Janus-faced, multifunctional separator membranes for high-performance lithium-ion batteries

Department of Energy Engineering(Battery Science and Technology)A vigorous expansion of newly emerging application fields, including smart mobile electronics, power tools, (hybrid) electric vehicles, and grid-scale energy storage systems inspires the relentless pursuit of advanced rechargeable power sources with reliable/sustainable electrochemical performance and safety tolerance. Among the numerous power sources, undoubtedly, lithium-ion batteries (LIBs) are listed in the top tier and still garner considerable attention as an appealing electrochemical system to address the challenging issues. A battery separator membrane is supposed to be electrically inert for preventing electrical contact (resulting in safety failures) between electrodes, in addition to its another key role as an ion-conducting route. Here, as a multifunctional membrane strategy to break up the stereotypical belief about battery separators, we demonstrate a new class of Janus-faced, dual (ion/electron)-conductive/chemically-active (i.e., heavy metal ion-chelating) battery separators based on elaborately-designed heterolayered nanomat architecture. The Janus-faced, heterolayered nanomat separators (referred to as “Janus separators”) are fabricated through the in-series, concurrent electrospraying/electrospinning process. The Janus separator is composed of an ion-conductive/metal ion-chelating support layer (= a mat of densely-packed, thiol-functionalized silica particles spatially besieged by polyvinylpyrrolidone (PVP)/polyacrylonitrile (PAN) nanofibers) and a dual-conductive top layer (= a thin mat of polyetherimide (PEI) nanofibers wrapped with multi-walled carbon nanotubes (MWNTs)). The support layer acts as a chemical trap that can capture heavy metal ions dissolved in liquid electrolytes and the thin top layer serves as an upper current collector of cathodes to facilitate redox reaction kinetics. Notably, the unusual porous structure (specifically, preferential deposition of the MWNTs along the PEI nanofibers) of the top layer is theoretically elucidated using molecular dynamics simulation. As a consequence, the Janus separator enables significant improvements in the fast-rate charge/discharge reaction of lithium-ion batteries and also high-temperature cycling performance, which lie far beyond those achievable with conventional polyethylene separators. The Janus separator featuring such exceptional multifunctionality is envisioned to open a new membrane solution for high-energy/high-performance lithium-ion batteries that will power forthcoming smart ubiquitous era.ope

Predictors of intentional intoxication using decision tree modeling analysis: a retrospective study

Objective The suicide rate in South Korea is very high and is expected to increase in coming years. Intoxication is the most common suicide attempt method as well as one of the common reason for presenting to an emergency medical center. We used decision tree modeling analysis to identify predictors of risk for suicide by intentional intoxication. Methods A single-center, retrospective study was conducted at our hospital using a 4-year registry of the institute from January 1, 2013 to December 31, 2016. Demographic factors, such as sex, age, intentionality, therapeutic adherence, alcohol consumption, smoking status, physical disease, cancer, psychiatric disease, and toxicological factors, such as type of intoxicant and poisoning severity score were collected. Candidate risk factors based on the decision tree were used to select variables for multiple logistic regression analysis. Results In total, 4,023 patients with intoxication were enrolled as study participants, with 2,247 (55.9%) identified as cases of intentional intoxication. Reported annual percentages of intentional intoxication among patients were 628/937 (67.0%), 608/1,082 (56.2%), 536/1,017 (52.7), 475/987 (48.1%) from 2013 to 2016. Significant predictors identified based on decision tree analysis were alcohol consumption, old age, psychiatric disease, smoking, and male sex; those identified based on multiple regression analysis were alcohol consumption, smoking, male sex, psychiatric disease, old age, poor therapeutic adherence, and physical disease. Conclusion We identified important predictors of suicide risk by intentional intoxication. A specific and realistic approach to analysis using the decision tree modeling technique is an effective method to determine those groups at risk of suicide by intentional intoxication

Activation of Protein Kinase G After Repeated Cocaine Administration Is Necessary for the Phosphorylation of α-Amino-3-Hydroxy-5-Methyl-4-Isoxazolepropionic Acid Receptor GluA1 at Serine 831 in the Rat Nucleus Accumbens

Phosphorylation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in the striatum plays a crucial role in regulating the receptor-coupled signaling cascades leading to behavioral changes associated with psychostimulant exposure. The present study determined if activation of protein kinase G (PKG) contributes to the phosphorylation of AMPA receptor GluA1 subunit at the position of serine 831 (GluA1-S831) in the rat nucleus accumbens (NAc) after repeated cocaine administration. The results demonstrated that repeated intraperitoneal (i.p.) injections of cocaine (20 mg/kg) once a day for seven consecutive days significantly increased the level of phosphorylated (p)GluA1-S831. This increase was decreased by the intra-NAc infusion of either the cyclic guanosine monophosphate (cGMP) analog, Rp-8-Br-PET-cGMPS (5 nmol/1 μL), or the PKG inhibitor, KT5823 (2 nmol/1 μL). Repeated cocaine administration increased PKG binding activity to GluA1. This increase in GluA1-S831 phosphorylation after repeated cocaine administration was decreased by the intra-NAc infusion of the synthetic peptide (Tat-tagged interfering peptide (Tat-GluA1-i)), that interferes with the binding of PKG to GluA1. Intra-NAc infusion of the interfering peptide also reduced the repeated cocaine-induced increase in locomotor activity. These findings suggest that activated PKG, after repeated exposure to cocaine, binds to AMPA receptor GluA1 and is required for the phosphorylation of S831, contributing to behavioral changes

bending resistance and cyclic fatigue resistance of waveone gold reciproc blue and hyflex edm instruments

Abstract Background/purpose Several single-file systems manufactured using different heat treatment and operated by different kinematics have been released. This study compared the bending resistance and cyclic fatigue resistance of three NiTi files, and examined their phase-transformation behavior. Materials and methods WaveOne Gold Primary (WOG), Reciproc Blue R25 (RPB), and HyFlex EDM OneFile (HDM) were tested (N = 40/instrument). A vertical load was applied to a point 3 mm from the tip, and the stress was measured until a displacement of 3 mm. Tests were conducted at either room temperature (RT: 22 °C) or body temperature (BT: 37 °C) (n = 10). Cyclic fatigue resistance tests were performed in an artificial canal, which had a curvature angle of 40° and a 5-mm radius. Tests were conducted at either RT or BT (n = 10). Instruments were operated according to the manufacturers' instructions. Test results were analyzed using the Kruskal–Wallis and the Mann–Whitney tests. Additional three instruments of each brand were subjected to differential scanning calorimetry (DSC). Results At RT the bending resistance of three files were not significantly different. However, at BT the bending resistance of RPB was highest, followed by WOG, and HDM (P  Conclusion HDM presented superior flexibility and cyclic fatigue resistance at BT

Explaining the continuum of social participation among older adults in Singapore: from 'closed doors' to active ageing in multi-ethnic community settings.

OBJECTIVES: This study aims to identify and explain the continuum in which older people in Singapore participate in community and social life, highlighting the influence of culture and policy context on social participation. METHODS: Using an ethnographic approach in a neighbourhood (n=109), we conducted focus groups with older adults of different ethnicities, exploring experiences of social participation. Next, participants took 50 photographs relating to 'lives of elders', showcasing the socio-ecological context that influenced social participation. Lastly, go-along interviews were conducted in various precincts with community leaders. RESULTS: A continuum of social participation emerged among older adults, ranging from (1) marginalization and exclusion, to (2) 'comfort-zoning' alone (3) seeking consistent social interactions, (4) expansion of social network, and (5) giving back to society. Seeking consistent social interactions was shaped by a preference for cultural grouping and ethnic values, but also a desire for emotional safety. Attitudes about expanding one's social network depended on the psychosocial adjustment of the older person to the prospect of gossip and 'trouble' of managing social relations. Despite the societal desirability of an active ageing lifestyle, cultural scripts emphasizing family meant older adults organized participation in social and community life, around family responsibilities. Institutionalizing family reliance in Singapore's welfare approach penalized lower-income older adults with little family support from accessing subsidies, and left some living on the margins. DISCUSSION: To promote inclusiveness, ageing programs should address preferences for social participation, overcoming barriers at the individual, ethnic culture and policy level

Zanthoxylum ailanthoides

Zanthoxylum ailanthoides (ZA) has been used as folk medicines in East Asian and recently reported to have several bioactivity; however, the studies of ZA on the regulation of triacylglycerol (TG) biosynthesis have not been elucidated yet. In this study, we examined whether the methanol extract of ZA (ZA-M) could reduce oleic acid- (OA-) induced intracellular lipid accumulation and confirmed its mode of action in HepG2 cells. ZA-M was shown to promote the phosphorylation of AMPK and its upstream LKB1, followed by reduction of lipogenic gene expressions. As a result, treatment of ZA-M blocked de novo TG biosynthesis and subsequently mitigated intracellular neutral lipid accumulation in HepG2 cells. ZA-M also inhibited OA-induced production of reactive oxygen species (ROS) and TNF-α, suggesting that ZA-M possess the anti-inflammatory feature in fatty acid over accumulated condition. Taken together, these results suggest that ZA-M attenuates OA-induced lipid accumulation and inflammation through the activation of LKB1/AMPK signaling pathway in HepG2 cells

Does Diabetes Mellitus Influence Standardized Uptake Values of Fluorodeoxyglucose Positron Emission Tomography in Colorectal Cancer?

Background/AimsHyperglycemia is associated with decreased 2-18[F]fluoro-2-deoxy-D-glucose (FDG) uptake by tumors assessed by positron emission tomography (PET). In this retrospective study we investigated a comparison of standardized uptake values (SUVs) in patients with primary colorectal cancers who either had diabetes mellitus (DM) or were otherwise healthy.MethodsThe medical records of 397 patients who were diagnosed with colorectal cancer and underwent PET-CT between January 2006 and December 2012 were analyzed. Eighty patients with DM and 317 patients without DM were included. Clinical characteristics were reviewed and maximal standardized uptake values (SUVmax) were calculated in the primary colorectal lesions.ResultsThere was no significant difference between tumor SUVmax in DM patients (10.60±5.78) and those without DM (10.92±5.44). In addition, no significant difference was detected between tumor SUVmax in DM patients with glycated hemoglobin (HbA1c) levels <8% (10.34±5.17) and those with HbA1c levels ≥8% (10.61±7.27). The maximum size of the primary colorectal tumor was associated with SUVmax in a linear regression analysis.ConclusionThe results of this study showed that DM did not influence FDG uptake values in colorectal cancer patients regardless of glucose levels