Investigation on degradation mechanism of LiNi0.6Co0.2Mn0.2O2 bi-modal cathode materials under the high temperature

Department of Energy Engineering (Energy Engineering)As batteries have been introduced in electric vehicles (EV) and energy storage system (ESS), bi-modal Li[NixCoyMnz] O2 (NCM) cathode materials have been highlighted thanks to their high value of volumetric energy density. However, these commercial applications accompany huge amount of heat release during cycles, therefore, the NCM cathode materials in battery system are rapidly deteriorated by a heat transfer. Therefore, in order to prevent cathode degradation under high temperature, researchers have studied on degradation mechanism of the cathode materials such as phase transition, metal dissolution, cation mixing and intra/intergranular cracks. However, the studies are limited in a microscopic view, which can explain degradation mechanism in a particle scale. In the case of the commercial LiBs, the electrodes with a high thickness are fabricated for achieving high energy density. In this circumstance, the cathode particles are placed in a variety of environment, and particle degradation also unequally occurs according to the particle arrangement. Therefore, investigation on degradation mechanism of the bi-modal NCM cathode should be conducted in a local scale. Herein, ex-situ Raman spectroscopy is utilized as a powerful tool to analysis degradation of bi-modal NCM cathode in a local scale. Correlation with ex-situ Raman spectra and XRD spectra shows that ratio of the Raman peak intensity between 597cm-1(A1g, Ni2+O6) and 547cm-1 (A1g, Ni3+O6) is proper as an indicator of electrode degradation. On the basis of our investigation, the main factor of cathode degradation under high temperature related with the degree of particle fraction and the improvements are discussed in detail.clos

Synthetic biology on acetogenic bacteria for highly efficient conversion of c1 gases to biochemicals

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Synthesis gas, which is mainly produced from fossil fuels or biomass gasification, consists of C1 gases such as carbon monoxide, carbon dioxide, and methane as well as hydrogen. Acetogenic bacteria (acetogens) have emerged as an alternative solution to recycle C1 gases by converting them into value-added biochemicals using the Wood-Ljungdahl pathway. Despite the advantage of utilizing acetogens as biocatalysts, it is difficult to develop industrial-scale bioprocesses because of their slow growth rates and low productivities. To solve these problems, conventional approaches to metabolic engineering have been applied; however, there are several limitations owing to the lack of required genetic bioparts for regulating their metabolic pathways. Recently, synthetic biology based on genetic parts, modules, and circuit design has been actively exploited to overcome the limitations in acetogen engineering. This review covers synthetic biology applications to design and build industrial platform acetogens

Outdoor air pollution and diminished ovarian reserve among infertile Korean women

Background Mounting evidence implicates an association between ambient air pollution and impaired reproductive potential of human. Our study aimed to assess the association between air pollution and ovarian reserve in young, infertile women. Methods Our study included 2276 Korean women who attended a single fertility center in 2016–2018. Womens exposure to air pollution was assessed using concentrations of particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), carbon monoxide (CO), sulfur dioxide (SO2), and ozone (O3) that had been collected at 269 air quality monitoring sites. Exposure estimates were computed for 1, 3, 6, and 12 months prior to the ovarian reserve tests. Anti-Müllerian hormone (AMH) ratio (defined as an observed-to-expected AMH based on age) and low AMH (defined as < 0.5 ng/mL) were employed as indicators of ovarian reserve. We included a clustering effect of 177 districts in generalized estimating equations approach. A secondary analysis was conducted restricting the analyses to Seoul residents to examine the association in highly urbanized setting. Results The mean age was 36.6 ± 4.2 years and AMH level was 3.3 ± 3.1 ng/mL in the study population. Average AMH ratio was 0.8 ± 0.7 and low AMH was observed in 10.3% of women (n=235). The average concentration of six air pollutants was not different between the normal ovarian reserve and low AMH groups for all averaging periods. In multivariable models, an interquartile range (IQR)-increase in 1 month-average PM10 was associated with decrease in AMH ratio among total population (β= −0.06, 95% confidence interval: −0.11, 0.00). When we restrict our analysis to those living in Seoul, IQR-increases in 1 and 12 month-average PM2.5 were associated with 3% (95% CI: −0.07, 0.00) and 10% (95% CI: −0.18, −0.01) decrease in AMH ratio. The ORs per IQR increase in the six air pollutants were close to null in total population and Seoul residents. Conclusions In a cohort of infertile Korean women, there was a suggestive evidence of the negative association between ambient PM concentration and ovarian reserve, highlighting the potential adverse impact of air pollution on womens fertility.This research was supported by the National Research Foundation of Korea funded by the Korean Government. This funding source had no role in study design, in the collection, analysis and interpretation of data, in the writing of the report, and in the decision to submit the article for publication. The contents of this report are solely the responsibility of the authors and do not necessarily represent the official views of the sponsoring organizations

Observation of tW production in the single-lepton channel in pp collisions at root s=13 TeV

A measurement of the cross section of the associated production of a single top quark and a W boson in final states with a muon or electron and jets in proton-proton collisions at root s = 13 TeV is presented. The data correspond to an integrated luminosity of 36 fb(-1) collected with the CMS detector at the CERN LHC in 2016. A boosted decision tree is used to separate the tW signal from the dominant t (t) over bar background, whilst the subleading W+jets and multijet backgrounds are constrained using data-based estimates. This result is the first observation of the tW process in final states containing a muon or electron and jets, with a significance exceeding 5 standard deviations. The cross section is determined to be 89 +/- 4 (stat) +/- 12 (syst) pb, consistent with the standard model.Peer reviewe

Visualization of Tau–Tubulin Interaction in a Living Cell Using Bifluorescence Complementation Technique

Tau is a neuron-specific microtubule-binding protein that stabilizes microtubules. It is generally thought that highly phosphorylated tau dissociates from microtubules and becomes insoluble aggregates, leading to neuronal degeneration. Due to the implication of tau aggregation in neurodegenerative disorders, including Alzheimer&rsquo;s disease, great efforts have been made to identify the tau aggregation process. However, tau interaction with tubulin during the aggregation process remains largely unknown. To scrutinize the tau-tubulin interaction, we generated a cell model that enables visualization of the tau-tubulin interaction in a living cell using the Bifluorescence Complementation (BiFC) Technique. Upon diverse chemical stimulation that induced tau pathology, tau-tubulin BiFC cells showed significantly increased levels of BiFC fluorescence, indicating that tau aggregates together with tubulin. Our results suggest that tubulin should be considered as a key component in the tau aggregation process

Hyaluronate Modified Upconversion Nanoparticles for Near Infrared Light-triggered on-off Tattoo Systems

An in vivo on-off tattoo system was developed using upconversion nanoparticles conjugated with hyaluronate (HA-UCNPs). Two-photon microscopy clearly visualized the transdermal delivery of HA-UCNPs into the deep skin tissue. Upon near-infrared light irradiation, invisible HA-UCNPs in the skin were visualized showing the feasibility as a new on-off tattoo system.111Nsciescopu

Pan-HDAC Inhibitors Promote Tau Aggregation by Increasing the Level of Acetylated Tau

Epigenetic remodeling via histone acetylation has become a popular therapeutic strategy to treat Alzheimer&rsquo;s disease (AD). In particular, histone deacetylase (HDAC) inhibitors including M344 and SAHA have been elucidated to be new drug candidates for AD, improving cognitive abilities impaired in AD mouse models. Although emerged as a promising target for AD, most of the HDAC inhibitors are poorly selective and could cause unwanted side effects. Here we show that tau is one of the cytosolic substrates of HDAC and the treatment of HDAC inhibitors such as Scriptaid, M344, BML281, and SAHA could increase the level of acetylated tau, resulting in the activation of tau pathology