Hederagenol improves multiple sclerosis by modulating Th17 cell differentiation.

Multiple sclerosis (MS) is a common autoimmune illness that is difficult to treat. The upregulation of Th17 cells is critical in the pathological process of MS. Hederagenol (Hed) has been shown to lower IL-17 levels, although its role in MS pathophysiology is uncertain. In this study, we explore whether Hed could ameliorate MS by modulating Th17 cell differentiation, with the goal of identifying new treatment targets for MS. The experimental autoimmune encephalomyelitis (EAE) mouse model was conducted and Hed was intraperitoneally injected into mice. The weight was recorded and the clinical symptom grade was assessed. Hematoxylin-eosin staining was carried out to determine the extent of inflammation in the spinal cord and liver. The luxol Fast Blue staining was performed to detect the pathological changes in the myelin sheath. Nerve damage was detected using NeuN immunofluorescence staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Immunohistology approaches were used to study alterations in immune cells in the spinal cord. The proportions of T cell subsets in the spleens were analyzed by flow cytometry. RORγt levels were measured using quantitative real-time PCR or Western blot. The activity of the RORγt promoter was analyzed by Chromatin immunoprecipitation. Hed administration reduced the clinical symptom grade of EAE mice, as well as the inflammatory infiltration, demyelination, and cell disorder of the spinal cord, while having no discernible effect on the mouse weight. In addition, Hed treatment significantly reduced the number of T cells, particularly Th17 cells in the spinal cord and spleen-isolated CD4+ T cells. Hed lowered the RORγt levels in spleens and CD4+ T cells and overexpression of RORγt reversed the inhibitory effect of Hed on Th17 differentiation. Hed decreased nerve injury by modulating Th17 differentiation through the RORγt promoter. Hed regulates Th17 differentiation by reducing RORγt promoter activity, which reduces nerve injury and alleviates EAE.

Causal role of immune cells in obstructive sleep apnea hypopnea syndrome: Mendelian randomization study.

BACKGROUND: Despite being one of the most prevalent sleep disorders, obstructive sleep apnea hypoventilation syndrome (OSAHS) has limited information on its immunologic foundation. The immunological underpinnings of certain major psychiatric diseases have been uncovered in recent years thanks to the extensive use of genome-wide association studies (GWAS) and genotyping techniques using high-density genetic markers (e.g., SNP or CNVs). But this tactic hasn't yet been applied to OSAHS. Using a Mendelian randomization analysis, we analyzed the causal link between immune cells and the illness in order to comprehend the immunological bases of OSAHS. AIM: To investigate the immune cells' association with OSAHS via genetic methods, guiding future clinical research. METHODS: A comprehensive two-sample mendelian randomization study was conducted to investigate the causal relationship between immune cell characteristics and OSAHS. Summary statistics for each immune cell feature were obtained from the GWAS catalog. Information on 731 immune cell properties, such as morphologic parameters, median fluorescence intensity, absolute cellular, and relative cellular, was compiled using publicly available genetic databases. The results' robustness, heterogeneity, and horizontal pleiotropy were confirmed using extensive sensitivity examination. RESULTS: Following false discovery rate (FDR) correction, no statistically significant effect of OSAHS on immunophenotypes was observed. However, two lymphocyte subsets were found to have a significant association with the risk of OSAHS: Basophil %CD33dim HLA DR- CD66b- (OR = 1.03, 95%CI = 1.01-1.03, P < 0.001); CD38 on IgD+ CD24- B cell (OR = 1.04, 95%CI = 1.02-1.04, P = 0.019). CONCLUSION: This study shows a strong link between immune cells and OSAHS through a gene approach, thus offering direction for potential future medical research.

5-HMF attenuates inflammation and demyelination in experimental autoimmune encephalomyelitis mice by inhibiting the MIF-CD74 interaction.

The neuroprotective role of 5-hydroxymethyl-2-furfural (5-HMF) has been demonstrated in a variety of neurological diseases. The aim of this study is to investigate the effect of 5-HMF on multiple sclerosis (MS). IFN-γ-stimulated murine microglia (BV2 cells) are considered a cell model of MS. With 5-HMF treatment, microglial M1/2 polarization and cytokine levels are detected. The interaction of 5-HMF with migration inhibitory factor (MIF) is predicted using online databases. The experimental autoimmune encephalomyelitis (EAE) mouse model is established, followed by a 5-HMF injection. The results show that 5-HMF facilitates IFN-γ-stimulated microglial M2 polarization and attenuates the inflammatory response. According to the network pharmacology and molecular docking results, 5-HMF has a binding site for MIF. Further results show that blocking MIF activity or silencing CD74 enhances microglial M2 polarization, reduces inflammatory activity, and prevents ERK1/2 phosphorylation. 5-HMF inhibits the MIF-CD74 interaction by binding to MIF, thereby inhibiting microglial M1 polarization and enhancing the anti-inflammatory response. 5-HMF ameliorates EAE, inflammation, and demyelination in vivo. In conclusion, our research indicates that 5-HMF promotes microglial M2 polarization by inhibiting the MIF-CD74 interaction, thereby attenuating inflammation and demyelination in EAE mice.

Chrysophanol Ameliorates Hemin-Induced Oxidative Stress and Endoplasmic Reticulum Stress by Regulating MicroRNA-320-5p/Wnt3a Pathway in HT22 Cells.

Oxidative stress, endoplasmic reticulum (ER) stress, and neuronal cell apoptosis have been considered as the main pathogenesis factors of brain injury after intracerebral hemorrhage (ICH). Chrysophanol (CHR) has been proved to have neuroprotective effects, but the role and underlying mechanisms of CHR in ICH remain unclear. HT22 cells were dealt with hemin to mimic an in vitro ICH model and then subjected to treatment with or without CHR. The cell viability, apoptosis, ER stress, and oxidative stress were evaluated by conducting the cell counting kit-8 (CCK-8), TdT-mediated dUTP nick end labeling (TUNEL) staining assays, western blot, and corresponding kit, respectively. Further, microRNA-sequencing, bioinformatic analysis, dual-luciferase reporter method, and rescue experiments were conducted to explore the molecular mechanisms of CHR alleviating hemin-induced ER in HT22 cell. Our data revealed that CHR increased cells viability, antiapoptosis, anti-ER stress, and antioxidative stress under conditions of hemin-induced HT22 cell injury. Mechanically, it was observed that Wnt3a was competitively sponged by miR-320-5p, and CHR activated ß-catenin pathway by regulating miR-320-5p/Wnt3a molecular axis. Finally, results from the rescue experiment suggested that CHR inhibited hemin-induced cells apoptosis, ER stress, and oxidative stress through regulating the miR-320-5p/Wnt3a axis in HT22 cells. In conclusion, CHR prevented hemin-induced apoptosis, ER stress, and oxidative stress via inhibiting the miR-320-5p/Wnt3a/ß-catenin pathway in HT22 cells. Our results certified that CHR could be served as a promising treatment for brain damage following ICH.

Influencing pathways of soil microbial attributes on accumulation of heavy metals in brassica (Brassica campestris L. ssp.chinensis var.utilis Tsen et Lee) leaves.

Microbial attributes have a great impact on soil heavy metal bioavailability, yet their influencing pathway on heavy metal accumulation in crop plants remains elusive. This study was aimed to analyze the influencing pathways of microbial attributes, including microbial biomass C and N (MBC and MBN), basal soil respiration (BSR) along with the activities of catalase, urease, and sucrase, on heavy metals (i.e., Cd, Cr, Cu, Ni, Pb, and Zn) accumulation by brassica leaves. Based upon a field investigation close to electroplating factory outlets, 45 pairs of soil and brassica samples were analyzed in the laboratory. Concentrations of heavy metals in brassica leaves declined with sampling distances downstream from the outlets. Redundancy analysis indicated that bioavailable concentrations of Cr, Cu, Ni, and MBC along with catalase activity were the major variables influencing heavy metal accumulation in brassica leaves and accounted for 83% of the accumulation. MBC and catalase activity accounted for 17% of the heavy metal accumulation in brassica leaves. Stepwise regression indicated that catalase activity, MBC, and BSR significantly affected heavy metal accumulation in brassica leaves. Based on structural equation modeling, the pathway coefficient of microbial activities-brassica heavy metals and the pathway coefficient of microbial biomass-brassica heavy metals are 0.122 (P < 0.05), suggesting that these microbial attributes (i.e. MBC along with catalase activities and SBR) could affect heavy metal accumulation in brassica leaves directly. The pathway coefficients of microbial activities-bioavailable heavy metals-brassica heavy metals and microbial biomass-bioavailable heavy metals-brassica heavy metal were -0.541 (P < 0.001) and 0.453 (P < 0.001), respectively, indicating that increase of microbial activities inhibited heavy metal accumulation while increase of microbial biomass promoted heavy metal accumulation, in brassica leaves. These results suggested that heavy metal bioavailability played a mediating role in the influencing pathways of soil microbial attributes on heavy metals in brassica leaves.

Improving understanding of carbon stock characteristics of Eucalyptus and Acacia trees in southern China through litter layer and woody debris.

Surveying the quality and quantity of carbon stock in litter layer and woody debris of Eucalyptus and Acacia plantations is critical in understanding their carbon pools. Here, the focus of the present study was on a number of Eucalyptus and Acacia plantations of different stand aged in the Pearl River Delta region of southern China. The plantation type proved to be a crucial driver of the carbon concentration in litter layer and woody debris, with Acacia exhibiting a superior ability to Eucalyptus to accumulate carbon with stand age in both these materials. The relative contribution of the litter layer and woody debris to the carbon stock of the ecosystem was also significantly higher under mature Acacia (8% and 7%, respectively) than that under mature Eucalyptus (4% and 1%, respectively). Most of the carbon stock within the litter layer was present in the leaf debris. The carbon stock in woody debris was mainly contained in the components within the 10-20 cm diameter class during the primary decay stage, represented as snags in middle-aged and mature Acacia, and as logs for mature Eucalyptus, respectively. The results indicate that both plantation type and stand age influence the characteristics of carbon stored in litter layer and woody debris significantly.

Species choice in mangrove reforestation may influence the quantity and quality of long-term carbon sequestration and storage.

Despite carbon sequestration being an important service of mangrove ecosystems, many mangrove reforestation projects have little consideration of the carbon sequestration capacity of species to be planted. Species selection is mostly based on growth rate and convenience in planting. In this study, to compare the quantity and quality of carbon stored in soil, four habitats were selected in Haijiang River Estuary, southern China to assess the contribution by different mangrove species to sediment carbon pool. Two 12-year-old mangrove forests of the exotic Sonneratia apetala and native Kandelia obovata, respectively, and the adjacent sandflat and mudflat as unvegetated referencing sites had been studied. The total sedimentary organic carbon and active sedimentary organic content in sediment suggested that after 12 years of growth, (1) mangrove forests significantly increased the organic carbon content of sediment; (2) total organic carbon in the K. obovata forest was higher than that of the S. apetala forest; but (3) the carbon pool of the K. obovata forest was less stable than that of the S. apetala forest. These results corroborated with other studies that the sediment carbon pool of S. apetala forests reached a stable state after 13 years of growth, while that of K. obovata forests gradually stabilised upon long-term (>13 years) growth. Our study confirms that K. obovata is more conducive to capture carbon in long-term mangrove reforestation projects, demonstrating that the provision of this service may not be directly related to apparently relevant plant traits such as growth rate.

Changes of ecosystem carbon stock following the plantation of exotic mangrove Sonneratia apetala in Qi'ao Island, China.

Carbon storage is one of the main objectives for mangrove afforestation. Planting of the exotic species Sonneratia apetala can rapidly increase the mangrove area and biomass. Here, we studied the change in vegetation and the soil carbon stocks along the chronosequence of S. apetala plantations in Qi'ao Island, China. Five sites, including rehabilitated S. apetala of different ages (1, 4, 9, and 15 years) and 40-year-old mature native Kandelia obovata forests were investigated. Vegetation biomass and the soil carbon content from 0 to 100 cm were analyzed. The ecosystem carbon density (vegetation and soil) was then calculated. A positive and linear relationship was observed between the vegetation carbon stocks and age of S. apetala. The 15-year-old S. apetala already had a similar biomass to 40-year-old K. obovata. However, its soil and ecosystem carbon densities remained lower than those of K. obovata. Different from K. obovata, the majority of the biomass of S. apetala was reserved within the stem. Mature K. obovata had a larger proportion of soil carbon stock to ecosystem carbon stock. S. apetala can accumulate biomass rapidly, but it had a lower ecosystem carbon stock than the native mature K. obovata.

Proteomics and metabolomics of raw rhubarb and wine-processed rhubarb in the treatment of rats with intracerebral hemorrhage.

BACKGROUND: To explore the mechanisms of raw rhubarb and wine-processed rhubarb treatment in a rat model of intracerebral hemorrhage (ICH). METHODS: After adapting to their environment, 30 male Wistar rats were divided into 5 treatment groups: blank control group (CK) (normal saline), sham operation group (SICH) (normal saline), ICH model group (ICH) (normal saline), ICH + raw rhubarb enema group (RO) (raw rhubarb 3.60 g/kg), and ICH + wine-processed rhubarb enema group (WRO) (wine-processed rhubarb 3.60 g/kg). The rhubarb enema (once a day) was given since 3 days before ICH treatment, and was consistently given until 12 hours, 24 hours, 3 days, and 7 days post operation. Serum oxidative stress and inflammatory markers were detected by ELISA, and differences between raw rhubarb and wine-processed rhubarb treatment in ICH rats were screened by proteomics and metabolomics. RESULTS: Both rhubarb treatments effectively improved oxidative stress and inflammatory responses. After ICH, the proteins and metabolites in the brain tissue were significantly altered. Compared with raw rhubarb, wine-processed rhubarb had a better protective effect by dysregulating amino acid metabolism in the ICH model. CONCLUSIONS: Our study provides a basis for further research into the mechanisms of rhubarb treatment from different processing technologies, and promotes the application of rhubarb as a therapeutic approach to ICH.

Down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in experimental autoimmune encephalomyelitis.

OBJECTIVE: Fas is a positive regulator of Th17 cells differentiation in experimental autoimmune encephalomyelitis (EAE). However, its upstream regulators are still not fully determined. This study was designed to explore the upstream regulators of Fas in regulating Th17 cells differentiation in EAE. METHODS: The mouse model of EAE was established by myelin oligodendrocyte glycoprotein injection. Th17 cells differentiation was induced by IL-23, IL-6 and TGF-ß. RESULTS: Down-regulated Hsp70 and miR-374c and up-regulated Fas were observed in the spleen and brain of EAE mice. Hsp70 overexpression evidently reduced Fas protein level, but not mRNA level. The luciferase reporter assay indicated that miR-374c targets Fas. Overexpression of miR-374c down-regulated the mRNA and protein level of Fas. The concentration of IL-17A in CD4+ T-cells was reduced by miR-374c or Hsp70 overexpression, and Fas overexpression altered this trend. Hsp70 did not regulate the expression of miR-374c, and likewise, miR-374c did not regulate the expression of Hsp70. Further results suggested that Hsp70 and miR-374c regulated Fas expression through different ways to affect Th17 cells differentiation in EAE. CONCLUSIONS: This study suggested that down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in EAE.

Changes in mangrove community structures affecting sediment carbon content in Yingluo Bay of South China.

This study aimed to assess how sediment organic carbon (SOC) dynamics were affected by mangrove community structures. Sediment attributes and community structures of the Avicennia marina, Aegiceras corniculatum, Rhizophora stylosa, and Bruguiera gymnorrhiza communities were analyzed, based upon field investigation in Yingluo Bay of South China. Aboveground biomass (AGB), belowground biomass (BGB) and tree height obviously increased with the self-thinning process, while basal area significantly decreased. The self-thinning exponent was 1.382 for AGB and 1.254 for BGB, conforming to the 4/3 self-thinning rule. However, self-thinning exponent for basal area was only 0.4866. SOC content non-linearly increased with the increase of AGB, BGB, and tree height. Mangrove-derived carbon increased through in situ organic material inputs with mangrove growth. The negative correlation between tree density and SOC content was not in line with the previous studies for planted mangroves. SOC dynamics of natural mangroves may be partially different from planted mangroves.

Distribution and availability of heavy metals in soils near electroplating factories.

Comprehensive understanding of the influence of soil properties on the potential availability of heavy metals could facilitate soil environment management. This study investigated the distribution of heavy metals and their potential availability in paddy and vegetable fields around electroplating factory outlets and irrigated with its wastewater. The potential availability was assessed using secondary phase fraction (SPF) of heavy metals, including acid-soluble, reducible, and oxidizable fractions resulting from BCR sequential extraction procedure. In total, 94 of topsoil samples (0-20 cm) were collected. Total and SPF concentrations of heavy metals as well as soil physicochemical properties were determined. Multivariable statistical analyses (i.e., principal component analysis (PCA) and redundancy analysis (RDA)) were employed. Results showed that total and SPF concentrations of heavy metals in soil decreased (P<0.05) as sampling distance away from the electroplating factories increased, suggesting that sampling distance was the major parameter that affected gradient variations of both total and potential availability of soil heavy metals. According to PCA, soil samples distributed on the PCA axis representing anthropogenic effect, illustrating that the variation of soil properties resulted from irrigation with electroplating wastewater. RDA and stepwise regression indicated that soil Mn oxides, amorphous Fe oxides, silt content, and pH could explain 68.8% and 43.5% of the variation of SPF concentration in paddy and vegetable garden soil, respectively, suggesting they were the most important factors influencing the potential availability of heavy metals in soils. The potential availability of heavy metals in soil was positively correlated with soil Mn oxides but negatively associated with soil amorphous Fe oxides, indicating that Mn oxides enhanced the potential availability of heavy metals while amorphous Fe oxides reduced the potential availability.

Association between CYP3A4 gene rs4646437 polymorphism and the risk of hypertension in Chinese population: a case-control study.

Using a case-control design, we assessed the association between single nucleotide polymorphisms of CYP3A4 gene rs4646437 polymorphism and the risk of hypertension in Chinese population. We recruited 450 hypertension patients from The First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was a significant difference in genotype distribution between case group and control group (χ2 =18.169, P=0.000). The minor A allele was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.000, odds ratio [OR]=1.36, 95% confidence interval [95% CI]: 1.12-1.66). Significant differences were also observed in other gene models: the GA/AA genotype did not increase the risk of hypertension compared with GG genotype (OR=1.16, 95% CI: 0.90-1.49, P=0.259). Compared with GG/GA genotype, the AA genotype also increased the risk of hypertension (OR=2.34, 95% CI: 1.56-3.50, P=0.000). For additive model, the AA genotype was significantly associated with GG genotype (OR=2.25, 95% CI: 1.49-3.42, P=0.000). The same results were found for AA vs GA (OR=2.50, 95% CI: 1.60-3.89, P=0.000). For the allele genotype, the A allele frequency was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.002). The A allele of CYP3A4 rs4646437 was associated with an increased risk for hypertension (OR=1.36, 95% CI: 1.12-1.66, P=0.002). Our results revealed a possible genetic association between CYP3A4 gene rs4646437 and hypertension, and the AA genotype of rs4646437 increased the risk of hypertension in Chinese Han population, and this effect could be confirmed by multivariable analyses.

Interaction between GDF5 gene polymorphisms and environment factors increased the risk of knee osteoarthritis: a case-control study.

Using a case-control design, we assessed the association between single nucleotide polymorphisms (SNPs) of growth and differentiation factor 5 (GDF5)/rs143383 gene and interaction with environments and knee osteoarthritis (KOA). We recruited 288 KOA patients from the First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was significant difference in genotype distribution between case group and control group (χ2 = 22.661, P=0.000). The minor C allele was significantly higher in the case group than that in the control group (20.5 vs 8.1%, P=0.000, odds ratio (OR) = 1.62, 95% confidence interval (CI): 1.29-2.03). Significant differences were also observed in other gene models. For age, all models show significant differences (P<0.05) for those whose age was more than 60 years, and no significant difference was observed for those under 60 years. For non-smoking group, there were significant differences between case group and control group, and for smoker, significance level was found in TT compared with CC and allele gene models. Patients with drinking and Bbody mass index (MI )≥ 24 also showed significant relationship between rs143383 and osteoarthritis (OA) under the following models: TT vs CC (P=0.000, P=0.018), TT/CT vs CC (P=0.043), TT vs CT/CC (P=0.000, P=0.009), and T vs C (P=0.024, P=0.000). Other gene models indicated no significance (P>0.05). Our results revealed a possible genetic association between GDF5 and KOA, and the TT genotype of rs143383 increased the risk of KOA in Chinese Han population. The interaction between GDF5 gene and drinking, smoking, and obesity further increased the risk of KOA.

Forest biomass-carbon variation affected by the climatic and topographic factors in Pearl River Delta, South China.

Subtropical forests function as important carbon sinks for atmospheric CO2. Nonetheless, there remain uncertainties about the effects of climate and topography on subtropical forest biomass-carbon stocks. A continuous biomass expansion factor (BEF) method was applied to forest inventory data to estimate biomass-carbon storage and carbon sink rate, and their changes along with abiotic and biotic factors in the Pearl River Delta (PRD) of South China. BEF equations were built using a set of field-based data. Biomass-carbon increased from 62.92 to 70.56 Mt along with forest growth and increasing forest area during the latest two periods of the national forest inventory (2004-8 and 2009-13). The PRD's forests continued to be net carbon sinks 0.51 t ha-1 yr-1. The PRD's forests have a high potential as biomass-carbon sinks in the future, because 46.75% of the forests are at the young or middle-aged stage. In addition, principal component analysis indicated that both biomass-carbon density and carbon sink rate were positively correlated with the area percentage of mature and over-mature forests, average annual precipitation and minimum temperature, but they were negatively correlated with average annual maximum temperature. Pearson correlation analysis demonstrated that biomass-carbon density and carbon sink rate affected by average altitude, while they were not related to the slope angle.

Aminophylline for treatment of postdural puncture headache: A randomized clinical trial.

OBJECTIVE: To investigate the efficacy and safety of IV aminophylline for patients with postdural puncture headache (PDPH). METHODS: We randomly assigned patients to groups receiving either 250 mg IV aminophylline or a placebo within 3 hours of symptom onset once daily for 2 consecutive days. The primary endpoint was headache severity 8 hours after treatment. We assessed this using visual analog scale (VAS) scores taken from patients in a standing position. We also recorded posttreatment VAS score changes, Patient Global Impression of Change (PGIC) scores, and adverse events. We performed an intention-to-treat analysis. RESULTS: We enrolled 126 patients with PDPH at 5 centers in China (62 assigned to the aminophylline group and 64 to the placebo group). The median age was 37 years, and 96 (76.2%) patients were women. Compared to the placebo-treated patients, the aminophylline-treated patients had significantly lower mean VAS scores 8 hours after treatment (5.34 vs 2.98, p < 0.001) and were significantly more likely to report improvements on the PGIC (39.1% vs 72.6%, p < 0.01). This therapeutic effect was already evident at the 30-minute time point and persisted for 2 days. There was no significant difference in the incidence of adverse events (4.8% vs 1.6%, p = 0.589). CONCLUSIONS: IV aminophylline is an effective and safe early-stage treatment for patients with PDPH. CLINICALTRIALSGOV IDENTIFIER: NCT02522013. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for people with PDPH, IV aminophylline reduces headache severity.

Ecosystem carbon storage in forest fragments of differing patch size.

Forest fragmentation threatens the ecosystem carbon (C) storage. The distribution patterns of ecosystem C density are poorly documented for fragmented forests of differing patch size. The objectives of this study were to examine C density in these forest ecosystems and the influence of edge effects on C density. Allometric equations were used to quantify aboveground biomass. Carbon density was estimated by analyzing the C concentration of each component. We found that ecosystem carbon density ranged from 173.9 Mg ha-1 in the small sized forest fragments, to 341.1 Mg ha-1 in the contiguous evergreen sub-tropical forest. Trees (46.5%) and mineral soil (50.2%) were the two largest contributors to the total ecosystem C pool in all fragments. Both C and nitrogen (N) in soil and fine roots were highly heterogeneous among the different fragment sizes and soil depths. We concluded that ecosystem C density of forest fragments were significantly influenced by patch size and edge effects. The fragmented forests in southern China play an important role in the C budget, and need urgent conservation. These results are likely to be further integrated into forest management plans and generalized into other contexts, to evaluate C stocks at the landscape scale.

The influence of bioavailable heavy metals and microbial parameters of soil on the metal accumulation in rice grain.

A field-based study was undertaken to analyze the effects of soil bioavailable heavy metals determined by a sequential extraction procedure, and soil microbial parameters on the heavy metal accumulation in rice grain. The results showed that Cd, Cr, Cu, Ni, Pb and Zn concentrations in rice grain decreases by 65.9%, 78.9%, 32.6%, 80.5%, 61.0% and 15.7%, respectively in the sites 3 (far-away), compared with those in sites 1 (close-to). Redundancy analysis (RDA) indicated that soil catalase activity, the MBC/MBN ratio, along with bioavailable Cd, Cr and Ni could explain 68.9% of the total eigenvalue, indicating that these parameters have a great impact on the heavy metal accumulation in rice grain. The soil bioavailable heavy metals have a dominant impact on their accumulation in rice grain, with a variance contribution of 60.1%, while the MBC/MBN has a regulatory effect, with a variance contribution of 4.1%. Stepwise regression analysis showed that the MBC/MBN, urease and catalase activities are the key microbial parameters that affect the heavy metal accumulation in rice by influencing the soil bioavailable heavy metals or the translocation of heavy metals in rice. RDA showed an interactive effect between Cu, Pb and Zn in rice grain and the soil bioavailable Cd, Cr and Ni. The heavy metals in rice grain, with the exception of Pb, could be predicted by their respective soil bioavailable heavy metals. The results suggested that Pb accumulation in rice grain was mainly influenced by the multi-metal interactive effects, and less affected by soil bioavailable Pb.

A TiO2 nanotube network electron transport layer for high efficiency perovskite solar cells.

The electron transport layer (ETL) plays a critical role in high efficiency perovskite solar cells. In this study, an anodic TiO2 nanotube film was transformed into a TiO2 nanotube network film, which maintained its advantage as an efficient ETL for perovskite solar cells. Compared with the mesoporous TiO2 nanoparticle ETL, the TiO2 nanotube network ETL can increase the efficiency of perovskite solar cells by 26.6%, which is attributed to its superior charge collection property and light trapping ability. The results confirm the importance of optimizing the electron collecting layer and suggest another way to design and fabricate novel perovskite solid state solar cells, potentially by using a TiO2 nanotube network film as an alternative high efficiency electrode.