Large-area, wide-angle, spectrally selective plasmonic absorber

A simple metamaterial-based wide-angle plasmonic absorber is introduced, fabricated, and experimentally characterized using angle-resolved infrared spectroscopy. The metamaterials are prepared by nano-imprint lithography, an attractive low-cost technology for making large-area samples. The matching of the metamaterial's impedance to that of vacuum is responsible for the observed spectrally selective "perfect" absorption of infrared light. The impedance is theoretically calculated in the single-resonance approximation, and the responsible resonance is identified as a short-range surface plasmon. The spectral position of the absorption peak (which is as high as 95%) is experimentally shown to be controlled by the metamaterial's dimensions. The persistence of "perfect" absorption with variable metamaterial parameters is theoretically explained. The wide-angle nature of the absorber can be utilized for sub-diffraction-scale infrared pixels exhibiting spectrally selective absorption/emissivity.Comment: 7 pages, 6 figures, submitted to Phys. Rev.

MODEL SELECTION FOR SYSTEM IDENTIFICATION BY MEANS OF ARTIFICIAL NEURAL NETWORKS

ABSTRACT: System identification is one main task in modern deformation analysis. If the physical structure of the monitored object is unknown or not accessible the system identification is performed in a behavioural framework. Therein the relations between input and output signals are formulated on the basis of regression models. Artificial neural networks (ANN) are a very flexible tool for modelling especially non-linear relationships between the input and the output measures. The universal approximation theorem ensures that every continuous relation can be modelled with this approach. However, some structural aspects of the ANN-based models, like the number of hidden nodes or the number of data needed to obtain a good generalisation, remain unspecified in the theorem. Therefore, one faces a model selection problem. In this article the methodology of modelling the deformations of a lock occurring due to water level and temperature changes is described. We emphasize the aspect of model selection, by presenting and discussing the results of various approaches for the determination of the number of hidden nodes. The first one is cross-validation. The second one is a weight deletion technique based on the exact computation of the Hessian matrix. Finally, the third method has a rigorous theoretical background and is based on the capacity concept of a model structure. The results of these methods are compared from the viewpoint of generalisation

Coulomb plasmas in outer envelopes of neutron stars

Outer envelopes of neutron stars consist mostly of fully ionized, strongly coupled Coulomb plasmas characterized by typical densities about 10^4-10^{11} g/cc and temperatures about 10^4-10^9 K. Many neutron stars possess magnetic fields about 10^{11}-10^{14} G. Here we briefly review recent theoretical advances which allow one to calculate thermodynamic functions and electron transport coefficients for such plasmas with an accuracy required for theoretical interpretation of observations.Comment: 4 pages, 2 figures, latex2e using cpp2e.cls (included). Proc. PNP-10 Workshop, Greifswald, Germany, 4-9 Sept. 2000. Accepted for publication in Contrib. Plasma Phys. 41 (2001) no. 2-

Assessment of antibiotic de-escalation by spectrum score in patients with nosocomial pneumonia: A single-center, retrospective cohort study

Background: Hospital-acquired and ventilator-associated pneumonia (HAP/VAP) cause significant mortality. Guidelines recommend empiric broad-spectrum antibiotics followed by de-escalation (DE). This study sought to assess the impact of DE on treatment failure. Methods: This single-center retrospective cohort study screened all adult patients with a discharge diagnosis code for pneumonia from 2016 to 2019. Patients were enrolled if they met predefined criteria for HAP/VAP ≥48 hours after admission. Date of pneumonia diagnosis was defined as day 0. Spectrum scores were calculated, and DE was defined as a score reduction on day 3 versus day 1. Patients with DE were compared to patients with no de-escalation (NDE). The primary outcome was composite treatment failure, defined as all-cause mortality or readmission for pneumonia within 30 days of diagnosis. Results: Of 11860 admissions screened, 1812 unique patient-admissions were included (1102 HAP, 710 VAP). Fewer patients received DE (876 DE vs 1026 NDE). Groups were well matched at baseline, although more patients receiving DE had respiratory cultures ordered (56.6% vs 50.6%, Conclusions: De-escalation and NDE resulted in similar rates of 30-day treatment failure; however, DE was associated with fewer antibiotic days, episodes o

Evaluation of a hybrid antimicrobial restriction process at a large academic medical center

We conducted a retrospective review of a hybrid antimicrobial restriction process demonstrating adherence to appropriate use criteria in 72% of provisional-only orders, in 100% of provisional orders followed by ID orders, and in 97% of ID-initiated orders. Therapy interruptions occurred in 24% of provisional orders followed by ID orders

Исследование характеристик ядерных трековых мембран для создания дренажной системы в лечении глаукомы

In this article has been researched possibility of using nuclear track membrane for fluid transport in the implementation and maintenance of the cornea weaklydehydrated state

Identifying Mechanisms of Normal Cognitive Aging Using a Novel Mouse Genetic Reference Panel.

Developing strategies to maintain cognitive health is critical to quality of life during aging. The basis of healthy cognitive aging is poorly understood; thus, it is difficult to predict who will have normal cognition later in life. Individuals may have higher baseline functioning (cognitive reserve) and others may maintain or even improve with age (cognitive resilience). Understanding the mechanisms underlying cognitive reserve and resilience may hold the key to new therapeutic strategies for maintaining cognitive health. However, reserve and resilience have been inconsistently defined in human studies. Additionally, our understanding of the molecular and cellular bases of these phenomena is poor, compounded by a lack of longitudinal molecular and cognitive data that fully capture the dynamic trajectories of cognitive aging. Here, we used a genetically diverse mouse population (B6-BXDs) to characterize individual differences in cognitive abilities in adulthood and investigate evidence of cognitive reserve and/or resilience in middle-aged mice. We tested cognitive function at two ages (6 months and 14 months) using y-maze and contextual fear conditioning. We observed heritable variation in performance on these traits