The Bul1/2 Alpha-Arrestins Promote Ubiquitylation and Endocytosis of the Can1 Permease upon Cycloheximide-Induced TORC1-Hyperactivation

Selective endocytosis followed by degradation is a major mechanism for downregulating plasma membrane transporters in response to specific environmental cues. In Saccharomyces cerevisiae, this endocytosis is promoted by ubiquitylation catalyzed by the Rsp5 ubiquitin-ligase, targeted to transporters via adaptors of the alpha-arrestin family. However, the molecular mechanisms of this targeting and their control according to conditions remain incompletely understood. In this work, we dissect the molecular mechanisms eliciting the endocytosis of Can1, the arginine permease, in response to cycloheximide-induced TORC1 hyperactivation. We show that cycloheximide promotes Rsp5-dependent Can1 ubiquitylation and endocytosis in a manner dependent on the Bul1/2 alpha-arrestins. Also crucial for this downregulation is a short acidic patch sequence in the N-terminus of Can1 likely acting as a binding site for Bul1/2. The previously reported inhibition by cycloheximide of transporter recycling, from the trans-Golgi network to the plasma membrane, seems to additionally contribute to efficient Can1 downregulation. Our results also indicate that, contrary to the previously described substrate-transport elicited Can1 endocytosis mediated by the Art1 alpha-arrestin, Bul1/2-mediated Can1 ubiquitylation occurs independently of the conformation of the transporter. This study provides further insights into how distinct alpha-arrestins control the ubiquitin-dependent downregulation of a specific amino acid transporter under different conditions.     

Liquid Biopsy: A New Translational Diagnostic and Monitoring Tool for Musculoskeletal Tumors

Soft tissue and bone sarcomas represent a group of aggressive neoplasms often accompanied by dismal patient prognosis, especially when distant metastases are present. Moreover, effective treatment can pose a challenge, as recurrences are frequent and almost half of patients present with advanced disease. Researchers have unveiled the molecular abnormalities implicated in sarcomas’ carcinogenesis, paving the way for novel treatment strategies based on each individual tumor’s characteristics. Therefore, the development of new techniques aiding in early disease detection and tumor molecular profiling is imperative. Liquid biopsy refers to the sampling and analysis of patients’ fluids, such as blood, to identify tumor biomarkers, through a variety of methods, including qRT-PCR, qPCR, droplet digital PCR, magnetic microbeads and digital PCR. Assessment of circulating tumor cells (CTCs), circulating free DNA (ctDNA), micro RNAs (miRs), long non-coding RNAs (lncRNAs), exosomes and exosome–associated proteins can yield a plethora of information on tumor molecular signature, histologic type and disease stage. In addition, the minimal invasiveness of the procedure renders possible its wide application in the clinical setting, and, therefore, the early detection of the presence of tumors. In this review of the literature, we gathered information on biomarkers assessed through liquid biopsy in soft tissue and bone sarcoma patients and we present the information they can yield for each individual tumor type.     

Fatigue assessment of offshore wind turbines on monopile foundations using multi‐band modal expansion

Offshore wind turbines (OWTs) are subjected to both quasi‐static loads originating from variations in the thrust force and dynamic loads linked to turbulence, waves and turbine dynamics. Both types of loads contribute to fatigue life progression and thus define the turbine's age. As a structural health monitoring solution, one could thus directly measure the stress history at fatigue critical locations. However, for OWTs on monopile foundations some fatigue critical locations are located below the seabed. Installing strain sensors at these hotspots is therefore impossible for existing wind turbines. This measurement restriction is overcome by reconstructing the full‐field response of the structure based on the limited number of accelerometers and strain sensors (installed at a few easily accessible locations) and a calibrated finite element model of the system. The system model uses a multi‐band modal expansion approach constituted of the quasi‐static and dynamic contributions. These contributions are superimposed to reconstruct the stress history at all degrees of freedom of the finite element model, and the subsequent assess fatigue life consumption at all fatigue hot spots of the OWT. In this paper, the proposed virtual sensing technique is validated by predicting the stresses in the transition piece with 12 days of consecutive measurements from an operational OWT. The data set contains both variations in environmental and operating conditions as well as extreme events. Finally, a full‐field strain assessment in the tower and foundation system of the OWT is demonstrated. Copyright © 2017 John Wiley & Sons, Ltd.     

Heat transfer and performance characteristics of axial cooling fans with downstream guide vanes

This study examines experimentally the effect of stators on the performance and heat transfer characteristics of small axial cooling fans. A single fan impeller, followed by nine stator blades in the case of a complete stage, was used for all the experimental configurations. Performance measurements were carried out in a constant speed stage performance test rig while the transient liquid crystal technique was used for the heat transfer measurements. Full surface heat transfer coefficient distributions were obtained by recording the temperature history of liquid crystals on a target plate. The experimental data indicated that the results are highly affected by the flow conditions at the fan outlet. Stators can be beneficial in terms of pressure drop and efficiency, and thus more economical operation, as well as, in the local heat transfer distribution at the wake of the stator blades if the fan is installed very close to the cooling object. However, as the separation distance increases, enhanced heat transfer rate in the order of 25% is observed in the case of the fan impeller.     

Modelling flow and filtration in liquid composite moulding of nanoparticle loaded thermosets

This paper presents analytical and numerical models of liquid moulding of hybrid composites. An 1-D analytical solution of Darcy’s problem, accompanied by nanoparticle filtration kinetics and conservation, has been developed. A non-linear finite difference model incorporating variations in permeability, porosity and viscosity as a function of local nanoparticle loading was formulated. Comparison of the two models allowed verification of their validity, whilst a mesh sensitivity study demonstrated the convergence of the numerical scheme. The limits of validity of the analytical solution were established over a range of infiltration lengths and filtration rates for different nanoparticle loadings. The analytical model provides an accurate and efficient approximation of through thickness infusion of hybrid composites, whereas use of the numerical scheme is necessary for accurate simulation of in-plane filling processes. The models developed here can serve as the basis of process design/optimisation for the production of hybrid composites with controlled distribution of nano-reinforcement.     

RTM processing and electrical performance of carbon nanotube modified epoxy/fibre composites

This investigation focuses on nanoparticle filtration in the processing of multiscale carbon and glass fibre composites via resin transfer moulding. Surface modified and unmodified carbon nanotubes (CNTs) were incorporated into a commercial epoxy resin. The dispersion quality was evaluated using electrical measurements of the liquid suspensions. The manufacturing process was adapted to the challenges posed by the modified rheological behaviour of the CNT loaded resin. Nanoparticle filtration was observed; with some of the unmodified systems following so called ‘cake filtration’ behaviour. This resulted in nonlinear flow behaviour that deviated from the ideal response observed in RTM filling in conventional composites. The electrical conductivity of relatively high fibre volume fraction multiscale carbon and glass laminates increased by less than an order of magnitude with the addition of the nanotubes.     

Assessment of tremor activity in the Parkinson's disease using a set of wearable sensors

Tremor is the most common motor disorder of Parkinson's disease (PD) and consequently its detection plays a crucial role in the management and treatment of PD patients. The current diagnosis procedure is based on subject-dependent clinical assessment, which has a difficulty in capturing subtle tremor features. In this paper, an automated method for both resting and action/postural tremor assessment is proposed using a set of accelerometers mounted on different patient's body segments. The estimation of tremor type (resting/action postural) and severity is based on features extracted from the acquired signals and hidden Markov models. The method is evaluated using data collected from 23 subjects (18 PD patients and 5 control subjects). The obtained results verified that the proposed method successfully: 1) quantifies tremor severity with 87 % accuracy, 2) discriminates resting from postural tremor, and 3) discriminates tremor from other Parkinsonian motor symptoms during daily activities.     

In-depth analysis and evaluation of diffusive glioma models

Glioma is one of the most aggressive types of brain tumor. Several mathematical models have been developed during the past two decades, toward simulating the mechanisms that govern the development of glioma. The most common models use the diffusion-reaction equation (DRE) for simulating the spatiotemporal variation of tumor cell concentration. Nevertheless, despite the applications presented, there has been little work on studying the details of the mathematical solution and implementation of the 3-D diffusion model and presenting a qualitative analysis of the algorithmic results. This paper presents a complete mathematical framework on the solution of the DRE using different numerical schemes. This framework takes into account all characteristics of the latest models, such as brain tissue heterogeneity, anisotropic tumor cell migration, chemotherapy, and resection modeling. The different numerical schemes presented have been evaluated based upon the degree to which the DRE exact solution is approximated. Experiments have been conducted both on real datasets and a test case for which there is a known algebraic expression of the solution. Thus, it is possible to calculate the accuracy of the different models.     

Antibacterial Surface Coatings from Zinc Oxide Nanoparticles Embedded in Poly(N‐isopropylacrylamide) Hydrogel Surface Layers

Despite multiple research approaches to prevent bacterial colonization on surfaces, device‐associated infections are currently responsible for about 50% of nosocomial infections in Europe and significantly increase health care costs, which demands development of advanced antibacterial surface coatings. Here, novel antimicrobial composite materials incorporating zinc oxide nanoparticles (ZnO NP) into biocompatible poly(N‐isopropylacrylamide) (PNIPAAm) hydrogel layers are prepared by mixing the PNIPAAm prepolymer with ZnO NP, followed by spin‐coating and photocrosslinking. Scanning electron microscopy (SEM) characterization of the composite film morphology reveals a homogeneous distribution of the ZnO NP throughout the film for every applied NP/polymer ratio. The optical properties of the embedded NP are not affected by the matrix as confirmed by UV‐vis spectroscopy. The nanocomposite films exhibit bactericidal behavior towards Escherichia coli (E. coli) for a ZnO concentration as low as ≈0.74 μg cm^?2 (1.33 mmol cm^?3), which is determined by inductively coupled plasma optical emission spectrometry. In contrast, the coatings are found to be non‐cytotoxic towards a mammalian cell line (NIH/3T3) at bactericidal loadings of ZnO over an extended period of seven days. The differential toxicity of the ZnO/hydrogel nanocomposite thin films between bacterial and cellular species qualifies them as promising candidates for novel biomedical device coatings.     

Determination of Phthalates into Vegetable Oils by Isotopic Dilution Gas Chromatography Mass Spectrometry

The presented method for the determination of a number of phthalic acid esters into oily media is based on their extraction by acetonitrile with precipitation under freezing and subsequent solid-phase extraction using alumina. This technique was checked as the best procedure to separate lipophilic phthalates from fatty media achieving elimination of contamination by excess use of solvents. Extracted phthalates are determined in acetonitrile solutions with gas chromatography in conjunction to isotopic dilution mass spectrometry using D4 isotopic labeled derivatives. Full validation of the method was carried out and background effect was examined. Method calibration for extraction from oil resulted in limit of detection (LOD) of 7–10 ng g^?1 and limit of quantification (LOQ) of 20–50 ng g^?1 for DMP, DEP, DiBP, DBP, DEHP, and BBP and in LOD 500 ng g^?1 and LOQ of 1,500 ng g^?1 for DiNP and DiDP. Real samples of virgin olive oil from olive press establishments from three different areas were analyzed and the phthalates content was below detection limit for all phthalic esters under consideration for nonindustrial areas and in measurable concentrations for industrial areas specifically with regard to DiBP.