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Background Autophagy is a conserved catabolic process, which plays an important role in regulating tumor cell motility and degrading protein aggregates. Chemotherapy-induced autophagy may lead to tumor distant metastasis and even chemo-insensitivity in the therapy of hepatocellular carcinoma (HCC). Therefore, a vast majority of HCC cases do not produce a significant response to monotherapy with autophagy inhibitors. Results In this work, we developed a biomimetic nanoformulation (TH-NP) co-encapsulating Oxaliplatin (OXA)/hydroxychloroquine (HCQ, an autophagy inhibitor) to execute targeted autophagy inhibition, reduce tumor cell migration and invasion in vitro and attenuate metastasis in vivo. The tumor cell-specific ligand TRAIL was bioengineered to be stably expressed on HUVECs and the resultant membrane vesicles were wrapped on OXA/HCQ-loaded PLGA nanocores. Especially, TH-NPs could significantly improve OXA and HCQ effective concentration by approximately 21 and 13 times in tumor tissues compared to the free mixture of HCQ/OXA. Moreover, the tumor-targeting TH-NPs released HCQ alkalized the acidic lysosomes and inhibited the fusion of autophagosomes and lysosomes, leading to effective blockade of autophagic flux. In short, the system largely improved chemotherapeutic performance of OXA on subcutaneous and orthotopic HCC mice models. Importantly, TH-NPs also exhibited the most effective inhibition of tumor metastasis in orthotopic HCCLM3 models, and in the HepG2, Huh-7 or HCCLM3 metastatic mice models. Finally, we illustrated the enhanced metastasis inhibition was attributed to the blockade or reverse of the autophagy-mediated degradation of focal adhesions (FAs) including E-cadherin and paxillin. Conclusions TH-NPs can perform an enhanced chemotherapy and antimetastatic effect, and may represent a promising strategy for HCC therapy in clinics. Graphical Abstract

Background: Nanoparticle albumin-bound paclitaxel (nab-PTX) has exhibited clinical efficacy in breast cancer treatment, but toxicities can be yielded more at the same time. We did this meta-analysis aiming to unambiguously compare nab-PTX with conventional solvent-based paclitaxel (sb-PTX) in breast cancer patients of all stages. Method: Pubmed, Embase and Cochrane Library were searched for head-to-head randomized controlled trials of nab-PTX and sb-PTX in breast cancer. Risk ratio (RR) with 95% confidence interval was used for dichotomous variables while Hazard ratio (HR) was used for time-to-event outcomes. Results: Our review finally included 9 studies with 3508 patients. Nab-PTX showed a benefit on objective response rate (ORR) (RR=1.22 [1.04-1.43], P=0.01) as well as non-inferiority compared with sb-PTX in disease control rate (DCR) (RR=1.01 [0.98-1.04], P=0.44), overall survival (OS) (HR=0.99 [0.93-1.05], P=0.81) and disease free survival/progression free survival (DFS/PFS) (HR=0.92 [0.81-1.05], P=0.21). However, when it comes to toxicities (fatigue, nausea or vomiting, peripheral sensory neuropathy and adverse event related discontinuation), results favored sb-PTX (RR=2.89 [1.07-7.8], 3.15 [1.78-5.59], 2.11 [1.32-3.37], 2.02 [1.61-2.53]; P

The removal of organic matter and iron oxides could increase and decrease soil CEC in tropical and subtropical regions, but the quantitative information is insufficient so far about the change of soil CEC, the influence factors and their contribution. In this study, the subhorizon soils of 24 soil series in the tropical and subtropical China were used, pH, particle size composition, organic matter, iron oxides of these samples were measured, and also CECs were measured and compared for the original soils and after the removal of organic matter and iron oxides. The results showed that, compared with CEC of the original soil, the eliminating organic matter increased soil CEC significantly by 2.28% - 56.50% with a mean of 24.02%, but the further obliterating iron oxides decreased soil CEC significantly by 0.75% - 20.30% with a mean of 7.73%. CEC after the removal of organic matter and iron oxides had positive correlation with iron oxides (p − 0.546pH − 0.024OM + 0.053FexOy − 0.001Silt + 0.007Clay + 0.972CECoriginal (R2 was 0.923, RSME was 1.55 cmol(+)∙kg−1, p − 0.546pH − 0.024OM + 0.053FexOy − 0.001Silt + 0.007Clay + 0.972CECoriginal (R2 was 0.923, RMSE was 1.55 cmol(+)∙kg−1, p < 0.01). Further research is needed in the future as for exploring internal functional mechanism in view of soil electrochemistry and mineralogy.

Sufficient water and fertilizer inputs in agriculture play a major role in crop growth, production, and quality. In this study, the response of sugarcane to limited water irrigation and foliar application of potassium salt of active phosphorus (PSAP) for photosynthetic responses were examined, and PSAP's role in limited water irrigation management was assessed. Sugarcane plants were subjected to limited irrigation (95-90 and 45-40% FC) after three months of germination, followed by a foliar spray (0, 2, 4, 6, and 10 M) of PSAP. The obtained results indicated that limited water irrigation negatively affected sugarcane growth and reduced leaf gas exchange activities. However, the application of PSAP increased the photosynthetic activities by protecting the photosynthetic machinery during unfavorable conditions. Mathematical modeling, a Skewed model, was developed and compared with the existing Gaussian model to describe the photosynthetic responses of sugarcane leaves under the limited irrigation with and without PSAP application. The models fitted well with the observed values, and the predicted photosynthetic parameters were in close relationship with the obtained results. The Skewed model was found to be better than the Gaussian model in describing the photosynthetic parameters of plant leaves positioned over a stem of limited water irrigation and applied PSAP application and is recommended for further application.

Poly(ethylene glycol) (PEG) is well known to endow nanoparticles (NPs) with low-fouling and stealth-like properties that can reduce immune system clearance in vivo, making PEG-based NPs (particularly sub-100 nm) of interest for diverse biomedical applications. However, the preparation of sub-100 nm PEG NPs with controllable size and morphology is challenging. Herein, we report a strategy based on the noncovalent coordination between PEG-polyphenolic ligands (PEG-gallol) and transition metal ions using a water-in-oil microemulsion phase to synthesize sub-100 nm PEG NPs with tunable size and morphology. The metal-phenolic coordination drives the self-assembly of the PEG-gallol/metal NPs: complexation between MnII and PEG-gallol within the microemulsions yields a series of metal-stabilized PEG NPs, including 30-50 nm solid and hollow NPs, depending on the MnII/gallol feed ratio. Variations in size and morphology are attributed to the changes in hydrophobicity of the PEG-gallol/MnII complexes at varying MnII/gallol ratios based on contact angle measurements. Small-angle X-ray scattering analysis, which is used to monitor the particle size and intermolecular interactions during NP evolution, reveals that ionic interactions are the dominant driving force in the formation of the PEG-gallol/MnII NPs. pH and cytotoxicity studies, and the low-fouling properties of the PEG-gallol/MnII NPs confirm their high biocompatibility and functionality, suggesting that PEG polyphenol-metal NPs are promising systems for biomedical applications.

This study aimed to explore the dynamic variations in the phenolic and volatile organic compounds of sugarcane vinegar subjected to different production processes. The determination of phenolic and volatile organic compounds was performed by UPLC-MS and solid phase micro extraction (SPME) coupled with gas chromatography combined with mass spectrometry (GC-MS). The complete fermentation process of sugarcane lasted nine days, and production of vinegar of up to 3.04% (w/v), total acids, and 4.1° alcoholicity was accomplished. Various phenolic compounds of sugarcane juice (non-sterilized) and those of alcoholic and acetic acid fermentation were obtained after nine days of fermentation. These were benzoic acid (2.024, 1.002, and 1.027 mg L-1), ferulic acid (0.060, 0.205, and 1.124 mg L-1), quinic acid (0.019, 0.074, and 0.031 mg L-1), chlorogenic acid (0.349, 1.635, and 1.217 mg L-1), apigenin (0.002, 0.099, and 0.004 mg L-1), kaempferol (0.003, 0.336, and 0.003 mg L-1), caffeic acid (-, 0.005, and 0.005 mg L-1), luteolin (0.003, 0.323, and 0.005 mg L-1), and p-coumaric acid (0.018, 0.015, and 0.027 mg L-1). Forty-five volatile organic compounds were also identified. The sugarcane juice can be commercialized as an alternative to wine as it presents characteristics of an alcoholic fermented beverage.

We report a facile strategy for engineering diverse particles based on the supramolecular assembly of natural polyphenols and a self-polymerizable aromatic dithiol. In aqueous conditions, uniform and size-tunable supramolecular particles are assembled through π–π interactions as mediated by polyphenols. Owing to the high binding affinity of phenolic motifs present at the surface, these particles allow for the subsequent deposition of various materials (i.e., organic, inorganic, and hybrid components), producing a variety of monodisperse functional particles. Moreover, the solvent-dependent disassembly of the supramolecular networks enables their removal, generating a wide range of corresponding hollow structures including capsules and yolk–shell structures. The versatility of these supramolecular networks, combined with their negligible cytotoxicity provides a pathway for the rational design of a range of particle systems (including core–shell, hollow, and yolk–shell) with potential in biomedical and environmental applications., Monodisperse colloidal particles with tunable properties show promise for biomedical, energy, and environmental applications and simple routes for fabricating these particles are of interest. Here, the authors report a facile strategy for fabrication of diverse particles based on the supramolecular assembly of phenols and self-polymerizable thiols

Asparagus stem blight caused by Phomopsis asparagi is a major hindrance to asparagus production worldwide. Currently, fungicides are used to manage the disease in commercial production, but resistance to common fungicides has emerged in the wild population. In the present study, 132 isolates of P. asparagi collected from different provinces in China were tested for sensitivities to pyraclostrobin, tebuconazole, and fluazinam. We also determined the efficacies of six fungicides against P. asparagi. The frequency distributions of EC50 values of the isolates tested were unimodal, but the curves for pyraclostrobin and tebuconazole had long right-hand tails. The mean EC50 values for pyraclostrobin, tebuconazole, and fluazinam were 0.0426 ± 0.0029, 0.6041 ± 0.0416, and 0.0314 ± 0.0013 μg/ml, respectively. In addition, the EC50 values for pyraclostrobin were very similar with or without salicylhydroxamic acid (SHAM), 20 μg/ml, indicating that SHAM is not needed to determine the sensitivity of P. asparagi to pyraclostrobin when using the mycelial growth inhibition assay. In greenhouse assays, Merivon (42.4% fluxapyroxad plus pyraclostrobin SC), Frown-cide (500 g/liter fluazinam SC), Cabrio (250 g/liter pyraclostrobin EC), and Nativo (75% trifloxystrobin plus tebuconazole WG) showed excellent preventive efficacy against P. asparagi. And these fungicides were more effective before inoculation than when they were applied after inoculation (P < 0.05). Therefore, these fungicides should be applied prior to infection to control stem blight. In field trials, Frown-cide, Merivon, Nativo, and Cabrio also performed good control effects, ranging from 75.2 to 86.0% in 2017 and 75.4 to 87.1% in 2018. We demonstrated that Frown-cide, Merivon, Nativo, and Cabrio had considerable potential to manage asparagus stem blight. In addition, rotations of these fungicides are essential for precluding or delaying the development of resistance and for controlling the disease.

Purple paddy soils cover about 66% of the paddy soils in Sichuan Basin. Complex interactions made the effects of potassium fertilizer application on NH4+ adsorption more complicated and the behavior of NH4+ and K+ interaction in purple paddy soils has rarely been evaluated. We hypothesize that correct management of these soils can enhance the efficiency of ammonium and potassium fertilizers. In order to determine correct management methods, it is important to understand the interaction of main nutrient cations NH4+ and K+ and maturation hydroponics in purple paddy soils with different paddy cultivation times. A purple paddy soil chronosequence with cultivation history from 0 to 300 years was studied to understand the respective effects of SOM and mineralogy on NH4+ and K+ sorption behavior by adsorption experiments using samples both before and after H2O2 oxidation. The study shows that maturation hydroponics influenced NH4+ and K+ adsorption mainly through changing clay mineralogy and enhancing SOM accumulation. SOM and smectite play positive effects for NH4+ adsorption. The K+ adsorption, however, is mainly affected by the smectite changes. The adsorption percentages are obviously higher at 25–50 mg L−1 for each NH4+ solution and higher at 50–100 mg L−1 for each K+ solution. When ammonium and potassium were applied together, NH4+ and K+ adsorption are mutually weakened. In addition, the percentage of K+ adsorption increased from 49.7–57.7% for the 100 mg L−1 K+ solution to 50.9–58.5% for the 200 mg L−1 K+ solution at 200 mg L−1 of added NH4+. SOM enrichments could be a positive way to improve the ammonium fertilizer utilization efficiency in purple paddy soils. Potassium may be more vulnerable to loss at low K+ concentrations given that ammonium and potassium fertilizers were applied together and it should be separately applied to enhance the utilization efficiency of applied fertilizer.

Endo/lysosomal escape and gene release are two critical bottlenecks in gene delivery. Herein, a novel photo-controllable metal-organic frameworks (MOFs) nanoswitch is rationally designed for enhancing small interfering RNA (siRNA) delivery. One single laser triggers the “off-to-on” switching of MOFs nanocomplexes, inducing significant siRNA release accompanied by rapid MOFs dissociation into protonatable 2-methylimidazalo and osmotic rupturing Zn2+ ions, which cooperatively contribute to remarkable endo/lysosomal rupture (∼ 90%). The simultaneous endo/lysosomal rupture and release enable a high spatio-temporal control on RNA interference for effective cancer therapy. Notably, the “off-to-on” switching also activates fluorescence recovery for real-time monitoring siRNA delivery. The nanoswitch could easily be extended to deliver other therapeutic agents (e.g., DNA, protein, anticancer drug) for overcoming endo/lysosomal entrapment.

Assembling cellulose nanocrystals (CNCs) can induce solid-state photoluminescence based on Stokes scattering. Such photoluminescence is free of photo-quenching and should have great potential in optical materials, whereas poor flexibility of assembled CNC arrays limits its applications. Here, a co-assembly of binary components including 1D nanoparticles and long-chain polymers had been explored to introduce the uniaxial CNC arrays into a transparent poly (vinyl alcohol) (PVA) membrane, which enhanced the mechanical properties, especially the stretchable property. Besides, the CNC assembly was controlled by adjusting the volume ratio between CNC and PVA. The result indicated that co-assembly with PVA could improve the uniaxial orientation of assembled CNC arrays, which played a crucial role in enhancing the emission quantum-efficiency (EQE) of CNC. Stretching the PVA/CNC membrane could furthermore induce an enhancement in EQE together with a gradual shift in emission wavelength. The mechanism study on that stimulation-response suggested that the enhancement and shift came from the change in the uniaxial orientation degree and periodicity of the CNC assembly, respectively. Since the stimulation-responsive enhancement in EQE (from ca. 40% to ca. 60%) can even be observed by naked eyes, we believe such cellulose-based materials can be widely used in optical sensors.

Nitrate (NO3−) loss and enrichment in water bodies caused by fertilization are a major environmental problem in agricultural areas. However, the quantitative contribution of different NO3− sources, especially chemical fertilizers (CF) and soil organic nitrogen (SON), to NO3− runoff loss remains unclear. In this study, a systematic investigation of NO3− runoff and its sources was conducted in a subtropical agricultural watershed located in Yujiang County, Jiangxi Province, China. A semi-monthly sampling was performed at the inlet and outlet from March 2018 to February 2019. Hydrochemical and dual NO3− isotope (15 N and 18O) approaches were combined to estimate the NO3− runoff loss and quantify the contribution of different sources with a Bayesian isotope mixing model. Source apportionment by Stable Isotope Analysis in R (SIAR) suggested that NO3− in runoff was mainly derived from nitrification of ammonium (NH4+) mineralized from SON (37–52%) and manure/sewage (M&S) (25–47%), while the contribution of CF was relatively small (14–25%). The contribution of various sources showed seasonal variations, with a greater contribution of CF in the wet growing season (March to August). Compared with the inlet which contributed 37–40% to runoff NO3−, SON contributed more at the outlet (49–52%). Denitrification in the runoff was small and appeared to be confined to the dry season (September to February), with an estimated NO3− loss of 2.73 kg N ha−1. The net NO3− runoff loss of the watershed was 34.5 kg N ha−1 yr−1, accounting for 15% of the annual fertilization rate (229 kg N ha−1 yr−1). Besides M&S (22%), fertilization and remineralization of SON (CF + SON) were the main sources for the NO3− runoff loss (78%), suggesting accelerated nitrification of NH4+ from CF (24%) and SON mineralization (54%). Our study indicates that NO3− runoff loss in subtropical agricultural watersheds is dominated by nonpoint source pollution from fertilization. SON played a more important role than CF. Besides, the contribution of sewage should not be neglected. Our data suggest that a combination of more rational fertilizer N application (CF), better management of SON, and better treatment of domestic sewage could alleviate NO3− pollution in subtropical China.

Background Water stress is one of the serious abiotic stresses that negatively influences the growth, development and production of sugarcane in arid and semi-arid regions. However, silicon (Si) has been applied as an alleviation strategy subjected to environmental stresses. Methods In this experiment, Si was applied as soil irrigation in sugarcane plants to understand the mitigation effect of Si against harmful impact of water stress on photosynthetic leaf gas exchange. Results In the present study we primarily revealed the consequences of low soil moisture content, which affect overall plant performance of sugarcane significantly. Silicon application reduced the adverse effects of water stress by improving the net photosynthetic assimilation rate (Anet) 1.35–18.75%, stomatal conductance to water vapour (gs) 3.26–21.57% and rate of transpiration (E) 1.16–17.83%. The mathematical models developed from the proposed hypothesis explained the functional relationships between photosynthetic responses of Si application and water stress mitigation. Conclusions Silicon application showed high ameliorative effects on photosynthetic responses of sugarcane to water stress and could be used for mitigating environmental stresses in other crops, too, in future.

The development of multiple drug resistance (MDR) to chemotherapy and subsequent treatment failures are major obstacles in cancer therapy. An attractive option for combating MDR is inhibiting the expression of P-glycoprotein (P-gp) in tumor cells. Here, we report a novel chemosensitizing agent, XMD8-92, which can down-regulate P-gp. To enhance the specificity of MDR chemotherapy, a promising nanotheranostic micelle system based on poly(ethylene glycol)-blocked-poly(L-leucine) (PEG-b-Leu) was developed to simultaneously carry the anticancer drug doxorubicin, chemosensitizing agent XMD8-92, and superparamagnetic iron oxide nanoparticles (SPIOs). Featured with MDR environmentally responsive dual-targeting capability, controllable drug delivery, and efficient magnetic resonance (MR) imaging characteristics, the prepared nanotheranostics (DXS@NPs) showed outstanding in vitro cytotoxicity on MDR cells (SCG 7901/VCR) with only 53% of cells surviving compared to 90% of DOX-treated cells. Furthermore, efficient tumor inhibition and highly reduced systemic toxicity were exhibited by MDR tumor-bearing mice treated with DXS@NPs. Overall, the environmentally responsive dual-targeting nanotheranostics represent a promising approach for overcoming cancer MDR.

Nitrate accumulation has been reported in the top 1 m and subsurface soil (> 1 m) across arid to semi-humid regions, but not in humid regions. Nitrate inventories through the whole regolith, referred to collectively as soil and saprolite, in humid regions have received little attention to date, likely due to previously assumed low nitrification rates and large nitrogen (N) losses by severe surface runoff and erosion. In order to understand if and how reactive N exists in the below ground (soil and saprolite) in humid environment, the amount of NO3--N, NH4+-N and dissolved organic N (DON) present in the regolith to a depth of 9 m in a typical red soil Critical Zone was investigated under different land uses (upland, woodland and paddy field). The Red Soil Critical Zone Observatory is located in the subtropical Jiangxi Province, China, with a mean annual precipitation of 1795 mm and mean annual potential evapotranspiration of 1229 mm. The examined regoliths were acidic, highly weathered, and mainly clay loam in texture. Results showed that on average 92% (827 ± 97 kg N ha-1) of NO3--N and 82% (521 ± 153 kg N ha-1) of DON were stored at depth (from a depth of 1 m to the bedrock surface) in the upland regolith, while 92% (283 kg N ha-1) of NO3--N and 78% (820 kg N ha-1) of DON were stored at depth in the woodland regolith. Nitrate N significantly accumulated with depth in the upland regolith from the 1- to 4-m depth interval (p < 0.01), while the inventory (632 ± 75 kg N ha-1) in the top 3-m zone accounted for on average 71% of the total. Dissolved organic N significantly accumulated with depth in the upland regolith from the 0- to 3-m depth interval (p < 0.01), while the inventory (408 ± 75 kg N ha-1) in the top 3-m zone accounted for on average 64% of the total. There was no significant accumulation for NH4+-N throughout the upland regolith (p = 0.35). No substantial accumulation of dissolved N was measured at depth in paddy field regoliths with different cultivation ages. The finding that large reservoirs of reactive N can exist in deep regolith rather than in the routinely investigated solum of subtropical regions shows a missing part of the terrestrial N budget and raises concerns about potential 34 groundwater nitrate pollution.

Reinforced concrete structures experience severe durability degradation when subjected to alkali–silica reaction (ASR) and chloride attack. A special electrochemical rehabilitation treatment, containing lithium compound anolyte, has been developed to drive lithium ions into concrete composites and remove chlorides simultaneously, for mitigating both the ASR-induced cracks and the chloride-induced reinforcing steel-bar/fiber corrosion. In this study, the efficiency of the impregnation of lithium ions and the removal of chloride ions through a specific electrochemical treatment is numerically evaluated, which results into the distribution profiles of all typical ionic species. A heterogeneous numerical model, which treats concrete as a three-phase composite, is presented to examine the response of inner structures, especially the interaction between active aggregates and lithium ions that are supposed to mitigate ASR. The ionic interaction between different species, binding and the electrochemical reaction at electrodes are also considered. Through a detailed modelling of multi-phase and multi-species, a systemic parametric analysis based on a series of significant factors during electrochemical treatment (e.g., current density, treatment time, temperature, cathode position and concentration of lithium solution) reveals some important tendencies of ionic electromigration in concrete structures, which are supposed to guide the field applications.

Nitrogen (N)-induced soil acidification has received much attention worldwide. Nitrification and soil N mineralization are two key N cycle processes that affect soil acidification. However, the seasonal dynamics of soil pH under their combined influence is unclear. We studied the effect of N fertilization on soil pH and N transformations using 15N tracing in field lysimeters with soils developed from different parent materials (Quaternary red clay, sandstone, and basalt). Maize was planted with 200 kg N ha−1 yr−1 15N-labeled urea addition. During 7–45 days after fertilization, proton (H+) production due to nitrification of fertilizer N, nitrate (NO3−) leaching, and plant uptake exceeded H+ consumption by base cations mobilization and leaching, resulting in a significant soil pH decline. When nitrification activity decreased (after 45 days), due to exhausted ammonium (NH4+) availability, soil pH rose again. During the fallow period, acid neutralization due to base cation mobilization, and ammonification of soil organic N (SON) offset H+ production caused by nitrification of mineralized SON, leading to a sustained rise in soil pH. After the one-year experiment, no significant soil pH decrease was observed in any of the soils. Parent material had little effect on the seasonal dynamics of soil acidification, which appeared to be controlled by fertilization, environmental factors (temperature and moisture), and plant uptake. In subtropical regions, monitoring of soil pH on an annual basis may mask the effect of N fertilization on soil acidification.

Ultra-small superparamagnetic iron oxide nanoparticles (USPIO-NPs) are widely used as clinical magnetic resonance imaging contrast agents for hepatic diseases diagnosis. USPIO-NPs often damage the hepatocytes and affect the function of liver but its mechanism of action remains unclear. In the present study, USPIO-NPs caused higher cytotoxicity and lactate dehydrogenase (LDH) leakage in hepatic L02 cells than SPIO-NPs. Subsequently, USPIO-NPs affected more genes’ expression than SPIO-NPs analyzed through microarray and bioinformatics analysis. The affected genes were involved in several biological processes, including calcium ion homeostasis, inflammatory response-related leukocyte chemotaxis, and migration. In addition, the level of endoplasmic reticulum (ER) calcium ion was increased by USPIO-NPs. USPIO-NPs also upregulated the genes related to acute-phase inflammation, including IL1B, IL6, IL18, TNFSF12, TNFRSF12, SAA1, SAA2, JAK1, STAT5B, and CXCL14. Furthermore, interleukin-6 (IL-6) secretion was elevated by USPIO-NPs as detected using ELISA. On the other hand, USPIO-NPs changed the morphology of ER and triggered the ER stress and unfolded protein response PERK/ATF4 pathway. Furthermore, blocking ER stress with inhibitor or ATF4 small interfering RNA counteracted IL-6-related acute-phase inflammation and cytotoxicity caused by USPIO-NPs. Taken together, we found that the USPIO-NPs could trigger stronger IL-6-related acute-phase inflammation than SPIO-NPs in hepatocytes. We demonstrated, for the first time, that IL-6-related acute-phase inflammation caused by NPs was regulated by PERK/ATF4 signaling. The PERK/ATF4 pathway explored in this study could be a candidate for diagnostic and therapeutic target against NPs-induced liver injury and cytotoxicity, which would be helpful for USPIO-NPs medical application.

Plant root-derived carbon (C) inputs (Iroot) are the primary source of C in mineral bulk soil. However, a fraction of Iroot may lose directly (Iloss, e.g., via rhizosphere microbial respiration, leaching and fauna feeding) without contributing to bulk soil C pool. This loss has never been quantified, particularly at global scale, inhibiting reliable estimation of soil C dynamics. Here we integrate three observational global datasets including radiocarbon content, allocation of photosynthetically assimilated C, and root biomass distribution in 2,034 soil profiles to quantify Iroot and its contribution to the bulk soil C pool. We show that global average Iroot in the 0-200 cm soil profile is 3.5 Mg ha-1 yr-1, ~80% of which (i.e., Iloss) is lost rather than entering bulk soil. If ignoring Iloss, bulk soil C turnover will be incorrectly estimated to be four times faster. This can explain why Earth system models (in which all Iroot enters bulk soil C pools) predict much faster soil C turnover than radiocarbon-constrained estimates. Iroot decreases exponentially with soil depth, and the top 20 cm soil contains >60% of total Iroot. Actual C input to bulk soil (i.e., Iroot – Iloss) shows a similar depth distribution to Iroot. We also map Iloss and its depth distribution across the globe. Our results demonstrate the global significance of direct C losses which limit the contribution of Iroot to bulk soil C storage; and provide spatially explicit data to facilitate reliable soil C predictions via separating direct C losses from total root-derived C inputs.

Plant cell and water relationship regulates morphological, physiological and biochemical characteristics to optimize carboxylation for enhanced biomass yield in sugarcane. Insufficient water irrigation is one of the serious problems to impair potential yield of agriculturally important sugarcane cash crop by loss in plant performance. Our study aims to reveal consequences of foliar spray of silicon (Si) using calcium metasilicate powder (Wollastonite, CaO.SiO2) to alleviate the adverse effects of limited water irrigation in sugarcane. Silicon (0, 50, 100 and 500 ppm) was applied as foliar spray on normally grown 45 days old sugarcane plants. Further, these plants were raised at half field capacity (50%) using water irrigation precisely up to 90 days under open environmental variables. Consequently, restricted irrigation impaired plant growth-development, leaf relative water content (%), photosynthetic pigments, SPAD unit, photosynthetic performance, chlorophyll fluorescence variable yield (Fv/Fm) and biomass yield. Notably, it has enhanced values of proline, hydrogen peroxide (H2O2), malondialdehyde (MDA), antioxidative defense enzyme molecules viz., catalase (CAT), ascorbate peroxidase (APx) and superoxide dismutase (SOD). The foliar spray of Si defended sugarcane plants from limited water irrigation stress as Si quenched harmful effect of water-deficit and also enhanced the operation of antioxidant defense machinery for improved sugarcane plant performance suitably favored stomatal dynamics for photosynthesis and plant productivity.

Nitrate accumulated deep (>100 cm) in the regolith (soil and saprolite) threatens groundwater quality, but most studies focus only on nitrate nearer the surface (

Nitrate (NO3−) leaching in agroecosystems has caused much concern worldwide due to its negative environmental and health impacts. To evaluate the effect of fertilization on NO3− leaching and soil N accumulation, a two-year 15N tracing study was conducted in subtropical China with field lysimeters packed with non-destructive sampling red soil. 200 kg N ha−1 yr−1 urea (15N abundance of 10%) was applied for maize crops. Fertilization promoted NO3− leaching by 91.5 ± 6.1 and 57.9 ± 15.2 kg N ha−1 yr−1 at 20 and 100 cm depth, respectively. Soil organic nitrogen (SON) pool was the main NO3− source (>60%), especially at surface soil. Fertilizer contributed 19.4 ± 2.0 and 32.8 ± 1.9% to NO3− leaching. At 20 cm depth, besides NO3− leaching accelerated by fertilization during the crop growth period (51.8%), mineralization of SON also resulted in abundant NO3− leaching during the fallow period (48.2%). At 100 cm depth, NO3− leaching significantly increased with the fertilization year due to the continuous NO3− leaching and the delay of NO3− leaching by soil NO3− adsorption. After two-year fertilization, 55.3 ± 2.2% of the applied N accumulated in the soil, leading to a soil N pool increase of 110.0 ± 10.1 kg N ha−1 yr−1. If the fertilization was maintained, the continuous N accumulation poses a potential threat to groundwater quality or drinking water safety. In subtropical red soil regions, to reduce NO3− leaching, NO3− leaching during both the crop growth and fallow period should be taken seriously, and effective management practices, such as cover crops and intensive tile drainage systems, should be carried out to reduce the fertilizer N accumulation and the contribution of SON.

Silicon (Si) plays an important role in the sustainable agriculture industry. The increasing demand for crop production with a significant reduction of synthetic chemical fertilizers and pesticide use is a big challenge nowadays. The use of Si has been proven to be an environmentally sound way of enhancing crop productivity by facilitating plant growth and development through either a direct or indirect mechanism, especially in tropical and subtropical regions. In particular, it has been investigated for its role in water stress management. The aim of the current experiment was to examine the protective role of Si in the photosynthetic capacity of different leaf segments and the ultrastructure of sugarcane (Saccharum officinarm) plants under water stress. Sugarcane cv. GT 42 plants were supplied with 0, 100, 300, and 500 mg L–1 Si and exposed for 60 days under each stress condition such as 100–95, 55–50, and 35–30% of field capacity. For the photosynthetic responses, each leaf was observed and separated into three equal parts (base, middle, and tip). We used intact leaves and were able to assess leaf photosynthetic responses. Under moderate and severe stress conditions, applied Si increased the photosynthesis (base, ∼16–143%; middle, 20–66%; and tip leaf part, 41–71%), transpiration rate (base, 15–97%; middle, 26–68%; and tip leaf part, 6–61%), and stomatal conductance (base, 26–137%; middle, 12–70%; and tip leaf part, 7–75%) in sugarcane plants. Ultrastructural examination of sugarcane leaves using scanning electron microscopy showed the remarkable effects on stomata ultrastructure. Silicon increased plant growth development, photosynthetic efficiency, and biomass/yield, and promoted better adaptation of stomata to drought. This study suggests that the application of Si may be used to increase the stress tolerance of sugarcane plants.

A rapid and sensitive stability indicating HPLC method has been developed and validated for the determination of buprenorphine (BPN) in transdermal patch. Chromatographic separation was achieved isocratically on an XBridge(superscript TM) Shield RP18 column with a mobile phase of acetonitrile/0.063 M ammonium bicarbonate buffer (pH 9.5) (58:42, v/v) at the flow rate of 1.5 mL/min with UV absorbance monitoring at 230 nm. The system performance was evaluated and the result showed that BPN and degradation products were separated. Buprenorphine was subjected to neutral, acidic and basic hydrolysis as well as chemical oxidation to evaluate the specificity. The calibration curve of buprenorphine was linear in the range of 30~70 μg/mL (r=0.9999, n=5). The values of RSD (%) for the intra-day and inter-day precision ranged from 0.04 to 0.22 and 0.65 to 0.88%, respectively. The average of the recovery percentage ranged from 98.86 to 99.36%. The detection limit (DL) and quantitation limit (QL) for buprenorphine were 0.008 and 0.024 μg/mL, separately. The robustness of this method was also evaluated on the small fluctuations of pH in the mobile phase, the mobile phase compositions, and the flow rate. The results of stability studies showed the hydrolysis reaction of buprenorphine followed zero-order kinetics model in acidic and basic environment and followed first-order kinetics model in the presence of hydrogen peroxide. This analytical method was successfully applied to the determination of buprenorphine in transdermal patch and can be used for routine quality control work.

This study was aimed to develop the new transdermal formulation to improve the permeability of buprenorphine. The apparent partition coefficients of buprenorphine were measured using the buffers at pH 1.2 to 10.0 as aqueous phase. The solubility of buprenorphine was 12.97 μg/mL in the 0.1 M phosphate buffer at pH 6.8. The influences of vehicles at different pH, adhesives, and permeation enhancers on the penetration of buprenorphine through nude mouse skin were investigated using the static Franz diffusion cells. The permeation parameter J(subscript ss) of buprenorphine increased along with the reduction of the pH of receptor fluid, and the vehicle at pH 6.8 was used in the following skin permeation studies. The pressure sensitive adhesives (PSA) including polyisobutylene (PIB), polystyrene-block-polyisoprene-block-polystyrene (SIS), and acrylic adhesives were evaluated. The permeability of buprenorphine was higher in the PIB or SIS adhesives than that in the acrylic adhesives under the condition without enhancer. When combined the enhancers with propylene glycol (PG) to improve the penetration of buprenorphine, the permeation-enhancing effects of enhancers were in the following order: lauric acid ＞ linolenic acid ＞ menthol ＞ oleic acid ＞ N-methyl-2-pyrrolidone (NMP) ＞ laurocapram ＞ glabridin. Finally, a matrix-type transdermal delivery system for buprenorphine was formulated using acrylic adhesive, PG, and lauric acid. The Jss parameter was 2.68±0.20 μg/cm^2/h and buprenorphine permeated across the nude mouse skin was 31.68%.

The diamondback moth Plutella xylostella is a serious pest of crucifers. It has high reproductive potential and is resistant to many insecticides. Typically, the last-instar larvae of P. xylostella, before pupation, move to the lower or outer plant leaves to make a loose silk cocoon and pupate inside for adult formation. To better understand this pivotal stage we studied the cocoon-spinning behavior of P. xylostella and measured three successive phases by video-recording, namely the selection of a pupation site, spinning a loose cocoon and padding the scaffold cocoon. Subsequently, we cloned three fibroin genes related to cocoon production, i.e., fibroin light chain (Fib-L), fibroin heavy chain (Fib-H), and glycoprotein P25. A spatio-temporal study of these three fibroin genes confirmed a high expression in the silk glands during the final larval instar silk-producing stage. In parallel, we did an exogenous treatment of the insect molting hormone 20-hydroxyecdysone (20E), and this suppressed fibroin gene expression, reduced the normal time needed for cocoon spinning, and we also observed a looser cocoon structure under the scanning electron microscope. Hence, we demonstrated that the expression levels of key genes related to the synthesis of 20E [the three Halloween genes Spook (Spo), Shadow (Sad), and Shade (Shd)] decreased significantly during spinning, the expression of the 20E receptor (EcR and USP) was significantly lower during spinning than before spinning, and that the expression levels of CYP18-A1 related to 20E degradation were significantly up-regulated during spinning. The significance of the cocoon and the effects of 20E on the cocoon-spinning behavior of P. xylostella are discussed.

A paddy soil chronosequence consisting of four profiles derived from Quaternary red clay (QRC) in Southern China with cultivation history from 0 to 300 years was studied to understand the underlying mechanisms and processes controlling the centennial scale Fe evolution during anthropedogenesis. We evaluated the chronosequencial changes in depth distribution of Fe oxides and Fe isotopic compositions. Results showed that paddy soil development on QRC over a centennial time scale caused increasing profile differentiation of Fe oxides and measurable Fe isotope fractionation. Total Fe and oxide bound Fe as well as the maximum Fe illuviation depth decreased as paddy soils age, leading to significant differences in morphological properties between paddy and non-paddy soils with the same parent material. Selective extractions showed that the weakly-bound, oxide-bound and silicate bound Fe corresponded to 4–18%, 49–81%, and 11–40% of the total Fe, respectively, and these proportions varied with both time and depth due to the redox-related Fe transformation and redistribution. δ56Fe values in the studied paddy soil chronosequence ranged from 0.05‰ to 0.26‰ and exhibited a strong negative correlation with the logarithm of total Fe concentrations, suggesting mass-dependent Fe isotope fractionation occurred as a result of the preferential removal of lighter Fe isotopes during Fe leaching loss under the predominant reducing conditions. However, the Fe isotopic ratio of a specific paddy soil horizon was a result of a complex interaction of different processes, which were summarized and interpreted in our proposed conceptual model of Fe evolution in terraced paddy soils. Further investigations of Fe isotope signatures in the soil-plant-water system with a combination of laboratory simulation and prediction of Fe isotope fractionation under different pedogenic processes are needed to evaluate the relative contribution of multiple processes to Fe isotope fractionation during anthropedogenesis of paddy soils.

Southern corn leaf blight (SCLB) caused by Cochliobolus heterostrophus is a fungal disease that impacts production of corn in China. Fungicides have been the main strategy to manage SCLB. In this study, 276 isolates of C. heterostrophus from seven locations in Fujian Province of China were tested for sensitivity to three demethylation inhibitor (DMI) fungicides. The results indicated that most of the isolates of C. heterostrophus tested were exceptionally sensitive to the three DMI fungicides. Correlation analysis revealed positive association between propiconazole and diniconazole (r = 0.8145, P

The maximum compound stress in the thick wall cylinder is usually the key factor that causes the thick wall cylinder to crack. The existing calculation method for stress–strain under thermo-mechanical impact in thick wall cylinder is suitable for stress analysis in the thermo-elastic range. However, the compound stress of the thick wall cylinder under the thermoplastic condition cannot be well analyzed. In this paper, a method to calculate the compound stress of the thick wall cylinder under the effect of thermal–mechanical impact is proposed, based on the finite difference method and the ideal elastic–plastic model and the Mises yield criterion. This method solves the problem of the compound stress calculation to the tube wall under the thermoplastic condition, which change as a result of the combined effect of thermo-mechanical impact. The compound stress in the wall close to the bore surface at different times during shooting is calculated, taking the firing process of a gun as an example. The calculation results well explain the cause of the formation of the crack and the distribution characteristics of the crack in the bore surface.

A paddy soil chronosequence consisting of five profiles derived from calcareous marine sediments with cultivation history from 0 to 1000 years was studied to understand the underlying mechanisms and processes controlling the millennial scale Fe evolution. We evaluated the chronosequencial changes in depth distribution of Fe oxide contents and Fe isotopic compositions. Results showed that paddy soil evolution under the influence of periodic flooding and groundwater fluctuation resulted with time in variations of soil moisture regime and redox condition that control Fe mobilization, translocation and redistribution, leading to enhanced profile differentiation of Fe oxides and measurable Fe isotope fractionation. Total Fe and oxide bound Fe as well as their differentiation between surface and subsurface horizons increased as paddy soils age, leading to the formation of diagnostic horizons and features characterizing Fe distribution and redistribution. Selective extractions showed that the weakly-bound, oxide-bound and silicate bound Fe corresponded to 1–16%, 8–46%, and 52–91% of the total Fe, respectively, and these proportions varied with both time and depth due to the redox-related Fe transformation and translocation. δ56Fe values in the studied paddy soil chronosequence ranged from − 0.01‰ to 0.18‰ and exhibited a strong negative correlation with the logarithm of total Fe concentrations, suggesting mass-dependent Fe isotope fractionation occurred as a result of the preferential removal of lighter Fe isotopes during long-term paddy soil evolution under the predominant reducing conditions. However, the Fe isotopic ratio of a specific paddy soil horizon was a result of a complex interaction of different processes, which were summarized and interpreted in our proposed conceptual model. Comparison of Fe isotopic compositions in the worldwide soils demonstrated that Fe isotopes can evidence Fe transfer and pinpoint the factors and processes that control Fe mobilization and redistribution particularly in soils with changing moisture regimes and redox conditions. Our findings provide new insights into the behavior and geochemical cycle of Fe at the Earth's surface strongly affected by human activities and contributes to an improved understanding of how anthropedogenesis affects Fe evolution in the Earth's Critical Zone.

This paper was oriented to characterise spatio-temporal variation of soil organic carbon (SOC) over a 30-year period and to explore its driving forces in East China. A comparative study was done of data obtained during 1980 and 2010 in Anhui Province. Spatio-temporal changes of SOC density and storage in the surface (0–30 cm) and 0–100 cm layers were analysed using geographic information system (GIS) spatial analysis techniques. Relationships between soil erosion, land use change, agricultural management, and changes in SOC are discussed. Results show: (1) over 30 years, the average SOC density decreased by 0.59 kg C m−2 in the surface layer and 1.63 kg C m−2 in 0–100 cm layer. The average SOC density increased in Calcaric Cambisols and Haplic Fluvisols, and decreased in other soil types.The average SOC density in upland increased but decreased as a result of other land use practices. (2) SOC density in the surface layer increased to the north but decreased to the south in Anhui. SOC density in the 0–100 cm layer increased in the central area and decreased to the south. About 59% of all soil increased in SOC density. (3) SOC storage decreased by 117.91 Tg C in the surface layer and decreased by 237.65 Tg C in the 0–100 cm layer. The SOC storage increased mainly in the northern and central areas. (4) Severe soil erosion was a main reason for the large reduction in SOC storage in western and southern Anhui. Cultivated land use that changed to paddy field from upland improved SOC more than changes to other land use types. SOC storage change in farmland was significantly and positively related to organic matter content in crop roots.

Increasing acid deposition and intense nitrogen (N) fertilization have resulted in severe soil acidification in many regions of the world. However, the soil acidification rate, especially quantitative contributions of different proton (H+) sources remain unclear in various cropping systems. In this study, a two-year field lysimeter experiment was conducted with a set of different N fertilization treatments (0, 100, 200 and 400 kg N ha−1 yr−1) for maize crop in typical red soil in subtropical China. The pathways and budgets of different H+ sources were quantified by calculating the input–output balance of major elements. Results showed that fertilization significantly accelerated soil acidification by increasing the leaching of NO3– and base cations (K+, Ca2+, Na+, and Mg2+) as well as increasing the cation removals by plant uptake and harvest. Unbalanced plant uptake of anions and cations was the primary H+ source (64.4–80.5%) to soils. Plants have an important effect on soil acidification by redistributing cations in soils. Due to cation removals by plant uptake and harvest, there were significant decreases of soil exchangeable base cations under high urea-N treatments (200 and 400 kg N ha−1 yr−1) and significant increases of soil exchangeable H+ and Al3+ under three fertilization treatments. Of course, N transformation also plays an important role (12.1% to 38.8%). However, the effect of direct H+ deposition is minor in this area comparatively (5.78% to 7.34%). Quantification of acidification contribution of different sources is useful for the establishment of further soil remediation practices. The field management is considered very important to alleviate soil acidification, including increasing straw return and controlling fertilizer application.

Nitrate contamination of water bodies is a serious concern in regions with intensive agriculture. Previous studies, which only considered surface water and groundwater but not the regolith, do not provide a comprehensive accounting of nitrate sources and their proportional contributions in the Critical Zone, which extends from the top of the vegetation canopy down to the bottom of the fresh groundwater. In this study, dual nitrate isotopes, hydrochemical compositions and a Bayesian isotope mixing model were used to investigate nitrate sources, processes and individual source contributions across surface water, regolith and groundwater at the Red Soil Critical Zone Observatory of China. Denitrification was found to be weak in the Critical Zone. Dilution processes were important in eliminating nitrate from streamflow and groundwater. More than 90% of the nitrate inventory was stored at depths from 1 m to the bedrock surface in the upland regolith. Nitrate with light nitrogen (14N) isotopes was preferentially adsorbed by the variable charge soils with the help of weak electrostatic attraction. The contribution of soil organic N (SON) to the nitrate in the upland catchment streamflow was found to be highest with a mean of 56%, followed by manure and sewage (MS, 26%), NH4+ in chemical fertilizers (CF, 17%). For the paddy subcatchment streamflow, the contribution of SON (68%) was highest, followed by CF (19%) and MS (13%). In contrast, for the groundwater, the contributions of CF and SON were 60% and 36%, respectively. For the regolith, the contributions of CF and SON were 72% and 25%, respectively. Thus the most important sources of nitrate were SON for the streamflow and CF for the groundwater and regolith. These findings show that the different partitioning and isotopic fractionation within the regolith strongly affect the sources of nitrate reaching groundwater, compared to the sources reaching surface water.

Calcareous soils are those soils containing layers of carbonate accumulation formed by either secondary accumulation or inheritance of CaCO 3 from calcareous parent materials. These soils are widely distributed in arid, semi-arid and even some humid climate environments. However, in the Chinese Soil Taxonomy (CST, 3rd version), the soils that contain large amounts of CaCO 3 but do not meet requirements of Aridosols are classified as Hapli-Ustic Cambosols. This group also includes many non-calcareous soils and those soils strongly affected by secondary carbonate accumulation together with quite dissimilar soils in terms of their morphology and properties. This study was conducted to determine calcification patterns and calcic processes occurring in representative pedons of calcareous soils in northwestern Henan Province, China and to classify these soils in CST. A Calcic subgroup was proposed to add within the Hapli-Ustic Cambosols. A diagnostic key was also provided to separate this subgroup from the Typic subgroup. In this way the different calcification degrees of soils were better reflected in the classification, which should lead to more uniform interpretive groups for better soil management.

Villosiclava virens is an ascomycete fungus (anamorph: Ustilaginoidea virens) recognized as one of the most economically important pathogens on rice in China that causes false smut disease. In our study, the V. virens cyp51 gene encoding the target protein for fungicide resistant to tebuconazole was cloned. Sequencing showed that fungal mutant strains resistant to tebuconazole harboured the T409C mutation in cyp51. A simple and rapid allele-specific PCR assay was developed to detect the T409C mutation. Among the isolates tested, a unique 391-bp fragment was amplified from resistant mutant strains with primer pair Uv137F1/Uv137DR, whereas no product was amplified from all sensitive isolates. Our study demonstrated that this allele-specific PCR assay is a rapid, simple and reliable method for identification of V. virens mutants resistant to tebuconazole.

Soil organic phosphorus transformation during ecosystem development exerts a crucial influence on soil fertility and ecosystem properties. This paper reviews the use of solution 31P NMR spectroscopy for characterizing organic phosphorus speciation in soil chronosequence and long-term field experiments in order to improve our understanding of the temporal changes, fundamental processes, and associated natural and anthropogenic controls of organic phosphorus transformation during long-term ecosystem evolution. Published soil chronosequence studies show that organic phosphorus compounds under aerobic conditions are dominated by phosphate monoesters (occurred mainly as inositol phosphates) followed by phosphate diesters (occurred mainly as DNA) and phosphonates, irrespective of the different parent materials, vegetation covers and climatic conditions. This contrasted markedly with wetland soils in which phosphate monoesters and diesters maintained approximately equal proportions, which is attributed to the limited reactive clay surfaces for stabilization and/or decomposition of myo-inositol hexakisphosphate under frequent anaerobic conditions. Most organic phosphorus compounds in soil chronosequences increase with age to reach a maximum and then decline with time, although the apex varies significantly among different organic phosphorus compounds and chronosequences. Variations of the potential for phosphorus stabilization resulting from mineralogical transformation, changes in phosphorus sources due to shifts in plant and microbial communities, and differences in the biological utilization of various phosphorus compounds have been suggested as three main mechanisms controlling the temporal changes in organic phosphorus species, abundance and availability during natural ecosystem development. In agricultural soils, the amounts, forms, and dynamics of organic phosphorus are determined by internal soil properties, external environmental conditions and managements, including the history and intensity of land use, different tillage practices and fertilizer treatments. These mechanisms are interlinked and more research is required to isolate both internal and external factors that regulate organic phosphorus transformation in agricultural ecosystems. Given the universal dependence on organic phosphorus for life and its critical roles in biogeochemical cycling, we put forward several open questions that need to be resolved in the future studies by emphasizing the multidisciplinary collaborations, the use of multiple analytical techniques and the establishment of quantitative organic phosphorus transformation models.

Conventional detinning process of lead bullion usually includes the following problems: the oxidizing refining process takes a long time to finish the oxidation of tin and products mass slag, while the basic refining process consumes large reagent, and the labor condition is poor. Therefore, a novel technique with oxygen controlled under vacuum condition for removing tin in crude lead was investigated, which shows characters such as, low-energy consumption, less metal wastage and environmental friendly. During this process, tin was removed from lead bullion by converting to tin oxide and concentrating in the dross. The experimental results showed that the residual Sn-concentration in detinned lead was about 2 ppm corresponding to the lead loss ratio about 2–3 wt% under the following experimental conditions: temperature of 750 °C, oxidation time of 80 min, agitation speed of 100 rpm and air flow rate of 60 mL/min corresponding to the residual gas pressure of 57 KPa.

Calcium leaching is a degradation progress inside hardened cement composites, where Ca2+ ions in cement pore solution can migrate into the aggressive solution. In this work, calcium leaching of graphene oxide (GO) reinforced cement composites was effectively characterized by combined techniques of electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM). Inhibiting mechanism of GO on calcium leaching of the composites was also examined. The obtained results show that the diameter of the semi-circle of the Nyquist curves of leached samples with GO addition decreased less than that of controlled samples. After leaching for 35 days, loss rate of model impedance RCCP of leached samples with 0, 0.05, 0.1, 0.15, and 0.2 wt.% GO addition was 94.85%, 84.07%, 79.66%, 75.34%, and 68.75%, respectively. Therefore, GO addition can significantly mitigate calcium leaching of cement composites, since it can absorb Ca2+ ions in cement pore solution, as well as improve the microstructure of the composites. In addition, coupling leaching depth and compressive strength loss were accurately predicted by using the impedance RCCP.

Implementation of high-volume fly ash (HVFA) in cementitious composites helps reduce matrix toughness and thus improve damping property. In this study, graphene oxide (GO) (0.05%, 0.10%, and 0.20%) and polyvinyl alcohol (PVA) fiber (1% and 2%) were added to enhance the damping ability of the HVFA system. Combined effects of GO and PVA fiber on static/dynamic mechanical properties and interfacial microstructure were studied. The strength tests indicate that incorporating 0.10% GO and 2% PVA fiber can effectively improve 28-d flexural and compressive strengths of the HVFA system by 244.1% and 46.4% respectively, compared with those of the control group (without GO and PVA fiber addition). In addition, a combination of 2% PVA fiber with excessive 0.20% GO content improved the loss factor and energy dissipation ratio by 55.2% and 69.4%, respectively. Microstructural analysis shows that there were several fiber–matrix interfaces, which can dissipate energy under dynamic loading, that were supplemented by the added GO acting as a filler and nucleation site to enhance coulomb friction. Thus, the proposed strategy develops a novel composite with superior damping ability by synergistically using HVFA, GO, and PVA fiber.

Nitrate accumulation at depth in variable charge soils in humid tropics and subtropics affects nitrogen (N) leaching to groundwater. However, the mechanisms on the nitrate accumulation in relation to regolith (soil and saprolite) properties are poorly understood. In this study, four upland regoliths were selected in a typical red soil Critical Zone of humid subtropical China. These regoliths with a thickness of 6–8 m, which developed from Quaternary red clay underlain by sandstone bedrock, were acidic, highly weathered, and clay loam to clay in texture. We analyzed the relationships between nitrate concentrations and the regolith physiochemical properties. The results showed that regolith pH was negatively correlated with nitrate concentrations, whereas crystalline iron (Fe) and aluminum (Al) and anion exchange capacity (AEC) were positively correlated with nitrate concentrations at depths below both soil surface and 1 m. Bulk density (BD) was significantly related to nitrate concentrations only at depths below soil surface, while depth, clay, amorphous Fe and Al, total organic carbon (C), and total N were significantly related to nitrate concentrations only at depths below 1 m. There was no significant correlation between nitrate concentrations and sand, silt, silicate bound Fe or Al, C/N, or moisture at depths below both soil surface and 1 m. Based on the random forest analysis, the relative contributions of pH, crystalline Fe, depth, AEC, BD, crystalline Al and amorphous Fe to explaining nitrate concentration variations were 28.3%, 9.5%, 4.3%, 3.4%, 2.9%, 2.8% and 2.6%, respectively. The concentration of crystalline Fe was ten times that of crystalline Al, which would account for its larger contribution to the nitrate variations. Nitrate accumulation at depth was most likely controlled both by electrostatic adsorption on crystalline Fe and Al oxides and low hydraulic conductivity of the regolith at depth, which appeared to be largely influenced by regolith pH and competitive anions. Our findings shed light on regolith internal property controls on nitrate legacy in the subtropical vadose zone and may help control nitrate contamination of groundwater in intensified agricultural regions.

A supramolecular porous ionic network (SPIN-1) was designed and prepared using a one-pot procedure, involving the quaternization of triimidazole triazine with cyanuric chloride followed by hydrolysis and in situ assembly. The structure of SPIN-1 was characterized by FT-IR, solid-state 13C CP/TOSS NMR, elemental analysis and XPS. SPIN-1 shows a BET surface area up to 263 m2 g−1 (average pore size 11 nm), and a CO2 capture capacity of 24.7 cm3 g−1, which is competitive for Carbon Capture and Storage (CCS).

Soil organic matter (SOM) is a key property determining soil functions and a major form of carbon stored in soil. Understanding the spatial and temporal variability of SOM and the driving forces responsible for spatial and temporal changes is important to assess regional soil quality and carbon sequestration potential and, particularly, to establish better practices for land use and management. We evaluated the spatio-temporal change in SOM content from 1979–1982 to 2006 and its driving forces in Jiangsu Province, East China, using geostatistics. The results showed that mean SOM content increased from 16.60 ± 8.50 to 18.31 ± 8.32 g/kg over a 26-yr period. The maps of SOM generated by ordinary kriging represented the increasing trend from north to south across the province in the two periods. The level of SOM in 1979–1982 affected the pattern of change: the SOM increasing in areas initially with a small content while decreasing in areas having a large content. The map of SOM change showed that the rate of increase decreased from north to south within the province. Increased fertilizer application promoted crop production with more residual biomass being retained in the soil, which resulted in increased SOM content. Land use changes to paddy, upland or forest improved SOM content, whereas abandoning land reduced SOM content.

There is evidence that high levels of nitrate are stored in Earth’s Critical Zone between the land surface and impermeable bedrock. While nitrate in the upper layers of the soil ( 1 m). To study controls on nitrate accumulation in a subtropical monsoon area, a total of 728 regolith samples, taken from land surface to fresh bedrock, were collected from 21 drillings in a typical red soil Critical Zone in southern China. We characterized the variation of nitrate in these deep horizons and investigated the effect of land use, slope position and regolith physiochemical properties. The results showed that the amount of nitrate at 240-380 cm depth was more stable than at 100-240 cm or 380-500 cm depth, and accumulated at that depth in the upland and orchard regoliths. Nitrate contents in the deep horizons of upland and orchard regoliths were significantly larger than that in the paddy fields or woodland (p

There exists an emergency clinical demand to overcome TRAIL/Apo2L (tumor necrosis factor-related apoptosis-inducing ligand) resistance, which is a major obstacle attributed to insufficient level or mutation of TRAIL receptors. Here, we developed an iron oxide cluster-based nanoplatform for both sensitization and MR image-guided evaluation to improve TRAIL/Apo2L efficacy in colorectal cancer, which has an inadequate response to TRAIL/Apo2L or chemotherapy. Specifically, NanoTRAIL (TRAIL/Apo2L-iron oxide nanoparticles) generated ROS (reactive oxygen species)-triggered JNK (c-Jun N-terminal kinase) activation and induced subsequent autophagy-assisted DR5 upregulation, resulting in a significant enhanced antitumor efficacy of TRAIL/Apo2L, which confirmed in both TRAIL-resistant HT-29, intermediately resistant SW-480 and sensitive HCT-116 cells. Furthermore, in a subcutaneous colorectal cancer mouse model, the in vivo tumor retention of NanoTRAIL can be demonstrated by MR T2 weighted contrast imaging, and NanoTRAIL significantly suppressed tumor growth and prolonged the survival time without observable adverse effects compared with control and TRAIL/Apo2L monotherapy. Importantly, in the study of colorectal cancer patient-derived xenograft models, we found that the NanoTRAIL treatment could significantly improve the survival outcome with consistent ROS-dependent autophagy-assisted DR5 upregulation and tumor apoptosis. Our results describe a transformative design that can be applied clinically to sensitize Apo2L/TRAIL-resistant patients using FDA-approved iron oxide nanoparticles.

Fisetin, a natural flavonoid found in a variety of edible and medical plants, has been suggested to inhibit the proliferation of various tumor cells and to induce apoptosis. However, the effects of fisetin on breast cancer have rarely been reported and the underlying mechanism is still undefined. The present study explored the anti-cancer effects of fisetin on mammary carcinoma cells and the underlying mechanisms. Following treatment with fisetin, viability of 4T1, MCF-7 and MDA-MB-231 cells were measured by MTT assay. The inhibitory effects of fisetin on proliferation, migration and invasion were evaluated in 4T1 cells using proliferation array, wound-healing assay, and HUV-EC-C-cell barrier based on electrical cell-substrate impedance sensing platform. Cell apoptosis was analyzed by flow cytometry, and western blotting analysis was performed to identify target molecules. A 4T1 orthotopic mammary tumor model was used to assess the fisetin-inhibition on tumor growth in vivo. Test kits were used to examine the liver and kidney function of tumor-bearing mice. The results suggest that fisetin suppressed the proliferation of breast cancer cells, suppressed the metastasis and invasiveness of 4T1 cells, and induced the apoptosis of 4T1 cells in vitro. The potent anti-cancer effect of fisetin was associated with the regulation of the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway. In vivo experiments demonstrated that fisetin suppressed the growth of 4T1 cell-derived orthotopic breast tumors and enhanced tumor cell apoptosis, and the evaluated alanine amino transferase and aspartate amino transferase levels in serum of tumor-bearing mice suggested that fisetin may lead to side effects on liver biochemical function. The present study confirms that fisetin exerted an anti-mammary carcinoma effect. However, in vivo experiments also revealed that fisetin had low solubility and low bioavailability. Further investigation is required to determine the clinical value of fisetin.