Efficiency Improvement of HIT Solar Cells on p-Type Si Wafers

Single crystal silicon solar cells are still predominant in the market due to the abundance of silicon on earth and their acceptable efficiency. Different solar-cell structures of single crystalline Si have been investigated to boost efficiency; the heterojunction with intrinsic thin layer (HIT) structure is currently the leading technology. The record efficiency values of state-of-the art HIT solar cells have always been based on n-type single-crystalline Si wafers. Improving the efficiency of cells based on p-type single-crystalline Si wafers could provide broader options for the development of HIT solar cells. In this study, we varied the thickness of intrinsic hydrogenated amorphous Si layer to improve the efficiency of HIT solar cells on p-type Si wafers.     

Melatonin impedes Tet1‐dependent mGluR5 promoter demethylation to relieve pain

Melatonin (N‐acetyl‐5‐methoxytryptamine)/MT2 receptor‐dependent epigenetic modification represents a novel pathway in the treatment of neuropathic pain. Because spinal ten‐eleven translocation methylcytosine dioxygenase 1 (Tet1)‐dependent epigenetic demethylation has recently been linked to pain hypersensitivity, we hypothesized that melatonin/MT2‐dependent analgesia involves spinal Tet1‐dependent demethylation. Here, we showed that spinal Tet1 gene transfer by intrathecal delivery of Tet1‐encoding vectors to naïve rats produced profound and long‐lasting nociceptive hypersensitivity. In addition, enhanced Tet1 expression, Tet1‐metabotropic glutamate receptor subtype 5 (mGluR5) promoter coupling, demethylation at the mGluR5 promoter, and mGluR5 expression in dorsal horn neurons were observed. Rats subjected to spinal nerve ligation and intraplantar complete Freund's adjuvant injection displayed tactile allodynia and behavioral hyperalgesia associated with similar changes in the dorsal horn. Notably, intrathecal melatonin injection reversed the protein expression, protein‐promoter coupling, promoter demethylation, and pain hypersensitivity induced by Tet1 gene transfer, spinal nerve ligation, and intraplantar complete Freund's adjuvant injection. All the effects caused by melatonin were blocked by pretreatment with a MT2 receptor‐selective antagonist. In conclusion, melatonin relieves pain by impeding Tet1‐dependent demethylation of mGluR5 in dorsal horn neurons through the MT2 receptor. Our findings link melatonin/MT2 signaling to Tet1‐dependent epigenetic demethylation of nociceptive genes for the first time and suggest melatonin as a promising therapy for the treatment of pain.