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Oligodendrocyte progenitor cell (OPC)-mediated remyelination declines with ageing. We have determined the proteome of neonatal, young and aged rat OPCs using quantitative MS-proteomics. We identify increases in myelin proteins as well as changes in inflammation, cholesterol biosynthesis and protein homeostasis pathways in OPCs with ageing. These data provide a resource to study age-associated changes in OPCs that may contribute to the age-related decrease in oligodendrogliogenesis., Graphical Abstract Highlights • Quantitative proteome of neonatal, young, and aged OPCs. • 50% of the proteome is differentially expressed between neonatal and adult OPCs. • Myelin proteins are increased, and cholesterol synthesis proteins decreased with age. • Proteins associated with other neurodegenerative diseases are increased in aged OPCs., Following central nervous system (CNS) demyelination, adult oligodendrocyte progenitor cells (OPCs) can differentiate into new myelin-forming oligodendrocytes in a regenerative process called remyelination. Although remyelination is very efficient in young adults, its efficiency declines progressively with ageing. Here we performed proteomic analysis of OPCs freshly isolated from the brains of neonate, young and aged female rats. Approximately 50% of the proteins are expressed at different levels in OPCs from neonates compared with their adult counterparts. The amount of myelin-associated proteins, and proteins associated with oxidative phosphorylation, inflammatory responses and actin cytoskeletal organization increased with age, whereas cholesterol-biosynthesis, transcription factors and cell cycle proteins decreased. Our experiments provide the first ageing OPC proteome, revealing the distinct features of OPCs at different ages. These studies provide new insights into why remyelination efficiency declines with ageing and potential roles for aged OPCs in other neurodegenerative diseases.

Protein–RNA interactions regulate all aspects of RNA metabolism and are crucial to the function of catalytic ribonucleoproteins. Until recently, the available technologies to capture RNA-bound proteins have been biased toward poly(A) RNA-binding proteins (RBPs) or involve molecular labeling, limiting their application. With the advent of organic–aqueous phase separation–based methods, we now have technologies that efficiently enrich the complete suite of RBPs and enable quantification of RBP dynamics. These flexible approaches to study RBPs and their bound RNA open up new research avenues for systems-level interrogation of protein–RNA interactions.

The paper presents a bespoke power measurement system that has been designed and implemented on a Rubber Tyre Gantry, RTG crane at the Port of Felixstowe, PoF. The design of a novel system topology which is centred around a Beckhoff computer, as well as the specifications of the various transducers used, is detailed. To complement the hardware installation, a bespoke data analysis tool has also been developed in MATLAB, an overview of its operation and use are presented. The system allows for the characterisation of the cranes’ various motors during operational hours; furthermore, the data collected has been used to verify simulations of RTGs developed as part of the overall PoF project. The measurement system was installed on RTG1 at the port in March 2016.

Solar radiation along with other weather variables are commonly processed on typical meteorological years (TMYs) to be applied in the design of various energy systems. However, in several regions of the world, solar radiation data usually lacks a suitable and/or representative measurement, which leads to its modeling and prediction to properly fill this information in the databases. Consequently, the accuracy of these models can influence the viability and proper design of such energy systems. Within this context, the present contribution aims to assess the quality of solar radiation data included in the most recent TMY databases with Brazilian data and how that quality can influence the selection of months that create TMYs as well as the building performance simulation (BPS) results. Because two different approaches to generate the solar radiation data are used, we evaluate the global horizontal irradiation data in the two latest versions of recent Brazilian TMY databases against the corresponding satellite-derived ones obtained from the POWER database (NASA). Simultaneously, as another alternative approach, global solar radiation data are calculated for the same studied locations and period through the modeling method used to generate the current version of the International Weather for Energy Calculations (IWEC2), and its performance is also compared against the corresponding reanalysis data (POWER). Finally, a set of case studies applying the local building performance regulations are exhaustively analyzed to quantify the impact of the uncertainty of solar radiation models on BPS results throughout Brazil. The results indicate that the accuracy of solar radiation models can highly influence the resulting TMY configurations. These changes can drive differences up to 40% on the prediction of the ideal annual loads of the residential buildings while, regardless of design performance, differences lower than 10% are found for the commercial case studies in most locations. Conversely, the prediction of peak loads for cooling shows to be more sensitive to the climate data changes in the commercial buildings than in the residential ones.

Climatic zoning is frequently used in building energy efficiency regulations. However, there is no consensus about which climatic zoning method should be used for a given purpose. This study aims to verify if building performance data is necessary to propose a climatic zoning for building energy efficiency regulations. First, an exploratory data analysis was performed based on correlations of climatic variables and building performance results from an office building in 411 Brazilian cities. The same building performance results were used to perform a preliminary assessment of seven climatic zoning methods: two globally well-known methods (ASHRAE 169 and Koppen-Geiger), the current Brazilian regulation method (NBR 15220), a proposal for a new Brazilian regulation (Roriz) and three alternative methods for climatic zoning proposed by the authors. The alternative methods were named as Data-driven, Enhanced degree-day and Decision tree method. The final assessment included 21 variations in the office building. The performance of each climatic zoning method was analysed according to two indicators: uniqueness and dispersion. This study shows the importance of building performance data to improve the quality of climatic zonings for building energy efficiency regulations.

Trypanosoma cruzi depends on the effectiveness of redox metabolism to survive and ensure infection in the host. Homeostasis of redox metabolism in T. cruzi is achieved by the actions of several proteins that differ in many aspects from host proteins. Although extensive research has been performed examining hydroperoxide cytosolic antioxidant defense centered on trypanothione, the mechanisms of mitochondrial antioxidant defense are not yet known. The aim of this study was to elucidate the partners of TcMPx antioxidant pathway and to determine the influence of the cellular context (physiological versus oxidative stress). Through co-precipitation coupled with a mass spectrometry approach, a variety of proteins were detected under physiological and oxidative stress conditions. Interestingly, functional category analysis of the proteins identified under physiological conditions showed that they were involved in the stress response, oxidoreduction, thiol transfer, and metabolic processes; this profile is distinct under oxidative stress conditions likely due to structural alterations. Our findings help to elucidate the reactions involving TcMPx and most importantly also reveal that this protein is present throughout the cell and that its interaction partners change following oxidative stress exposure. The involvement and significance of the proteins found to interact with TcMPx and other possible functions for this protein are discussed widening our knowledge regarding T. cruzi mitochondrial antioxidant defenses.

The paper summarises the most important results of selected experimental programmes on static and fatigue strength of heavy loaded components and joints made of glass reinforced plastic (GRP) composites, having been recently performed in fatigue laboratory of the SVUM a.s. research and testing institute. Components like GRP trailer leaf springs, springs for railway freight vehicles are addressed, along with heavy loaded joints like stud connections in rotor blade roots at different loading and environmental conditions. It was confirmed during the different kind of tests that fatigue damage accumulation can be well monitored particularly when there are no defects or imperfections in the material. Then the damage curve usually had the typical three-stages sigmoidal shape. In case of fatigue tests of stud joints, where damage was located into the bonded area inside the specimen, temperature changes were considerably more sensitive than displacement and detailed temperature monitoring indicated weak areas in the full scale model specimens. Sudden break was mostly characteristic for defect material with insufficient wet out or with different bubbles and voids. After a more detailed analysis of fatigue tests, some further links like connections between total fatigue life and initial stiffness or initial temperature increase gradient were indicated.

The paper presents results of a partial experimental programme of evaluation of static mechanical and fatigue properties of long glass-fiber reinforced polymer composite material with a multiaxial orientation of glass fibers to be used for a manufacture of the flywheel hub disc, the main component of the storage unit accumulating kinetic energy of a vehicle during braking for further use during acceleration. Though humidity is not supposed to be an issue in operation of the unit, an experimental programme evaluating the material static strength and durability under combination of static load with vibration component was carried out to complete the overall general material characterisation. Study of an effect of absorbed moisture was a part of the experimental work. Water absorption was a long-term process, without saturation even after several months. Degradation of strength and fatigue properties due to the absorbed distilled water was confirmed for this material. The material sensitivity on vibration component of the load, even with quite low amplitude of 10% of the static load was ascertained. Damage accumulation and continuous stiffness reduction during fatigue tests, which rate was connected with final durability, was an important phenomenon.

This paper presents the design evolution process of a composite leaf spring for freight rail applications. Three designs of eye-end attachment for composite leaf springs are described. The material used is glass fibre reinforced polyester. Static testing and finite element analysis have been carried out to obtain the characteristics of the spring. Load-deflection curves and strain measurement as a function of load for the three designs tested have been plotted for comparison with FEA predicted values. The main concern associated with the first design is the delamination failure at the interface of the fibres that have passed around the eye and the spring body, even though the design can withstand 150 kN static proof load and one million cycles fatigue load. FEA results confirmed that there is a high interlaminar shear stress concentration in that region. The second design feature is an additional transverse bandage around the region prone to delamination. Delamination was contained but not completely prevented. The third design overcomes the problem by ending the fibres at the end of the eye section.