Electronic changes in poly(3,4-ethylenedioxythiophene)-coated LiFeSO4F during electrochemical lithium extraction

The redox activity of tavorite LiFeSO4F coated with poly (3,4-ethylenedioxythiophene), i.e. PEDOT, is investigated by means of several spectroscopic techniques. The electronic changes and iron-ligand redox features of this LiFeSO4F-PEDOT composite are probed upon delithiation through X-ray absorption spectroscopy. The PEDOT coating, which is necessary here to obtain enough electrical conductivity for the electrochemical reactions of LiFeSO4F to occur, is electrochemically stable within the voltage window employed for cell cycling. Although the electronic configuration of PEDOT shows also some changes in correspondence of its reduced and oxidized forms after electrochemical conditioning in Li half-cells, its p-type doping is fully retained between 2.7 and 4.1 V with respect to Li+/Li during the first few cycles. An increased iron-ligand interaction is observed in LixFeSO4F during electrochemical lithium extraction, which appears to be a general trend for polyanionic insertion compounds. This finding is crucial for a deeper understanding of a series of oxidation phenomena in Li-ion battery cathode materials and helps paving the way to the exploration of new energy storage materials with improved electrochemical performances

A genome-wide association study suggests contrasting associations in ACPA-positive versus ACPA-negative rheumatoid arthritis.

BackgroundRheumatoid arthritis (RA) can be divided into two major subsets based on the presence or absence of antibodies to citrullinated peptide antigens (ACPA). Until now, data from genome-wide association studies (GWAS) have only been published from ACPA-positive subsets of RA or from studies that have not separated the two subsets. The aim of the current study is to provide and compare GWAS data for both subsets.Methods and resultsGWAS using the Illumina 300K chip was performed for 774 ACPA-negative patients with RA, 1147 ACPA-positive patients with RA and 1079 controls from the Swedish population-based case-control study EIRA. Imputation was performed which allowed comparisons using 1,723,056 single nucleotide polymorphisms (SNPs). No SNP achieved genome-wide significance (2.9 × 10⁻⁸) in the comparison between ACPA-negative RA and controls. A case-case association study was then performed between ACPA-negative and ACPA-positive RA groups. The major difference in this analysis was in the HLA region where 768 HLA SNPs passed the threshold for genome-wide significance whereas additional contrasting SNPs did not reach genome-wide significance. However, one SNP close to the RPS12P4 locus in chromosome 2 reached a p value of 2 × 10⁶ and this locus can thus be considered as a tentative candidate locus for ACPA-negative RA.ConclusionsACPA-positive and ACPA-negative RA display significant risk allele frequency differences which are mainly confined to the HLA region. The data provide further support for distinct genetic aetiologies of RA subsets and emphasise the need to consider them separately in genetic as well as functional studies of this disease

Mendelian randomization shows a causal effect of low vitamin D on multiple sclerosis risk.

ObjectiveWe sought to estimate the causal effect of low serum 25(OH)D on multiple sclerosis (MS) susceptibility that is not confounded by environmental or lifestyle factors or subject to reverse causality.MethodsWe conducted mendelian randomization (MR) analyses using an instrumental variable (IV) comprising 3 single nucleotide polymorphisms found to be associated with serum 25(OH)D levels at genome-wide significance. We analyzed the effect of the IV on MS risk and both age at onset and disease severity in 2 separate populations using logistic regression models that controlled for sex, year of birth, smoking, education, genetic ancestry, body mass index at age 18-20 years or in 20s, a weighted genetic risk score for 110 known MS-associated variants, and the presence of one or more HLA-DRB1*15:01 alleles.ResultsFindings from MR analyses using the IV showed increasing levels of 25(OH)D are associated with a decreased risk of MS in both populations. In white, non-Hispanic members of Kaiser Permanente Northern California (1,056 MS cases and 9,015 controls), the odds ratio (OR) was 0.79 (p = 0.04, 95% confidence interval (CI): 0.64-0.99). In members of a Swedish population from the Epidemiological Investigation of Multiple Sclerosis and Genes and Environment in Multiple Sclerosis MS case-control studies (6,335 cases and 5,762 controls), the OR was 0.86 (p = 0.03, 95% CI: 0.76-0.98). A meta-analysis of the 2 populations gave a combined OR of 0.85 (p = 0.003, 95% CI: 0.76-0.94). No association was observed for age at onset or disease severity.ConclusionsThese results provide strong evidence that low serum 25(OH)D concentration is a cause of MS, independent of established risk factors

Analysis of Neuropeptide S Receptor Gene (NPSR1) Polymorphism in Rheumatoid Arthritis

Polymorphism in the neuropeptide S receptor gene NPSR1 is associated with asthma and inflammatory bowel disease. NPSR1 is expressed in the brain, where it modulates anxiety and responses to stress, but also in other tissues and cell types including lymphocytes, the lungs, and the intestine, where it appears to be up-regulated in inflammation. We sought to determine whether genetic variability at the NPSR1 locus influences the susceptibility and clinical manifestation of rheumatoid arthritis (RA).From the Epidemiological Investigation of Rheumatoid Arthritis (EIRA) case-control study, 1,888 rheumatoid arthritis patients and 888 controls were genotyped for 19 single-nucleotide polymorphisms (SNPs) spanning the entire NPSR1 gene and 220 KB of DNA on chromosome 7p14. The association between individual genetic markers and their haplotypic combinations, respectively, and diagnosis of RA, presence of autoantibodies to citrullinated proteins (ACPA), and disease activity score based on 28 joints (DAS28) was tested. There was no association between diagnosis of RA and NPSR1 variants. However, several associations of nominal significance were detected concerning susceptibility to ACPA-negative RA and disease activity measures (DAS28). Among these, the association of SNP rs324987 with ACPA-negative RA [(p=0.004, OR=0.674 (95% CI 0.512-0.888)] and that of SNP rs10263447 with DAS28 [p=0.0002, OR=0.380 (95% CI 0.227-0.635)] remained significant after correction for multiple comparisons.NPSR1 polymorphism may be relevant to RA susceptibility and its clinical manifestation. Specific alleles at the NPSR1 locus may represent common risk factors for chronic inflammatory diseases, including RA

Development of a new class of on-skin radio-sensors boosted by thin polymer-based batteries

Conductive polymers are currently collecting interest for the development of low-profile eco-friendly and biocompatible non-metallic batteries capable of providing a local power source for the next-generation flexible body-integrated electronics. In this contribution, we demonstrate the feasibility of an organic ultrathin and multilayered polymer-based battery integrating a radiofrequency identification (RFID) tag antenna by means of an electromagnetic characterization in UHF band of the polymeric films. The optimally modeling of the battery plus the antenna aimed to develop a new class of shape-conformable radio-sensors suitable to adhere to the skin as a tattoo as well as a plaster. A prototype of the device was manufactured and its communication performances were characterized through the measurement of the realized gain of the tag attached directly onto a volunteer's skin

Monitoring and quantifying morphological and structural changes in electrode materials under operando conditions

X-ray absorption and small-angle x-ray scattering spectra were simultaneously acquired under operando conditions in a joined technique approach, for the first time applied in the field of energy storage materials. This approach allows one to closely follow the electronic and local structure evolution, as well as monitor and quantify the morphological and nanostructural changes occurring during electrochemical cycling. Here we demonstrate its potential on the example of doped and non-doped Fe$_2$O$_3$ anode material vs. Li. Our results reveal that upon discharge Fe$^{3+}$ is gradually reduced to the metallic state and segregated as nanoparticles. For the relithiation reaction, upon subsequent charge, we observe improved reversibility for the Sr-doped compared to non-doped and Ca-doped Fe$_2$O$_3$. We highlight that this combined technique approach is a reliable, facile and powerful tool to investigate electrode materials under realistic cycling condition. It provides an unbiased and holistic picture of the morphological and structural changes occurring during operation, which allows for adequate material tailoring

A Tightly Integrated Multilayer Battery Antenna for RFID Epidermal Applications

For the acceptance 1 of biointegrated devices in daily life, radio systems must be developed, which are minimally invasive to the skin, and they must have ultralow-profile local power sources to support data-logging functionality without compromising shape conformability. This contribution proposes a tightly integrated multilayer battery-antenna system (65 × 23 mm2), that is, ultrathin (just 200 ?m), flexible, and lighter than 1 g, making it suitable for epidermal applications. The negative electrode (anode) current collector of the battery is a radio frequency identification tag antenna coated by a conductive polymer (Pedot:PSS) working as anode material. Since the battery is a dynamic device, subjected to discharging, the antenna design must include the variable dielectric properties of the conductive polymer which are here first characterized in the UHF band for real charge/discharge battery conditions. The communication performance of the prototype composite device is hence evaluated through the measurement of the realized gain of the tag antenna (?19.6 dBi at 870 MHz) when it is placed directly onto a volunteer’s forearm. The read range of 1.3–3 m is suitable for occasional data download from the epidermal data logger when the user comes close to a reader-equipped gate

Electrochemical Evaluation of Pb, Ag, and Zn Cyanamides/Carbodiimides

PbNCN, Ag2NCN, and ZnNCN were tested as negative electrode materials for Li-ion batteries. A thorough analysis of the electrochemical mechanism by X-ray diffraction and X-ray absorption spectroscopy showed that, unlike transition metal carbodiimides, these compounds react with lithium via a two-step reaction, starting with conversion followed by alloying. The conversion reaction is highly irreversible for the three compounds, whereas the reversibility of the alloying reaction depends on the metal, that is, highly irreversible for PbNCN and Ag2NCN which contain the cyanamide group (NC−N2−) and more reversible for ZnNCN containing carbodiimide (−NCN−). In the case of the more covalent, cyanamide-type PbNCN and Ag2NCN, the conversion reaction occurs at a higher voltage compared to the more ionic, carbodiimide-type ZnNCN, correlated with the nature of bonding in the NCN group and in the phases themselves. Compared to transition metal carbodiimides, these materials show rather low performance, with no improvement in capacity as it would have been expected from the combination of conversion and alloying