Fast, multicolor photodetection with graphene-contacted p-GaSe/n-InSe van der Waals heterostructures

The integration of different two-dimensional materials within a multilayer van der Waals (vdW) heterostructure offers a promising technology for high performance opto-electronic devices such as photodetectors and light sources. Here we report on the fabrication and electronic properties of vdW heterojunction diodes composed of the direct band gap layered semiconductors InSe and GaSe and transparent monolayer graphene electrodes. We show that the type II band alignment between the two layered materials and their distinctive spectral response, combined with the short channel length and low electrical resistance of graphene electrodes, enable efficient generation and extraction of photoexcited carriers from the heterostructure even when no external voltage is applied. Our devices are fast ( ~ 1 μs), self-driven photodetectors with multicolor photoresponse ranging from the ultraviolet to the near-infrared and offer new routes to miniaturized optoelectronics beyond present semiconductor materials and technologies

Carbon Nanostructure-Based Field-Effect Transistors for Label-Free Chemical/Biological Sensors

Over the past decade, electrical detection of chemical and biological species using novel nanostructure-based devices has attracted significant attention for chemical, genomics, biomedical diagnostics, and drug discovery applications. The use of nanostructured devices in chemical/biological sensors in place of conventional sensing technologies has advantages of high sensitivity, low decreased energy consumption and potentially highly miniaturized integration. Owing to their particular structure, excellent electrical properties and high chemical stability, carbon nanotube and graphene based electrical devices have been widely developed for high performance label-free chemical/biological sensors. Here, we review the latest developments of carbon nanostructure-based transistor sensors in ultrasensitive detection of chemical/biological entities, such as poisonous gases, nucleic acids, proteins and cells

Advances in designs and mechanisms of semiconducting metal oxide nanostructures for high-precision gas sensors operated at room-temperature

High-precision gas sensors operated at room temperature are attractive for various real-time gas monitoring applications, with advantages including low energy consumption, cost effectiveness and device miniaturization/flexibility. Studies on sensing materials, which play a key role in good gas sensing performance, are currently focused extensively on semiconducting metal oxide nanostructures (SMONs) used in the conventional resistance type gas sensors. This topical review highlights the designs and mechanisms of different SMONs with various patterns (e.g. nanoparticles, nanowires, nanosheets, nanorods, nanotubes, nanofilms, etc.) for gas sensors to detect various hazardous gases at room temperature. The key topics include (1) single phase SMONs including both n-type and p-type ones; (2) noble metal nanoparticle and metal ion modified SMONs; (3) composite oxides of SMONs; (4) composites of SMONs with carbon nanomaterials. Enhancement of the sensing performance of SMONs at room temperature can also be realized using a photo-activation effect such as ultraviolet light. SMON based mechanically flexible and wearable room temperature gas sensors are also discussed. Various mechanisms have been discussed for the enhanced sensing performance, which include redox reactions, heterojunction generation, formation of metal sulfides and the spillover effect. Finally, major challenges and prospects for the SMON based room temperature gas sensors are highlighted

Identification of a Glycerophosphocholine Phosphodiesterase, GDE5, in chicken

Glycerophosphodiester phosphodiesterase (GDPD/GDE) catalyzes the hydrolysis of glycerophosphodiesters to glycerol 3-phosphate and alcohol. It was discovered that the glycerophosphodiesterase family plays a role in lipid metabolism and signal pathway in recent years, but little has been known about the characteristics of chicken GDEs. Here, chicken GDE5 (cGDE5) was identified and characterized for the first time. The full length coding cDNA sequence of cGDE5 was cloned, which encoded a polypeptide with 678 amino acids containing a carbohydrate-binding module 20 (CBM20) and a GDPD domain. Tissue expression profiles showed that cGDE5 mRNA was high in various tissues. such as heart, brain, skeletal muscle and testis. Moreover, cGDE5 was demonstrated to exhibit glycerophosphocholine phosphodiesterase activity. These results together suggested that cGDE5, as a unique member of GDE family, may play multiple roles as a cytoplasmic glycerophosphocholine phosphodiesterase

Identification of a Glycerophosphocholine Phosphodiesterase, GDE5, in chicken

Glycerophosphodiester phosphodiesterase (GDPD/GDE) catalyzes the hydrolysis of glycerophosphodiesters to glycerol 3-phosphate and alcohol. It was discovered that the glycerophosphodiesterase family plays a role in lipid metabolism and signal pathway in recent years, but little has been known about the characteristics of chicken GDEs. Here, chicken GDE5 (cGDE5) was identified and characterized for the first time. The full length coding cDNA sequence of cGDE5 was cloned, which encoded a polypeptide with 678 amino acids containing a carbohydrate-binding module 20 (CBM20) and a GDPD domain. Tissue expression profiles showed that cGDE5 mRNA was high in various tissues. such as heart, brain, skeletal muscle and testis. Moreover, cGDE5 was demonstrated to exhibit glycerophosphocholine phosphodiesterase activity. These results together suggested that cGDE5, as a unique member of GDE family, may play multiple roles as a cytoplasmic glycerophosphocholine phosphodiesterase.</jats:p

White Light Transmitting Antenna for Four-spectrum Mobile WDM-VLC

Abstract In this paper, we propose a mixing white light antenna with a homogenizer and an amplification system, and demonstrated its utilization in a four-spectrum mobile VLC. The central element is the homogenizer, which is a square integrating rod that mixes four-spectrum light into white light. Behind it, there are two Fresnel lenses to amplify the light-mixing area. The system is compact with a length of 80 mm and maximal diameter of 58.5 mm. We determined the initial structural parameters of the antenna by theoretical analysis, and then we determine the best parameters by simulation. Simulation results indicate that a 0.75 m×0.75 m area can be illuminated at 1.7 m distance. The detection surface has a high uniformity (76.27%), which can meet illumination and mobile communication requirements simultaneously.</jats:p

PNPLA1-Mediated Acylceramide Biosynthesis and Autosomal Recessive Congenital Ichthyosis

The stratum corneum of the epidermis acts as a life-sustaining permeability barrier. Unique heterogeneous ceramides, especially &omega;-O-acylceramides, are key components for the formation of stable lamellar membrane structures in the stratum corneum and are essential for a vital epidermal permeability barrier. Several enzymes involved in acylceramide synthesis have been demonstrated to be associated with ichthyosis. The function of patatin-like phospholipase domain-containing protein 1 (PNPLA1) was a mystery until the finding that PNPLA1 gene mutations were involved in autosomal-recessive congenital ichthyosis (ARCI) patients, both humans and dogs. PNPLA1 plays an essential role in the biosynthesis of acylceramide as a CoA-independent transacylase. PNPLA1 gene mutations cause decreased acylceramide levels and impaired skin barrier function. More and more mutations in PNPLA1 genes have been identified in recent years. Herein, we describe the structural and functional specificity of PNPLA1, highlight its critical roles in acylceramide synthesis and skin barrier maintenance, and summarize the PNPLA1 mutations currently identified in ARCI patients