SP-based devices that operate with even slower electrons that allow an even smaller footprint and facilitate the investigation of quantum effects for light generation in nanoscale devices. A tunable light source integrated in an electron microscope would enable the development of novel electron-optical correlated spectroscopic techniques, with additional applications ranging from biological imaging to solid-state lighting.Comment: 16 pages, 4 figure

Does case management improve diabetes outcomes?

Patients with type 2 diabetes benefit from case management, as evidenced by decreased glycated hemoglobin (HbA1c). The improvement in HbA1c appeared larger when case managers could make changes in medications independently and multidisciplinary teams were used (strength of recommendation [SOR]: C, 2 meta-analyses of randomized controlled trials [RCTs] with consistent disease-oriented findings). Patients with type 1 diabetes who have case management and "intense control" experience fewer cardiovascular events and decreased retinopathy and clinical neuropathy (SOR: B, 1 large, good-quality RCT)

Monochromatic X-ray source based on scattering from a magnetic nanoundulator

We present a novel design for an ultra-compact, passive light source capable of generating ultraviolet and X-ray radiation, based on the interaction of free electrons with the magnetic near-field of a ferromagnet. Our design is motivated by recent advances in the fabrication of nanostructures, which allow the confinement of large magnetic fields at the surface of ferromagnetic nanogratings. Using ab initio simulations and a complementary analytical theory, we show that highly directional, tunable, monochromatic radiation at high frequencies could be produced from relatively low-energy electrons within a tabletop design. The output frequency is tunable in the extreme ultraviolet to hard X-ray range via electron kinetic energies from 1 keV-5 MeV and nanograting periods from 1 {\mu}m-5 nm. Our design reduces the scale, cost, and complexity of current free-electron-driven light schemes, bypassing the need for lengthy acceleration stages in conventional synchrotrons and free-electron lasers and driving lasers in other compact designs. Our design could help realize the next generation of tabletop or on-chip X-ray sources.Comment: 8 pages, 4 figure

Transcending shift-invariance in the paraxial regime via end-to-end inverse design of freeform nanophotonics

Traditional optical elements and conventional metasurfaces obey shift-invariance in the paraxial regime. For imaging systems obeying paraxial shift-invariance, a small shift in input angle causes a corresponding shift in the sensor image. Shift-invariance has deep implications for the design and functionality of optical devices, such as the necessity of free space between components (as in compound objectives made of several curved surfaces). We present a method for nanophotonic inverse design of compact imaging systems whose resolution is not constrained by paraxial shift-invariance. Our method is end-to-end, in that it integrates density-based full-Maxwell topology optimization with a fully iterative elastic-net reconstruction algorithm. By the design of nanophotonic structures that scatter light in a non-shift-invariant manner, our optimized nanophotonic imaging system overcomes the limitations of paraxial shift-invariance, achieving accurate, noise-robust image reconstruction beyond shift-invariant resolution

End-to-End Optimization of Metasurfaces for Imaging with Compressed Sensing

We present a framework for the end-to-end optimization of metasurface imaging systems that reconstruct targets using compressed sensing, a technique for solving underdetermined imaging problems when the target object exhibits sparsity (i.e. the object can be described by a small number of non-zero values, but the positions of these values are unknown). We nest an iterative, unapproximated compressed sensing reconstruction algorithm into our end-to-end optimization pipeline, resulting in an interpretable, data-efficient method for maximally leveraging metaoptics to exploit object sparsity. We apply our framework to super-resolution imaging and high-resolution depth imaging with a phase-change material: in both situations, our end-to-end framework computationally discovers optimal metasurface structures for compressed sensing recovery, automatically balancing a number of complicated design considerations. The optimized metasurface imaging systems are robust to noise, significantly improving over random scattering surfaces and approaching the ideal compressed sensing performance of a Gaussian matrix, showing how a physical metasurface system can demonstrably approach the mathematical limits of compressed sensing

Early bone healing around implant surfaces treated with variations in the resorbable blasting media method. A study in rabbits

Objective: this study aimed to histomorphologically and histomorphometrically evaluate the in vivo response to three variations in the resorbable blasting media (RBM) surface processing in a rabbit femur model. Study Design: screw root form implants with 3.75 mm in diameter by 8 mm in length presenting four surfaces (n=8 each): alumina-blasted/acid-etched (AB/AE), bioresorbable ceramic blasted (TCP), TCP + acid etching, and AB/AE + TCP were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The implants were placed at the distal femur of 8 New Zeland rabbits, remaining for 2 weeks in vivo. After sacrifice, the implants were nondecalcified processed to 30 micro m thickness slides for histomorphology and bone-to-implant contact (BIC) determination. Statistical analysis was performed by one-way ANOVA at 95% level of significance considering implant surface as the independent variable and BIC as the dependent variable. Results: SEM and AFM showed that all surfaces presented rough textures and that calciu-hosohate particles were observed at the TCP group surface. Histologic evaluation showed intimate interaction between newly formed woven bone and all implant surfaces, demonstrating that all surfaces were biocompatible and osseoconductive. Significant differences in BIC were observed between the AB/AE and the AB/AE + TCP, and intermediate values observed for the TCP and TCP + Acid surfaces. Conclusion: irrespective of RBM processing variation, all surfaces were osseoconductive and biocaompatible. The differences in BIC between groups warrant further bone-implant interface biomechanical characterization

Desenvolvimento de um sistema de alerta para prevenção de quedas em pacientes hospitalizados

The present study describes the analysis of an online patient assessment system developed to prevent inpatients falls. A chart review was performed in order to identify risk factors present in the Nursing Assessment tool. The identified variables were Functional status including walking, transferring and toilet, sex and patients self-care ability. Authors developed a system using these variables, that is available since February 1997. In a second phase of this study, authors aim to evaluate the effectiveness of this computerized intervention.Este estudio describe el análisis de un sistema de computación en enfermería para desarrollar un sistema de alerta para prevenir caídas de los hospitalizados. Una revisión de las historias clínicas fue realizada para identificar los factores de riesgo presentes en el referido instrumento de evaluación. Las variables identificadas fueron: estado funcional del paciente incluyendo andar, desplazamiento, limpieza, sexo y habilidad para realizar el autocuidado. Usando estas variables un sistema de alerta fue desarrollado e incorporado en el sistema desde febrero de 1997. En una segunda fase de este estudio nos preponemos evaluar la eficacia de esta intervención automatizada en la calidad del cuidado de enfermería..Este estudo descreve a análise de um Sistema computadorizado de avaliação do paciente no desenvolvimento de um sistema de alerta para prevenir quedas de pacientes hospitalizados. Foi realizada a revisão de prontuários para identificar os fatores de risco presentes no referido instrumento de avaliação. As variáveis identificadas foram: estado funcional do paciente incluindo andar, transferir-se e toilete, sexo e habilidade de realizar auto-cuidado. Usando tais variáveis, foi desenvolvido um sistema de alerta que encontra-se disponibilizado desde Fevereiro de 1997. Em uma segunda etapa, pretende-se estudar o impacto deste sistema na qualidade do atendimento de enfermagem