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The preparation of pH-responsive nanocontainers by typical silane modification of the mesoporous silica nanoparticle (MSN) surface is usually high-cost, complex, and time-consuming, which remains a great challenge for effective corrosion protection of magnesium alloy. Here, a new strategy to construct pH-responsive nanocontainers (MSN-MBT@LDH) is demonstrated. The nanocontainers consist of corrosion inhibitor (2-mercaptobenzothiazole, MBT) loaded MSN core and layered double hydroxide (LDH) nanosheet shell serving as gatekeepers. The successful loading of MBT and encapsulation by LDH nanosheets were confirmed by a series of characterization such as scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS) and N2 adsorption/desorption isotherms. The pH-responsive feature of the nanocontainers was demonstrated by determination of the MBT concentration in buffer solutions with different pH values. A smart corrosion protection system on Mg alloy is obtained by incorporating the synthesized nanocontainers into a self-assembled nanophase particle (SNAP) coating. The electrochemical tests and visual observations show that the hybrid coating has the best barrier properties and robustness in corrosion protection in NaCl corrosive solutions in comparison with the control coatings. The present method simplifies the synthesis processes of nanocontainers and eliminates the potential detrimental effect of excess gatekeepers on the coating. The findings provide new insights into the preparation of scalable nanocontainers. The self-healing coatings are expected to have widespread applications for corrosion protection of Mg alloy and other metals.

The adverse impacts of AFB1 on gut-microbiota dependent metabolism in F344 rats were assessed via ultra-high performance liquid chromatography (UHPLC)-profiling and UHPLC-mass spectrometry (MS) metabolomic analyses. UHPLC-profiling analysis found 1100 raw peaks from the fecal samples collected at week 4, of which 335 peaks showed peak shape qualified for quantitation. A total of 24, 40 and 71 peaks were significantly decreased (>2-fold, p

Fumonisin B1 (FB1) is a neurodegenerative mycotoxin synthesized by Fusarium spp., but the potential neurobehavioral toxicity effects in organisms have not been characterized clearly. Caenorhabditis elegans (C. elegans) has emerged as a promising model organism for neurotoxicological studies due to characteristics such as well-functioning nervous system and rich behavioral phenotypes. To investigate whether FB1 has neurobehavioral toxicity effects on C. elegans, the motor behavior, neuronal structure, neurotransmitter content, and gene expression related with neurotransmission of C. elegans were determined after exposed to 20-200 μg/mL FB1 for 24 h and 48 h, respectively. Results showed that FB1 caused behavioral defects, including body bends, head thrashes, crawling distance, mean speed, mean amplitude, mean wavelength, foraging behavior, and chemotaxis learning ability in a dose-, and time-dependent manner. In addition, when C. elegans was exposed to FB1 at a concentration of 200 μg/mL for 24 h and above 100 μg/mL for 48 h, the GABAergic and serotonergic neurons were damaged, but no effect on dopaminergic, glutamatergic, and cholinergic neurons. The relative content of GABA and serotonin decreased significantly. Furthermore, abnormal expression of mRNA levels associated with GABA and serotonin were found in nematodes treated with FB1, such as unc-30, unc-47, unc-49, exp-1, mod-5, cat-1, and tph-1. The neurobehavioral toxicity effect of FB1 may be mediated by abnormal neurotransmission of GABA and serotonin. This study provides useful information for understanding the neurotoxicity of FB1.

To understand the impact of pollution control measures on the ambient fine particle (PM2.5) in Nanjing, two sampling campaigns before and after the release of pollution control measures (BPCM: Jan.–Nov. 2014 and APCM: Nov. 2015–Jul. 2016) were conducted. Chemical compositions, sources, regional transport, and potential health risks of PM2.5 for the two distinguishable periods were compared. Results showed that the annual averaged PM2.5 concentrations in Nanjing decreased by 12.4% from BPCM (100 ± 54.3 μg m−3) to APCM (87.6 ± 56.4 μg m−3). Chemical mass closure showed that secondary inorganic aerosols (SIA) contributed most to the PM2.5 mass (50.7% and 47.1% for BPCM and APCM), followed by carbonaceous components (30.8% and 33.8%) for both the two periods. Positive matrix factorization (PMF) modeling showed that the annual average mass contributions of biomass burning (BB), industrial process (IP), vehicle emission (VE), and secondary inorganic aerosol (SIA) decreased by 5.60%, 60.9%, 22.0% and 35.8%, respectively, from BPCM to APCM, whereas the contribution of coal combustion (CC) increased by 94.1% due to the significant increase in winter. Combined with the PMF, Hybrid Single Particle Lagrange Trajectory (HYSPLIT), potential source contribution function (PSCF), concentration-weighted trajectory (CWT), and cluster analysis results, the regional transport of the five identified sources in different periods were obtained. The regional transport of BB, IP, VE and SIA decreased by 50.9%, 82.9%, 10.5%, and 23.4%, respectively from BPCM to APCM, while the CC increased by 131% from BPCM to APCM. Health risk assessment showed that the non-carcinogenic risk and carcinogenic risk of PM2.5-bound heavy metals decreased by 50.0% and 58.3%, respectively. These results indicated that the PM2.5 pollution control measures were effective in Nanjing, for both reducing the mass concentrations and health risks of PM2.5. Further attention should be paid to the reduction of the secondary inorganic aerosols and industrial process, due to their high contribution to PM2.5 mass and health risks. This study also highlighted the impact of regional transport of coal combustion emission from north China on south cities, which should be controlled more strictly especially in winter of China.

The Pr3+-doped NaY(MoO4)2 crystals were prepared by the hydrothermal method, and sodium citrate was used as the chelating agent. The structure, morphology, and relationship between optical properties and temperature were measured. The X-ray diffraction results showed that the crystal structure is body-centered tetragonal, and the addition of sodium citrate did not distinctly alter the phosphor structure. From 298 to 483 K, under a 270 nm excitation, 1D2-3H4, 3P0-3H4, and 3P0-3F2 transitions have different temperature dependencies, and two groups of fluorescence intensity ratio (1D2-3H4 and 3P0-3H4, 1D2-3H4 and 3P0-3F2) can be defined to characterize the temperature. The morphological characteristics of the sample were obtained by the detection of field emission scanning electron microscope. The experiment showed that the relative sensitivity changed as a function of the sample morphology. The maximum relative sensitivity of the synthesized phosphors (Cit3−/Re3+ = 2) reached 1.00% K−1 at 313 K, and the relative sensitivity remained near the maximum value when the temperature was close to human body temperature (308–315 K). The Pr3+-doped NaY(MoO4)2 phosphor is a high-performance material that can be employed for refined calibration and temperature measurements according to the two-group schema defined by fluorescence intensity ratio. Thus, it show utilization potentiality in self-calibration optical thermometers and temperature measurements including humans and special environment.

In this study, the possible molecular mechanisms of zearalenone (ZEA)-induced reproductive and developmental toxic effects in Caenorhabditis elegans (C. elegans) were investigated. Differential gene expression profiles were identified, and 171, 245, and 3149 genes were down- or up-regulated (>2.0 fold) in 10, 20, and 40 μg/ml ZEA treated groups, respectively, as compared to untreated controls. Pathway specific mapping showed that the major differentially expressed genes were collagen synthetic pathways regulating genes, col-121 and dpy-17. Real-time PCR reconfirmation of key genes, related to cuticle collagen synthetic pathway, found dramatic changes in the expression of the genes dpy-31, sqt-3, col-121, and dpy-17 following exposure to ZEA (40 μg/ml), which indicated the significance of these genes in ZEA-induced toxicity. Cuticle collagen plays many key roles in the development and reproduction of C. elegans. The hypersensitive responses in transgenic and mutant worms also confirmed the roles of these genes in lethality and reproductive response to ZEA exposure, which indicates that ZEA blocked the normal collagen processing and cuticle formation. Taken together, our results demonstrate that disruption of the collagen biosynthetic pathway might be a key mechanism in ZEA-induced reproductive and developmental toxic effects in C. elegans.

Our recent metagenomics analysis has uncovered remarkable modifying effects of green tea polyphenols (GTP) on gut-microbiota community structure and energy conversion related gene orthologs in rats. How these genomic changes could further influence host health is still unclear. In this work, the alterations of gut-microbiota dependent metabolites were studied in the GTP-treated rats. Six groups of female SD rats (n=12/group) were administered drinking water containing 0%, 0.5%, and 1.5% GTP (wt/vol). Their gut contents were collected at 3 and 6 months and were analyzed via high performance liquid chromatography (HPLC) and gas chromatography (GC)-mass spectrometry (MS). GC-MS based metabolomics analysis captured 2668 feature, and 57 metabolites were imputatively from top 200 differential features identified via NIST fragmentation database. A group of key metabolites were quantitated using standard calibration methods. Compared with control, the elevated components in the GTP-treated groups include niacin (8.61-fold), 3-phenyllactic acid (2.20-fold), galactose (3.13-fold), mannose (2.05-fold), pentadecanoic acid (2.15-fold), lactic acid (2.70-fold), and proline (2.15-fold); the reduced components include cholesterol (0.29-fold), cholic acid (0.62-fold), deoxycholic acid (0.41-fold), trehalose (0.14-fold), glucose (0.46-fold), fructose (0.12-fold), and alanine (0.61-fold). These results were in line with the genomic alterations of gut-microbiome previously discovered by metagenomics analysis. The alterations of these metabolites suggested the reduction of calorific carbohydrates, elevation of vitamin production, decreases of bile constituents, and modified metabolic pattern of amino acids in the GTP-treated animals. Changes in gut-microbiota associated metabolism may be a major contributor to the anti-obesity function of GTP.

Populations consuming aflatoxin (AF) and fumonisin (FN)-contaminated foods may be at increased risk for hepatocellular carcinoma (HCC) and developmental disorders; consequently, development of intervention strategies to reduce AF/FN-induced liver disease and adverse health effects in humans could be very useful. Calcium montmorillonite clay (NovaSil) has been shown to absorb AF in vitro, in multiple animal models, as well as in human studies. In the present study, we aimed to evaluate whether uniform particle size NovaSil (UPSN) possessed an ability to modulate the co-carcinogenic potentials of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) in F344 rats. Sequential treatment of FB1 following AFB1 synergistically induces preneoplastic alterations as well as liver damage, indicating that AFB1 acts as an initiator while FB1 as a promoter in the carcinogenesis model, confirming findings from previous studies. The enterosorbent agent UPSN clay at dose of up to 0.5% in diet was shown to be effective in modulating the toxicity and carcinogenicity of co-exposure to AFB1 and FB1, as demonstrated by significant reduction in number and size of hepatic GST-P+ foci, in alterations indicative of liver toxicity, and in levels of AFB1 and FB1 biomarkers.

Nanotechnology has led to the development of new nanomaterials with unique properties and a wide variety of applications. In the present study, we focused on the cellular uptake of a group of nanoparticles with a single metal core by pancreatic cancer cells, which has been studied by Yap et al. (Rsc Advances, 2012, 2 (2):8489-8496) using classification models. In this work, the development of a further Quantitative Nanostructure-Activity Relationship (QNAR) model was performed by linear multiple linear regression (MLR) and nonlinear artificial neural network (ANN) techniques to accurately predict the cellular uptake values of these compounds by dividing them into three groups. Judging from the attained statistical results, our derived QNAR models have an acceptable overall accuracy and robustness, as well as good predictivity on the external data sets. Moreover, the results of this study provide some insights on how engineered nanomaterial features influence cellular responses and thereby outline possible approaches for developing and applying predictive computational models for biological responses caused by exposure to nanomaterials.

Revealing the diversity and composition of soil microbial communities (particularly bacterial communities) at aggregate scales exhibits a huge significance for maintaining the sustainable utilization of soil resources in the tea garden ecosystems. This study focused on the analysis of the bacterial community structure (based on the high-throughput sequencing measurement) in soil aggregates (at the 0–20 cm depth) collected from tea gardens at different ages (8, 17, 25, and 43 years) in southern Guangxi, China. Soil aggregates were classified into coarse (>2 mm), medium (2–1 mm), and fine (1–0.25 mm) macro-aggregates, as well as micro-aggregates (

Soil aggregation as one of the key processes can maintain soil quality. Revealing the relationships of soil aggregate stability with the relevant bio-chemical parameters could provide valuable guidance to maintain soil quality in the Chinese fir plantations. In this study, soil samples (0–20 cm and 20–40 cm depths) were collected from Chinese fir plantations with various stand ages (3 years, 9 years, 17 years, and 26 years) in Guangxi, China. Soil aggregates with four different sizes were obtained through the optimal moisture sieving method, including the >2 mm, 2-1 mm, 1–0.25 mm, and

Leaf stoichiometric pattern and its potential determinants are of great significance in the modeling nutrient cycling, detecting ecosystem stability and predicting the response of ecosystem to global changes. To reveal the stoichiometric characteristic of Pinus bungeana, we analyzed the needle nitrogen (N) and phosphorous (P) concentrations of 76 needle samples from 15 sampling sites throughout the country, and took the local geographical and climatic variables into consideration. The generalized linear mixed model (GLMM) and principal component analysis (PCA) were used to explore the effects of environmental factors on needle stoichiometry. This study revealed that both the concentrations and ratio of N, P content showed significant differences in needles of P. bungeana among different sampling sites. The needle N, P concentrations and N: P ratio showed quadratic curve correlation with climatic factors. The PCA indicated that all variables can be explained by three principal components, namely, temperature, N and P, which were very important factors affecting the geographical distribution of P. bungeana. Among the three components, N is most crucial factor limiting the growth and metabolism of P. bungeana. In summary, our study will help to elucidate the patterns of needle N and P concentrations in needles of P. bungeana, thus revealing the causes and driving forces for its natural region.

Fusarium graminearum is the main worldwide causal agent of Fusarium head blight grain disease. The production of mycotoxin caused by Fusarium head blight epidemics of wheat affects the flour and malt products, which results in heavy economic losses to farmers. In this paper, an inactivation procedure for F. graminearum F7875 spores was tested and found to follow a first-order kinetic model. We characterized the inactivation of F7875 by aqueous chlorine dioxide (ClO 2 ) under different concentrations (5–15 mg L −1 ). The results suggest that aqueous ClO 2 significantly enhanced inactivation of F7875 at high concentration (15 mg L −1 ) compared to lower concentration of 5 and 10 mg L −1 . The time required for a five-log reduction of F7875 spores was calculated based on the established models. Observed by scanning electron microscope, the ClO 2 destroys the structure of the outer coats of F7875, the surface of F7875's hyphal appeared smooth prior to treatment, but after treatment with 30 mg L −1 aqueous ClO 2 , it appeared rugged and wrinkled. In conclusion, our study shows that treatment with aqueous ClO 2 is an effective, fast, and safe method to control F. graminearum in grain production.

The recent development of selective oxidation of aromatic sulfides with molecular oxygen was highlighted. The sulfoxides and sulfones could be obtained by simply switching the reaction media, i.e., bis(2-butoxyethyl)ether (BBE) or poly(ethylene glycol)dimethyl ether (PEGDME). The application of the high-boiling-point polyether as an initiator and green media can eliminate the need of large quantities of additives and volatile solvents. This strategy represents an economic and eco-friendly method that could find potential applications.

Long non-coding RNAs (lncRNAs) contribute to various biological processes, including sexual development. As a member of the DMRT family, dmrt2 plays a very important role in sex determination and differentiation. In this study, we cloned and characterized the lncRNA DMRT2-AS (referred to as dmrt2 antisense) associated with dmrt2 from the gonads of the Chinese tongue sole (Cynoglossus semilaevis). The full-length cDNA of DMRT2-AS was 537 bp. Based on a sequence alignment, DMRT2-AS overlapped with dmrt2 in reverse on exon 4 and intron 3, with a region of overlap of 221 bp on exon 4. RT-qPCR showed that DMRT2-AS was highly expressed in the testis of Chinese tongue sole. In addition, the expression of DMRT2-AS increased continuously during male gonadal development. In vitro experiments and bioinformatics predictions showed that DMRT2-AS promoted the expression of dmrt2 at the transcriptional level. These results suggest that DMRT2-AS acts as a transcriptional regulator of dmrt2 and plays an important role in the gonadal differentiation of male.

We numerically studied the spin-dependent optical torque on a 2D chiral plasmonic nanomotor excited by circularly polarized lights. An interesting phenomenon of so-called negative optical torque is demonstrated on condition that the scattering optical torque is opposite to and larger than absorption optical torque under a plasmonic resonance of dipolar mode. Moreover, the calculated optical torque, exerted on the nanomotor, is monotonically tunable depending on the ellipticity of light. It is theoretically estimated that the spin-dependent rotation frequency can be modulated from about 3.56 kHz to 8.91 kHz under incident intensity of 1 mW ∕ μ m 2 . Our results demonstrate a counterintuitive rotation phenomenon on light-driven 2D chiral nanomotor, and open a manipulation avenue to control optically-induced torque via absorption and/or scattering of light by 2D chiral plasmonic meta-atom.

Accurately mapping of regional-scale evapotranspiration (ET) from the croplands using remote sensing is currently challenged by limited spatial information on crop and field management to properly characterize the biophysical constraints on ET. A multi-model ensemble can potentially address this challenge, however, conventional ensemble models using the simple average (MEAN) or Bayesian Model Average (BMA) assign a fixed weight to each model and may not fully utilize the strengths of individual models. To this end, we developed four ensemble ET Models (EEMs) that use different machine learning (ML) classifiers, namely K-nearest neighbors, random forest, support vector machine, and multi-layer perception neural network (MLP), to assign varying weights to assemble six physically-driven remote sensing-based ET models. These ML-based EEMs were compared against the six individual ET models and two conventional ensemble methods (MEAN and BMA) using latent heat fluxes (λE) observations from 47 cropland eddy covariance flux sites covering diverse environments across the globe. Results suggested that while MEAN and BMA can reduce some uncertainties in the individual models, ML-based EEMs can better integrate the capabilities of multiple biophysical constraints on ET used across the individual models. The four ML-based EEMs yielded daily λE for training, validation, and testing datasets with the coefficient of determination (R2) and root mean squared error (RMSE) within 0.75 – 0.83 and 18 – 21 W m−2, respectively, among which the MLP algorithm was found to be the most efficient with respect to accuracies and costs. These performance metrics were much better than those from the conventional ensemble models (R2 = 0.69 – 0.71, RMSE = 23 – 25 W m−2) and six individual ET models (R2 = 0.53 – 0.69, RMSE = 26 – 35 W m−2). Results suggested that ML-based EEMs perform much better than the conventional approaches and hence can be viable tools for mapping cropland ET across a wide environmental gradient.

Adding sodium citric as chelator, NaY(MoO4)2: Pr3+, Tb3+ phosphors were prepared by hydrothermal method. XRD (X-ray diffraction) is employed to confirm the microscopic arrangement of the samples, and the test data show that phosphors are body – centered tetragonal structure. The FE-SEM (Field Emission Scanning Electron Microscope) results indicate that the addition of sodium citrate has a certain effect on the morphology of the samples. It was found from the measured temperature-dependent emission spectrum that Pr3+ and Tb3+ has different quenching trends, and temperature can be characterized by FIR (fluorescence intensity ratio) of Pr3+ ion and Tb3+ ion. Moreover, the experimental results display that with the rise of the molar ratio of Cit3−/Re3+, the sensitivity of phosphors gradually decreases, but the relative sensitivity gradually increases. The relative sensitivity of obtained samples has a higher value of 3.00% K−1 (Cit3−/Re3+ = 2). From the CIE chromaticity coordinates, it displays that the luminous color of phosphors changed continuously with the change of temperature.

Dried blood spots (DBS) were proposed as potentially viable method for exposure assessment of environmental toxicants in infant and young children. For this study, we validated an experimental protocol to quantify AFB1-lysine adduct in DBS samples of AFB1-treated F344 rats, as well as samples from human field study. Significant dose-response relationships in AFB1-lysine adduct formation were found in DBS samples of rats treated with single- and repeated-dose AFB1. AFB1-lysine levels in DBS samples were highly correlated with corresponding serum sample levels. The Person coefficients were 0.997 for the single-dose exposure, and 0.996 for the repeated-dose exposure. Levels of AFB1-lysine adduct had also good agreement between DBS and serum samples as shown by Bland-Altman plot analysis. For human field study samples (n = 36), a Pearson correlation coefficient of 0.784 was found between AFB1-lysine adduct levels of DBS and corresponding serum samples. Bland-Altman plots showed the distribution of the log differences between DBS and serum AFB1-lysine levels are within 95% confidence intervals. These results showed AFB1-lysine adduct levels in DBS cards and serum samples from animals and human samples are comparable, and the DBS technique and analytical protocol is a good means to assess AFB1 exposure in infant and children populations.

Deoxynivalenol (DON) is a secondary metabolite produced by Fusarium graminearum in grains, food and contaminated feed, which can lead to many adverse health effects to humans and livestock. The degradation of DON in different contaminated grains oxidated by saturated aqueous ozone (80 mg L−1) was monitored by ultra-high-performance liquid chromatography, tandem-quadrupole-detection mass spectrometry (UPLC–TQD-MS). Results suggest that ozone has a significant effect on DON reduction in solution. When 80 mg L−1 gaseous ozone was used to treat 10 mg L−1 of DON solution, the degradation rate of DON reached 83% within 7 min, while the respective detoxification rates of contaminated wheat, corn and bran by saturated aqueous ozone (80 mg L−1) were 74.86%, 70.65% and 76.21 in 10 min. Ozone at 80 mg L−1 was applied on various DON solution concentrations at 1 mg L−1, 10 mg L−1 and 20 mg L−1 in ultra-pure water. In this paper, the degradation procedure for DON is calculated and described by a first-order kinetic equation. At lower levels (20 mg L−1) of aqueous ozone, intermediate degradation products were observed by ultra-ne quickly and effectively degrades DON and toxicity in various contaminated grains in a matter of minutes. Therefore, ozonation is projected to be an effective, fast, and safe method for DON degradation.

Understanding how engineered nanoparticles (ENPs) interact with natural organic acids is important to ecological risk assessment of ENPs, but this interaction remains poorly studied. Here, we investigate the dispersion stability, ion release, and toxicity of yttrium oxide nanoparticles (nY2O3) suspensions after exposure to two low molecular weight natural organic acids (LOAs), namely benzoic acid and gallic acid. We find that in the presence of LOAs the nY2O3 suspensions become more stable with surface zeta potential more positive or negative, accompanied by small agglomerated size. LOA interaction with nY2O3 is shown to promote the release of dissolved yttrium from the nanoparticles, depending on the concentrations of LOAs. Toxic effects of the nY2O3 suspensions incubated with LOAs on Scenedesmus obliquus as a function of their mixture levels show three types of signs: stimulation, inhibition, and alleviation. The mechanism of the effects of LOAs on the nY2O3 toxicity may be mainly associated with the degree of agglomeration, particle-induced oxidative stress, and dissolved yttrium. Our results stressed the importance of LOA impacts on the fate and toxicity of ENPs in the aquatic environment.

The decontamination of Aflatoxin B1 (AFB1) by immobilized cells of a new mutant strain, prepared on a base of HSCAS (hydrated sodium calcium aluminosilicate), was studied. Novel strains were induced by UV irradiation, from which 50 were screened according to their degradation efficacy on AFB1, compared with the wild strain (FS-Z1). The FS-UV1 strain exhibited highest degradation efficacy, which was confirmed by 18SrDNA to be Aspergillus niger. The results indicate that both immobilized cells and this mutant strain which are incubated for 48 h at 30 °C, would considerably remediate AFB1 in nutrient broth culture, by 95.32% and 82.43%, respectively. By the application of samples of contaminated cottonseed meal, with results of 93.46%∼96.82%, the degradation rate was also validated. The results of Ames test indicate the mutagenic activity of treated AFB1 is greatly abated, with treated controls. The Application of LC-q-TOFMS (liquid-chromatography, quadrupole, time-of-flight mass spectrometry) deduces the structure and molecular formulas of the degradation products. In the vivo study, the damages of photomicrographic evidence are decreased in kidney and liver and the serum biochemical parameters is improved, in response to preventative treatment with immobilized cells. This is the application of HSCAS-prepared, immobilized A. niger cells to degrade AFB1 of contaminated samples. The investigation in this paper offers a novel path for economical, time-saving biodegradation of AFB1 in foods and feeds.

Air quality change is generally driven by two factors: pollutant emissions and meteorology, which are difficult to distinguish via observations. To identify the contribution of meteorological factor to air quality change, an aerosol simulation from 1995 to 2004 with the global air quality model GEM-AQ/EC was designed without year-to-year changes in the anthropogenic aerosol (including sulfate and organic and black carbon) emissions over the 10-year span. To assess the impact of interannual variations of East Asian monsoon (EAM) on air quality change in China, this modeling study focused on the region of central-eastern China (CEC), a typical East Asian monsoon (EAM) region with high anthropogenic aerosol emissions. The simulation analysis showed that the interannual variability in surface aerosols over CEC was driven by fluctuation in meteorological factors associated with EAM changes. Large amplitudes of interannual variability in surface aerosol concentrations reaching 20–30% relative to the 10-year averages were found over southern CEC in summer and over northern CEC in winter. The weakened near-surface winds of EAMs in both summer and winter were significantly correlated with aerosol increases over most areas of CEC. The summer and winter monsoon changes enhance the surface aerosol concentrations with increasing trend rates exceeding 30% and 40% over the southern and northern CEC region, respectively, during the 10 years. The composite analyses of aerosol concentrations in weak and strong monsoon years revealed that positive anomalies in surface aerosol concentrations during weak summer monsoon years were centered over the vast CEC region from the North China Plain to the Sichuan Basin, and the anomaly pattern with “northern higher” and “southern lower” surface aerosol levels was distributed over CEC in weak winter monsoon years. Aerosol washout by summer monsoon rainfall exerted an impact on CEC aerosol distribution in summer; aerosol dry depositions in connection with atmospheric boundary layer conditions resulted in wintertime aerosol variations over CEC. Climate change with regard to EAMs could modulate the interannual variations in aerosols and air quality over CEC by changing near-surface winds, precipitation and atmospheric boundary layer.

Hygroscopic properties of aerosol particles are important for determining aerosol size distributions, and thus determining scattering and absorption coefficients at ambient atmospheric conditions. In this study, hygroscopic properties of aerosol particles at an urban site in Guangzhou, China, were measured using a Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA) system during the winter and the summer. The results show that the urban aerosols were composed of more-hygroscopic, less-hygroscopic and non-hygroscopic particles. For less-hygroscopic particles of 40–200 nm in diameter, the hygroscopic parameter κ LH was around 0.15. For more-hygroscopic particles, the κ MH was from 0.290 to 0.339 with a particle size from 40 to 200 nm. For non-hygroscopic particles, the κ NH was about 0.015. It was found that the number fraction of less-hygroscopic particles (NF LH ) was correlated with the atmospheric oxidation which can be presented by OC/EC. This paper attributed the larger NF LH in winter to the higher value of OC/EC (3.0). Such conditions may lead to more formation of less-hygroscopic particles. Backward trajectories cluster analysis shows that there is a certain link between air mass origin and aerosol hygroscopicity, but it seems to be independent of the level of pollution. The difference of NF NH indicates that the mixing state of aerosol particles can also be affected by air mass origin. Diurnal variations in aerosol hygroscopic parameters in both seasons show that during daytime, aerosol particles tend to have a low degree of external mixing or quasi-internal mixing, resulting in a higher NF MH and a larger κ mean ; during nighttime and early mornings, they tend to be mixed externally, resulting in a lower NF MH and a smaller κ mean . This can be attributed to atmospheric aging effect and evolution of mixing layer height and implies that soot (non-hygroscopic) particles present to a large extent as internal mixtures by the time they leave the urban environment. Hence, only assuming a constant mixing state of soot particles, such as pure external or internal for the regional climate model and air quality model is still not realistic and may lead to uncertainties for the Pearl River Delta (PRD) region which is one of the three major economic regions in China. Comparing the diurnal variation of NF NH in both seasons, it seems that such a diurnal cycle was mainly related to the differences in evolution of mixing layer between two seasons. Such quantitative hygroscopic properties of sub-micro particles are essential in assessing their impact on weather–climate effect and atmospheric visibility.

Nickel is the most prevailing metal allergen with the highest sensitization rate among the “TOP 25” contact allergens and can affect about 15% of the human population. It is an essential trace metal in plants, animals, and humans. However, the environmental levels of nickel are considerably higher than what is needed for human life. Exposure to high levels of nickel can lead to skin allergies, lung fibrosis, and carcinogenesis. Few existing studies have closely examined the toxicity of nickel, let alone investigated the effective detoxification pathways. Here, we developed a high-throughput screening platform to comprehensively evaluate the nickel toxicity in wild-type C. elegans and explore the underlying detoxification mechanisms in transgenic nematodes. We demonstrated that nickel exerted multiple toxic effects on growth, brood size, feeding, and locomotion in C. elegans. Of which, brood size is the most sensitive endpoint. Nickel was found to first bind to phytochelatin (PC) after entering the worms’ body and this PC-Ni complex was further transported by the ABC transporter, CeHMT-1, into the coelomocytes for further detoxification. Our study also demonstrated that the high-throughput screening platform is a promising system for evaluation and investigation of the ecological risks of heavy metals.

Green tea polyphenols (GTPs) were found to boost mammal energy conversion by modulating gut-microbial community structure, gene orthologs and metabolic pathways. Here we examined the metabolites present in the gut-microbiota-dependent mitochondrial tricarboxylic acid (TCA) cycle and urea cycle using hydrophilic interaction liquid chromatography (HILIC)-heated electrospray ionization (HESI)-tandem liquid chromatogram mass spectrometry (LC-MS). Six groups (n=12) of Sprague-Dawley rats (6-mo, ~250 g) were administered with water containing 0%, 0.5%, and 1.5% GTPs (wt/vol or g/dL). Gut-content samples were collected at 3- and 6-mo. Untargeted metabolomics detected 2177 features, with 91 features demonstrating significant dose- and time-dependencies on the GTPs treatment. Targeted metabolomics analysis revealed remarkable changes of 39 metabolites in the mitochondrial TCA cycle and urea cycle, including argininosuccunic acid (0.9-fold vs control), dihydrouracil (1.14-fold vs control), fumaric acid (1.19-fold vs control), malic acid (2.17-fold vs control), citrulline (1.86-fold vs control), and succinic acid (0.4-fold vs control). The untargeted metabolomics data were mined using bioinformatics approaches, such as analysis of variance-simultaneous component analysis (ASCA), enrichment pathway analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping analysis. The results of 16S rRNA survey, metagenomics analysis, and metabolomics analysis were extrapolated and integrated using databases of Integrated Microbial Genomes and Microbiomes (IMG/M) and KEGG. Our analysis demonstrates that GTPs enhance energy conversion by boosting mitochondrial TCA cycle and urea cycle of gut-microbiota in rats. This metabolic modulation is achieved by enriching many gene orthologs, following the increase of beneficial microbials in families C. Ruminococcaceae, C. Lachnospiraceae and B. Bacteroidaceae.

In tumors, vascular endothelial growth factor (VEGF) contributes to angiogenesis, vascular permeability, and tumorigenesis. In our previous study, we found that α-solanine, which is widespread in solanaceae, has a strong anti-cancer effect under normoxia. However, it is unknown whether α-solanine has a similar effect under hypoxia. We used cobalt chloride (CoCl2) to mimic hypoxia in vitro. HIF-1α, which is almost undetectable under normoxia, was significantly increased. Simultaneously, another regulator of VEGF, STAT3, was also significantly activated by CoCl2. We utilized α-solanine in co-culture with CoCl2. α-solanine decreased the expression of VEGF and loss of E-cadherin. α-solanine also suppressed the activation of phospho-ERK1/2 (p-ERK1/2), HIF-1α, and STAT3 signaling. The results provide new evidence that α-solanine has a strong anti-cancer effect via the ERK1/2-HIF-1α and STAT3 signaling pathways and suggest that it may be a potential new drug.

To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%).

To investigate the composition, sources and evolution processes of submicron aerosol during wintertime, a field experiment was conducted during December 1–31, 2013 in urban Nanjing, a megacity in Yangtze River Delta of China. Non-refractory submicron aerosol (NR-PM1) species were measured with an Aerodyne Aerosol Chemical Speciation Monitor. NR-PM1 is dominated by secondary inorganic aerosol (55%) and organic aerosol (OA, 42%) during haze periods. Six OA components were identified by positive matrix factorization of the OA mass spectra. The hydrocarbon-like OA and cooking-related OA represent the local traffic and cooking sources, respectively. A highly oxidized factor related to biomass burning OA accounted for 15% of the total OA mass during haze periods. Three types of oxygenated OA (OOA), i.e., a less-oxidized OOA (LO-OOA), a more-oxidized OOA (MO-OOA), and a low-volatility OOA (LV-OOA), were identified. LO-OOA is likely associated with fresh urban secondary OA. MO-OOA likely represents photochemical products showing a similar diurnal cycle to nitrate with a pronounced noon peak. LV-OOA appears to be a more oxidized factor with a pronounced noon peak. The OA composition is dominated by secondary species, especially during haze events. LO-OOA, MO-OOA and LV-OOA on average account for 11%, (18%), 24% (21%) and 23% (18%) of the total OA mass for the haze (clean) periods respectively. Analysis of meteorological influence suggested that regional transport from the northern and southeastern areas of the city is responsible for large secondary and low-volatility aerosol formation.

Recently, haze events frequently occurred in East China. To assess the impacts of aerosols on air quality over the region, we investigate the interannual variations of the total aerosols and the submicron aerosols, in terms of the aerosol mass concentration (AMC) and Fine Mode Fraction (FMF), respectively, using the Moderate Resolution Imaging Spectrometer (MODIS) aerosol products, which can be used for regional air quality assessment, from 2003 to 2013. On average, the AMC distributes as “northern high and southern low”, whereas the FMF shows a “northern low and southern high” pattern. High FMF occurs in the warm seasons, but low FMF appears in the cool seasons. During the 10 years, the AMC shows increasing trend in northern and decreasing trend in southeastern parts of the region, whereas an increasing trend in the FMF is observed over the entire East China, likely related to elevated submicron aerosols from anthropogenic sources. The East Asian summer monsoon impacts the submicron aerosols more than the total aerosols. The enhanced submicron aerosols are responsible for rapid deterioration of air quality in East China in recent years.

In this paper, a highly sensitive biosensor was constructed for peanut allergen Ara h1 detection. The biosensor was constructed by coating a glassy carbon electrode with a chitosan-mutiwalled carbon nanotube nanocomposite and then adding a spongy gold film via electro-deposition to increase the effective area. The probe switched from an "on" to an "off" state in the presence of target DNA, which detached biotin from the electrode surface. This also detached streptavidin-horseradish peroxidase (HRP-SA), which was bound to the electrode via specific interaction with biotin. The HRP-SA catalyzed chemical oxidation of hydroquinone by H2O2 to form benzoquinone, and when it was detached, electrochemical reduction of the signal of benzoquinone could be used to monitor DNA hybridization via chronoamperometry. Under optimum conditions, a wide dynamic detection range (3.91 × 10(-17)-1.25 × 10(-15) mol L(-1)) and a low detection limit (1.3 × 10(-17) mol L(-1)) were achieved for the complementary sequence. Furthermore, the DNA biosensor exhibited an excellent ability to discriminate between a complementary target and a one-base mismatch or non-complementary sequence. The sensor was successfully applied to Ara h1 analysis in peanuts.

Background The atypical protein kinase C isozyme iota (PKCiota) has been proposed as an oncogene based on its transformation property and amplification identified in Caucasian non-small cell lung cancer (NSCLC) patients. Because the geography difference of some genetic aberrance such as EGFR mutations between Caucasian and Asian NSCLC patients has been identified previously, it is important to know whether the PKCiota amplification also occurs in Asian NSCLC patients. Methods The PKCiota gene copy number changes and protein expression in Chinese patients samples were detected by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), respectively. Logistic regression was used to assess the association of PKCiota expression with clinicopathological parameters. siRNA-mediated gene silencing was applied to demonstrate the role of PKCiota in promoting cell growth in PKCiota gene amplified and protein overexpressed cancer cells. Results The result showed that PKCiota gene was amplified in 20.2% (24/119) of the tested primary tumor samples from Chinese NSCLC patients. Interestingly this gene amplification was highly enriched in squamous NSCLC patients (37.1%, 23/62). Further IHC analysis indicated that PKCiota protein was highly expressed (IHC score 2+ and 3+) in 91.6% (109/119) of Chinese NSCLC tumors. Moreover, the PKCiota gene amplification was also correlated with gender, subtype and distant metastasis. Knockdown of PKCiota gene in the PKCiota gene amplified and protein overexpressed cells led to significant growth inhibition. Conclusion Taken together, our data demonstrate that PKCiota is a potential oncogene and therapeutic target in Chinese NSCLC.

A novel cell-based electrochemical biosensor was developed to quantify major shrimp allergen Pen a 1 (tropomyosin) and to assess its immunoglobulin E (IgE)-mediated hypersensitivity. Rat basophilic leukemia (RBL-2H3) mast cells, encapsulated in type I collagen, were immobilized on a self-assembled l-cysteine/gold nanoparticle (AuNPsCys)-modified gold electrode to monitor IgE-mediated mast cell sensitization and activation. The exposure of dinitrophenol-bovine serum albumin (DNP-BSA), as a model antigen that stimulates mast cells, induced a robust and long-lasting electrochemical impedance signal in a dose-dependent manner which efficiently measured degranulation of anti-DNP IgE-stimulated mast cells. Then this mast cell-based biosensor was applied into quantification for the shrimp allergen with anti-shrimp tropomyosin IgE-sensitization. The electrochemical impedance spectroscopy (EIS) results showed that the impedance value (Ret) increased with the concentration of purified shrimp allergen Pen a 1 (tropomyosin) in range of 0.5-0.25 μg mL(-1) with the detection limit as 0.15 μg mL(-1), and the electrochemical result was confirmed by β-hexosaminidase assay and scanning electron microscopic morphological (SEM) analysis. Thus, a simple, label-free, and sensitive method for the determination of shrimp allergens was proposed and demonstrated here, implying a highly versatile biosensor for food allergen detection and prediction.

Background : Ten genes are associated with increased susceptibility to inherited breast cancer have also been associated with population breast cancer risk, and all are involved directly or indirectly in the monoubiquitinated FANCD2–DNA damage repair pathway. We analyzed 13 haplotype blocks in eight of these genes to estimate the breast cancer risk conferred by individual haplotypes. Methods : Haplotype blocks were constructed with 48 tag single-nucleotide polymorphisms (tSNPs) identified in eight breast cancer susceptibility genes, TP53 , PTEN , CHEK2 , ATM , NBS1 , RAD50 , BRIP1 , and PALB2 . Genotyping was performed by SNPscan on 734 female patients and 672 female age-matched controls. Results : Forty-five tSNPs were successfully genotyped by SNPscan, and call rates for each tSNP were above 98.9%. Thirteen haplotype blocks of eight genes were constructed with 41 successfully genotyped tSNPs. We found that seven haplotypes from four haplotype blocks located within three genes ( NBS1 , PTEN , and BRIP1 ) were significantly associated with breast cancer risk. Among these, four haplotypes (ATC in block 1 of NBS1 , GCCCC and GCCCT in block 2 of NBS1 , and GCT in block 2 of BRIP1 ) were correlated with breast cancer risk in sporadic cases (OR (95% CI) 1.350(1.124–1.623), 0.752(0.584–0.969), 0.803(0.649–0.993), and 0.776(0.604–0.997), respectively), and only one haplotype (GGCCT in block 2 of NBS1 ) was significantly associated with breast cancer risk in familial and early-onset cases (OR(95% CI) 1.902(1.134–3.191)). Conclusions : Four haplotypes within two genes ( NBS1 and BRIP1 ) involved in the monoubiquitinated FANCD2–DNA damage–repair pathway are significantly associated with increased sporadic breast cancer risk, while one haplotype within NBS1 is correlated with an increased risk of familial or early-onset breast cancer, indicating that specific haplotypes may be distinct predictors of breast cancer.

Aflatoxin B(1)-lysine adduct (AFB-Lys) is a reliable biomarker for aflatoxin exposure; however, a systematic toxicokinetic evaluation has not been reported. In this study, male F344 rats were orally exposed to single, or repeated, doses of AFB(1) and the toxicokinetics of serum AFB-Lys that followed treatments were investigated. A single-dose of AFB(1) increased serum AFB-Lys levels rapidly peaking at 4h, followed by first-order elimination, through which the half-life was estimated to be 2.31 days. A physiologically based pharmacokinetic model showed that approximately 3.00-3.90% and 1.12-1.98% of the administered AFB(1) doses were converted to serum AFB-Lys adducts at 2h and 24h post treatment, respectively. Repeated AFB(1) exposure at 5-25 μg/kg body weight linearly increased serum AFB-Lys levels for 5 weeks in animals, resulting in a 1-1.5 times higher AFB-Lys level overall. This indicates the potential of this adduct as a reliable biomarker for repeated low dose exposure. Higher dose exposure at 75 μg/kg increased the level of AFB-Lys to a maximum at 2 weeks, followed by a gradual decrease to near plateau level up to 5 weeks. In conclusion, this study systematically evaluated the toxicokinetics of serum AFB-Lys adduct in F344 rats using a physiologically based pharmacokinetic model and robust statistical modeling analysis and provided a firm and clear understanding of the toxicokinetics of this biomarker.

To accurately locate the focal plane of the object in digital particle holography, the integrated gray-level gradient method is presented. This method consists of a conventional edge-sharpness [Es] method and a new method, namely, overall-sharpness [Os] method which is an efficient supplement of the former. The respective scopes of application of above criterions were discussed by using numerical simulation holograms of particles. At last, the integrated gray-level gradient method was applied to the real holograms of dot array target, calibration target and glass bead. The experiment results demonstrate that this method can effectively extract the focal plane of particle.

Au–Pt dentritic nanowires (DNWs) bridging a pair of 10–40 μm spacing electrodes were successfully self-assembled from the corresponding ions solution via deposition of an alternating current (AC). The morphology and the composition of Au–Pt DNWs were characterized by scanning electron microscopy (SEM) and energy-dispersion X-ray (EDX) spectrometer. In the electrolyte of various molar ratios of [AuCl4]−/[PtCl6]2−, Au–Pt DNWs with 8–95 at% Pt were fabricated through applying a constant voltage 8–16 Vpp and varied frequencies of 300 Hz for nucleation and 1 MHz for growth. The DNWs have the diameter range of 100–200 nm. The X-ray diffraction (XRD) results confirmed that the DNWs of 20 or 80at% Pt have the alloy phase structure. Au–Pt DNWs are promising nanomaterials of chemical sensors, bioelectronic circuits and nanoelectronic interconnection.

Fog samples were collected at Pancheng in the Nanjing area of China during December 2006 and December 2007. Fog droplet spectra, surface meteorological elements and visibility were also measured during the same period. The data from PM 10 , SO 2 and NO 2 measurements were obtained from the air quality monitoring networks of Nanjing. The total ionic concentration (TIC) and electrical conductivity (EC) in fog samples, and the local pollutant emissions were one or two orders of magnitude higher than those found in Europe or South America for instance. Pollutants were expected to be mainly from local sources, including factories, plants, freeways, soil sources, house construction, and biomass burning. Advection also contributed to pollution levels in radiation–advection fogs. The scavenging of NH 3 and coarse particles by fog droplets was the main cause for the high mean pH value of 5.9. In-phase temporal evolution of TIC, [SO 4 2− ], [NO 3 − ], SO 2 , NO 2 , PM 10 and S/LWC (S: the surface area of fog droplets per unit volume of air; LWC: liquid water content) was found to be due to the interaction of air pollutants and fog droplets, change of air mass due to advection, and so on. S/LWC seemed to be a better indicator for describing the relationship between TIC and microphysics with respect to LWC. A formula between TIC and S/LWC was derived and the related parameters were discussed. Depositions of chemical species in fog cases were estimated and the result showed that deposition was efficient.

Size-controllable Ag nanoparticle ultrathin films, which were fabricated by vacuum deposition method from high purity Ag wire onto cleaned indium tin oxide conducting glass, have different color fabricated by variation of preparation conditions. The UV/Vis spectra showed that optical absorption peak of these Ag nanoparticle films can be tuned in a range from 457 nm to >650 nm. Scanning electron microscopy images showed that with increasing film thickness Ag particle size was larger. Ag/WO 3 composite films were prepared by cathodic electrodeposition of WO 3 onto the surface of Ag nanoparticle films. Spectroelectrochemistry and electrochromic properties of the resulting composite films were characterized. It was found that the electrochemical and electrochromatic properties of the composite films were adjustable with change the size of Ag nanoparticles in the composite films. Compared with a single component system of WO 3 , a substantial enhancement in the electroactive and electrochromic performance for the Ag embedded WO 3 composite system was clearly observed.