The NiOOH catalyst as obtained dynamically from electrodeposition of Ni2+(aq) in the borate-containing electrolyte was observed to exhibit much higher oxygen evolution activity at a near-neutral pH ...range (7–9) compared to other NiO x -based materials. Here, we demonstrate that this intriguing high activity is owing to the high concentration of Ni cationic vacancy on the nascent ultra-small NiOOH particles (<3 nm). By using first-principles calculations, we compute the thermodynamics of Ni dissolution and clarify the mechanism of oxygen evolution reaction (OER) on the γ-NiOOH surface. We show that (i) ∼4% Ni cations on the surface of γ-NiOOH dissolve at pH = 7 and 1.73 V versus reversible hydrogen electrode; (ii) on the pristine γ-NiOOH surface, OER proceeds via the “lattice peroxide” mechanism (*H2O → *OH → *O–OlattH* → O–Olatt → O2) with an overpotential of 0.70 V; (iii) in the presence of Ni cationic vacancies, OER proceeds via the “hydroperoxide” mechanism (*OH + *H2O → *2OH → *OOH → O2) with an overpotential of 0.40 V. Our electronic structure and geometrical structure analyses demonstrate that the structural flexibility at the four-coordinated Ni site nearby Ni vacancy, featuring the ability to bind two terminal oxo species, is key to boost the activity. Considering the presence of the active OOH intermediate, our theory thus implies that the ultra-small oxide nanoclusters with ample cation vacancies could be a paradigm in catalyst design for oxidation reactions.
The diverse biological effects of nanomaterials form the basis for their applications in biomedicine but also cause safety issues. Induction of autophagy is a cellular response after nanoparticles ...exposure. It may be beneficial in some circumstances, yet autophagy‐mediated toxicity raises an alarming concern. Previously, it has been reported that upconversion nanoparticles (UCNs) elicit liver damage, with autophagy contributing most of this toxicity. However, the detailed mechanism is unclear. This study reveals persistent presence of enlarged autolysosomes in hepatocytes after exposure to UCNs and SiO2 nanoparticles both in vitro and in vivo. This phenomenon is due to anomaly in the autophagy termination process named autophagic lysosome reformation (ALR). Phosphatidylinositol 4‐phosphate (PI(4)P) relocates onto autolysosome membrane, which is a key event of ALR. PI(4)P is then converted into phosphatidylinositol 4,5‐bisphosphate (PI(4,5)P2) by phosphatidylinositol‐4‐phosphate 5‐kinase. Clathrin is subsequently recruited by PI(4,5)P2 and leads to tubule budding of ALR. Yet it is observed that PI(4)P cannot be converted in nanoparticle‐treated hepatocytes cells. Exogenous supplement of PI(4,5)P2 suppresses the enlarged autolysosomes in vitro. Abolishment of these enlarged autolysosomes by autophagy inhibitor relieves the hepatotoxicity of UCNs in vivo. The results provide evidence for disrupted ALR in nanoparticle‐treated hepatocytes, suggesting that the termination of nanoparticle‐induced autophagy is of equal importance as the initiation.
In hepatocytes treated with upconversion nanoparticles (UCN) or nano‐SiO2, loss of phosphatidylinositol‐4‐phosphate 5‐kinase causes the disrupted phospholipid transition from phosphatidylinositol 4‐phosphate to phosphatidylinositol 4,5‐bisphosphate on enlarged autolysosomal membrane and clathrin fails to be recruited to autolysosomes; autophagic lysosome reformation is blocked, leading to enlarged autolysosomes. In the UCN‐treated mice liver, manipulation of autophagy by 3‐methyladenine or trehalose affects liver damage.
Polyamide (PA) thin-film composite (TFC) reverse osmosis (RO) membrane has been widely used for desalination to produce fresh water. In order to further enhance the membrane’s water flux without ...sacrificing the salt rejection, in this study, a new kind of three-dimension (3D) multi-layer graphene oxide (mGO) was synthesized through the layer-by-layer (LbL) crosslinking between the sing-layer GO (sGO) nanosheet and 1,3-diamino-2-propanol (DAPL) molecule, and then was introduced into the aqueous phase solution to modify the conventional polyamide TFC RO membrane via interfacial polymerization (IP). The size and structure of mGO were regulated through the optimization of LbL crosslinking techniques, and the effect of mGO on the micro-structure and macro-property of thin-film nanocomposite (TFN) RO membrane was correspondingly investigated. It was found that the mGO made the PA layer surface of RO membrane smoother and more hydrophilic. Most importantly, it increased the water flux of RO membrane, improved the salt rejection above 99.3%, and endowed the RO membrane better long-term stability. Obviously, this is due to that mGO created a certain d-spacing through crosslinking DAPL molecules between sGO nanosheets, which provided channels for water transport across the PA layer and thus accelerated the migration of water molecules in the membrane, ultimately enhancing the water flux of TFN RO membrane. Meanwhile, the DAPL grafted on the outmost surface of mGO enhanced the compatibility between mGO(30) and PA polymeric matrix via the reaction with TMC during the IP, further improving the membrane’s salt rejection. Therefore, this study provides a facile way to improve the comprehensive separation performance of RO membrane.
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•3D mGO was synthesized via LbL crosslinking between sGO nanosheet and DAPL.•The mGO was introduced in aqueous phase to modify the conventional TFC RO membrane.•The PA layer of mGO-based TFN RO membrane become thinner and more hydrophilic.•Flux and rejection of the mGO-based TFN RO membrane were improved concurrently.•Performance improvement is due to the channels in mGO and the DAPL grafted on mGO.
Integrated multi-omics evaluation of 823 tumors from advanced renal cell carcinoma (RCC) patients identifies molecular subsets associated with differential clinical outcomes to angiogenesis blockade ...alone or with a checkpoint inhibitor. Unsupervised transcriptomic analysis reveals seven molecular subsets with distinct angiogenesis, immune, cell-cycle, metabolism, and stromal programs. While sunitinib and atezolizumab + bevacizumab are effective in subsets with high angiogenesis, atezolizumab + bevacizumab improves clinical benefit in tumors with high T-effector and/or cell-cycle transcription. Somatic mutations in PBRM1 and KDM5C associate with high angiogenesis and AMPK/fatty acid oxidation gene expression, while CDKN2A/B and TP53 alterations associate with increased cell-cycle and anabolic metabolism. Sarcomatoid tumors exhibit lower prevalence of PBRM1 mutations and angiogenesis markers, frequent CDKN2A/B alterations, and increased PD-L1 expression. These findings can be applied to molecularly stratify patients, explain improved outcomes of sarcomatoid tumors to checkpoint blockade versus antiangiogenics alone, and develop personalized therapies in RCC and other indications.
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•Genomics of 823 RCC tumors, including 134 sarcomatoid tumors, reveals 7 subtypes•Subtype specific angiogenesis, immune, metabolic, stromal, and cell-cycle profiles•Differential prevalence of PBRM1, KDM5C, CDKN2A/2B, and TP53 alterations in subsets•Differential outcomes to VEGF blockade alone or in combination with anti-PD-L1
Motzer et al. perform integrative multi-omics analyses of 823 renal cancer tumors from a randomized clinical trial. A robust molecular classification scheme, based on transcriptional and gene alteration profiles and differential clinical outcomes to VEGF blockade alone or in combination with anti-PD-L1, informs personalized treatment strategies and future therapeutic development in RCC.
Land use and climate are two main factors directly influencing catchment hydrology, and separation of their effects is of great importance for land use planning and water resources management. Using ...the SWAT (Soil and Water Assessment Tools) model, we assessed the impacts of land use change and climate variability on surface hydrology (runoff, soil water and evapotranspiration) in an agricultural catchment on the Loess Plateau of China. Results indicated that SWAT proved to be a powerful tool to simulate the effect of environmental change on surface hydrology. The Nash–Sutcliffe model efficiency (Ens), Percent bias (PBIAS) and ratio of root mean square error to measured standard deviation (RSR) for annual flow was 0.87, 4.0%, 0.36 during calibration period and 0.87, 2.5%, 0.36 during validation periods, respectively. During 1981–2000, about 4.5% of the catchment area was changed mainly from shrubland and sparse woodland to medium and high grassland, and climate changed to warmer and drier. The integrated effects of the land use change and climate variability decreased runoff, soil water contents and evapotranspiration. Both land use change and climate variability decreased runoff by 9.6% and 95.8%, respectively, and decreased soil water contents by 18.8% and 77.1%. Land use change increased evapotranspiration by 8.0% while climate variability decreased it by 103.0%. The climate variability influenced the surface hydrology more significantly than the land use change in the Heihe catchment during 1981–2000; therefore, the influence of climate variability should be considered and assessed separately when quantifying the hydrological effect of vegetation restoration in the Loess Plateau.
In this work, we report a novel thin film composite (TFC) nanofiltration membrane (NFM) by incorporating a thin hydrophilic multi-walled carbon nanotubes (MWCNTs) interlayer between the ...microfiltration membrane support and the dense skin layer from interfacial polymerization. The MWCNT interlayer can absorb and storage the aqueous amino solution to facilitate the following interfacial polymerization, as well as provide a robust mechanical support to enable the nanofiltration of thin skin layer on the microporous substrate. Compared to those TFC NFMs supported by the ultrafiltration membranes, our membranes exhibit increased water permeation flux as high as 105.4 L m super(-2) h super(-1) at 0.6 MPa (which doubles the flux of the conventional ones) with high rejection for Na sub(2)SO sub(4) (~95%). Moreover, the TFC NFMs show good stability during a long-term nanofiltration operation. This research provides us a promising approach to fabricate the high-flux NFMs for low pressure operation.
Two new species of the genus Clubiona Latreille, 1804 are described: C. tianpingshan sp. nov. (♂♀) and C. flammaforma sp. nov. (♂♀) from central and south China. The female of C. subcylindrata Wang ...et al., 2018 is described for the first time. Detailed descriptions, photographs of somatic features and copulatory organs, as well as a distribution map of these three species, are provided.
Organic solvent ultrafiltration (OSU) membrane as the crucial supporting layer of thin-film composite (TFC) organic solvent nanofiltration (OSN) membrane can help the OSN technology to satisfy the ...rapidly growing demand for small-molecular separation and purification in organic solvent systems. Aiming at the two main bottlenecks of poor tolerance to strong polar solvents and low solvent flux of the conventional commercial polyimide (PI) ultrafiltration (UF) membrane, in this study, a facile method was proposed to prepare a novel polyimide/polyethyleneimine@TiO2 (PI/PEI@TiO2) OSU membrane with improved solvent resistance and permeability by synchronously coupling the non-solvent-induced phase transformation (NIPs), chemical crosslinking and interfacial in-situ biomineralization. Dut to the chemical crosslinking between PEI and PI, the PI/PEI@TiO2 membrane exhibited good resistance to more organic solvents including the strong polar aprotic solvents (e.g., DMF, NMP and DMSO), ordinary polar solvents (e.g., ethanol) and nonpolar solvents (e.g., n-hexane). At the same time, PEI synchronously catalyzed Ti-BALDH to in-situ generate the TiO2 nanoparticles via interfacial biomineralization, which improved the solvent flux of the PI/PEI@TiO2 membrane due to the creation of more channels and promoted the compatibility of TiO2 within PI/PEI matrix. Especially, the PI/PEI@TiO2-5 membrane with 5 wt% TiO2 loading showed the optimal solvent resistance and high flux in strong polar aprotic solvents (>50 L m−2 h−1·bar−1 in DMF). Therefore, the resultant new PI/PEI@TiO2 OSU membrane will have a promising separation application in the organic solvent systems in the future.
A novel organic solvent ultrafiltration membrane of polyimide/polyethyleneimine@TiO2 (PI/PEI@TiO2) was fabricated by synchronously coupling the non-solvent-induced phase transformation (NIPs), chemical crosslinking and interfacial in-situ biomineralization processes. The resultant PI/PEI@TiO2 UF membrane exhibited good resistance to more organic solvents including the strong polar aprotic solvents (e.g., DMF, NMP and DMSO), ordinary polar solvents (e.g., ethanol) and nonpolar solvents (e.g., n-hexane), and high flux of strong polar aprotic solvents without sacrificing the molecular weight cutoff. Display omitted
•A PI/PEI@TiO2 membrane was fabricated by coupling the NIPs, chemical crosslinking and interfacial biomineralization.•The PI/PEI@TiO2 membrane exhibited good resistance to more organic solvents including strong polar and non-polar solvents.•The PI/PEI@TiO2 membrane showed high flux of strong polar aprotic solvents as well as lower MWCO.•The PI/PEI@TiO2 membrane presented favorable long-term separation stability in strong polar aprotic solvent.
► The present spatiotemporal characteristics of ET
0 on the Loess Plateau were examined. ► ET
0 has increased significantly during 1961–2009. ► HadCM3 projects a continuous increase in ET
0 in the ...21st century. ► ET
0 will increase with a gradient from northeast to southwest in the 21st century.
The present and future spatiotemporal characteristics of reference evapotranspiration (ET
0) are examined in this paper. ET
0 during 1961–2009 are calculated by the Penman–Monteith method recommended by FAO (Food and Agriculture Organization) with historical weather data while ET
0 during 2011–2099 are downscaled from HadCM3 (Hadley Centre Coupled Model, version 3) outputs under two emission scenarios (A2 and B2) by SDSM (Statistical DownScaling Model). The spatial distribution and temporal trend in ET
0 are interpreted by Inverse Distance Weighted Interpolation and Mann–Kendall method, respectively. Results show that the annual mean ET
0 is 1060.3
mm, the lowest and highest values are found in the southwest and northwest region due to the spatial distribution of climatic factors, respectively. ET
0 has increased significantly due to the downward trend in relative humidity and upward trend in temperature on the Loess Plateau during 1961–2009. HadCM3 projects a continuous increase in ET
0 in the 21st century and the upward trend will be more pronounced after 2050. Averaged over the two emission scenarios for the whole area, the projected increase are 4%, 7% and 12% for the three periods 2011–2040, 2041–2070 and 2071–2099, respectively; the increase under A2 scenario are slightly greater than those under B2 scenario. An obvious gradient is detected for the projected increase in ET
0 from northeast to southwest region in the 21st century. The increase in ET
0 will possibly influence the water resource on the Loess in the 21st century and some countermeasures should be taken to reduce the adverse impacts.
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