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Comprehensive treatment of multifarious contaminations in waterbody demands multifunctional adsorbents with easy reusability, high efficiency, and broad-spectrum adsorption performance. Herein hydrothermally reduced graphene oxide/poly (vinyl alcohol) (TRGO/PVA) aerogels fulfilling these requirements were developed via a facile and green in situ hydrothermal reduction followed by direct sol-aerogel transformation strategy. The interfacial interaction between TRGO sheets and PVA macromolecules as proved by various methods could effectively prevent TRGO from aggregation, which improves mechanical and adsorption performances and assures reusability of aerogels. The aerogels demonstrate an attractive broad-spectrum universality in adsorbing diverse cationic, anionic and nonionic dyes, surpassing most adsorbents that could only remove either positively or negatively charged dyes. The aerogels demonstrate a promising synergetic effect for adsorption two oppositely charged dyes, exhibiting the highest total adsorption amount (>900 mg/g) among known absorbents for removing mixed dyes. Besides, the aerogels after hydrophobic modification are able to effectively adsorb common oils and organic solvents spilling on water. Furthermore, the aerogels are compressible, dimension stable and solvent resistive and can be easily regenerated, bringing a great superiority in the comprehensive treatment of multiple contaminations in waterbody. [ABSTRACT FROM AUTHOR]

Sustainable development of mountain areas and resource cities has been a significant issue worldwide. Transformation of mountain resource cities is facing tremendous difficulties. In the context of National Major Function-oriented Zone Planning raised to a national strategic level in China, it is important to effectively implement the planning by studying geographical space development zone classification of prefecture- and county-level cities based on their major function orientation. This research is even more critical for the transformation of mountain resource cities. In this study, we evaluated geographical space development suitability, and classified geographical space development zones for Dongchuan Distric in Kunming City of Yunan Province, China, a typical mountain resource city. A quantitative grid-based evaluation was conducted using key-factor identification and restrictive-supportive comprehensive index determinati based on a geographic information system framework with different source data. The results included a classification of geographical space of Dongchuan into five types: the prohibited development zone, the inappropriate development zone, the controlled development zone, the moderate development zone and the preferential development zone. The distribution characteristics of geographical space development zones showed that the proportion of the prohibited development zone is the highest, while that of the other four development zones is comparatively lower and significantly fragmented. The geographical space development suitability is greatly controlled by the geomorphic pattern. Although Dongchuan is extremely restrained in terms of suitable geographical space for industrialization and urbanization, it still has the certain preferential and moderate development zones with an area of 207.81 km with large parts being concentrated and contiguous, which makes these areas the most favorable for development. Only by adapting to this reality and implementing centralized development strategy in the regions with higher suitability may Dongchuan achieve smooth transformation from expansion mode to compact mode and its sustainable development capacity may be improved. Suggestions with an angle of industrial and spatial development pattern were put forward for the transformation of the city in future. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis is a heterogeneous disease with clinical and biological polymorphisms. IL-1RN is a protein that binds to interleukin-1 (IL-1) receptors and inhibits the binding of IL-1-alpha and IL-1-beta. IL-1RN levels are elevated in the blood of patients with a variety of infectious, immune, and traumatic conditions. Balb/c mice deficient in IL-1ra (mouse gene of IL-1RN) develop spontaneous autoimmune arthritis while DBA/1 mice deficient in IL-1ra do not. Previously, we identified a major QTL that regulates the susceptibility to arthritis in Balb/c mice with IL-1ra deficiency. In this study, we found that the QTL may contain two peaks that are regulated by two sets of candidate genes. By haplotype analysis, the total genomic regions of candidate genes were reduced from about 19 Mbp to approximately 9 Mbp. The total number of candidate genes was reduced from 208 to 21. [ABSTRACT FROM AUTHOR]

Abstract: Microgravity has a unique effect on biological organisms. Organs exposed to microgravity display cellular senescence, a change that resembles the aging process. To directly investigate the influence of simulated microgravity on neuronal original rat PC12 cells, we used a rotary cell culture system that simulates the microgravity environment on the earth. We found that simulated microgravity induced partial G1 phase arrest, upregulated senescence-associated β-galactosidase (SA-β-gal) activity, and activated both p53 and p16 protein pathways linked to cell senescence. The amount of reactive oxygen species (ROS) was also increased. The activity of intracellular antioxidant enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), was all significantly increased at 12h after the microgravity onset, yet decreased at 96h. Furthermore, concomitant block of ROS by the antioxidant N-acetylcysteine significantly inhibited the microgravity-induced upregulation of SA-β-gal activity. These results suggest that exposure to simulated microgravity induces cellular senescence in PC12 cells via an increased oxidant stress. [Copyright &y& Elsevier]

This study proposed a novel strategy to fabricate highly permeable and robust supported membranes for membrane distillation, via a nonsolvent thermally induced phase separation method. Different from traditional supported membranes cast on non-woven fabrics, a well-integrated fabric-embedded PVDF (FE-PVDF) membrane was successfully obtained using polyamide 66 gauze supports. The optimal FE-PVDF membrane PA-120 exhibited an interesting structure with pseudo Janus function, which entailed hydrophobic bulk membrane property but a pseudo hydrophilic bottom surface due to the presence of water-filled "50 μm grade" pores. The PA-120 exhibited a DCMD flux of 68.5 kg.m−2.h−1 at 70 °C with synthetic saline solution and exceptional tensile strength of 21 MPa (lateral)/21 MPa (longitudinal), which was 1.4-fold and 23-fold higher than that of the unsupported benchmark, respectively. The concentration of 10 wt% monosodium glutamate solution with PA-120 was demonstrated at 70 °C up to 55 wt% when crystallization was observed, The flux showed a minor decrease by 16.3% until 40 wt% and a subsequent decline towards 55 wt%. Repeated concentration cycles were conducted with intermediate membrane rinsing by fresh feed, demonstrating highly recoverable performance. This preliminary study brings new perspectives towards pushing the limits of current lab-made MD membranes. [Display omitted] • Ultra-robust fabric-embedded PVDF membranes were obtained by a facile NTIPS method. • FE-PVDF membrane offered tensile strength 21 MPa and DCMD flux 68.5 kg.m−2.h−1 (70 °C). • Membrane structure with a pseudo Janus function led to greatly enhanced mass transfer. • Successful concentration of MSG solution was conducted towards crystallization. • Reversible MD performance demonstrated in repeated cycles with no additional cleaning. [ABSTRACT FROM AUTHOR]

• Viability of Cryptosporidium oocysts is a risk factor for the waterborne pathogen. • Oocyst viability also measures deactivation efficiency in water treatments. • Inviable oocysts in water may retain structure and DNA for weeks to months. • Commonly used microscopic/PCR methods cannot measure or quantify oocyst viability. • New assays are developed and validated to quantify viable oocysts that infect humans. While waters might be contaminated by oocysts from >40 Cryptosporidium species, only viable oocysts of C. parvum and C. hominis truly pose the main health risk to the immunocompetent population. Oocyst viability is also an important but often neglected risk factor in monitoring waterborne parasites. However, commonly used methods in water monitoring and surveys cannot distinguish species (microscopic observation) or oocyst viability (PCR), as dead oocysts in water could retain gross structure and DNA content for weeks to months. Here, we report new TaqMan qRT-PCR/qPCR assays for quantitative detection of viable C. parvum and C. hominis oocysts. By targeting a hypothetical protein-encoding gene cgd6_3920 that is highly expressed in oocysts and variable between species, the qRT-PCR/qPCR assays achieve excellent analytical specificity and sensitivity (limit of quantification [LOQ] = 0.25 and 1.0 oocyst/reaction). Using calibration curves, the number and ratio of viable oocysts in specimens could be calculated. Additionally, we also establish a TaqMan-18S qPCR for cost-effective screening of pan- Cryptosporidium -positive specimens (LOQ = 0.1 oocyst/reaction). The assay feasibility is validated using field water (N = 43) and soil (79) specimens from 17 locations in Changchun, China, which detects four Cryptosporidium species from seven locations, including three gp60 -subtypes (i.e., IIdA19G1, IIdA17G1 and IIdA24G2) of C. parvum oocysts showing varied viability ratios. These new TaqMan q(RT)-PCR assays supplement current methods in the survey of waters and other samples (e.g., surfaces, foods and beverages), and are applicable to assessing the efficiency of oocyst deactivation protocols. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Nano-pore size is the key factor to determine the performance of porous membrane in various applications. The programmable and continuous manipulation of it remains as a great challenge. In this work, nano-porous shape memory polymer (SMP) membrane has been fabricated successfully in ternary blend of PVDF, PBSU and random copolymer (BMG) based on the special interface interaction and complicated phase behaviors among them. On one hand, phase separation takes place, producing bicontinuous structures with the characteristic size of microns including BMG rich phase and PVDF/PBSU mixed phase. The former provides shape memory effect in which cross-linked points and network play the roles of shape fixed phase and recovery phase respectively; on the other hand, exclusion of PBSU during crystallization of PVDF contributes to bicontinuous structures in nanoscale. The removal of PBSU based on double bicontinuous structures results in the interconnected nano-pores. The obtained nano-porous PVDF/BMG composite membranes possess not only shape memory performance, but also the interpenetrated channels. The pore size has been manipulated successfully by means of biaxial tension based on the proportional deformation in macro- and micro-scales. Our results provide a new strategy for the fabrication of nano-porous SMPs and the manipulation of pore size in them. Highlights • Double bicontinuous structures have been obtained based on the complicated phase behaviors in ternary blend. • Nano-porous shape memory membranes were prepared successfully. • Pore-size in microscale has been tailored programmably by macroscopic deformation. [ABSTRACT FROM AUTHOR]

This study proposes using membrane distillation (MD) as an alternative to the conventional multi-stage flushing (MSF) process to concentrate a semi-product of organic fertilizer. By applying a unique asymmetric polyvinylidene fluoride (PVDF) membrane, which was specifically designed for MD applications using a nonsolvent thermally induced phase separation (NTIPS) method, the direct contact membrane distillation (DCMD) performance was investigated in terms of its sustainability in permeation flux, fouling resistance, and anti-wetting properties. It was found that the permeation flux increased with increasing flow rate, while the top-surface facing feed mode was the preferred orientation to achieve 25% higher flux than the bottom-surface facing feed mode. Compared to the commercial polytetrafluoroethylene (PTFE) membrane, the asymmetric PVDF membrane exhibited excellent anti-fouling and sustainable flux, with less than 8% flux decline in a 15 h continuous operation, i.e., flux decreased slightly and was maintained as high as 74 kg·m-2·h-1 at 70 °C. Meanwhile, the lost flux was easily recovered by clean water rinsing. Overall 2.6 times concentration factor was achieved in 15 h MD operation, with 63.4% water being removed from the fertilizer sample. Further concentration could be achieved to reach the desired industrial standard of 5x concentration factor. [ABSTRACT FROM AUTHOR]

ABSTRACT The influence of nanosilica on the concentration fluctuation of polystyrene/poly (vinyl methyl ether) (PS/PVME) mixtures was investigated during phase separation. The amplitude of concentration fluctuation was quantified by dielectric spectrums based on the idea of Lodge-Mcleish model and the linearized Cahn-Hilliard theory could describe the amplitude evolution of concentration fluctuation at the early stage of phase separation. Hydrophilic nanosilica A200 dispersed in PVME-rich phase behaved an obvious inhibition effect on the concentration fluctuation of blend matrix, while hydrophobic nanosilica R974 dispersed in PS-rich phase had little effect on the concentration fluctuation. The kinetics and amplitude evolution of concentration fluctuation during phase separation for PS/PVME/A200 nanocomposites were remarkably restrained due to the surface adsorption of PVME on A200. As the segmental dynamics of PVME and PS in homogeneous matrix was hardly influenced by A200 and R974, the enhanced miscibility and the significantly constrained flow relaxation of PVME chains might contribute to the retarded concentration fluctuation of PS/PVME/A200 nanocomposites. While the weak interaction between R974 and components of blend matrix and little effect of R974 on the molecular dynamics of PS chains may result in the weak retardation of concentration fluctuation for blend matrix. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1337-1349 [ABSTRACT FROM AUTHOR]

We have examined the effects of bFGF (basic fibroblast growth factor) on p-ERK (phosphorylated extracellular signal-regulated kinase) through PDGFRβ (platelet-derived growth factor receptor β) in the proliferation and migration of EPCs (endothelial progenitor cells). EPC migration was detected using the Transwell system. The expression of PDGFRβ mRNA and protein, total ERK and p-ERK proteins was respectively assessed by real-time PCR and Western blottings. bFGF promote the proliferation and migration of EPCs, the effects of bFGF being implemented by activating ERK signalling through the expression of PDGFRβ, whereas an anti-bFGF antibody and inhibitor of PDGF (platelet-derived growth factor) receptor kinase (AG1296) could respectively decrease the expression of PDGFRβ mRNA and protein and p-ERK protein. Total ERK protein did not change under the same experimental conditions, and an inhibitor of p-ERK (PD98059) inhibited the proliferation and migration of EPCs. The findings strongly suggest that a PDGFRβ/p-ERK signalling pathway triggered by bFGF plays an important role in the proliferation and migration of EPCs. [ABSTRACT FROM AUTHOR]

Abstract: The use of helicopters as platforms equipped with infrared and UV detection, digital cameras and other inspection equipment is an effective method of increasing the efficiency and effectiveness of transmission line inspection. However, as a ''floating-potential conductor'' near to a high-voltage transmission line, a helicopter causes distortion of the local electric field, with regions of high electric field near the helicopter''s surface where the curvature is high. In this paper, these fields are investigated both by calculation and experimentally, using a simple metal sphere, and then a model of a helicopter, placed near to a short length of energized transmission line conductor. [Copyright &y& Elsevier]