Subjective Response to the Conditions of Audible Fire Alarm Signals Through a Jury Evaluation Test

Fire Technology - The main purpose of an audible fire alarm signal is to notify occupants of the presence of signs of a fire and to promote escape behavior, such as immediate evacuation. This study...     

Micro-Current Stimulation Has Potential Effects of Hair Growth-Promotion on Human Hair Follicle-Derived Papilla Cells and Animal Model

Recently, a variety of safe and effective non-pharmacological methods have been introduced as new treatments of alopecia. Micro-current electrical stimulation (MCS) is one of them. It is generally known to facilitate cell proliferation and differentiation and promote cell migration and ATP synthesis. This study aimed to investigate the hair growth-promoting effect of MCS on human hair follicle-derived papilla cells (HFDPC) and a telogenic mice model. We examined changes in cell proliferation, migration, and cell cycle progression with MCS-applied HFDPC. The changes of expression of the cell cycle regulatory proteins, molecules related to the PI3K/AKT/mTOR/Fox01 pathway and Wnt/β-catenin pathway were also examined by immunoblotting. Subsequently, we evaluated the various growth factors in developing hair follicles by RT-PCR in MCS-applied (MCS) mice model. From the results, the MCS-applied groups with specific levels showed effects on HFDPC proliferation and migration and promoted cell cycle progression and the expression of cell cycle-related proteins. Moreover, these levels significantly activated the Wnt/β-catenin pathway and PI3K/AKT/mTOR/Fox01 pathway. Various growth factors in developing hair follicles, including Wnts, FGFs, IGF-1, and VEGF-B except for VEGF-A, significantly increased in MCS-applied mice. Our results may confirm that MCS has hair growth-promoting effect on HFDPC as well as telogenic mice model, suggesting a potential treatment strategy for alopecia.     

Host Cell Mimic Polymersomes for Rapid Detection of Highly Pathogenic Influenza Virus via a Viral Fusion and Cell Entry Mechanism

Highly pathogenic avian influenza virus (HPAIV) infections have occurred continuously and crossed the species barrier to humans, leading to fatalities. A polymerase chain reaction based molecular test is currently the most sensitive diagnostic tool for HPAIV; however, the results must be analyzed in centralized diagnosis systems by a trained individual. This requirement leads to delays in quarantine and isolation. To control the spread of HPAIV, rapid and accurate diagnostics suitable for field testing are needed, and the tests must facilitate a differential diagnosis between HPAIV and low pathogenic avian influenza virus (LPAIV), which undergo cleavage specifically by trypsin‐ or furin‐like proteases, respectively. In this study, a differential avian influenza virus rapid test kit is developed and evaluated in vitro and using clinical specimens from HPAIV H5N1‐infected animals. It is demonstrated that this rapid test kit provides highly sensitive and specific detection of HPAIV and LPAIV and is thus a useful field diagnostic tool for H5N1 HPAIV outbreaks and for rapid quarantine control of the disease.     

Reactive Oxygen Species‐Regulating Polymersome as an Antiviral Agent against Influenza Virus

Reactive oxygen species (ROS) produced during mitochondrial oxidative phosphorylation play an important role as signal messengers in the immune system and also regulate signal transduction. ROS production, initiated as a consequence of microbial invasion, if generated at high levels, induces activation of the MEK (mitogen‐activated protein kinase kinase)/ERK (extracellular signal‐regulated kinase) pathway to promote cell survival and proliferation. However, viruses hijack the host cells' pathways, causing biphasic activation of the MEK/ERK cascade. Thus, regulation of ROS leads to concomitant inhibition of virus replication. In the present study, poly(aniline‐co‐pyrrole) polymerized nanoregulators (PASomes) to regulate intracellular ROS levels are synthesized, exploiting their oxidizing‐reducing characteristics. Poly(aniline‐co‐pyrrole) embedded within an amphiphilic methoxy polyethylene glycol‐block‐polyphenylalanine copolymer (mPEG‐b‐pPhe) are used. It is demonstrated that the PASomes are water soluble, biocompatible, and could control ROS levels successfully in vitro, inhibiting viral replication and cell death. Furthermore, the effects of homopolymerized nanoregulators (polypyrrole assembled with mPEG‐b‐pPhe or polyaniline assembled with mPEG‐b‐pPhe) are compared with those of the PASomes. Consequently, it is confirmed that the PASomes can regulate intracellular ROS levels successfully and suppress viral infection, thereby increasing the cell survival rate.     

Relaxed silicon-germanium on insulator substrate by layer transfer

The fabrication of 4 in, relaxed Si_1−xGe_x-on-insulator (SGOI) substrates by layer transfer was demonstrated. A high-quality relaxed Si_1−xGe_x layer was grown using ultrahigh vacuum chemical vapor deposition (UHVCVD) on 4 in. Si donor wafers. Thin Si_−xGe_x film (x=0.2 or 0.25) was then transferred onto an oxidized Si handle wafer by bonding and wafer splitting using hydrogen implantation. The resulting relaxed SGOI structures were characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM).     

Supramolecular‐Assembled Nanoporous Film with Switchable Metal Salts for a Triboelectric Nanogenerator

A triboelectric nanogenerators (TENG) are of great interest as emerging power harvesters because of their simple device architecture with unprecedented high efficiency. Despite the substantial development of new constituent materials and device architectures, a TENG with a switchable surface on a single device, which allows for facile control of the triboelectric output performance, remains a challenge. Here, a supramolecular route for fabricating a novel TENG based on an alkali‐metal‐bound porous film, where the alkali metal ions are readily switched among one another is demonstrated. The soft nanoporous TENG contains numerous SO₃^? groups on the surface of nanopores prepared from the supramolecular assembly of sulfonic‐acid‐terminated polystyrene and poly(2‐vinylpyridine) (P2VP), followed by soft etching of P2VP. Selective binding of alkali metal ions, including Li⁺, Na⁺, K⁺, and Cs⁺, with SO₃^? groups enables the development of mechanically robust alkali‐metal‐ion‐decorated TENGs. The triboelectric output performance of the devices strongly depends on the alkali metal ion species, and the output power ranges from 11.5 to 256.5 µW. This wide‐range triboelectric tuning can be achieved simply by a conventional ion exchange process in a reversible manner, thereby allowing reversible control of the output performance in a single device platform.     

The fabrication of large-area, free-standing GaN by a novel nanoetching process

A simple yet versatile nanoetching process in porosifying and 'machining' GaN is reported in this work. By combining different porosifying conditions through potentiostatic modulation or embedding doping design, we are able to separate and lift off GaN layers over a macroscopic area (≥cm(2)). Strain relaxation and single crystallinity are confirmed by Raman and transmission electron microscopy, respectively. This method is expected to open up a new dimension in epitaxy, design and manufacture of GaN heterostructures and devices.