170 research outputs found
COMPARATIVE RESEARCH ON THE STROKE RHYTHM OF MEN AND WOMEN KAYAKERS IN THE INTERNATIONAL COMPETITION
The text studied the stroke rate and rhythm of men and women kayakers in the world cup competition on the base of defined division of time phase for each stroke. It is found that the time proportion of the pull and air-work phase in the two sides of men kayakers are both 65% to 35%, while the time proportion of the same phase in the right-side of women kayakers is 66% to 34%, and that in the lefl-side is 69% to 31%; the power time proportion in the right-side of men kayakers is 40% and in the left-side is 41 %, while that in the right-side of women kayakers is 39% and in the lefl-side is 41 %. Men kayakers command a better symmetry and consistency between the left and right side in stroke rhythm than women kayakers. Men kayakers increase the stroke rate mainly accompanied with shortening the air-work time proportion while womenkayakers mainly with shortening the pull time proportion
Highly secretory expression of recombinant cowpea chlorotic mottle virus capsid proteins in Pichia pastoris and in-vitro encapsulation of ruthenium nanoparticles for catalysis
The applications of viral protein cages have expanded rapidly into the fields of bionanotechnology and materials science. However, the low-cost production of viral capsid proteins (CPs) on a large scale is always a challenge. Herein, we develop a highly efficient expression system by constructing recombinant Pichia pastoris cells as a “factory” for the secretion of soluble cowpea chlorotic mottle virus (CCMV) CPs. Under optimal induction conditions (0.9 mg/mL of methanol concentration at 30 °C for 96 h), a high yield of approximately 95 mg/L of CCMV CPs was harvested from the fermentation supernatant with CPs purity >90%, which has significantly simplified the rest of the purification process. The resultant CPs are employed to encapsulate Ruthenium (Ru) nanoparticles (NPs) via in-vitro self-assembly to prepare hybrid nanocatalyst, i.e. Ru@virus-like particles (VLPs). The catalytic activity over Ru@VLPs was evaluated by reducing 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The results indicate that, with the protection of protein cages, Ru NPs were highly stabilized during the catalytic reaction. This results in enhanced catalytic activity (reaction rate constant k = 0.14 min−1) in comparison with unsupported citrate-stabilized Ru NPs (Ru-CA) (k = 0.08 min−1). Additionally, comparatively lower activation energy over Ru@VLPs (approximately 32 kJ/mol) than that over Ru-CA (approximately 39 kJ/mol) could be attributed to the synergistic effect between Ru NPs and some functional groups such as amino groups (–NH2) on CPs that weakened the activation barrier of 4-NP reduction. Therefore, enhanced activity and decreased activation energy over Ru@VLPs demonstrated the superiority of Ru@VLPs to unsupported Ru-CA
What could the entire cornstover contribute to the enhancement of waste activated sludge acidification? Performance assessment and microbial community analysis
Microbial electrolysis contribution to anaerobic digestion of waste activated sludge, leading to accelerated methane production
Methane production rate (MPR) in waste activated sludge (WAS) digestion processes is typically limited by the initial steps of complex organic matter degradation, leading to a limited MPR due to sludge fermentation speed of solid particles. In this study, a novel microbial electrolysis AD reactor (ME-AD) was used to accelerate methane production for energy recovery from WAS. Carbon bioconversion was accelerated by ME producing H-2 at the cathode. MPR was enhanced to 91.8 gCH(4)/m(3) reactor/d in the microbial electrolysis ME-AD reactor, thus improving the rate by 3 times compared to control conditions (30.6 gCH(4)/m(3) reactor/d in AD). The methane production yield reached 116.2 mg/g VSS in the ME-AD reactor. According to balance calculation on electron transfer and methane yield, the increased methane production was mostly dependent on electron contribution through the ME system. Thus, the use of the novel ME-AD reactor allowed to significantly enhance carbon degradation and methane production from WAS. (C) 2016 Elsevier Ltd. All rights reserved
Compartmentalized Thin Films with Customized Functionality via Interfacial Cross-linking of Protein Cages
Hybrid thin films with a high loading and homogeneous dispersion of functional nanoparticles (and/or molecules) find applications in (bio)-sensors and electronic devices. The fabrication of such hybrid thin films, however, suffers from the complex and diverse surface and physicochemical properties of individual nanoparticles. To address this challenge, a facile and general strategy toward compartmentalized thin films through the interfacial cross-linking of viral protein cages is reported. Employing these protein cages, gold nanoparticles, as well as enzyme horseradish peroxidase, are encapsulated into virus-like particles and then cross-linked into thin films with a thickness varying from monolayer to submicron dimensions. These compartmentalized thin films not only ensure that the cargo is homogeneously dispersed, but also display good catalytic activity. This strategy is, in principle, applicable for a wide range of (bio)-organic nanocontainers, enabling the versatile fabrication of 2D thin films with extensive application prospects.</p
Compartmentalized supramolecular hydrogels based on viral nanocages towards sophisticated cargo administration
Introduction of compartments with defined spaces inside a hydrogel network brings unique features, such as cargo quantification, stabilization and diminishment of burst release, which are all desired for biomedical applications. As a proof of concept, guest-modified cowpea chlorotic mottle virus (CCMV) particles and complementary guest-modified hydroxylpropyl cellulose (HPC) were non-covalently cross-linked through the formation of ternary host-guest complexes with cucurbit[8]uril (CB[8]). Furthermore, CCMV based virus-like particles (VLPs) loaded with tetrasulfonated zinc phthalocyanine (ZnPc) were prepared, with a loading efficiency up to 99%, which are subsequently successfully integrated inside the supramolecular hydrogel network. It was shown that compartments provided by protein cages not only help to quantify the loaded ZnPc cargo, but also improve the water solubility of ZnPc to avoid undesired aggregation. Moreover, the VLPs together with ZnPc cargo can be released in a controlled way without an initial burst release. The photodynamic effect of ZnPc molecules was retained after encapsulation of capsid protein and release from the hydrogel. This line of research suggests a new approach for sophisticated drug administration in supramolecular hydrogels.</p
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Nanoscale Fluid Transport: Size and Rate Effects
The transport behavior of water molecules inside a model carbon nanotube is investigated by using nonequilibrium molecular dynamcis (NMED) simulations. The shearing stress between the nanotube wall and the water molecules is identified as a key factor in determining the nanofluidic properties. Due to the effect of nanoscale confinement, the effective shearing stress is not only size sensitive but also strongly dependent on the fluid flow rate. Consequently, the nominal viscosity of the confined water decreases rapidly as the tube radius is reduced or when a faster flow rate is maintained. An infiltration experiment on a nanoporous carbon is performed to qualitatively validate these findings
The growing inequality between firms
Globalisation, technological progress and a range of policies and institutions are driving ‘Great Divergences’ in wages and productivity, write Giuseppe Berlingieri, Patrick Blanchenay and Chiara Criscuol
Structure−Function Correlation of Chloroquine and Analogues as Transgene Expression Enhancers in Nonviral Gene Delivery
To understand how chloroquine (CQ) enhances transgene expression in polycation-based, nonviral gene delivery systems, a number of CQ analogues with variations in the aliphatic amino side chain or in the aromatic ring are synthesized and investigated. Our studies indicate that the aliphatic amino moiety of CQ is essential to provide increased gene expression. Further, the enhancements are more dramatically affected by changes to the aromatic ring and are positively correlated to the strength of intercalation between DNA and the CQ analogues. Quinacrine (QC), a CQ analogue with a fused acridinyl structure that can strongly intercalate DNA, enhances transfection similarly to CQ at a concentration 10 times lower, while N^4-(4-pyridinyl)-N^1,N^1-diethyl-1,4-pentanediamine (CP), a CQ analogue that has a weakly intercalating pyridinyl ring, shows no effect on gene expression. Subtle change on the 7-substituent of the chloroquine aromatic structure can also greatly affect the ability of the CQ analogues to enhance transgene expression. Transfection in the presence of N^4-(7-trifluoromethyl-4-quinolinyl)-N^1,N^1-diethyl-1,4-pentanediamin e (CQ7a) shows expression efficiency 10 times higher than in the presence of CQ at same concentration, while transfection in the presence of N^4-(4-quinolinyl)-N^1,N^1-diethyl-1,4-pentanediamine (CQ7b) does not reveal any enhancing effects on expression. Through a number of comparative studies with CQ and its analogues, we conclude that there are at least three mechanistic features of CQ that lead to the enhancement in gene expression: (i) pH buffering in endocytic vesicles, (ii) displacement of polycations from the nucleic acids in polyplexes, and (iii) alteration of the biophysical properties of the released nucleic acid
Prognostic significance of peripheral CD8+CD28+ and CD8+CD28- T cells in advanced non-small cell lung cancer patients treated with chemo(radio)therapy.
peer reviewed[en] BACKGROUND: Noninvasive prognostic biomarkers are needed for advanced non-small cell lung cancer (NSCLC) patients with different histological types to identify cases with poor survival. Here, we investigated the prognostic values of peripheral CD8+CD28+ T cells and CD8+CD28- T cells in advanced NSCLC patients treated with chemo(radio)therapy and the impact of histological type on them.
METHODS: Of 232 registered advanced NSCLC patients, 101 treatment-naïve individuals were eligible and included in our study. Flow cytometry was used to evaluate CD8+CD28+ T cells, CD8+CD28- T cells, CD4+ CD25hi T cells, B cells, natural killer cells, γδT cells, and natural killer T cells in patients' peripheral blood.
RESULTS: The median follow-up time was 13.6 months. Fifty-nine (58.4%) patients died by the end of our study. Fifty-three of the 101 advanced NSCLC cases selected for our study were adenocarcinomas (ADs), and 48 were squamous cell carcinomas (SCCs). Multivariate analyses showed that increased levels of CD8+CD28+ T cells independently predicted favorable overall survival (OS) [hazard ratio (HR): 0.51, 95% confidence interval (CI) 0.30-0.89, P = 0.021] and progression-free survival (PFS) (HR: 0.66, 95% CI 0.37-0.93, P = 0.038) in ADs, but the prediction in SCCs was not statistically significant. In contrast, high levels of CD8+CD28- T cells independently predicted unfavorable OS (HR: 1.41, 95% CI 1.17-3.06, P = 0.035) and PFS (HR: 2.01, 95% CI 1.06-3.85, P = 0.029) in SCCs, but the prediction in ADs was not statistically significant. ADs had higher levels of CD4+CD25hi T cells and CD8+CD28- T cells and lower NK cells (all P < 0.05) than SCCs.
CONCLUSIONS: Our findings uncovered the prognostic values of peripheral CD8+CD28+ T cells and CD8+CD28- T cells in advanced NSCLC patients treated with chemo(radio)therapy, which could help to identify patients with poor outcomes and refine treatment strategies
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