École Polytechnique Fédérale de Lausanne
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Inkjet-Printed Carbon Nanotube Electrodes Modified with Dimer-captosuccinic Acid-Capped Fe3O4 Nanoparticles on Reduced Graphene Oxide Nanosheets for Single-Drop Determination of Trifluoperazine
No full textHere we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsy-chotic drug trifluoperazine (TFP). The sensor was build using inkjet-printed carbon nanotube (CNT) electrodes which were modified with dimercaptosuccinic acid (DMSA) coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron mi-croscopies (TEM and FE-SEM), X-ray powder diffraction, zeta potential measurements, DLS and electrochemical methods (CV and EIS). Developed sensor, best operated at pH 7 in Britton-Robinson buffer solution (BRBS), shown linear electro-catalytic activity in the concentration range from 1 to 50 µM TFP, with a low detection limit of 0.54 µM and excellent se-lectivity, repeatability and reproducibility with RSD of 2.4%. A voltammetric approach using the square wave voltamme-try (SWV) was used as a sensitive technique under optimized conditions for the analytical determination of sub-micromolar amounts of TFP. Bare CNT, RGO- and DMSA/Fe3O4-modified CNT resulted in a less electrocatalytic activity then DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticles decorated graphene nanosheets can offer a tool for point-of-care applications of the sensor in biomedicine.LEP
Building a Mirror World for Venice
No full textBetween 2012 and 2019, ‘TheVeniceTime Machine Project’ developed a new methodology for modelling the past, present, and future of a city. This methodology is based on two pillars: (a) the vast digitisation and processing of the selected city’s historical records, (b) the digitisation of the city itself, another vast undertaking. The combination of these two processes has the potential to create a new kind of historical information system organised around a diachronic digital twin of a city.DHLA
Tractostorm: The what, why, and how of tractography dissection reproducibility
No full textInvestigative studies of white matter (WM) brain structures using diffusion MRI (dMRI) tractography frequently require manual WM bundle segmentation, often called "virtual dissection." Human errors and personal decisions make these manual segmentations hard to reproduce, which have not yet been quantified by the dMRI community. It is our opinion that if the field of dMRI tractography wants to be taken seriously as a widespread clinical tool, it is imperative to harmonize WM bundle segmentations and develop protocols aimed to be used in clinical settings. The EADC-ADNI Harmonized Hippocampal Protocol achieved such standardization through a series of steps that must be reproduced for every WM bundle. This article is an observation of the problematic. A specific bundle segmentation protocol was used in order to provide a real-life example, but the contribution of this article is to discuss the need for reproducibility and standardized protocol, as for any measurement tool. This study required the participation of 11 experts and 13 nonexperts in neuroanatomy and "virtual dissection" across various laboratories and hospitals. Intra-rater agreement (Dice score) was approximately 0.77, while inter-rater was approximately 0.65. The protocol provided to participants was not necessarily optimal, but its design mimics, in essence, what will be required in future protocols. Reporting tractometry results such as average fractional anisotropy, volume or streamline count of a particular bundle without a sufficient reproducibility score could make the analysis and interpretations more difficult. Coordinated efforts by the diffusion MRI tractography community are needed to quantify and account for reproducibility of WM bundle extraction protocols in this era of open and collaborative science.LTS5This is an open access article under the terms of the Creative Commons Attribution License
Contribution of Genetic Background and Data Collection on Adverse Events of Anti-human Immunodeficiency Virus (HIV) Drugs (D:A:D) Clinical Risk Score to Chronic Kidney Disease in Swiss HIV-infected Persons With Normal Baseline Estimated Glomerular Filtration Rate
No full textBackground. In human immunodeficiency virus (HIV), the relative contribution of genetic background, clinical risk factors, and antiretrovirals to chronic kidney disease (CKD) is unknown.Methods. We applied a case-control design and performed genome-wide genotyping in white Swiss HIV Cohort participants with normal baseline estimated glomerular filtration rate (eGFR >90 mL/minute/1.73 m(2)). Univariable and multivariable CKD odds ratios (ORs) were calculated based on the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) score, which summarizes clinical CKD risk factors, and a polygenic risk score that summarizes genetic information from 86 613 single-nucleotide polymorphisms.Results. We included 743 cases with confirmed eGFR drop to = 25% eGFR drop to <90 mL/minute/1.73 m(2) (n = 599), and 322 controls (eGFR drop <15%). Polygenic risk score and D:A:D score contributed to CKD. In multivariable analysis, CKD ORs were 2.13 (95% confidence interval [CI], 1.55-2.97) in participants in the fourth (most unfavorable) vs first (most favorable) genetic score quartile; 1.94 (95% CI, 1.37-2.65) in the fourth vs first D:A:D score quartile; and 2.98 (95% CI, 2.02-4.66), 1.70 (95% CI, 1.29-2.29), and 1.83 (95% CI, 1.45-2.40), per 5 years of exposure to atazanavir/ritonavir, lopinavir/ritonavir, and tenofovir disoproxil fumarate, respectively. Participants in the first genetic score quartile had no increased CKD risk, even if they were in the fourth D:A:D score quartile.Conclusions. Genetic score increased CKD risk similar to clinical D:A:D score and potentially nephrotoxic antiretrovirals. Irrespective of D:A:D score, individuals with the most favorable genetic background may be protected against CKD.UPFELLA
Selective Recruitment of Arm Motoneurons in Nonhuman Primates Using Epidural Electrical Stimulation of the Cervical Spinal Cord
No full textRecovery of reaching and grasping ability is the priority for people with cervical spinal cord injury (SCI). Epidural electrical stimulation (EES) has shown promising results in improving motor control after SCI in various animal models and in humans. Notably, the application of stimulation bursts with spatiotemporal sequences that reproduce the natural activation of motoneurons restored skilled leg movements in rodent and nonhuman primate models of SCI. Here, we studied whether this conceptual framework could be transferred to the design of cervical EES protocols for the recovery of reaching and grasping in nonhuman primates. We recorded muscle activity during a reaching and grasping task in a macaque monkey and found that this task involves a stereotypical spatiotemporal map of motoneuron activation. We then characterized the specificity of a spinal implant for the delivery of EES to cervical spinal segments in the same animal. Finally, we combined these results to design a simple stimulation protocol that may reproduce natural motoneuron activation and thus facilitate upper limb movements after injury.LSBIUPCOURTIN
Long-term functionality of a soft electrode array for epidural spinal cord stimulation in a minipig model
No full textLong-term biointegration of man-made neural interfaces is influenced by the mechanical properties of the implant materials. Substantial experimental work currently aims at replacing conventional hard implant materials with soft alternatives that can favour a lower immune response. Here we assess the performance of a soft electrode array implanted in the spinal epidural space of a minipig model for a period of 6 months. The electrode array includes platinum-silicone electrode contacts and elastic thin-film gold interconnects embedded in silicone. In-vivo electrode impedance and voltage transients were monitored over time. Following implantation, epidural stimulation produced muscle-specific evoked potentials and visible muscle contractions. Over time, postoperative and stimulation induced changes in electrode impedance were observed. Such trends provide a basis for future technological improvements aiming at ensuring the stability of soft implantable electrodes for neural interfacing.LSB
The busy lives of academics have hidden costs — and universities must take better care of their faculty members
No full textLMN
Introduction to the Minitrack on Strategy, Information, Technology, Economics, and Society (SITES)
No full textOESCopyright: CC BY-NC-ND 4.
Susceptibility to infection in early life: a growing role for human genetics
No full textThe unique vulnerability to infection of newborns and young infants is generally explained by a constellation of differences between early-life immune responses and immune responses at later ages, often referred to as neonatal immune immaturity. This developmental view, corroborated by robust evidence, offers a plausible, population-level description of the pathogenesis of life-threatening infectious diseases during the early-life period, but provides little explanation on the wide inter-individual differences in susceptibility and resistance to specific infections during the first months of life. In this context, the role of individual human genetic variation is increasingly recognized. A life-threatening infection caused by an opportunistic pathogen in an otherwise healthy infant likely represents the first manifestation of an inborn error of immunity. Single-gene disorders may also underlie common infections in full-term infants with no comorbidities or in preterm infants. In addition, there is increasing evidence of a possible role for common genetic variation in the pathogenesis of infection in preterm infants. Over the past years, a unified theory of infectious diseases emerged, supporting a hypothetical, age-dependent general model of genetic architecture of human infectious diseases. We discuss here how the proposed genetic model can be reconciled with the widely accepted developmental view of early-life infections in humans.UPFELLA
Minimal graphs for 2-factor extension
No full textLet G = (V, E) be a simple loopless finite undirected graph. We say that G is (2-factor) expandable if for any non-edge uv, G + uv has a 2-factor F that contains uv. We are interested in the following: Given a positive integer n = vertical bar V vertical bar, what is the minimum cardinality of E such that there exists G = (V, E) which is 2-factor expandable? This minimum number is denoted by Exp(2)(n). We give an explicit formula for Exp(2)(n) and provide 2-factor expandable graphs of minimum size Exp(2)(n). (C) 2019 Elsevier B.V. All rights reserved.ROS