16 research outputs found
Optimization of Operating Parameters for Low NO<sub><i>x</i></sub> Emission in High-Temperature Air Combustion
This paper focuses on determining the effects of operating
parameters
on NO<sub><i>x</i></sub> emission and parameters optimization
to reduce NO<sub><i>x</i></sub> emission for high-temperature
air combustion furnaces. For this purpose, the Taguchi method, based
on computational fluid dynamics (CFD) modeling, was implemented. Eight
factors were considered, including the velocity of air injection (A),
the velocity of fuel injection (B), the oxygen concentration in preheated
air (C), the preheated air temperature (D), fuel temperature (E),
the interaction between A and B, the interaction between A and C,
and the interaction between A and D. An L<sub>27</sub> (3<sup>13</sup>) orthogonal array was employed to arrange the CFD modeling tests.
By analysis of variance, the degrees of effect of the selected factors
are determined, which are as follows, in descending order: E, B, C,
A, D, AB, AC, and AD. The major factors are found to be A, B, C, and
E, while the other factors are considered to be secondary factors.
The optimal operating conditions are determined to be A = 120 m/s,
B = 85 m/s, C = 18.5%, D = 1493 K, and E = 298 K. Under the optimal
operating condition, the concentration of NO<sub><i>x</i></sub> emission decreases by 25.45%, compared with the original operating
condition
Iridium-Catalyzed Asymmetric Ring-Opening of Azabicyclic Alkenes with Phenols
The asymmetric ring-opening of azabicyclic alkenes with
a variety of phenols is investigated using an iridium catalyst generated
in situ from 2.5 mol % of [IrÂ(COD)ÂCl]<sub>2</sub> and 5.0 mol % of
(<i>S</i>)-BINAP, which afforded the corresponding 1,2-<i>trans</i>-phenoxyamino products in excellent yield (up to 92%)
with moderate to good enantioselectivities (up to 98% ee). The <i>trans</i>-configuration of the product <b>4b</b> was confirmed
by X-ray crystallography
Discrimination of five <i>Ebolavirus</i> species by gel electrophoresis of PCR fragments.
<p>Plasmids of the five <i>Ebolavirus</i> species (<i>Zaire</i>, <i>Sudan</i>, <i>Reston</i>, <i>Taï Forest</i> and <i>Bundibugyo</i>), a mixture of all five, and negative controls were tested in the one-step FRET-PCR system established in this study. Amplicons obtained were electrophoresed through a 4% agarose gel and stained with SYBR Safe Gel stain (SYBR Safe DNA Gel Stain, Invitrogen, USA). The different sizes of the PCR products of each species (255 bp, 211 bp, 192 bp, 166 bp and 146 bp) were visualized alongside a 20bp DNA ladder (Thermo Scientific O’RangeRuler 20 bp DNA Ladder, Ready-to-use, Thermo Scientific, USA).</p
Alignment of primers and probes for five <i>Ebolavirus</i> species.
<p>Nucleotide sequences of the primers (one forward primer and five reverse primers for all <i>Ebolavirus</i> species) and probes are shown at the top of the frames while the corresponding nucleotide sequences of five species of <i>Ebolavirus</i> are shown at the bottom. Dots indicated that nucleotides are identical to those of primers/probes, and strips indicated deletion of nucleotides. The upstream primer was used as shown while the downstream primers and probes were used as reverse oligonucleotides. The 6-FAM and LCRed-640 probes had 5 and 1 degenerate nucleotides, respectively. The numbers associated with primers/probes indicate the positions of primers/probes in the whole genome of <i>Ebolavirus</i>.</p
The sensitivity, melting curve analysis and gel electrophoresis of the one-step RT-FRET-PCR performed on <i>Ebolavirus</i> RNA-containing VLPs.
<p>The amplification curves of 100 copies of VLPs containing each of these five <i>Ebolavirus</i> species were run in the RT FRET PCR established in this study (<b>A</b>), followed by melting curves analysis (<b>B</b>) and gel electrophoresis (<b>C</b>). The Amplification curves of reverse-transcription PCR on serially diluted VLPs inoculated in blood sample showed similar sensitivity as in blood samples spiked with transcribed RNA (data not shown).</p
PCR amplification curves of serially diluted plasmids containing each of five <i>Ebolavirus</i> species.
<p>The plasmid quantitative standards (10<sup>4</sup>, 10<sup>3</sup>, 10<sup>2</sup>, 10<sup>1</sup>, 10<sup>0</sup> /10μl) containing sequences of <i>Zaire ebolavirus</i> (<b>A</b>), <i>Sudan ebolavirus</i> (<b>B</b>), <i>Reston ebolavirus</i> (<b>C</b>), <i>Taï Forest ebolavirus</i> (<b>D</b>), <i>Bundibugyo ebolavirus</i> (<b>E</b>) and negative control were detected by the one-step reverse transcription FRET-PCR established in this study. The detection sensitivity was one copy per reaction system.</p
Transduction efficiency after intramyocardial injection of NGF siRNA <i>in vivo</i>.
<p>(A) Representative site of intramyocardial injection (arrowed) and GFP expression in infarcted hearts of rats in the MI-SiNGF group at 1 wk time point. (B) Relative expressions of NGF mRNA, detected by real-time quantitative RT-PCR, in the sham-operated, MI-control, MI-GFP and MI-SiNGF groups at various time points (1, 2, 4 and 8 wk) after intramyocardial injection of NGF siRNA. Relative gene expressions of NGF were analyzed by the 2<sup>-ΔΔCT</sup> method taking those in the sham-operated groups as 1. (C) Expressions of NGF (27 KDa) and GAPDH (36 KDa), analyzed by Western blot, in the sham-operated, MI-control, MI-GFP and MI-SiNGF groups at various time points (1, 2, 4 and 8 wk) after intramyocardial injection of NGF siRNA. (D) Relative protein expressions of NGF. The protein expression levels in (C) were quantified with Quantity AlphaEaseFCTM imaging software. Relative expression of NGF was normalized to GAPDH. Data were presented as mean ± SD. *<i>p<0.05</i> MI-control group vs. sham-operated groups, †<i>p<0.05</i> MI-SiNGF group vs. MI-control or MI-GFP groups. The results showed that expression levels of NGF mRNA and protein were induced in the MI-control group compared to the sham-operated group. NGF mRNA and protein in the MI-GFP group had no significant levels compared to the MI-control group, while those in the MI-SiNGF group were reduced compared to the MI-GFP group.</p
Histological and RT-PCR results of TH- and GAP 43 expression.
<p>Data were expressed as means ± SD.</p><p>* <i>P<0.05</i> vs. Sham-operated group;</p>†<p><i>P<0.05</i> vs. MI-GFP group.</p
Target Elucidation by Cocrystal Structures of NADH-Ubiquinone Oxidoreductase of <i>Plasmodium falciparum</i> (<i>Pf</i>NDH2) with Small Molecule To Eliminate Drug-Resistant Malaria
Drug-resistant
malarial strains have been continuously emerging
recently, which posts a great challenge for the global health. Therefore,
new antimalarial drugs with novel targeting mechanisms are urgently
needed for fighting drug-resistant malaria. NADH-ubiquinone oxidoreductase
of <i>Plasmodium falciparum</i> (<i>Pf</i>NDH2)
represents a viable target for antimalarial drug development. However,
the absence of structural information on <i>Pf</i>NDH2 limited
rational drug design and further development. Herein, we report high
resolution crystal structures of the <i>Pf</i>NDH2 protein
for the first time in Apo-, NADH-, and RYL-552 (a new inhibitor)-bound
states. The <i>Pf</i>NDH2 inhibitor exhibits excellent potency
against both drug-resistant strains in vitro and parasite-infected mice in vivo via a potential allosteric mechanism.
Furthermore, it was found that the inhibitor can be used in combination
with dihydroartemisinin (DHA) synergistically. These findings not
only are important for malarial <i>Pf</i>NDH2 protein-based
drug development but could also have broad implications for other
NDH2-containing pathogenic microorganisms such as <i>Mycobacterium
tuberculosis</i>
Representative images for infarcted hearts at 8 wk time point after MI.
<p>(A) Macroscopical view of the infarcted heart. (B) Masson’s trichrome staining of infarcted area.</p