3,767 research outputs found

    Proximal hyperspectral sensing and data analysis approaches for field-based plant phenomics

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    Field-based plant phenomics requires robust crop sensing platforms and data analysis tools to successfully identify cultivars that exhibit phenotypes with high agronomic and economic importance. Such efforts will lead to genetic improvements that maintain high crop yield with concomitant tolerance to environmental stresses. The objectives of this study were to investigate proximal hyperspectral sensing with a field spectroradiometer and to compare data analysis approaches for estimating four cotton phenotypes: leaf water content (Cw), specific leaf mass (Cm), leaf chlorophyll a+b content (Cab), and leaf area index (LAI). Field studies tested 25 Pima cotton cultivars grown under well-watered and water-limited conditions in central Arizona from 2010 to 2012. Several vegetation indices, including the normalized difference vegetation index (NDVI), the normalized difference water index (NDWI), and the physiological (or photochemical) reflectance index (PRI) were compared with partial least squares regression (PLSR) approaches to estimate the four phenotypes. Additionally, inversion of the PROSAIL plant canopy reflectance model was investigated to estimate phenotypes based on 3.68 billion PROSAIL simulations on a supercomputer. Phenotypic estimates from each approach were compared with field measurements, and hierarchical linear mixed modeling was used to identify differences in the estimates among the cultivars and water levels. The PLSR approach performed best and estimated Cw,Cm,Cab, and LAI with root mean squared errors (RMSEs) between measured and modeled values of 6.8%, 10.9%, 13.1%, and 18.5%, respectively. Using linear regression with the vegetation indices, no index estimated Cw,Cm,Cab, and LAI with RMSEs better than 9.6%, 16.9%, 14.2%, and 28.8%, respectively. PROSAIL model inversion could estimate Cab and LAI with RMSEs of about 16% and 29%, depending on the objective function. However, the RMSEs for Cw and Cm from PROSAIL model inversion were greater than 30%. Compared to PLSR, advantages to the physically-based PROSAIL model include its ability to simulate the canopy's bidirectional reflectance distribution function (BRDF) and to estimate phenotypes from canopy spectral reflectance without a training data set. All proximal hyperspectral approaches were able to identify differences in phenotypic estimates among the cultivars and irrigation regimes tested during the field studies. Improvements to these proximal hyperspectral sensing approaches could be realized with a high-throughput phenotyping platform able to rapidly collect canopy spectral reflectance data from multiple view angles

    The C-terminal domain of TPX2 is made of alpha-helical tandem repeats

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    Background: TPX2 (Targeting Protein for Xklp2) is essential for spindle assembly, activation of the mitotic kinase Aurora A and for triggering microtubule nucleation. Homologs of TPX2 in Chordata and plants were previously identified. Currently, proteins of the TPX2 family have little structural information and only small parts are covered by defined protein domains. Methods: We have used computational sequence analyses and structural predictions of proteins of the TPX2 family, supported with Circular Dichroism (CD) measurements. Results: Here, we report our finding that the C-terminal domain of TPX2, which is responsible of its microtubule nucleation capacity and is conserved in all members of the family, is actually formed by tandem repeats, covering well above 2/3 of the protein. We propose that this region forms a flexible solenoid involved in protein-protein interactions. Structural prediction and molecular modeling, combined with Circular Dichroism (CD) measurements reveal a predominant alpha-helical content. Furthermore, we identify full length homologs in fungi and shorter homologs with a different domain organization in diptera (including a paralogous expansion in Drosophila). Conclusions: Our results, represent the first computational and biophysical analysis of the TPX2 proteins family and help understand the structure and evolution of this conserved protein family to direct future structural studies

    Epithelial Ovarian Cancer Diagnosis of SecondHarmonic Generation Images: A Semiautomatic Collagen Fibers Quantification Protocol

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    A vast number of human pathologic conditions are directly or indirectly related to tissular collagen structure remodeling. The nonlinear optical microscopy second-harmonic generation has become a powerful tool for imaging biological tissues with anisotropic hyperpolarized structures, such as collagen. During the past years, several quantification methods to analyze and evaluate these images have been developed. However, automated or semiautomated solutions are necessary to ensure objectivity and reproducibility of such analysis. This work describes automation and improvement methods for calculating the anisotropy (using fast Fourier transform analysis and the gray-level co-occurrence matrix). These were applied to analyze biopsy samples of human ovarian epithelial cancer at different stages of malignancy (mucinous, serous, mixed, and endometrial subtypes). The semiautomation procedure enabled us to design a diagnostic protocol that recognizes between healthy and pathologic tissues, as well as between different tumor types.Fil: Zeitoune, Angel Alberto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro de Investigaciones y Transferencia de Entre RĂ­os. Universidad Nacional de Entre RĂ­os. Centro de Investigaciones y Transferencia de Entre RĂ­os; ArgentinaFil: Luna, Johana S. J.. Universidad Nacional de Entre RĂ­os. Facultad de IngenierĂ­a; ArgentinaFil: Sanchez Salas, Kynthia. Universidad Nacional de Entre RĂ­os. Facultad de IngenierĂ­a; ArgentinaFil: Erbes, Luciana Ariadna. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro de Investigaciones y Transferencia de Entre RĂ­os. Universidad Nacional de Entre RĂ­os. Centro de Investigaciones y Transferencia de Entre RĂ­os; ArgentinaFil: Cesar, Carlos L.. Universidade Federal do CearĂĄ; Brasil. National Institute of Science and Technology on Photonics Applied to Cell Biology; BrasilFil: Andrade, Liliana A. L. A.. Universidade Estadual de Campinas; BrasilFil: Carvahlo, Hernades F.. Universidade Estadual de Campinas; Brasil. National Institute of Science and Technology on Photonics Applied to Cell Biology; BrasilFil: Bottcher Luiz, FĂĄtima. Universidade Estadual de Campinas; Brasil. National Institute of Science and Technology on Photonics Applied to Cell Biology; BrasilFil: Casco, Victor Hugo. Universidad Nacional de Entre RĂ­os. Facultad de IngenierĂ­a; ArgentinaFil: Adur, Javier Fernando. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro de Investigaciones y Transferencia de Entre RĂ­os. Universidad Nacional de Entre RĂ­os. Centro de Investigaciones y Transferencia de Entre RĂ­os; Argentina. Universidad Nacional de Entre RĂ­os. Facultad de IngenierĂ­a; Argentin

    Silver nanoparticles-composing alginate/gelatine hydrogel improves wound healing in vivo

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    Polymer hydrogels have been suggested as dressing materials for the treatment of cutaneous wounds and tissue revitalization. In this work, we report the development of a hydrogel composed of natural polymers (sodium alginate and gelatin) and silver nanoparticles (AgNPs) with recognized antimicrobial activity for healing cutaneous lesions. For the development of the hydrogel, different ratios of sodium alginate and gelatin have been tested, while different concentrations of AgNO3 precursor (1.0, 2.0, and 4.0 mM) were assayed for the production of AgNPs. The obtained AgNPs exhibited a characteristic peak between 430450 nm in the ultraviolet-visible (UVVis) spectrum suggesting a spheroidal form, which was confirmed by Transmission Electron Microscopy (TEM). Fourier Transform Infra-red (FTIR) analysis suggested the formation of strong intermolecular interactions as hydrogen bonds and electrostatic attractions between polymers, showing bands at 2920, 2852, 1500, and 1640 cm1. Significant bactericidal activity was observed for the hydrogel, with a Minimum Inhibitory Concentration (MIC) of 0.50 ”g/mL against Pseudomonas aeruginosa and 53.0 ”g/mL against Staphylococcus aureus. AgNPs were shown to be non-cytotoxic against fibroblast cells. The in vivo studies in female Wister rats confirmed the capacity of the AgNP-loaded hydrogels to reduce the wound size compared to uncoated injuries promoting histological changes in the healing tissue over the time course of wound healing, as in earlier development and maturation of granulation tissue. The developed hydrogel with AgNPs has healing potential for clinical applications.This research received funding from the Coordenação Aperfeiçoamento de Pessoal de Nivel Superior (CAPES), Fundação de Amparo à Pesquisa do Estado de Sergipe (FAPITEC), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, #443238/2014-6, #470388/2014-5), and from the Portuguese Science and Technology Foundation (FCT) projects M-ERA-NET/0004/2015 (PAIRED) and UIDB/04469/2020 (strategic fund).info:eu-repo/semantics/publishedVersio

    Engineering aspects of hydrothermal pretreatment: from batch to continuous operation, scale-up and pilot reactor under biorefinery concept

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    Different pretreatments strategies have been developed over the years mainly to enhance enzymatic cellulose degradation. In the new biorefinery era, a more holistic view on pretreatment is required to secure optimal use of the whole biomass. Hydrothermal pretreatment technology is regarded as very promising for lignocellulose biomass fractionation biorefinery and to be implemented at the industrial scale for biorefineries of second generation and circular bioeconomy, since it does not require no chemical inputs other than liquid water or steam and heat. This review focuses on the fundamentals of hydrothermal pretreatment, structure changes of biomass during this pretreatment, multiproduct strategies in terms of biorefinery, reactor technology and engineering aspects from batch to continuous operation. The treatise includes a case study of hydrothermal biomass pretreatment at pilot plant scale and integrated process design.The authors gratefully thank the Secretary of Public Education ofMexico – Mexican Science and Technology Council (SEP-CONACYT,Mexico) for the Basic Science Project -2015-01 (Ref. 254808), EnergySustainability Fund 2014-05 (CONACYT-SENER), Mexican Centre forInnovation in Bioenergy (Cemie-Bio), Cluster of Bioalcohols (Ref.249564) and the BMBF for the financial support (reference number:031B0660A).info:eu-repo/semantics/publishedVersio

    Water scarcity footprint of cocoa irrigation in Bahia.

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    This study simulated the water scarcity footprint (WSF) of cocoa irrigation in municipalities considered suitable for cocoa growing in the state of Bahia, according to agro climatic zoning. Irrigation demand was calculated using the model proposed by FAO (Food and Agriculture Organization of the United Nations). Subsequently, impact on water scarcity was calculated using the product of crop irrigation demand and water scarcity characterization factors of the regionalized AWARE method for Brazil. The WSF in Bahia ranged between 0.28 and 646.5 mÂł of water per kilo of cocoa produced. From the defined scale, of the 417 municipalities in Bahia suitable for growing cocoa, 59% have a 'low' footprint, 18% 'medium', 10% 'high', and 12% have a 'very high' footprint. Based on these results, it is suggested that areas with lower WSF are a priority in the expansion of cocoa to avoid a possible compromise of other essential demands of the municipalities. In addition, irrigation should avoid waste, especially in regions with high levels of water scarcity. The results show that the inclusion of the WSF in agroclimatic zoning can contribute to the process of identifying potential and critical regions for new crops and the expansion of others

    The Structure and Dynamics of the Upper Chromosphere and Lower Transition Region as Revealed by the Subarcsecond VAULT Observations

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    The Very high Angular resolution ULtraviolet Telescope (VAULT) is a sounding rocket payload built to study the crucial interface between the solar chromosphere and the corona by observing the strongest line in the solar spectrum, the Ly-a line at 1216 {\AA}. In two flights, VAULT succeeded in obtaining the first ever sub-arcsecond (0.5") images of this region with high sensitivity and cadence. Detailed analyses of those observations have contributed significantly to new ideas about the nature of the transition region. Here, we present a broad overview of the Ly-a atmosphere as revealed by the VAULT observations, and bring together past results and new analyses from the second VAULT flight to create a synthesis of our current knowledge of the high-resolution Ly-a Sun. We hope that this work will serve as a good reference for the design of upcoming Ly-a telescopes and observing plans.Comment: 28 pages, 11 figure
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