Ionic blockade in a charged single-file water channel

The classical continuum theories fail to describe the ionic transport in Angstrom channels, where conduction deviates from Ohm's law, as attributed to dehydration/self-energy barrier and dissociation of Bjerrum ion-pairs in previous work. Here we found that the cations are strongly bound to the surface charge that blockade the ionic transport in a single-file water channel, causing nonlinear current-voltage responses. The presence of free ions significantly increased the probability of bound ions being released, resulting in an ionic current. We found that ionic conduction gradually becomes Ohmic as surface charge density increases, but the conduction amplitude decreased due to increased friction from bound ions. We rationalized the ionic transport by 1D Kramers' escape theory framework, which well described nonlinear ionic current, and the impact of surface charge density on turning to Ohmic system. Our results possibly provide an alternative view of ionic blockade in Angstrom channels

The current system associated with the boundary of plasma bubbles

The current system associated with the boundary of plasma bubbles in the Earth's magnetotail has been studied by employing Cluster multipoint observations. We have investigated the currents in both the dipolarization front (DF, leading edge of the plasma bubble) and the trailing edge of the plasma bubble. The distribution of currents at the edge indicates that there is a current circuit in the boundary of a plasma bubble. The field‐aligned currents in the trailing edge of the plasma bubble are flowing toward the ionosphere (downward) on the dawnside and away from the ionosphere (upward) on the duskside, in the same sense as region‐1 current. Together with previous studies of the current distributions in the DF and magnetic dip region, we have obtained a more complete picture of the current system surrounding the boundary of plasma bubble. This current system is very similar to the substorm current wedge predicted by MHD simulation models but with much smaller scale.Key PointsWe have obtained a current circuit in the boundary of plasma bubbleThe FACs in the trailing edge of plasma bubble is also region‐1‐senseThe current and FACs system is similar to SCW but with much smaller scalePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110641/1/grl52338.pd

Liquid-solid slip on charged walls: dramatic impact of charge distribution

Nanofluidic systems show great promises for applications in energy conversion, where their performance can be enhanced by nanoscale liquid-solid slip. However, efficiency is also controlled by surface charge, which is known to reduce slip. Combining molecular dynamics simulations and analytical developments, we show the dramatic impact of surface charge distribution on the slip-charge coupling. Homogeneously charged graphene exhibits a very favorable slip-charge relation (rationalized with a new theoretical model correcting some weaknesses of the existing ones), leading to giant electrokinetic energy conversion. In contrast, slip is strongly affected on heterogeneously charged surfaces, due to the viscous drag induced by counter-ions trapped on the surface. In that case slip should depend on the detailed physical chemistry of the interface controlling the fraction of bound ions. Our numerical results and theoretical models provide new fundamental insight on the molecular mechanisms of liquid-solid slip, and practical guidelines for searching new functional interfaces with optimal energy conversion properties, e.g. for blue energy or waste heat harvesting.Comment: Main text: 7 pages, 3 figures; supplemental material: 22 pages, 5 figures; to be published in Physical Review Letter

Comparison of long-term radial artery occlusion following trans-radial coronary intervention using 6-french versus 7-french sheaths

Background: The aim of this study was to explore the impact of 6-Fr and 7-Fr sheaths on the incidenceof long-term radial artery occlusion (RAO) after trans-radial coronary intervention (TRI).Methods: From September 2013 to January 2016, patients with ischemic heart disease includingacute myocardial infarction and true bifurcation lesions were randomly assigned to 6-Fr group and7-Fr group immediately after coronary angiography in a 1:1 ratio. The radial artery diameters wereobserved by ultrasound examination one day prior to TRI as well as at 30 days and 1 year after TRI.The primary endpoint was the incidence of RAO at 1-year after TRI. The secondary endpoints were theincidence of local vascular complications during hospitalization and changes of radial artery diameterswithin 1-year after TRI between the two groups. Additionally, multivariate logistic regression analysiswas used to explore potential factors related to the incidence of long-term RAO after TRI.Results: A total of 214 patients were enrolled and randomly assigned to 6-Fr group (n = 105) or7-Fr group (n = 109). There was no significant difference in the incidence of RAO at 1-year after TRI(8.57% vs. 12.84%, p = 0.313). Moreover, no significant difference was observed in the incidence of localvascular complications during hospitalization (20% vs. 24.77%, p = 0.403). After 1-year follow-up,no significant difference was found in radial artery diameters (2.63 ± 0.31 mm vs. 2.64 ± 0.27 mm,p = 0.802). Multivariate logistic analysis revealed that repeated TRI was an independent risk factor oflong-term RAO 1 year after TRI (OR = 10.316, 95% CI 2.928–36.351, p = 0.001).Conclusions: Compared to 6-Fr sheath, 7-Fr sheath did not increase short-term or long-term incidenceof RAO after TRI

Differential protein expression of Caco-2 cells treated with selenium nanoparticles compared with sodium selenite and selenomethionine

The study was designed to determine the differential protein expression of Caco-2 cells treated with different forms of selenium including sodium selenite, selenomethionine (Se-Met), and selenium nanoparticles (nano-Se). Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS) were used to identify the differentially expressed proteins. The results indicated that seven protein spots, ubiquitin-conjugating enzyme E2 (E2), glutathione synthetases (GS), triosephosphate isomerase (TSP), T-complex protein 1 subunit zeta (TCPZ), lamin-B1, heterogeneous nuclear ribonucleoprotein F (hnRNP F), and superoxide dismutase [Cu-Zn] (Cu, Zn-SOD) were significantly different among all the groups. According to the order of control, sodium selenite, Se-Met, and Nano-Se, the expression levels of two proteins (E2 and GS) increased and the other differential proteins were reverse. Except for E2, there were no significant differences in other protein expressions between the groups treated with nano-Se and Se-Met

Characterization of Adenocarcinoma\u27s Autofluorescence Properties Using Multiexcitation Analysis Method

General purpose of this research is to get an early cancer detection method based on the properties of optical analysis between normal and adenocarsinoma tissue using the multiexcitation autofluorescence method. Observation of autofluorescence properties was done on the biopsy sample of adenocarcinoma tissues, GR mice transplanted by adenocarsinoma, and cell culture SM 1. Excitation on tissue was done by using  the lamp Light Emitting Diode (LED) at some visible light wavelength range. This research obtained that the value of Intensity Auto fluorescence (IAF) at range red wavelength of cells and adenocarsinoma tissues tend to lower compared to the cells normal tissues if its were excited by blue LED. On the contrary, the value of IAF at infra red wavelength from cells and carcinoma tissues tend to higher compared to the cells and normal tissues if its were excited by red LED

Ion-Exchange Chromatography Coupled With Dynamic Coating Capillary Electrophoresis for Simultaneous Determination of Tropomyosin and Arginine Kinase in Shellfish

Tropomyosin (TM) and arginine kinase (AK) are known as two major allergens in seafood. For the first time, we demonstrate a newly developed ion-exchange chromatography coupled with dynamic coating capillary electrophoresis (IEC-DCCE) method to simultaneously analyze the TM and AK in shellfish. First, we have optimized the procedure of IEC for simple enrichment of TM and AK crude extract. By using 30 mM borate-borax at pH 9.0 with 0.3% (v/v) Tween-20 as a dynamic coating modifier for capillary electrophoresis (CE) separation, the migration time, separation efficiency and electrophoretic resolution greatly improved. The limits of detection (LOD) were 1.2 μg mL−1 for AK and 1.1 μg mL−1 for TM (S/N = 3), and the limits of quantification (LOQ) were 4.0 μg mL−1 for AK and 3.7 μg mL−1 for TM (S/N = 10). The recovery of AK ranged from 91.5 to 106.1%, while that of TM ranged from 94.0 to 109.5%. We also found that only when the concentrations of AK and TM were above LOD reported here, these proteins can stimulate human mast cell (LAD2) degranulation. Finally, the use of IEC-DCCE to analyze fresh shellfish samples highlights the applicability of this method for the simultaneous detection of these allergens in complex food systems

Optimization of LTE Network Coverage

The trend of mobile, broadband and IP is becoming more and more prominent. Mobile communication technology is now in acritical period in the evolution of network technology. As such, LTE (Long Term Evolution) comes to light. LTE serves as a unified standardfor the new generation of mobile communications, equipped with high spectral efficiency, high peak rate, high mobility, flat networkarchitecture and other advantages. Huawei has played a very important role in the commercialization of LTE. As a sponsor of NGMN,Huawei has been actively involved in the research of some key projects of NGMN, such as network self-optimization, system architectureand Network performance evaluation and so on. This paper mainly introduces the problems encountered in the optimization of LTEnetwork coverage, the practical problems encountered by the LTE project team in Qingdao and the analysis and solutions to the problems.At the same time, this paper discusses in detail on the LTE network optimization process

Comparison of long-term radial artery occlusion following trans-radial coronary intervention using 6-french versus 7-french sheaths

BACKGROUND: The aim of this study was to explore the impact of 6-Fr and 7-Fr sheaths on the incidence of long-term radial artery occlusion (RAO) after trans-radial coronary intervention (TRI). METHODS: From September 2013 to January 2016, patients with ischemic heart disease including acute myocardial infarction and true bifurcation lesions were randomly assigned to 6-Fr group and 7-Fr group immediately after coronary angiography in a 1:1 ratio. The radial artery diameters were observed by ultrasound examination one day prior to TRI as well as at 30 days and 1 year after TRI. The primary endpoint was the incidence of RAO at 1-year after TRI. The secondary endpoints were the incidence of local vascular complications during hospitalization and changes of radial artery diameters within 1-year after TRI between the two groups. Additionally, multivariate logistic regression analysis was used to explore potential factors related to the incidence of long-term RAO after TRI. RESULTS: A total of 214 patients were enrolled and randomly assigned to 6-Fr group (n = 105) or 7-Fr group (n = 109). There was no significant difference in the incidence of RAO at 1-year after TRI (8.57% vs. 12.84%, p = 0.313). Moreover, no significant difference was observed in the incidence of local vascular complications during hospitalization (20% vs. 24.77%, p = 0.403). After 1-year follow-up, no significant difference was found in radial artery diameters (2.63 ± 0.31 mm vs. 2.64 ± 0.27 mm, p = 0.802). Multivariate logistic analysis revealed that repeated TRI was an independent risk factor of long-term RAO 1 year after TRI (OR = 10.316, 95% CI 2.928–36.351, p = 0.001). CONCLUSIONS: Compared to 6-Fr sheath, 7-Fr sheath did not increase short-term or long-term incidence of RAO after TRI

Micro-/nanobubble oxygenation irrigation enhances soil phosphorus availability and yield by altering soil bacterial community abundance and core microbial populations

Micro-/nanobubble oxygenation irrigation, as a novel irrigation technique, has been widely utilized to enhance soil phosphorus availability and maize yield. Nevertheless, currently, most of the studies remain unclear about the precise mechanism through which micro-/nanobubble oxygenation improves soil phosphorus availability and maize yield. Therefore, we established two irrigation methods, conventional irrigation (CF) and micro-/nanobubble oxygenation irrigation (MB), to investigate the combined effects on enzyme activity, microbial communities, and soil phosphorus availability in the rhizosphere soil of maize.The results showed that compared to the CF treatment, the MB treatment significantly increased available phosphorus content and alkaline phosphatase activity in maize rhizosphere soil by 21.3% and 15.4%, respectively. Furthermore, MB significantly influenced bacterial diversity in the maize rhizosphere soil but did not considerably affect fungal diversity. Specifically, MB regulated the microbial community structure in the maize rhizosphere by altering the relative abundances of the bacterial phylum Firmicutes and the fungal phyla Mucoromycota, Chytridiomycota, and Basidiomycota. In addition, MB reduced the complexity of the bacterial network while increasing the interaction density among bacterial species. Meanwhile, MB enhanced the complexity of the fungal network. Structural equation modeling indicated that MB primarily promoted soil alkaline phosphatase activity by regulating bacterial community diversity, thereby enhancing soil phosphorus availability. In conclusion, the application of micro-/nanobubble oxygenation irrigation enhances the activity of alkaline phosphatasein the soil by modulating the microbial community within the rhizosphere, thereby facilitating increased phosphorus availability in the rhizosphere of maize