Production of pectinases by <i>A. niger</i>: Influence of fermentation conditions

Response surface methodology was used for optimization of polygalacturonase (PG) and pectinesterase (PE) production in submerged fermentation by A.niger. A Central Composite Experimental Design was applied, consisting of 22 experiments, including eight central points. Variables studied were: fermentation time (24 to 120 h), pH (3.5 to 6.5) and initial concentration of pectin (5 to 20 g/l). Maximum PE production was 220 U/l, after 74 h of culture, in a medium containing 20 g/l of pectin (pH 6.5). The optimal conditions for PG production were pH: 4.1, 20 g/l of pectin and 94 h of fermentation with a maximum value of 1032 U/l. Under these conditions, the PE production was low (15 U/l). A liquid extract with high PG activity and low PE activity could be suitable to be used in food processing in order to reduce the production of methanol.Facultad de Ciencias Exacta

iDistritos: Sectorización de modelos de redes hidráulicas de Epanet

[ES] La sectorización de una red de suministro de agua es una técnica muy utilizada para mejorar la eficiencia hidráulica del sistema (localización de fugas, gestión de la presión, etc.). Numerosas metodologías se han desarrollado para abordar este problema. Sin embargo, no todas se pueden aplicar a las necesidades particulares de cada sistema de suministro. Por ello se ha desarrollado una herramienta informática (iDistritos), basada en los algoritmos de búsqueda de la teoría de grafos y el simulador hidráulico de Epanet, para proponer e identificar sectores de demanda. La herramienta se ha aplicado en dos redes de agua potable reales en España y México.[EN] Water distribution network sectorization is a widely used technique to improve water system hydraulic efficiency (for leak location, pressure management, etc.). Several methodologies have been developed to address this problem. Not all of them can be applied to solve the particular needs of every supply system, however. Thus, a software tool (iDistricts) was developed, based on graph theory search algorithms and the Epanet hydraulic simulator, to propose and identify demand sectors. The tool has been applied two models of drinking water networks in Spain and Mexico.Vegas, O.; Martínez Alzamora, F.; Tzatchkov, V. (2021). iDistritos: Sectorización de modelos de redes hidráulicas de Epanet. Revista Hidrolatinoamericana de Jóvenes Investigadores y Profesionales. 5:13-15. http://hdl.handle.net/10251/1898981315

Relaciones entre indicadores de mineralización de nitrógeno y fracciones orgánicas en suelos del sudoeste bonaerense

En la actualidad, no existen estudios que establezcan relaciones de los indicadores de mineralizaci&oacute;n de nitr&oacute;geno (N)-como el N determinado en anaerobiosis (Nan) y el N hidrolizable (Nhid)- con las fracciones org&aacute;nicas en suelos con aportes variables de materia org&aacute;nica particulada (MOP). El objetivo de este estudio fue evaluar al Nan y Nhid, y la relaci&oacute;n con las fracciones org&aacute;nicas de carbono (C) y N del suelo, l&aacute;biles y recalcitrantes en suelos del sudoeste bonaerense (SOB). Durante 2010 y 2011, se muestrearon 78 lotes bajo siembra directa (SD)en 0-20 cm, destinados al cultivo de trigo (Triticum aestivum L.) y de cebada cervecera (Hordeum vulgare L.) dentro de lo que comprende la regi&oacute;n semi&aacute;rida y subh&uacute;meda. Se cuantifico Nhid y Nan, y se evalu&oacute;: carbono org&aacute;nico total (COT), particulado (COP) y asociado a la fracci&oacute;n mineral (COM); N org&aacute;nico total (Nt), particulado (NOP), y asociado a la fracci&oacute;n mineral (NOM), carbohidratos totales (CHt) y solubles (CHs). Los suelos se clasificaron en 2 grupos por el an&aacute;lisis de cl&uacute;ster de acuerdo a las fracciones org&aacute;nicas y al contenido de limo+arcilla: A y B. Los valores de Nhid y Nan fueron de 6,5-50,4 mg kg-1 y 10,7-81,9 mg kg-1, respectivamente. Se hallaron asociaciones significativas entre Nan y Nhid con las fracciones org&aacute;nicas evaluadas que difirieron seg&uacute;n el grupo de suelo considerado. Las relaciones entre Nan y Nhid con los diferentes pooles de C y N, l&aacute;biles o recalcitrantes, son dependientes de la protecci&oacute;n f&iacute;sica producida por el limo+arcilla. El an&aacute;lisis de cl&uacute;ster permiti&oacute; lograr este agrupamiento en base a varias fracciones org&aacute;nicas y deber&iacute;a ser usado para comparar suelos con condiciones similares

Genetic Characterization of Rubella Virus Strains Detected in Spain, 1998-2014

The National Plan for the Elimination of Rubella was implemented in Spain in 2008 using the logistics of the National Plan for the Elimination of Measles that have been employed since year 2000. Molecular characterization of rubella virus (RUBV) is important for disease surveillance and for monitoring elimination of the disease throughout the world. We describe the first complete series of data regarding the circulation of RUBV genotypes in Spain. The 739-nucleotide fragment designated by the WHO for RUBV genotyping was sequenced in 88 selected cases collected from 1998 to 2014. Five genotypes were identified: 1E, 2B, 1J, 1I, and 1a. Genotype 1E was predominant between 1998 and 2003 but was replaced by genotype 2B, which was detected in sporadic cases in 2004, 2006, 2008, 2012, 2013 and 2014. There was an outbreak of genotype 2B in Algeciras (Andalusia) in 2008. Genotype 1J caused an outbreak in Madrid in 2004/2005 and sporadic cases in 2005 and 2007. Genotype 1I was found to have infected an immune-suppressed patient with neurological symptoms in 2008. Finally, vaccine strain RA 27/3 was detected in three sporadic cases, two of them immune-suppressed and without a recent history of vaccination. This suggests that during these years there were a series of imported sporadic cases and outbreaks, confirming the findings of epidemiological data analysis. The importation sources were generally consistent with our geographic and cultural ties, mainly with Europe (genotypes 1E, 2B, 1I) and Latin America (1J)

Osteotomía valgizante de tibia: estudio de dos técnicas quirúrgicas

Se evalúan clínica y radiológicamente 51 rodillas artrósicas tratadas median - te osteotomía tibial valguizante según dos técnica s diferentes con fines comparativos. En 37 rodillas se empleó la osteotomía en cúpula con fijador externo y en las restante s se practicó la técnica en cuña de sustracción. El período de seguimiento medio fue de 42.2 meses. La suma de resultados buenos y excelente s ha sido 77.9%. La osteotomía en cúpula tiene , en esta serie, un mayor índice de pérdidas de corrección, correcciones insuficientes y complicaciones, obteniendo menor porcentaje de buenos resultados. Estos se deterioran en pacientes de mayor edad y gonartrosis evolucionada. Los autores consideran la osteotomía valguizante de tibia, un tratamiento válido par a pacientes de edad no avanzada y con gonartrosis grados I y II con genu varo.Two tecniques o f high tibia l osteotom y i n fifty-one ostheoarthiti c knee s evaluate d b y roentgenographi c an d clinica l examination . I n thirty-seve n patien s a dom e shape d osteotom y wit h externa l fixatio n wa s done . I n th e rest o f case s w e performe d a wedg e osteotomy . T h e numbe r o f goo d an d excelen t results wa s 77.9%. Th e dom e osteotom y ha s i n o u r experience , a hig h rat e o f recurren t varu s angulation , malalignemen t an d othe r complications. T h e olde r grou p o f patients ha d wors e results. Th e author s recomen d th e wedg e hig h tibia l osteotom y fo r osteoarthritis an d varu s kne e i n younge r patients

Surveying Safety-relevant AI Characteristics

[Otros] The current analysis in the AI safety literature usually combines a risk or safety issue (e.g., interruptibility) with a particular paradigm for an AI agent (e.g., reinforcement learning). However, there is currently no survey of safety-relevant characteristics of AI systems that may reveal neglected areas of research or suggest to developers what design choices they could make to avoid or minimise certain safety concerns. In this paper, we take a first step towards delivering such a survey, from two angles. The first features AI system characteristics that are already known to be relevant to safety concerns, including internal system characteristics, characteristics relating to the effect of the external environment on the system, and characteristics relating to the effect of the system on the target environment. The second presents a brief survey of a broad range of AI system characteristics that could prove relevant to safety research, including types of interaction, computation, integration, anticipation, supervision, modification, motivation and achievement. This survey enables further work in exploring system characteristics and design choices that affect safety concernsFMP and JHO were supported by the EU (FEDER) and the Spanish MINECO under grant TIN 2015-69175-C4-1-R, by Generalitat Valenciana (GVA) under grant PROME-TEOII/2015/013 and by the U.S. Air Force Office of Scientific Research under award number FA9550-17-1-0287. FMP was also supported by INCIBE (Ayudas para la excelencia de los equipos de investigacion avanzada en ciberseguridad), the European Commission, JRC¿s Centre for Advanced Studies, HUMAINT project (Expert Contract CT-EX2018D335821-101), and UPV PAID-06-18 Ref. SP20180210. JHO was supported by a Salvador de Madariaga grant (PRX17/00467) from the Spanish MECD for a research stay at the Leverhulme Centre for the Future of Intelligence (CFI), Cambridge, and a BEST grant (BEST/2017/045) from GVA for another research stay also at the CFI. JHO and SOH were supported by the Future of Life Institute (FLI) grant RFP2-152. SOH was also supported by the Leverhulme Trust Research Centre Grant RC2015-067 awarded to the Leverhulme Centre for the Future of Intelligence, and a a grant from Templeton World Charity FoundationHernández-Orallo, J.; Martínez-Plumed, F.; Avin, S.; Heigeartaigh, SO. (2019). Surveying Safety-relevant AI Characteristics. CEUR Workshop Proceedings. 1-9. http://hdl.handle.net/10251/146561S1

Production of pectinases by <i>A. niger</i>: Influence of fermentation conditions

Response surface methodology was used for optimization of polygalacturonase (PG) and pectinesterase (PE) production in submerged fermentation by A.niger. A Central Composite Experimental Design was applied, consisting of 22 experiments, including eight central points. Variables studied were: fermentation time (24 to 120 h), pH (3.5 to 6.5) and initial concentration of pectin (5 to 20 g/l). Maximum PE production was 220 U/l, after 74 h of culture, in a medium containing 20 g/l of pectin (pH 6.5). The optimal conditions for PG production were pH: 4.1, 20 g/l of pectin and 94 h of fermentation with a maximum value of 1032 U/l. Under these conditions, the PE production was low (15 U/l). A liquid extract with high PG activity and low PE activity could be suitable to be used in food processing in order to reduce the production of methanol.Facultad de Ciencias Exacta

Hypersaline Infusion Protocol through the Portal Vein may Focus Electroporation on Tumor Tissue, but is it really Safe? Preliminary Results

Introduction: Irreversible Electroporation (IRE) is highly dependent on the electrical conductivity of the tissue and the high conductivity of tumor tissue, which leads to a lower field than in the surrounding healthy tissue. Hypersaline Infusion (HI) through the portal vein focuses IRE on scattered liver tumors, by creating a differential conductivity between the different types of tissue. The aim of this study is to determine the effects of the HI protocol on the hepatic and histological biochemical results. Methods: Ten male Sprague Dawley rats were used for HI protocol. Blood samples were collected at pre-, immediately post-, 24-hrs, 72-hrs, 1-week and 3-weeks post-HI. All the animals were sacrificed after one-month follow-up in order to collect histological samples. Results: The mortality rate in this procedure reached 30% (3/10). Only the pH and transaminases at 24-hrs were significantly and directly linked to mortality (p=0.036 and p=0.004, respectively). The three non-surviving animals had a four-time higher AST level at 24-hrs. Natremia normalized at 24-hrs post-HI. Statistically significant differences were found in hepatic necrosis between the non-surviving (n=3) and surviving rats (n=7) (30.67 ± 10.97 vs. 2.86 ± 7.56% respectively, p=0.01). Discussion: HI through the portal system involves a significant risk of possibly lethal cytolysis and acidosis. Therefore, compensatory measures and a reduced saline overload are warranted to improve the survival rates

Modeling the flux of metabolites in the juvenile hormone biosynthesis pathway using generalized additive models and ordinary differential equations

Juvenile hormone (JH) regulates development and reproductive maturation in insects. The corpora allata (CA) from female adult mosquitoes synthesize fluctuating levels of JH, which have been linked to the ovarian development and are influenced by nutritional signals. The rate of JH biosynthesis is controlled by the rate of flux of isoprenoids in the pathway, which is the outcome of a complex interplay of changes in precursor pools and enzyme levels. A comprehensive study of the changes in enzymatic activities and precursor pool sizes have been previously reported for the mosquito Aedes aegypti JH biosynthesis pathway. In the present studies, we used two different quantitative approaches to describe and predict how changes in the individual metabolic reactions in the pathway affect JH synthesis. First, we constructed generalized additive models (GAMs) that described the association between changes in specific metabolite concentrations with changes in enzymatic activities and substrate concentrations. Changes in substrate concentrations explained 50% or more of the model deviances in 7 of the 13 metabolic steps analyzed. Addition of information on enzymatic activities almost always improved the fitness of GAMs built solely based on substrate concentrations. GAMs were validated using experimental data that were not included when the model was built. In addition, a system of ordinary differential equations (ODE) was developed to describe the instantaneous changes in metabolites as a function of the levels of enzymatic catalytic activities. The results demonstrated the ability of the models to predict changes in the flux of metabolites in the JH pathway, and can be used in the future to design and validate experimental manipulations of JH synthesis.Facultad de Ciencias ExactasCentro Regional de Estudios Genómico

Comparison of an increased waist circumference with a positive hydrogen breath test as a clinical predictor of lactose intolerance

ABSTRACT Introduction. Lactose intolerance is a common disease in pediatrics, and its wrong diagnosis will lead to morbidity. The primary objective of this study was to assess the usefulness of an increased waist circumference during the hydrogen breath test as a predictor of lactose intolerance. The secondary objective was to analyze the impact of body mass index, waist circumference measurement, and age on the abdominal distension of patients with lactose intolerance. Population and methods. A total of 138 subjects aged 3 to 15 years were included. They underwent serial measurements of the waist circumference and hydrogen levels in the breath every 30 minutes over 3 hours during the hydrogen breath test. Results. Out of the entire sample, 35 (25.4%) patients had lactose intolerance. An increase of 0.85 cm in waist circumference compared to the baseline waist circumference results in a sensitivity of 88% and a specificity of 85% to predict lactose intolerance (odds ratio: 42.14, 95% confidence interval: 13.08-135.75, p ≤ 0.001). The body mass index and waist circumference measurement did not affect abdominal distension (p= not significant); however, age modified the time of distension. Conclusions. A 0.85 cm increase in waist circumference compared to the baseline waist circumference during the hydrogen breath test is a useful parameter for the diagnosis of lactose intolerance in pediatrics. Variations in relation to body mass index and waist circumference did not affect the usefulness of an increased waist circumference, unlike age. Key words: lactose intolerance, waist circumference, diagnosis, exhaled hydrogen breath, child