Cell-Type Specific Distribution of T-Type Calcium Currents in Lamina II Neurons of the Rat Spinal Cord

Spinal lamina II (substantia gelatinosa, SG) neurons integrate nociceptive information from the primary afferents and are classified according to electrophysiological (tonic firing, delayed firing, single spike, initial burst, phasic firing, gap firing and reluctant firing) or morphological (islet, central, vertical, radial and unclassified) criteria. T-type calcium (Cav3) channels play an essential role in the central mechanism of pathological pain, but the electrophysiological properties and the cell-type specific distribution of T-type channels in SG neurons have not been fully elucidated. To investigate the electrophysiological and morphological features of T-type channel-expressing or -lacking neurons, voltage- and current-clamp recordings were performed on either transverse or parasagittal spinal cord slices. Recording made in transverse spinal cord slices showed that an inward current (IT) was observed in 44.5% of the SG neurons that was fully blocked by Ni2+ and TTA-A2. The amplitude of IT depended on the magnitude and the duration of hyperpolarization pre-pulse. The voltage for eliciting and maximizing IT were −70 mV and −35 mV, respectively. In addition, we found that most of the IT-expressing neurons are tonic firing neurons and exhibit more negative action potential (AP) threshold and smaller difference of AP threshold and resting membrane potential (RMP) than those neurons lacking IT. Consistently, a specific T-type calcium channel blocker TTA-P2 increased the AP threshold and enlarged the difference between AP threshold and membrane potential (Ihold = 0). Meanwhile, the morphological analysis indicated that most of the IT-expressing neurons are islet neurons. In conclusion, we identify a cell-type specific distribution and the function of T-type channels in SG neurons. These findings might provide new insights into the mechanisms underlying the contribution of T-type channels in sensory transmission

Promoting Effect of Layered Titanium Phosphate on the Electrochemical and Photovoltaic Performance of Dye-Sensitized Solar Cells

We reported a composite electrolyte prepared by incorporating layered α-titanium phosphate (α-TiP) into an iodide-based electrolyte using 1-ethyl-3-methylimidazolium tetrafluoroborate(EmimBF4) ionic liquid as solvent. The obtained composite electrolyte exhibited excellent electrochemical and photovoltaic properties compared to pure ionic liquid electrolyte. Both the diffusion coefficient of triiodide (I3−) in the electrolyte and the charge-transfer reaction at the electrode/electrolyte interface were improved markedly. The mechanism for the enhanced electrochemical properties of the composite electrolyte was discussed. The highest conversion efficiency of dye-sensitized solar cell (DSSC) was obtained for the composite electrolyte containing 1wt% α-TiP, with an improvement of 58% in the conversion efficiency than the blank one, which offered a broad prospect for the fabrication of stable DSSCs with a high conversion efficiency

Sapphire-Bonded Photonic Crystal Microcavity Lasers and Their Far-Field Radiation Patterns

Room-temperature continuous-wave lasing was demonstrated in photonic crystal microcavities with diameters of approximately 3.2 μm. Far-field radiation patterns of these lasers were experimentally measured and compared with numerical simulation predictions

(Fe_0.5Ni_0.5)_0.96S with Bimetallic Cation Vacancy Defect as an Efficient Catalyst for Regulating the Reaction Kinetics of Li₂S

Recently, defect-engineered modified materials with abundant active sites are considered promising hosts of sulfur cathodes in lithium sulfur batteries (LSBs). Here, a multifunctional (Fe0.5Ni0.5)0.96S-reduced graphene oxide composite (NFS-rGO) has been fabricated by the combination of highly conductive rGO and bimetallic cation vacancy structure and was utilized as a sulfur host. The bimetallic cation vacancies provide plentiful active sites for the adsorption and accelerated conversion of lithium polysulfides (LiPSs). The rGO afforded a highly conductive network and inhibited the aggregation of (Fe0.5Ni0.5)0.96S nanoparticle. After sulfur loading, the NFS-rGO/S exhibited satisfactory electrochemical performances, and it presented a high capacity of 729.3 mAh g–1 at 3 C and a lower capacity attenuation rate of 0.066% per cycle during 700 cycles at 1 C. In addition, the galvanostatic intermittent titration technique and Li2S deposition results indicated that the nucleation barrier of Li2S is effectively reduced, and the polarization is also alleviated. This work provided a simple preparation technique for the fabrication of bimetallic cation vacancy materials and offered a foundation for application of such materials in LSBs