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This paper proposes a proof‐of‐concept design for RIS made with liquid crystals (LC) and Corning glass for wireless communication applications. The proposed RIS concept consists of the specially designed copper‐coated glass substrates and liquid crystal materials that were filled in between two glass substrates. The LC layer exists between the upper and lower Corning glass sheets, and it is 20 μm thick. Although the 20 μm cell‐gap is very thin compared to the operating frequency (it is more than 100 μm in previous research), more than the 180° phase difference was achieved by applying 10 V in the designed frequency band. Our proposed concept can improve wireless communication coverage by reflecting incident electromagnetic waves in the desired direction to secure a propagation path by simply changing the alignment of LC molecules under different driving voltages. Also, conventional LCD manufacturing technology can significantly reduce costs and support larger sized capabilities, compared to incumbent semiconductor‐based electronics and printed circuit board (PCB) processing. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of perovskite solar cells (PSCs) has been renewed annually, now recorded to 25.7%, which is the highest efficiency for thin‐film solar cells, raising expectations for commercialization. However, the PSCs have a massive technical lack in entering the photovoltaic industry because of the low PCE of perovskite solar modules (PSMs), poor stability, high levelized cost of energy (LCOE), and environmental issues. Herein, cutting‐edge studies for overcoming the challenges faced by commercialization of PSCs are discussed. First, the reduction of the efficiency gap between small‐area PSCs and the large‐area PSMs via the solution process is reviewed. Second, the strategies for stable PSMs are discussed to reduce the LCOE. In addition, the environmental issues for manufacturing and sustainable use of PSMs are dealt with and it is demonstrated that the recycling/reuse of PSMs is the most promising way to reduce the manufacturing costs. Finally, it is suggested that the life cycle assessment system from manufacturing to recycling/reuse for PSMs is the key technology to resolve the commercialization issues of PSCs. [ABSTRACT FROM AUTHOR]

Background: Melatonin is a multifunctional hormone synthesized in the pineal gland and peripheral reproductive tissues that regulates many biological processes. There is increasing evidence for a role of melatonin in oocyte maturation and embryonic development in various mammals. However, no study has reported evidence for the existence of melatonergic system, such as melatonin synthesis enzymes, melatonin membrane receptors, or melatonin binding sites in non‐human primate cumulus–oocyte complexes (COCs). Methods: Reverse transcription polymerase chain reaction (RT‐PCR) and immunocytochemistry were performed to detect transcripts and proteins of the rate‐limiting enzyme in melatonin synthesis (arylalkylamine N‐acetyltransferase, AANAT), melatonin membrane receptors (MT1 and MT2), and a melatonin binding site (NRH: quinone oxidoreductase 2, NQO2) in cynomolgus monkey COCs. Results: RT‐PCR analyses revealed the presence of AANAT, MT1, MT2, and NQO2 transcripts in granulosa cells, germinal vesicle (GV)‐ and metaphase II (MII)‐stage cumulus cells, and oocytes. Immunocytochemistry revealed the presence of AANAT, MT1, MT2, and NQO2 proteins in GV‐ and MII‐stage COCs. Conclusions: Our results provide the first evidence for the existence of the rate‐limiting enzyme required for melatonin synthesis, melatonin membrane receptors, and a melatonin binding site in non‐human primate COCs. [ABSTRACT FROM AUTHOR]