Vitamin D Is Required for IFN- -Mediated Antimicrobial Activity of Human Macrophages

Fabri, M.,Stenger, S.,Shin, D.-M.,Yuk, J.-M.,Liu, P. T.,Realegeno, S.,Lee, H.-M.,Krutzik, S. R.,Schenk, M.,Sieling, P. A.,Teles, R.,Montoya, D.,Iyer, S. S.,Bruns, H.,Lewinsohn, D. M.,Hollis, B. W.,Hew American Association for the Advancement of Scienc 2011 Science translational medicine Vol.3 No.104

<P>Control of tuberculosis worldwide depends on our understanding of human immune mechanisms, which combat the infection. Acquired T cell responses are critical for host defense against microbial pathogens, yet the mechanisms by which they act in humans remain unclear. We report that T cells, by the release of interferon-γ (IFN-γ), induce autophagy, phagosomal maturation, the production of antimicrobial peptides such as cathelicidin, and antimicrobial activity against Mycobacterium tuberculosis in human macrophages via a vitamin D-dependent pathway. IFN-γ induced the antimicrobial pathway in human macrophages cultured in vitamin D-sufficient sera, but not in sera from African-Americans that have lower amounts of vitamin D and who are more susceptible to tuberculosis. In vitro supplementation of vitamin D-deficient serum with 25-hydroxyvitamin D3 restored IFN-γ-induced antimicrobial peptide expression, autophagy, phagosome-lysosome fusion, and antimicrobial activity. These results suggest a mechanism in which vitamin D is required for acquired immunity to overcome the ability of intracellular pathogens to evade macrophage-mediated antimicrobial responses. The present findings underscore the importance of adequate amounts of vitamin D in all human populations for sustaining both innate and acquired immunity against infection.</P>

Tailoring the defects and carrier density for beyond 10% efficient CZTSe thin film solar cells

Li, J.,Kim, S.,Nam, D.,Liu, X.,Kim, J.,Cheong, H.,Liu, W.,Li, H.,Sun, Y.,Zhang, Y. North-Holland ; Elsevier Science Ltd 2017 Solar energy materials and solar cells Vol.159 No.-

The defects states and carrier density of CZTSe absorber layers are two of the crucial factors that decide the photovoltaic performance of CZTSe thin film solar cells. Fine tailoring the defects and carrier density is a key to push the power conversion efficiency of CZTSe solar cells to a more competitive level. In this work, the phase properties, defect states, and carrier density of CZTSe thin film are well controlled by fine tuning the ratio of Zn/Sn in the range from 0.75 to 1.27. Capacity-Voltage measurements and Admittance Spectroscopy are used to characterize the carrier density, depletion region width, and defect states of the CZTSe solar cells. The results indicate that the defects states and carrier density of CZTSe layer are very sensitive to the ratio of Zn/Sn. Combining experimental results and numerical simulation, the statistic regularities of the photovoltaic parameters of the CZTSe solar cells with different ratios of Zn/Sn is well explained. The increase of V<SUB>OC</SUB> of CZTSe solar cells with the ratio of Zn/Sn is related to both the increased carrier density and the decreased deep level defects states. The decline of J<SUB>SC</SUB> of the Zn-rich solar cells is caused by both the shrunken depletion region width and a large barrier caused by ZnSe phase. This barrier is the cause for a low fill factor in the Zn-rich solar cells. Overall, the CZTSe solar cells with a stoichiometric ratio of Zn/Sn=1.02 have favorable defects property and carrier density, thus resulting in the highest photovoltaic efficiency of 10.21%.

Enhanced energy storage properties in PbZrO3 thin films via the incorporation of NiO

Wang X.W.,Chen J.Y.,Hu S.Y.,Yu K.X.,Yang F.,Shi Y.J.,Li J.H.,Hou M.Z.,Liu A.D.,Zheng M.M.,Yin S.Q.,Hu Y.C.,Shang J. 한국물리학회 2023 Current Applied Physics Vol.52 No.-

In this study, NiO–PbZrO3 composite films were deposited on SiO2/Si substrates buffered with LaNiO3 films via the sol-gel coating technique. The effects of NiO addition in PZO thin films on the microstructure, dielectric properties, leakage mechanism, ferroelectric properties and energy storage properties have been discussed. The dielectric constant increased with the addition of NiO, while the leakage current density decreased. Compared with pure PZO films, the maximum polarization of the composite films was improved. For the composite films prepared using the NiO precursor solution with 0.05 mol/L, the recoverable energy storage density of the NiO-PZO composite film is up to 19.6 J/cm3 under the electric field of 1038 kV/cm, which is 30% higher than that of the pure PZO film under the same conditions. Also, the energy storage efficiency of the composite film reaches 48%. Accordingly, we demonstrate a simple and convenient method by adding NiO to fabricate thin films with high energy storage performance.

Dietary plant extracts modulate gene expression profiles in ileal mucosa of weaned pigs after an <i>Escherichia coli</i> infection

Liu, Y.,Song, M.,Che, T. M.,Lee, J. J.,Bravo, D.,Maddox, C. W.,Pettigrew, J. E. American Society of Animal Science 2014 Journal of Animal Science Vol.92 No.5

<P>This study was conducted to characterize the effects of infection with a pathogenic F-18 <I>Escherichia coli</I> and 3 different plant extracts on gene expression of ileal mucosa in weaned pigs. Weaned pigs (total = 64, 6.3 ± 0.2 kg BW, and 21-d old) were housed in individual pens for 15 d, 4 d before and 11 d after the first inoculation (d 0). Treatments were in a 2 × 4 factorial arrangement: with or without an F-18 <I>E. coli</I> challenge and 4 diets (a nursery basal, control diet [CON], 10 ppm of capsicum oleoresin [CAP], garlic botanical [GAR], or turmeric oleoresin [TUR]). Results reported elsewhere showed that the plant extracts reduced diarrhea in challenged pigs. Total RNA (4 pigs/treatment) was extracted from ileal mucosa of pigs at d 5 post inoculation. Double-stranded cDNA was amplified, labeled, and further hybridized to the microarray, and data were analyzed in R. Differential gene expression was tested by fitting a mixed linear model in a 2 × 4 factorial ANOVA. Bioinformatics analysis was conducted by DAVID Bioinformatics Resources 6.7 (<B>DAVID;</B> National Institute of Allergy and Infectious Diseases <B>[</B>NIAID, NIH<B>],</B> http://david.abcc.ncifcrf.gov). The <I>E. coli</I> infection altered (<I>P</I> < 0.05) the expression of 240 genes in pigs fed the CON (148 up- and 92 down-regulated). Compared with the infected CON, feeding CAP, GAR, or TUR altered (<I>P</I> < 0.05) the expression of 52 genes (18 up, 34 down), 117 genes (34 up- and 83 down-regulated), or 84 genes (16 up- and 68 down-regulated), respectively, often counteracting the effects of <I>E. coli</I>. The <I>E. coli</I> infection up-regulated (<I>P</I> < 0.05) the expression of genes related to the activation of immune response and complement and coagulation cascades, but down-regulated (<I>P</I> < 0.05) the expression of genes involved in protein synthesis and accumulation. Compared with the CON, feeding CAP and GAR increased (<I>P</I> < 0.05) the expression of genes related to integrity of membranes in infected pigs, indicating enhanced gut mucosa health. Moreover, feeding all 3 plant extracts reduced (<I>P</I> < 0.05) the expression of genes associated with antigen presentation or other biological processes of immune responses, indicating they attenuated overstimulation of immune responses caused by <I>E. coli</I>. These findings may explain why diarrhea was reduced and clinical immune responses were ameliorated in infected pigs fed plant extracts. In conclusion, plant extracts altered the expression of genes in ileal mucosa of <I>E. coli</I>-infected pigs, perhaps leading to the reduction in diarrhea reported previously.</P>

Effects of stale maize on growth performance, immunity, intestinal morphology and antioxidant capacity in broilers

Liu, J.B.,Yan, H.L.,Zhang, Y.,Hu, Y.D.,Zhang, H.F. Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.4

Objective: This study was conducted to determine the effects of stale maize on growth performance, immunity, intestinal morphology, and antioxidant capacity in broilers. Methods: A total of 800 one-day-old male Arbor Acres broilers (45.4±0.5 g) were blocked based on body weight, and then allocated randomly to 2 treatments with 20 cages per treatment and 20 broilers per cage in this 6-week experiment. Dietary treatments included a basal diet and diets with 100% of control maize replaced by stale maize. Results: The content of fat acidity value was higher (p<0.05) while the starch, activities of catalase and peroxidase were lower (p<0.05) than the control maize. Feeding stale maize diets reduced (p<0.05) average daily feed intake (ADFI) throughout the experiment, feed conversion ratio (FCR) during d 0 to 21 and the whole experiment as well as relative weight of liver, spleen, bursa of Fabricius and thymus (p<0.05) on d 21. Feeding stale maize diets decreased jejunum villus height (VH) and VH/crypt depth (CD) (p<0.05) on d 21 and 42 as well as ileum VH/CD on d 42. The levels of immunoglobulin G, acid α-naphthylacetate esterase positive ratios and lymphocyte proliferation on d 21 and 42 as well as lysozyme activity and avian influenza antibody H₅N₁ titer on d 21 decreased (p<0.05) by the stale maize. Feeding stale maize diets reduced (p<0.05) serum interferon-γ, tumor necrosis factor-α, interleukin-2 on d 21 and interleukin-6 on d 21 and 42. Broilers fed stale maize diets had lower levels of (p<0.05) total antioxidative capacity on d 42, superoxide dismutase and glutathione peroxidase on d 21 and 42, but higher (p<0.05) levels of malondialdehyde on d 21 and 42. Conclusion: Feeding 100% stale maize decreased ADFI and FCR, caused adverse effects on immunity and antioxidant function and altered intestinal morphology in broilers.

High-Efficient Conversion of CO2 in AC-Pulsed Tornado Gliding Arc Plasma

Liu, J. L.,Park, H. W.,Chung, W. J.,Park, D. W. Springer Science + Business Media 2016 Plasma chemistry and plasma processing Vol.36 No.2

<P>An AC-pulsed tornado gliding arc plasma was employed for CO2 conversion via CO2 decomposition and dry reforming reactions. A stable and high-efficient constant arc length discharge mode was obtained in this plasma reactor. And then, CO2 conversion was studied under this discharge mode. In the case of CH4/CO2 = 0, CO2 was converted to CO and O-2 via the CO2 decomposition reaction. Energy efficiency of 29 % was attained at CO2 conversion of 6 %. With strong reducing agent CH4 added into CO2, the main contributor of CO2 conversion changed from CO2 decomposition to dry reforming of CH4. Conversions of CH4 and CO2, energy efficiency and energy cost changed sharply at CO2/CH4 ratios lower than 1/4, while they changed slowly at CH4/CO2 ratios above 1/4. In the case of CH4/CO2 = 2/3, energy efficiency of 68 % and syngas energy cost of 1.6 eV/mole were achieved at CH4 conversion of 29 % and CO2 conversion of 22 %.</P>

INVESTIGATION OF PARTICLE EMISSION CHARACTERISTICS FROM A DIESEL ENGINE WITH A DIESEL PARTICULATE FILTER FOR ALTERNATIVE FUELS

D. WANG,Z. C. LIU,J. TIAN,J. W. LIU,J. R. ZHANG 한국자동차공학회 2012 International journal of automotive technology Vol.13 No.7

Particle number measurement is a new approach to determine emission, which may be more accurate at very low emission levels than when using gravimetric measurements. An experimental study was performed to investigate the effect of fuel properties on the performance, combustion process, regulated gaseous emissions and particle number emissions of a diesel engine with an uncatalyzed diesel particulate filter (DPF). The effect of the filter on the particle size distribution was reported. The DPF number-based filtration efficiency in terms of number efficiency and fractional efficiency for petroleum diesel fuel and two alternative fuels, BTL and GTL, were analyzed. For nearly all test modes, the filter had a higher number efficiency for diesel than for BTL and GTL. The DPF fractional efficiency showed it was highly dependent on fuel type and varied widely at each size range. For diesel, the filter fractional efficiency was sufficiently high and behaved as predicted by filtration theory. For BTL and GTL, the fractional performance of the filter decreased when unexpectedly low efficiencies within the nuclei mode were exhibited. This research will be helpful in understanding DPF number-based filtration performance for alternative fuels and will provide information for the development of particulate emission control technology.

Simulated biogas oxidative reforming in AC-pulsed gliding arc discharge

Liu, J.L.,Park, H.W.,Chung, W.J.,Ahn, W.S.,Park, D.W. Elsevier 2016 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.285 No.-

High-efficient oxidative reforming of simulated biogas in a novel AC-pulsed tornado gliding arc discharge was performed. The effects of two important factors, O<SUB>2</SUB>/CH<SUB>4</SUB> ratio and specific energy input (SEI), were studied. Increasing the O<SUB>2</SUB>/CH<SUB>4</SUB> ratio positively affected the reactant conversion, dry-basis concentration, and energy cost of syngas over the tested range of O<SUB>2</SUB>/CH<SUB>4</SUB> ratios. Increasing the SEI increased the reactant conversion and dry-basis concentration of syngas but significantly increased the energy cost as well. Remarkable CO<SUB>2</SUB> conversion 25% (27%) and high dry-basis concentration of syngas 36% (71%) with a low energy cost of 66kJ/mol (32kJ/mol) were achieved for simulated biogas reforming with air (pure O<SUB>2</SUB>) in this novel gliding arc reactor. In addition, in the oxidative reforming of simulated biogas, syngas production was shown to be largely attributed to the partial oxidation reaction, and the remarkable CO<SUB>2</SUB> conversion was solely attributed to the reverse water gas shift reaction.

3D Atom Probe Characterization of Temporal Evolution of Precipitates in Aging Nb-V Micro-Alloyed Steel

Q.D.Liu,W.Q.Liu,S.J.Zhao 대한금속·재료학회 2012 METALS AND MATERIALS International Vol.18 No.6

A 3D atom probe combined with TEM was applied to characterize carbides precipitation in Nb-V microalloyed steel aging at 550 °C for different times after being water-quenched from 1200 °C. The results indicated that the V- and Nb-containing ultra-fine carbides obtained by 4 h aging had the highest number density and moderate sizes, resulting in a peak precipitation strengthening value. C, V and Nb firstly co-segregated to form nano-sized clusters at the initial stage of precipitation, and then contributed to the formation of composition-steady carbides as the aging time was prolonged.

Combustion synthesis and photocatalytic properties of magnetically separable Zn_1-xCd_xS/γ-Fe₂O₃ composites

Liu, J.,Zhang, D.,Pu, X.,Dong, D.,Cai, P.,Seo, H.J. North-Holland 2014 Materials letters Vol.130 No.-

Magnetically separable Zn<SUB>1-x</SUB>Cd<SUB>x</SUB>S/γ-Fe<SUB>2</SUB>O<SUB>3</SUB> (x=0-1) photocatalysts were synthesized by a one-step combustion method. The structures, morphologies, absorbance, optical and photocatalytic properties of the samples were studied by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet-visible spectrophotometry and photoluminescence. The experimental results show that the formation of hexagonal Zn<SUB>1-x</SUB>Cd<SUB>x</SUB>S and γ-Fe<SUB>2</SUB>O<SUB>3</SUB> and the combination of them were one-pot achieved. The Cd<SUP>2+</SUP> content has a significant influence on the absorbance of visible light and fluorescence properties. The magnetic properties of samples ensure the magnetic separation by using a magnet. CdS/γ-Fe<SUB>2</SUB>O<SUB>3</SUB> shows the best photocatalytic performance compared with other samples, ascribed to its small energy band gap and matching energy band structure between CdS and γ-Fe<SUB>2</SUB>O<SUB>3</SUB>. Moreover, no obvious deterioration was observed in the stability tests.