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A connection between matrix orthogonal polynomials and non-abelian integrable lattices is investigated in this paper. The normalization factors of matrix orthogonal polynomials expressed using quasi-determinants are shown to be the solutions to the non-abelian Toda lattice in semi-discrete and full-discrete cases. Moreover, with a moment modification method, we demonstrate that the Bäcklund transformation of the non-abelian Toda lattice given by Popowicz (1983) is equivalent to the non-abelian Volterra lattice, whose solutions can be expressed using quasi-determinants as well.

Integral imaging (II) display, one of the most critical true-3D display technologies, has received increasing research recently. Significantly, an achromatic metalens array has realized a broadband metalens-array-based II (meta-II). However, the past micro-scale metalens arrays were incompatible with commercial micro-displays; furthermore, the elemental image array (EIA) rendering is always slow. The two hinders in device and algorithm prevent meta-II from being used for practical video-rate near-eye displays (NEDs). This research demonstrates a meta-II NED combining a commercial micro-display and a metalens array. The large-area nanoimprint technology fabricates the metalens array, and a novel real-time rendering algorithm is proposed to generate the EIA. The hardware and software efforts solve the bottlenecks of video-rate meta-II displays. We also build a see-through prototype based on our meta-II NED, demonstrating the feasibility of augmented reality. Our work explores the potential of video-rate meta-II displays, which we expect can be valuable for future virtual and augmented reality.

This paper presents a novel hand-held photometer, termed “Photopette”, for on-spot absorbance measurements of biochemical analytes. The Photopette is a multicomponent, highly portable device with an overall weight of 160 g, which fits within 202 mm × 47 mm × 42 mm. Designed in the form factor of a micropipette, Photopette integrates a photodiode detector with light emitting diodes (LEDs) to form a highly customizable photometer which supports a wide variety of applications within the wavelengths between 260 and 1050 nm. A dual-purpose disposable reflective tip was designed to act as a sample holder and a light-reflecting system, which is in stark contrast to the operation of mainstream spectrophotometers and photometers. Small volume analytes may be measured with low sample loss using this proprietary CuveTip. A user-friendly software application running on smart devices was developed to control and read the values from Photopette via a low-energy Bluetooth link. This one-step strategy allows measurements on-spot without sample transfer, minimizing cross-contamination and human error. The results reported in this paper demonstrate Photopette’s great potential to quantify DNA, direct protein, and cell density directly within the laminar flow hood. Results are compared with a Nanodrop 2000c spectrophotometer, a mainstream spectrophotometer for small-volume measurements.

ABSTRACTThis study focused on the role of methionine (MET) in the autophagy of gastric cancer stem cells (GCSCs) and aims to elaborate its regulatory mechanism.In the present study, the GCSCs were isolated from human gastric cancer cell lines using an anti-CD44 antibody, and then cultured in MET+homocysteine (HCY)−or MET−HCY+medium.In MET+HCY–treated GCSCs, autophagy was suppressed, the methylation and phosphorylation of RAB37 were elevated, and miR-200b expression was down-regulated. Lentiviral vector (LV-) carrying methionine-γ lyase (an enzyme that could specifically lyse MET; Metase) promoted autophagy, reduced the methylation and phosphorylation of RAB37, and up-regulated miR-200b expression in MET+HCY–-treated GCSCs. Then, we found that miR-200b suppressed the expression of protein kinase C α (PKCα), a protein that could inactivate RAB37 through promoting its phosphorylation. LV-Metase down-regulated RAB37 phosphorylation via miR-200b/PKCα, thus promoting the RAB37-mediated autophagy and suppressing cell viability in MET+HCY–treated GCSCs. Finally, the in vivostudy proved that LV-Metase treatment inhibited tumor growth through up-regulating RAB37 expression.In conclusion, MET suppressed RAB37 expression via enhancing its methylation and suppressed RAB37 activity via miR-200b/PKCα axis, thus repressing RAB37-mediated autophagy in GCSCs. The supplementation of Metase lysed MET, thus inducing the autophagy of GCSCs and inhibiting tumor growth.

Mycobacterium tuberculosis (MTB) can cause the terrible tuberculosis (TB), which is reported as one of the most dreadful epidemics. Although many biochemical molecular drugs have been developed to cope with this disease, the drug resistance—especially the multidrug-resistant (MDR) and extensively drug-resistance (XDR)—poses a huge threat to the treatment. However, traditional biochemical experimental method to tackle TB is time-consuming and costly. Benefited by the appearance of the enormous genomic and proteomic sequence data, TB can be treated via sequence-based biological computational approach-bioinformatics. Studies on predicting subcellular localization of mycobacterial protein (MBP) with high precision and efficiency may help figure out the biological function of these proteins and then provide useful insights for protein function annotation as well as drug design. In this review, we reported the progress that has been made in computational prediction of subcellular localization of MBP including the following aspects: 1) Construction of benchmark datasets. 2) Methods of feature extraction. 3) Techniques of feature selection. 4) Application of several published prediction algorithms. 5) The published results. 6) The further study on prediction of subcellular localization of MBP.

MicroRNAs, a group of short non-coding RNA molecules, could regulate gene expression. Many diseases are associated with abnormal expression of miRNAs. Therefore, accurate identification of miRNA precursors is necessary. In the past 10 years, experimental methods, comparative genomics methods, and artificial intelligence methods have been used to identify pre-miRNAs. However, experimental methods and comparative genomics methods have their disadvantages, such as timeconsuming. In contrast, machine learning-based method is a better choice. Therefore, the review summarizes the current advances in pre-miRNA recognition based on computational methods, including the construction of benchmark datasets, feature extraction methods, prediction algorithms, and the results of the models. And we also provide valid information about the predictors currently available. Finally, we give the future perspectives on the identification of pre-miRNAs. The review provides scholars with a whole background of pre-miRNA identification by using machine learning methods, which can help researchers have a clear understanding of progress of the research in this field.

Bioluminescent Proteins (BLPs) are widely distributed in many living organisms that act as a key role of light emission in bioluminescence. Bioluminescence serves various functions in finding food and protecting the organisms from predators. With the routine biotechnological application of bioluminescence, it is recognized to be essential for many medical, commercial and other general technological advances. Therefore, the prediction and characterization of BLPs are significant and can help to explore more secrets about bioluminescence and promote the development of application of bioluminescence. Since the experimental methods are money and time-consuming for BLPs identification, bioinformatics tools have played important role in fast and accurate prediction of BLPs by combining their sequences information with machine learning methods. In this review, we summarized and compared the application of machine learning methods in the prediction of BLPs from different aspects. We wish that this review will provide insights and inspirations for researches on BLPs.

Radiation-induced helium bubbles are detrimental to the mechanical properties of metals, usually causing severe hardening and embrittlement. Hexagonal close-packed (HCP) α-Zr alloys are one of the primary structural materials for nuclear applications, however, the effect of helium bubbles on their deformation and fracture behaviors still remains unexplored. Here, we found that ordered helium bubbles prefer to align along the basal plane in HCP α-Zr. Micro-scale in situ tensile tests revealed that helium bubbles less than 8 nm in size can increase the critical resolved shear stress of the prismatic slip. However, once the helium bubbles are larger than 8 nm, a bubble-softening effect happens due to a decrease in number density of helium bubbles and an increase in porosity. Once the Schmid factor of basal slip is considerably higher than prismatic slip, bubble coalescence along the basal plane becomes the major failure mode in helium-irradiated α-Zr. [ABSTRACT FROM AUTHOR]

In the process of cultivating Rhodobater sphaeroidesR26.1, some of which turned from blue to pink due to the irradiation of a beam of leaking white light. The mutant strains were named ‘pinky’ strains, which were cultivated in the red light and in the dark for a comparative study. It turned out that the strains did not grow in the dark, so they might be photosynthetic bacteria. The electronic absorption spectrum of the ‘pinky’ strains was measured, which shows they contained two main photosynthetic pigments, carotenoids(Cars) and bacteriochlorophylls(BChls). And then they were extracted and analyzed. It proves that Bchls included Bchl a and Bchl a′. Nuclear magnetic resonance (NMR) spectra were exploited to determine the chemical structure of Cars. The results indicate that there were seven kinds of Cars, including lycopene, rhodopin, anhydrorhodovibrin, 3,4-dihydroanhydrorhodovibrin, 3,3,4-dihydrospirilloxanthin, 3,4,3′,4′-tetrahydrospirilloxanthin and spirilloxanthin. Based on the above results, it was found that most identified Cars formed viaspirilloxanthin biosynthesis pathway. The analyzed results of 16S rRNA gene show that the homology of ‘pinky’ strains with Rhodopseudomonas palusteriswas 99%. Rhodopseudomonas palusterishas been cultivated in our laboratory. Because of its strong vitality, it did not become extinct with so many years passing. When Rhodobater sphaeroidesR26.1 was cultivated, it got rejuvenated under the appropriate conditions and caused Rhodobater sphaeroidesR26.1 to be contaminated.

According to the problem of traffic congestion, intelligent vehicle and intelligent transportation system came into being. This paper mainly introduces the development of intelligent vehicle (IV) and intelligent transportation system(ITS), summarizes the active safety system, expounds the research content of ITS, and makes outlook for the development direction of ITS and IV.