160 research outputs found
Electrochemical Stimulation of PAH Biodegradation in Sediment
<div><p>Natural attenuation of PAH in sediments is usually slow due to prevailing anaerobic conditions in sediments. Electrochemical stimulation of PAH biodegradation is proposed and demonstrated for remediation of contaminated sediment. Two graphite electrodes were placed horizontally at different depths in PAH-spiked sediments; the cathode was near the water-sediment interface and the anode was laid in the deeper sediment. An external power of 2 V was continuously applied to the electrodes to stimulate PAH biodegradation. Redox potential around the anode in powered reactors increased gradually, and was 50–150 mV higher than that in the control. pH around the anode decreased to ∼6 from an initial value of 6.4 or 6.7 in powered reactors, which reflected water electrolysis. Phenanthrene concentration at the anode decreased with time, showing a unique Z-shaped profile in the sediment in powered reactors. PAH degrading genes around the anode in powered reactor were found to increase compared to the control reactor, which provided microbial evidence of biodegradation. These findings demonstrated the capability of this novel bioelectrochemical technology for the remediation of PAH-contaminated sediment.</p></div
DataSheet1_Dual-mode electrochemiluminescence and electrochemical sensor for alpha-fetoprotein detection in human serum based on vertically ordered mesoporous silica films.docx
In this study, we demonstrated the highly sensitive detection of alpha-fetoprotein (AFP) by electrochemiluminescence (ECL) and electrochemistry (EC) based on the gated transport of the bifunctional probe (tris(1,10-phenanthroline) ruthenium (II) chloride, Ru (phen)3Cl2) into the nanochannels of vertically ordered mesoporous silica films (VMSFs). Due to the negatively charged surface and ultrasmall pore size, VMSF displays a signal amplification effect on Ru (phen)3Cl2 and is suitable for the construction of sensors with excellent sensitivity. With the linkage of (3-glycidyloxypropyl) trimethoxysilane, the anti-AFP antibody could covalently bind to the external surface of VMSF, generating a highly specific recognized sensing interface toward AFP. When AFP is presented, the formed immunocomplex hinders the diffusion of Ru (phen)3Cl2 to the underlying electrode surface, resulting in a decreased ECL or EC response. The dual-mode detection of AFP is achieved with a relatively low limit of detection (0.56 fg/ml for ECL and 4.5 pg/ml for EC) and a wide linear range (10 fg/ml∼1 μg/ml for ECL and 10 pg/ml∼1 μg/ml for EC). Moreover, owing to the inherent anti-fouling property of VMSF, satisfactory results in the analysis of human serum were obtained, showing the great potential of the designed strategy in clinical diagnosis.</p
Highly Ordered Binary Assembly of Silica Mesochannels and Surfactant Micelles for Extraction and Electrochemical Analysis of Trace Nitroaromatic Explosives and Pesticides
The
rapid and sensitive detection of nitroaromatic compounds is of great
significance for human health, the environment, and public security.
The present work reports on the extraction and electrochemical analysis
of trace nitroaromatic compounds, such as explosives and organophosphate
pesticides (OPs), using the indium tin oxide (ITO) electrodes modified
with a highly ordered and aligned binary assembly of silica mesochannels
and micelles (BASMM). With a pore diameter of ca. 2–3 nm, silica
mesochannels (SMs) perpendicularly oriented to the ITO electrode surface
can provide hard and robust supports to confine the soft cylindrical
micelles formed by the aggregation of cationic surfactants, namely,
cetyltrimethylammonium bromide (CTAB). Due to the organized self-assembly
of hydrocarbon tails of CTAB surfactants, each micelle has a hydrophobic
core, which acts as an excellent adsorbent for rapid extraction and
preconcentration of trace nitroaromatic compounds from aqueous solutions
via the hydrophobic effect. Furthermore, the cylindrical micelles
are directly in contact with the underlying electrode surface, to
which extracted compounds can freely diffuse and then be reduced therein,
thus allowing their determination by means of voltammetry. Using the
BASMM/ITO sensor, electrochemical analysis of trace nitroaromatic
explosives, including 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenol,
2,6-dinitrotoluene, 3-nitrophenol, and nitrobenzene, and OPs, such
as paraoxon, methyl parathion, and fenitrothion, was achieved with
a fast response, wide linear range, high sensitivity, and low detection
limit at the ppb level. TNT and paraoxon in real apple, tea, and water
samples were also determined. By combining the heterogeneous extraction
and determination in one ordered binary nanostructure, the BASMM sensor
provides a very simple, rapid, and cost-effective way for analysis
of nitroaromatic compounds and can be extended to a wide range of
lipophilic yet redox-active analytes
Enhanced terahertz frequency mixing in all-dielectric metamaterial with multiple surface plasmon polaritons resonances
Nonlinear metamaterials hold a promising platform for generating terahertz (THz) waves. In this paper, we present an all-dielectric metamaterial with multiple surface plasmon polariton (SPP) resonances for enhanced THz frequency mixing. The metamaterial is composed of graphene ribbons, a dielectric layer, and a one-dimensional photonic crystal, displaying the multiple absorptions with simultaneous excitation of three SPP resonances. Taking advantage of SPP resonances with high Q factor and strong localized field at the input frequency, the third-order nonlinear processes are remarkably enhanced, including third-harmonic generation (THG) and four-wave mixing (FWM), producing a variety of frequencies in the THz range. The proposed efficient nonlinear metamaterials offer promising applications for THz frequency synthesis
Data_Sheet_1_Case report: Methicillin-resistant Staphylococcus aureus with penicillin susceptible (PS-MRSA): first clinical report from a psychiatric hospital in China.CSV
This case report documents the first instance of Penicillin-Susceptible Methicillin-Resistant Staphylococcus aureus (PS-MRSA) in a Chinese psychiatric hospital. The strain was isolated from a patient with Alzheimer’s disease who had a lower respiratory tract infection. Clinical and laboratory analyses, including mass spectrometry, antibiotic susceptibility testing, and whole-genome sequencing, confirmed the PS-MRSA strain. In this case, we systematically introduce the clinical symptoms, laboratory findings, and treatment responses associated with this PS-MRSA strain. This discovery offers a new perspective on our understanding of resistance mechanisms and expands our considerations for existing antibiotic treatments. It may fill a gap in the classification of MRSA strains, enhance the spectrum of MRSA resistance, and complete the therapeutic strategies for MRSA.</p
Acoustic Delivery of Plasma Low-Density Lipoprotein into Liver via ApoB100-Targeted Microbubbles Inhibits Atherosclerotic Plaque Growth
Atherosclerosis
is the main risk factor for cardiovascular disease,
which accounts for the majority of mortality worldwide. A significantly
increased plasma level of low-density lipoprotein cholesterol (LDL-C),
surrounded by a monolayer of phospholipids, free cholesterol, and
one apolipoprotein B-100 (ApoB-100) in the blood, plays the most significant
role in driving the development of atherosclerosis. Commercially available
cholesterol-lowering drugs are not sufficient for preventing recurrent
cardiovascular events. Developing alternative strategies to decrease
the plasma cholesterol levels is desirable. Herein, we develop an
approach for reducing LDL-C levels using gas-filled microbubbles (MBs)
that were coated with anti-ApoB100 antibodies. These targeted MBApoB100 could selectively capture LDL particles in the bloodstream
through forming LDL-MBApoB100 complexes and transport them
to the liver for degradation. Further immunofluorescence staining
and lipidomic analyses showed that these LDL-MBApoB100 complexes
may be taken up by Kupffer cells and delivered to liver cells and
bile acids, greatly inhibiting atherosclerotic plaque growth. More
importantly, ultrasound irradiation of these LDL-MBApoB100 complexes that accumulated in the liver may induce acoustic cavitation
effects, significantly enhancing the delivery of LDL into liver cells
and accelerating their degradation. Our study provides a strategy
for decreasing LDL-C levels and inhibiting the progression of atherosclerosis
The Ability of PVX p25 to Form RL Structures in Plant Cells Is Necessary for Its Function in Movement, but Not for Its Suppression of RNA Silencing
<div><p>The p25 triple gene block protein of <em>Potato virus X</em> (PVX) is multifunctional, participating in viral movement and acting as a suppressor of RNA silencing. The cell-to-cell movement of PVX is known to depend on the suppression function of p25. GFP-fused p25 accumulates in rod-like (RL) structures with intense fluorescence in cells. By monitoring the location of fluorescence at different times, we have now shown that the RL structure is composed of filaments. P25 mutants without the conditional ability to recover movement function could not form RL structures while the mutants that had the ability did form the structure, suggesting that the ability of p25 to form RL structures is necessary for its function in cell-to-cell movement, but not for its suppressor function. Moreover, chemical inhibition of microfilaments in cells destroyed the formation of the complete RL structure. Additionally, TGBp2 and TGBp3 were recruited into the RL structure, suggesting a relationship between the TGBps in virus movement.</p> </div
Supplementary document for Maximum chirality of THz metasurfaces with quasi-bound states in the continuum - 6877217.pdf
Supplementary document forMaximum chirality of THz metasurfaces with quasi-bound states in the continuum-51923
Additional file 1: Table S1. of Integrated care reform in urban China: a qualitative study on design, supporting environment and implementation
An overview of health resources in Hangzhou (2013). Table S2a. Characteristics of the sampled key informants in FGDs. Table S2b. Characteristics of the sampled key informants in IDIs. Table S3. The detailed points for probing in topic guides. (DOCX 28 kb
Diagram showing the plasmids used in this work.
<p>Plamsids were constructed into the pCV1300 binary vector that was developed from pCAMBIA1300 with the CaMV 35S promoter.</p
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