The Trigonometric Rosen-Morse Potential in the Supersymmetric Quantum Mechanics and its Exact Solutions

The analytic solutions of the one-dimensional Schroedinger equation for the trigonometric Rosen-Morse potential reported in the literature rely upon the Jacobi polynomials with complex indices and complex arguments. We first draw attention to the fact that the complex Jacobi polynomials have non-trivial orthogonality properties which make them uncomfortable for physics applications. Instead we here solve above equation in terms of real orthogonal polynomials. The new solutions are used in the construction of the quantum-mechanic superpotential.Comment: 16 pages 7 figures 1 tabl

Postharvest shelf life extension of blueberries using a chitosan-based edible coating containing aloe vera juice

PosterBlueberries are currently one of the most valuable fruits worldwide, due to their organoleptic and nutritional properties. However these fruits are highly perishable due to their susceptibility to fungal infections (e.g. Botrytis cinerea) and water loss during storage. Edible coatings can improve fruits quality and extend their shelf life by providing a barrier to moisture and gases. The incorporation of natural antifungal compounds, e.g. Aloe vera, into edible coatings provides a novel way to enhance edible coatings properties without using synthetic compounds. In this study, chitosan-based coating (0.5% (w/v)) incorporating Aloe vera juice (0.5% (w/v)) was applied to blueberries to evaluate: (1) their antifungal efficiency and (2) postharvest quality of cold-stored blueberries. Uncoated (B) and coated blueberry (BC) samples were monitored over 25 days at 5.5±0.6 °C and 90±3 % relative humidity. During storage time, samples were analyzed in terms of weight loss, microbiological growth, titratable acidity, pH, soluble solids content, and color properties. Results showed that BC treatment delayed blueberries dehydration after 25 days, since B and BC samples weight losses were 6.2% and 3.7%, respectively. B samples presented contamination after 2 days of storage (2.0 log CFU/g), whilst BC samples presented mold contamination only after 9 days of storage (1.3 log CFU/g). The pH of BC samples remained lower (3.15) than that of B samples (3.54) after 12 days of storage. During storage, B samples had significantly lower titratable acidity values than BC samples (p<0.05), demonstrating that the coating helped retaining acidity of blueberries. Chitosan-based coatings with Aloe vera demonstrated great potential in extending blueberries shelf-life (about 5 days). Moreover, two main factors of blueberry postharvest deterioration (microbiological growth and water loss levels) were reduced, which may represent a significant commercial value to blueberries producers

Effect of chitosan-Aloe vera coating on postharvest quality of blueberry (Vaccinium corymbosum) fruit

The present study was carried out to evaluate the effect of chitosan-based edible coatings with Aloe vera extract on the postharvest blueberry fruit quality during storage at 5 °C. Firstly, A. vera fractions (pulp and liquid) were extracted from leaves and evaluated in terms of antifungal and antioxidant capacities. The choice of the most adequate chitosan and A. vera fraction concentrations to be incorporated in coating formulation was made based on the wettability of the corresponding coating solutions. Coatings with 0.5% (w/v) chitosan + 0.5% (w/v) glycerol + 0.1% (w/v) Tween 80 + 0.5% (v/v) A. vera liquid fraction presented the best characteristics to uniformly coat blueberry surface. Physico-chemical (i.e., titratable acidity, pH, weight loss) and microbiological analyses of coated blueberries (non-inoculated or artificially inoculated with Botrytis cinerea) were performed during 25 d. Microbiological growth and water loss levels were approximately reduced by 50% and 42%, respectively, in coated blueberries after 25 d compared to uncoated blueberries. After 15 d, weight loss values were 6.2% and 3.7% for uncoated and chitosanA. vera coated blueberries, respectively. Uncoated fruits presented mold contamination after 2 d of storage (2.0 ± 0.32 log CFU g1), whilst fruits with chitosan-based coatings with A. vera presented mold contamination only after 9 d of storage (1.3 ± 0.35 log CFU g1). Overall, coatings developed in this study extend blueberries shelf-life for about 5 d, demonstrating for the first time that the combination of chitosan and A. vera liquid fraction as edible coating materials has great potential in expanding the shelf-life of fruits.Joana T. Martins (SFRH/BPD/89992/2012) is the recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, Portugal). María L. Flores-López thanks Mexican Science and Technology Council(CONACYT, Mexico) for PhD fellowship support (CONACYT Grant number: 215499/310847). The authors thank the FCT the strategic funding of UID/BIO/04469/2013 unit and the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER- 027462)

Deletion of GPIHBP1 causing severe chylomicronemia

Lipoprotein lipase (LPL) is a hydrolase that cleaves circulating triglycerides to release fatty acids to the surrounding tissues. The enzyme is synthesized in parenchymal cells and is transported to its site of action on the capillary endothelium by glycophosphatidylinositol (GPI)-anchored high-density lipoprotein-binding protein 1 (GPIHBP1). Inactivating mutations in LPL; in its cofactor, apolipoprotein (Apo) C2; or in GPIHBP1 cause severe hypertriglyceridemia. Here we describe an individual with complete deficiency of GPIHBP1. The proband was an Asian Indian boy who had severe chylomicronemia at 2 months of age. Array-based copy-number analysis of his genomic DNA revealed homozygosity for a 17.5-kb deletion that included GPIHBP1. A 44-year-old aunt with a history of hypertriglyceridemia and pancreatitis was also homozygous for the deletion. A bolus of intravenously administered heparin caused a rapid increase in circulating LPL and decreased plasma triglyceride levels in control individuals but not in two GPIHBP1-deficient patients. Thus, short-term treatment with heparin failed to attenuate the hypertriglyceridemia in patients with GPIHBP1 deficiency. The increasing resolution of copy number microarrays and their widespread adoption for routine cytogenetic analysis is likely to reveal a greater role for submicroscopic deletions in Mendelian conditions. We describe the first neonate with complete GPIHBP1 deficiency due to homozygosity for a deletion of GPIHBP1

Fructosyltransferase Sources, Production, and Applications for Prebiotics Production

Fructooligosaccharides (FOS) are considered prebiotic compounds and are found in different vegetables and fruits but at low concentrations. FOS are produced by enzymatic transformation of sucrose using fructosyltransferase (FTase). Development of new production methods and search for FTase with high activity and stability for FOS production Is an actual research topic. In this article is discussed the most recent advances on FTase and its applications. Different microorganisms have been tested under various fermentation systems in order to identify and characterize new genes codifying for FTase. Some of these genes have been isolated from bacteria, fungi, and plants, with a wide range of percentages of identity but retaining the eight highly conserved motifs of the hydrolase family 32 glycoside. Therefore, this article presents an overview of the most recent advances on FTase and its applications

Bioreactor design for enzymatic hydrolysis of biomass under the biorefinery concept

The dependence on non-renewable resources, particularly fossil fuels, has awaken a growing interest in research of sustainable alternative energy sources, such as bioethanol. The production of bioethanol from lignocellulosic materials comprises three main stages, starting with a pretreatment, followed by an enzymatic hydrolysis step where fermentable sugars are obtained for the final fermentation process. Enzymatic hydrolysis represents an essential step in the bioethanol production, however there are some limitations in it that hinders the process to be economically feasible. Different strategies have been studied to overcome these limitations, including the enzyme recycling and the utilization of high solids concentrations. Several investigations have been carried out in different bioreactor configurations with the aim to obtain higher yields of glucose in the enzymatic hydrolysis stage; however, the commonest are Stirred Tank Bioreactors (STBR) and Membrane Bioreactors (MBR). In general, the key criteria for a bioreactor design include adequate mass transfer, low shear stress, and efficient mixing that allows the appropriated interaction between the substrate and the enzyme. Therefore, this review will address the main aspects to be considered for a bioreactor design, as well as, the operational conditions, some characteristics and mode of operating strategies of the two main bioreactors used in the enzymatic hydrolysis stage. Moreover, two types of pneumatically agitated bioreactors, namely bubble column and gas-lift bioreactors, are discussed as promising alternatives to develop enzymatic saccharification due to their low energy consumption compared with STBR.This work was financial supported by the Secretary of Public Education of Mexico – Mexican Science and Technology Council (SEPCONACYT) with the Basic Science Project-2015-01 (Ref. 254808), and the Energy Sustainability Fund 2014-05 (CONACYT-SENER), Mexican Centre for Innovation in Bioenergy (Cemie-Bio), and Cluster of Bioalcohols (Ref. 249564). The author Marcela Pino also thanks the National Council for Science and Technology (CONACYT, Mexico) for her Master Fellowship support (grant number: 611312/452636).info:eu-repo/semantics/publishedVersio

Production of an Enzymatic Extract From Aspergillus oryzae DIA-MF to Improve the Fructooligosaccharides Profile of Aguamiel

Aguamiel is a natural sap produced by some species of agave plants, such as Agave salmiana, A. atrovirens, or A. angustifolia. It is a product with a high concentration of fructose, glucose or sucrose, although its composition may vary depending on the season in which it is produced, and may also contain agave fructans (or agavins) or fructooligosaccharides (FOS). It has been reported that FOS can be produced by enzymes that act on sucrose or inulin, transfructosylating or hydrolyzing these materials, respectively. Due to the sugar content in aguamiel, the application of an enzymatic complex produced by Aspergillus oryzae DIA MF was carried out. This complex was characterized by 1-D electrophoresis SDS-PAGE, and its transfructosylation and hydrolysis activities were determined by HPLC. In order to determine the conditions at which the concentration of FOS in this beverage increased, kinetics were carried out at different temperatures (30, 50, and 70°C) and times (0, 1, 2, 3, 4, 5, 10, and 15 h). Finally, the antioxidant and prebiotic activities were evaluated. FOS concentration in aguamiel was increased from 1.61 ± 0.08 to 31.01 ± 3.42 g/ L after 10 h reaction at 30°C applying 10% enzymatic fraction-substrate (v/v). Antioxidant activity was highly increased (34.81–116.46 mg/eq Trolox in DPPH assay and 42.65 to 298.86 mg/eq Trolox in FRAP assay) and growth of probiotic bacteria was higher in aguamiel after the enzymatic treatment. In conclusion, after the application of the enzymatic treatment, aguamiel was enriched with FOS which improved antioxidant and prebiotic properties, so it can be used as a functional food

Simulador para un yacimiento de gas basado en una solución numérica explícita

En este trabajo se presenta las ecuaciones fundamentales para desarrollar un simulador de yacimiento de gas acoplado a un pozo productor. El simulador se construye utilizando la ecuación gobernante para el pozo en estado estacionario, la cual está acoplada a la ecuación de flujo del yacimiento escrita en forma explícita. La ecuación del pozo se resuelve numéricamente utilizando un esquema de diferencias finitas hacia adelante, mientras que se usa un esquema iterativo para la ecuación explícita del yacimiento con el fin de encontrar la presión en cada bloque numérico a cada paso de tiempo. El simulador depende del tamaño del paso de tiempo para obtener soluciones numéricas estables y consistentes, por lo que el número de bloques para discretizar el yacimiento es reducido. A pesar de esta restricción, el simulador es de utilidad para estimar reservas y el influjo al pozo, realizar la interpretación de pruebas de presión y análisis nodal, etc. El simulador se aplicó en un caso base, donde se determinó las presiones a lo largo del pozo, en fondo de pozo, y en el yacimiento