Face Biometric Spoof Detection Method Using a Remote Photoplethysmography Signal.

Spoofing attacks in face recognition systems are easy because faces are always exposed. Various remote photoplethysmography-based methods to detect face spoofing have been developed. However, they are vulnerable to replay attacks. In this study, we propose a remote photoplethysmography-based face recognition spoofing detection method that minimizes the susceptibility to certain database dependencies and high-quality replay attacks without additional devices. The proposed method has the following advantages. First, because only an RGB camera is used to detect spoofing attacks, the proposed method is highly usable in various mobile environments. Second, solutions are incorporated in the method to obviate new attack scenarios that have not been previously dealt with. In this study, we propose a remote photoplethysmography-based face recognition spoofing detection method that improves susceptibility to certain database dependencies and high-quality replay attack, which are the limitations of previous methods without additional devices. In the experiment, we also verified the cut-off attack scenario in the jaw and cheek area where the proposed method can be counter-attacked. By using the time series feature and the frequency feature of the remote photoplethysmography signal, it was confirmed that the accuracy of spoof detection was 99.7424%.

Effects of lowest-dose vs. highest-dose pitavastatin on coronary neointimal hyperplasia at 12-month follow-up in type 2 diabetic patients with non-ST elevation acute coronary syndrome: an optical coherence tomography analysis.

Current ACC/AHA guidelines recommend high-dose statin therapy after coronary stenting, especially in diabetic patients; however, pitavastatin 4 mg or pitavastatin 1 mg are frequently used after coronary stenting in Asia, even in patients with acute coronary syndrome. We compared the effects of highest-dose and lowest-dose pitavastatin therapy on coronary neointimal hyperplasia at 12-month follow-up in diabetic patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) using optical coherence tomography. A total of 72 diabetic patients with NSTE-ACS were randomized to lowest-dose pitavastatin [1 mg (n = 36)] or highest-dose pitavastatin [4 mg (n = 36)] after everolimus-eluting stent implantation. The primary endpoint was to compare the normalized neointimal volume at 12-month follow-up. Normalized neointimal volume was significantly lower in the pitavastatin 4 mg group (4.00 ± 2.80 vs. 8.24 ± 2.83 mm3/mm, p < 0.01) at 12-month follow-up. There was also significant difference in neointimal area between the pitavastatin 4 mg group and pitavastatin 1 mg group (0.41 ± 0.28 vs. 0.74 ± 0.23 mm2, p < 0.01). Improvement of brachial artery flow-mediated dilation (baFMD) was significantly higher in the pitavastatin 4 mg group than in pitavastatin 1 mg group (0.15 ± 0.15 vs. - 0.03 ± 0.19 mm, p < 0.001). In addition, the improvement of adiponectin levels was significantly greater in the pitavastatin 4 mg group than in the pitavastatin 1 mg group (2.97 ± 3.98 vs. 0.59 ± 2.80 µg/mL, p < 0.05). Pitavastatin 4 mg significantly improved inflammatory cytokines and lipid profiles compared to pitavastatin 1 mg during the 12-month follow-up, contributing to the reduction of neointimal hyperplasia and to the improvement of baFMD in diabetic patients with NSTE-ACS requiring coronary stenting. Thus, the administration of pitavastatin 4 mg can be safely and effectively used in high-risk patients requiring coronary stenting. Trial registration NCT02545231 (Clinical Trial registration information: https://clinicaltrials.gov/ct2/show/NCT02545231 ).

Anti-freezing-protein type III strongly influences the expression of relevant genes in cryopreserved potato shoot tips.

KEY MESSAGE: AFP improved cryopreservation efficiency of potato (Solanum tuberosum cv. Superior) by regulating transcript levels of CBF1 and DHN1. However, the optimal AFP concentration required for strong induction of the genes was dependent on the type of vitrification solution to which the AFP was added: This finding suggests that AFP increased cryopreservation efficiency by transcriptional regulation of these genes, which might protect plant cell membranes from cold stress during cryopreservation. Despite the availability of many studies reporting the benefits of anti-freeze protein III (AFP III) as a cryoprotectant, the role of AFP III in this process has not been well demonstrated using molecular analysis. In addition, AFP III has not been exploited in the cryopreservation of potato thus far. Therefore, we studied the effects of AFP III on the cryopreservation of potato (Solanum tuberosum cv. Superior). We found that CBF1 and DHN1 genes are low temperature-inducible in potato leaves (S. tuberosum cv. Superior). Transcript levels of these genes expressed in shoot tips cryopreserved with AFP III were higher than those of the controls. However, the optimal AFP III concentration required for strong induction of the genes was dependent on the type of cryoprotection solution to which the AFP III was added: 500 ng/mL worked best for PVS2, while 1500 ng/mL was optimal for LS. Interestingly, the involvement of AFP III in the cryoprotection solutions improved cryopreservation efficiency as compared to the control, and expression levels of the detected genes were associated with cryopreservation efficiency. This finding suggests that AFP III increased cryopreservation efficiency by transcriptional regulation of these genes, which might protect plant cell membranes from cold stress during cryopreservation. Therefore, we expect that our findings will lead to the successful application of AFP III as a potent cryoprotectant in the cryopreservation of rare and commercially important plant germplasms.

A homogeneous atomic layer MoS2(1-x)Se2x alloy prepared by low-pressure chemical vapor deposition, and its properties.

We report the growth of large-area monolayer MoS2(1-x)Se2x alloys with controlled morphologies using a low-pressure chemical vapor deposition (CVD) method. MoS2(1-x)Se2x alloys with different morphologies, created using the same growth time, have been observed by controlling the gaseous MoO3 precursor on substrates placed in regions with different temperatures. TEM observations clearly reveal that the as-synthesized monolayer MoS2(1-x)Se2x alloy is crystalline, with a hexagonal structure. XPS, Raman mapping, and EDS mapping clearly show the homogeneous substitution of ∼2 atomic weight % Se through the whole crystal. Compared with a pristine CVD-grown monolayer of MoS2, the optical band gap differs by 4.52%, from 1.77 eV to 1.69 eV. Additionally, back-gated transistors fabricated on the monolayer MoS2(1-x)Se2x alloy exhibit n-type behavior at a current on/off ratio of ∼104 and a high mobility value of 8.4 cm2 V-1 s-1.

Elimination of chrysanthemum stunt viroid and chrysanthemum chlorotic mottle viroid from infected chrysanthemum by cryopreservation.

Chrysanthemum morifolium 'Borami' and 'Secret Pink' showing symptoms of stunt disease caused by chrysanthemum stunt viroid (CSVd) and 'Yellow Cap' showing chlorotic mottle disease caused by chrysanthemum chlorotic mottle viroid (CChMVd) were confirmed to be infected by the respective viroids by using reverse transcription polymerase chain reaction (RT-PCR). Real-time PCR results showed that the viroid concentrations in the infected cultivars varied between the different regions of origin (Chilgok, Gumi, and Gyeongsan). We applied a cryopreservation protocol for elimination of CSVd from naturally infected 'Borami' collected from Gumi, showing the lowest concentration of CSVd, by varying several factors such as plant vitrification solutions (PVS2 and PVS3), duration of exposure to liquid nitrogen, shoot-tip size, and low-temperature treatment. The solution (PVS2) and low-temperature treatment were found to be critical factors determining the efficacy of viroid elimination. We optimized the protocol by combining of all resulted optimal factors and tested the applicability of the protocol in 'Borami' collected from Chilgok and Gyeongsan and in 'Secret Pink' from Chilgok, Gumi, and Gyeongsan, which displayed different viroid concentrations. We found that the elimination rates varied depending on the cultivar and region of origin. Similar results were observed when the protocol was applied to eliminate CChMVd from the 'Yellow Cap' collected from the same regions. Finally, we found that nested PCR is more reliable for viroid detection than RT-PCR. Overall, cryopreservation can be used to eliminate viroids from infected chrysanthemums; however, the efficacy depends on genotype and initial viroid concentration.

Expression of RsMYB1 in chrysanthemum regulates key anthocyanin biosynthetic genes

Background Several MYB genes belonging to R2R3 MYB transcription factors have been used in several plant species to enhance anthocyanin production, and have shown various expression or regulation patterns. This study focused on the effect of ectopic expression of an RsMYB1 isolated from radish (Raphanus sativa) on chrysanthemum cv. ‘Shinma'. Results The RT-PCR results confirmed that RsMYB1 regulated the expression of three key biosynthetic genes (CmF3H, CmDFR, and CmANS) that are responsible for anthocyanin production in transgenic chrysanthemum, but were not detected in the non-transgenic line. In all transgenic plants, higher expression levels of key biosynthetic genes were observed in flowers than in leaves. However, the presence of RsMYB1 in chrysanthemum did not affect any morphological characteristics, such as plant height, leaf shape or size, and number of flowers. Furthermore, no anthocyanin accumulation was visually observed in the leaves and floral tissue of any of the transgenic lines, which was further confirmed by anthocyanin content estimation. Conclusion To our knowledge, this is the first time the role of an MYB transcription factor in anthocyanin production has been investigated in chrysanthemum.

Layer-controlled CVD growth of large-area two-dimensional MoS2 films.

In spite of the recent heightened interest in molybdenum disulfide (MoS2) as a two-dimensional material with substantial bandgaps and reasonably high carrier mobility, a method for the layer-controlled and large-scale synthesis of high quality MoS2 films has not previously been established. Here, we demonstrate that layer-controlled and large-area CVD MoS2 films can be achieved by treating the surfaces of their bottom SiO2 substrates with the oxygen plasma process. Raman mapping, UV-Vis, and PL mapping are performed to show that mono, bi, and trilayer MoS2 films grown on the plasma treated substrates fully cover the centimeter scale substrates with a uniform thickness. Our TEM images also present the single crystalline nature of the monolayer MoS2 film and the formation of the layer-controlled bi- and tri-layer MoS2 films. Back-gated transistors fabricated on these MoS2 films are found to exhibit the high current on/off ratio of ∼10(6) and high mobility values of 3.6 cm(2) V(-1) s(-1) (monolayer), 8.2 cm(2) V(-1) s(-1) (bilayer), and 15.6 cm(2) V(-1) s(-1) (trilayer). Our results are expected to have a significant impact on further studies of the MoS2 growth mechanism as well as on the scaled layer-controlled production of high quality MoS2 films for a wide range of applications.

Factors influencing in vitro shoot regeneration from leaf segments of Chrysanthemum.

The objective of this research was to develop an efficient protocol for shoot regeneration from leaf segments of the Chrysanthemum cv. Vivid Scarlet by examining the effects of plant growth regulators, dark incubation period, gelling agents, and silver nitrate. The highest number of shoots per explant (12.3) was regenerated from leaf explants cultured on Murashige and Skoog (MS) medium supplemented with a combination of 1 mgL(-1) of 6-benzyladenine (BA) and 2 mgL(-1) of α-naphthaleneacetic acid (NAA) under light conditions without any initial dark period. Gelrite was the most effective gelling agent for shoot regeneration among those tested, whereas the presence of silver nitrate distinctly inhibited shoot regeneration. Superior plant growth and rooting was observed on a hormone-free MS medium solidified with Gelrite. Flow cytometry analysis revealed no ploidy variation between the regenerated plants and the mother plant grown under greenhouse conditions. The established protocol was applicable to shoot regeneration for four out of six cultivars tested. This research will facilitate the genetic transformation and micropropagation of Chrysanthemum cultivars.