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41.
Abstract Error-diffused quantization has been applied to the generation of cell-oriented computer-generated Fourier transform holograms, resulting in reduced reconstruction errors. Improvements are demonstrated when applied to the algorithms of Lohmann, Lee and Burckhardt after invoking realistic constraints on the minimum size of the printable spot for an electrophotographic laser printer. 相似文献
42.
Noori M. Cata Saady Subba Rao Chaganti Jerald A. Lalman Sathyanarayanan S. Veeravalli Saravanan R. Shanmugam Daniel D. Heath 《International Journal of Hydrogen Energy》2012
The effects of lauric (LUA), myristic (MA), palmitic (PA), and a mixture of myristic:palmitic (MA:PA) acids on hydrogen (H2) production from glucose degradation using anaerobic mixed cultures were assessed at 37 °C with an initial pH set at 5.0 and 7.131 mM of each acid. The maximum H2 yield (2.53 ± 0.18 mol mol−1 glucose) was observed in cultures treated with PA. A principal component analysis (PCA) of the by-products and the microbial population data sets detected similarities between the controls and PA treated cultures; however, differences were observed between the controls and PA treated cultures in comparison to the MA and LUA treated cultures. The flux balance analysis (FBA) showed that PA decreased the quantity of H2 consumed via homoacetogenesis compared to the other LCFAs. The control culture was dominated by Thermoanaerovibrio acidaminovorans (60%), Geobacillus sp. and Eubacterium sp. (28%), while Clostridium sp. was less than 1%. Treatment with PA, MA, MA:PA, or LUA increased the H2 producers (Clostridium sp. and Bacillus sp.) population by approximately 48, 67, 86, and 86%, respectively. 相似文献
43.
Microsystem Technologies - The recent availability of inexpensive digital recording and storage devices have created an environment to obtain, replicate and distribute digital content without any... 相似文献
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Akila Swaminathan Sree Rama Chaitanya Sridhara Swaraj Sinha Shunmugam Nagarajan Uma Maheswari Balaguru Jamila H Siamwala Saranya Rajendran Uttara Saran Suvro Chatterjee 《Journal of food science》2012,77(12):H273-H279
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health. 相似文献
46.
Balasubramanian Nagarajan Sylvie Castagne Zhongke Wang H.Y. Zheng Kartikeyan Nadarajan 《International Journal of Material Forming》2017,10(1):109-123
Flexible Pad Laser Shock Forming (FPLSF) is a new microforming process using laser-induced shock pressure and a hyperelastic flexible pad to induce high strain-rate (~105 s?1) plastic deformation on metallic foils to produce 3D microcraters. This paper studies the effect of two significant process parameters of FPLSF, flexible pad material and its thickness, on the deformation characteristics of the metal foils using experiments and finite element analysis. A finite element model is developed to simulate the FPLSF process. The stress-strain distribution across the foil and the flexible pad at different process stages of FPLSF are studied using FE analysis. Flexible pad materials including silicone rubber, polyurethane rubber, and natural rubber with thicknesses ranging between 300 μm and 3000 μm have been investigated in detail. Experimental results highlight that both the hardness and thickness of the flexible pad significantly influence the deformed crater geometry, thickness distribution across the formed crater and surface hardness at the crater surfaces. The experimental results are correlated with the stress-strain distributions from finite element analysis to study the underlying behaviors. 相似文献
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Seongmi Ji Eun Sun Moon Han Byul Noh Hyun Jung Park Seongdae Kim Sung Oh Nagarajan Vinod Chang Won Choi Kilhan Kwak 《International journal of molecular sciences》2022,23(4)
Listeria monocytogenes (Lm) bacterial ghosts (LMGs) were produced by the minimum inhibitory concentration (MIC) of HCl, H2SO4, and NaOH. Acid and alkali effects on the LMGs were compared by in vitro and in vivo analyses. Scanning electron microscope showed that all chemicals form lysis pores on the Lm cell envelopes. Real-time qPCR revealed a complete absence of genomic DNA in HCl- and H2SO4-induced LMGs but not in NaOH-induced LMGs. HCl-, H2SO4- and NaOH-induced LMGs showed weaker or missing protein bands on SDS-PAGE gel when compared to wild-type Lm. Murine macrophages exposed to the HCl-induced LMGs showed higher cell viability than those exposed to NaOH-induced LMGs or wild-type Lm. The maximum level of cytokine expression (TNF-α, iNOS, IFN-γ, and IL-10 mRNA) was observed in the macrophages exposed to NaOH-induced LMGs, while that of IL-1β mRNA was observed in the macrophages exposed to HCl-induced LMGs. To investigate LMGs as a vaccine candidate, mice were divided into PBS buffer-injected, HCl- and NaOH-induced LMGs immunized groups. Mice vaccinated with HCl- and NOH-induced LMGs, respectively, significantly increased in specific IgG antibodies, bactericidal activities of serum, and CD4+ and CD8+ T-cell population. Antigenic Lm proteins reacted with antisera against HCl- and NOH-induced LMGs, respectively. Bacterial loads in HCl- and NaOH-induced LMGs immunized mice were significantly lower than PBS-injected mice after virulent Lm challenges. It suggested that vaccination with LMGs induces both humoral and cell-mediated immune responses and protects against virulent challenges. 相似文献
49.
S. Nagarajan 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(10):1800-1806
Results on photoluminescence and photostimulated luminescence studies of KBr1−xIx:TlI (0.01 and 0.05 mol%) mixed crystals grown in vacuum and air are presented. Photoluminescence spectra of the mixed crystals excited in the A-absorption band of KBr:Tl+ exhibited the characteristic emission bands of Tl+ ions in KBr:Tl+. When excited in the low energy tail of A-band absorption, additional emission bands were observed. Compared with earlier reports, excitation bands observed around 4.8, 4.6 and 4.4 eV are attributed to complex thallium centres of the form TlBr6−nIn (n = 0, 1, 2, 3). Photostimulated luminescence of γ-irradiated KBr1−xIx:TlI mixed crystals showed the presence of emission bands similar to the characteristic photoluminescence of Tl+ ions. The photostimulated luminescence slightly shifted towards the low energy side with increasing iodide composition x. The mechanism of emission in these mixed crystals is discussed. Dose response and storage stability (fading characteristics) in these mixed crystals are reported. 相似文献
50.
We demonstrate an easily-implemented, edge-plate geometry for electrospinning and produce high quality nanofibers from unconfined polymer fluids. We show that for electrospinning in general, the electric field gradient, not just the electric field amplitude, is a critical parameter for successful self-initiated jetting. Considering a single spinning site, the edge-plate configuration resulted in the same or a higher fabrication rate as traditional needle electrospinning, while producing nanofibers similar in quality (diameter, diameter distribution, and collected mat porosity); moreover, this novel configuration operates without the possibility of clogging and has high potential for scale-up. We analyze the fundamental physical processes which underlie edge-plate electrospinning, including electric field, working distance, and feed rate dependence and the resultant changes to the linear and whipping regions, and thus to the fiber diameter. We conclude that the edge-plate configuration functions in a remarkably similar manner to traditional needle electrospinning. 相似文献