193 research outputs found
The effects of various feeding protocols on oxidative stress status in the brain.
<p>Seven-week old male mice had free access to regular chow or high fat diet or were allowed to have free access to regular chow every other day (intermittent fasting) for 11 months. Their brains were then harvested to measure glutathione (GSH), glutathione disulfide (GSSG), 4-hydroxy-2-nonenal (HNE) and nitrotyrosine containing proteins. The levels of GSH and GSSG and ratio of GSH/GSSG in the cerebral cortex and hippocampus are presented in panels A and B, respectively. The levels of HNE and nitrotyrosine containing proteins in the cerebral cortex and hippocampus are shown in the panels C and D. Results are means ± S.E.M (n = 8). * P<0.05 compared with mice on regular chow <i>ad libitum</i>.</p
Designing Difunctional Promoters for Hypergolic Ignitions of Green Bipropellants Combining Ionic Liquids with H<sub>2</sub>O<sub>2</sub>
The
emergence of tetrahydroborate (BH4–)/cyanoborohydride
(BH3CN–) anion-based
ionic liquid fuels in combination with high test peroxide (>90%H2O2, HTP) oxidizers has accelerated the greening
of bipropellants. However, most BH4– and
BH3CN– anion-based ionic liquids are
sensitive to water, making it difficult to store them. Here, novel
difunctional promoters are designed for hypergolic ignition of BH4–/BH3CN– anion-free
ionic liquids with 90%H2O2. The transition metal
in anions of promoters is expected to catalyze the exothermic decomposition
of H2O2, and the substituted borohydride in
cations of promoters acts as the ignition source. These novel difunctional
promoters show good solubility in commercially available 1-allyl-3-methylimidazolium
dicyanamide and 1-butyl-3-methylimidazolium dicyanamide ionic liquid
fuels, and the composite fuels exhibit high density, acceptable viscosity,
and high thermostability. The addition of difunctional promoters ensures
the smooth hypergolic ignition of BH4–/BH3CN– anion-free ionic liquid fuels
with a minimum ignition delay time of 34.0 ms, and no apparent microexplosion
and secondary combustion are observed during the ignition process.
With the increase in the amount of the promoter, density specific
impulses of the composite fuels improve gradually. This work provides
a platform strategy for designing promoters by synergy of cations
and anions and makes efforts to seek green bipropellants
The effects of various feeding protocols on CA1 pyramidal cell layer thickness, neuron-specific proteins and brain derived neurotrophic factor (BDNF) in the brain.
<p>Seven-week old male mice had free access to regular chow or high fat diet or were allowed to have free access to regular chow every other day (intermittent fasting) for 11 months. Their brains were then harvested to measure CA1 pyramidal cell layer thickness (panel A) and expression of NeuN, drebrin and synaptophysin in the cerebral cortex (panel B) and hippocampus (panel C) as well as the BDNF levels in the cerebral cortex and hippocampus (panel D). The protein abundance results in each mouse were normalized by the mean value of the corresponding protein in the regular diet-fed mice. Results are means ± S.E.M (n = 7 – 12). * P<0.05 compared with mice on regular diet ad libitum. GAPDH: glyceraldehydes 3-phosphate dehydrogenase; Hippo: hippocampus; SP: synaptophysin; RD: regular diet; IF: intermittent fasting; HFD: high fat diet.</p
Potential of High Load Extension for Gasoline HCCI Engine Using Boosting and Exhaust Gas Recirculation
Homogeneous charge compression ignition (HCCI) still faces challenges in high load extension. In this paper, HCCI high load operation range was extended and combustion phasing was controlled by boosting combined with internal EGR and external EGR in a gasoline HCCI engine. Internal EGR was obtained by negative valve overlap (NVO) and used to achieve gasoline HCCI at ambient temperature without intake heating. Combustion phasing was optimized by adjusting the external EGR inducted into the intake system. The experimental results show that both boosting and EGR are effective means for HCCI high load extension but with limitations of peak pressure (<i>P</i><sub>max</sub>), maximum rate of pressure rise (<i>R</i><sub>max</sub>), combustion efficiency (η<sub>c</sub>), and NO<sub><i>x</i></sub> emissions. Under the acceptable <i>P</i><sub>max</sub>, <i>R</i><sub>max</sub>, η<sub>c</sub>, and NO<sub><i>x</i></sub> levels of a production gasoline engine, the achievable maximum IMEP is in the following order: external EGR, boosting, boosting combined with EGR. With increasing boost pressure, NO<sub><i>x</i></sub> emissions are significantly reduced. But with acceptable <i>P</i><sub>max</sub>, heavy boosting leads to an ultralean mixture, followed by uncompleted combustion, which results in CO and HC emissions. At a fixed NVO, there is an appropriate range of the external EGR rate for stable HCCI combustion without knocking or misfire. Therefore, the optimized path was achieved using various internal EGR and external EGR combined to extend HCCI high load operation range. In addition, it can be found that boost pressure, percentage of CO<sub>2</sub> addition, and internal and external EGR rate have shown significant effects on combustion phasing of HCCI
Additional file 3 of Genome-wide identification and characterization of AP2/ERF gene superfamily during flower development in Actinidia eriantha
Additional file 3: Table S3. The basic information of AP2/ERF gene family in A. eriantha and A. chinensis
Production of Biodiesel by Esterification of Stearic Acid over Aminophosphonic Acid Resin D418
Biodiesel production has become a very intense research
field because
of its environmental benefits and the growing interest in finding
new resources and alternatives for conventional fuels. In the present
work, biodiesel production from the esterification of the free fatty
acid stearic acid with ethanol over aminophosphonic acid resin D418
was studied. The effects of experimental factors such as the amount
of D418, reaction temperature, and molar ratio of ethanol to stearic
acid on the conversion ratio were evaluated. Process optimization
using response surface methodology (RSM) was performed, and the interactions
between the operating variables were elucidated. The optimum values
for maximum esterification percentage were obtained by using a Box–Behnken
center-united design with a minimum of experimental work. Moreover,
the kinetics of the esterification catalyzed by D418 was studied,
and the pseudohomogeneous (PH) model was used to simulate the experimental
data
Time-Dependent Surface Structure Evolution of NiMo Films Electrodeposited Under Super Gravity Field as Electrocatalyst for Hydrogen Evolution Reaction
The
surface structures of the electrodeposited NiMo films from
compact to porous structure are adjusted by the combination of gravity
acceleration and electrodeposition time. The evolution mechanism of
surface structure is discussed based on the protrusion growth theory.
The dependence of catalytic activity of the NiMo films for hydrogen
evolution reaction (HER) on surface structure evolution is studied.
The results indicate that compact NiMo layer is first electrodeposited,
and then protrusions are formed. Finally, the protrusions rapidly
grow and form a porous structure. It is found that only the compact
NiMo films are electrodeposited under normal gravity condition due
to a long induced time for the protrusions formation. Under super
gravity field, the induced time for the protrusions formation is only
less than 5 min owing to the enhanced mass transfer by the gravity-induced
convection and hydrogen bubble agitation convection. So, a porous
structure is easily formed under high gravity acceleration and long
electrodeposition time. The HER activities of NiMo films are improved
with the surface structure evolution from compact to porous structure
due to the increase of active area. All NiMo films exhibit a good
long-term durability, and the cell voltage of water electrolysis on
porous NiMo films is lower
Vaginoplasty with Acellular Dermal Matrix after Radical Resection for Carcinoma of the Uterine Cervix
<p>Various methods are available for vaginoplasty, but many of them have the drawbacks including surgical complexity and postoperative pain at the donor site. We herein evaluated the outcomes of vaginoplasty using tissue-engineered biomaterial graft. This study included 16 early stage cervical cancer patients who received curative surgery in combination with radiotherapy. They underwent vaginoplasty with tissue-engineered biological material, acellular dermal matrix (ADM). After treatment, a vaginal dilator was advised to be used for 6 months to prevent contraction of vagina. The effectiveness of the treatment was evaluated by the anatomic changes of vagina before and after treatment, and the sexual outcomes at 12-month after treatment. The procedure was safe with no intra-operative complications reported. The mean operation time was 1.7 ± 0.3 hours, with 11/16 patients had blood loss < 50 mL during surgery. Generally, epithelialization was observed in 2-week after treatment. At the 1-year follow-up visit, the mean vaginal width was increased significantly from 1.31 ± 0.4 cm before surgery to 4.13 ± 0.43 cm after surgery (p = 0.034). The vaginal length was also increased from 5.97 ± 0.59 cm to 9.25 ± 0.66 cm (p < 0.001). Majority of the patients (12/16) reported satisfactory sexual life. The use of ADM in vaginoplasty was a safe and effective procedure that provided satisfactory sexual function for patients with vaginal abnormalities after cervical cancer treatment.</p
Metal–Organic Framework Derived Magnetic Nanoporous Carbon: Novel Adsorbent for Magnetic Solid-Phase Extraction
The fabrication of a magnetic nanoporous
carbon (MNPC) via one-step
direct carbonization of Co-based metal–organic framework has
been achieved without using any additional carbon precursors. The
morphology, structure, and magnetic behavior of the as-prepared Co-MNPC
were characterized by using the techniques of scanning electron microscopy,
transmission electron microscopy, powder X-ray diffraction, Raman
spectroscopy, N<sub>2</sub> adsorption, and vibrating sample magnetometer.
The Co-MNPC has a high specific surface area, large pore volume, and
super paramagnetism. Its performance was evaluated by the magnetic
solid-phase extraction of some neonicotinoid insecticides from water
and fatmelon samples followed by high-performance liquid chromatographic
analysis. The effects of the main experimental parameters that could
affect the extraction efficiencies were investigated. The results
demonstrated that the Co-MNPC had an excellent adsorption capability
for the compounds
Covalent Bonding of Metal–Organic Framework-5/Graphene Oxide Hybrid Composite to Stainless Steel Fiber for Solid-Phase Microextraction of Triazole Fungicides from Fruit and Vegetable Samples
A hybrid
material of the zinc-based metal–organic framework-5
and graphene oxide (metal–organic framework-5/graphene oxide)
was prepared as a novel fiber coating material for solid-phase microextraction
(SPME). The SPME fibers were fabricated by covalent bonding via chemical
cross-linking between the coating material metal–organic framework-5/graphene
oxide and stainless steel wire. The prepared fiber was used for the
extraction of five triazole fungicides from fruit and vegetable samples.
Gas chromatography coupled with microelectron capture detector (GC-ÎĽECD)
was used for quantification. The developed method gave a low limit
of detection (0.05–1.58 ng g<sup>–1</sup>) and good
linearity (0.17–100 ng g<sup>–1</sup>) for the determination
of the triazole fungicides in fruit and vegetable samples. The relative
standard deviations (RSDs) for five replicate extractions of the triazole
fungicides ranged from 3.7 to 8.9%. The method recoveries for spiked
fungicides (5, 20, and 50 ng g<sup>–1</sup>) in grape, apple,
cucumber, celery cabbage, pear, cabbage, and tomato samples were in
the range of 85.6–105.8% with the RSDs ranging from 3.6 to
11.4%, respectively, depending on both the analytes and samples. The
metal–organic framework-5/graphene oxide coated fiber was stable
enough for 120 extraction cycles without a significant loss of extraction
efficiency. The method was suitable for the determination of triazole
fungicides in fruit and vegetable samples
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