Electrodeposited Cu2Sb as anode material for 3-dimensional Li-ion microbatteries

An increasing demand on high energy and power systems has arisen not only with the development of electric vehicle (EV), hybrid electric vehicle (HEV), telecom, and mobile technologies, but also for specific applications such as powering of microelectronic systems. To power those microdevices, an extra variable is added to the equation: a limited footprint area. Three-dimensional (3D) microbatteries are a solution to combine high-density energy and power. In this work, we present the formation of Cu2Sb onto three-dimensionally architectured arrays of Cu current collectors. Sb electrodeposition conditions and annealing post treatment are discussed in light of their influence on the morphology and battery performances. An increase of cycling stability was observed when Sb was fully alloyed with the Cu current collector. A subsequent separator layer was added to the 3D electrode when optimized. Equivalent capacity values are measured for at least 20 cycles. Work is currently devoted to the identification of the causes of capacity fading

Electrochemical Method for Direct Deposition of Nanometric Bismuth and Its Electrochemical Properties vs Li

We report that nanometric bismuth can directly be electrodeposited at room temperature without the use of a nanoporous template. The morphology, microstructure, and purity of the as-prepared electrodeposits were characterized by scanning electron microscopy, transmission electron microscopy, and infrared spectroscopy. Typically, well-crystallized nanometer-sized particles of Bi ranging from 10 to 20 nm are obtained. The key to success of such a process lies in the electrochemical coreduction of pyrocatechol violet during the bismuth deposition, which disturbs the electrocrystallization process. As a first possible application, we show that Bi/Cu nanoarchitectured electrodes exhibit interesting rate capabilities when used as electrode material vs Li

Electrochemical Deposition and Characterization of Fe₃O₄ Films Produced by the Reduction of Fe(III)-triethanolamine

In this paper, we demonstrate that films of magnetite, Fe3O4, can be deposited by the electrochemical reduction of a Fe(III)-triethanolamine complex in aqueous alkaline solution. the films were deposited with a columnar microstructure and a [100] preferred orientation on stainless steel substrates. In-plane electrical transport and magnetoresistance measurements were performed on the films after they were stripped off onto glass substrates. the resistance of the films was dependent on the oxygen partial pressure. We attribute the increase in resistance in O2 and the decrease in resistance in Ar to the oxidation and reduction of grain boundaries. the decrease in resistance in an Ar atmosphere exhibited first-order kinetics, with an activation energy of 0.2 eV. the temperature dependence of the resistance showed a linear dependence of log(R) versus T-1/2, consistent with tunneling across resistive grain boundaries. a room-temperature magnetoresistance of -6.5% was observed at a magnetic field of 9 T

Experimental and theoretical studies of tetramethoxy-p-benzoquinone: infrared spectra, structural and lithium insertion properties

International audienceIn the search for low-polluting electrode materials for batteries, the use of redox-active organic compounds represents a promising alternative to conventional metal-based systems. In this article we report a combined experimental and theoretical study of tetramethoxy-p-benzoquinone (TMQ). In carbonate-based electrolytes, electrochemical behaviour of this compound is characterized by a reversible insertion process located at approximately 2.85 V vs. Li+/Li0. This relatively high potential reactivity, coupled with our effort to develop computational methodologies in the field of organic electrode materials, prompted us to complement these experimental data with theoretical studies performed using density functional theory (DFT). Single crystals of TMQ were synthesized and thoroughly characterized showing that this quinonic species crystallised in the P21/n space group. The experimental crystal structure of TMQ was then used to assess various DFT methods. The structural features and vibrational spectra were thus predicted by using as a whole five common density functionals (PBE, LDA, revPBE, PBEsol, B3PW91) with and without a semi-empirical correction to account for the van der Waals interactions using either Grimme's (DFT-D2) or Tkatchenko-Scheffler (TS) scheme. The most reliable combination of the DFT functional and the explicit dispersion correction was chosen to study the Li-intercalated molecular crystal (LiTMQ) with the view of indentifying Li insertion sites. A very close agreement with the experiment was found for the average voltage by using the most stable relaxed hypothetical LiTMQ structure. Additionally, a comparison of vibrational spectra gained either for TMQ molecule and its dimer in gas phase or through periodic calculation was undertaken with respect to the experimentally measured infrared spectra. The topological features of the bonds were also investigated in conjunction with estimates of net atomic charges to gain insight into the effect of chemical bonding and intermolecular interaction on Li intercalation. Finally, π-electron delocalization of both quinone and alkali salts of p-semiquinone were determined using the Harmonic Oscillator model of Aromaticity (HOMA) or aromatic fluctuation index (FLU) calculations

Engaging HIV-HCV co-infected patients in HCV treatment: the roles played by the prescribing physician and patients' beliefs (ANRS CO13 HEPAVIH cohort, France)

<p>Abstract</p> <p>Background</p> <p>Treatment for the hepatitis C virus (HCV) may be delayed significantly in HIV/HCV co-infected patients. Our study aims at identifying the correlates of access to HCV treatment in this population.</p> <p>Methods</p> <p>We used 3-year follow-up data from the HEPAVIH ANRS-CO13 nationwide French cohort which enrolled patients living with HIV and HCV. We included pegylated interferon and ribavirin-naive patients (N = 600) at enrolment. Clinical/biological data were retrieved from medical records. Self-administered questionnaires were used for both physicians and their patients to collect data about experience and behaviors, respectively.</p> <p>Results</p> <p>Median [IQR] follow-up was 12[12-24] months and 124 patients (20.7%) had started HCV treatment. After multiple adjustment including patients' negative beliefs about HCV treatment, those followed up by a general practitioner working in a hospital setting were more likely to receive HCV treatment (OR[95%CI]: 1.71 [1.06-2.75]). Patients followed by general practitioners also reported significantly higher levels of alcohol use, severe depressive symptoms and poor social conditions than those followed up by other physicians.</p> <p>Conclusions</p> <p>Hospital-general practitioner networks can play a crucial role in engaging patients who are the most vulnerable and in reducing existing inequities in access to HCV care. Further operational research is needed to assess to what extent these models can be implemented in other settings and for patients who bear the burden of multiple co-morbidities.</p

PLoS One

Compared to the general population, HIV-infected patients are at higher risk of developing non-AIDS-defining cancers. Chronic HCV infection has also been associated with a higher risk than that of the general population of developing cancers other than hepatocarcinoma. Evaluation of the impact of HCV-related factors on non-AIDS-defining and non HCV-liver (NANL) related cancers among HIV/HCV co-infected patients are scarce. The aim of this study was to identify the impact of HIV/HCV clinical characteristics on NANL related cancers in a large cohort of HIV/HCV-coinfected patients followed from 2005 to 2017. Cox proportional hazards models with delayed entry were used to estimate factors associated with NANL related cancer. Among 1391 patients followed for a median of 5 years, 60 patients developed NANL related cancers, yielding an incidence rate of 8.9 per 1000 person-years (95% CI, [6.6-11.1]). By final multivariable analysis, after adjustment for sex, tobacco or alcohol consumption, baseline CD4 cell count and HCV sustained viral response (SVR), age and a longer duration since HIV diagnosis were independently associated with a higher risk of NANL related cancer (aHR for each additional year 1.10, 95% CI 1.06-1.14, p<0.0001 and 1.06, 95% CI 1.01-1.11, p = 0.02, respectively). Duration of HCV infection, cirrhosis, HCV viral load, genotype and SVR were not associated with the occurrence of NANL related cancer. Among HIV/HCV-coinfected patients, age and the duration of HIV infection were the only characteristics found to be associated with the occurrence of NANL related cancer. In contrast, no association was observed with any HCV-related variables

The French national prospective cohort of patients co-infected with HIV and HCV (ANRS CO13 HEPAVIH): Early findings, 2006-2010

<p>Abstract</p> <p>Background</p> <p>In France, it is estimated that 24% of HIV-infected patients are also infected with HCV. Longitudinal studies addressing clinical and public health questions related to HIV-HCV co-infection (HIV-HCV clinical progression and its determinants including genetic dimension, patients' experience with these two diseases and their treatments) are limited. The ANRS CO 13 HEPAVIH cohort was set up to explore these critical questions.</p> <p>To describe the cohort aims and organization, monitoring and data collection procedures, baseline characteristics, as well as follow-up findings to date.</p> <p>Methods</p> <p>Inclusion criteria in the cohort were: age > 18 years, HIV-1 infection, chronic hepatitis C virus (HCV) infection or sustained response to HCV treatment. A standardized medical questionnaire collecting socio-demographic, clinical, biological, therapeutic, histological, ultrasound and endoscopic data is administered at enrolment, then every six months for cirrhotic patients or yearly for non-cirrhotic patients. Also, a self-administered questionnaire documenting socio-behavioral data and adherence to HIV and/or HCV treatments is administered at enrolment and yearly thereafter.</p> <p>Results</p> <p>A total of 1,175 patients were included from January 2006 to December 2008. Their median age at enrolment was 45 years and 70.2% were male. The median CD4 cell count was 442 (IQR: 304-633) cells/μl and HIV RNA plasma viral load was undetectable in 68.8%. Most participants (71.6%) were on HAART. Among the 1,048 HIV-HCV chronically co-infected patients, HCV genotype 1 was predominant (56%) and cirrhosis was present in 25%. As of January, 2010, after a median follow-up of 16.7 months (IQR: 11.3-25.3), 13 new cases of decompensated cirrhosis, nine hepatocellular carcinomas and 20 HCV-related deaths were reported, resulting in a cumulative HCV-related severe event rate of 1.9/100 person-years (95% CI: 1.3-2.5). The rate of HCV-related severe events was higher in cirrhotic patients and those with a low CD4 cells count, but did not differ according to sex, age, alcohol consumption, CDC clinical stage or HCV status.</p> <p>Conclusion</p> <p>The ANRS CO 13 HEPAVIH is a nation-wide cohort using a large network of HIV treatment, infectious diseases and internal medicine clinics in France, and thus is highly representative of the French population living with these two viruses and in care.</p

PLoS One

BACKGROUND: The association between liver stiffness measurements (LSM) and mortality has not been fully described. In particular the effect of LSM on all-cause mortality taking sustained virological response (SVR) into account needs further study. METHODS: HIV/HCV participants in the French nation-wide, prospective, multicenter ANRS CO13 HEPAVIH cohort, with >/=1 LSM by FibroScan (FS) and a detectable HCV RNA when the first valid FS was performed were included. Cox proportional hazards models with delayed entry were performed to determine factors associated with all-cause mortality. LSM and SVR were considered as time dependent covariates. RESULTS: 1,062 patients were included from 2005 to 2015 (69.8% men, median age 45.7 years (IQR 42.4-49.1)). 21.7% had baseline LSM >12.5 kPa. Median follow-up was 4.9 years (IQR 3.2-6.1). 727 (68.5%) were ever treated for HCV: 189 of them (26.0%) achieved SVR. 76 deaths were observed (26 liver-related, 10 HIV-related, 29 non-liver-non-HIV-related, 11 of unknown cause). At the age of 50, the mortality rate was 4.5% for patients with LSM 12.5 kPa. LSM >12.5 kPa (adjusted Hazard Ratio [aHR] = 3.35 [2.06; 5.45], p12.5 kPa was strongly associated with all-cause mortality independently of SVR and other important covariates. Our results suggest that close follow-up of these patients should remain a priority even after achieving SVR

Safety and Efficacy of Dolutegravir in Treatment-Experienced Subjects With Raltegravir-Resistant HIV Type 1 Infection: 24-Week Results of the VIKING Study

Background. Dolutegravir (DTG; S/GSK1349572), a human immunodeficiency virus type 1 (HIV-1) integrase inhibitor, has limited cross-resistance to raltegravir (RAL) and elvitegravir in vitro. This phase IIb study assessed the activity of DTG in HIV-1–infected subjects with genotypic evidence of RAL resistance.Methods. Subjects received DTG 50 mg once daily (cohort I) or 50 mg twice daily (cohort II) while continuing a failing regimen (without RAL) through day 10, after which the background regimen was optimized, when feasible, for cohort I, and at least 1 fully active drug was mandated for cohort II. The primary efficacy end point was the proportion of subjects on day 11 in whom the plasma HIV-1 RNA load decreased by ≥0.7 log10 copies/mL from baseline or was <400 copies/mL.Results. A rapid antiviral response was observed. More subjects achieved the primary end point in cohort II (23 of 24 [96%]), compared with cohort I (21 of 27 [78%]) at day 11. At week 24, 41% and 75% of subjects had an HIV-1 RNA load of <50 copies/mL in cohorts I and II, respectively. Further integrase genotypic evolution was uncommon. Dolutegravir had a good, similar safety profile with each dosing regimen.Conclusion. Dolutegravir 50 mg twice daily with an optimized background provided greater and more durable benefit than the once-daily regimen. These data are the first clinical demonstration of the activity of any integrase inhibitor in subjects with HIV-1 resistant to RAL