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Aspergillus tubingensis and Talaromyces islandicus Solubilize Rock Phosphate Under Saline and Fungicide Stress and Improve Zea mays Growth and Phosphorus Nutrition
No full textThe purpose of this study was to evaluate the capability of Aspergillus tubingensis and Talaromyces islandicus to solubilize inorganic phosphorus sources, their activity under abiotic stress, and the enhancement of P availability in soils and plant growth. The P-solubilizing capability and acidification mechanism of the strains were assessed in vitro using tricalcium phosphate and rock phosphate. Independent assays were conducted with rock phosphate under NaCl and fungicides carbendazim, chlorothalonil, and propamocarb hydrochloride using a factorial design. Thereafter, the effects of fungal inoculations in rock phosphate–amended soil and P nutrition of Zea mays were assessed in a greenhouse experiment. Both fungi solubilized P in vitro via acidification through the exudation of acetic, citric, lactic, malic, quinic, and succinic acids. The P-solubilizing efficiency of A. tubingensis was maintained above 97.5% under 0.5 to 3.0% NaCl, up to 28.7% in the treatment with carbendazim, up to 5.3% with chlorothalonil, and above 96.5% with propamocarb hydrochloride; while T. islandicus efficiency decreased to 45.2% in a NaCl concentration-dependent trend, and maintained it above 80% in the fungicide treatments. The inoculation with A. tubingensis increased the available P in the amended soil by up to 65% after 30 days and resulted in 87% higher foliar P content, 111% greater plant height, and 25% greater dry weight of maize shoots. Similarly, T. islandicus contributed to these parameters in 55, 67, 90, and 17%, respectively. These findings suggest their potential as qualified phosphorus solubilizing microorganisms to develop novel and sustainable approaches for P fertilization in agriculture. © 2020, Sociedad Chilena de la Ciencia del Suelo
Evaluation of sustainable development in the sub-regions of Antioquia (Colombia) using multi-criteria composite indices: A tool for prioritizing public investment at the subnational level
No full textThis article comparatively evaluates sustainable development levels in the nine sub-regions of the department of Antioquia (Colombia), using composite indices. Given the complexity and the diversity of sustainable development aspects, a multi-criteria evaluation framework was developed and organized at different stages. These stages included defining a conceptual framework; choosing relevant indicators for evaluation; completing a multivariate analysis to reduce indicators; standardizing data; weighting indicators through the process of analytical hierarchy, and finally, aggregating the indicators. The results indicate that the Aburra Valley and East sub-regions are at the stable sustainable development level (medium-high); the West, North, Southwest, Middle Magdalena, Northeast, and Uraba sub-regions are at the unstable sustainable development level (medium-medium); and Low Cauca is at the unstable level (medium-low), which gives the true picture of the disparity between the sub-regions. The disaggregated results allowed us to identify public investment priorities for each of the sub-regions studied. Thus, the use of composite indices is presented as a high-level technical tool that supports governmental decision-making at a subnational level. © 2019 Elsevier B.V
Improved Gait Speed Calculation via Modulation Spectral Analysis of Noisy Accelerometer Data
No full textChronic diseases among older adults carry a heavy burden on a country's healthcare system and economy. As such, there is a critical need for the development of cost-effective, technology-based tools that can be scaled to meet the needs of older adults. Gait speed, for example, is an important predictor of change in functional status and health outcomes in older adults. There is no universally accepted method for measuring gait speed in clinical practice and research, and differences in methods may influence the observed associations between gait speed and health. Moreover, existing methods are sensitive to artifacts, which are present in burgeoning low-cost wearable devices. To overcome this limitation, this paper proposes an artifact-robust gait speed calculation method using spectrooral signal processing of accelerometer data. To this end, a new so-called modulation domain gait speed (MD-GS) metric is proposed and tested on data collected from forty older adults performing a 400-meter walk test with a sensor placed on a waist-worn belt. Average gait speed calculation is performed for each participant. Experimental results showed the proposed method achieved very high correlation ( ρ =0.98 ) with ground truth gait speeds, as well as low errors and error variability (0.05±0.14) m/s, thus substantially outperforming gait speed calculation using a well-known kinematic model. The increased robustness against artifacts, make it a promising solution for aging-in-home applications based on low-cost wearable devices. © 2001-2012 IEEE
Numerical modeling parameters by the finite elements method for a hollow concrete block under uniaxial compression load [Parámetros de modelación numérica mediante elementos finitos para un bloque hueco de concreto bajo carga de compresión uniaxial]
No full textThe growing demand in modern industry requires increasingly greater demands on the structural performance of the employed materials and, therefore, it has been seen that is necessary to implement a series of numerical models that allow to adequately predict the mechanical behavior of the materials that are subjected to severe loading conditions. All these numerical models require, as input parameters, the main elastic and plastic behavior coefficients of the materials, which in the case of concrete and steel, are well known parameters that are already tabulated in most materials mechanics texts. In the case of structural masonry, the main parameters for the numerical models are very limited in the state of the art, and they are mostly obtained from laboratory tests of the masonry units, which in many cases do not faithfully represent the structural performance of the raw material that constitutes the unit, mainly due to the confinement generated by the geometry of the units and the different volumetric strain conditions to which the same masonry unit is subjected under the application of a punctual load. In the present research a numerical model by means of finite elements is developed. The model allows to establish a correlation of the linear and nonlinear properties of a hollow block of concrete with the experimental results obtained from a set of uniaxial compression laboratory tests. The results of this research will be used in the future for the analysis of masonry structures, especially the post-tensioned type. © 2020 AISTI
About validation-comparison of burned area products
No full textThis paper proposes a validation-comparison method for burned area (BA) products. The technique considers: (1) bootstrapping of scenes for validation-comparison and (2) permutation tests for validation. The research focuses on the tropical regions of Northern Hemisphere South America and Northern Hemisphere Africa and studies the accuracy of the BA products: MCD45, MCD64C5.1, MCD64C6, Fire CCI C4.1, and Fire CCI C5.0. The first and second parts consider methods based on random matrix theory for zone differentiation and multiple ancillary variables such as BA, the number of burned fragments, ecosystem type, land cover, and burned biomass. The first method studies the zone effect using bootstrapping of Riemannian, full Procrustes, and partial Procrustes distances. The second method explores the validation by using distance permutation tests under uncertainty. The results refer to Fire CCI 5.0 with the best BA description, followed by MCD64C6, MCD64C5.1, MCD45, and Fire CCI 4.1. It was also found that biomass, total BA, and the number of fragments affect the BA product accuracy. © 2020 by the authors. Licensee MDPI, Basel, Switzerland
On the Optimal Control of Multidimensional Dynamic Systems Evolving with State Suprema
No full textThis paper constitutes a further generalization of the numerical solution approaches to Optimal Control Problems (OCPs) of systems evolving with state suprema. We study multidimensional control systems described by differential equations with the sup-operator in the right hand sides. A specific state-observer model and the linear type feedback control design under consideration imply a resulting closed-loop system that can formally be characterized as a multidimensional Functional Differential Equation (FDE) with delays. We study OCPs associated with the obtained FDEs and establish some fundamental solution properties of this class of problems. A particular structure of the resulting dynamic optimization problem makes it possible to consider the originally given sophisticated OCP in the framework of the nonlinear separate programming in some Euclidean spaces. This fact makes it possible to apply effective and relative simple splitting type computational algorithms to the initially given sophisticated OCPs for systems evolving with state suprema. © 2018 IEEE
Phosphate removal from aqueous solutions by heat treatment of eggshell and palm fiber
No full textPhosphate removal from wastewater and the correspondent sustainable technologies are urgent issues to solve since phosphorous causes eutrophication of water sources. The effect of heat treatment on the mixture eggshell (ES), rich in calcium carbonate, with fiber palm (F), rich in carbonaceous material for phosphate removal is here reported focusing on the effects of temperature and F/ES ratio. The gases obtained from the F pyrolysis process help to improve the Ca(OH)2 formation. In samples with a ES/F ratio of 1/10 (ESF-1:10) the CaCO3 is mainly transformed into Ca(OH)2 (83 %) at 600 °C instead of 800 °C. The obtained solids were employed for phosphate removal from aqueous solutions and characterized before and after P removal. The ESF-1:10 sample pyrolyzed at 600 °C exhibited the best adsorption performance (48.3 %) at 2 h while ES showed 6.5 % at the same experimental conditions. The pseudo-second-order model kinetic and Langmuir model isotherm provided better-fitting models for the adsorption behavior of P. The adsorption capacity using Langmuir model was 72.0 mg g-1, and the pseudo-second-order kinetic model assumes that the removal process of adsorbate is controlled by chemical adsorption. These results show that the Ca(OH)2 is responsible for the phosphate removal by ligand exchange followed by precipitation mechanism leading to the formation of apatite. © 2020 Elsevier Ltd
Physicochemical Characterization of Airborne Particulate Matter in Medellín, Colombia, and its Use in an In Silico Study of Ventricular Action Potential
No full textParticulate matter (PM) is a complex mixture of particles that changes over time and from place to place; however, most PM is caused by the fuel combustion of motor vehicles and industry. PM is associated with acute and chronic illnesses, such as pulmonary and cardiovascular diseases. Medellín is one of the most polluted cities in Latin America. Therefore, the physicochemical characterization of its PM is necessary to understand its composition and effect on human health. In this study, PM was characterized by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) analysis, Fourier infrared spectroscopy (FTIR), inductivity-coupled plasma optical emission spectrometry (ICP-OES), and thermogravimetric analysis (TGA) in order to evaluate its morphology and chemical composition. The SEM of the PM exhibited primary particles and agglomerates. The size of the particles ranged between 0.056 and 4.5 μm. The EDS revealed elements such as carbon, silicon, calcium, lead, and iron. Furthermore, carbon monoxide, carbon dioxide, and carbonyl and aliphatic functional groups were observed by means of FTIR. Additionally, weight losses associated with volatile matter and elemental carbon were identified in the TGA analysis. The TGA and FTIR confirmed the presence of fuel and lubricant traces. Subsequently, lead was selected among the most common components in the PM in order to conduct an in silico study into its effect on ventricular activity. Lead showed a pro-arrhythmic effect by shortening the duration of the action potential under normal electrophysiological conditions, which could be associated with cardiovascular diseases. © 2020, Springer Nature Switzerland AG
The software development as a digital enabler for the 4th industrial revolution [El desarrollo de software como habilitador digital para la 4ta revolución industrial]
No full text[No abstract available
The disease as sign and the symbolic forms of the sick body on the horizon of comprehension d the dermatology nineteenth [La enfermedad como signo y las formas simbólicas del cuerpo enfermo en el horizonte de comprensión de la dermatología decimonónica1 hilderman cardona-rodas]
No full textThe clinical dermatology of the nineteenth century bases and displays a thought by similarity in an aesthetic representation of what can be understood as disease. Thus, the pathological surfaces provide a material of reflection and appropriation of the sick body where body, language and event converge to give meaning to the alterations that converge in the pathological state. This text reflects on these symbolic forms of naming the disease that occur in descriptions, clinical observations, treaties of dermatology, Atlas of pathological anatomy or iconographic albums of the nineteenth century, where it is possible to see a regime of visualization of the pathological that reveals itself in the medical perception of the lesion and its location. The analysis of skin diseases that disfigure the face from some clinical and iconographic records from the end of the 19th century puts into play a link between image and word in terms of dermatological efficacy in ways of capturing the experience of the disease, which has the sick body as a theater of performative sensitivity. © 2020, UNIV SAOPAULO. All rights reserved