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The biodiesel industry currently generates large amounts of crude glycerol that are not marketed, thus accumulating, and causing environmental problems. This study evaluates the catalytic potential of Colombian olivine, using glycerol steam reforming to assess valorization alternatives for this by-product. The analyzed olivine was thermally treated at 1200 °C and reduced at 900 °C, then producing nanometer-sized Fe compounds. The catalyst was characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area, scanning electron microscopy (SEM), temperature-programmed reduction (TPR), and transmission electron microscopy (TEM). Calcined olivine increased glycerol conversion at 600 °C from 43% (without catalyst) to 96% with the formation of liquid-phase products such as aldehydes and carboxylic acids. In addition, syngas with H2/CO ratios of 1.1 and 1.5 was generated at reaction temperatures of 700 °C and 800 °C, respectively, with low CH4 content. Finally, it was established that olivine from Medellín, under the conditions used for glycerol steam reforming, is a viable and interesting alternative to valorize glycerol into gas- or liquid-phase products.

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INTRODUCTION: Patients with systemic lupus erythematosus (SLE) have a higher prevalence of insulin resistance (IR) and metabolic syndrome (MetS) than controls. OBJECTIVE: To evaluate IR in non-diabetic women with SLE by means of biomarkers using high-throughput metabolomic techniques. METHOD: Cross-sectional study in patients with SLE. A metabolomic approach was employed using ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry. MetS was evaluated according to NCEP-ATP III criteria. RESULTS: Seventy patients with SLE were included, out of whom 45 (64.2%) and 27 (38.5%) had IR and MetS, respectively. Patients with IR had a higher body mass index and hypertension more often than those without IR. Chronic damage and disease activity were not related to IR. A Quantose-IR score ≥ 63 was more common in patients with MetS (81.5 vs. 53.5%; p = 0.02). Quantose-IR score was also correlated with the number of criteria for MetS (r: 0.35; p = 0.003). CONCLUSIONS: In non-diabetic women with SLE, the prevalence of IR based on Quantose-IR score was 64.2%.

INTRODUCCIÓN: En lupus eritematoso sistémico (LES) es más frecuente la prevalencia de resistencia a la insulina (RI) y síndrome metabólico (SMet) que en controles. OBJETIVO: Evaluar la RI en mujeres no diabéticas con LES mediante biomarcadores usando técnicas metabolómicas de alta resolución. MÉTODO: Estudio transversal en pacientes con LES. Se empleó un abordaje metabolómico usando cromatografía de líquidos de ultra-alta resolución con espectrometría de masa de alta resolución. El SMet fue evaluado de acuerdo con los criterios NCEP-ATP III. RESULTADOS: Se incluyeron 70 pacientes con LES. Tuvieron RI y SMet 45 (64.2%) y 27 (38.5%), respectivamente. Pacientes con RI tenían un mayor índice de masa corporal e hipertensión con mayor frecuencia que aquellas sin RI. El daño crónico y la actividad de la enfermedad no se relacionaron con RI. Un puntaje de Quantose RI ≥ 63 fue más elevado en pacientes con SMet (81.5 vs 53.5%; p = 0.02). El puntaje Quantose RI también se correlacionó con el número de criterios para SMet (r: 0.35; p = 0.003). CONCLUSIONES: En mujeres con LES no diabéticas, la prevalencia de RI basada en el puntaje de Quantose RI fue del 64.2%.

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There are several specific solutions for accessing sensors and actuators present in any process or system through a TCP/IP network, either local or a wide area type like the Internet. The usage of sensors and actuators of different nature and diverse interfaces (SPI, I2C, analogue, etc.) makes access to them from a network in a homogeneous and secure way more complex. A framework, including both software and hardware resources, is necessary to simplify and unify networked access to these devices. In this paper, a set of open-source software tools, specifically designed to cover the different issues concerning the access to sensors and actuators, and two proposed low-cost hardware architectures to operate with the abovementioned software tools are presented. They allow integrated and easy access to local or remote sensors and actuators. The software tools, integrated in the free authoring tool Easy Java and Javascript Simulations (EJS) solve the interaction issues between the subsystem that integrates sensors and actuators into the network, called convergence subsystem in this paper, and the Human Machine Interface (HMI)-this one designed using the intuitive graphical system of EJS-located on the user's computer. The proposed hardware architectures and software tools are described and experimental implementations with the proposed tools are presented.

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Removal of ethanol from the fermentor during fermentation can increase productivity and reduce the costs for dewatering the product and coproduct. One approach is to recycle the fermentor contents through a stripping column, where a non-condensable gas removes ethanol to a condenser. Previous research showed that this approach is feasible. Savings of $0.03 per gallon were predicted at 34% corn dry solids. Greater savings were predicted at higher concentration. Now the feasibility has been demonstrated at over 40% corn dry solids, using a continuous corn liquefaction system. A pilot plant, that continuously fed corn meal at more than one bushel (25 kg) per day, was operated for 60 consecutive days, continuously converting 95% of starch and producing 88% of the maximum theoretical yield of ethanol. A computer simulation was used to analyze the results. The fermentation and stripping systems were not significantly affected when the CO(2) stripping gas was partially replaced by nitrogen or air, potentially lowering costs associated with the gas recycle loop. It was concluded that previous estimates of potential cost savings are still valid.

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Una cepa bacteriana nativa con capacidad de oxidar hierro ferroso y compuestos del azufre fue aislada a partir de efluentes y material de la mina de oro La Maruja, en el municipio de Marmato (Caldas), la cual fue identificada bioquímicamente como Acidithiobacillus ferrooxidans. Esta cepa fue evaluada en su capacidad de oxidar concentrados de sulfuros metálicos a dos diferentes concentraciones de pulpa y dos tamaños de partícula. Después de 15 días de biooxidación de los sulfuros se observó que, efectivamente, la bacteria mostró acción catalizadora sobre el proce-so de disolución del mineral.

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