A New Method of Gel-Coating Polyethyleneimine (PEI) on Organic Resin Beads. High Capacity and Fast Kinetics of PEI Gel-Coated on Polystyrene

Aqueous redox flow batteries (ARFBs) are a promising technology for large-scale energy storage. Developing high-capacity and long-cycle negolyte materials is one of major challenges for practical ARFBs. Inorganic polysulfide is promising for ARFBs owing to its low cost and high solubility. However, it suffers from severe crossover resulting in low coulombic efficiency and limited lifespan. Organosulfides are more resistant to crossover than polysulfides owing to their bulky structures, but they suffer from slow reaction kinetics. Herein, we report a thiolate negolyte prepared by an exchange reaction between a polysulfide and an organosulfide, preserving low crossover rate of the organosulfide and high reaction kinetics of the polysulfide. The thiolate denoted as 2-hydroxyethyl disulfide+potassium polysulfide (HEDS+K2S2) shows reduced crossover rate than K2S2, faster reaction kinetics than HEDS, and longer lifespan than both HEDS and K2S2. The 1.5 M HEDS+1.5 M K2S2 static cell demonstrated 96 Ah L-1negolyte over 100 and 200 cycles with a high coulombic efficiency of 99.2% and 99.6% at 15 and 25 mA cm-2, respectively. The 0.5 M HEDS+0.5 M K2S2 flow cell delivered a stable and high capacity of 30.7 Ah L-1negolyte over 400 cycles (691 h) at 20 mA cm-2. This study presents an effective strategy to enable low-crossover and fast-kinetics sulfur-based negolytes for advanced ARFBs.

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Abnormal Platelet Serotonin Uptake and Binding Sites in Myeloproliferative Disorders

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661099 ◽

1984 ◽

Vol 51 (03) ◽

pp. 349-353 ◽

Cited By ~ 9

Author(s):

C Caranobe ◽

P Sié ◽

F Fernandez ◽

J Pris ◽

S Moatti ◽

...

Keyword(s):

Binding Sites ◽

High Capacity ◽

Specific Inhibitor ◽

Myeloproliferative Disorders ◽

Normal Subjects ◽

Binding Data ◽

Full Explanation ◽

Number Of Binding Sites ◽

5 Ht Uptake ◽

Kinetics Of

SummaryA simultaneous investigation of the kinetics of serotonin (5 HT) uptake and of binding sites was carried out in the platelets of normal subjects and of 10 patients affected with various types of myeloproliferative disorders (MD). The 5 HT uptake was analysed according to the Lineweaver-Burk and the Eadie-Hofstee methods. With the two methods, the patient’s platelets exhibited a dramatic reduction of the Vi max and of the Km; in some patients the Eadie-Hofstee analysis revealed that a passive diffusion phenomenon is superimposed on the active 5 HT uptake at least for the higher concentration used. The binding data were analysed with the Scatchard method. Two classes of binding sites (high affinity - low capacity, low affinity - high capacity) were found in normal subjects and patients. Pharmacological studies with imipramine, a specific inhibitor of 5 HT uptake, suggested that both the sites are involved in 5 HT uptake. The number of both binding sites was significantly decreased in patient’s platelets while the affinity constants of these binding sites were not significantly reduced in comparison with those of the control subjects. No correlations were found between Vi max, Km and the number of binding sites. These results suggest that a reduction in the number of platelet membrane acceptors for 5 HT commonly occurs in myeloproliferative disorders but does not provide a full explanation of the uptake defect.

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Single atom catalysts supported on N-doped graphene toward fast kinetic Li−S batteries: a theoretical study

Journal of Materials Chemistry A ◽

10.1039/d1ta01948a ◽

2021 ◽

Author(s):

Xu Han ◽

Zeyun Zhang ◽

Xuefei Xu

Keyword(s):

Theoretical Study ◽

Single Atom ◽

Discharge Process ◽

Fast Kinetics ◽

Shuttle Effect ◽

Sufficient Stability ◽

Doped Graphene ◽

Fast Kinetic ◽

Kinetics Of ◽

Charge Discharge

To suppress the shuttle effect of lithium polysulfides and promote fast kinetics of charge−discharge process in Li−S batteries, it is essential to search promising catalysts with sufficient stability and high...

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The poly(ADP-ribose)-dependent chromatin remodeler Alc1 induces local chromatin relaxation upon DNA damage

Molecular Biology of the Cell ◽

10.1091/mbc.e16-05-0269 ◽

2016 ◽

Vol 27 (24) ◽

pp. 3791-3799 ◽

Cited By ~ 56

Author(s):

Hafida Sellou ◽

Théo Lebeaupin ◽

Catherine Chapuis ◽

Rebecca Smith ◽

Anna Hegele ◽

...

Keyword(s):

Dna Damage ◽

Structural Changes ◽

Cellular Responses ◽

Dna Lesions ◽

Fast Kinetics ◽

Important Player ◽

Chromatin Relaxation ◽

Kinetics Of ◽

Laser Microirradiation

Chromatin relaxation is one of the earliest cellular responses to DNA damage. However, what determines these structural changes, including their ATP requirement, is not well understood. Using live-cell imaging and laser microirradiation to induce DNA lesions, we show that the local chromatin relaxation at DNA damage sites is regulated by PARP1 enzymatic activity. We also report that H1 is mobilized at DNA damage sites, but, since this mobilization is largely independent of poly(ADP-ribosyl)ation, it cannot solely explain the chromatin relaxation. Finally, we demonstrate the involvement of Alc1, a poly(ADP-ribose)- and ATP-dependent remodeler, in the chromatin-relaxation process. Deletion of Alc1 impairs chromatin relaxation after DNA damage, while its overexpression strongly enhances relaxation. Altogether our results identify Alc1 as an important player in the fast kinetics of the NAD+- and ATP-dependent chromatin relaxation upon DNA damage in vivo.

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A new method to measure the polymerization shrinkage kinetics of composites using a particle tracking method with computer vision

Dental Materials ◽

10.1016/j.dental.2011.10.005 ◽

2012 ◽

Vol 28 (2) ◽

pp. 212-218 ◽

Cited By ~ 16

Author(s):

In-Bog Lee ◽

Sun-Hong Min ◽

Deog-Gyu Seo

Keyword(s):

Computer Vision ◽

Particle Tracking ◽

New Method ◽

Polymerization Shrinkage ◽

Tracking Method ◽

Particle Tracking Method ◽

Kinetics Of

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Psychomotor stimulant effects of α-pyrrolidinovalerophenone (αPVP) enantiomers correlate with drug binding kinetics at the dopamine transporter

10.21203/rs.3.rs-612345/v1 ◽

2021 ◽

Author(s):

Marco Niello ◽

Spyridon Sideromenos ◽

Ralph Gradisch ◽

Ronan O'Shea ◽

Jakob Schwazer ◽

...

Keyword(s):

Dopamine Transporter ◽

In Silico ◽

Drug Binding ◽

Binding Kinetics ◽

Irreversible Binding ◽

Fast Kinetics ◽

Slow Dissociation ◽

Kinetics Of

Abstract α-Pyrrolidinovalerophenone (αPVP) is a psychostimulant and drug of abuse associated with severe intoxications in humans. αPVP exerts long-lasting psychostimulant effects, when compared to the classical dopamine transporter (DAT) inhibitor cocaine. Here, we compared the two enantiomeric forms of αPVP, the R- and the S-αPVP, with cocaine using a combination of in silico, in vitro and in vivo approaches. We found that αPVP enantiomers substantially differ from cocaine in their binding kinetics. The two enantiomers differ from each other in their association rates. However, they show similar slow dissociation rates leading to pseudo-irreversible binding kinetics at DAT. The pseudo-irreversible binding kinetics of αPVP is responsible for the observed non-competitive pharmacology and it correlates with persistent psychostimulant effects in mice. Thus, the slow binding kinetics of αPVP enantiomers profoundly differ from the fast kinetics of cocaine both in vitro and in vivo, suggesting drug-binding kinetics as a potential driver of psychostimulant effects in vivo.

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Systems analysis of digoxin kinetics and inotropic response in the rat heart: effects of calcium and KB-R7943

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01121.2003 ◽

2004 ◽

Vol 287 (4) ◽

pp. H1857-H1867 ◽

Cited By ~ 7

Author(s):

Michael Weiss ◽

Myoungki Baek ◽

Wonku Kang

Keyword(s):

Rat Heart ◽

Site Response ◽

High Capacity ◽

Left Ventricular ◽

Limiting Factor ◽

Inotropic Response ◽

Influx Rate ◽

High Affinity ◽

Reverse Mode ◽

Kinetics Of

To gain more insight into the mechanistic processes controlling the kinetics of inotropic response of digoxin in the perfused whole heart, an integrated kinetic model was developed incorporating digoxin uptake, receptor binding (Na+-K+-ATPase inhibition), and cellular events linking receptor occupation and response. The model was applied to data obtained in the single-pass Langendorff-perfused rat heart for external [Ca2+] of 0.5 and 1.5 mM under control conditions and in the presence of the reverse-mode Na+/Ca2+ exchange inhibitor KB-R7943 (0.1 μM) in perfusate. Outflow concentration and left ventricular developed pressure data measured for three consecutive doses (15, 30, and 45 μg) in each heart were analyzed simultaneously. While disposition kinetics of digoxin was determined by interaction with a heterogeneous receptor population consisting of a high-affinity/low-capacity and a low-affinity/high- capacity binding site, response generation was >80% mediated by binding to the high-affinity receptor. Digoxin sensitivity increased at lower external [Ca2+] due to higher stimulus amplification. Coadministration of KB-R7943 significantly reduced the positive inotropic effect of digoxin at higher doses (30 and 45 μg) and led to a saturated and delayed receptor occupancy-response relationship in the cellular effectuation model. The results provide further evidence for the functional heterogeneity of the Na+-K+-ATPase and suggest that in the presence of KB-R7943 a reduction of the Ca2+ influx rate via the reverse mode Na+/Ca2+ exchanger might become the limiting factor in digoxin response generation.

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