Immobilization of b-galactosidase from kluyveromyces lactis onto a polysiloxane–polyvinyl alcohol magnetic (mPOS–PVA) composite for lactose hydrolysis

β-Galactosidase from Kluyveromyces lactis was covalently immobilized onto a mPOS–PVA, using glutaraldehyde as activating agent and its properties were evaluated. The enzymatic water insoluble derivative displayed the same optimum pH (6.5) and optimum temperature (50 °C) of the soluble enzyme. The apparent Km app and activation energy for both soluble and immobilized enzyme derivative were found to be not significantly different. The mPOS–PVA β-galactosidase preparation presented a higher operational and thermal stability than the soluble enzyme. This immobilized β-galactosidase also was effective in hydrolyzing lactose from milk. Hence, one can conclude that mPOS–PVA is an attractive and efficient support for β-galactosidase immobilization.Alban, the European Union Programme of High Level Scholarships for Latin America; Brazilian National Research Council (CNPq)

Raman spectrometry as a tool for an online control of a phototrophic biological nutrient removal process

UIDP/04378/2020 UIDB/04378/2020 PD/BD/114574/2016Real-time bioprocess monitoring is crucial for efficient operation and effective bioprocess control. Aiming to develop an online monitoring strategy for facilitating optimization, fault detection and decision-making during wastewater treatment in a photo-biological nutrient removal (photo-BNR) process, this study investigated the application of Raman spectroscopy for the quantifi-cation of total organic content (TOC), volatile fatty acids (VFAs), carbon dioxide (CO2 ), ammonia (NH3 ), nitrate (NO3 ), phosphate (PO4 ), total phosphorus (total P), polyhydroxyalkanoates (PHAs), total carbohydrates, total and volatile suspended solids (TSSs and VSSs, respectively). Specifically, partial least squares (PLS) regression models were developed to predict these parameters based on Raman spectra, and evaluated based on a full cross-validation. Through the optimization of spectral pre-processing, Raman shift regions and latent variables, 8 out of the 11 parameters that were investigated—namely TOC, VFAs, CO2, NO3, total P, PHAs, TSSs and VSSs—could be predicted with good quality by the respective Raman-based PLS calibration models, as shown by the high coefficient of determination (R2 > 90.0%) and residual prediction deviation (RPD > 5.0), and relatively low root mean square error of cross-validation. This study showed for the first time the high potential of Raman spectroscopy for the online monitoring of TOC, VFAs, CO2, NO3, total P, PHAs, TSSs and VSSs in a photo-BNR reactor.publishersversionpublishe

Effects of summary knowledge of results in motor skills acquisition

The effects of Summary Knowledge of Results (KR) were tested, using 30 volunteers and a positioning task in which a tennis ball had to be transported in 30 trials, following a specific sequence and with a target time of 3000 msec. Ten minutes after the acquisition phase, the transfer test was performed with 10 trials of different sequences and target times. The retention test took place 24 hours later with 10 trials of the same sequence and target time as the acquisition phase. In the transfer and retention tests, KR was not provided. The volunteers were randomly divided into three groups: G5 (KR every five trials); G3 (KR every three trials) and G100 (KR every trial). The results showed that G3 had a smaller absolute error than G100. However, G3 and G5 had a smaller constant error than G100. In general, the effects of G3 and G5 on motor skill acquisition could be caused by the lower KR frequency, which was 33% and 20% respectively.El efecto del conocimiento de los resultados (KR) resumen ha sido probado por 30 voluntarios en tarea de posicionamiento que requiere el transporte de una pelota de tenis en una secuencia específica con el tiempo objetivo de 3000 ms. en 30 ensayos. Diez minutos después de la fase de adquisición se jugó el test de transferencia con 10 ensayos con diferente secuencia y tempo objetivo. La retención se realizó la prueba 24 horas más tarde con la misma secuencia y tiempo objetivo fase de adquisición. En los testes de transferencia y retención de la CR no fue suministrado. Los voluntarios fueron divididos aleatoriamente en tres grupos: G5 (CR después de 5 ensayos); G3 (CR después de 3 ensayos) y G100 (CR en todos los ensayos). El resultado mostró que G3 tuvieron menor error absoluto que G100. Sin embargo, G3 y G5 se han registrado menor error constante que G100. En general, los efectos de G3 y G5 en la adquisición de las habilidades motoras pueden ser causados por la disminución de frecuencias CR, que fueron 33% y 20 %, respectivamente.O efeito do conhecimento de resultados (CR) sumário foi testado por 30 voluntários em uma tarefa de posicionamento a qual exigia o transporte de uma bola de tênis em uma sequência específica com tempo alvo de 3000 mseg. durante 30 tentativas. Dez minutos após a fase de aquisição foi desempenhado o teste de transferência com 10 tentativas com sequência e tempo alvo diferente. O teste de retenção foi realizado 24 horas mais tarde com a mesma sequência e tempo alvo da fase de aquisição. Nos testes de transferência e retenção o CR não foi fornecido. Os voluntários foram aleatoriamente divididos em três grupos: G5 (CR depois de 5 tentativas); G3 (CR depois de 3 tentativas) e G100 (CR em todas tentativas). O resultado mostrou que G3 apresentou menor erro absoluto que G100. Entretanto, G3 e G5 registraram menor erro constante que G100. Em geral, os efeitos de G3 e G5 sobre a aquisição de habilidades motoras podem ser causados pelas frequências reduzidas de CR, que foram de 33% e 20%, respectivamente

Measurement and analysis of needle penetration forces in industrial high-speed sewing machine

The industrial manufacturing of sewn products has always been one of the critical processes of the textile chain concerning quality assurance. Assuring the appropriate set-up and operation of all the machines, and thus the final seam quality, is a very complex task. Traditionally, this task is accomplished through empirical methods, with the machine setting and quality control relying on the skills of operators and technicians. This work presents an approach to a more knowledge-based and integrated process planning and control. A system was developed to measure and analyze the most important mechanical effects occurring during high-speed sewing. The paper will focus mainly on the measurement and evaluation of needle penetration and withdrawal force. After an overview of the system, the most important experimental results obtained in a series of experiments will be described

Effectiveness of different cellulose-based filtration materials against inhalation of SARS-CoV-2-like particles

The respiratory protection equipment (RPE) used by health professionals consists of an essential device to prevent infectious diseases, especially those caused by biological agents such as the coronavirus (SARS-CoV-2). The current epidemiological panorama is worrying, and the context of creation and production of the mask has emerged as an alternative to RPE to face the public health crisis worldwide. The aim of this work is to present a low-cost alternative as an FFP2-like filter for a reusable respirator face mask. This study presents the comparison of different cellulose-based filtering materials performed by retention testing, time saturation testing, aerosol penetration testing, nanoparticle (~140 nm) filtration testing, bacterial filtration efficiency (BFE), analysis of material morphology and usability. The reusable respirator face mask used in this study is an open-source innovation, using 3D printing. Cotton disc proved to be the best filter material for the reusable mask, with satisfactory results and a performance similar to that shown by the N95-type mask. The cotton disc ensured effectiveness over 6 h of use, and after that, the reusable respirator face mask (here, Delfi-TRON®) needed to be sanitized and replenished with a new cotton disc. Upon preliminary analyses of filtration efficiency, the selected filter was shown to be a low-cost biodegradable and biocompatible alternative.info:eu-repo/semantics/publishedVersio

Purification of antileukemic drugs through silica-based supported ionic liquids

L-asparaginase (LA) is an enzyme used as a biopharmaceutical for the treatment of acute lymphoblastic leukemia. LA can be produced via fermentation and its purification usually comprises several steps including precipitation, liquid-liquid extraction and chromatography techniques. Among these, ion exchange chromatography, which is often preceded by precipitation with salts as a first pre-chromatographic step, is the most used. However, theses common strategies for protein purification result in low yields and purity, requiring long processing times, while leading to a consequent increase of the process costs. Therefore, the demand for new cost-effective production/purification processes play now a priority role. This work aims the development of cost-effective technologies to purify LA from the complex fermentation medium from Bacillus Subtillis. Silica-based supported ionic liquids (SILs) are investigated as cost-effective purification materials for the target enzyme. The concentration of the extract from the fermentation, material/ extract from fermentation ratio and contact time effects in the purity and yield of LA were optimized. With this strategy, process costs, energy consumed, and waste generated, may be significantly decreased, which may lead to this biopharmaceutical price decrease and wider application.publishe