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Designing high voltage (>3 V) and stable electrochemical supercapacitors with low self‐discharge is desirable for the applications in modern electronic devices. This work demonstrates a 4 V symmetric supercapacitor with stabilized cycling performance through atomic layer deposition (ALD) of alumina (Al2O3) on the surface of activated carbon (AC). The 20‐cycle ALD Al2O3 coated AC delivers 84 % capacitance retention after 1000 charge/discharge cycles under 4 V, contrary to the bare AC cells having only 48 % retention. The extended cycling life is associated with the thickened Stern layer and suppressed oxygen functional group. The self‐discharge data also show that the Al2O3 coating enables AC cells to maintain 53 % of charge retention after 12 h, which is more than twice higher than that of bare AC cells under the same test protocol of 4 V charging. The curve fitting analysis reveals that ALD coating induced slow self‐discharge dominated by ion diffusion mechanism, thus enhancing the AC surface energy., 4 V symmetric supercapacitors are stabilized through optimizing Atomic Layer Deposition of Al2O3 on activated carbon electrodes. The thickened Stern layer and suppressed oxygen functional group extend the cycling life at 4 V. The additional aluminum oxide layer enhances the energy barrier for ion desorption, thereby resulting in a decreased rate of self‐discharge. Too thick oxide coating blocks the nanopores and lower the cycling performance.

The Cover Feature shows the TEM image of activated carbon surface coated with aluminum oxide using the atomic layer deposition technique. The ultra‐thin oxide coating of 5 nm or less is sufficient to stabilize the cycling performance of activated carbon based electric double layer supercapacitor under 4 V through enhanced barrier against ion diffusion in the electrolyte. More information can be found in the Communication by Dayakar Gandla et al. [Image: see text]

All sensory input underlies modulation by endogenous central nervous system pathways. Dysfunctional endogenous pain modulation has been demonstrated in central sensitization and in several pain syndromes, including Irritable Bowel Syndrome (IBS) Activation of endogenous visceral pain modulation by heterotopic stimulation was compared using different methods. Rectal electrical or distension pain alone or with simultaneous (i.e. heterotopic) noxious hand or foot cold stimulation were investigated in randomized sequence in 14 male and 1 female healthy subjects. Mean pain intensities on a visual analogue scale of 0-100 (95% CI) during tonic rectal electrical and distension stimulation alone were 64 (52-76) and 55 (39-71), respectively. Rectal distension pain decreased by 36% (18-55) with simultaneous hand and by 45% (24-66) with simultaneous foot cold pain. Rectal electrical pain decreased by 45% (29-61) during hand and by 46% (28-64) during foot cold pain. Facilitation, i.e. increased rectal pain during heterotopic stimulation was observed in only 1 of 60 stimulation runs. Potent and consistent activation of endogenous visceral pain inhibition was achieved with heterotopic cold pain limb stimulation. Somato-visceral convergence did not affect the effectiveness of induction of endogenous visceral pain inhibition in healthy subjects, as hand and foot heterotopic stimulation resulted in similar pain inhibition. Pain facilitation, as shown earlier in IBS patients, was not evident in healthy controls.

Hydroperoxides and the corresponding peroxy radicals are important intermediates during the partial oxidation of methyl ethyl sulfide (CH3SCH2CH3) in both atmospheric chemistry and in combustion. Structural parameters, internal rotor potentials, bond dissociation energies, and thermochemical properties (ΔHfo, So and Cp(T)) of 3 corresponding hydroperoxides CH2(OOH)SCH2CH3, CH3SCH(OOH)CH3, CH3SCH2CH2OOH of methyl ethyl sulfides, and the radicals formed via loss of a hydrogen atom are important to understanding the oxidation reactions of MES. The lowest energy molecular structures were identified using the density functional B3LYP/6-311G(2d,d,p) level of theory. Standard enthalpies of formation (ΔHfo298) for the radicals and their parent molecules were calculated using the density functional B3LYP/6-31G(d,p), B3LYP/6-31 + G(2d,p), and the composite CBS-QB3 ab initio methods. Isodesmic reactions were used to determine ∆Hfo values. Internal rotation potential energy diagrams and rotation barriers were investigated using the B3LYP/6-31G(d,p) level theory. Contributions for So298 and Cp(T) were calculated using the rigid rotor harmonic oscillator approximation based on the structures and vibrational frequencies obtained by the density functional calculations, with contributions from torsion frequencies replaced by internal rotor contributions. The recommended values for enthalpies of formation of the most stable conformers of CH3SCH2CH2, CH2(OOH)SCH2CH3, CH3SCH(OOH)CH3, and CH3SCH2CH2OOH are −14.0, −33.0, −37.2, and −32.7 kcal/mol, respectively. Group additivity values were developed for estimating properties of structurally similar and larger sulfur-containing peroxides. Groups for use in group additivity estimation of sulfur peroxide thermochemical properties were developed.