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Analysis of the heavy fractions in crude oil has been important in petroleum industries. It is well known that heavy fractions such as vacuum gas oils (VGOs) include heteroatoms, of which sulfur and nitrogen are often characterized in many cases. We conducted research regarding the molecular species analysis of VGOs. Further refine processes using VGOs are becoming important when considering carbon recycling. In this work, we attempted to classify compounds within VGOs provided by Kuwait Institute for Scientific Research. Two VGOs were priorly distillated from Kuwait Export crude and Lower Fars crude. Quantitative analysis was performed mainly using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOFMS). MALDI-TOF-MS has been developed for analyzing high-molecular-weight compounds such as polymer and biopolymers. As matrix selection is one of the most important aspects in MALDI-TOFMS, the careful selection of a matrix was firstly evaluated, followed by analysis using a Kendrick plot with nominal mass series (z*). The objective was to evaluate if this work could provide an effective classification of VGOs compounds. The Kendrick plot is a well-known method for processing mass data. The difference in the Kendrick mass defect (KMD) between CnH2n−14S and CnH2n−20O is only 0.0005 mass units, which makes it difficult in general to distinguish these compounds. However, since the z* value showed effective differences during the classification of these compounds, qualitative analysis could be possible. The analysis using nominal mass series showed the potential to be used as an effective method in analyzing heavy fractions. [ABSTRACT FROM AUTHOR]

Two disruptive space telescope concepts are being designed and developed at the University of Arizona; these are the 20-meter OASIS (Orbiting Astronomical Satellite for Investigating Stellar Systems) and 8.5-meter Nautilus. OASIS combines break-through inflatable aperture and adaptive optics techniques to realize the dream of a 20+ meter class spaceborne terahertz/far-infrared telescope. In the Nautilus visible/near-infrared telescope concept, conventional primary mirrors are replaced by an ~8.5-meter MODE (Multi-order diffractive engineered) lens with 10 times lower areal density and up to 100 times lower mis-alignment sensitivity over traditional systems, enabling large-diameter optical space telescopes. The OASIS and Nautilus concepts have the potential to greatly reduce mission costs and risks compared to the current state of the art.

A catadioptric wide-angle lens having a rectilinear projection scheme has been developed with a view to possible applications in the security-surveillance area. The lens has been designed for a miniature camera with a video graphics array-grade 1/3 in. color CCD sensor. The field of view of the lens is over 151[degrees], and still distortion is under 1%. Furthermore, the modulation transfer function is better than 0.3 at 70 line pairs/mm over the whole active area of the image sensor. OCIS codes: 080.3620, 110.5200, 220.1250, 220.2740.

A new formula for a catadioptric panoramic lens with an equidistance projection scheme has been derived. The fabricated lens has a field of view that is wider than that of any previously reported panoramic lens, and the nonimaged region near the back of the camera has a constant volume with zero angular extension. OCIS codes: 080.3620, 120.4640, 220.2740.

Polycyclic aromatic hydrocarbons (PAHs) are produced during incomplete combustion of organic matter. Many of them are likely to be carcinogenic and cause mutations. In this study, the PAH4 (benzo[a]pyrene (BaP), benz[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbF)) content in deep-fat fried pork was evaluated according to temperature and time, and a risk assessment was conducted. The high performance liquid chromatography-fluorescence detection (HPLC-FLD) method for PAH4 analysis was validated by determining linearity (R2), recovery, limit of detection (LOD), and limit of quantitation (LOQ). The linearity was R2 ≥ 0.99. The PAH4 level was dependent on the temperature, time, and nature of the edible oil. Before heat treatment, the PAH4 content of pork was 0.38 μg/kg. The PAH4 content of deep-fat fried pork ranged from 0.86 to 6.86 μg/kg according to temperature (160, 180, 200 °C) and time (3, 6, 9 min). Exposure to PAH4 via the consumption of deep-fat fried pork for different age groups among the Korean population was 0.01–0.89 μg-TEQBaP/kg/day, with the margin of exposure calculated as 7.88 × 104–5.22 × 106. The PAH4 content and risk of exposure increased proportionally with the heat treatment temperature and time. The survey provided important information in terms of evaluating the health risks that PAH compounds can cause in people's diets due to the heat treatment of pork. [ABSTRACT FROM AUTHOR]

Here, we report a bienzymatic cascade to produce β‐amino acids as an intermediate for the synthesis of the leading oral antidiabetic drug, sitagliptin. A whole‐cell biotransformation using recombinant Escherichia coli coexpressing a esterase and transaminase were developed, wherein the desired expression level of each enzyme was achieved by promotor engineering. The small‐scale reactions (30 ml) performed under optimized conditions at varying amounts of substrate (100–300 mM) resulted in excellent conversions of 82%–95% for the desired product. Finally, a kilogram‐scale enzymatic reaction (250 mM substrate, 220 L) was carried out to produce β‐amino acid (229 mM). Sitagliptin phosphate was chemically synthesized from β‐amino acids with 82% yield and > 99% purity. [ABSTRACT FROM AUTHOR]

Path planning research plays a vital role in terms of safety and comfort in autonomous driving systems. This paper focuses on safe driving and comfort riding through path planning in autonomous driving applications and proposes autonomous driving path planning through an optimal controller integrating obstacle-dependent Gaussian (ODG) and model prediction control (MPC). The ODG algorithm integrates the information from the sensors and calculates the risk factors in the driving environment. The MPC function finds vehicle control signals close to the objective function under limited conditions, such as the structural shape of the vehicle and road driving conditions. The proposed method provides safe control and minimizes vehicle shaking due to the tendency to respond to avoid obstacles quickly. We conducted an experiment using mobile robots, similar to an actual vehicle, to verify the proposed algorithm performance. The experimental results show that the average safety metric is 72.34%, a higher ISO-2631 comport score than others, while the average processing time is approximately 14.2 ms/frame. [ABSTRACT FROM AUTHOR]

A novel hybrid polishing process, called laser-assisted polishing (LAP), was proposed in this study for improving the material removal rate (MRR) of polishing silicon carbide (SiC) by combining a CO2 laser source and a conventional polishing machine. The results showed that the MRR increased by 79.0% using the LAP process on the cracked and oxidized SiC sample surface as compared to that using the mechanical polishing of a normal sample. It was also found that the laser-induced crack was the main mechanism underlying the growth of MRR in the LAP process. It was expected that the proposed LAP process and the material removal mechanism might shed light on the expansion of the hybrid machining field and better industrial application of SiC. [ABSTRACT FROM AUTHOR]

We developed a 193-nm deep ultraviolet (DUV) microscope system based on the reflection mode for a precise inspection of various types of defects/cracks on large optical surfaces of the order of one meter in size. Without preprocessing the sample at room temperature and atmospheric pressure, which is commonly necessary for electron microscopy, the reflective 193-nm DUV microscope was used to directly observe optical surface defects in a manner similar to conventional optical microscopes. In addition, the limitations on the selection of materials and thickness of optical samples of transmittive DUV microscopes were overcome. DUV microscope imaging and the analysis on the spatial resolution were verified using a 1D grating structure with a 225-nm line width. This system could be widely applied as an inspection tool because it provides high resolution at the 200-nm scale that is close to the diffraction limit of a 193-nm DUV beam. In the near future, it is expected that our system would be extended to nano/bio imaging as well as the inspection of large optical surfaces. [ABSTRACT FROM AUTHOR]

A one‐pot deracemization strategy for α‐chiral amines is reported involving an enantioselective deamination to the corresponding ketone followed by a stereoselective amination by enantiocomplementary biocatalysts. Notably, this cascade employing a ω‐transaminase and amine dehydrogenase enabled the access to both (R)‐and (S)‐amine products, just by controlling the directions of the reactions catalyzed by them. A wide range of (R)‐and (S)‐amines was obtained with excellent conversions (>80 %) and enantiomeric excess (>99 % ee). Finally, preparative scale syntheses led to obtain enantiopure (R)‐ and (S)‐13 with the isolated yields of 53 and 75 %, respectively. Make a choice, make it right: Novel one‐pot deracemization cascade, employing amine dehydrogenase and ω‐transaminase, is reported for the synthesis of enantiopure amines with excellent conversions [ABSTRACT FROM AUTHOR]

A recyclable glutamate amine donor system employing transaminase (TA), glutamate dehydrogenase (GluDH) and mutant formate dehydrogenase (FDHm) was developed, wherein amine donor Glu was regenerated using GluDH and thereby circumvented the inhibition of TA by α‐ketoglutarate. Various enantiopure β‐, γ‐amino acids, and amines were successfully synthesized with high conversions and excellent enantiomeric excess using this system. Donate amines: A recyclable glutamate amine donor system employing transaminase (TA), glutamate dehydrogenase (GluDH) and mutant formate dehydrogenase (FDHm) was developed for the synthesis of enantiopure β‐, and γ‐amino acids [ABSTRACT FROM AUTHOR]

Abstract: Emulsification‐induced assembly is employed to allow structural diversity in nanoaggregates of a biocompatible amphiphilic polymer, poly(ethylene oxide)‐block‐poly(ε‐caprolactone). Onion‐like vesicles are efficiently produced by tuning the interfacial instability of the oil‐in‐water emulsion. The increase in the polymer concentration and use of the organic solvents with a low interfacial tension between water and the oil phase lead to a strong tendency of emulsion droplets to generate the onion‐like vesicles. The vesicular networks and fibers are also obtained by controlling the concentration and type of the surfactant, respectively. Interestingly, the onion‐like vesicles composed of alternating walls and water channels and the vesicular networks originated from a string of vesicles show dual‐loading ability for hydrophobic and hydrophilic dyes but slightly different loading capacities. This result indicates that the development of a methodology to fabricate well‐defined, unique nanostructures, such as multivesicular and multilamellar nanostructures, and subsequent elucidation of their structure–property relationships can provide useful guidance in the design of novel biomedical materials. [ABSTRACT FROM AUTHOR]

We report parallel spectral-domain optical coherence tomography (OCT) at 500 000 A-scan/s. This is the highest-speed spectral-domain (SD) OCT system using a single line camera. Spectrally encoded line-field scanning is proposed to increase the imaging speed in SD-OCT effectively, and the tradeoff between speed, depth range, and sensitivity is demonstrated. We show that three imaging modes of 125k, 250k, and 500k A-scan/s can be simply switched according to the sample to be imaged considering the depth range and sensitivity. To demonstrate the biological imaging performance of the high-speed imaging modes of the spectrally encoded line-field OCT system, human skin and a whole leaf were imaged at the speed of 250k and 500k A-scan/s, respectively. In addition, there is no sensitivity dependence in the B-scan direction, which is implicit in line-field parallel OCT using line focusing of a Gaussian beam with a cylindrical lens. [ABSTRACT FROM AUTHOR]

Cell-penetrating peptides ( CPPs), originated from membrane translocating sequences of viruses, can deliver biomolecules effectively into cells. Research on natural and synthetic CPPs, for delivering drugs and genes reveals that this process requires cellular uptake independent of receptors and endosomes to minimize damage to the cell membrane. To this end, we conjugated CPP-derived oligopeptides to the surface of polyamidoamine ( PAMAM) dendrimers to develop novel nanocarriers that improve cellular uptake transfection efficiency. PAMAM generation 4 ( G4) was conjugated with oligopeptides composed of lysine and phenylalanine ( KFF, FFK). The DNA condensation efficiency of PAMAM G4-KFF and PAMAM G4-FFK was determined using an agarose gel retardation assay. The sizes of the polyplexes were determined using dynamic light scattering as well as scanning and transmission electron microscopy. Cytotoxicity and transfection efficiency were evaluated using the HeLa and HepG2 cells. The transfection efficiencies of PAMAM G4-KFF and PAMAM G4-FFK were comparable with that of the gold-standard transfection reagent polyethylenimine ( PEI25 kDa). These results suggest that these nanocarriers will serve as efficient non-viral vehicles for gene therapy. [ABSTRACT FROM AUTHOR]

A real-time compensation method for TFT variation is proposed for AMOLED displays. This method enables a column driver to sense TFT current of each pixel using a power line as a current sensing line while driving a pixel without increasing a scan time. A fast OLED degradation sensing is also possible to compensate the image sticking problem. A target application of the proposed driver is a simultaneous emission full-HD AMOLED TV, whose scan time is 7.5μs at a scan frequency of 120Hz. [ABSTRACT FROM AUTHOR]

We report a compact all-optical side-firing probe directly ablated on a mode-expanded hybrid fiber end using a high-precision femtosecond laser processing technique. A segment of coreless silica fiber was adopted to achieve a large beam size and manipulation of the far field divergence angle. The radiating beam properties of the side-firing tip have been experimentally investigated and compared with numerical simulations. [ABSTRACT FROM PUBLISHER]

Simple Summary: Despite the therapeutic advances, lung cancer is the most dangerous cancer with poor 5-year survival rate due to metastasis and recurrence. Accumulated evidence indicates that the epithelial–mesenchymal transition (EMT) is considered to be responsible for the lung cancer metastasis; however, the transcriptional frameworks that regulate EMT-related gene expression are still poorly understood. Here, we suggest that cooperation of TCF4-TWIST1 controlled by the PGC1α-ID1 transcriptional axis mediates EMT and lung cancer metastasis, and that this molecular framework is an attractive target for lung cancer diagnosis and treatment. PGC1α oppositely regulates cancer metastasis in melanoma, breast, and pancreatic cancer; however, little is known about its impact on lung cancer metastasis. Transcriptome and in vivo xenograft analysis show that a decreased PGC1α correlates with the epithelial–mesenchymal transition (EMT) and lung cancer metastasis. The deletion of a single Pgc1α allele in mice promotes bone metastasis of KrasG12D-driven lung cancer. Mechanistically, PGC1α predominantly activates ID1 expression, which interferes with TCF4-TWIST1 cooperation during EMT. Bioinformatic and clinical studies have shown that PGC1α and ID1 are downregulated in lung cancer, and correlate with a poor survival rate. Our study indicates that TCF4-TWIST1-mediated EMT, which is regulated by the PGC1α-ID1 transcriptional axis, is a potential diagnostic and therapeutic target for metastatic lung cancer. [ABSTRACT FROM AUTHOR]

A simple and compact lensed dual-fiber probe having high collection efficiency for fluorescence signal is demonstrated. A lensed dual-fiber probe, composed of two parallel fibers and a common focusing lens, was simply implemented by the electric arc discharge method. The performance of the proposed probe was evaluated experimentally by measuring the reflection powers and fluorescence spectra of well-known targets and a fresh ginkgo leaf. The experimental result shows that the proposed probe provides a six-fold increase in the collection efficiency compared to measurements without the lens. In addition, the signal collection occurs very close to the probe surface with a suitably localized depth. [ABSTRACT FROM PUBLISHER]

In this study, a portable and large-area blackbody system was developed following a series of processes including design, computational analysis, fabrication, and experimental analysis and evaluation. The blackbody system was designed to be lightweight (5 kg), and its temperature could exceed the ambient temperature by up to 15 °C under operation. A carbon-fiber-based heat source was used to achieve a uniform temperature distribution. A heat shield fabricated from an insulation material was embedded at the opposite side of the heating element to minimize heat loss. A prototype of the blackbody system was fabricated based on the design and transient coupled electro-thermal simulation results. The operation performance of this system, such as the thermal response, signal transfer function, and noise equivalent temperature difference, was evaluated by employing an infrared imaging system. In addition, emissivity was measured during operation. The results of this study show that the developed portable and large-area blackbody system can be expected to serve as a reliable reference source for the calibration of aerial infrared images for the application of aerial infrared techniques to remote sensing. [ABSTRACT FROM AUTHOR]