The segmentation of blood vessels in retinal images is crucial to the diagnosis of many diseases. We propose a deep learning method for vessel segmentation based on an encoder-decoder network combined with squeeze-and-excitation connection and atrous spatial pyramid pooling. In our implementation, the atrous spatial pyramid pooling allows the network to capture features at multiple scales, and the high-level semantic information is combined with low-level features through the encoder-decoder architecture to generate segmentations. Meanwhile, the squeeze-and-excitation connections in the proposed network can adaptively recalibrate features according to the relationship between different channels of features. The proposed network can achieve precise segmentation of retinal vessels without hand-crafted features or specific post-processing.  https://www.selleckchem.com/products/zasocitinib.html  The performance of our model is evaluated in terms of visual effects and quantitative evaluation metrics on two publicly available datasets of retinal images, the Digital Retinal Images for Vessel Extraction and Structured Analysis of the Retina datasets, with comparison to 12 representative methods. Furthermore, the proposed network is applied to vessel segmentation on local retinal images, which demonstrates promising application prospect in medical practices.We propose a full-band model to quantitatively calculate terrestrial atmospheric scattering in stray light testing based on the Monte Carlo algorithm. Measurements are conducted using two classifications of air cleanliness at off-axis angles from 35° to 90°. Corresponding simulations of Mie scattering and Rayleigh scattering are used for a comparison with the measured values. The relative root mean square deviation of the simulation from the measurement result is 3.72% and 24.1% for Mie scattering and Rayleigh scattering, respectively. This exhibits excellent agreement between the measured and predicted values for a 26° full-angle baffle when illuminated by a 550 mm diameter collimated beam.In this work, we introduce a mixed complex and phase only constraint to the Gerchberg-Saxton (G-S) algorithm, leading to improvements in the generation of holograms from multiplane light field distributions. To achieve this, we determine the optimal weight factor for the complex and phase only part of a light field in every plane to achieve the best accuracy. We also demonstrate how this approach can be used to generate encrypted holograms that can only be reconstructed by illumination with a determined phase profile. In this way, we enable the possibility for secure, high-quality multiplane projection and display. We show numerical results for the generation of standard and encrypted seven-plane holograms, as well as the comparison with the conventional G-S algorithm.Dielectric metasurfaces, which are capable of manipulating incident light, have been a novel branch of flat optics. This modulation ability is realized by nanostructures with space-variant geometrical parameters such as height and diameter. Therefore, accurate profile measurement of metasurfaces is of great importance. White-light scanning interferometry is widely used for profile measurement. The step height is retrieved by locating the envelope's peak. However, spurious fringes attached to the desired fringes were observed at the measured area near the edge of nanostructures. Their amplitude distributions vary with the density of nanostructures as well as distance to the edge. Further, anomalous coherence signals with two fringe envelopes are produced, which result in inaccurate measurement results. We attributed this phenomenon to the complex light modulation by the nanostructures. When referring to the anomalous coherence signals for the top of the nanostructures, one envelope is produced by the top, and the other is produced by the bottom; however, it is difficult to distinguish these two, which is the same case for the bottom of the nanostructures. To automatically solve these obstacles, a signal processing method, which integrates the image segmentation technology to identify and divide the anomalous coherence signals, along with a Morlet wavelet transform to extract the fringe envelope, suitable for any measured area of the dielectric metasurface, is proposed. One metasurface belt consisting of seven kinds of nanopillars with varying arrayed densities that produce different coherence signals is measured. The diameter distribution ranges from 500 to 1250 nm with a constant height of 1850 nm. The local periods in the X and Y directions are 3020 and 1740 nm, respectively. Measurement results demonstrate the validity of the proposed method for spurious fringes processing.
  Healing of severe pressure injuries (PIs) in patients with multiple comorbidities requires a multifaceted and interdisciplinary approach and includes the use of support surfaces. Published clinical data guiding support surface selection are very limited. Long-term acute care hospitals frequently treat medically complex patients, many with severe PIs.
 
  To compare healing rates in patients with severe PIs on air-fluidized therapy (AFT) or fluid immersion system (FIS) support surfaces.
 
  After obtaining informed consent, patients with a stage 3 or 4 PI were randomized to receive either AFT or FIS in addition to the standard protocol of care. Baseline and weekly wound measurements were obatined using a 3-dimensional camera measurement tool. The required sample size was calculated to be 60.
 
  After the study had started, the long-term acute care hospital admission criteria changed, severely limiting the number of patients who met the study inclusion criteria. Only 4 patients with a stage 4 PI completed the study. Of those, 2 were on an AFT and 2 were on an FIS surface. All wounds reduced in size; 0.12 and 0.57 cm²/day for patients on AFT and 0.68 and 1.34 cm²/day for patients on FIS. All but 1 wound had a reduction in wound volume ranging from -0.2 and 0.97 cm³ to 1.78 and 4.18 cm³/day for patients on AFT and FIS, respectively.
 
  Obtaining much-needed evidence to guide support surface selections for patients with severe PIs is challenging and requires multicenter studies.
 Obtaining much-needed evidence to guide support surface selections for patients with severe PIs is challenging and requires multicenter studies.