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This work provides an environmental friendly route to fabricate ternary silver/silver oxide/zinc oxide (Ag/Ag2O/ZnO) photocatalyst with assistance of bovine serum albumin (BSA). The structural analysis indicates that Ag/Ag2O/ZnO photocatalyst is a 3D-flowerlike architecture. Nanoparticles composed of Ag and Ag2O in diameter about 40 nm attach on the surfaces of ZnO “petals” and form a heterojunction structure with ZnO. The ultraviolet-visible (UV–vis) spectra and photoluminescence (PL) spectra show that the obtained Ag/Ag2O/ZnO nanocomposite displays an enhanced visible-light absorption and a decreased fluorescence emission compared to that of ZnO. The photocatalytic performance of Ag/Ag2O/ZnO nanocomposite was evaluated by photocatalytic degradation of methylene blue (MB) under simulated visible light irradiation. The results indicate that Ag/Ag2O/ZnO nanocomposite exhibits better photocatalytic activity than that of single- and two-component photocatalysts including ZnO, Ag2O, TiO2 and Ag/ZnO. Ag/Ag2O/ZnO nanocomposite also has a good recycling stability and still maintains a high degradation efficiency (85%) after four recycles. The improved photocatalytic activity is credited to the synergistic effect of Ag, Ag2O and ZnO nanophases in the Ag/Ag2O/ZnO heterojunction, which results in an effective charge separation and a low recombination of photo-induced electron-hole pairs.

The present work reports on the hydrothermal synthesis of nanosheets on biomedical NiTi alloy in pure water. The results show rhombohedral NiTiO3 nanosheets with thickness of 6 nm can be grown at 200 °C. Hydrothermal treatment enhances the corrosion resistance of the NiTi alloy. 30 min of the treatment significantly reduces Ni ion release, while prolonged hydrothermal time results in increased Ni ion release because of the growth of the nanosheets with large specific surface area. Excitingly, the nanosheets can well support cell growth, which suggests the release amount can be well tolerated. Good corrosion resistance and cytocompatibility combined with large specific surface area render the nanosheets promising as safe and efficient drug carriers of the biomedical NiTi alloy.

Angiosperm mitochondrial genomes (mitogenomes) are notable for their extreme diversity in both size and structure. However, our current understanding of this diversity is limited, and the underlying mechanism contributing to this diversity remains unclear. Here, we completely assembled and compared the mitogenomes of three kiwifruit (Actinidia) species, which represent an early divergent lineage in asterids. We found conserved gene content and fewer genomic repeats, particularly large repeats (>1 kb), in the three mitogenomes. However, sequence transfers such as intracellular events are variable and dynamic, in which both ancestral shared and recently species-specific events as well as complicated transfers of two plastid-derived sequences into the nucleus through the mitogenomic bridge were detected. We identified extensive whole-genome rearrangements among kiwifruit mitogenomes and found a highly variable V region in which fragmentation and frequent mosaic loss of intergenic sequences occurred, resulting in greatly interspecific variations. One example is the fragmentation of the V region into two regions, V1 and V2, giving rise to the two mitochondrial chromosomes of Actinidia chinensis. Finally, we compared the kiwifruit mitogenomes with those of other asterids to characterize their overall mitogenomic diversity, which identified frequent gain/loss of genes/introns across lineages. In addition to repeat-mediated recombination and import-driven hypothesis of genome size expansion reported in previous studies, our results highlight a pattern of dynamic structural variation in plant mitogenomes through global genomic rearrangements and species-specific fragmentation and mosaic loss of intergenic sequences in highly variable regions on the basis of a relatively large ancestral mitogenome.

Nearly equiatomic nickel–titanium (NiTi) alloy is an ideal implant biomaterial because of its shape memory effect, superelasticity, low elastic modulus as well as other desirable properties. However, it is prone to infection because of its poor antibacterial ability. The present work incorporated Cu into Ni–Ti–O nanopores (NP–Cu) anodically grown on the NiTi alloy to enhance its antibacterial ability, which was realized through electrodeposition. Our results show that incorporation of Cu (0.78 at%–2.37 at%) has little influence on the NP diameter, length and morphology. The release level of Cu ions is in line with loadage which may be responsible for the improved antibacterial ability of the NiTi alloy to combat possible bacterial infection in vivo. Meanwhile, the NP–Cu shows better cytocompatibility and even can promote proliferation of bone marrow mesenchymal stem cells (BMSCs), up-regulate collagen secretion and extracellular matrix mineralization when compared with Cu-free sample. Better antibacterial ability and cytocompatibility of the NP–Cu render them to be promising when serving as NiTi implant coatings.

We describe a strategy to fabricate a hydrogel-based microvascular construct by direct writing alginate bioink inside the viscous pre-polymer of hydrogels, which acts as a support bath. As the print needle translates through the polymers, the extruded alginate instantaneously forms calcium alginate hydrogel (Ca-Alg) templates deposited within the bath. This phase change allows the formed templates to be anchored within the pre-polymers, while maintaining their structure. After the printing process, the pre-polymers are solidified to form a mechanically robust hydrogel. Finally, a hydrogel construct with embedded microchannels is generated by liquefying and removing the Ca-Alg templates. Using this method, not only the alginate ink alone can be directly printed within the engineered constructs, but also the size and shape of the formed microchannels are controllable. Furthermore, a confluent endothelial layer for the generation of vascular networks can be constructed by adhering and proliferating endothelial cells on the channel linings. This strategy demonstrates a promising technique for rapid construction of in vitro vasculatures, which would provide a versatile platform for a wide array of applications such as tissue engineering, organ-on-a-chip and drug screening.

The characteristics, distributions, and direct radiative effects (DRE) of marine aerosols in the western Pacific Ocean over East Asia during the period from 17 March to 22 April 2014 were investigated by an online-coupled regional atmospheric chemistry/aerosol-climate model RIEMS-Chem (Regional Integrated Environmental Model System with Chemistry). The emissions and relevant processes of sea salt, marine primary organic aerosol (MPOA), sulfate and Methyl sulfonic acid (MSA) produced from dimethylsulfide (DMS) were parameterized and coupled with RIEMS-Chem. The model results for total aerosol masses (PM10 and PM2.5), inorganic and carbonaceous aerosols, gas precursors, and aerosol optical depth (AOD) were compared with various observational data sets including a research cruise Dongfanghong II from the Yellow Sea to the open oceans, near-surface aerosol and gas concentrations from the Acid Deposition Monitoring Network in East Asia (EANET) and China National Environmental Monitoring Center (CNEMC), and AOD from the Aerosol Robotic Network (AERONET). Model comparisons demonstrated a generally good skill of the RIEMS-Chem in representing the temporal and spatial variations of these variables. The distributions of marine aerosols were characterized by the maximum sea salt concentration up to 70 μg m−3 in the ocean northeast of Japan, the maximum concentration of MPOA >2 μg m−3 in the East China Sea and in portions of the northwest Pacific (NWP) region, and the maximum DMS-produced aerosol concentration >0.3 μg m−3 in the southern parts of the ocean. It was noteworthy that marine aerosols can be easily transported to the inland areas of south China. The clear-sky DREs by sea salt ranging from −9 to −17 W/m2 occurred in the open oceans northeast of Japan, comparable to the DREs of −10 ~ −20 W/m2 by anthropogenic aerosols, whereas the DREs by MPOA were strongest (up to −1.3 Wm−2) in the East China Sea and the oceans northeast of Japan due to active phytoplankton blooms there and comparable in magnitude to the DREs by sea salt (around −3 Wm−2) in the East China Sea. The maximum DRE by the DMS-produced aerosols was −0.4 Wm−2 mainly in the northern parts of the South China Sea. Sea salt exhibited an increasing radiative importance from the China marginal seas to the open oceans, accounting for 10% and 33% of the DREs by all aerosols, respectively. Under all-sky conditions, the sum of DREs by all the marine aerosols were estimated to be −2.2 W/m2, −3.5 W/m2, −2.3 W/m2, and −4.3 W/m2 averaged over the entire domain, ocean, East China Sea, and the NWP region, accounting for 20%, 27%, 13%, and 36% of the DREs by all aerosols, respectively, which demonstrated the important role of marine aerosols in modulating shortwave radiation in springtime in the western Pacific Ocean which was just downwind of the Asian continent with large amounts of anthropogenic and dust emissions.

Akebia trifoliata is perennial and deciduous vines, its fruit, seed, stem and root have been used in Chinese herbalism for at least 2000 years. As a high-value medicinal, the A. trifoliata should be exploited and domestication is underway as edible fruit crop. In the present study, a wild seedlings population and a three-generation selected population have been evaluated and characterized for a set of morphological traits in order to evaluate the effectiveness of recurrent selection method in achieving selection progress, maintaining genetic variability, and increasing the potential for selection of superior genotypes in A. trifoliata. The result showed that the fruit weight increased 33.16% which ranged from 237.67 to 598.54 g with an average of 310.86 g in the selected population. The leaf of A. trifoliata in the selected population became much larger range from 91.24 to 170.43 mm with an average of 117.33 mm, the leaf length, leaf width and petiole length increased 15.72%, 7.91% and 9.33%, respectively. Correlation analysis showed most of the measured characters are highly correlated each other. The principal component analysis (PCA) indicated that the first five components can explain 83.90% of the total variance. Cluster analysis revealed two distinct clusters among the selected population. The present study showed the effectiveness of the recurrent selection method when applied in A. trifoliata breeding, although some refinements in the selection program could further improve its efficiency.

The species of Akebia Decne are well-known medicinal plants and have been used in Chinese herbalism for at least 2000 years. The Akebia fruits have a delicious flavor and high nutritional value and are especially rich in antineoplastic, diuretic and antiphlogistic properties, making them worthy of being exploited as a new high-value crop. However, the nature habitats of the Akebia species have been fragmented due to rapid and intensive expansion of agricultural land. In this study, population genetics based on simple sequence repeat markers were conducted on the three most economically important Akebia species in order to reveal the genetic effects of habitat fragmentation to gain useful information for conservation and management of genetic resources of Akebia. Three Akebia species maintained high within-population genetic variation and low level of genetic differentiation. Mantel’s test indicated that there was a significantly positive correlation between genetic distance and geographic distance. Our results reveal the resilience of genetic diversity within extant populations of three Akebia species to chronic forest fragmentation. For breeding purpose, germplasm collection for sampling as many individuals as possible from many populations to maximize genetic diversity of the species is recommended. In addition, natural introgression events have been revealed by Cluster and Structure analysis where admixed ancestry occurred across three marginal populations of A. trifoliata ssp. australis, suggesting these populations should be given priority for germplasm collection.

Inflammatory reactions and the functionality of endothelial cells (ECs) on the surfaces of coronary stents are critical in the prevention of in-stent restenosis and subsequent neoatherosclerosis. However, the interactions between immune cells and ECs on modified coronary stent surfaces have long been underestimated. In the present study, silicon (Si)-doped titania nanotube arrays (TNA-Sis) were obtained via the facile anodization of magnetron-sputtered Ti-Si coatings. The synergetic effects of titania nanotube arrays (TNAs) and chemical cues (Si) on the functionality of macrophages (MΦs)/ECs and their cross-talk were investigated. The results indicated that TNA-Sis specimens, in comparison with TNAs alone, not only promoted the initial vitality of ECs, enhanced the expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO), and activated multiple cell signaling pathways (vWF, PECAM, eNOS), but also induced a favorable immune response through the polarization of MΦs to a pro-healing M2 phenotype via the activation of cell autophagy, resulting in the downregulation of inflammatory reactions. This beneficial immune response further facilitated cross-talk between ECs and MΦs, resulting in profoundly increased functionality of ECs on TNA-Sis surfaces. This study demonstrated that using TNA-Sis surface coatings for coronary stents may be a promising strategy to prevent in-stent restenosis.

An online coupled regional chemistry-aerosol-climate model was developed and applied to explore the distribution, evolution and indirect effects of marine primary organic aerosols (MPOA) over East Asia during the period from 12 March to 22 April 2014. Model results were compared with a variety of observations from ground measurement, cruise experiment and satellite retrievals, which demonstrated the model was capable of reproducing reasonably well the major features in meteorological variables, gas species, aerosol components and cloud properties in the western Pacific Ocean in springtime. Active bloom events were observed in the western Pacific Ocean during the study period, with mean surface seawater Chlorophyll a (Chl-a) concentrations up to 10 mg m−3 in the Yellow Sea, East China Sea, Sea of Japan, as well as the ocean northeast of Japan. The mean surface MPOA concentration was simulated to be up to 2.5 μg m−3 in the East China Sea, followed by that in the ocean northeast of Japan, and about 0.5 μg m−3 in the coastal areas of east China. MPOA generally caused increases in the cloud condensation nuclei (CCN), cloud droplet number concentration (CDNC), cloud optical depth (COD) and cloud liquid water path (CLWP), but decrease in the cloud droplet effective radius (CDER). The above changes in cloud properties induced a negative indirect radiative effect (IRE), with the mean values being −5.3 Wm-2, −8.2 Wm-2 and -12.2 Wm-2 over the ocean, East China Sea and the north western Pacific Ocean, which accounted for about 40%, 35% and 51% of the IRE due to all aerosols in these regions, respectively. It was noteworthy that the MPOA induced IRE was −3.6 Wm-2 in east China, accounting for 20% of the IRE by all aerosols and the percentage contribution was about 32% for the whole domain, suggesting its important influence on cloud and radiation during the study period. The sensitivity of MPOA activation to the factors affecting hygroscopicity and surface tension was examined by sensitivity simulations. The indirect effects of MPOA tended to suppress precipitation in most of the domain, with the maximum decrease in the accumulated precipitation up to 50 mm in parts of south China and the East China Sea. In terms of domain average, MPOA accounted for 16%, 22%, 18% of the precipitation reduction due to all aerosols over the land, ocean and the whole domain, respectively, indicating its nonnegligible influence on precipitation over East Asia in springtime 2014.

Impressive progress has been made on the development of magnesium alloys (Mg) implants in cardiovascular and orthopedic applications due to their good mechanical strength and biodegradable. In this paper, heparin and carboxymethyl chitosan were immobilized on alkali-treated Mg to improve the hemocompatibility and antibacterial activities. Electrochemical tests revealed that the surface modified Mg obviously improved the corrosion resistance. Additionally, the surface-functionalized Mg exhibited excellent antithrombotic and antibacterial activities.

New particle formation (NPF) induces a sharp increase in ultrafine particle number concentrations and potentially acts as an important source of cloud condensation nuclei (CCN). As the densely populated area of China, the Yangtze River Delta (YRD) region shows a high frequency of observed NPF events at the ground level, especially in spring. Although recent observational studies suggested a possible connection between NPF at the higher altitudes and ground level, the role played by vertical mixing, particularly in the planetary boundary layer (PBL) is not fully understood. Here we integrate measurements in Nanjing on 15-20 April 2018, and the NPF-explicit Weather Research and Forecast coupled with chemistry (WRF-Chem) model simulations to better understand the governing mechanisms of the NPF and CCN. Our results indicate that newly formed particles at the boundary layer top could be transported downward by vertical mixing as the PBL develops. A numerical sensitivity simulation created by eliminating aerosol vertical mixing suppresses both the downward transport of particles formed at a higher altitude and the dilution of particles at the ground level. The resulting higher Fuchs surface area at the ground level, together with the lack of downward transport, yields a sharp weakening of NPF strength and delayed start of NPF therein. The aerosol vertical mixing, therefore, leads to a more than double increase of surface CN

Angiogenesis, an essential prerequisite to osteogenesis in bone repair and regeneration, can be mediated by immunoregulation of macrophages. Magnesium and its alloys are promising biodegradable bone implant materials and can affect immunoregulation of macrophages by the degradation products (magnesium ions). Nevertheless, the mechanism of macrophage-derived exosomes stimulated by Mg ions in immunoregulation is still not well understood. Herein, 10–50 mM magnesium ions are shown to inhibit the macrophage viability and proliferation in a dose-dependent manner, but a high concentration results in macrophage apoptosis. The exosomes secreted by macrophages from magnesium ion stimulation inhibit angiogenesis of endothelial cells, as manifested by the suppressed cell viability, proliferation, migration, and tube formation, which arise at least partially from exosome-mediated downregulation of endothelial nitric oxide and the vascular endothelial growth factor. The findings reported in this paper suggest that the bio-functionality of biodegradable magnesium alloys must be considered from the perspective of immunoregulation of macrophage-derived exosomes. Our results also suggest potential cancer therapy by inhibiting tumor-associated angiogenesis.

Osteogenesis and angiogenesis are both important for implant osseointegration, which can be tailored by immunomodulation of macrophages. Zn, a novel biodegradable material, can modulate macrophage functions in its ionic form. However, whether macrophage-derived exosomes, novel carriers of intracellular communication, participate in the process is still unclear. The present work shows that Zn ions in the concentration range of 0-100 μM have no significant influence on macrophage viability, proliferation, morphology, and secretion amount of exosomes, but generally downregulate the gene expression of both M1 and M2 markers. The exosomes can be ingested continuously by osteoblasts and endothelial cells. The osteoblasts show the highest alkaline phosphatase activity after ingesting the exosomes derived from macrophages upon 4 μM Zn ion stimulation. In contrast, the endothelial cells migrate the furthest distance after ingesting the exosomes upon 20 μM Zn ion stimulation. These results indicate that Zn ions may vary the composition of macrophage-derived exosomes, which in turn affects the osteogenesis and angiogenesis. These findings are meaningful for the surface design of immunomodulatory biomaterials from the perspective of macrophage-derived exosomes.

It has been reported that air quality models largely underestimate PM

In this study, a methodology for satellite retrieval of cloud condensation nuclei (CCN) in shallow marine boundary layer clouds is presented and validated. This methodology is based on retrieving cloud base drop concentration (Nd) and updrafts (Wb), which are used for calculating supersaturation (S). The Nd is the activated CCN concentration in clouds at a given S. The accuracy of the satellite retrieval is validated against the surface-measured CCN of a cruise campaign over the heavily polluted northwest Pacific Ocean. Clouds which are coupled with the sea surface have good agreement between satellite retrieved Nd and surface-measured CCN after performing corrections for temperature and adiabatic fraction. This study broadens the applicability of the methodology from aerosol-limited to contaminated regions. The validation shows ±30% accuracy in retrieving CCN of 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 the relationships between CCN and cloud microphysical properties and reduce the uncertainty of radiation forcing caused by aerosol cloud interaction (ACI).

Current conventional treatment strategies for glioblastoma (GBM) have limited efficacy due to the rapid development of resistance to temozolomide (TMZ). It is particularly urgent to develop novel therapeutic strategies that can overcome TMZ resistance and provide patients with better prognoses. Here, a TMZ-resistant GBM cell strain and a mouse model of TMZ resistance are established as valuable tools to explore novel therapeutic strategies against TMZ resistance. Experimentally, p38MAPK inhibitor reduces the accumulation of F4/80

Medulloblastoma (MB) is one of the most common childhood malignant brain tumors (WHO grade IV), traditionally divided into WNT, SHH, Group 3, and Group 4 subgroups based on the transcription profiles, somatic DNA alterations, and clinical outcomes. Unlike WNT and SHH subgroup MBs, Group 3 and Group 4 MBs have similar transcriptomes and lack clearly specific drivers and targeted therapeutic options. The recently revised WHO Classification of CNS Tumors has assigned Group 3 and 4 to a provisional non-WNT/SHH entity. In the present study, we demonstrate that Kir2.1, an inwardly-rectifying potassium channel, is highly expressed in non-WNT/SHH MBs, which promotes tumor cell invasion and metastasis by recruiting Adam10 to enhance S2 cleavage of Notch2 thereby activating the Notch2 signaling pathway. Disruption of the Notch2 pathway markedly inhibited the growth and metastasis of Kir2.1-overexpressing MB cell-derived xenograft tumors in mice. Moreover, Kir2.1high/nuclear N2ICDhigh MBs are associated with the significantly shorter lifespan of the patients. Thus, Kir2.1high/nuclear N2ICDhigh can be used as a biomarker to define a novel subtype of non-WNT/SHH MBs. Our findings are important for the modification of treatment regimens and the development of novel-targeted therapies for non-WNT/SHH MBs.

Angiogenesis is critical for tissue repair and regeneration, including implant osseointegration. It is well known that macrophages exert immunomodulatory functions in angiogenesis. However, whether macrophage-derived exosomes participate in the process is still unclear. Cobalt (Co) ions are frequently used as implant additives to mimic hypoxic microenvironment, which can induce angiogenesis through stabilizing hypoxia inducible factor-1α (HIF-1α) of macrophages and endothelial cells (ECs). The present work attempts to investigate whether exosomes derived from macrophages upon Co ion stimulation can mediate angiogenesis and the possible mechanism. The results show that the exosomes promote endothelial migration and angiogenesis in vitro and in vivo, particularly when Co ion concentration is 200 μM. Further studies reveal that the exosomes upregulating nitric oxide (NO), vascular endothelial growth factor (VEGF), and integrin β1 expression may be the underlying mechanism of the observations. Our findings provide new insights for Co ion mediated macrophage-EC communication and surface design of biomaterials from the perspective of pro-angiogenesis.

Copper, a frequently used additive of implant materials, can alter macrophage phenotype thus directing the fate of the implants. Exosomes, secreted by mammalian cells, can target to recipient cells and mediate their functions. However, whether exosomes derived from macrophages upon copper ion stimulation can modulate angiogenesis, a key index for implant osseointegration, is still unclear. Herein, the influence of copper ions on macrophage-derived exosome secretion, ingestion behavior by endothelial cells, and angiogenic-induction ability is investigated. The results show copper ions (0–100 μM) have little influence on the secretion of macrophage-derived exosomes. Endothelial cells can uptake the exosomes from all the groups in a time-dependent manner. The exosomes have little influence on endothelial adhesion and proliferation, but can upregulate angiogenic ability of endothelial cells in vitro and in vivo, which may be related to trafficking of integrin β1. The results provide insight into the effect of copper ions on immunomodulatory mechanism of macrophages, which is important for implant design from the perspective of material compositions.

The complete chloroplast (cp) genome sequence of Actinidia eriantha was sequenced and assembled using Illumina paired-end data. The cp genome from A. eriantha is 156,964 bp in length, composed of a pair of 23,892 bp inverted repeat regions (IR) separated by a large single copy region (LSC) of 88,639 bp and a small single copy region (SSC) of 20,541 bp. The cp genome contained 113 unique genes, including 79 protein-coding genes, 30 tRNA genes, and four ribosomal RNA genes. The phylogenetic position of A. eriantha based the cp genome data was sister to the group A. rufa, A. deliciosa, and A. chinensis.

Stent implantation has become one of the most widely used methods for the treatment of cardiovascular diseases. However, endothelial dysfunction and abnormal inflammatory response following implantation may lead to delayed re-endothelialization, resulting in vascular restenosis and stent thrombus. To address the concerns, we constructed nanospindles composed of TiO2 and Ti4Ni2O through hydrothermal treatment of amorphous Ni-Ti-O nanopores anodically grown on NiTi alloy. The results show the treatment can significantly improve hydrophilicity and reduce Ni ion release, essentially independent of hydrothermal duration. The nanospindle surfaces not only promote the expression of endothelial functionality but also activate macrophages to induce a favorable immune response, downregulate pro-inflammatory M1 markers and upregulate pro-healing M2 markers. Moreover, nitric oxide (NO) synthesis, VEGF secretion, and migration of endothelial cells are enhanced after cultured in macrophage conditioned medium. The nanospindles thus are promising as vascular stent coatings to promote re-endothelization.

The impact of biogenic emissions on ozone and secondary organic aerosol (SOA) has been widely acknowledged; nevertheless, biogenic emissions emitted from urban landscapes have been largely ignored. We find that including urban isoprene in megacities like Beijing improves not only the modeled isoprene concentrations but also its diurnal cycle. Specifically, the mean bias of the simulated isoprene concentrations is reduced from 87% to 39% by adding urban isoprene emissions while keeping the diurnal cycle the same as that in non-urban or rural areas. Further adjusting the diurnal cycle of isoprene emissions to the urban profile steers the original early morning peak of the isoprene concentration to a double quasi-peak, i.e., bell shape, consistent with observations. The efficiency of ozone generation caused by isoprene emissions in urban Beijing is found to be twice as large as those in rural areas, indicative of vital roles of urban BVOC emissions in modulating the ozone formation. Our study also shows that in the future along with NOx emission reduction, isoprene emissions from urban landscapes will become more important for the formation of ozone in urban area, and their contributions may exceed that of isoprene caused by transport from rural areas. Finally, the impact of biogenic emissions on SOA is examined, revealing that biogenic induced SOA accounts for 16% of the total SOA in urban Beijing. The effect of isoprene on SOA (iSOA) is modulated through two pathways associated with the abundance of NOx emissions, and the effect can be amplified in future when NOx emissions are reduced. The findings of our study are not limited to Beijing but also apply to other megacities or densely populated regions, suggesting an urgent need to construct an accurate emission inventory for urban landscapes and evaluate their impact on ozone and SOA in air quality planning and management.

Organic aerosols from marine sources over the western Pacific Ocean of East Asia were investigated by using an online-coupled regional chemistry-climate model RIEMS-Chem for the entire year 2014. Model evaluation against a wide variety of observations from research cruises and in-situ measurements demonstrated a good skill of the model in simulating temporal variation and spatial distribution of particulate matter with aerodynamic diameter less than 2.5 μm and 10 μm (PM2.5 and PM10), black carbon (BC), organic carbon (OC), and aerosol optical depth (AOD) in marine atmosphere. The inclusion of marine organic aerosols apparently improved model performance on OC aerosol concentration, reducing the normalized mean biases from −19 % to −13 % (KEXUE-1 cruise) and −21 % to −3 % (Huaniao Island) over the marginal seas of east China, and from 33 % to 5 % (Dongfanghong II cruise) and from −13 % to 3 % (Chichijima Island) over remote oceans of the western Pacific. It was found that marine primary organic aerosol (MPOA) accounted for majority of marine organic aerosol (MOA) mass in the western Pacific. High MPOA emission mainly occurred over the marginal seas of China and remote oceans of the western Pacific northeast of Japan. The seasonality of MPOA emission is determined by the combined effect of Chlorophyll-a (Chl-a) concentration and sea salt emission flux, exhibiting the maximum in autumn and the minimum in summer in terms of domain average over the western Pacific. The annual mean MPOA emission rate was estimated to be 0.16×10−2 μg m−2 s−1, yielding an annual MPOA emission of 0.78 Tg yr−1 over the western Pacific, which potentially accounted for approximately 8~12 % of global annual MPOA emission. The regional and annual mean near surface MOA concentration was estimated to be 0.27 μg m−3 over the western Pacific, with the maximum in spring and the minimum in winter, resulting from the combined effect of MPOA emission, dry and wet depositions. Marine secondary organic aerosol (MSOA) produced by marine biogenic VOCs (isoprene and monoterpene) was approximately 1~2 orders of magnitude lower than MPOA. The simulated annual and regional mean MSOA was 2.2 ng m−3, with the maximum daily mean value up to 28 ng m−3 over the western Pacific in summer. MSOA had a distinct summer maximum and winter minimum in the western Pacific, generally consistent with the seasonality of marine isoprene emission flux. In terms of annual mean, 26 % of the total organic aerosol concentration was contributed by MOA over the western Pacific, with an increasing importance of MOA from the marginal seas of China (13 %) to remote oceans of the western Pacific (42 %). MOA induced a minor direct radiative effect (DRE), with a domain and annual mean of −0.21 W m−2 at the top of the atmosphere (TOA) under all-sky condition over the western Pacific, whereas the mean indirect radiative effect (IRE) due to MOA at TOA (IREMOA) was estimated to be −4.2 W m−2. MSOA contributed approximately 6 % of the annual and regional mean IREMOA over the western Pacific, with the maximum seasonal mean contribution up to 14 % in summer, which meant MPOA dominated the IREMOA. It was noteworthy that the IREMOA accounted for approximately 32 % of that due to all aerosols over the western Pacific of East Asia, indicating an important role of MOA in perturbing cloud properties and shortwave radiation in this region.

Background: Previous plant phylogeography in subtropical China mostly focused on rare and endangered species, whereas few studies conducted on the taxa with relatively wide distribution, especially for polyploid species. We used Actinidia chinensis complex, a widespread geographically woody liana of variable ploidy in subtropical China, to investigate its cytotype and haplotype distribution pattern based on three chloroplast fragments (ndhF-rpl132, ps16-trnQ and trnE-trnT). Macroevolutionary, microevolutionary and niche modeling tools were also combined to disentangle the origin and the demographic history of the species or cytotypes. Results: The ploidy levels of 3569 individuals from 128 populations sampled throughout the species distribution range were estimated using flow cytometry. The widespread cytotypes were diploids followed by tetraploids and hexaploids, while triploids and octaploids occasionally occurred in a few populations. Thirty-one chloroplast haplotypes were detected and the genetic diversity and genetic structure were great differences between the var. chinensis and var. deliciosa. Our results also revealed these two varieties (or ploidy races) inhabit significantly different climatic niche spaces. Ecological niche models (ENMs) indicate that all varieties’ ranges contracted during the Last Interglacial (LIG), and expanded eastward or northward during the Last Glacial Maximum (LGM). Conclusions: Pliocene and Plio-Pleistocene climatic fluctuations and vicariance may have played key roles in shaping the current population structure and historical demography in the A. chinensis complex. The polyploidization process also played an important role in the historical demography of the A. chinensis complex through improving their adaptability to environmental changes.

Background Plant phylogeographic studies of species in subtropical China have mainly focused on rare and endangered species, whereas few studies have been conducted on taxa with relatively wide distribution, especially polyploid species. We investigated the cytotype and haplotype distribution pattern of the Actinidia chinensis complex, a widespread geographically woody liana with variable ploidy in subtropical China comprising two varieties, with three chloroplast fragments DNA (ndhF-rpl132, rps16-trnQ and trnE-trnT). Macroevolutionary, microevolutionary and niche modeling tools were also combined to disentangle the origin and the demographic history of the species or cytotypes. Results The ploidy levels of 3338 individuals from 128 populations sampled throughout the species distribution range were estimated with flow cytometry. The widespread cytotypes were diploids followed by tetraploids and hexaploids, whereas triploids and octoploids occurred in a few populations. Thirty-one chloroplast haplotypes were detected. The genetic diversity and genetic structure were found to be high between varieties (or ploidy races) chinensis and deliciosa. Our results revealed that these two varieties inhabit significantly different climatic niche spaces. Ecological niche models (ENMs) indicate that all varieties’ ranges contracted during the Last Inter Glacial (LIG), and expanded eastward or northward during the Last Glacial Maximum (LGM). Conclusions Pliocene and Plio-Pleistocene climatic fluctuations and vicariance appear to have played key roles in shaping current population structure and historical demography in the A. chinensis complex. The polyploidization process also appears to have played an important role in the historical demography of the complex through improving their adaptability to environmental changes.

Light-triggered therapy is a prospective method to combat implant-associated infection but near-infrared I (NIR-I) light has insufficient penetrating ability in tissues and local hyperthermia induced by the photothermal treatment may destroy surrounding healthy tissues. Herein, a near-infrared II (NIR-II) phototherapy system composed of upconversion elements doped titanium dioxide nanorods (TiO2 NRs)/curcumin (Cur)/hyaluronic acid (HA)/bone morphogenetic protein-2 (BMP-2) is designed for biomedical titanium and demonstrated to overcome the above hurdles simultaneously. Incorporation of F, Yb, and Ho not only improves the photocatalytic ability, but also renders the implants with the upconversion capability, so that the NRs can generate enough reactive oxygen species (ROS) when irradiated by the NIR-II laser. Furthermore, the combined actions of quorum sensing inhibitors, ROS, and physical puncture by NRs eliminate Staphylococcus aureus biofilms on titanium rapidly at a mild temperature of 45 °C by only requiring irradiation with the 1060 nm laser for only 15 min in vitro and in vivo. The presence of Cur mitigates the immune response and BMP-2 improves osteogenic differentiation, thus accelerating new bone formation. This low-temperature NIR-II light-triggered antibacterial platform has large potential in combating deep-tissue infection in clinical applications.

The human immunodeficiency virus type 1 (HIV-1) Gag recognizes viral packaging signal (Psi) specifically via its nucleocapsid (NC) domain, resulting in the encapsidation of two copies of genomic RNA (gRNA) into the viral particle. The NCp7, which is cleaved from Gag during viral maturation, is a nucleic acid chaperone, coating and protecting the gRNA. In this study, an RT-qPCR-based approach was developed to quantitatively compare the Psi-selectivity of Gag and NCp7 in the presence of bacterial or 293T total RNAs. The binding affinity of Gag and NCp7 to the stem-loop (SL) 3 of Psi was also compared using surface plasmon resonance. We found that Gag selected more Psi-RNA than NCp7 from both E. coli BL21 (DE3) and in vitro binding reactions, and Gag bound to SL3-RNA with a higher affinity than NCp7. Moreover, Gag contained two Zn

To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM

The current poor understanding of soluble iron (Fe) yield in atmospheric aerosols leaves two observational facts having not yet been correctly simulated in numerical models: the high Fe solubility in aerosols with low Fe content and, hence, the wide range of observed Fe solubility. Our observation at Qingdao, a coastal city of China, revealed that soluble Fe was produced along with aerosol acidification much more efficiently in fog than under other weather conditions. The median Fe solubility in fog aerosols, 5.81%, was 3.3 times of that in haze aerosols, 5.2 times of that in clear days, and 21.5 times of that in dust aerosols. Involving fog processing in models may reduce the discrepancy in the atmospheric flux of soluble Fe to the ocean between numerical simulations and field observations.

Arsenic is a toxic pollutant commonly found in the environment. Most of the previous studies on arsenic pollution have primarily focused on arsenic contamination in groundwater. In this study, we examine the impact on human health from atmospheric arsenic on the global scale. We first develop an improved global atmospheric arsenic emission inventory and connect it to a global model (Goddard Earth Observing System [GEOS]-Chem). Model evaluation using observational data from a variety of sources shows the model successfully reproduces the spatial distribution of atmospheric arsenic around the world. We found that for 2005, the highest airborne arsenic concentrations were found over Chile and eastern China, with mean values of 8.34 and 5.63 ng/m(3), respectively. By 2015, the average atmospheric arsenic concentration in India (4.57 ng/m(3)) surpassed that in eastern China (4.38 ng/m(3)) due to the fast increase in coal burning in India. Our calculation shows that China has the largest population affected by cancer risk due to atmospheric arsenic inhalation in 2005, which is again surpassed by India in 2015. Based on potential exceedance of health-based limits, we find that the combined effect by including both atmospheric and groundwater arsenic may significantly enhance the risks, due to carcinogenic and noncarcinogenic effects. Therefore, this study clearly implies the necessity in accounting for both atmospheric and groundwater arsenic in future management.

The growth of newly formed particles with diameters from ~ 10 nm to a larger size was investigated in Beijing's urban atmosphere on 10–23 December 2011, 12–27 April 2012 and through June–August 2014. The maximum geometric median diameter (Dpgmax) of newly formed particles in 11/27 new particle formation (NPF) events through June–August exceeded 75 nm, and the grown new particles may contribute to the population of cloud condensation nuclei. In contrast, no apparent growth in new particles with Dpgmax

Atmospheric deposition of iron (Fe) can increase marine primary productivity, consequently affect ocean biogeochemical cycles and climate change. In this study, we develop an adaptor to generate anthropogenic Fe emission inventories for China in 2012 and 2016 via anthropogenic PM2.5 emissions from Multi-resolution Emission Inventory for China (MEIC) using local source-specific mass fractions of Fe in PM2.5. Using the generated emission inventories, we simulated Fe concentrations as well as dry deposition fluxes to China marginal seas using a WRF-CMAQ model during four campaign periods. The simulated Fe concentrations are in good agreement with observations except for those in presence of severe dust-intrusion events (NMB −13% ~ −27%), indicating a reasonably good performance of the generated Fe emissions and leaving the large underestimation of Fe concentrations mainly due to nature dust emissions. Simulated Fe concentrations over China marginal seas are in the range of 62–6.5 × 102 ng m−3, providing 2.0–12.5 μg m−2 d−1 to the seas during the study periods. We also found that inputs of total Fe in PM2.5 to the seas in presence of dust-intrusion events are 3 and 13 times larger than those in presence of haze events or on less polluted days. Due to lower Fe solubility in nature mineral aerosols than in anthropogenic aerosols, dry deposition fluxes of bioavailable Fe on haze days almost double that in dust days. The total anthropogenic emissions of Fe over China in 2012 and 2016 are estimated as 5.5 × 102 Gg and 3.3 × 102 Gg, respectively. Iron and steel industry are the dominant sources of Fe, accounting for 59–63% of the total anthropogenic Fe emissions. Geotropically, stronger emissions per area were distributed in eastern China, e.g., 2.3 to 15.4 ng m−2 s−1 in eastern China versus

Osseointegration is crucial for early fixation as well as for long-term implantation success, hence numerous efforts have been made to tune the surface topography or chemical composition of biomedical implants to improve osseointegration. In this work, various nanostructures, including nanoflocs, nanobundles, nanorods, and nanoleaves, were introduced to the surface of silicon (Si)-incorporated microporous structure to form Si-incorporated micro-nano hierarchical structures on titanium (Ti)-based implants. The osseointegration of the implants were systemically assessed in vivo and in vitro. The in vitro evaluations showed that the nanostructures promoted the protein adsorption, thus modulating the early cellular responses, including the attachment and spreading of osteoblasts and human endothelial cells (HUVECs), and subsequent cell proliferation and differentiation. Furthermore, compared with the single microporous structure, the nanostructures located over the microporous structure protected the Si ions from quick release and allowed the long-term sustained Si-ions release, which further contributed to the proliferation and differentiation of osteoblasts and vascular endothelial growth factor (VEGF) secretion as well as the tube formation of HUVECs. Collectively, the favorable nano-surface structures, especially the nanoleaves structure, and the constant Si-ion release together led to robust osteogenic and angiogenic activities. More importantly, in vivo micro-CT evaluation and histological observations further verified that the Si-incorporated micro-nano hierarchical implant with nanoleaves structure could efficiently promote new bone formation, thus indicating it was an attractive candidate as a next-generation bone-implant material.

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, TiO

Amines reportedly overwhelm ammonia in generating new particles through neutralizing sulfuric acid vapor even with several orders smaller concentrations of amines against ammonia in ambient air, demonstrating an attractive prospect in adjusting concentrations of amines to adjust aerosol number loadings, alleviate air pollution and manipulate aerosol cooling effects. Due to lack of in-situ observations, real competition of amines against ammonia in ambient air to be neutralized by acids remains poorly understood. Here, successful semi-continuous measurements of gaseous amines and ammonia and their particulate partners in marine atmospheres reveal that atmospheric trimethylamine (TMAgas) unable to compete with NH3gas and to form particulate trimethylaminium (TMAH+), but the particulate TMA (TMAparticulate) is detectable and comparable to TMAgas under NH3gas -3. Contradictory to the common knowledge, the preexisting TMAparticulate is largely depleted in strong SO2 plumes with abundant acids and even depleted NH3gas. A two-aerosol-phase transfer concept model is proposed to interpret the new findings, but no single-phase acid-base neutralization reactions can. In contrast, observational evidences confirm that gaseous dimethylamine (DMAgas) plus particulate dimethylaminium (DMAH+) overwhelmingly exist as DMAH+ under atmospheric NH3 (NH3gas) -3 versus DMAgas under NH3gas >1.8 µg m-3, respectively. The neutralization of DMAgas to form DMAH+ is always enhanced in strong SO2 plumes, almost independent on NH3gas. Thermodynamically, DMAgas may act as a competitor in generating secondary particles only under low NH3gas or in SO2 plumes.

Dust deposition can supply nutrients that affect marine phytoplankton, but changing trophic statuses of the surface ocean increase the complexity of interpreting the process. In this study, four onboard incubation experiments amended with various nutrients and dust were performed in the Kuroshio Extension (KE) and Kuroshio–Oyashio transition (TR) of the northwest Pacific (NWP), which are characterised by lower and higher trophic statuses, respectively. According to the nutrient-addition experiments, phytoplankton were limited by nitrogen (N) in the KE, and limited by iron (Fe) or co-limited by Fe and phosphorus (P) in the TR. Dust additions supplied a considerable amount of N and Fe but negligible amount of P to stimulate phytoplankton growth, as indicated by chlorophyll a (Chl a) concentration. In the KE incubations, dust additions enhanced the shift of phytoplankton size structure towards larger cells from dominantly pico-sized (0.2–2 μm) Chl a to comparable contributions from each size class (i.e. pico-, nano-: 2–20 μm, micro-: >20 μm). On the basis of the large shift of size structure towards nano- or micro-phytoplankton in the unamended control treatments in the TR, dust additions furtherly promoted the shift towards micro-phytoplankton becoming the dominant contributor to the total Chl a. The collective analysis of the data from experiments in both regions revealed that, the extent of phytoplankton growth stimulation and the shift towards larger cells were enhanced gradually with increasing amounts of nutrient uptake (including N, P, and silicon). The nutrient uptake ratios of phytoplankton converged towards the Redfield ratio in comparison to the wider range of nutrient ratios in the dust-amended seawater. This study suggested consistencies in the dynamic of phytoplankton growth, shift of size structure, and nutrient uptake following dust additions in the KE and TR, although the trophic status and limiting nutrient varied between these two regions.

In this study, a cruise campaign was conducted over China marginal seas to measure concentrations of condensation nuclei (Ncn), cloud condensation nuclei (Nccn) and other pollutants during DOY 110 to DOY 135 of 2018. With exhaustedly excluded self-ship emission signals, the mean values of Nccn during the cruise campaign slightly increased from 3.2 ± 1.1 × 103 cm−3 (mean ± standard) at supersaturation (SS) of 0.2 % to 3.9 ± 1.4 × 103 cm−3 at SS of 1.0 %, and the mean value for Ncn was 8.1 ± 4.4 × 103 cm−3. Data analysis showed that marine traffic emissions apparently yielded a large contribution to the increase of Ncn in daytime, especially in marine atmospheres over their heavily travelled sea zones; however, the fresh sources had no clear contribution to the increase of Nccn. This finding was supported by the quantitative relations between Ncn and Nccn at SS = 0.2–1.0 % against mixing ratios of SO2 in self-ship emission plumes, i.e., 1 ppb increase in SO2 corresponds to 1.4 × 104 cm−3 increase in Ncn, but only 30–170 cm−3 increase in Nccn possibly because of abundant organics in the aerosols. The smooth growth of marine traffic derived particles can be observed, reflecting aerosol aging. The estimated hygroscopicity parameter (κ) values were generally as high as 0.46–0.55 under the dominant onshore winds, suggesting inorganic ammonium aerosols likely acting as the major contributor to Nccn through aerosol aging processes largely decomposed organics. Moreover, the influences of the transported new particles from the continent on Ncn and Nccn in the marine atmosphere were also investigated.

In this study, the spatial pattern and temporal evolution of PM2.5 over North China Plain (NCP) and Northeast China (NEC) during 2014-2018 was investigated. The annual mean PM2.5 shows clear decreasing trends over time, but the seasonal mean PM2.5 as well as the seasonal total duration and frequency of haze days shows large inter-annual fluctuation. Based on the atmospheric stagnation index (ASI), this study examined the correlation between ASI and haze events over NCP and NEC. Detailed analysis indicates that location dependency exists of ASI in the capability of capturing the haze events, and the ability is limited in NCP. Therefore, we first propose two alternative methods in defining the ASI to either account for the lag effect or enlarge the threshold value of wind speed at 500 hPa. The new methods can improve the ability of ASI to explain the haze events over NEC, though marginal improvement was achieved in NCP. Furthermore, this study constructed the equation based on the boundary layer height and wind speed at 10-meter, apparently improving the ability in haze capture rate (HCR), a ratio of haze days during the stagnation to the total haze days. Based on a multi-model ensemble analyses under Representative Concentration Pathway (RCP) 8.5, we found that by the end of this century, climate change may lead to increases in both the duration and frequency of wintertime stagnation events over NCP. In contrast, the models predict a decrease in stagnant events and the total duration of stagnation in winter over NEC.

A fast mobility particle sizer operating at a one-second time resolution was used to measure aerosol particle number size distribution (5.6-560 nm) in marine conditions over the South China Sea (SCS) from 29 March to 2 May 2017 and in the tropic zone of the Northwest Pacific Ocean (NWPO) from 10 to 29 October 2018. The clean background number concentration of nucleation mode atmospheric particles (30 nm) was approximately 0.6 × 10

After prosthesis replacement for the treatment of bone tumors, incomplete removal of tumor cells is the main challenge. Moreover, combating implant-associated infection and simultaneously promoting osseointegration are highly demanded for orthopedic implants and therefore, a multifunctional coating that produces tumor therapeutic effects, antibacterial activity, and osteogenesis at the same time is of clinical significance. Herein, a phototherapy platform composed of rare-earth elements - doped titanium dioxide nano-shovel/quercetin/L-arginine (TiO2@UCN/Qr/LA) on titanium bone implant is fabricated. The stable nano-shovel structure prepared by a hydrothermal method improves the photothermal conversion ability of titanium. Incorporation of Yb and Er enhances the upconversion capability, thereby facilitating generation of reactive oxygen species (ROS) during exposure to near-infrared II (NIR-II) light. Furthermore, under the action of ROS, L-arginine is catalyzed to release nitric oxide (NO) free radicals. In vitro and in vivo experiments indicate that the combined actions of ROS, quercetin, and NO not only inhibit bone tumor growth at a temperature of 48 ℃, but also eliminate Staphylococcus aureus biofilms on the Ti implants at a mild temperature of 45 ℃ upon illumination with a 1,060 nm laser. Moreover, TiO2@UCN/Qr/LA promotes angiogenesis and osteogenic differentiation, reduces inflammation, and accelerates formation of new bone tissues.