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The most serious and common complication of the medication recommended by World Health Organization (WHO) for tuberculosis (TB) is anti-tuberculosis drugs-induced hepatotoxicity (ATDH). Pregnane X receptor (PXR) is a key factor of ATDH, while Hepatocyte nuclear factor 4α (HNF4α) and hepatocyte nuclear factor 4 alpha-antisense-1 (HNF4α-AS1) may have co-regulating relationship with PXR. This study aimed to explore whether the genetic variants of HNF4α and HNF4α-AS1 are associated with the predisposition of ATDH.TB patients diagnosed in West China Hospital between December 2014 and April 2018 were enrolled. TagSNPs in HNF4α and HNF4α-AS1 gene from the samples of the patients were genotyped with a custom-designed 2×48-plex SNP ScanTM Kit. The frequencies of the alleles, genotypes, genetic models and haplotype distribution of the variants were compared between the case and control groups. The association between SNP and ATDH risk was assessed by single factor logistic regression.Logistic regression analysis showed that none of the 15 genetic variants in HNF4α and HNF4α-AS1 genes were significantly associated with susceptibility to ATDH in the Chinese Han population after Bonferroni correction.A challenge has arisen to the promising application of SNPs in the HNF4α and HNF4α-AS1 genes as genetic markers for ATDH, and further study is needed with a larger sample size.

Cisplatin (CDDP)-based chemotherapy is commonly used to treat advanced non-small cell lung cancer (NSCLC). However, the efficacy is limited by the development of drug resistance. Tripartite motif (TRIM) proteins typically have E3 ubiquitin ligase activities and modulate protein stability. In the present study, we screened for chemosensitivity-regulating TRIM proteins using CDDP-resistant NSCLC cell lines. We show that TRIM17 is upregulated in CDDP-resistant NSCLC cells and tumors compared to CDDP-sensitive counterparts. NSCLC patients with high TRIM17 expression in tumors have shorter progression-free survival than those with low TRIM17 expression after CDDP chemotherapy. Knockdown of TRIM17 increases the sensitivity of NSCLC cells to CDDP both in vitro and in vivo. In contrast, overexpression of TRIM17 promotes CDDP resistance in NSCLC cells. TRIM17-mediated CDDP resistance is associated with attenuation of reactive oxygen species (ROS) production and DNA damage. Mechanistically, TRIM17 interacts with RBM38 and promotes K48-linked ubiquitination and degradation of RBM38. TRIM17-induced CDDP resistance is remarkably reversed by RBM38. Additionally, RBM38 enhances CDDP-induced production of ROS. In conclusion, TRIM17 upregulation drives CDDP resistance in NSCLC largely by promoting RBM38 ubiquitination and degradation. Targeting TRIM17 may represent a promising strategy for improving CDDP-based chemotherapy in NSCLC.

BACKGROUND Isoniazid (INH), rifampicin (RMP), pyrazinamide (PZA), and ethambutol (EMB) are the four most common drugs for the first-line treatment of tuberculosis (TB). Although chemotherapy drugs are widely used in the treatment of TB, and achieved good results, but the side effects, especially anti-tuberculosis drug-induced liver injury (ATDILI), cannot be overlooked. Many researchers have made efforts to uncover the association of cytochrome P450 (CYP) enzyme genetic polymorphisms with ATDILI. In this study, we systematically reviewed and meta-analyzed the relationship between CYP polymorphism and susceptibility to ATDILI. METHODS We carried out literature searches of PubMed, Ovid, the Cochrane Library, Web of Science and Chinese National Knowledge Infrastructure (CNKI). Medical Subject Headings (MeSH) terms including "cytochrome P450 enzyme", "drug-induced liver injury", "polymorphism", "tuberculosis", and "hepatotoxicity" were used as keywords for our searches. RESULTS The pooled odds ratio (OR) of all studies for CYP2E1 to the risk of ATDILI was 1.18 [95% confidence interval (CI): 0.82-1.71]. The articles in this meta-analysis were observed to be mildly heterogeneous. Further subgroup analysis revealed that the patients who receiving a four-drug protocol (INH + RIF + PZA + EMB) or three-drug protocol (INH + RIF + PZA) regimens showed a higher risk of ATDILI than those who receiving INH alone. However, subgroup analyses according to participants' ethnic origin, study type, and the definition of ATDILI produced no statistically significant results. Associations between other genes in the CYP family and ATDILI were indistinct and equivocal. DISCUSSION Our meta-analysis has uncovered an association between CYP2E1 RsaI/PstI polymorphisms and ATDILI, especially among patients who receive a four-drug (INH + RIF + PZA + EMB) or three-drug (INH + RIF + PZA) anti-TB treatment regimen.

This study evaluated the combined effects of biochar and straw on N2O flux and the community compositions of nitrifiers and denitrifiers in the maize season in an intensively farmed area in northern China. The experiment consisted of four treatments: (1) CK (only chemical fertilizer application); (2) C (biochar application); (3) SR (straw application to the field); and (4) C+SR (the application of both biochar and straw). The results indicated that during the maize growing season, N2O flux decreased by 30.3% in the C treatment and increased by 13.2% and 37.0% in the SR and C+SR treatments compared with CK, respectively. NO3--N, NH4+-N, and microbial biomass carbon (MBC) were the main soil factors affecting N2O flux, and they were positively correlated with NO3--N and negatively correlated with MBC in the C treatment and positively correlated with NH4+-N in the SR and C+SR treatments. Both biochar addition and straw return shifted the community compositions of nitrifiers and denitrifiers. N2O production was mainly reduced by promoting the ammonia-oxidizing bacteria (AOB) gene abundance and inhibiting the nirK gene abundance in the C treatment but promoted by inhibiting the AOB and nosZ gene abundances in the SR and C+SR treatments. Nitrosospira (AOB) and Rhizobium (nirK) were the main contributors among the treatments. NO3--N, NH4+-N, and MBC were the main soil factors affecting the denitrifier communities. The predominant species associated with the nirK, nirS, and nosZ genes were positively correlated with NO3--N and MBC and negatively correlated with NH4+-N. These results provide valuable information on the mechanism of N2O production and reduction in biochar- and straw-amended soil under field conditions.

Nitrous oxide (N2O) is a strong greenhouse gas, and it is of great significance for N2O reduction to study the effects of biochar on its production pathway. In this research, the contributions and mechanisms of biochar on autotrophic nitrification (ANF), heterotrophic nitrification (HNF), and denitrification (DF) to N2O emissions were studied by using 15N stable isotopes and high-throughput sequencing after laboratory incubation. The results showed that biochar addition at 2% (B2) significantly reduced the N2O emissions from the ANF by an average of 20.6%, while adding 5% biochar (B5) had no significant effect on the ANF. Both B2 and B5 significantly reduced the N2O emissions from the HNF by 15.7% and 13.2%, respectively, and reduced the N2O emissions from the DF by 40.9% and 11.7%, respectively. B2 enhanced the relative contribution rate of the ANF to N2O emissions by 6.3%, while B5 had little effect on it. Biochar addition significantly changed the copy numbers of the AOA and AOB, as well as the nirK, nirS, and nosZ genes, but it had no significant effect on the community composition of the AOA and had minimal effect on the AOB community. B2 significantly increased the abundance of the genus Rhodococcus of nirK type denitrifiers and had a significant effect on the relative abundance of Cupriavidus and Pseudomonas of the nosZ type denitrifiers. These results revealed that the inhibitory effects of biochar on N2O emissions from nitrification might be attributed to the direct immobilization and adsorption of inorganic N by biochar and to its promotion of the genus Rhodococcus of nirK-type denitrifiers and the genera Cupriavidus and Pseudomonas of the nosZ-type denitrifiers. The soil exchangeable NH4+-N and NO3−-N concentrations were the primary factors affecting the N2O emission rates. These results help to elucidate the effects and mechanisms of biochar on N2O production pathways in agricultural soil.

To clarify the mechanism of biochar on nitrification and denitrification to N

Li2Gd4(MoO4)7: Eu3+/PMMA composite flakes (LGMP: Eu3+) have been obtained via embedding Eu3+-activated LGM polycrystalline precursor powders into polymethyl methacrylate (PMMA). The precursor powder with a size of ∼7 μm is confirmed to form the sea-island-like structure by SEM, which is helpful to the stability of the particle-polymer coexistence network in LGMP: Eu3+ flakes. Differential photon-generating behaviors are revealed under short-wave radiation and the effectiveness of PMMA is verified in reducing the mutual collision probability and avoiding the powder agglomeration. Although the LGMP: Eu3+ system has lower powder content in contrast to the pure precursor, its luminosity is still comparable to the pure one due to its favorable particle dispersibility. Efficient photon-conversion and intense red-emission indicate the organic-inorganic composite of PMMA loaded LGM: Eu3+ system is a potential candidate for solid-state lighting and color displays.

The application of a large amount of inorganic nitrogen (N) fertilizer resulted in an increasing N loss. It is an effective practice that biochar and organic fertilizer replace part of inorganic nitrogen fertilizer. Thus, it is necessary to identify and compare the effects of biochar and organic fertilizer on ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) community structure in saline–alkali soil. Three treatments in triplicate were included in the field experiment: (1) CK (no biochar and organic fertilizer), (2) biochar at 10.0 t ha−1 year−1 (C), and (3) organic fertilizer at 7.5 t ha−1 year−1 (M). The community structures and diversities of AOB and AOA were investigated by Illumina sequencing analysis of gene encoding ammonia monooxygenase subunit A (amoA) and followed by principal component analysis, least discriminant analysis effect size, and redundancy analysis. Biochar and organic fertilizers did not change the diversity of AOA and reduced the relative abundance of Candidatus-Nitrosoarchaeum in maize season, while only biochar increased the relative abundance of Candidatus-Nitrosotenuis in wheat season. The diversity of AOB was significantly reduced in the M treatment, but was not changed in the C treatment in wheat season. Moreover, the relative abundances of Nitrosomonas (CK, 15.1%; C, 6.8%; M, 3.4%) were decreased in the maize season, and the relative abundances of Nitrosovibrio (CK, 9.8%; C, 16.8%; M, 14.5%) were increased in the wheat season in the C and M treatments, which probably related to the changes in soil pH, soil NH4+–N content, and soil salt content (SSC). The lower soil pH, higher NO3−–N content, and SSC resulted in Nitrosospira (maize season: CK, 42.2%; C, 40.7%; M, 62.0%; wheat season: CK, 46.6%; C, 50.7%; M, 65.4%) becoming the dominant genus in the M treatment. Our results indicated that AOB was more susceptible than AOA to biochar and organic fertilizer. Organic fertilizer has significant effects on the diversities and community structure of AOB than biochar associated with the changing in soil pH, salinity, and mineral N.

To evaluate long-term effects of biochar addition and straw return (SR) on N2O fluxes in wheat-maize rotation system, a 2-year field experiment following a 7-year biochar addition and SR was investigated in an intensively managed agricultural soil in the North China Plain (NCP). Four treatments were included: 1) no biochar addition (CK); 2) biochar treatment with 4.5 t ha−1 yr−1 (C1); 3) biochar treatment with 9.0 t ha−1 yr−1 (C2); and 4) all the wheat/maize straw return (SR). The results showed the annual cumulative N2O emissions from C1 treatment were increased by 15.9–16.5%, while C2 treatment suppressed the annual cumulative N2O emissions by 22.8–26.3%. In comparison, straw return suppressed N2O emissions by 13.4–43.6% in the wheat season but increased N2O emissions remarkably by 45.3–53.9% in the maize season. Biochar addition enhanced the copies of AOA, AOB, nirK, nirS, and nosZ genes, while straw return decreased the copies of AOB, nirK, nirS, and nosZ genes at the high N2O emission period in the maize season. The production of N2O in the maize season was mainly driven by the AOB and nosZ genes, and by AOB gene in the wheat season. These results suggest that application of 9.0 t ha−1 yr−1 biochar is a more optimum agricultural strategy for reducing N2O emission in the wheat-maize system.

This research investigated the N2O fluxes and community compositions of nitrifiers and denitrifiers in a winter wheat-summer maize rotation system on the North China Plain. The experiment included three treatments: 1) a control treatment (CK); 2) biochar at 10.0 t ha–1 yr−1 (C); and 3) organic fertilizer at 7.5 t ha−1 yr−1 (M). The application of biochar reduced the cumulative N2O emissions by 47.7% and 62.2% in the maize and wheat seasons, respectively, compared with those of the CK treatment. Organic fertilizer increased the cumulative N2O emissions by 311.1% in the maize season and had no significant effects on them in the wheat season. Organic fertilizer reduced the cumulative N2O emissions by 39.8% in the nonfertilizer period of the maize season. The cumulative N2O emissions in the maize season accounted for 75.2–90.0% of the annual emissions among all the treatments. Biochar and organic fertilizer affected soil N2O emissions mainly by changing soil denitrifiers. In the maize season, the lower abundances of Candidatus Nitrosoarchaeum (AOA-amoA), Nitrosomonas (AOB-amoA), Mesorhizobium (nirK), Magnetospirillum (nirS) and Halomonas (nirS) may result in lower N2O emissions in the biochar treatment, and organic fertilizer had a similar influencing mechanism on N2O emissions during the nonbasic fertilizer and nontopdressing periods of the maize season. In the wheat season, the dominant genus Alicycliphilus (nosZ) was the major contributor to decreasing N2O emissions in the biochar treatment, while there was no biomarker related to N2O emissions in the M treatment. The soil pH, NO3−-N content and water-filled pore space (WFPS) were the key factors shifting the community compositions of nitrifiers and denitrifiers in this study. The application of biochar could be a better practice to improve saline-alkali soil with lower N2O emissions. These findings will improve our understanding of the nitrifiers and denitrifiers response to biochar and organic fertilizer.

This study evaluated the combined effects of biochar and straw on N

Nitrous oxide (N

Mixed pixels universally exist in remote sensing images, and they are one of the main obstacles for further improving the accuracy of land cover recognition and classification. Since the concept of sub-pixel mapping (SPM) is proposed, SPM technology has rapidly become an important method to solve the problem of mixed pixels. To further improve SPM accuracy, this paper first proposes a double-calculated spatial attraction model (DSAM) combining the advantages of the spatial attraction model (SAM) and the pixel swap model (PSM). Then, based on the full validation of the proposed DSAM, how multiple factors affect the SPM accuracy is analyzed using the multispectral remote sensing (MRS) images. Finally, by analyzing the maximum variations in the ranges of the overall accuracy and the kappa coefficient under different multiple factors, the order of factors influencing SPM accuracy is determined as follows: reconstruction scale > image spatial resolution > pixel spatial relationships. The results can serve as a reference for other scholars in setting model parameters and selecting the appropriate remote sensing data, thereby helping them achieve more accurate SPM results.

Few studies are conducted to quantify the effects of enhanced N deposition on soil nitrous oxide (N2O) emission and methane (CH4) uptake in the meadow steppe of Inner Mongolia, China. A two-year field experiment was conducted to assess the effects of nitrogen (N) deposition rates (0, 10, and 20 kg N ha−1 year−1 as (NH4)2SO4) on soil N2O and CH4 fluxes. The seasonal and diurnal variations of soil N2O and CH4 fluxes were determined using the static chamber-gas chromatography method during the two growing seasons of 2008 and 2009. Soil temperature, moisture and mineral N (NH4+-N and NO3−-N) concentration were simultaneously measured. Results showed that low level of (NH4)2SO4 (10 kg N ha−1 year−1) did not significantly affect soil CH4 and N2O fluxes and other variables. High level of (NH4)2SO4 (20 kg N ha−1 year−1) significantly increased soil NO3−-N concentration by 24.1% to 35.6%, decreased soil CH4 uptake by an average of 20.1%, and significantly promoted soil N2O emission by an average of 98.2%. Soil N2O emission responded more strongly to the added N compared to CH4 uptake. However, soil CH4 fluxes were mainly driven by soil moisture, followed by soil NO3−-N concentration. Soil N2O fluxes were mainly driven by soil temperature, followed by soil moisture. Soil inorganic N availability was a key integrator of soil CH4 uptake and N2O emission. These results suggest that the changes of availability of inorganic N induced by the increased N deposition in soil may affect the CH4 and N2O fluxes in the cold semi-arid meadow steppe over the short term.

This study intended to evaluate the combined effects of both biochar and organic fertilizer on nitrous oxide (N2O) fluxes and composition of nitrifier and denitrifier of saline-alkali soil. Therefore, four different treatments such as CK (only chemical fertilizer), B (only biochar), M (only organic fertilizer), BM (B:M = 1:1) were used in this experiment. The results showed that N2O emissions were decreased in B and BM treatments compare to the control. In contrast, N2O emissions were highest before day 12 but lowest after day 19 in M treatment compare to the control. Application of biochar, organic fertilizer and biochar plus organic fertilizer decreased the nirS and nirK genes copies and enhanced the nosZ gene copies which resulting in the lower N2O fluxes. The ammonia-oxidizing bacteria (AOB) amoA and nirK genes copies were significantly increased by organic fertilizer before day 12, leading to high N2O emissions. The genera Nitrosospira (AOB) and Nitrososphaera (ammonia-oxidizing archaea, AOA) assumed absolute superiority. Additionally, Nitrosospira (AOB) was also appeared in nirK-type denitrifiers, illustrating denitrification was carried out by nitrifiers. The genera Azospirillum (nirS), Burkholderia (nosZ) and Polymorphum (nosZ) were dominant in CK. There was only one dominant genus, Mesorhizobium (nosZ) in the B treatment. The genera Mesorhizobium (nirK), Azoarcus (nirS), Kocuria (nirS) and Pseudomonas (nosZ) occupied the main status in the M treatment. The relative abundance of Rhodanobacter (nirS) and Azospirillum (nosZ) were higher in the BM treatment compared with other treatments. Soil water content (SWC), pH, NH4+-N and NO3−-N were the main factors affecting AOB and denitrifiers, which influencing N2O emissions. Overall, combined application of biochar and organic fertilizer can reduce the N2O emission where AOB and nirK-type denitrifier were the main contributors to the N2O emission.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death. Particularly, inflammation is crucial for the progression of NSCLC. In the past few decades, the anti-tumor effects of some traditional Chinese medicinal herbs have caused much attention. This study was designed to investigate the effects of polydatin in the progression of NSCLC. CCK-8 assay, wound healing assay and western blot assay were used to assess the anti-cancer property. Consequently, we showed that polydatin inhibited proliferation and migration of NSCLC cells (A549 and H1299 cells) in a dose-dependent manner. In addition, polydatin suppressed the expression of NLRP3, ASC and pro-caspase-1in NSCLC cells. Activation of NLRP3 inflammasome counteracted the inhibitory effect of polydatin on proliferation and migration of NSCLC cells, suggesting that polydatin suppressed progression of NSCLC through inhibiting NLRP3 inflammasome activation. Furthermore, polydatin was found to down-regulate relative expression of phosphor-NF-κB p65 and activation of NF-κB pathway by TNF-α also abolished the inhibitory effect of polydatin on proliferation and migration of NSCLC cells. In conclusion, our data showed that polydatin acted as an anti-tumor agent to suppress proliferation and metastasis of NSCLC cells. The anti-tumor effect of polydatin was possibly related to the inhibition of NLRP3 inflammation via the NF-κB pathway. Our finding suggested that polydatin might be a potential therapeutic candidate in the treatment of NSCLC.

Drug resistance is an important factor leading to the recurrence and metastasis of Non-Small Cell Lung Cancer (NSCLC). Long non-coding RNAs (LncRNAs) play important roles in drug resistance of tumor cells. The aim of our study was to investigate the mechanism of LncRNA-HOTAIR in regulating drug resistance of NSCLC cells. Our data indicated that HOTAIR was overexpressed in NSCLC cell lines. Silencing of HOTAIR decreased cell proliferation and increased apoptosis of NSCLC cells (A549). Besides that, HOTAIR shRNA transfection suppressed drug resistance of A549 cells to Crizotinib by more effectively inhibiting cell viability and promoting apoptosis compared with HOTAIR scramble group. Moreover, silencing of HOTAIR decreased the number of LC3+ puncta and the expression of Beclin1, p-ULK1 and the ratio of LC3 II/I/in Crizotinib treated A549 cells, indicating that silencing of HOTAIR decreased drug resistance of NSCLC cells might through inhibiting autophagy via the ULK1 pathway. In order to further prove our conclusion, Rapamycin (Rapa), an autophagy inducer, was used in our study. With the adjunction of Rapa, obvious autophagy was induced by increasing the number of LC3+ puncta, the ratio of LC3 II/I and the expression of p-ULK1 compared with Crizotinib + HOTAIR shRNA group. What is more, the activation of autophagy abolished the effect of HOTAIR shRNA on decreasing drug resistance by increasing cell viability and decreasing cell apoptosis. These results supported our conclusion that silencing of HOTAIR decreased drug resistance of NSCLC cells to Crizotinib through inhibition of autophagy via suppressing phosphorylation of ULK1.

To investigate the mechanism of salidroside in improvement of pulmonary fibrosis in rats. Methods: SD rats were subjected to 6 groups: a blank group, a model group, a pirfenidone group, a high-dose salidroside group, a middle-dose salidroside group, and a low-dose salidroside group. The contents of ALB, ALP, LDH, PC-III and COL4, and the expression levels of cathepsin B (CB) and NF-κBp65 in the 6 groups were analyzed. Results: Lung coefficient and oxygen partial pressure in the blank group were lower than those in the model group (P0.05). Compared with the model group, lung coefficients in the pirfenidone group, the high-dose salidroside group, the middle-dose salidroside group, and the low-dose salidroside group were decreased, while oxygen partial pressures were statistically increased (P0.05). The contents of ALB, ALP and LDH in the model group were statistically increased (P0.05) in a dose-dependent manner. Compared with the blank group, the contents of GSH, HYP, PC-III and COL4, and the expression levels of CB and NF-κBp65 in the model group were significantly increased (P0.05), which were attenuated by alidroside in a dose-dependent manner (P0.05). Conclusion: Salidroside can improve pulmonary fibrosis in rats, and the mechanism may be related to reduce the expression of CB and NF-κBp65.目的：探讨红景天苷改善大鼠肺纤维化的相关机制。方法：SD大鼠随机分为空白组、肺纤维化模型组、吡非尼酮组和红景天苷高剂量组、中剂量组、低剂量组。测定6组肺系数，血气分析，检测肺泡灌洗液中白蛋白(ALB)、碱性磷酸酶(ALP)、乳清脱氢酶(LDH)含量，肺组织羟脯氨酸(HYP)含量，血清III型前胶原(PC-III)和IV型胶原(COL4)含量，溶酶体组织蛋白酶B(cathepsin，CB)和NF-κBp65表达的水平。结果：模型组肺系数明显高于空白组(P0.05)，而氧分压明显低于空白组(P0.05)；吡非尼酮组、红景天苷高、中、低剂量组肺系数相比模型组均下降(P0.05)，氧分压则升高(P0.05)。模型组中ALB，ALP，LDH含量较空白组升高(P0.05)；随着红景天苷浓度的增加，ALB，ALP，LDH呈下降趋势(P0.05)。模型组谷胱甘肽(GSH)含量较空白组升高(P0.05)；随着红景天苷浓度的增加，GSH含量呈下降趋势(P0.05)。模型组肺组织中HYP及血清PC-III和COL4含量较空白组升高(P0.05)；随着红景天苷浓度的增加，HYP及血清PC-III和COL4含量呈下降趋势(P0.05)。模型组CB和NF-κBp65表达较空白组升高(P0.05)；随着红景天苷浓度的增加，CB和NF-κBp65表达呈下降趋势(P0.05)。结论：红景天苷能改善大鼠肺纤维化，其机制可能与降低大鼠肺组织的CB和NF-κBp65的表达有关。.

Soil enzymes catalyze key biochemical processes in organic matter decomposition and nutrients cycles and are regarded as indicators of soil quality. In this study, we investigated the impact of 4 consecutive years of biochar (corncob; 360°C) amendment on dynamics of enzyme activities (i.e., invertase, urease, catalase, and alkaline phosphatase) during the winter wheat (Triticum aestivum L.) growing period in Northern China. The experiment consisted of four treatments: control (CK), biochar rate at 4.5 t · ha · y (B4.5), biochar rate at 9.0 t · ha· y (B9.0), and crop straw return (SR). Four times throughout the wheat growth period (i.e., 5 Nov. 2010; 26 Mar. 2011; 25 Apr. 2011; 5 Jun. 2011), we determined the enzyme activities down to the 30-cm depth of the soil profile (i.e., 0–5, 5–10, 10–20, and 20–30 cm). Results showed that there were considerable fluctuations in enzyme activities across the observed period and depths. All enzyme activities decreased significantly in deeper soil horizons. High biochar amendment rates (B9.0) lead to the peak activities of invertase, urease, and phosphatase occurring in the 0- to 5-cm layer on 25 Apr. 2011 samples. The greatest catalase activity under B9.0 was found on 26 Mar. 2011 samples. In addition, the effect by B4.5 and SR on enzyme activities was variable and limited. These data support the conclusion that consecutive application of biochar for 4 years increased enzyme activities, which potentially influence soil nutrients dynamics under field condition, although the effects were dependent on sampling depth and time.

Little information is available regarding the effects of biochar amendment on soil thermal properties and soil temperature, especially under field conditions. The possible changes in soil thermal conductivity, surface reflectance, and temperature resulting from biochar addition might affect other biophysical–chemical processes in the soil. We examined the effects of biochar amendment on the thermal conductivity, surface reflectance, and temperature of soil. Soil thermal conductivity, reflectance, and temperature at a 5-cm depth were measured and monitored in an experimental field using a portable soil thermal property analyzer, a portable full-range spectrometer, and temperature and water potential probes. The field was located in the North China Plain and had been cropped in a winter wheat (Triticum aestivum L.)–maize (Zea mays L.) system for 5 yr. With biochar amendment, soil thermal conductivity was decreased significantly by 3.48 and 7.49% with 4.5 (B4.5) and 9.0 t ha⁻¹ yr⁻¹ (B9.0) of biochar addition, respectively, which was consistent with a decrease in soil bulk density. Soil water potential slightly increased under B4.5 treatment but decreased under B9.0 treatment relative to the control. Reflectance increased in the near-ultraviolet and blue-light wavelengths (350–513 nm) and decreased in the infrared wavelength range (520–2350 nm) with biochar amendment. Biochar amendment reduced diurnal soil-temperature fluctuations on both daily and seasonal scales, although the annual average daily soil temperatures at a 5-cm depth showed no significant difference among treatments. Comparison with the control showed that biochar treatment moderated soil temperature extremes, lowering the temperature when soil temperature was high and raising it when soil temperature was low. This moderating capability was mostly within ±0.4 and ±0.8°C for mean daily temperature and mean diurnal temperature of soil, respectively. The effect of biochar amendment on soil temperatures can be explained by the combined action of changes in soil thermal conductivity and reflectance.

The red-emitting phosphors of (Ca, Eu, M)WO4 (M = Mg, Zn, Li) were prepared through solid-state reactions, and their spectroscopic properties were studied. After the addition of a small amount of Mg2+, Zn2+ or Li+ in (Ca, Eu)WO4, the red-light emission intensity of Eu3+ increases obviously. In the luminescence spectra of the phosphors, the predominant transition emission is 5D0 → 7F2 (616 nm), whereas the other emissions are very weak. The excitation spectra are composed of interweaved ligand-to-metal charge-transfer bands (CTB) of W6+–O2− and Eu3+–O2−, and a few 4f excitation transitions of Eu3+. Among the 4f excitation transitions of Eu3+, there are three strong excitation lines corresponding to 7F0 → 5L6, 7F0 → 5D2 and 7F0 → 5D1 transitions, whose relative excitation intensity ratio is seriously affected when Li+ doped in the host. The new phosphors may be applied as red-emitting phosphors for white light emitting diodes.

Monodisperse, core-shell structured SiO2@Gd-2(WO4)(3):Eu3+ particles were prepared by the sol-gel method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, transmission electron microscopy, photoluminescence (PL) and low-voltage cathodoluntinescence (CL). PL and CL study revealed that the core-shell structured SiO2@Gd-2(WO4)(3):Eu3+ particles show strong red emission dominated by the D-5(0)-F-7(2) transition of Eu3+ at 615 nm with a lifetime of 0.89 ins. The PL and CL emission intensity can be tuned by the coating number of Gd-2(WO4)(3):Eu3+ phosphor layers on SiO2 particles, the size of the SiO2 core particles, and by accelerating voltage and the filament current, respectively.

Sm3+- and Eu3+-doped rare-earth borate glasses (Li2O–BaO–La2O3–B2O3) have been fabricated and characterized optically. The density, refractive index, optical absorption, Judd-Ofelt parameters, and spontaneous transition probabilities have been measured, calculated and analyzed. Sm3+ and Eu3+ emit intense reddish-orange and red lights under blue and UV light excitations, respectively. In Sm3+ and Eu3+ co-doped glasses, the excitation wavelength range of Eu3+ emission is broadened owing to the energy transfer from Sm3+ to Eu3+. This broadening makes the Ar+ 488 nm wavelength laser a powerful excitation source for Eu3+ fluorescence. The rare-earth doped glasses with various visible emissions are useful for developing new color light sources, fluorescent display devices, UV-sensor and tunable visible lasers.

Tb 3+ /Dy 3+ and Eu 3+ /Sm 3+ doped rare-earth borate glasses have been synthesized and characterized. Under UV excitation, Dy 3+ , Tb 3+ , Sm 3+ and Eu 3+ emit intense yellowish white, green, reddish orange and red lights, respectively. In Tb 3+ /Dy 3+ co-doped glasses, the enhancement of Tb 3+ green emission is observed, and the sensitization is related to the efficient energy transfer from Dy 3+ to Tb 3+ . In Eu 3+ /Sm 3+ co-doped glasses, the excitation wavelength range of Eu 3+ emission is broadened owing to the energy transfer from Sm 3+ to Eu 3+ . This broadening makes the Ar + 488 nm wavelength laser a powerful excitation source for Eu 3+ fluorescence. The rare-earth doped glasses with various visible emissions are useful for developing new color light sources, fluorescent display devices, UV-sensor and tunable visible lasers.

We report the optical properties and upconversion emissions from the Er3+ ions in a ZrF4-based glass system ZrF4–ZnF2–AlF3. Judd–Ofelt intensity parameters ( Ω (t) with t=2,4,6) were obtained by analyzing the room temperature absorption spectrum. Upon 800 nm laser excitation, upconversion fluorescence was observed in blue, green and red regions at both 25 and 300 K. The main mechanism appears to be energy transfer among Er3+ ions in excited states. The green and red emissions result from a two-step process while the blue one is owing to a three-step energy transfer process.

Ce3+ and Eu2+ ions codoped calcium magnesium chlorosilicate [Ca8Mg(SiO4)4Cl2] phosphors have been synthesized and characterized. Intense bluish-green light was observed under ultraviolet and blue light excitations. The diffuse reflection, excitation and emission spectra of Ca8Mg(SiO4)4Cl2:Ce3+,Eu2+ were measured at room temperature, and enhancement of Eu2+ emission was confirmed. The fluorescence lifetimes of Ce3+ were measured, and the mechanism of nonradiative energy transfer from Ce3+ to Eu2+ is found to be electric dipole–dipole interaction. The probabilities and efficiencies of nonradiative energy transfer were also calculated, and the results indicate that the efficiency can be as high as 86% in this material system.

The long term effect of biochar application on soil microbial biomass is not well understood. We measured soil microbial biomass carbon (MBC) and nitrogen (MBN) in a field experiment during a winter wheat growing season after four consecutive years of no (CK), 4.5 (B4.5) and 9.0 t biochar ha(-1) yr(-1) (B9.0) applied. For comparison, a treatment with wheat straw residue incorporation (SR) was also included. Results showed that biochar application increased soil MBC significantly compared to the CK treatment, and that the effect size increased with biochar application rate. The B9.0 treatment showed the same effect on MBC as the SR treatment. Treatments effects on soil MBN were less strong than for MBC. The microbial biomass C∶N ratio was significantly increased by biochar. Biochar might decrease the fraction of biomass N mineralized (KN), which would make the soil MBN for biochar treatments underestimated, and microbial biomass C∶N ratios overestimated. Seasonal fluctuation in MBC was less for biochar amended soils than for CK and SR treatments, suggesting that biochar induced a less extreme environment for microorganisms throughout the season. There was a significant positive correlation between MBC and soil water content (SWC), but there was no significant correlation between MBC and soil temperature. Biochar amendments may therefore reduce temporal variability in environmental conditions for microbial growth in this system thereby reducing temporal fluctuations in C and N dynamics.

Er3+-doped Na2O·Cd3Al2Si3O12 glass suitable for making optical waveguide devices has been fabricated and characterized for the first time. The density, the refractive indices, the optical absorption, the Judd–Ofelt parameters and the spontaneous transition probabilities have been measured and calculated. Strong 1.535 μm fluorescence was observed under 973 nm excitation, and its emission cross-section has been determined from the line shape of the emission spectrum and the measured lifetime for the 4 I 13/2 level. The maximum emission cross-section is obtained as 7.28×10 −21 cm 2 at 1.535 μm. Efficient green and weak red upconversion luminescence from Er3+ centers in the sample was observed at room temperature, and the upconversion excitation processes have been analyzed.

Ce 3+ - and Tb 3+ -doped rare earth borate glasses were synthesized and their luminescence properties have been studied. The sample containing Ce 3+ ions has a strong purplish-blue emission and that doped with Tb 3+ emits a green light under UV excitation. The Ce 3+ ions in the host form two kinds of emission centers, owing to different lattice sites occupied by Ce 3+ in the host glass. In the Ce 3+ and Tb 3+ co-activated samples the Ce 3+ ions strongly sensitize the luminescence of the Tb 3+ ions.

In this work, the up-conversion properties of the Ho3+-doped LaF3 upon excitation by a cw red dye laser are reported. Ten groups of emission lines have been detected over a wide spectral range from 13 000 to 22 000 cm−1. Five of them are up-conversion emissions arising from four energy levels: 5G4, 5G6, 5F3 and 5S2(5F4). The strongest up-conversion was observed for the green emission corresponding to the 5S2(5F4)→5I8 transition. The up-conversion mechanism is a sequential two-photon absorption via the 5I7 level upon excited state absorption (ESA) excitation. However, when excited into ground state absorption (GSA) transitions two energy transfers involving either two Ho3+ ions excited in the 5F5 multiplet or one in 5F5 and the other in 5I6 multiplets were suggested.

Efficient upconversion luminescence from the Ho3+ C3v centre in a BaF2 crystal is reported. The red-to-green and red-to-blue upconversion is observed upon pumping with a single cw red dye laser. The upconversion mechanism is assigned as a sequential two-photon excitation process in which the excitation wavelength is resonant with either ground state absorption (GSA) or excited state absorption transitions. The efficient green upconversion with excitation into GSA results from a double-resonant excitation between the 5I8→5F5 and 5I7→5F3 transitions.

Efficient upconversion fluorescence from an Er 3+ center in Ca 3 Al 2 Ge 3 O 12 has been observed, upon pumping with a single red dye laser. The mechanism for the blue upconversion is either a sequential three-photon absorption or an energy transfer process depending on the laser energy being tuned on either the excited state absorption or the ground state absorption transitions. Owing to a double resonant excited state absorption transition character, the three-photon blue upconversion efficiency is relatively high.

The magnetoresistivity of a well-textured (Bi,Pb${)}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{Ca}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathit{y}}$ tape is studied experimentally for a temperature range very close to ${\mathit{T}}_{\mathit{c}}$ (T/${\mathit{T}}_{\mathit{c}}$g0.93) in a very low magnetic-field range (H0.1 T). In this H-T region, the dissipation associated with magnetoresistance curves seems to arise from the granularity induced by the field. As the temperature decreases, related Josephson junctions may well be coupled or even become proximity-effect superconductors, thus the dissipation is dominated by the conventional flux-creep process described by Anderson and Kim. This observation was further confirmed by the temperature dependence of the critical current density ${\mathit{J}}_{\mathit{c}}$(T) at various magnetic fields. The ${\mathit{J}}_{\mathit{c}}$(T) dependence seems to support the hypothesis that the Josephson coupling in the present sample is dominated by superconductor-normal-superconductor proximity-effect junctions.