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Evaluating the use of Beer's law for estimating light interception in canopy architectures with varying heterogeneity and anisotropy
Light interception in plant canopies is most commonly estimated using a simple one-dimensional turbid medium model (i.e., Beer's law). Inherent in this class of models are assumptions that vegetation is uniformly distributed in space (homogeneous) and in many cases that vegetation orientation is uniformly distributed (isotropic). It is known that these assumptions are violated in a wide range of canopies, as real canopies commonly have heterogeneity at multiple scales and almost always have highly anisotropic leaf angle distributions. However, it is not quantitatively known under what conditions these assumptions become problematic given the difficulty of robustly evaluating model results for a range of canopy architectures. In this study, assumptions of vegetation homogeneity and isotropy were evaluated under clear sky conditions for a range of virtually-generated crop canopies with the aid of a detailed three-dimensional, leaf-resolving radiation model. Results showed that Beer's law consistently over predicted light interception for all canopy configurations. For canopies where the plant spacing was comparable to the plant height, Beer's law performed poorly, and over predicted daily intercepted sunlight by up to ∼115%. For vegetation with a highly anisotropic leaf inclination distribution but a relatively isotropic leaf azimuth distribution, the assumption of canopy isotropy (i.e., G = 0.5) resulted in relatively small errors. However, if leaf elevation and azimuth were both highly anisotropic, the assumption of canopy isotropy could introduce significant errors depending on the orientation of the azimuthal anisotropy with respect to the sun's path
A three-by-three matrix spectral problem for AKNS hierarchy and its binary Nonlinearization
A three-by-three matrix spectral problem for AKNS soliton hierarchy is
proposed and the corresponding Bargmann symmetry constraint involved in Lax
pairs and adjoint Lax pairs is discussed. The resulting nonlinearized Lax
systems possess classical Hamiltonian structures, in which the nonlinearized
spatial system is intimately related to stationary AKNS flows. These
nonlinearized Lax systems also lead to a sort of involutive solutions to each
AKNS soliton equation.Comment: 21pages, in Late
Espais propis de circulació. Aproximació al pensar, al fer i al ser d’un equip d’educadores socials
Treballs Finals de Grau d'Educació Social, Facultat d'Educació, Universitat de Barcelona, Curs: 2015-2016, Tutora: Ana Mª Novella Cámara[cat] Una recerca és un procés d’exploració, d’aprenentatge i també de creació. En aquest darrer tret característic és on es centra aquest treball: en la creació col·lectiva com a forma i espai de recerca.
Sovint els equips promotors d’iniciatives socials no posen èmfasi en pensar -se a ells mateixos i les seves pràctiques. Aquesta revisió col·lectiva pot ajudar als equips a millorar i a prendre consciència de la seva trajectòria, del seu posicionament ideològic respecte el projecte que promouen.
Aquesta recerca parteix d’una experiència concreta com la de l’Associació Circula Cultura. Fruit de la necessitat de revisió s’ha dut a terme un procés de reflexió sobre la pràctica que ens permet aproximar-nos al pensar, al fer i al ser de l’equip promotor en un projecte sociocomunitari.
Durant el procés de recerca s’han posat en pràctica dinàmiques creatives posant de manifest la importància l’experiència viscuda com a font de coneixement.[eng] A research is a process of exploration, learning and creation. This work is focused in this last distinctive feature: in the collective creation as a way and a space of research.
Often, promoter teams of social initiatives don’t emphasize in thinking (about) themselves and their practices. This collective review can help the teams improve and raise awareness of their own trajectories; their ideological positions regarding the project they enhance.
This investigation parts from the specific experience of the Circula Cultura association. Due to a need for revision, a process of reflection about the practice has been carried out in order to allow us to think, to do and to be as a team promoting a social community project.
During the research process, creative dynamics have been brought to practice highlighting the importance of experience as a source of knowledge
Nutritional value and antioxidant activity of the maguey syrup (Agave salmiana and A. mapisaga) obtained through three treatments
During the Pre-Colombian period magueys were used in Mesoamerica for their sap, which is named “aguamiel” (literally “honey water” in Spanish). Aguamiel is then fermented into “pulque”, followed by (in order of importance): textiles, apparel, different thicknesses cords, food (sweetener, syrup, vinegar, flower buds, and cooked immature flowering stalks), firewood and construction materials. The maguey syrup is a product that is traditionally obtained by concentrating the aguamiel by means of an artisanal evaporation treatment (high temperatures, atmospheric pressure and prolonged times). The nutritional and nutraceutical value of this concentrate is unknown despite its wide consumption since pre-Hispanic times in various regions of Mexico. The objective of this work was to evaluate the nutritional value and the content of antioxidant compounds of the maguey syrup obtained from the aguamiel (Agave salmiana and A. mapisaga) through three elaboration treatments (artisanal evaporation, evaporation under reduced pressure and lyophilization). The best species for the production of maguey syrup turned out to be the aguamiel of the A. salmiana due to its nutritional and nutraceutical attributes, higher content of reducing sugars and lower sucrose compared to that of A. mapisaga. The maguey syrup is a sweetener with a higher content of protein (3320 mg 100-1) in comparison to bee honey (152.7 mg 100 g-1). The maguey syrup obtained by lyophilization (LYT) retained the nutraceutical value; but its antioxidant activity was statistically equal to the syrup obtained by evaporation under reduced pressure (RPT), and the artisanal evaporation treatment (AET) had a decrease in vitamin C content in comparison to LYT and RPT. The syrups obtained by RPT and AET presented different degrees of non-enzymatic darkening, possibly due to the formation of melanoidins (dark pigments). The darkest syrup obtained by AET had the highest antioxidant capacity (987.24 μM TE 100 g-1) associated to a higher content of phenolic compounds (593.74 mg GAE 100 g-1)
High Performance Technology in Algorithmic Cryptography
Alan Turing’s article, “Computation and intelligence”, gives the preamble of the characteristics of guessing if it is a machine or another human being. Currently, the use of ubiquitous technologies, such as the use of firmware, allows direct access to analog data, however, we must find a way to secure the information. Analyzing cryptographic algorithms for the transfer of multimedia information. Raise the use of cryptarithmetic. Finite automata will be developed that will govern the logic of the cryptographic algorithms to be integrated into Firmware, performance tests and controls will be carried out to determine the best strategies for their performance and algorithmic complexity. Technologies are expressed that allow the creation of learning environments, such as neural networks, that support other processes as the recognition of patterns on images
Optimizing the production of the biosurfactant lichenysin and its application in biofilm control
Aims: Apply response surface methodology (RSM) to develop and optimize an economical medium for lichenysin production, which is a surfactant produced by Bacillus licheniformis and evaluate the application of lichenysin in the prevention and disruption of pathogenic micro-organism biofilm that creates health problems in the food industry and hospitals. Results: An economical medium containing molasses was optimized to enhance lichenysin production by RSM. A production of 3.2 g l 1 of lichenysin was achieved with an optimum medium containing 107.82 g l 1 of molasses, 6.47 g l 1 of NaNO3 and 9.7 g l 1 of K2HPO4/KH2PO4, in which molasses and phosphate salts had a significant effect on biosurfactant production. Lichenysin was effectively applied in a surface pre-treatment to avoid microbial biofilm development of methicillin-resistant Staphylococcus aureus (MRSA) (68.73%) and Candida albicans (74.35%), with ED50 values of 8.3 and 17.2 lg ml 1 respectively. It was also very efficient in a surface posttreatment to remove biofilms of MRSA (55.74%) and Yersinia enterocolitica (51.51%), with an ED50 of 2.79 and 4.09 lg ml 1 respectively. Conclusions: Lichenysin was found to have notable anti-adhesion activity, being able to prevent and eliminate the biofilm formation by pathogenic strains associated with foodborne illness. This new medium resulted in a fourfold increase in production compared with the nonoptimized medium. Significance and Impact of the Study: Molasses can be regarded as a useful resource for biotechnological applications, such as the production of lichenysin. The use of agro-industrial substrates has an important role in the sustainable and competitive development of several industrial sectors, as well as in industrial residues management. Additionally, lichenysin is particularly effective in preventing biofilm formation by strains problematic for the food industry and in the hospital environment. Lichenysin also efficiently disrupts biofilm
Constraints on Finite Soft Supersymmetry-Breaking Terms
Requiring the soft supersymmetry-breaking (SSB) parameters in finite
gauge-Yukawa unified models to be finite up to and including two-loop order, we
derive a two-loop sum rule for the soft scalar-masses. It is shown that this
sum rule coincides with that of a certain class of string models in which the
massive string states are organized into N=4 supermultiplets. We investigate
the SSB sector of two finite SU(5) models. Using the sum rule which allows the
non-universality of the SSB terms and requiring that the lightest superparticle
particleis neutral, we constrain the parameter space of the SSB sector in each
model.Comment: 34 page
Nutritional Value and Sensory Properties of Cookies Prepared from Flour Mixes of Carrot (Daucus Carota), Lupine (Lupinus Perennis) and Barley (Hordeum Vulgare)
Nutritional value and sensory properties of cookies prepared by the combination of different proportions of carrot flour (CF), lupine flour (LF) and barley flour (BF) blends were analyzed. Eight formulations (F) of cookies were prepared from (F1) Control (100% Wheat flour “WF”), (F2) 33.33% CF, 33.33% LF and 33.33% BF, (F3) 33.33% CF, 41.66% LF and 25% BF, (F4) 33.33% CF, 25% LF and 41.66% BF, (F5) 33.33% CF, 25% LF and 41.66% BF, (F6) 41.66% CF, 33.33% LF and 25% BF, (F7) 25% CF, 41.66% LF and 33.33% BF, (F8) 41.66% CF, 25% LF and 33.33% BF. Cookies were subjected to analysis as moisture value, crude protein, Vitamin A as well as mineral analysis (potassium, calcium, phosphorus and iron) and evaluated for consumer acceptance by sensory analysis. Cookies prepared from formulation F8 showed high levels of vitamin A, (30UI/100 g), potassium (417.42 mg/100 g), calcium (182.40 mg/100 g) and iron (6.88 mg/100 g) in comparison with the others formulations. In the moisture value, F2 had similar value that the control cookies, The F3, F5 and F7 had high value in crude protein. Sensory evaluation established that cookies prepared with the formulation 8 were more acceptable than cookies prepared from other formulations
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