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Abstract: Protein–protein interactions (PPI) are crucial for the establishment of life. However, its basic principles are still elusive and the recognition process is yet to be understood. It is important to look at the biomolecular structural space as a whole, in order to understand the principles behind conformation–function relationships. Since the application of an alanine scanning mutagenesis (ASM) study to the growth hormone it was demonstrated that only a small subset of residues at a protein–protein interface is essential for binding — the hot-spots (HS). Aromatic residues are some of the most typical HS at a protein–protein interface. To investigate the structural role of the interfacial aromatic residues in protein–protein interactions, we performed Molecular Dynamic (MD) simulations of protein–protein complexes in a water environment and calculated a variety of physical–chemical characteristics. ASM studies of single residues and of dimers or high-order clusters were performed to check for cooperativity within aromatic residues. Major differences were found between the behavior of non-HS aromatic residues and HS aromatic residues that can be used to design drugs to block the critical interactions or to predict major interactions at protein–protein complexes. [Copyright &y& Elsevier]

This paper presents experimental investigations into the development of feedforward and feedback control schemes for vibration control of a very flexible and high-friction manipulator system. A feedforward control scheme based on input shaping and low-pass filtering techniques and a strain feedback control scheme are examined. To study the effectiveness of the controllers, initially a collocated PD control is developed for control of rigid body motion. The performances of the controllers are assessed in terms of the input tracking capability and vibration reduction as compared to the response with PD control. Moreover, the robustness of the feedforward control schemes is discussed. Finally, a comparative assessment of the control strategies is presented. [Copyright &y& Elsevier]

An investigation into the dynamic modelling of flexible manipulator systems with different mechanical structures and actuation mechanisms is presented. Dynamic models of the systems are developed based on the assumed modes method considering linear displacements, quadratic displacements and the finite element method. Simulation and experimental exercises are performed with bang-bang torque and smooth displacement driven manoeuvres. To investigate the effects of centrifugal forces, slow and fast trajectories are implemented. Simulation and experimental results of the response of the flexible manipulators are presented in the time and frequency domains. Moreover, model validations are carried out by comparing the results to assess the performance of the modelling approaches. [ABSTRACT FROM AUTHOR]

Thirty-six male growing pigs were used to compare the component digestibility of legume seeds and the impact of diets and ileo-rectal anastomosis (IRA) on the morphology and enzyme activities of intestinal mucosa. The pigs were fed a control (C) diet based on casein or a diet in which 60% of crude protein (CP) was supplied by blue lupin (Lupinus angustifolius) (L) or pea (Pisum sativum) (P) seeds. Coefficient of total tract apparent digestibility (CTTAD) of organic matter (OM), CP and gross energy (GE) was lower in the L diet compared to the control diet. The pea-based diet presented intermediate CTTAD values of OM and GE. Coefficient of ileal apparent digestibility (CIAD) of OM and GE was lower in the legume-containing diets than with C. No significant differences were found for the CIAD of CP. There was a significant interaction between diet and IRA for villus height in the jejunum and crypt width in the ileum. Duodenal and jejunal crypt width was lower in the pigs fed the legume-containing diets compared to controls. The diet influenced the specific activity of most intestinal enzymes at various sites along the small intestine. Anastomosed pigs had higher spleen and small intestine weights and lower large intestine weights as compared to intact pigs. IRA influenced intestinal villus and crypt architecture but it had no significant effect on the activities of intestinal enzymes. [Copyright &y& Elsevier]

Tetrodotoxin (TTX) is a marine biotoxin whose biosynthesis is associated with the pufferfish. Its distribution is primarily focused in Asian and tropical marine areas. Currently, this group of toxins is classified as emerging in Europe, and its presence could be related to climate change. This incidence has prompted the European Union, with the European Food Safety Authority, to establish control and monitoring mechanisms for TTX in marine products in Europe. In this context, the development of analytical tools capable of ensuring the safety of food products, especially seafood and fish, is a crucial task. This study describes the development of a molecularly imprinted polymer (MIP) based electrochemical sensor for the analysis of TTX. The MIP was synthesized through the electropolymerization of a functional monomer, ortho -phenylenediamine in the presence of a dummy template, voglibose. The MIP sensor was constructed on a screen-printed gold electrode and characterized by cyclic voltammetry. Differential pulse voltammetry, using a redox probe ([Fe(CN) 6 ]3-/4-), was used in the analysis protocol. The developed sensor exhibited a linear response between 5.0 μg mL−1 and 25.0 μg mL−1, with a limit of detection of 1.14 μg mL−1. Its high imprinting efficiency conferred outstanding selectivity towards TTX. The sensor's applicability was confirmed through recovery assays on spiked mussel samples, achieving recoveries of 81.0 %, 110.2 %, and 102.5 % for external standard addition at 30.0, 44.0, and 60.0 μg kg−1, respectively, with relative standard deviations below 15 %. These results are comparable to those obtained using Hydrophilic Interaction Liquid Chromatography coupled with Tandem Mass Spectrometry, a validated method carried out by the European Reference Laboratory for Marine Biotoxins. Thus, the MIP sensor represents a portable, simple, and fast tool with essential analytical functionalities for the sampling phase and pre-selection of laboratory samples for analysis. [Display omitted] • Analysing tetrodotoxin can avoid severe or even fatal poisoning. • A simple and selective electrochemical MIP sensor was developed for tetrodotoxin. • A linear range from 5.0 to 25.0 μg mL−1 and an LOD of 1.14 μg mL−1 were achieved. • The sensor will allow significant time and cost savings in tetrodotoxin analysis. [ABSTRACT FROM AUTHOR]

This work presents a review on the technological advancements over the last decades of functional electrical stimulation based neuroprostheses to correct drop foot. Functional electrical stimulation is a technique that has been put into practice for several years now, and has been shown to functionally restore and rehabilitate individuals with movement disorders, such as stroke, multiple sclerosis and traumatic brain injury, among others. The purpose of this technical review is to bring together information from a variety of sources and shed light on the field's most important challenges, to help in identifying new research directions. The review covers the main causes of drop foot and its associated gait implications, along with several functional electrical stimulation-based neuroprostheses used to correct it, developed within academia and currently available in the market. These systems are thoroughly analyzed and discussed with particular emphasis on actuation, sensing and control of open- and closed-loop architectures. In the last part of this work, recommendations on future research directions are suggested. [ABSTRACT FROM AUTHOR]

Urea, in either solid form or in solution, is an additive commonly used to control the viscosity or act as a scavenger in MF (melamine-formaldehyde) and MUF (melamine-urea-formaldehyde) resins for particleboard production. The aim of this work was to evaluate the influence of adding urea to MF (melamine-formaldehyde) resin in terms of the water-resistance of the final particleboards. FTIR-ATR spectroscopy, adhesive bonding evaluation system (ABES) and gravimetric techniques were used. MF and MFU (melamine-formaldehyde-urea) resins were prepared. Urea was introduced as an additive, in different percentages (0, 10, 20, and 30% (on adhesive, dry basis), and citric acid was used as catalyst. Beech veneer strips were bonded together with these formulations and then tested in dry conditions and after immersion in water for 24 h. The effect of urea load on the resin curing reaction in dry and humid joints was studied. Particleboards were produced with MF and MFU (melamine formaldehyde urea) resins with different urea loads and using industrial recycled wood particles as raw material. Particleboard evaluation indicated that the water resistance of the final particleboards decreased linearly with urea addition. [ABSTRACT FROM AUTHOR]

Abstract: Environmental changes during the last 2 millennia in the Minho River tidal marsh (NW Portugal–Spain border) were reconstructed. Changes in the sources of organic matter (OM) delivered to the marsh were evaluated from elemental, isotopic and molecular composition using a 1m sediment core. Carbon isotopic composition (δ13C) and organic carbon to total nitrogen ratio (Corg/N) provided valuable information concerning the origin of the OM. These parameters indicated a major input from land plants, reaching a maximum at 1100–1200 and 1750–1850AD. These periods match with major flood events in the NW of the Iberian Peninsula, as reported by several authors. A significant reduction in the terrestrial signature occurred at 6–4cm (ca. 1960–1985AD), which is contemporaneous with the construction of several major dams on the Minho River. The distribution of selected lipid biomarkers, including n-alkanes, n-fatty acids and n-alkan-2-ones and specific parameters derived from the molecular distributions, were useful for refining bulk geochemical results. Long chain n-alkanes with an odd number of carbons are indicators of soil-and vascular plant-derived terrestrial OM and were dominant throughout the core. In addition, a greater contribution of plankton-derived lipids was observed in the sections corresponding to ca. 1960–1985AD (6–4cm) and ca. 100–200AD (96–94cm). Although different degradation rates for individual compounds might have partly affected biomarker assemblages, the variations could be attributed to a sharp decrease in the freshwater contribution to the Minho River estuary (dam construction) and a possible marine highstand, respectively. In addition, several parameters suggested changes in land use (including deforestation and farming) and probably the effects of mining exploitation during the Roman occupation of the area. [Copyright &y& Elsevier]

[Display omitted] • Valorisation of P. Pinaster, Ait by-products by steam pressure alkali extraction was studied. • Extraction yield, extracts reactivity and chemical composition were evaluated. • Maritime pine by-products were studied as raw materials for particleboard production. • Pinecones incorporation increases the final board quality. • Pine bark showed a noticeable influence on particleboard formaldehyde emission. Maritime pine (Pinus pinaster, Ait.) is one of the most important trees in the Iberian Peninsula forest. Its wood is mainly used in the wood-based panels production and for pulp and paper factories. The aim of this work was the valorisation of the main forest by-products of the P. Pinaster : bark, pinecones and needles. These organic by-products were widely used in small rural farms, but nowadays are mostly left in the forest, contributing to the forest fires problem. P. pinaster by-products were evaluated bearing in mind its wettability and chemical composition (evaluated by FTIR-ATR). Extracts were obtained from the bark, pinecones, and needles using a steam pressure extraction method (2% NaOH)", a simple extraction method used for the first time in the valorisation of biomass for its application in biomaterials. The structures of resorcinol, catechin and phloroglucinol appear in pine needles, pinecones and bark extracts, respectively. Extracts self-condensation curing process was evaluated by differential scanning calorimetry, and an automatic bonding evaluation system. For the first time particleboards were manufactured at a specific pressure of 4 MPa and 190 °C of press temperature for 3 min, with different percentages of the three maritime pine by-products, using a melamine-urea-formaldehyde resin and citric acid as particle binder. Due to the fast reactivity between polyphenols and formaldehyde, the influence of each by-product on the formaldehyde emission was also studied. The results show that it is possible to improve water resistance and internal bonding strength, and to control formaldehyde emission of particleboards, by using underutilized Maritime pine-based by-products in particleboards, replacing wood particles up to 20 % by weight. [ABSTRACT FROM AUTHOR]