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This paper presents the physical basis of the Earth Polychromatic Imaging Camera (EPIC) cloud product algorithms and an initial evaluation of their performance. Since June 2015, EPIC has been providing observations of the sunlit side of the Earth with its 10 spectral channels ranging from the UV to the near-infrared. A suite of algorithms has been developed to generate the standard EPIC Level 2 cloud products that include cloud mask, cloud effective pressure/height, and cloud optical thickness. The EPIC cloud mask adopts the threshold method and utilizes multichannel observations and ratios as tests. Cloud effective pressure/height is derived with observations from the O2 A-band (780 and 764 nm) and B-band (680 and 688 nm) pairs. The EPIC cloud optical thickness retrieval adopts a single-channel approach in which the 780 and 680 nm channels are used for retrievals over ocean and over land, respectively. Comparison with co-located cloud retrievals from geosynchronous earth orbit (GEO) and low earth orbit (LEO) satellites shows that the EPIC cloud product algorithms are performing well and are consistent with theoretical expectations. These products are publicly available at the Atmospheric Science Data Center at the NASA Langley Research Center for climate studies and for generating other geophysical products that require cloud properties as input.

One of fundamental aims of extreme ultraviolet (EUV) lithography is to maximize brightness or conversion efficiency of laser energy to radiation at specific wavelengths from laser produced plasmas (LPPs) of specific elements for matching to available multilayer optical systems. Tin LPPs have been chosen for operation at a wavelength of 13.5 nm. For an investigation of EUV radiation of laser-produced tin plasmas, it is crucial to study the related atomic processes and their evolution so as to reliably predict the optimum plasma and experimental conditions. Here, we present a simplified radiation hydrodynamic model based on the fluid dynamic equations and the radiative transfer equation to rapidly investigate the evolution of radiation properties and dynamics in laser-produced tin plasmas. The self-absorption features of EUV spectra measured at an angle of 45° to the direction of plasma expansion have been successfully simulated and explained, and the evolution of some parameters, such as the plasma temperature, ion distribution and density, expansion size and velocity, have also been evaluated. Our results should be useful for further understanding of current research on extreme ultraviolet and soft X-ray source development for applications such as lithography, metrology and biological imaging.

Synopsis Laser-produced chromium (Cr) plasmas have been measured by using a temporal-spatially resolved laser-produced plasma emission spectroscopy technique. The emission peaks in the wavelength range of 6.5-15 nm were identified from the 3p-4d, 5d, and 3p-4s transition lines from Cr5+ to Cr10+ ions with aid of Cowan and Flexible Atomic Code (FAC) atomic structure calculations, and through comparative analysis between experimental and simulated spectra.

This study aimed to compare three different surgery approaches for pituitary adenoma excision. A total of 162 patients underwent pituitary adenoma excision through the sphenoid sinus approach. Among patients, five underwent the sublabio-septo-sphenoidal approach (abbreviated as "sublabio approach"), seven underwent the sphenoid sinus approach and 150 underwent the nasal septum approach. The operative cases that underwent the sublabio approach showed severe surgical trauma because of the complicated operation procedure. The sphenoid sinus approach was relatively easy to operate, but the procedure may confuse an inexperienced operator, which occurred in two out of seven cases in our study. The anatomical landmark was clearer under the nasal septum approach than the other approaches. Thus, operators were less likely to make mistakes during the nasal septum operation. In our study, a success rate of 100% was obtained for the 68 patients who underwent nasal septum operation. The nasal septum approach was suitable for most patients with pituitary adenoma. The hierarchy of the anatomy was distinctive and easily controlled. Thus, the entire nasal septum operation was relatively safe, effective and minimally invasive and can be completed by an operator with sufficient anatomical knowledge and operation skill.

SUMMARY New methods for the treatment of solar radiative transfer through overlapping and inhomogeneous clouds are presented. First, a new approach to cloud overlap is shown. For the adjacent cloud blocks, the traditional maximum overlap can be relaxed to a mixture of maximum and random overlap treatments for layers that are adjacent but not fully correlated. Second, a new radiative-transfer algorithm has been developed to deal with these various cloud overlap circumstances that is simple enough for implementation in a general-circulation model (GCM). When compared to appropriate benchmark calculations, we find that this new method can produce accurate results in heating rates and fluxes with relative errors generally less than 8%. Third, a new and very simple approach to treating radiative transfer through a cloud with horizontal subgrid-scale inhomogeneities is developed. This approach uses an optical-depth scaling technique to represent the subgrid-scale inhomogeneity. Finally, by combining all of the above elements, we provide a new algorithm for the combined treatment of cloud overlap and inhomogeneity and we show that it yields very reasonable accuracies for heating rates and fluxes. Through benchmark comparisons, we show that this new algorithm provides significant improvement over existing schemes in GCMs.

A metal-isolator-metal (MIM) metamaterial absorber with embedded graphene shows tunable at mid-infrared frequency regime. We report tunable absorption spectra of the MIM structure for different Fermi levels of graphene.

The Cloud and Land Surface Interaction Campaign is a field experiment designed to collect a comprehensive data set that can be used to quantify the interactions that occur between the atmosphere, biosphere, land surface, and subsurface. A particular focus will be on how these interactions modulate the abundance and characteristics of small and medium size cumuliform clouds that are generated by local convection. These interactions are not well understood and are responsible for large uncertainties in global climate models, which are used to forecast future climate states. The campaign will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of Cloud and Land Surface Interaction Campaign includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Mesoscale and microscale structures will be sampled with a variety of aircraft,more » surface, and radar observations.« less

The Cloud and Land Surface Interaction Campaign (CLASIC) will be conducted from June 8 to June 30, 2007, at the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. Data will be collected using eight aircraft equipped with a variety of specialized sensors, four specially instrumented surface sites, and two prototype surface radar systems. The architecture of CLASIC includes a high-altitude surveillance aircraft and enhanced vertical thermodynamic and wind profile measurements that will characterize the synoptic scale structure of the clouds and the land surface within the ACRF SGP site. Mesoscale and microscale structures will be sampled with a variety of aircraft, surface, and radar observations. An overview of the measurement platforms that will be used during the CLASIC are described in this report. The coordination of measurements, especially as it relates to aircraft flight plans, will be discussed in the CLASIC Implementation Plan.

Tuberculosis in the abdominal lymph nodes may be difficult to distinguish from lymphomas. This study evaluated specific CT imaging criteria for differentiating these entities.We retrospectively reviewed the anatomic distribution and CT enhancement patterns of disease in 69 patients, 26 (38%) with tuberculosis and 43 (62%) with untreated lymphomas involving abdominal lymph nodes. Of the patients with tuberculosis, five (19%) had disseminated disease and 21 (81%) had nondisseminated disease. Of the patients with lymphomas, 16 (37%) had Hodgkin's disease and 27 (63%) had non-Hodgkin's lymphoma.Disseminated and nondisseminated tuberculosis involved predominantly lesser omental, mesenteric, anterior pararenal, and upper paraaortic lymph nodes. Lower paraaortic lymph nodes were involved more often in Hodgkin's disease (15 patients [94%]), non-Hodgkin's lymphoma (24 patients [89%]), and disseminated tuberculosis (five patients [100%]) than in nondisseminated tuberculosis (one patient [5%]). Mesenteric lymph nodes were involved more often in disseminated tuberculosis (four patients [80%]) and nondisseminated tuberculosis (11 patients [52%]) than in Hodgkin's disease (one patient [6%]) (p.01). Anatomic distribution was not different between disseminated tuberculosis and non-Hodgkin's lymphoma. Tuberculous lymphadenopathy commonly showed peripheral enhancement, frequently with a multilocular appearance, whereas lymphomatous adenopathy characteristically showed homogeneous attenuation (14 patients [87.5%] with Hodgkin's disease and 19 patients [70%] with non-Hodgkin's lymphoma [p.01]).Our findings indicate that the anatomic distribution and specific enhancement patterns of lymphadenopathy seen on contrast-enhanced CT can be useful in differentiating between tuberculosis and untreated lymphomas of the abdominal lymph nodes.