One-Pot Visual Detection of African Swine Fever Virus Using CRISPR-Cas12a

African swine fever virus (ASFV) is a leading cause of worldwide agricultural loss. ASFV is a highly contagious and lethal disease for both domestic and wild pigs, which has brought enormous economic losses to a number of countries. Conventional methods, such as general polymerase chain reaction and isothermal amplification, are time-consuming, instrument-dependent, and unsatisfactorily accurate. Therefore, rapid, sensitive, and field-deployable detection of ASFV is important for disease surveillance and control. Herein, we created a one-pot visual detection system for ASFV with CRISPR/Cas12a technology combined with LAMP or RPA. A mineral oil sealing strategy was adopted to mitigate sample cross-contamination between parallel vials during high-throughput testing. Furthermore, the blue fluorescence signal produced by ssDNA reporter could be observed by the naked eye without any dedicated instrument. For CRISPR-RPA system, detection could be completed within 40 min with advantageous sensitivity. While CRISPR-LAMP system could complete it within 60 min with a high sensitivity of 5.8 × 102 copies/μl. Furthermore, we verified such detection platforms display no cross-reactivity with other porcine DNA or RNA viruses. Both CRISPR-RPA and CRISPR-LAMP systems permit highly rapid, sensitive, specific, and low-cost Cas12a-mediated visual diagnostic of ASFV for point-of-care testing (POCT) applications

Final Report on ''Advanced Nanocoatings Technology for Manufacturing and Aerospace Applications''

NRC publication: Ye

A Blind Steganalytic Scheme Based on DCT and Spatial Domain for JPEG Images

International audienceUne curatélaire dont la consommation de tabac et d'alcool augmente de manière importante et qui a des comportements alimentaires inadaptés peut voir sa mesure de curatelle simple transformée en curatelle renforcée. En effet, ces comportements entraînent une sévère réduction de ses capacités d'autonomie et caractérisent son inaptitude à percevoir ses revenus et à en faire une utilisation normale, à savoir, une utilisation ne mettant pas manifestement sa santé en danger

Lossless Data Hiding Scheme Using Adjacent Pixel Difference Based on Scan Path

Abstract—This paper presents a reversible data hiding scheme. The proposed scheme is based on the difference histogram shifting to spare space for data hiding. Nine basic scan paths are defined, and this means all-directional adjacent pixel differences can be obtained. Due to the fact that the grayscale values of adjacent pixels are close to each other, the all-directional adjacent pixel difference histogram contains a large number of points with equal values. Hence, more data can be embedded into the cover image than previous works based on histogram shifting. Furthermore, multi-layer embedding is used to increase the hiding capacity. In each embedding process, we can embed a large number of data into the cover image by choosing the best scan path and the optimized pixel difference. As experimental results have shown, the cover images are able to embed secret data at an average 12.5 % of the size of the original images while all the PSNR values of the stego images remain larger than 30 dB. Index Terms—Lossless data hiding, Histogram shifting, Scan path, Multi-layer embedding, Pixel difference I

High-power impulse magnetron sputtering deposition of high crystallinity vanadium dioxide for thermochromic smart windows applications

Vanadium dioxide (VO2) is one of the most promising thermochromic materials for smart windows application because of its ability to modulate infrared radiation (IR) by reversibly transform from semiconductor-like monoclinic VO2 (M) to metallic rutile VO2 (R) above its transition temperature (τc). Despite the promising potential, VO2 has not been commercialized due to various technical difficulties which hinder its feasibilities outside of laboratories environment. One of those is the efficiency of high quality VO2 thin-film fabrication process. In this paper, we presented a method utilizing high-power impulse magnetron sputtering (HiPIMS) to deposit VO2 thin-film on a commercial material such as soda-lime glass substrate with a respectable deposition rate of 5.7 nm/min. The VO2 deposited on soda-lime glass exhibits excellent crystallinity and thermochromic properties (highest luminous transmission Tlum ≈ 30.4%, and solar modulation ΔTsol ≈ 12%) in comparison with similarly prepared VO2 on high temperature glass and quartz substrates. The high crystallinity rendered by short deposition duration and high ionization in HiPIMS process opens opportunities to apply high quality VO2 thin-film onto a variety of substrate more efficiently.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore)Accepted versio

Wear performance of Y-doped nanolayered CrN/AlN coatings

The incorporation of yttrium (Y) in CrAlN based hard coatings has been known to be able to improve the oxidation resistance and thermal stability of these coatings, which is an important characteristic for protective coatings at high temperatures. However, there has been limited information available for the effects of Y doping on the tribological properties of such coatings, especially the wear performance. In this paper, a systematic investigation on the triblogical properties of CrAlN coatings doped with different levels of Y was conducted to correlate the coatings' microstructural, mechanical and tribological properties with their Y contents. The results showed that the wear performance of the coatings decreased with increasing Y doping, though the coatings doped with low to moderate Y contents had comparable wear performance with the pristine CrAlN coating