Large-scale evolutionary surveillance of the 2009 H1N1 influenza A virus using resequencing arrays

In April 2009, a new influenza A (H1N1 2009) virus emerged that rapidly spread around the world. While current variants of this virus have caused widespread disease, particularly in vulnerable groups, there remains the possibility that future variants may cause increased virulence, drug resistance or vaccine escape. Early detection of these virus variants may offer the chance for increased containment and potentially prevention of the virus spread. We have developed and field-tested a resequencing kit that is capable of interrogating all eight segments of the 2009 influenza A(H1N1) virus genome and its variants, with added focus on critical regions such as drug-binding sites, structural components and mutation hotspots. The accompanying base-calling software (EvolSTAR) introduces novel methods that utilize neighbourhood hybridization intensity profiles and substitution bias of probes on the microarray for mutation confirmation and recovery of ambiguous base queries. Our results demonstrate that EvolSTAR is highly accurate and has a much improved call rate. The high throughput and short turn-around time from sample to sequence and analysis results (30 h for 24 samples) makes this kit an efficient large-scale evolutionary biosurveillance tool

Process Development for Realization of Thin Film Based Perovskite Solar Cells

Perovskite solar cells (PSCs) have been a hot research topic because of their high power conversion efficiency (PCE) reaching ~25%, which is comparable to the commercialized crystalline silicon-based solar cells. There are wide variety of perovskite solar cell (PSC) architectures, material sets and fabrication techniques that could be employed. However, in order to enable the commercial productions of the most cost-effective PSC devices, a simple device architecture along with easy fabrication procedures are required. Here we report the preliminary experiments that have been conducted to develop the processes for realization of thin film based PSCs

A novel simplified approach in fabricating TiO2 photoanodes for dye-sensitized solar cells

Globally, the hydrothermal method is widely adopted in synthesizing TiO2 photoanodes for various applications, including dye-sensitized solar cells (DSSCs). Nonetheless, this method typically involves several synthesis steps, and most reported works were intricate and complex to follow. In this work, a reinvented novel methodology for hydrothermal synthesis was successfully developed. The mixed-phase of anatase-rutile TiO2 photoanodes was demonstrated by omitting several intermediate hydrothermal steps. Using the reinvented methodology, the DSSC devices presented a comparable and excellent power conversion efficiency (η = 3.30%) to commercial TiO2-based DSSCs (η = 3.81%). Hence, this preliminary study provided new perspectives toward simplifying wet chemical synthesis TiO2 techniques for the design structure of DSSCs

Hydrothermal duration effect on the self-assembled TiO2 photo-anode for DSSC application

Dye-sensitized solar cell (DSSC) has been extensively researched over the past few decades due to its facile and low-cost fabrication process compared to the silicon solar cell. Generally, the photo-anode of the DSSC consists of a titanium dioxide (TiO2) film deposited on a transparent conducting oxide (TCO) substrate. Hydrothermal method is the most widely adopted technique for the synthesis of TiO2 photo-anode. Nevertheless, the optimum hydrothermal synthesis parameters have yet to be elucidated. In this work, the influences of hydrothermal duration on the self-assembled TiO2 photo-anode were investigated. It was discovered that the rutile content in the TiO2 photo-anodes can be controlled by adjusting the hydrothermal durations. The highest DSSC efficiency of 3.88% was achieved at an optimum hydrothermal duration of 10 h, corresponding to a rutile content of 80.43%. The improvement in DSSC efficiency can be ascribed to the reduced electron-hole recombination resulting from electron transfer from rutile to anatase lattice trapping sites, thereby improving the photocurrent. However, when the hydrothermal durations exceeded 10 h, the DSSC efficiency dropped due to the agglomeration of the rutile TiO2 resulted from excessive rutile content, which led to decreased surface area for dye adsorption and hence lower photocurrent. The results suggest the importance of controlling the hydrothermal duration on the synthesis of TiO2 photo-anode

A Green Approach to Natural Dyes in Dye-Sensitized Solar Cells

Solar cells are pivotal in harnessing renewable energy for a greener and more sustainable energy landscape. Nonetheless, eco-friendly materials for solar cells have not been as extensive as conventional counterparts, highlighting a significant area for further investigation in advanc�ing sustainable energy technologies. This study investigated natural dyes from cost-effective and environmentally friendly blueberries and mulberries. These dyes were utilized as alternative sen�sitizers for dye-sensitized solar cells (DSSCs). Alongside the natural dyes, a green approach was adopted for the DSSC design, encompassing TiO2 photoanodes, eco-friendly electrolytes, and green counter-electrodes created from graphite pencils and candle soot. Consequently, the best-optimized dye sensitizer was mulberry, with an output power of 13.79 µW and 0.122 µW for outdoor and indoor environments, respectively. This study underscored the feasibility of integrating DSSCs with sensitizers derived from readily available food ingredients, potentially expanding their applications in educational kits and technology development initiatives

Electrochromic Properties of Sol-Gel Deposited Electrochromic TiO2 Thin Films

Electrochromic (EC) smart windows are a type of glass window that can change from transparent to darker colour shades when a small voltage is applied. Titanium dioxide (TiO2) can be utilised as an EC material for EC smart windows. Although the TiO2 sol-gel spin-coating method is commonly used, the effect of the number of TiO2 layers was not reported. Thus, this paper investigates the effect of the number of TiO2layers. The increasing number of TiO2film layers demonstrated a noticeable increase in the thin films ‘anodic and cathodic diffusion coefficient, particularly with 11 TiO2layers. Additionally, the colouration and bleaching time was revealed to have a low correlation as the number of layers increased. Nonetheless, the lower number of TiO2layers resulted in lower colouring transmittance. Comparatively, the colouration efficiency for all films did not exhibit any significant change. Hence this study on the effect of the TiO2layering technique can open a new pathway in understanding the EC properties of TiO2-based EC devices

Performances of Polymer-Dispersed Liquid Crystal Films for Smart Glass Applications

Polymer-dispersed liquid crystal (PDLC) film is an active smart film penetrating the market due to its unique functionalities. These functional characteristics include switchable tint capabilities, which shield building residents from the sun’s harmful ultraviolet (UV) rays, improve energy-saving features, and produce higher cost-efficiency. Although PDLC films are promising in several applications, there is still ambiguity on the performance of PDLC films. Particularly, the sizing effects’ (such as film thickness and area) correlation with visible light transmission (VLT), ultraviolet rejection (UVR), infrared rejection (IRR), light intensity, current consumption, and apparent power consumption is not well understood. Therefore, this study investigated the sizing effects of PDLC films, including the thickness effect on VLT, UVR, IRR, light intensity, and area influence on current and apparent power consumptions. The varying applied voltage effect on the light transmittance of the PDLC film was also effectively demonstrated. A 0.1 mm PDLC film was successfully presented as a cost-efficient film with optimal parameters. Consequently, this study paves the way for a clearer understanding of PDLC films (behavior and sizing effects) in implementing economic PDLC films for large-scale adoption in commercial and residential premises

Recent Advances in Halide Perovskite Resistive Switching Memory Devices: A Transformation from Lead-Based to Lead-Free Perovskites

Due to their remarkable electrical and light absorption characteristics, hybrid organic–inorganic perovskites have recently gained popularity in several applications such as optoelectronics, lasers, and light-emitting diodes. Through this, there has recently been an increase in the use of halide perovskites (HPs) in resistive switching (RS) devices. However, lead-based (Pb-based) perovskites are notorious for being unstable and harmful to the environment. As a result, lead-free (Pb-free) perovskite alternatives are being investigated in achieving the long-term and sustainable use of RS devices. This work describes the characteristics of Pb-based and Pb-free perovskite RS devices. It also presents the recent advancements of HP RS devices, including the selection strategies of perovskite structures. In terms of resistive qualities, the directions of both HPs appear to be identical. Following that, the possible impact of switching from Pb-based to Pb-free HPs is examined to determine the requirement in RS devices. Finally, this work discusses the opportunities and challenges of HP RS devices in creating a stable, efficient, and sustainable memory storage technology