Surface modification of banana-based lignocellulose fibres

Lignocellulosic raw materials were isolated from rachis of Musa acuminata Colla var. cavendish and characterised before and after chemical modification. The rachis was submitted to different mechanical treatments, milling and defibration, resulting in rachis powder and rachis fi bers, respectively. The chemical composition of these two samples was established and it was shown that rachis fibres exhibited higher polysaccharide and lignin contents and lower amounts of ash and extractives components, as compared with the rachis powder. The effects of solvent extrac tion, alkali treatment and chemical modification using phenyl isocyanate, maleic anhydride, alkenyl succinic anhydride and alkyl ketone dimer as grafting agents were studied. The materials were characterized in terms of chemical structure by ATR–FT-IR and 13C-CP-MAS-NMR spectroscopy, morphology by scanning electron microscopy and surface energies by inverse gas chromatography and contact angle measurements. The surface energy of these materials was found to be very close to other similar lignocellulosic materials. Finally, the water absorption of these materials before and after treatment was ascertained. The modified fibres showed considerable changes in ATR–FT-IR and 13C-CP-MAS-NMR spectra and surface properties, providing very convincing evidence that chemical grafting had occurred.info:eu-repo/semantics/publishedVersio

Laccase immobilization on bacterial nanocellulose membranes: antimicrobial, kinetic and stability properties

This work studied the physical immobilization of a commercial laccase on bacterial nanocellulose (BNC) aiming to identify the laccase antibacterial properties suitable for wound dressings. Physico-chemical analysis demonstrates that the BNC structure is manly formed by pure crystalline I cellulose. The pH optimum and activation energy of free laccase depends on the substrate employed corresponding to pH 6, 7, 3 and 57, 22, 48 kJ mol1 for 2,6-dimethylphenol (DMP), catechol and 2,2 -azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), respectively. The Michaelis-Menten constant (Km) value for the immobilized laccase (0.77 mM) was found to be almost double of that of the free enzyme (0.42 mM). However, the specific activities of immobilized and free laccase are similar suggesting that the cage-like structure of BNC allows entrapped laccase to maintain some flexibility and favour substrate accessibility. The results clearly show the antimicrobial effect of laccase in Gram-positive (92%) and Gram-negative (26%) bacteria and cytotoxicity acceptable for wound dressing applications.Andrea Zille (C2011-UMINHO-2C2T-01) acknowledges FCT funding from Programa Compromisso para a Ciência 2008, Portugal, FEDER funding on the Programa Operacional Factores de Competitividade - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007136 and UID/CTM/00264. Jorge Padrão and João P. Silva acknowledge Portuguese Foundation for Science and Technology (FCT) grants SFRH/BD/64901/2009 and SFRH/BPD/64958/2009 respectively. The authors Jorge Padrão, JoãoP. Silva and Fernando Dourado would like to thank the FCT StrategicProject PEst-OE/EQB/LA0023/2013, also to the Project “BioHealth −Biotechnology and Bioengineering approaches to improve healthquality”, Ref. NORTE-07-0124-FEDER-000027, co-funded by thePrograma Operacional Regional do Norte (ON.2-O Novo Norte),QREN, FEDER, and finnally to RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462)

Safety requirements for the design of collaborative robotic workstations in europe – a review

Industrial manufacturing is moving towards flexible and intelligent processes. Human-Robot Collaboration (HRC) has a pivotal role in smart factories due to a more versatile resource allocation that ultimately drives higher productivity and efficiency. The physical barriers that separate robots’ and humans’ workspaces are removed to facilitate HRC, which raises new safety concerns. To cope with this new robotics paradigm, regulatory legislation and international safety standards have been issued and are enforced for any machinery placed in factories. In this paper, we aim to shorten the gap between research projects and industry-ready robotic systems, by providing the guidelines and general requirements for collaborative robotic applications. We review the current international safety standards, certification procedures under the scope of European jurisdiction, and elaborate a literature review of papers related to safety for collaborative workstations.This work was supported by NORTE-06-3559-FSE-000018, integrated into the invitation NORTE-59-2018-41, aiming to hire highly-qualified human resources, co-financed by the Regional Operational Programme of the North 2020, thematic area of Competitiveness and Employment, through the European Social Fund (ESF)

Sub-m s−1^{-1} upper limits from a deep HARPS-N radial-velocity search for planets orbiting HD 166620 and HD 144579

Minimising the impact of stellar variability in Radial Velocity (RV) measurements is a critical challenge in achieving the 10 cm s$^{-1}$ precision needed to hunt for Earth twins. Since 2012, a dedicated programme has been underway with HARPS-N, to conduct a blind RV Rocky Planets Search (RPS) around bright stars in the Northern Hemisphere. Here we describe the results of a comprehensive search for planetary systems in two RPS targets, HD 166620 and HD 144579. Using wavelength-domain line-profile decorrelation vectors to mitigate the stellar activity and performing a deep search for planetary reflex motions using a trans-dimensional nested sampler, we found no significant planetary signals in the data sets of either of the stars. We validated the results via data-splitting and injection recovery tests. Additionally, we obtained the 95th percentile detection limits on the HARPS-N RVs. We found that the likelihood of finding a low-mass planet increases noticeably across a wide period range when the inherent stellar variability is corrected for using scalpels U-vectors. We are able to detect planet signals with $M\sin i \leq 1$ M$_\oplus$ for orbital periods shorter than 10 days. We demonstrate that with our decorrelation technique, we are able to detect signals as low as 54 cm s$^{-1}$, which brings us closer to the calibration limit of 50 cm s$^{-1}$ demonstrated by HARPS-N. Therefore, we show that we can push down towards the RV precision required to find Earth analogues using high-precision radial velocity data with novel data-analysis techniques.Comment: 7 tables, 24 figures (including those in appendix

Ultrasonography Reliability in the Detection of Inflammatory and Structural Abnormalities: An Exercise in Multiple Joints

Background Ultrasonography is an image technique that allows rheumatologists to visualize structural and inflammatory changes within a joint. The objective of this study was to assess the interobserver and intraobserver reliability of musculoskeletal ultrasound (US) in the detection of inflammatory and destructive joint changes in patients with polyarthritis. Methods A Delphi exercise was undertaken to standardize and adapt the EULAR-OMERACT elementary US definitions of inflammatory lesions (effusion, synovial hypertrophy, power Doppler, bone erosions, and synovitis) for each joint. Fifteen patients were analyzed, and video clips of 600 joints were collected. Each joint was scored for the presence of each elementary component, on 2 separate occasions, by 6 examiners. Interobserver and intraobserver agreement analysis was assessed through Fleiss κ coefficient (κ). Results Considering all patients and all joints, the interobserver values were highest for erosions and lowest for effusion (κ = 0.7314 and κ = 0.6044, respectively). When analyzing different regions, the highest interobserver agreement was for tibiotalar joint (κ = 0.8043) and the lowest for wrist (κ = 0.6767). Intraobserver reliability was excellent for each and all elementary components and anatomical region. Conclusions The present study showed either a good or excellent US interobserver and intraobserver reliability in elementary elements and anatomical region. This kind of US reliability exercises are important for standardization of exploration in everyday practice by reducing the variability associated with this imaging technique, and ensuring a greater degree of homogeneity and future comparability in the assessment of disease activity in polyarthritis patients.info:eu-repo/semantics/publishedVersio

Extraction, selection and comparison of features for an effective automated computer-aided diagnosis of Parkinson's disease based on [123I]FP-CIT SPECT images

Purpose This work aimed to assess the potential of a set of features extracted from [I-123] FP-CIT SPECT brain images to be used in the computer-aided "in vivo" confirmation of dopaminergic degeneration and therefore to assist clinical decision to diagnose Parkinson's disease.Methods Seven features were computed from each brain hemisphere: five standard features related to uptake ratios on the striatum and two features related to the estimated volume and length of the striatal region with normal uptake. The features were tested on a dataset of 652 [I-123] FP-CIT SPECT brain images from the Parkinson's Progression Markers Initiative. The discrimination capacities of each feature individually and groups of features were assessed using three different machine learning techniques: support vector machines (SVM), k-nearest neighbors and logistic regression.Results Cross-validation results based on SVM have shown that, individually, the features that generated the highest accuracies were the length of the striatal region (96.5%), the putaminal binding potential (95.4%) and the striatal binding potential (93.9%) with no statistically significant differences among them. The highest classification accuracy was obtained using all features simultaneously (accuracy 97.9%, sensitivity 98% and specificity 97.6%). Generally, slightly better results were obtained using the SVM with no statistically significant difference to the other classifiers for most of the features.Conclusions The length of the striatal region uptake is clinically useful and highly valuable to confirm dopaminergic degeneration "in vivo" as an aid to the diagnosis of Parkinson's disease. It compares fairly well to the standard uptake ratio-based features, reaching, at least, similar accuracies and is easier to obtain automatically. Thus, we propose its day to day clinical use, jointly with the uptake ratio-based features, in the computer-aided diagnosis of dopaminergic degeneration in Parkinson's disease

Antimicrobial enzyme immobilization in bacterial cellulose

This work studied the physical immobilization of laccase on bacterial nanocellulose (BNC) aiming to identify the enzyme antibacterial properties suitable for wound dressings. The pH optimum and activation energy of free laccase depends on the substrate employed. The Michaelis-Menten constant for the immobilized laccase was found to be almost double of that of the free enzyme. However, the specific activities of immobilized and free laccase are similar suggesting that entrapped laccase on BNC maintain some flexibility and favour substrate accessibility. The results clearly show the antimicrobial effect of laccase and cytotoxicity acceptable for wound dressing applications.A. Zille acknowledges funding from FCT within the scope of the project POCI-01-0145- FEDER-007136 and UID/CTM/00264.info:eu-repo/semantics/publishedVersio

Overview on protein extraction and purification using ionic-liquid-based processes

Proteins are one the most widely studied biomolecules with diverse functions and applications. Aiming at overcoming the current drawbacks of purification processes of proteins, the introduction of ionic liquids (ILs) has been a hot topic of research. ILs have been applied in the creation of aqueous biphasic systems (IL-based ABS), solid-phase extractions through poly(ionic liquid)s (PILs) and supported ionic-liquid phases (SILPs), and in the crystallization of proteins. In this sense, ILs have emerged as solvents, electrolytes or adjuvants, or as supported materials to tune the adsorption/affinity capacity aiming at developing an efficient, cost-effective, sustainable and green IL-based process for protein extraction. This review discusses different IL-based processes in the extraction and purification of proteins in the past years, namely IL-based aqueous biphasic systems (IL-based ABS), solid-phase extractions through PILs and SILPs, and protein crystallization. The type and structure of ILs applied and their influence in the different processes performance are also discussed.publishe

Querubismo

Nine cases of cherubism have been studdied with follouw up. Histologic examination can be conclusive in same cases, but a large experience on the part of the examiner is necesary. For a correct diagnosts in the every day practice, a Joint clinical, radiologic and histologic study is indispensable.Nove casos de querubismo foram estudados e acompanhados. O exame histológico pode ser conclusivo, em alguns casos, mas é necessário grande experiência. Sob o ponto de vista prático, para um diagnóstico corréto, é indispensável a valorisação de um estudo conjunto clínico, radiográfico e histológico

Recent strategies and applications for l-asparaginase confinement

l-asparaginase (ASNase, EC 3.5.1.1) is an aminohydrolase enzyme with important uses in the therapeutic/pharmaceutical and food industries. Its main applications are as an anticancer drug, mostly for acute lymphoblastic leukaemia (ALL) treatment, and in acrylamide reduction when starch-rich foods are cooked at temperatures above 100 °C. Its use as a biosensor for asparagine in both industries has also been reported. However, there are certain challenges associated with ASNase applications. Depending on the ASNase source, the major challenges of its pharmaceutical application are the hypersensitivity reactions that it causes in ALL patients and its short half-life and fast plasma clearance in the blood system by native proteases. In addition, ASNase is generally unstable and it is a thermolabile enzyme, which also hinders its application in the food sector. These drawbacks have been overcome by the ASNase confinement in different (nano)materials through distinct techniques, such as physical adsorption, covalent attachment and entrapment. Overall, this review describes the most recent strategies reported for ASNase confinement in numerous (nano)materials, highlighting its improved properties, especially specificity, half-life enhancement and thermal and operational stability improvement, allowing its reuse, increased proteolysis resistance and immunogenicity elimination. The most recent applications of confined ASNase in nanomaterials are reviewed for the first time, simultaneously providing prospects in the described fields of application.publishe