Coacervación compleja entre la goma arábiga y el quitosano: aplicación potencial en emulsiones y microencapsulados

de aceite de canola como fase oleosa empleando goma arábiga como emulsionante. Las emulsiones de mayor estabilidad fueron producidas empleando 7600 rpm y 10 % (p/p) de goma arábiga. La emulsión simple con quitosano mostró una menor estabilidad en comparación con las emulsiones de goma arábiga. Tomando en cuenta esto, la formación de una emulsión simple por coacervación se efectuó mediante la adsorción secuencial de os biopolímeros a la interfase. Primero se formuló la emulsión simple con goma arábiga al 10% (p/p) y, posteriormente, esta emulsión fue redispersada en una solución de quitosano al 2% (p/p ), produciendo la emulsión por coacervación O/W GAQ· El incremento de la fase dispersa en las emulsiones O/ W GAQ originó un incremento en las propiedades viscoelásticas de las emulsiones. Las emulsiones O/W GAQ con un contenido de fase dispersa del 1 O y 20% (p/p) presentaron un comportamiento viscoso en todo el intervalo de frecuencias, estas dos emulsiones pueden ser utilizadas en aplicaciones de secado por aspersión. La emulsión O/WaAQ con un contenido de fase dispersa del 40% (p/p) presentó un comportamiento elástico en todo el intervalo de frecuencias. Las emulsiones O/W GA y O/WaAQ, ambas con un contenido de fase dispersa del 20% (p/p ), fueron secadas por aspersión bajo las mismas condiciones para obtener los respectivos sistemas microencapsulados. Ambos sistemas presentaron la formación de microencapsulados esferoidales que contenían en su inte rior pequeñas microcápsulas. Los microencapsulados producidos a partir de la emulsión por coacervación O/WaAQ mostraron una mayor unifonnidad de tamaño, con menor área superficial, y mayor densidad del material de barrera en comparación con los microencapsulados de goma arábiga.En este trabajo se investigó la formación de complejos poliméricos entre la goma arábiga (GA) y el quitosano (Q), dos polisacáridos de carga opuesta, como una función de la relación de biopolímeros, concentración total de biopolímeros, pH y concentración de NaCI. Se determinaron las condiciones de formación de los complejos interbiopoliméricos insolubles ( coacervación compleja) usando mediciones potenciométricas de los biopolímeros en solución; turbidimétricas y movilidad electroforética de la fase en equilibrio; y rendimiento de la fase coacervada. Las concentraciones relativas de los biopolímeros en la fa se coacervada y la fase en equilibrio fueron cuantificadas por análisis elemental y cromatografía de líquidos de alta resolución, respectivamente. Los resultados indican que el mayor rendimiento de coacervado se obtiene al mezclar 5 gramos de goma arábiga por gramo de quitosano, independientemente de la concentración total de biopolímero usada. La formación de los complejos goma arábiga-quitosano dependen del pH y concentración de sal. El intervalo de pH de máxima interacción fu e ubicado entre 3.5 - 5, con un punto de resistencia de NaCl de 150 mM. Los espectros de infrarrojo indicaron que el acomplejamiento se llevan a cabo por la interacción de los grupos carb_oxilo de la goma arábiga y los grupos amino del quitosano Los complejos insolubles goma arábiga-quitosano fueron caracterizados como geles débiles con carácter predominantemente viscoso característico de las matrices coacervadas, presentando mayores propiedades viscoelásticas a un pH = 4.5. Las micrografías de los complejos goma arábiga-quitosano muestran un alto grado de entrecruzamiento entre los biopolímeros y presentan estructuras intrincadas de un gel complejo. Poste1iormente, se evaluaron las condiciones de formulación d

Gelatin–chitosan–PVA hydrogels and their application in agriculture

This work demonstrated the ability of a fabrication process in the preparation of gelatin-chitosan-PVA hydrogels for potential agricultural applications. The hydrogels showed a dense, tridimensional, interconnected and reticulated structure that was more evident in the hydrogel loaded with inulin. The hydrogels showed a water absorption capacity of ≤12 times its mass. FTIR and light microscopy demonstrated that the hydrogels were biodegradable. The percentage of degradation of hydrogels in inoculated soil was higher than in sterile soil using the soil burial test. Hydrogel loaded with inulin was found to be capable of inducing resistance in chili plants against Phytophthora capsici.ITESO, A.C

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Measurement of prompt open-charm production cross sections in proton-proton collisions at root s=13 TeV

The production cross sections for prompt open-charm mesons in proton-proton collisions at a center-of-mass energy of 13TeV are reported. The measurement is performed using a data sample collected by the CMS experiment corresponding to an integrated luminosity of 29 nb(-1). The differential production cross sections of the D*(+/-), D-+/-, and D-0 ((D) over bar (0)) mesons are presented in ranges of transverse momentum and pseudorapidity 4 < p(T) < 100 GeV and vertical bar eta vertical bar < 2.1, respectively. The results are compared to several theoretical calculations and to previous measurements.Peer reviewe

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

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Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Development and validation of HERWIG 7 tunes from CMS underlying-event measurements

This paper presents new sets of parameters (“tunes”) for the underlying-event model of the HERWIG7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in HERWIG7, and are obtained from a fit to minimum-bias data collected by the CMS experiment at s=0.9, 7, and 13Te. The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the dat

Reconstruction of signal amplitudes in the CMS electromagnetic calorimeter in the presence of overlapping proton-proton interactions

A template fitting technique for reconstructing the amplitude of signals produced by the lead tungstate crystals of the CMS electromagnetic calorimeter is described. This novel approach is designed to suppress the contribution to the signal of the increased number of out-of-time interactions per beam crossing following the reduction of the accelerator bunch spacing from 50 to 25 ns at the start of Run 2 of the LHC. Execution of the algorithm is sufficiently fast for it to be employed in the CMS high-level trigger. It is also used in the offline event reconstruction. Results obtained from simulations and from Run 2 collision data (2015-2018) demonstrate a substantial improvement in the energy resolution of the calorimeter over a range of energies extending from a few GeV to several tens of GeV.Peer reviewe