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Mariotto I.,New Mexico State University | Gutschick V.P.,The Consulting Consortium
Remote Sensing | Year: 2010

The application of energy balance algorithms to remotely sensed imagery often fails to account for surface roughness variation with diverse land cover, resulting in poor resolution of evapotranspiration (ET) variations. Furthermore, the assumption of a horizontally homogeneous Lambertian surface reflecting energy equally in all directions affects the calculations of albedo and vegetation index. The primary objective of this study is to improve the accuracy of the estimation and discrimination of ET among different land cover types in Southern New Mexico from ASTER datasets, by formulating the spatial variation of non-Lambertian reflectance using a wavelength-dependent Minnaert function. © 2010 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland. Source

Mariotto I.,New Mexico State University | Gutschick V.P.,The Consulting Consortium | Clason D.L.,New Mexico State University
Photogrammetric Engineering and Remote Sensing | Year: 2011

Accurate estimation of evapotranspiration (ET) is difficult to obtain over heterogeneous landscapes presenting spectrally diverse land covers and topographic terrains. The goal of this study is to build advanced remote sensing and surface energy balance algorithms to map ET in a heterogeneous semi-arid area. ET of 12 different land covers is computed by applying the Surface Energy Balance Algorithm for Land (SEBAL) modified for roughness, vegetation index, and topographiccorrected reflectance, with comparison to the JIC model. A GIS raster/vector platform is used to integrate multispectral thermal and reflectance imagery with meteorological, terrain, land-cover, and astronomical data. SEBAL computed with all the modifications showed the best agreement with the ground measurements, compared to the SEBAL versions without any single modification, and it could significantly discriminate ET among 75.8 percent of vegetation types (at threshold differences in ET >0.5 mm/day). SEBAL without any modifications could not discriminate any vegetation types. © 2011 American Society for Photogrammetry and Remote Sensing. Source

Gutschick V.P.,The Consulting Consortium | Sheng Z.,Texas AgriLife Research Center
Agricultural Water Management | Year: 2013

We constructed and validated against eddy-covariance data a model of the fluxes of water vapor, sensible heat, CO2, and radiation in a substantially mature pecan orchard (Carya illinoinensis (Wangenh.)K. Koch) in an arid environment near El Paso, TX, USA. The detailed process-based model is designed for insights into major control points for photosynthetic gain and water use as exerted by canopy structure, leaf physiology, and micrometeorological drivers. Toward this end, it resolves extensive details of leaf micro environments (radiation and scalars) in realistic canopy structures, as well as photosynthetic and respiratory physiology, stomatal control, and water relations from roots to leaves. The model is for a static mid-season canopy, with the ability to link it to dynamics models of development and management. Field flux measurements agreed well with model estimates that were derived using measurable parameters rather than data-fitting. An exception was the measurement-model disparity in sensible heat flux under conditions of strong advection of dry air; the model diagnostics imply a marked insensitivity of pecan stomata to humidity that has not been reported earlier. Formulation and parametrization of most of the physical and physiological processes was robust, shared well between the study site and an alternate site, but gaps are evident in the knowledge of several important processes, primarily in responses to water stress. The study indicates limitations in simpler models, such as those based on constant canopy conductance or light-use efficiency, while offering leads to making more accurate simple models suitable for use in decision support systems, ultimately for stress management under limited water availability. © 2013 Elsevier B.V. Source

Sager P.,The Consulting Consortium | Heilbraun J.,CoreLab Partners | Turner J.R.,Quintiles | Gintant G.,Abbvie Inc. | And 9 more authors.
American Heart Journal | Year: 2013

This White Paper, prepared by members of the Cardiac Safety Research Consortium, discusses several important issues regarding the evaluation of blood pressure (BP) responses to drugs being developed for indications not of a direct cardiovascular (CV) nature. A wide range of drugs are associated with off-target BP increases, and both scientific attention and regulatory attention to this topic are increasing. The article provides a detailed summary of scientific discussions at a Cardiac Safety Research Consortium-sponsored Think Tank held on July 18, 2012, with the intention of moving toward consensus on how to most informatively collect and analyze BP data throughout clinical drug development to prospectively identify unacceptable CV risk and evaluate the benefit-risk relationship. The overall focus in on non-CV drugs, although many of the points also pertain to CV drugs. Brief consideration of how clinical assessment can be informed by nonclinical investigation is also outlined. These discussions present current thinking and suggestions for furthering our knowledge and understanding of off-target drug-induced BP increases and do not represent regulatory guidance. © 2013 Mosby, Inc. Source

Steele A.K.,Aurora University | Lee E.J.,Aurora University | Vestal B.,The Consulting Consortium | Hecht D.,Aurora University | And 5 more authors.
PLoS ONE | Year: 2014

Background: Systemic inflammation is a characteristic of both HIV-1 infection and aging ("inflammaging"). Intestinal epithelial barrier damage (IEBD) and microbial translocation (MT) contribute to HIV-associated inflammation, but their impact on inflammaging remains unclear. Methods: Plasma biomarkers for IEBD (iFABP), MT (LPS, sCD14), T-cell activation (sCD27), and inflammation (hsCRP, IL-6) were measured in 88 HIV-1 uninfected (HIV neg) and 83 treated, HIV-1-infected (HIVpos) adults from 20-100 years old. Results: Age positively correlated with iFABP (r = 0.284, p = 0.008), sCD14 (r = 0.646, p = <0.0001) and LPS (r = 0.421, p = 0.0002) levels in HIVneg but not HIVpos subjects. Age also correlated with sCD27, hsCRP, and IL-6 levels regardless of HIV status. Middle-aged HIVpos subjects had elevated plasma biomarker levels similar to or greater than those of elderly HIVneg subjects with the exception of sCD14. Clustering analysis described an inflammaging phenotype (IP) based on iFABP, sCD14, sCD27, and hsCRP levels in HIVneg subjects over 60 years of age. The IP in HIVneg subjects was used to develop a classification model that was applied to HIVpos subjects to determine whether HIVpos subjects under 60 years of age were IP+. HIV pos IP+ subjects were similar in age to IP- subjects but had a greater risk of cardiovascular disease (CVD) based on Framingham risk score (p = 0.01). Conclusions: We describe a novel IP that incorporates biomarkers of IEBD, MT, immune activation as well as inflammation. Application of this novel IP in HIV-infected subjects identified a group at higher risk of CVD. © 2014 Steele et al. Source

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