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21.
Lactosylceramide (LacCer), also known as CD17/CDw17, is a member of a large family of small molecular weight compounds known as glycosphingolipids. It plays a pivotal role in the biosynthesis of glycosphingolipids, primarily by way of serving as a precursor to the majority of its higher homolog sub-families such as gangliosides, sulfatides, fucosylated-glycosphingolipids and complex neutral glycosphingolipids—some of which confer “second-messenger” and receptor functions. LacCer is an integral component of the “lipid rafts,” serving as a conduit to transduce external stimuli into multiple phenotypes, which may contribute to mortality and morbidity in man and in mouse models of human disease. LacCer is synthesized by the action of LacCer synthase (β-1,4 galactosyltransferase), which transfers galactose from uridine diphosphate galactose (UDP-galactose) to glucosylceramide (GlcCer). The convergence of multiple physiologically relevant external stimuli/agonists—platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), stress, cigarette smoke/nicotine, tumor necrosis factor-α (TNF-α), and in particular, oxidized low-density lipoprotein (ox-LDL)—on β-1,4 galactosyltransferase results in its phosphorylation or activation, via a “turn-key” reaction, generating LacCer. This newly synthesized LacCer activates NADPH (nicotinamide adenine dihydrogen phosphate) oxidase to generate reactive oxygen species (ROS) and a highly “oxidative stress” environment, which trigger a cascade of signaling molecules and pathways and initiate diverse phenotypes like inflammation and atherosclerosis. For instance, LacCer activates an enzyme, cytosolic phospholipase A2 (cPLA2), which cleaves arachidonic acid from phosphatidylcholine. In turn, arachidonic acid serves as a precursor to eicosanoids and prostaglandin, which transduce a cascade of reactions leading to inflammation—a major phenotype underscoring the initiation and progression of several debilitating diseases such as atherosclerosis and cancer. Our aim here is to present an updated account of studies made in the field of LacCer metabolism and signaling using multiple animal models of human disease, human tissue, and cell-based studies. These advancements have led us to propose that previously unrelated phenotypes converge in a LacCer-centric manner. This LacCer synthase/LacCer-induced “oxidative stress” environment contributes to inflammation, atherosclerosis, skin conditions, hair greying, cardiovascular disease, and diabetes due to mitochondrial dysfunction. Thus, targeting LacCer synthase may well be the answer to remedy these pathologies. 相似文献
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Carlin Vieri Grace Lee Nikhil Balram Sang Hoon Jung Joon Young Yang Soo Young Yoon In Byeong Kang 《Journal of the Society for Information Display》2018,26(5):314-324
We developed and fabricated the world's highest resolution (18 megapixel, 1443 ppi) OLED on glass display panel. The design uses a white OLED with color filter structure for high density pixelization and an n‐type LTPS backplane for faster response time than mobile phone displays. A custom high bandwidth driver IC was fabricated. We developed a foveated pixel pipeline appropriate for virtual reality and augmented reality applications, especially mobile systems. 相似文献
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David M. Hoffman Chris McKenzie Brion Koprowski Asif Iqbal Nikhil Balram 《Journal of the Society for Information Display》2019,27(4):207-222
In order to create a satisfying experience with near‐eye displays, the content must be adapted to be legible on the display used. New displays are using subpixel arrangements that can limit the minimum resolvable feature size to something greater than with the conventional RGB stripe arrangement. We conducted an experiment to measure the minimum and preferred size of text in two virtual reality (VR) displays systems and find that the text size is display limited. We then measure several displays with different pixel arrangements to determine whether the subpixel arrangement could impact legibility. We propose several Fourier metrics that can be computed from the measured data to categorize the capability of the display and describe a framework for selecting the appropriate content from a set of discrete tiers. 相似文献
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Ajaz S. Hussain Robert D. Johnson Padmaja Shivanand Michael A. Zoglio 《Drug development and industrial pharmacy》1994,20(17):2645-2657
Blends of hydroxyethylcellulose (HEC) and sodium carboxymethylcellulose (NaCMC) were used to achieve zero order release of chlorpheniramine maleate (CM) from hydrophilic matrix capsules. Dynamic swelling/erosion and response surface measurements were made to provide an insight into the drug release behavior. The drug to total polymer and the HEC to NaCMC ratio influences the rate of drug release. NaCMC appears to influence water uptake and erosion of the matrix mixture. The factors by which zero-order drug release is achieved may include synchronization of the rates of water uptake and polymer erosion even though a constant diffusional pathlength may not be maintained. The combined mixture factorial design presented in this study allows for the characterization and optimization of the drug release profiles. 相似文献
25.
The paper describes a lossy image codec that uses a noncausal (or bilateral) prediction model coupled with vector quantization. The noncausal prediction model is an alternative to the causal (or unilateral) model that is commonly used in differential pulse code modulation (DPCM) and other codecs with a predictive component. We show how to obtain a recursive implementation of the noncausal image model without compromising its optimality and how to apply this in coding in much the same way as a causal predictor. We report experimental compression results that demonstrate the superiority of using a noncausal model based predictor over using traditional causal predictors. The codec is shown to produce high-quality compressed images at low bit rates such as 0.375 b/pixel. This quality is contrasted with the degraded images that are produced at the same bit rates by codecs using causal predictors or standard discrete cosine transform/Joint Photographic Experts Group-based (DCT/JPEG-based) algorithms. 相似文献
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Taesung Kim Bo Ye Chung Phan Vu Nikhil Balram Hugo Steemers 《Journal of the Society for Information Display》2009,17(3):203-212
Abstract— LCD motion blur is a well‐known phenomenon, and several approaches have been developed to address it. This includes very‐high‐performance approaches based on motion‐compensated frame rate conversion (MC‐FRC) and very‐low‐cost approaches based on impulsive driving. Impulsive‐driving schemes are attractive because of their low cost, but suffer from two significant issues — loss of luminance and large‐area flicker. A new impulsive‐driving approach using motion‐adaptive alternate gamma driving (MA‐AGD), which removes motion blur and preserves the original luminance level without causing large‐area flicker, is proposed. 相似文献
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The external loop airlift reactor(EL-ALR) is widely used for gas-liquid reactions. It's advantage of good heat and mass transfer rates compared to conventional bubble column reactors. In the case of fermentation application where a medium is highly viscous and coalescing in nature, internal in riser helps in the improvement of the interfacial area as well as in the reduction of liquid-phase back mixing. The computational fluid dynamic(CFD) as a tool is used to design and scale-up of sectionalized external loop airlift reactor. The present work deals with computational fluid dynamics(CFD) techniques and experimental measurement of a gas hold-up, liquid circulation velocity, liquid axial velocity, Sauter mean bubble diameter over a broad range of superficial gas velocity 0.0024≤U_G≤0.0168 m·s~(-1). The correlation has been made for bubble size distribution with specific power consumption for different plate configurations. The effects of an internal on different mass transfer models have been completed to assess their suitability.The predicted local mass transfer coefficient has been found higher in the sectionalized external loop airlift reactor than the conventional EL-ALR. 相似文献
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A nonlinear mirror composed of a lithium triborate crystal and a dichroic output coupler is used to passively mode lock an Nd:YVO4 laser that is pumped by a diode laser array. A mode-locked output power of 3.2 W, a repetition rate of 178 MHz, a pulse width of 8.4 ps, and a beam quality parameter (M2) of 1.27 are obtained at 1064 nm for a pump power of 10.0 W. The numerical simulation for the steady-state pulse width agrees well with the bandwidth-limited value. A double-pass average gain g(ave) is defined by considering the constancy of the output energy. In the simulation g(ave) is kept as a free parameter, and its value required for the bandwidth-limited pulse is found to be 0.047, whereas its calculated value, based on our definition, is 0.057. 相似文献
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Shivanand Payamalle Smita Shinde Kadanthottu Sebastian Joseph Sonal Mutakekar Manisha Murgude Rakesh Tawadare Hosakatte Niranjana Murthy 《Journal of the American Oil Chemists' Society》2016,93(2):295-297
The physicochemical and fatty acid compositions of seed oil extracted from Thunbergia fragrans were determined. The oil content, free fatty acids, peroxide value, saponification value and iodine value were 21.70 %, 2.25 % (as oleic acid), 9.6 (mequiv. O2/kg), 191.71 (mg KOH/g) and 127.84 (g/100 g oil) respectively. The fatty acid profiles of the methyl esters showed the presence of 90.16 % unsaturated fatty acids and 9.84 % saturated fatty acids. Palmitoleic acid, which is usually found in marine foods and is unique in seed oils of botanical origin, was the major component (79.24 %). The oil can also be used in industries for the preparation of liquid soaps, shampoos and alkyd resin. 相似文献