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The degradation of toluene in dielectric barrier discharge (DBD) reactor packed with zeolites or MnOx/zeolites was investigated. The supported catalysts were prepared by loading 3 wt% of manganese on different zeolites (MCM-41, ZSM-5 and 13X) and were characterized in detail using N2 adsorption, XRD, TEM, H2-TPR and XPS analysis technology. Compared to the non-thermal plasma (NTP) alone system, the toluene degradation was improved significantly in NTP-MnOx/zeolites system. The highest toluene conversion of 99.4%, the CO2 selectivity of 73%, the carbon balance of 99.5% can be achieved in DBD reactor packed with MnOx/MCM-41. Both XRD and TEM results confirm that the manganese oxides were dispersed more uniformly on MnOx/MCM-41 than on MnOx/ZSM-5 or MnOx/13X. H2-TPR and XPS results suggest that manganese oxides on MnOx/MCM-41 are MnO2 and Mn2O3, while those on MnOx/ZSM-5 or MnOx/13X are MnO2 and MnO. These results indicate that the structures of zeolites play a significant role in the dispersion and oxidation state of manganese oxides, then affecting the activity of catalyst for toluene removal in plasma-catalysis system.

The present work investigated the effects of annealing on corrosion behavior, Ni2+ release, cytocompatibility, and antibacterial ability of nickel-titanium-oxygen (Ni-Ti-O) nanopores (NPs) anodically grown on nearly equiatomic NiTi alloy, aiming at optimizing annealing process to yield favorable comprehensive performance. The morphology and crystal structure of the NPs were characterized by scanning electron microscopy and X-ray diffraction respectively. It was found that when the annealing temperature was

Magnesium alloys have been recognized as promising implant materials because of their biodegradability. However, rapid degradation due to electrochemical corrosion compromises their cytocompatibility and mechanical integrity. In the present work, a porous ZrO2 ceramic coating was constructed on the surface of AZ31B magnesium alloy (ZrO2-AZ31B) to improve its corrosion resistance. The corrosion resistance of the coating was evaluated in simulated body fluid solution by electrochemical techniques. Higher open circuit potential, impedance and polarization resistance of ZrO2-AZ31B indicate it has a better corrosion resistance than that of AZ31B substrate in simulated body fluid solution. The results suggest that fabricating a ZrO2 ceramic coating on magnesium alloys is an effective method to decrease the degradation rate of magnesium alloys thereby better matching clinical requirements.

A regional air quality model system (RAQMS) was developed by coupling the treatment of heterogeneous reactions between sea salt aerosols (SSAs) and trace gases and applied to the investigation of aerosol properties and evolutionary features in the western Pacific Ocean in the spring of 2014. Model results for meteorological variables, PM concentrations, and size-resolved water soluble inorganic aerosol (WSIA) concentrations were compared and analyzed with a variety of observations from in situ measurements and the research cruise Dongfanghong II. Model validation demonstrated that the model can simulate the spatial-temporal distribution and size distribution of aerosol inorganic components in the marine atmosphere over East Asia, and the inclusion of heterogeneous reactions on SSAs apparently improved the model simulation for WSIA concentration, especially for aerosol size distribution. In the western Pacific Ocean, the non-sea salt SO42− and NO3− formed on SSAs accounted for up to 30% and 90% of surface SO42− and NO3− concentrations on average, respectively. The atmospheric depositions of total inorganic sulfur and nitrogen were estimated to be 13184 × 103 kgS/d and 10728 × 103 kgN/d, respectively. Wet deposition was the dominant removal pathway, which accounted for 75% and 68% of sulfur and nitrogen depositions, respectively. The deposition of fine-mode SO42− exceeded that of coarse-mode SO42−, whereas the deposition of coarse-mode NO3− was comparable to that of fine-mode NO3−. The non-sea salt SO42− and NO3− formed on SSAs contributed 16% and 9% of total sulfur and nitrogen depositions on average, respectively. The above results revealed the important role of SSAs in both atmospheric chemistry and deposition in the western Pacific Ocean.

In this study, we determined the concentrations of water-extracted dimethylaminium (DMA+) and trimethylaminium (TMA+) in size-segregated atmospheric particles collected during three inland campaigns and one sea-beach campaign in Qingdao and five marine campaigns in marginal seas of China and the northwest Pacific Ocean. The averages of DMA+ and TMA+ in PM0.056–10 (the sum of concentrations from 0.056 to 10 μm) during each campaign ranged from 0.045 to 1.1 nmol m−3 and from 0.029 to 0.53 nmol m−3, respectively. The increased concentrations of DMA+ and TMA+ in PM0.056–10, particularly the 1–2 orders of magnitude increased ratios of DMA+/NH4+ and TMA+/NH4+, in the marine and sea-beach atmospheres indicated that the overwhelming majority was derived from marine sources. Size distributions of TMA+ and DMA+ were also investigated in terms of phase states and formation pathways, e.g., the dominant modes of particulate DMA+ and TMA+ in some samples were characterized by the mass median aerodynamic diameter at 0.1–0.2 μm against the dominant mode of NH4+ and SO42− at 0.7–0.9 μm, while the ratios of DMA+/NH4+ and/or TMA+/NH4+ in 0.2 μm particles. This strongly implied that the particulate DMA+ and TMA+ at 0.2 μm size range mainly existed in the aqueous (or solid) phase where the dominance of gas-aerosol equilibria would cause the ratios to be almost size-independent. The size-dependent phase states corresponded to their various formation pathways.

Prevention of bacterial infection and promotion of osseointegration are two important issues for titanium (Ti) implants in medical research. In addition, after a biofilm is formed on the surface of implants, the immune system and antibiotic therapy may fail. In this work, bio-functionalized titanium dioxide (TiO

In this study, the seasonal mean PM

The influence of electrolyte pH on anodic growth of Ni-Ti-O nanopores on NiTi alloy was investigated. Through manipulating HCl, NaCl, and NaOH concentrations in the electrolyte composed of 95 vol% ethylene glycol, 5 vol% H2O, and 0.15 M Cl−, the electrolyte pH was varied from 0.82 to 13.5. Although the pH has little influence on surface morphology and composition of the nanopores, it can significantly impact their growth rate. Initially, increase of the pH decreases the growth rate from 13.8 nm/s at pH = 0.82 to 5.7 nm/s at pH = 7.0. However, when the pH exceeds 7.0, its value increases with the pH and reaches up to 15.8 nm/s at pH = 13.5. The knowledge gained from this study should be valuable in the anodization of other valve metals and their alloys.

Fabrication of SiC nanoarrays is highly recommended owing to the fact that it is the key to push forward them being applied in optoelectronic devices. Nevertheless, majority of the reported works involving the growth of SiC low-dimensional nanostructures were often carried out under the harsh conditions (e.g., high temperatures and/or high pressures), which were teemed as the key obstacle for the accomplishment of their controllable and repeatable growth. In the current work, we reported the controllable and repeatable large-scale fabrication (up to centimeter×centimeter of width × length in area) of well-aligned, free-standing and transparent 4H-SiC nanohole arrays via anodic oxidation of SiC wafers at room temperature and atmospheric pressure conditions. It was discovered that the cycle period of the pulsed voltage played a crucial role in the formation of highly uniform nanohole arrays. In the meantime, the diameters, wall thickness and depth of the nanoholes could be modulated through the customization of the cycle times. Additionally, a possible mechanism was proposed for the formation of nanohole arrays.

A multifaceted coating for hard tissue implants, with favorable osteogenesis, angiogenesis , and osteoimmunomodulation abilities, would be of great value since it could improve osseointegration and alleviate prosthesis loosening. However, to date there are few coatings that fully satisfy these criteria. Herein we describe a microporous TiO 2 coating decorated with hydroxyapatite (HA) nanoparticles that is generated by micro-arc oxidation of pure titanium (Ti) and followed annealing. By altering the annealing temperature, it is possible to simultaneously tune the coating's physical (morphology and wettability) and chemical (composites and crystallinity) properties. A coating produced with micro-arc oxidization (MAO) with an annealing temperature of 650 °C (MAO-650) exhibits numerous favorable physicochemical properties , such as hybrid micro-nano morphology, superhydrophilicity, and highly crystalline HA nanoparticles. In vitro experiments reveal that the MAO-650 coating not only supports proliferation and differentiation of both osteoblasts and endothelial cells, but also inhibits the inflammatory response of macrophages and enables a favorable osteoimmunomodulation to facilitate osteo/angio-genesis. In vivo evaluation mirrors these results, and shows that the MAO-650 coating results in ameliorative osseointegration when compared with the pristine MAO coating. These data highlight the profound effect of surface physicochemical properties on the regulation of osteo/angio-genesis and osteoimmunomodulation in the enhancement of osseointegration.

Percutaneous coronary intervention with stenting is the most widely adopted surgical technique for the treatment of coronary disease. However, in-stent restenosis (ISR) continues to cause serious concern. Improving the functionality of endothelial cells (ECs) is of importance for dealing with ISR. However, limited successes in in vivo studies imply that the underlying mechanism relating to the process of intervention with a material has not been well understood to date. Another determining factor that has long been underestimated in the design of stents is immune response dominated by macrophages (MΦs). In the present study, TiO2 nanotube arrays (TNAs) with different diameters were fabricated by anodization. The diameter could be precisely adjusted from 15 nm (Nano-15) to 120 nm (Nano-120). The effect of distinct nanodimensions on the behavior of ECs/MΦs and their crosstalk was investigated. The results indicated that Nano-15 not only promoted the initial vitality of ECs and function-related gene expression but also enhanced the activation and spread of MΦs. In addition, Nano-15 downregulated the gene expression of inflammatory cytokines and pro-inflammatory M1 markers, while upregulating the gene expression of pro-healing M2 markers, autophagy markers, and growth factors of MΦs. A further investigation conducted using a specialized specimen-conditioned medium (SCM) from MΦs/ECs disclosed that the SCM derived from Nano-15 was able to manipulate a favorable microenvironment to facilitate MΦ-EC crosstalk via downregulation of inflammation-related gene expression and upregulation of function-related gene expression in ECs. Moreover, we further investigated the hemocompatibility of specimens in an ex vivo animal model. The results indicated that both pure Ti and Nano-15 possess satisfactory hemocompatibility, as manifested by the few thrombi that formed around the specimens. Additionally, in comparison with Nano-120, Nano-15 can significantly alleviate platelet activation and manipulate a loose structure of fibrin fibers in a dynamic situation. This study suggests that the application of Nano-15 as a surface coating for coronary stents may be a promising strategy for preventing ISR.

Asian dust has been reported to carry anthropogenic reactive nitrogen during transport from source areas to the oceans. In this study, we attempted to characterize NH4+ and NO3− in atmospheric particles collected at a coastal site in northern China during spring dust events from 2008 to 2011. Based on the mass concentrations of NH4+ and NO3− in each total suspended particle (TSP) sample, the samples can be classified into increasing or decreasing types. In Category 1, the concentrations of NH4+ and NO3− were 20–440 % higher in dust day samples relative to samples collected immediately before or after a dust event. These concentrations decreased by 10–75 % in the dust day samples in Categories 2 and 3. Back trajectory analysis suggested that multiple factors, such as the transport distance prior to the reception site, the mixing layer depth on the transport route and the residence time across highly polluted regions, might affect the concentrations of NH4+ and NO3−. NH4+ in the dust day samples was likely either in the form of ammonium salts existing separately to dust aerosols or as the residual of incomplete reactions between ammonium salts and carbonate salts. NO3− in the dust day samples was attributed to various formation processes during the long-range transport. The positive matrix factorization (PMF) receptor model results showed that the contribution of soil dust increased from 23 to 36 % on dust days, with decreasing contributions from local anthropogenic inputs and associated secondary aerosols. The estimated deposition flux of NNH4++NO3− varied greatly from event to event; e.g., the dry deposition flux of NNH4++NO3− increased by 9–285 % in Category 1 but decreased by 46–73 % in Category 2. In Category 3, the average dry deposition fluxes of particulate nitrate and ammonium decreased by 46 % and increased by 10 %, respectively, leading to 11–48 % decrease in the fluxes of NNH4++NO3−.

The Yellow Sea Cold Water Mass (YSCWM), which occurs during summer in the central Yellow Sea, plays an important role in the hydrodynamic field, nutrient cycle and biological species. Based on water temperature observations during the summer from 1978 to 1998 in the western Yellow Sea, five specific YSCWM years were identified, including two strong years (1984 and 1985), two weak years (1989 and 1995) and one normal year (1992). Using a three-dimensional hydrodynamic model, the YSCWM formation processes in these five years were simulated and compared with observations. In general, the YSCWM began forming in spring, matured in summer and gradually disappeared in autumn of every year. The 8 °C isotherm was used to indicate the YSCWM boundary. The modelled YSCWM areas in the two strong years were approximately two times larger than those in the two weak years. Based on the simulations in the weak year of 1995, ten numerical experiments were performed to quantify the key factors influencing the YSCWM intensity by changing the initial water condition in the previous autumn, air-sea heat flux, wind, evaporation, precipitation and sea level pressure to those in the strong year of 1984, respectively. The results showed that the air-sea heat flux was the dominant factor influencing the YSCWM intensity, which contributed about 80% of the differences of the YSCWM average water temperature at a depth of 50 m. In addition, the air-sea heat flux in the previous winter had a determining effect, contributing more than 50% of the differences between the strong and weak YSCWM years. Finally, a simple formula for predicting the YSCWM intensity was established by using the key influencing factors, i.e., the sea surface temperature before the cooling season and the air-sea heat flux during the cooling season from the previous December to the current February. With this formula, instead of a complicated numerical model, we were able to roughly predict the YSCWM intensity for the following summer by using the data available online in winter.

It has been reported that air quality models largely underestimate PM2.5 concentrations during severe pollution events in China. In this study, the Models-3 Community Multi-scale Air Quality model (CMAQ) was employed to simulate PM2.5 concentrations in May-June (non-heating period) and in November-December (heating period) of 2013 in northern China, with a particular focus on determining the causes of the underestimation. Modeling results reproduced the mass concentrations of PM2.5 in approximately 50% of the non-heating and heating periods in Qingdao (referred to as the good periods), while the model performance was unsatisfactory during the remaining periods (the poor periods). In this respect, the overprediction of inorganic salts and the underprediction of organic matter in PM2.5 canceled each other out and resulted in a good simulation of PM2.5 concentrations during the good periods, whereas during poor periods, the bias of the planetary boundary layer height, wind direction, precipitation, and other factors caused inconsistencies between the simulated and observed PM2.5 concentrations. Sensitivity studies showed that the underestimation of primarily emitted particles from local emissions was likely the main cause of PM2.5 underpredictions during heavy haze days. Furthermore, our results implied that the assumption of the conditions of the gas-aerosol thermodynamic equilibria in the air quality model likely results in an overprediction of secondary PM2.5 inorganic salts (SO42- + NO3- + NH4+) during clear days. In contrast, during heavy pollution or heavy haze days, high concentrations of air pollutants theoretically rapidly leads to gas/particle chemical equilibrium and no overprediction of SO42-, NO3-, and NH4+ concentrations. Nevertheless, the underestimation of primarily emitted particles from local sources during heavy haze days is yet to be explained and needs further investigation.

Osseointegration is a sophisticated bone and implant healing process comprising of initial hematoma formation, immediate osteoimmunomodulation, angiogenesis, and osteogenesis. To fulfill rapid and satisfying osseointegration, this study developed a biomimetic implant coating that could confer the intraosseous implants a systematical regulation of the participatory processes. Herein, we shaped dissimilar nano-scale (NS) to form highly biomimetic structures of natural extracellular matrix (ECM) of the host bone and bone healing hematoma with micro/nano-scale (MNS) titania fiber-like network on the surface of titanium (Ti) implants. In vitro experiments revealed that the MNS not only facilitated osteogenic and angiogenic differentiation of bone marrow stromal cells (BMSCs) and endothelial cells, respectively, but also suppressed M1 macrophages (MΦs), whereas, stimulated pro-healing M2 phenotype. Notably, BMSCs on MNS surfaces enabled a significant immunomodulatory effect on MΦs resulting in the downregulation of inflammation-related cell signaling pathways. The favorable osteoimmune microenvironment manipulated by MNS further facilitated osteo-/angio-genesis via the crosstalk of multi-signaling pathways. In vivo evaluation mirrored the aforementioned results, and depicted that MNS induced ameliorative osseointegration when compared with the NS as well as the pristine Ti implant. The study demonstrated the modulatory effect of the multifaceted biomimetic structure on spatiotemporal regulation of the participatory processes during osseointegration.

The whole complete chloroplast (cp) genome sequence of Actinidia kolomikta (formerly A. maloide) was sequenced and assembled from Illumina paired-end sequencing. The cp genome of A. arguta was 157,425 bp long, containing a large single copy region (LSC) of 88,498 bp and a small single copy region (SSC) of 20,475 bp and a pair of inverted repeat regions (IR) of 242,266 bp. It contained 113 different genes, including 79 protein-coding genes, 30 tRNA genes, 4 ribosomal RNA genes. Phylogenetic analysis using concatenated alignments of whole cp genome sequences revealed that A. kolomikta was the sister group to all other groups of Actinidia

In this study, we present and validate a methodology for satellite retrievals of cloud condensation nuclei (CCN) in shallow marine boundary layer clouds. In our approach, supersaturation (S) is calculated by the retrieved cloud base drop concentration (Nd) and updrafts (Wb). Nd is the activated CCN concentration in clouds at a given S. We validate the accuracy of the satellite retrieval against surface-measured CCNs from a cruise campaign over the heavily polluted northwest Pacific Ocean. The satellite retrievals show a good agreement with surface measurements after performing corrections for temperature and adiabatic fraction when clouds are coupled with sea surface. This study broadens the applicability of the methodology from aerosol-limited to contaminated regions. The validation shows ±30% accuracy in retrieving CCN over both clean and polluted regions. The results further demonstrate the strong dependence of marine shallow cloud Nd on CCN number concentrations and updraft, which allows us to further apply this methodology to quantify CCN, cloud microphysical properties and the relationships between them. This is helpful in reducing the uncertainty of radiation forcing caused by the aerosol-cloud-interactions (ACI).

We report on a reliable and cost-effective method (alkali corrosion) to construct nanosheet layers on nearly equiatomic nickel-titanium (NiTi) alloy, which only needs to immerse it in1−15 M NaOH solution at low temperature (4–80 ℃). The layers are mainly composed of TiO2, Na4TiO4, and Ni(OH)2, and Ni content increases with NaOH concentration. The layers exhibit potent antibacterial ability and can promote endothelial spreading and proliferation, although the corrosion resistance is slightly decreased due to significantly increased specific surface area. Good corrosion resistance, antibacterial ability, and cytocompatibility render the nanosheet layers promising as biomedical coatings of the NiTi alloy.

With the rapid expansion of maritime traffic, increases in air emissions from shipping have exacerbated numerous environmental issues, including air pollution and climate change. However, the effects of such emissions on marine biogeochemistry remain poorly understood. Here, we collected ship-emitted particles (SEPs) from the stack of a heavy-oil-powered vessel using an onboard emission test system and investigated the impact of SEPs on phytoplankton growth over the northwest Pacific Ocean (NWPO). In SEP microcosm experiments conducted in oceanic zones with different trophic statuses, the phytoplankton response, as indicated by chlorophyll a (Chl a), has been shown to increase with the proportion of SEP-derived nitrogen (N) relative to N stocks (PSN) in baseline seawater, suggesting that SEPs generally promote phytoplankton growth via N fertilisation. Simulations using an air quality model combined with a ship emission inventory further showed that oxidised N (NOx) emissions from shipping contributed ~43% of the atmospheric N deposition flux in the NWPO. Air emissions from shipping (e.g. NOx and sulphur dioxide) also indirectly enhanced the deposition of reduced N that existed in the atmosphere, constituting ~15% of the atmospheric N deposition flux. These results suggest that the impact of airborne ship emissions on atmospheric N deposition is comparable to that of land-based emissions in the NWPO. Based on the ship-induced PSN in surface seawater calculated by modeling results and World Ocean Atlas 2013 nutrient dataset, and the well-established quantitative relationship between Chl a and PSN obtained from microcosm experiments, we found a noticeable change in surface Chl a concentrations due to N deposition derived from marine traffic in the NWPO, particularly in the coastal waters of the Yellow Sea and open oceans. This work attempts to establish a direct link between marine productivity and air emissions from shipping.

Zn-doped ZrO2/TiO2 porous coatings (Zn-ZrO2/TiO2) were prepared on the surface of titanium alloy (Ti6Al4V) by a hybrid approach of magnetron sputtering and micro-arc oxidation (MAO). The microstructures, phase constituents and elemental states of the coating were investigated by scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results demonstrate that the Zn-ZrO2/TiO2 coatings are porous and its thickness is approximately 13μm. The major phases in the oxidation coating are tetragonal ZrO2 (t-ZrO2), cubic ZrO2 (c-ZrO2) and rutile TiO2. XPS result reveals that Zn exists as ZnO in the Zn-ZrO2/TiO2 coatings. The biological experiments indicate that Zn-ZrO2/TiO2 coatings exhibit not only excellent antibacterial property against Gram-positive Staphylococcus aureus (S. aureus), but also favorable cytocompatibility. In addition, the corrosion resistance of the coating is also appreciably improved in the simulated body fluids (SBF), which can ensure better biocompatibility in body fluids.

To assess the relative contributions of traffic emission and other potential sources to high levels of atmospheric ammonia (NH3) in urban areas in the wintertime, atmospheric NH3 and related pollutants were measured at an urban site, ∼300 m from a major traffic road, in northern China in November and December 2015. Hourly average NH3 varied from 0.3 to 10.8 ppb with an average of 2.4 ppb during the campaign. Contrary to the common perspective in literature, traffic emission was demonstrated to be a negligible contributor to atmospheric NH3. Atmospheric NH3 correlated well with ambient water vapor during many time periods lasting from tens of hours to several days, implying NH3 released from water evaporation is an important source. Emissions from local green space inside the urban areas were identified to significantly contribute to the observed atmospheric NH3 during ∼60% of the sampling times. Evaporation of predeposited NHx through wet precipitation combined with emissions from local green space likely...

In a stratified water column, the nitracline is a layer where the nitrate concentration increases below the nutrient-depleted upper layer, exhibiting a strong vertical gradient in the euphotic zone. The subsurface chlorophyll maximum layer (SCML) forms near the bottom of the euphotic zone, acting as a trap to diminish the upward nutrient supply. Depth and steepness of the nitracline are important measurable parameters related to the vertical transport of nitrate into the euphotic zone. The correlation between the SCML and the nitracline has been widely reported in the literature, but the analytic solution for the relationship between them is not well established. By incorporating a piecewise function for the approximate Gaussian vertical profile of chlorophyll, we derive analytical solutions of a specified nutrient–phytoplankton model. The model is well suited to explain basic dependencies between a nitracline and an SCML. The analytical solution shows that the nitracline depth is deeper than the depth of the SCML, shoaling with an increase in the light attenuation coefficient and with a decrease in surface light intensity. The inverse proportional relationship between the light level at the nitracline depth and the maximum rate of new primary production is derived. Analytic solutions also show that a thinner SCML corresponds to a steeper nitracline. The nitracline steepness is positively related to the light attenuation coefficient but independent of surface light intensity. The derived equations of the nitracline in relation to the SCML provide further insight into the important role of the nitracline in marine pelagic ecosystems.

A healthy ecosystem depends on the coordination of ecosystem structure and function. The coordination among ecosystem components, however, is seldom taken into account in current ecosystem health assessments (EHA). Neglect of such coordination may lead to large degrees of uncertainty in EHA and fail to support ecosystem management. We propose an approach to quantify the level of dynamic mismatching between ecosystem structure and function and the impact on ecosystem health by incorporating the ecosystem coordination index into EHA. The coordination degree is calculated using variation coefficient of six proxies for ecosystem structure and functions. The ecosystem at Jiaozhou Bay, as a microcosm of China’s coast, has been documented to fluctuate from healthy to unhealthy status over the past three decades. The results indicate that there is a 3%−17% lower health level than that calculated by common methods used in the literature, indicating that the health of Jiaozhou Bay has become worse than expected. Habitat change contributes 20%−52% to ecosystem mismatches and is the most uncoordinated factor. Mismatch-related declines account for approximately one-fourth of the total ecological declines. Restoration scenarios that aim to resolve ecosystem mismatches could increase efficiency by about 50% compared to restoration scenarios that do not consider mismatches. This study investigates ecological declines in a coastal bay due to 30 years of rapid economic development. In doing so, this study provides novel insights and enhances our understanding of the reasons for failure in ecological restoration.

Atmospheric deposition can provide nutrients and potential toxicants to marine ecosystem, hence affecting ocean net primary productivity (NPP). Nonetheless, the interactive effects of mixed aerosol components on phytoplankton have rarely been reported. Here we explored the combined effects of iron (Fe) and copper (Cu) on NPP over the East China Sea. In aerosol addition mesocosm experiments, phytoplankton growth was suppressed under high aerosol Cu but was increased when high Cu was accompanied by high Fe in aerosols. A time series of soluble aerosol Fe and Cu deposition was obtained and compared to regional chlorophyll a (Chl a) abundances from Moderate Resolution Imaging Spectroradiometer/Aqua. Strong positive correlations were observed between the dry flux ratios of soluble Fe/Cu and Chl a abundances in the large offshore area, whereas these variables were uncoupled in coastal regions where riverine input and upwelling dominated the biogeochemistry. Current work provides insight into the complex linkage between atmospheric deposition and marine productivity.

Turbulent momentum flux in the typhoon boundary layer was measured at a turbulent flux tower in Southeast China using an eddy covariance technique during the passage of typhoons Fanapi and Megi in 2010. The anemometers were mounted on the cantilever bracket at the height of 26.6 m, 42.4 m, 60.4 m and 82.9 m. The momentum flux in the typhoon boundary layer decreased with increasing height during the two typhoon passages. The decrease was nearly linear during the passage of the Typhoon Fanapi. However, in the boundary layer of the Typhoon Megi, the momentum flux at 26.6 m height was much greater than that at 42.4 m height. The cospectra of wind components showed that the enhanced flux at the bottom of the boundary layer was caused by small scale turbulence with frequency in the range of 0.1–1 Hz and can be explained by the turbulent energy accumulation of small scale turbulence. This article is protected by copyright. All rights reserved.

In this study, a one-dimensional physical-biogeochemical coupled model was established to investigate the responses of the upper ocean to Typhoon Damrey in the basin area of the South China Sea. The surface chlorophyll a concentration (Chl a) increased rapidly from 0.07 to 0.17 mg m−3 when the typhoon arrived and then gradually reached a peak of 0.61 mg m−3 after the typhoon's passage. The subsurface Chl a decreased from 0.34 to 0.17 mg m−3 as the typhoon arrived and then increased gradually to 0.71 mg m−3. Analyses of model results indicated that the initial rapid increase in the surface Chl a and the decrease in the subsurface Chl a were caused mainly by physical process (vertical mixing), whereas the subsequent gradual increases in the Chl a in both the surface and subsurface layers were due mainly to biogeochemical processes (net growth of phytoplankton). The gradual increase in the Chl a lasted for longer in the subsurface layer than in the surface layer. Typhoon Damrey yielded an integrated primary production (IPP) of 6.5 × 103 mg C m−2 (~14% of the annual IPP in this region).

We have synthesized sodium tris(alkoxy)benzoates in which one of the three alkyl chains branches further into three C18H37 chains. These AB5 hyperbranched minidendrons melt directly into a body-centred cubic (BCC) mesophase formed by spherical “micelles”. In contrast, their non-branched counterparts display various mesophases before they turn into BCC upon heating. This agrees with the predictions from a numerical geometric model that relates the shape of the molecular wedge to the type of mesophase they adopt. The spheres were found to shrink in volume upon heating and expand upon cooling, as molecules, in some cases nearly half of them, are ejected and reintegrated in the spheres. The ejection of dendrons is caused by their lateral thermal expansion. The BCC appears to be the ultimate mesophase for the extremely divergent wedges such as the hyperbranched minidendrons. In dendrons with chains of unequal length, the sphere size is fixed by the shorter chains, the longer ones back-folding or interdigitating to effectively widen the wedge. This new understanding of their assembly will help in designing new dendrons, e.g. for better encapsulation of guest molecules.

Objective The purpose of this work was to explore the enhancement effect of zinc doped mesoporous silica nanoparticles (Zn-MSNs), which could form micromechanical interlocking with resin matrix and sustainably release Zn2+, on the mechanical and antibacterial properties of the dental resin composites. Methods Zn-MSNs were prepared by a sol–gel method, and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption/desorption. The mechanical properties of the dental composites reinforced by Zn-MSNs were measured by a universal mechanical testing machine. Antibacterial activities of dental composites were evaluated by both qualitative and quantitative analysis using Streptococcus mutans (S. mutans). The cytotoxicity of the Zn-MSNs filled dental composites was investigated by osteoblasts (OBs). Results The synthesized Zn-MSNs possessed good monodispersity with an average particle size of about 138 nm. The mechanical properties of the composites gradually increased with the increase of the content of Zn-MSNs. The flexural strength, flexural modulus, compressive strength and micro-hardness of the composites containing 15 wt% Zn-MSNs were 31.21%, 50.47%, 53.83% and 26.79% higher than the samples with no Zn-MSNs, respectively. The antibacterial performance was significantly improved by the addition of Zn-MSNs and the antibacterial rate of the composite with 15 wt% of Zn-MSNs reached 100%. Cytotoxicity tests revealed that all the composites were biocompatible during OBs incubation. Significance The prepared Zn-MSNs can effectively improve the mechanical and antibacterial properties of the dental resin composites.

Decadal trends of atmospheric ammonia (NH3) and their potential causes were explored through the analysis of monitored data collected at 15 sites in the United States and 7 sites in Canada. Large percentage increases in the annual average concentration of atmospheric NH3, for example, >100% at 6 sites and 40–100% at 10 sites, were observed over the most recent 8–13 year period. In contrast, a decrease or a narrow variation in NH3 emissions was reported at the state or provincial level in both countries during the same period. Decreased emissions of SO2 and NOx across North America in the past decade would have reduced the chemical loss of atmospheric NH3 to form particulate NH4+. Such a chemical mechanism was verified through regression analysis at about half of the monitored sites, where the increasing trends in atmospheric NH3 were partially explained by the reduced NH4+. Excluding the reduced contribution from this chemical loss to generate the adjusted annual NH3 concentration through two approaches, no decreasing trends can be obtained to align those in emissions at most sites, implying that other factors also contributed to the increase in the annual NH3 concentration. Correlation analysis results implied that enhanced drought conditions and increased ambient temperatures also likely contributed to the increasing trend in the annual NH3 concentration at some sites. The large percentage increases in the annual NH3 concentration cannot be fully explained by all the identified causes, leading to oppugning the reality of the decrease in NH3 emissions reported across North America in the recent decade.

Triple-negative breast cancer (TNBC), defined by the lack of expression of estrogen, progesterone, and ERBB2 receptors, has the worst prognosis of all breast cancers. It is difficult to treat owing to a lack of effective molecular targets. Here, we report that the growth of TNBC cells is exceptionally dependent on PICH, a DNA-dependent ATPase. Clinical samples analysis showed that PICH is highly expressed in TNBC compared to other breast cancer subtypes. Importantly, its high expression correlates with higher risk of distal metastasis and worse clinical outcomes. Further analysis revealed that PICH depletion selectively impairs the proliferation of TNBC cells, but not that of luminal breast cancer cells, in vitro and in vivo. In addition, knockdown of PICH in TNBC cells induces the formation of chromatin bridges and lagging chromosomes in anaphase, frequently resulting in micronucleation or binucleation, finally leading to mitotic catastrophe and apoptosis. Collectively, our findings show the dependency of TNBC cells on PICH for faithful chromosome segregation and the clinical potential of PICH inhibition to improve treatment of patients with high-risk TNBC.

The updated concentrations of atmospheric particles (N cn ) and the concentrations of cloud condensation nuclei (N ccn ) over the northwestern Pacific Ocean (NWPO) were important to accurately evaluate the influence of aerosol outflow from the Asian continent on the climate by considering rapid changes in emissions of air pollutants therein. However, field observations were scarce in the last two decades. We conducted a cruise campaign over the NWPO to simultaneously measure N cn , N ccn and the size distribution of aerosol particles from DOY 81 to DOY 108 of 2014. The mean values of N ccn at supersaturation (SS) of 0.2 % and 0.4 % were 0.68 ± 0.38×10 3 cm −3 and 1.1 ± 0.67×10 3 cm −3 , respectively, with an average for Ncn of 2.8 ± 1.0×10 3 cm −3 during the cruise over the NWPO, which were all approximately one order of magnitude larger than spring observations from two decades ago in the atmosphere of remote marine areas. The higher values, against the marine natural background reported in the literature, implied an overwhelming contribution from continental inputs. The calculated CCN activity ratios were 0.30 ± 0.11 and 0.46 ± 0.19 at SS of 0.2 % and 0.4 %, respectively, which were almost the same as those of upwind semi-urban sites. High N ccn and CCN activities were observed from DOY 98 to 102, when the oceanic zone received even stronger continental inputs. During the whole cruise period with the exclusion of biomass burning and dust aerosols, a good correlation between N ccn at 0.4 % SS and the number concentrations of > 60 nm particles (N > 60 nm ), with the slope of 0.98 and R 2 = 0.94, was obtained, and the corresponding effective hygroscopicity parameter ( k ) was estimated as 0.40. The bimodal size distribution pattern of the particle number concentration was generally observed during the entire campaign when the N > 90 nm varied largely. However, the N , accounting for approximately 1 / 3 of the total number concentration, varied narrowly, and two NPF events associated with vertical transport were observed, implying a pool of nucleation mode atmospheric particles aloft. Biomass burning (BB) and dust events were observed over the NWPO, but the contributions of BB and dust aerosols to N cn and N ccn were minor (i.e., 10 % or less) on the monthly time scale.

In this study, an oxide layer on Ti-based implants is fabricated by using a high current anodization (HCA) technique in the nitrate electrolyte. This layer is composed of micro-pits and nano-porous arrays in the honeycomb structure. The results show that both the roughness and the layer thickness are related to the reaction time, whereas the size of nano-pores has little to do with the anodization duration. Compared to the nano-tubular arrays constructed by the conventional anodization, this nano-porous layer shows significantly improved mechanical stability. Furthermore, the in vitro assay of osteoblasts shows that cells behaviors on this surface can be modulated by the topology of this special layer. A suitable hierarchical structure composed of micro-pits and nano-porous structure can significantly stimulate osteoblasts attachment, activity, spreading and ALP function. Therefore, this hierarchical surface layer may provide a promising approach, which endows the Ti-based implants with better stability and osseointegration.

Dust deposition can bring nutrients and trace elements to the upper ocean and affect phytoplankton growth and community structure. We conducted a comparative study using on-board microcosm experiments amended with varying amounts of dust (0.2, 1, and 2 mg L−1) in the East China Sea (eutrophic zone), the subtropical gyre (low-nutrient and low-chlorophyll zone, LNLC), and the Kuroshio-Oyashio transition region (high-nutrient and low-chlorophyll zone, HNLC) of the Northwest Pacific Ocean. The additions of dust supplied a considerable amount of nitrogen (N) and negligible phosphorus (P) relative to the seawater collected for incubation experiments (baseline), contributing to increases in Chlorophyll a with increasing dust additions. Significant linear correlations were observed between the net growth rates of larger cells (i.e., micro-size: >20 μm and nano-size: 2–20 μm) and available N (sum of baseline and added N) at each zone, demonstrating that phytoplankton size structure shifts towards larger cells with the increasing dust additions. In the experiments conducted in LNLC and HNLC zones, micro-sized phytoplankton (primarily consisting of diatoms) benefited most from dust additions. In the experiments conducted in eutrophic zone, however, the primary beneficiary was the nano-sized phytoplankton (primarily consisting of dinoflagellates). When a time lag of one day in relative abundance of diatoms (RAD, the abundance of diatoms divided by the sum of diatoms and dinoflagellates) relative to the N:P ratio was considered, we found the RAD increased substantially with increases in the N:P ratio until the ratio approached the Redfield ratio (N:P = 16:1), and then the RAD decreased gradually as the N:P ratio increased. This was ascribed to the lower sensitivity of dinoflagellates to nutrient shortage, relative to diatoms. Overall, our results suggested that the overwhelming input of N relative to P by dust deposition might cause significant ecological impacts by altering the N:P ratio of varying trophic seawaters.

In this study, ozonesonde data were used to evaluate the impact of different boundary conditions on the vertical distribution of ozone over urban Beijing. The comparison shows that the clean and static boundary conditions, referred to as PROFILE, apparently underestimate the ozone concentration over the upper troposphere and stratosphere, whereas the global chemical transport model (CTM) provides much more reasonable performance. Further investigation reveals that the boundary conditions exert larger impacts over areas with high altitudes and close distances to boundaries, such as the Tibetan Plateau, while they yield weak impacts on regions relatively far from the boundary, such as the North China Plain (NCP). Process analysis was conducted to investigate the modulation of physical and chemical processes on ozone formation in June 2017, illustrating that during the daytime of the high-O3 period, the photochemical reactions within the planetary boundary layer (PBL) almost become the only source favorable to ozone accumulation. Motivated by this phenomenon, we constructed a linear regression and found that the maximum daily 8-hr ozone (MDA8) ozone concentration was highly correlated with the surface ozone change rate and chemical reactions in the PBL during the pollution period, with MDA8 ozone exceeding 70 ppbv over NCP. Based on this relationship as well as the design of numerical experiments, we propose a strategy of dynamic emission control. Firstly, the emission reduction during the peak ozone formation period may weaken the fast chemical reactions in the PBL and subsequent surface ozone concentration. Secondly, emission reduction one or two days prior to an episode might achieve larger ozone reduction through the accumulation effect. Lastly, emission control outside of the NCP may surpass the local impact under favorable meteorological conditions. Therefore, the efficacy of dynamic emission control was striking when both the accumulation and transport effect were taken into consideration.

The electrochemical stability of Ni-Ti-O nanoporous layers anodically grown on the equiatomic NiTi alloy is assessed by immersion in deionized water and phosphate buffered saline and the influence of immersion on the corrosion behavior and biological properties is studied systematically. The morphology, chemical composition, and microstructure of the layers exhibit no obvious change even after immersion for 60 days in the two media and the corrosion resistance, antibacterial ability, and cytocompatibility are retained as well. These findings indicate the Ni–Ti–O nanoporous layers are stable and have large potential as coatings on NiTi biomedical implants.

North Pacific ocean desert (NPOD) refers to the subtropical North Pacific Ocean of low chlorophyll-a (Chl-a) concentrations, as the largest ocean desert globally. Studies have suggested a development of NPOD over recent decades based on limited evidences from in-field measurements and yet elusive mechanism. In this study, we characterize intensity, area and position of the NPOD from year 1998 to 2018, and investigate its control by the coherent climate processes, based on an available, longest satellite observations of Chl-a concentration. Our results suggested that NPOD oligotrophication and expansion processes were correlated with warming upper oceans in most part of the NPOD, except for the SW NPOD area where the Chl-a variations were linked with regional change in sea surface heights. Moreover, based on our analysis, insignificant shift but only NW-SE variability of the NPOD mean position was likely controlled by the Pacific decadal oscillation processes.

Magnesium (Mg) has been considered as the next-generation orthopedic implant material due to its biodegradability, but high degradation rate and severe cytotoxicity hinder its clinical application. Preparing micro-arc oxidation (MAO)/octacalcium phosphate (OCP) composite coating is considered as an ideal approach to solve the problems. In this work, nanostructured OCP coatings with variable structures were prepared facilely on MAO coated Mg by chemical deposition (CD) in a simple trace PO43- ion contained Ca(NO3)2 solution. The results show that nanostructured OCP grows and covers the MAO coating completely after CD. The morphology and thickness of OCP coating can be regulated by varying deposition time. The thinnest OCP coating with a fine structure is observed after 0.5 h of deposition, which shows the best cytocompatibility. Extending deposition time roughens the surface structure and thickens the coatings. The thickest OCP coating with a coarse structure can be obtained after 2 h of deposition, which shows the best corrosion resistance and mineralization. These results clearly indicate the functionality of the OCP coating can be easily tailored only by varying deposition time to meet different clinical requirements.

The numerous advantages of hydrogel make it possible to apply as dressing. However, it is challenging in designing hydrogels with desired antibacterial activity and enhanced mechanical properties at the same time. Herein, a graphene oxide/rose bengal/polyvinyl alcohol hybrid hydrogel (β-GO/RB/PVA HD) is prepared by freezing and thawing a mixed polyvinyl alcohol (PVA) solution of rose bengal (RB) immobilized with chitosan microspheres (CM) and a modified graphene oxide network (β-GO). The mechanical properties and light-triggered antibacterial activity of hydrogel are systematically evaluated. The β-GO inorganic network interpenetrate into the PVA porous structure, which significantly improves the mechanical properties of hydrogel. The hyperthermia generated by β-GO under 808 nm light irradiation combined with reactive oxygen species (ROS) produced by RB under 550 nm light irradiation give rise to excellent antibacterial activity requiring irradiation for only 10 min as demonstrated by our experiments conducted in vitro and in vivo. Meanwhile, β-GO/RB/PVA HD exhibits outstanding biocompatibility and water-absorbing capacity. More importantly, the hybrid hydrogel can significantly accelerate bacteria-accompanied wound healing. The results demonstrated that the hybrid hydrogel could be a promising wound dressing for preventing bacterial infection.

Blood coagulation and inflammation are the earliest biological responses to implant surfaces. Implant nano-surfaces can significantly impact the osseointegration through the influence on the early phase of bone regeneration. However, the interplay between blood clot property and inflammatory reaction on nanosurfaces is rarely understood. Herein, titania nanotube arrays (TNAs) with different diameters are fabricated on titanium. In vitro evaluation with the whole blood indicates that TNA with a diameter of 15 nm (TNA 15) enables noteworthy platelet activation resulting in distinct clot features compared with that of pure Ti and TNA with a diameter of 120 nm (TNA 120). Further co-culture with macrophages on the clot or in the clot-conditioned medium shows that the clot on TNA 15 downregulates the inflammation and manipulates a favorable osteoimmunomodulatory environment for osteogenesis. In vivo studies further demonstrate that TNA 15 could downregulate the inflammation-related genes while upregulating growth metabolism-related genes in an early healing hematoma. Additionally, TNA 15 promotes de novo bone formation with improved extending of osteocyte dendrites, demonstrating the desired osseointegration. These findings indicate that surface nano-dimensions can significantly influence clot formation and appropriate clot features can manipulate a favorable osteoimmunomodulatory environment for bone regeneration and osseointegration.

Background The aim of this study was to analyze the clinical features and laboratory indices of patients with coronavirus disease (COVID-19) and explore their association with the severity of the disease. Material/Methods A total of 61 patients with COVID-19 were divided into groups with common symptoms and with severe diseases, and clinical data were collected to analyze and compare the differences between them. Results In patients with severe COVID-19, compared with the common group, lymphocyte count and albumin levels were lower, and aspartate aminotransferase (AST), blood urea, blood creatinine, lactate dehydrogenase (LDH), and C-reactive protein (CRP) levels, and prothrombin time (PT) were elevated (all P8.9 (OR, 0.026; 95% CI: 0.002–0.349; P=0.006) were independent risk factors for COVID-19 severity. Conclusions Elevated CRP and prolonged PT, and an MPVLR >8.9 were independent risk factors for COVID-19 severity.

Copper/cerium bimetallic catalyst is an efficient material for the removal of carbon monoxide, while the rapid deactivation under moisture-rich conditions in the conventional thermal-catalysis limited its wide application. Here, we investigated the plasma-assisted catalytic oxidation of CO over Cu/Ce oxides supported on γ-Alumina in comparison with the conventional thermal catalytic oxidation. The TOF values of the Cu/Ce catalysts showed that the plasma catalysis was the better catalytic system for CO oxidation (2.96 s−1 for thermal catalysis, 5.13 s−1 for plasma catalysis). Importantly, the energy barriers for plasma catalysis were much lower than that for thermal catalysis, especially under moisture-rich conditions (e.g. 130.3 kJ/mol versus 246.1 kJ/mol under 9.8 vol% water vapor). The loss of activity caused by water was reversible for the plasma process, but not for the thermal process. The Cu/Ce catalyst remained good stability within 60 h in the presence of 6.1% water for plasma oxidation, while the thermal catalytic activity declines gradually. Also, water could inhibit the formation of gas byproducts (O3 and NOx). The promoting role of plasma could be mainly ascribed to the enhanced strength of oxygen mobility and plasma-assisted decomposition of surface carbonate in the presence of water, as revealed by the in-situ NTP-TPR, XPS, and the ex-situ DRIFTS analyses.

To improve estimation of the dry deposition flux (Fd) of nitrogen and phosphorus over the ocean, the concentrations of NO2−, NO3−, NH4+, and PO43− in aerosol particles were measured from 2005 to 2017, and their deposition rates (Vd) were modeled over the marginal seas of China and the northwest Pacific (NWP). Combined with the modeled rates and the measured size distribution, the Vd values of NO2−, NO3−, NH4+, and PO43− over the studied ocean region were calculated to at 0.92 ± 0.06, 0.95 ± 0.08, 0.68 ± 0.03 and 0.65 ± 0.06 cm·s−1 on average, respectively. The spatial variation in Vd for these species was dependent on the wind speed and mass concentration size distribution. Based on the multiyear observations over the region, the average concentrations of atmospheric NO2−, NO3−, NH4+, and PO43− were 2.07 ± 1.58 nmol·m−3, 58.5 ± 44.3 nmol·m−3, 107.9 ± 56.7 nmol·m−3 and 1.13 ± 1.10 nmol·m−3, respectively. The estimated Fd of NO2− was lower than 1 μmol·m2·d−1 in most ocean regions, although the Fd of NO3−, NH4+ and PO43− were 42.74 ± 25.02, 57.40 ± 29.50 and 0.66 ± 0.72 μmol·m2·d−1, respectively. Except for the South China Sea, the Fd values of NO3− and NH4+ were 3–6 times higher over the marginal seas than the NWP while the PO43− flux was only high over the Yellow and Bohai Seas. The dissolved N/P ratio influx varied from 84 to 338, indicating that N was equivalent to the relative abundance of P during the atmospheric input to the China marginal seas and the NWP. Our results showed that the long-term input of atmospheric anthropogenic nutrients would cause different influences on the stoichiometric ratios of nutrients and primary productivity between marginal seas and open ocean.