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Spent coffee grounds (SCGs) are a good source of chlorogenic acid (CGA), which can be hydrolyzed to quinic acid (QA) and caffeic acid (CA). These molecules have antioxidant and neuroprotective capacities, benefiting human health. The hydrolysis of CGA can be done by biotechnological processes, such as solid-state fermentation (SSF). This work evaluated the use of SSF with Aspergillus sp. for the joint release of the three molecules from SCGs.Hydroalcoholic extraction of the total phenolic compounds (TPCs) from SCGs was optimized, obtaining 28.9 ± 1.97 g gallic acid equivalent (GAE) kgSSF represents an alternative to produce extracts with different compositions and, consequently, different antioxidant capacities, which is a potentially attractive fermentation process for different applications. © 2022 Society of Chemical Industry.

La cardiomiopatía cirrótica se trata de una complicación en el paciente cirrótico, con una prevalencia superior al 40%. Es una entidad subclínica, pero ante el ejercicio o estrés circulatorio, desencadena su sintomatología. Su fisiopatología se explica por la hipertensión portal que lleva a vasodilatación esplácnica, con posterior liberación de vasodilatadores y factores cardiosupresores, lo cual conduce a una circulación hiperdinámica y disfunción circulatoria, con elevación del gasto cardíaco, disminución de la resistencia vascular y presión arterial baja. Sus características principales son disfunción cardiaca sistólica y diastólica, circulación hiperdinámica y alteraciones electrofisiológicas, especialmente prolongación del intervalo QT. Para su diagnóstico se usa la ecocardiografía y pruebas de estrés físico o farmacológico. No existe un protocolo de tratamiento estandarizado, sin embargo, el trasplante hepático puede ser un procedimiento efectivo para revertir la disfunción cardiaca en algunos pacientes. En el presente artículo se describen tanto las características de la cardiomiopatía cirrótica, como su papel en la morbilidad y mortalidad del paciente con cirrosis.

Introducción: la desnutrición es un estado de deficiencia de nutrientes esenciales o mala asimilación de los alimentos; es la principal causa de retardo de crecimiento y desarrollo, y de infecciones a edades tempranas. Se presenta un caso clínico cuyo diagnóstico tardío permitió analizar el contexto clínico y social. Caso clínico: varón de 8 meses con antecedente de anemia y ablactación temprana, 45 días antes del ingreso presenta placas marrones liquenificadas descamativas, alternadas con parches hipopigmentados de localización toracoabdominal, inguinogenital y en extremidades; además edema facial y de miembros inferiores; peso y talla baja, irritabilidad y temperatura de 38°C. El laboratorio reportó hipoproteinemia, anemia y leucopenia; se diagnostica desnutrición crónica severa proteico-calórica complicada con infección estafilocócica de piel y retraso del desarrollo. Se trató en hospitalización con antibioticoterapia, reposición electrolítica y plan de alimentación con fórmula, el paciente evolucionó favorablemente. Conclusión: el diagnóstico tardío de kwashiorkor representa un problema multifactorial de orden clínico y social, paciente ingresó al servicio febril con lesiones dérmicas importantes, edema, irritabilidad e hipertermia, retraso en el crecimiento; es tratado con antibióticos, hidratación y alimentación con fórmula; el paciente mejora y es dado de alta.

ResumenLa enfermedad metastásica vertebral es frecuente en los pacientes con cáncer avanzado, y conlleva a complicaciones inherentes a su progresión, como lo son la fractura patológica vertebral y la compresión neural metastásica. Se realizó una revisión de los aspectos terapéuticos actuales del manejo de la progresión y de las complicaciones de la enfermedad metastásica vertebral, enfatizando su enfrentamiento sistémico y personalizado. Nuestro objetivo principal es proporcionar información sobre el tratamiento actual de esta afección y la utilidad del manejo sistémico y multidisciplinario.

In the last decades, the production of value-added products from lignocellulosic biomass (LCB) has gained relevance. Xylans, which are the main hemicellulose compounds in LCB, may be extracted by alkaline pretreatment and employed for xylooligosaccharide (XOS) production. However, xylan extraction currently works as a black box due to the lack of characterization of the involved streams. Therefore, the appropriate operational conditions often remain unclear, especially in hardwoods. In this study, alkaline/thermal pretreatments at different operational conditions were evaluated for xylan extractions from Chilean Nothofagus species sawdust, determining the chemical compositions of the fractions at each step of the process. Results indicated that increasing alkali concentration (NaOH) leads to a higher xylan extraction, but also to high salt production during the acid neutralization step, decreasing xylan's purity and therefore XOS production. In this context, decreasing NaOH concentration and neutralizing it by membrane filtration, allow extracting xylans (62.5 %) of higher-purity (77 %).

The intensification of processes is essential for the sustainability of the biorefinery concept. Enzyme catalysis assisted by ultrasound (US) may offer interesting opportunities in the agri-food sector because the cavitation effect provided by this technology has been shown to improve the efficiency of the biocatalysts. This review presents the recent advances in this field, focused on three main applications: ultrasound-assisted enzymatic extractions (UAEE), US hydrolysis reactions, and synthesis reactions assisted by US for the manufacturing of agri-food produce and ingredients, enabling the upgrading of agro-industrial waste. Some theoretical and experimental aspects of US that must be considered are also reviewed. Ultrasonic intensity (UI) is the main parameter affecting the catalytic activity of enzymes, but a lack of standardization for its quantification makes it unsuitable to properly compare results. Applications of enzyme catalysis assisted by US in agri-foods have been mostly concentrated in UAEE of bioactive compounds. In second place, US hydrolysis reactions have been applied for juice and beverage manufacturing, with some interesting applications for producing bioactive peptides. In last place, a few efforts have been performed regarding synthesis reactions, mainly through trans and esterification to produce structured lipids and sugar esters, while incipient applications for the synthesis of oligosaccharides show promising results. In most cases, US has improved the reaction yield, but much information is lacking on how different sonication conditions affect kinetic parameters. Future research should be performed under a multidisciplinary approach for better comprehension of a very complex phenomenon that occurs in very short time periods.

Problema: Los proyectos formativos se basan en contenidos sin aplicación práctica y no logran un aprendizaje acorde con los retos del contexto social y profesional. Propósito: Mejorar los proyectos formativos para lograr una formación más pertinente, acorde con los retos del contexto social y profesional. Metodología: Investigación acción formativa o educativa en la propia práctica docente aplicada a 60 estudiantes del taller de proyectos arquitectónicos. Principales resultados: Planteamiento de mejora para el proyecto formativo Taller de Proyectos Arquitectónicos. Conclusión: Se ha mejorado el proyecto formativo, incorporando características del desarrollo social sostenible.

Galacto-oligosaccharides (GOS) are short oligosaccharides chains containing several galactoses and one terminal glucose. Raw GOS are mixtures containing oligosaccharides, unreacted lactose and monosaccharides; hence nanofiltration is an alternative for product purification. However, poor membrane selectivity towards separation of lactose from GOS is the main drawback. So, in order to improve the purification of enzymatically-produced GOS by nanofiltration, the incorporation of a previous lactose hydrolysis step, to convert the remaining lactose into monosaccharides, is proposed. The purification of raw and hydrolyzed raw GOS was evaluated using two nanofiltration polymeric membranes (Synder NFG and TriSep XN45) at different transmembrane pressures (8–30 bar) in a stirred dead-end cell. Results indicate that the incorporation of the lactose hydrolysis step allows increasing GOS retention and monosaccharides and lactose removal, improving GOS purification. Best operational conditions for hydrolyzed raw GOS nanofiltration were obtained with the TriSep XN45 membrane at 20 bar, 45 °C and 1500 rpm.

Limiting flux (JL) determination is a critical issue for membrane processing. This work presents a modified exponential model for JL calculation, based on a previously published version. Our research focused on skim milk microfiltrations. The processing variables studied were the crossflow velocity (CFV), membrane hydraulic diameter (dh), temperature, and concentration factor, totaling 62 experimental runs. Results showed that, by adding a new parameter called minimum transmembrane pressure, the modified model not only improved the fit of the experimental data compared to the former version (R2 &gt, 97.00%), but also revealed the existence of a minimum transmembrane pressure required to obtain flux (J). This result is observed as a small shift to the right on J versus transmembrane pressure curves, and this shift increases with the flow velocity. This fact was reported in other investigations, but so far has gone uninvestigated. The JL predicted values were correlated with the Reynolds number (Re) for each dh tested. Results showed that for a same Re, JL increased as dh decreased, in a wide range of Re within the turbulent regime. Finally, from dimensionless correlations, a unique expression JL = f (Re, dh) was obtained, predicting satisfactorily JL (R2 = 84.11%) for the whole set of experiments

La ley 1616 de 2013 de Colombia define a la salud mental como “un estado dinamico que se expresa en la vida cotidiana a traves del comportamiento y la interaccion”, y que permite utilizar los recursos emocionales, cognitivos y mentales de los individuos y de los grupos humanos, para vivir su cotidianidad de la manera mas adaptativa posible. Por su parte, la Organizacion Mundial de la Salud (OMS, 2001) define la salud mental como ese estado de bienestar que permite al individuo ser consciente de sus capacidades y afrontar las tensiones normales, trabajar productivamente y ser capaz de contribuir a su comunidad. La salud mental es mucho mas que la ausencia de trastornos mentales, es la capacidad de adaptarse al contexto, de manera que el individuo se sienta bien consigo mismo, a pesar de las circunstancias ambientales, sociales y/o socioeconomicas.

Variations in the quality of clarified apple juices subjected to a lab-scale concentration process were assessed. The processing conditions were similar to those used in an industrial three-effects evaporator: 85°C for 25 minutes during the first effect (E1), 75°C for 13 minutes during the second effect (E2) and 58°C for 20 minutes for the third effect (E3). The following parameters were measured at different times from samples of the three effects: Brix content, absorbance spectrum (200 to 670 nm), processing temperature, viscosity, pH, activity of water (Aw) and 5-hydroxymethylfurfural (HMF) concentration (measured via HPLC). The highest increase in HMF occurred during E3, reaching a concentration of 22.26 ± 1.32 mg/kg, with a Brix content of 65.93 ± 0.95. Such HMF concentrations were just below the European Food Regulation Standards. An increase of HMF correlated well with a decrease of Aw and pH. Absorbance spectral values within the UV range increased with increasing processing time, reflecting the non-enzymatic browning effect. Additionally, at measurements above 50° Brix, the effect of temperature and the Brix content had a significant effect on the viscosity. Partial least squares (PLS) regression and pre-processing data under an Orthogonal signal correction OSC + Wavelets (DWT) scenario yielded a multivariate calibration model that accurately predicted the appearance of HMF during the concentration process (R2 0.947). The proposed methodology may serve as an early warning against a critical threshold of HMF by offering a simple and fast physic-chemical analysis conventionally measured by most of the juice processing industry.

Pesticide soil sorption is a primary factor that influences the fate of pesticides in the environment, affecting regulation of microbiological and chemical degradation, volatilization and leaching. The main goal of this research was to study the effect of the organic phase of volcanic soils on sorption of agricultural pesticides. Sorption and desorption of eight agricultural pesticides were studied on eight volcanic soils that varied in the fulvic and humic constituents of their organic matter. For all pesticides, sorption was well described by a Freundlich isotherm where 1/nads values indicated that the sorption mechanism could be mainly explained by physical reactions in all soils. Kf values for carbaryl and flumioxazin were the highest with average values of 7.78 and 7.16 mL g-1, respectively. By contrast, hexazinone and metsulfuron-methyl had the lowest average Kf: 0.86 and 0.81 mL g-1, respectively, indicating that they were the least attracted to the soils. The organic fraction of the soil was the main soil factor related to the sorption of all study pesticides. Particularly, humic acid content regulated the sorption between pesticide and soil, especially through the carboxylic groups.

A convective drying process was optimized as strategy to produce dehydrated ingredients with high antioxidant capacity; using Hass avocado byproducts (peels and seeds). Studied processing variables were: temperature (45 °C–75 °C), air-flow (0.8 m/s to 1.8 m/s) and loading density (1 kg/m2 to 3 kg/m2). The response variables were Total Phenol Content (TPC) and Antioxidant Capacity (DPPH). Drying kinetic analysis revealed that seeds had higher water diffusivity than peels, but the latter showed shorter drying times. Multiple optimization routines allowed maximizing simultaneously DPPH and TPC. Thus, 62.82% and 54.81% of the initial TPC was retained in dehydrated peels and seeds, respectively. Sorption isotherms for both dehydrated byproducts showed that avocado seeds were more hygroscopic than peels, which was attributed to differences on their composition. This research has outlined a useful tool for the transformation of avocado wastes into storable commodities with high antioxidant properties which may have different food uses.

Accidents during elderly are one of the greatest geriatric syndromes due to the frequency with which they appear between patients. There are incidents that mark a milestone for acute and chronic deterioration in the health during old age. Among the instruments explored over time by the medical area in order to know the factors that lead to falls in elderly people, the Tinetti test is the most complete and validated measurement instrument. Tinetti is an observational scale that allows the evaluation by means of two sub-scales (i) the march (9 items) and (ii) the balance (13 items) in static position and when the patient is moving. Generally, this test is performed by specialized medical personnel (doctors or physiotherapists) and the acquisition of data used in each one of the items in this test is recorded manually. This paper presents the design and construction of an Assistive Technology Device, which supports medical personnel during the application of the balance sub-scale in the Tinetti test. This solution will consist of a carpet equipped with sensors that allows to know the position of the patient through heat maps and the body weight that is distributed in each area during the performance of the Tinetti test. In addition, it will allow the acquisition of data in a digital form, and since it is an object of the Internet of Things, it will allow the monitoring of the information coming from the test locally and remotely, as well as registering the information and making it available on the cloud.

Power ultrasound (US) transmits substantial amounts of small mechanical movements serving for particle detaching in membrane filtrations. This topic has been reviewed in recent years mainly focused on the mechanisms by which the flux is improved under specific processing conditions. US also been shown to improve food quality by changing physical properties and modifying the activity of enzymes and microorganisms. Surprisingly, limited information exists regarding on how the application of US results in terms of process and quality during membrane filtration of complex matrices such as liquid foods. This review highlights the recent advances in the use of US in membrane filtration processes focused in the manufacturing of foodstuffs and food ingredients, and perspectives of novel hybrid membrane-US systems that may be quite interesting for this field. The application of US in food membrane processing increases the flux, but the lack of standardization regarding to experimental conditions, make suitable comparisons impossible. In this sense, careful attention must be paid regarding to the ultrasonic intensity (UI), the membrane configuration and type of transducers and volume of the treated solution. Dairy products are the most studied application of US membrane food processing, but research has been mainly focused on flux enhancement; hitherto there have been no reports of how operational variables in these processes affect critical aspects such as quality and food safety. Also, studies performed at industrial scale and economical assessments are still missing. Application of US combined with membrane operations such as reverse osmosis (RO), forward osmosis (FO) and enzyme membrane bioreactors (EMBR) may result interesting for the production of value-added foods. In the perspective of the authors, the stagnation of the development of acoustic filtration systems in food is due more to a prejudice on this subject, rather than actual impedance due to the lack of technological development of transducers. This later has shown important advances in the last years making them suitable for tailor made applications, thus opening several research opportunities to the food engineering not yet explored.

A purification process of galacto-oligosaccharides (GOS), using three-stage serial nanofiltration (NF) units, operating under critical transmembrane pressure (TMPc) was designed. Three commercial flat-sheet membranes were tested at 53.5 °C and 65 °C, using GOS solutions at 20 and 40°Brix. Since one of the main drawbacks of NF for the purification of raw GOS is the removal of lactose, an enzymatic pre-hydrolysis step was also tested for producing a prehydrolyzed GOS and compared with non-hydrolyzed raw GOS. An empirical model showed that due to the increase in the solute concentration during batch NF, TMPc must be decreased with time to prevent fouling effects. Using NF serial system, the maximum GOS concentration achieved for raw GOS was 241 g/L and 156.8 g/L for pre-hydrolyzed GOS. Despite filtration times of the later were shorter, after three sequential batches, similar purities (∼55%) were obtained with both GOS solutions. Thus, the use of pre-hydrolyzed raw GOS as substrate for NF purification had two opposite effects: an improved flux due to lower lactose deposition on membrane, but also a lower GOS retention by the membrane, revealing a marginal gain in purification. The purities achieved were similar to those of commercial GOS, currently obtained by using conventional processes.

The flux decay of an ultrafiltration membrane bioreactor for the synthesis of galacto-oligosaccharides was modeled, by varying the processing conditions: temperature (40–60 °C), transmembrane pressure (2.5–4 bar) and cross-flow velocity (3.5–7 m/s) according to a 2 k design. Fouling mechanisms varied according to the operational condition, showing that the predominant mechanism were the intermediate fouling, which was associated to the higher flux decay due to the partial adsorption of the enzyme on the membrane, and the cake fouling mechanism, which was associated to those runs where the flux declined by around 20% because of the high concentration of substrate used (40% w/w). Strong statistical analysis allowed validation or rejection of initial adjustments given by a simple R-square statistical test, showing that misinterpretation of the fouling mechanism can be done under particular conditions, but also revealed that fouling equations have some limitations when drastic flux decay occurs or when this remains virtually unchanged. The experimental design also showed that temperature was the variable having the main positive effect on flux stability by decreasing the solution viscosity; however, the interaction between cross-flow velocity and transmembrane pressure had the main effect on flux decay.

Prebiotic oligosaccharides are short-chain carbohydrates that are not degraded by the enzymes of the human digestive tract. These molecules arrive intact to the lower gut to be selectively fermented by the probiotic bacteria, promoting several healthy effects to those who consume them. Prebiotic oligosaccharides are compounds of different nature: they can be extracted from plant tissues, principally by enzymatic hydrolysis of lignocelullosic material, or by using transglycosilation reactions mediated by carbohydrases. Regardless of their manufacturing strategy, the resulting solution is a mixture of oligosaccharides with different degree of polymerization as well as other not-desired contaminants of different molecular size that must be removed for improving the product purity. Therefore, membrane technology may offer interesting alternatives for such purpose. This chapter reports the main technological challenges, mechanisms, and advances, as well as trends and perspectives regarding the use of membrane technology as a strategy for manufacturing and purifying enzymatically produced oligosaccharides.

El objetivo de esta investigación es verificar la factibilidad de integración entre las teorías de inventarios y de sistemas expertos a través del diseño de un sistema informático basado en el conocimiento para apoyar el proceso de toma de decisiones en el área de logística y abastecimiento de una empresa forestal líder en Latino América. La metodología utilizada consistió en una revisión de publicaciones científicas de acceso online sobre modelos de inventarios, criterios de clasificación multicriterio ABC e identificación de los componentes de sistemas expertos basados en el conocimiento. Los resultados permiten disponer de un diseño de sistema experto soportado por planillas Excel, programación de macros en Visual Basic e interacción con un sistema informático de planificación de recursos empresariales. Las principales conclusiones son que es factible la integración entre la teoría de inventarios, la utilización de una clasificación multicriterio ABC con la teoría de sistemas expertos basados en conocimientos de tipo tácito y explícito y además, es posible lograr una reducción del 40% del capital de trabajo retenido en inventarios.

β-Galactosidase is one of the most important industrial enzymes, that has been used for many decades in the dairy industry. The main application of β-galactosidase is related to the production of low-lactose and lactose-free milk and dairy products, which are now common consumer goods in supermarket shelves. This is a well-established market that is expected to keep on growing as these products become more accessible to mid-income people worldwide. However, a fresh air has come into the β-galactosidase business as non-conventional applications arose in recent decades based on its transgalactosylation activity. This capacity is certainly a major asset for a commodity enzyme that can be used now as a catalyst for the upgrading of readily available and cheap lactose into high added-value glycosides in processes of organic synthesis in tune with green chemistry principles within the framework of sustainability. This is a reflection of a paradigm shift, where enzymes are now being considered as apt catalysts for the synthesis of valuable organic compounds. This article reviews the main applications of β-galactosidase, going from its conventional use related to its hydrolytic activity to the ongoing non-conventional applications in the synthesis of high added-value oligosaccharides based on its transgalactosylation activity.

The apple peel, a by-product of apple processing, has a high total phenolic content (TPC); however, these compounds can be highly thermosensitive and unstable. Therefore, the aim of this study was to determine the degradation kinetics of the TPC in apple peels during drum-drying as a stabilization and recovery method. Apple peels (Granny Smith) were dried at 110, 120, 130 or 140 °C for 250 s with a constant drum clearance (0.2 mm). TPC degradation exhibited first-order kinetics and their retentions at the end of the process were 73.13% at 110 °C, 57.28% at 120 °C, 43.40% at 130 °C and 21.10% at 140 °C. Finally, empirical models were significantly fitted to predict the TPC as the apple peels reached a certain level of dehydration, which may be useful from the processing standpoint and validate the use of drum-drying as a process tool for the recovery of apple industrial wastes.