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Riparian vegetation is crucial for maintaining terrestrial and aquatic biodiversity, but it is threatened by land-use activities. To assess the ecological impacts of riparian vegetation conversion to an oil tea (Camellia oleifera) plantation, we quantified the responses of small mammals in two natural habitats (mature forest and flood-meadow) and in Camellia forests at the community, population, and individual level. We found that the community diversity was similar between Camellia forests and mature forests, but higher than the flood-meadow. Meanwhile, the community composition differed across three habitats, with Camellia forests favoring habitat generalist species. At the population level, Camellia forests and flood-meadow had a similar population density, which were higher than mature forests. At the individual level, Rattus nitidus was less sensitive to this conversion, but the body condition index of Niviventer confucianus was higher in Camellia forests than in mature forests, and Apodemus agrarius in Camellia forests had more ectoparasite load than in the flood-meadow, indicating a species-specific response to the impacts of oil tea plantation. Our study highlights that the occurrence of habitat generalist species and high ectoparasite loads may threaten regional biodiversity and increase the risk of parasite transmission with enlarging the oil tea plantation area within riparian zones.

The postmortem diagnosis of acute myocardial infarction (AMI), especially the postmortem diagnosis of early AMI that died immediately after onset or within 1 hour, has always been a difficulty in forensic identification. This article reviews the forensic application of diagnosis and analysis methods for AMI postmortem diagnosis including autopsy imaging, histomorphology, immunohisto-chemistry, biochemical marker and molecular biology diagnosis, and explores the feasible scheme of early postmortem diagnosis in AMI.急性心肌梗死，特别是发病后立即或1 h内死亡的早期急性心肌梗死的死后诊断一直是法医学鉴定的难点。本文就急性心肌梗死死后诊断的虚拟解剖、组织形态学、免疫组织化学、生物化学标志物及分子生物学等诊断、分析方法的法医学应用进行综述，并探索早期急性心肌梗死死后诊断的可行方案。.

To study the annual variation of diatoms in Zhangweixin River, to provide theoretical support by using diatom examination to estimate the time and place of the corpse entering water, and to establish a diatom database.Samples were taken from 4 sampling sites in Decheng section of Zhangweixin River for 12 consecutive months. Non-metric multi-dimensional scaling (NMDS) analysis was performed on the species and content of diatom samples. Based on the sampling site of Tianqu Road, Sprensen similarity coefficient analysis was conducted with the data of other 3 sites in Decheng section and Leling section of Zhangweixin River and Ningjin section in previous studies.The number of diatom species was positively correlated with diatom content. The average diatom content in different months ranged from 1 054 to 13 041/10 mL, and the species composition ranged from 8 to 16, with differences in dominant species. The similarity coefficient of diatom species within 2 km were all higher than 0.956 52, which could not be distinguished effectively. The similarity coefficients of Leling section and Ningjin section were 0.736 84 and 0.588 24 respectively, which could be effectively distinguished.The species and content of diatom vary in different months in Zhangweixin River, and the composition of diatom species is different in different basins, which can provide reference for estimating the time and place of the corpse entering water in the river.

Particle erosion of C/C-SiC composites prepared by reactive melt infiltration with different Al addition was studied by gas-entrained solid particle impingement test. SEM, EDS and XRD were performed to analyze the composites before and after erosion. The results indicate that a U shape relationship curve presents between the erosion rates and Al content, and the lowest erosion rate occurs at 40 wt% Al. Except for the important influence of compactness, the increasing soft Al mixed with reactive SiC, namely the mixture located between carbon and residual Si also, plays a key role in the erosion of the C/C-SiC composites through crack deflection, plastic deformation and bonding cracked Si.

To observe the progress of disease activity and sacroiliac joint imaging in patients with ankylosing spondylitis treated by extracorporeal shockwave combined with conventional oral medicine, and find a new safe and effective therapeutic method.The clinical data of 30 patients with ankylosing spondylitis treated from January 2018 to December 2018 were retrospectively analyzed. Including 20 males and 10 females, aged from 18 to 50 years with an average of (34.50±9.60) years. All 30 patients had different degrees of sacroiliac joint bone marrow edema on MRI before treatment. Thirty patients were divided into treatment group and control group according to different treatment methods. Among them, 15 cases in control group were treated with non-steroidal anti-inflammatory drugs and sulfasalazine enteric-coated tablets, for the 15 cases in treatment group, in addition to oral medicine in line with control group, electronic focusing high-energy extracorporeal shockwave therapy was added. The course of disease, age, pre- and post-treatment erythrocyte sedimentation rate, C-reactive protein in the two groups were analyzed; and visual analogue scale (VAS) and spondyloarthritis research consortium Canada (SPARCC) scoring system were used to evaluate the pain of the sacroiliac joint and the structural damage of the sacroiliac joint;Bath ankylosing spondylitis disease activity index (BASDAI) was calculated.All patients were followed up for at least 3 months. One month after treatment, VAS, and SPARCC scores in treatment group were significantly better than in control group (P0.05). After 1 month of treatment, there was no significant difference in BASDAI, erythrocyte sedimentation rate and C-reactive protein between two groups(P0.05). VAS, BASDAI, SPARCC, erythrocyte sedimentation rate, and C-reactive protein of all patients after treatment were significantly improved compared with those before treatment (P0.01).Electronic focusing high-energy extracorporeal shockwave combined with conventional oral medicine in the treatment of ankylosing spondylitis has a good clinical effect in rapidly relieving pain, improving disease activity, and preventing imaging progress. In addition, it is safe and non-invasive, which is worthy of clinical application.

Circular RNAs (circRNAs) have been increasingly linked to cancer progression. However, the detailed biological functions of circRNAs in prostate cancer (PCa) remain unclear. Using high-throughput circRNA sequencing, we previously identified 18 urine extracellular vesicle circRNAs that were increased in patients with PCa compared with those with benign prostatic hyperplasia. Spearman correlation analysis of the expression levels of the 18 circRNAs between the tumor tissue and matched urine extracellular vesicles in 30 PCa patients showed that circSCAF8 had the highest R2 (R2 = 0.635, P P = 0.022). Mechanistically, circSCAF8 can function by binding to both miR-140-3p and miR-335 to regulate LIF expression and activate the LIF-STAT3 pathway that leads to the growth and metastasis of PCa. Collectively, our findings demonstrate that circSCAF8 contributes to PCa progression through the circSCAF8-miR-140-3p/miR-335-LIF pathway.

Summary Autophagy is a conserved biological process that maintains cell homeostasis by targeting macromolecules for lysosome-mediated degradation. The levels of autophagy are relatively lower under normal conditions than under stress conditions (e.g., starvation), as autophagy is usually stimulated after multiple stresses. However, many autophagy-related regulators are still expressed under normal conditions. Although these regulators have been studied deeply in autophagy regulation, the nonautophagic roles of these regulators under normal conditions remain incompletely understood. Here, we found that autophagy-related 5 (ATG5), which is a key regulator of autophagy, regulates c-Myc protein degradation under normal conditions through the ubiquitin-proteasome pathway. We also found that ATG5 binds c-Myc and recruits the E3 ubiquitin-protein ligase FBW7 to promote c-Myc degradation. Moreover, ATG5-mediated degradation of c-Myc limits cell growth under normal conditions and is essential for embryonic stem cell differentiation. Therefore, this study reveals a nonautophagic role of ATG5 in regulating of c-Myc protein degradation., Graphical abstract, Highlights • ATG5 differentially regulates cell growth between normal and starvation conditions • ATG5 recruits FBW7 to regulate c-Myc protein degradation under normal conditions • ATG5-mediated degradation of c-Myc limits cell growth under normal conditions • ATG5 negatively regulates the protein level of c-Myc during ESC differentiation, Cell biology; Functional aspects of cell biology

Peripheral T‑cell lymphomas (PTCLs) are heterogeneous malignancies that are types of non‑Hodgkin lymphomas; patients with this disease have poor prognoses. The IL‑2‑inducible T‑cell kinase‑spleen tyrosine kinase (ITK‑SYK) fusion gene, the first recurrent chromosome translocation in PTCL‑not otherwise specified (NOS), can drive cellular transformation and the development of T‑cell lymphoma in mouse models. The aim of the current study was to investigate the signal transduction pathways downstream of ITK‑SYK. The authors constructed a lentiviral vector to overexpress the ITK‑SYK fusion gene in Jurkat cells. By using Signal‑Net and cluster analyses of microarray data, the authors identified the tyrosine‑protein kinase JAK (JAK)3/STAT5 signalling pathway as a downstream pathway of ITK‑SYK, activation of which mediates the effects of ITK‑SYK on tumourigenesis. JAK3‑selective inhibitor tofacitinib abrogated the phosphorylation of downstream signalling molecule STAT5, supressed cell growth, induced cell apoptosis and arrested the cell cycle at the G1/S phase in ITK‑SYK+ Jurkat cells. In a xenograft mouse model, tumour growth was significantly delayed by tofacitinib. Since JAK3 associates with interleukin‑2 receptor subunit γ (IL2RG) only, siRNA‑specific knockdown of IL2RG showed the same effect as tofacitinib treatment in vitro. These results first demonstrated that the activation of the IL2RG/JAK3/STAT5 signalling pathway contributed greatly to the oncogenic progress regulated by ITK‑SYK, supporting further investigation of JAK3 inhibitors for the treatment of PTCLs carrying the ITK‑SYK fusion gene.

Summary Histones are main components of chromatin, and the protein levels of histones significantly affect chromatin assembly. However, how histone protein levels are regulated, especially whether and how histones are degraded, is largely unclear. Here, we found that histone H2B is mainly degraded through the proteasome-mediated pathway, and the lysine-120 site of H2B is essential for its K48-linked polyubiquitination and degradation. Moreover, the degradation-impaired H2BK120R mutant shows an increased nucleolus localization, and inhibition of the proteasome results in an elevated nucleolus distribution of wild-type H2B, which is similar to that of H2BK120R mutants. More importantly, the nucleolus fractions can ubiquitinate and degrade the purified H2B in vitro, suggesting that the nucleolus, in addition to its canonical roles regulating ribosome genesis and protein translation, likely associates with H2B degradation. Therefore, these findings revealed a novel mechanism for the regulation of H2B degradation in which a nucleolus-associated proteasome pathway is involved., Graphical abstract, Highlights • Histone H2B can be polyubiquitinated at the lysine 120 residue • The degradation of histone H2B is achieved via the ubiquitination-proteasome pathway • The nucleolus regulates the protein degradation of histone H2B, Biochemistry; Cell Biology

Recently, studies on competing endogenous RNA (ceRNA) networks have become prevalent, and circular RNAs (circRNAs) have crucial implications for the development and progression of carcinoma. However, studies relevant to metastatic prostate cancer (mPCa) are scant. This study aims to discover potential ceRNAs that may be related to the prognosis of mPCa. RNA-Seq data were obtained from the MiOncoCirc database and Gene Expression Omnibus (GEO). Differential expression patterns of RNAs were examined using R packages. Circular RNA Interactome, miRTarBase, miRDB and TargetScan were applied to predict the corresponding relation between circRNAs, miRNAs and mRNAs. The Gene Ontology (GO) annotations were performed to present related GO terms, and Gene Set Enrichment Analysis (GSEA) tools were applied for pathway annotations. Moreover, survival analysis was conducted for the hub genes. We found 820 circRNAs, 81 miRNAs and 179 mRNAs that were distinguishingly expressed between primary prostate cancer (PCa) and mPCa samples. A ceRNA network including 45 circRNAs, 24 miRNAs and 56 mRNAs was constructed. In addition, the protein–protein interaction (PPI) network was built, and 10 hub genes were selected by using the CytoHubba application. Among the 10 hub genes, survival analysis showed that ITGA1, LMOD1, MYH11, MYLK, SORBS1 and TGFBR3 were significantly connected with disease-free survival (DFS). The circRNA-mediated ceRNA network provides potential prognostic biomarkers for metastatic prostate cancer.

Autophagy is a conserved biological process that maintains cell homeostasis mainly by targeting macromolecules or organelles for lysosome-mediated degradation. The levels of autophagy are relatively lower under normal conditions than under stress conditions (e.g., starvation or infection), as autophagy is usually stimulated under such stress conditions. However, many autophagy-related regulators are still expressed under normal conditions. Although these regulators have been studied in depth in the context of autophagy regulation, the nonautophagic roles of these regulators under normal conditions remain incompletely understood. Here, we found that autophagy-related 5 (ATG5), which is a key regulator of autophagy, regulates c-Myc protein degradation under normal conditions through the ubiquitin-proteasome pathway. We also found that ATG5 binds c-Myc and recruits the E3 ubiquitin-protein ligase FBW7 to promote c-Myc protein degradation. Moreover, ATG5-mediated regulation of c-Myc limits cell growth under normal conditions and is essential for embryonic stem cell differentiation. Therefore, this study reveals a novel nonautophagic role of ATG5 in the regulation of c-Myc protein degradation.

During the past few decades, colorectal cancer (CRC) incidence and mortality have significantly increased, and CRC has become the leading cause of cancer-related death worldwide. Thus, exploring novel effective therapies for CRC is imperative. In this study, we investigated the effect of oncolytic adenovirus CD55-Smad4 on CRC cell growth. Cell viability assay, animal experiments, flow cytometric analysis, cell migration, and invasion assays, and Western blotting were used to detect the proliferation, apoptosis, migration, and invasion of CRC cells. The oncolytic adenovirus CD55-Smad4 was successfully constructed and effectively suppressed CRC cell proliferation in vivo and in vitro. Notably, CD55-Smad4 activated the caspase signaling pathway, inducing the apoptosis of CRC cells. Additionally, the generated oncolytic adenovirus significantly suppressed migration and invasion of CRC cells by overexpressing Smad4 and inhibiting Wnt/&beta, catenin/epithelial-mesenchymal transition (EMT) signaling pathway. Moreover, CRC cells treated with CD55-Smad4 formed less and smaller spheroid colonies in serum-free culture than cells in control groups, suggesting that CD55-Smad4 suppressed the stemness of CRC cells by inhibiting the Wnt/&beta, catenin pathway. Together, the results of this study provide valuable information for the development of a novel strategy for cancer-targeting gene-virotherapy and provide a deeper understanding of the critical significance of Smad4 in gene therapy of CRC.

A recently developed humanized mouse has been used to assess the immune response evoked against the isolated attenuated C9 parasite clone (C9-M; carrying a single insertion disrupting the open reading frame (ORF) of PF3D7_1305500) of

Histones are the main components in chromatin organization, and the protein levels of histones significantly affect chromatin assembly. However, how the protein levels of histones are regulated, especially whether and how histones are degraded, is largely unclear. Here, we found that histone H2B is mainly degraded through the proteasome-mediated pathway, and the lysine 120 site of H2B is essential for the K48-linked polyubiquitination and protein degradation of H2B. Moreover, our results further indicated that the degradation-impaired H2BK120R mutant shows an increased nucleolus localization, and inhibition of the proteasome results in an elevated nucleolus distribution of wild-type H2B, which is similar to that of H2BK120R mutants. More importantly, our in vitro data showed that only the nucleolus fractions can ubiquitinate and degrade the purified H2B, suggesting that the nucleolus, in addition to its canonical roles in the regulation of ribosome genesis and protein translation, is likely associated with H2B protein degradation. Therefore, these findings revealed a novel mechanism for the regulation of H2B protein degradation in which a nucleolus-associated proteasome pathway is involved.

Various fixation devices have been reported for stabilization of femoral neck fractures. Numerous studies on arthroplasty versus internal fixation devices in the treatment of femoral neck fractures have been performed, but the optimal approach for internal fixation has not been analyzed. A meta-analysis and system evaluation were performed to compare clinical effects. We searched PubMed, Embase, Cochrane Library, and Web of ScienceTM for randomized, controlled trials (RCTs) comparing multiple cannulated screws (MCS) with dynamic hip screws (DHS) and analyzed the failure rate of operations, the reoperation rate, and postoperative complications. Risk ratios (RRs) and mean differences from each trial were pooled using random effects or fixed effects models, depending on study heterogeneity. The analysis was performed using RevMan5.2. In this meta-analysis, 592 femoral neck fractures from 7 studies were assessed, and the meta-analysis results indicated significant differences in reoperation (RR 1.44, 95% confidence interval [CI] 1.10–1.88, P = 0.008) and failure rate (RR 2.28, 95% CI 1.10–4.72, P = 0.03), but no significant differences in the rate of postoperative complications between the MCS group and DHS group. DHS fixation has a larger skin incision and more soft tissue dissection, but it is associated with lower rates of fixation failure, reoperation, and overall rate of postoperative complications, and its use in elderly patients with osteoporosis is still recommended due to simplicity, efficacy, and high overall success rate. Multicenter RCTs with large samples are needed to better understand the comparative efficacy and safety of MCS and DHS in femoral neck fractures of restricted fracture type.

The copper mould and molten steel were modelled simultaneously by a three-dimensional (3D) model, which couples fluid flow, heat transfer and solidification. Thermal boundary conditions (e.g. air gap distribution, slag resistance, contact resistance) along casting direction and circumference direction were discussed and applied. The results of solid shell thickness distribution were compared with reference experimental data and reasonable agreements were found. The calculations indicate that, the shell thickness distribution along circumference in web was affected by the cross-section sizes. The uniform shell thickness distributions at narrow face and R corner were caused by the scouring of fluid flow. The heat transfer fluxes at hot face of mould were various at different locations.

A simple and organic solvent-free solid phase microextraction method using salt-assisted graphene oxide (GO) combined with ion chromatography-conductivity detection was developed for analysis of dimethylamine (DMA) and trimethylamine (TMA). The GO sheets were uniformly dispersed in aqueous solutions for efficient adsorption of DMA and TMA, and then aggregated with the addition of NaCl by electrostatic double layer attraction. DMA and TMA were eluted by using methanesulfonic acid and separated with GO aggregation by centrifuging. Finally, the analytes were injected into the ion chromatography system for analysis. The parameters influencing the extraction efficiency including sample pH, GO amount, adsorption time and NaCl concentration were investigated. Under the optimized conditions, the obtained limits of detection were 0.012 mg L−1 for DMA and 0.035 mg L−1 for TMA. The relative standard deviations were smaller than 3.8% for five successive measurements of 0.20 mg L−1 DMA and TMA. The proposed method was successfully applied to the analysis of DMA and TMA with recoveries ranging from 84 to 106% for tap water and river water samples.

Magnetic resonance imaging (MRI) is a powerful diagnostic technique that can penetrate deep into tissue providing excellent spatial resolution without the need for ionizing radiation or harmful radionuclides. However, diagnosing bacterial infections in vivo with clinical MRI is severely hampered by the lack of contrast agents with high relaxivity, targeting capabilities, and bacterial penetration and specificity. Here, we report the development of the first gadolinium (Gd)-based bacteria-specific targeting MRI contrast agent, probe 1, by conjugating neomycin, an aminoglycoside antibiotic, with Dotarem (Gd-DOTA, an FDA approved T1-weighted MRI contrast agent). The T1 relaxivity of probe 1 was found to be comparable to that of Gd-DOTA; additionally, probe 1-treated bacteria generated a significantly brighter T1-weighted MR signal than Gd-DOTA-treated bacteria. More importantly, in vitro cellular studies and preliminary in vivo MRI demonstrated probe 1 exhibits the ability to efficiently target bacteria over macrophage-like cells, indicating its great potential for high-resolution imaging of bacterial infections in vivo.

In a continuous casting process, mould powder is typically adopted to cover molten steel, which prevents liquid steel from oxidation by air, preserves heat for the top layer of liquid steel, lubricates the initial shell and so on. However, mould powder may deteriorate the quality of the final product if the entrapment of mould powder forms, which is usually caused by the instability of the steel/slag interface. In the current work, a model to predict the critical point of interfacial instability for liquid–liquid stratified flow was developed based on the Kelvin–Helmholtz instability. To prove the validity of the prediction model, a water model experiment was carried out in a rectangular container. In this experiment, oil and water were used to simulate slag and molten steel respectively. The results of the water model prove that the prediction model is correct. Applying the prediction model to a steel–slag system, the critical velocity of molten steel for mould powder entrapment is 0.463–0.541 m s− 1. Wh...

Eleven new oleanane-type triterpenoid saponins were isolated from the aerial parts of Schefflera kwangsiensis (1–11), together with nine esters (12–20) of known saponins. The structures of these compounds were elucidated on the basis of spectroscopic data analysis and chemical evidence. Furthermore, in in vitro assays, compounds 2, 3, 5, 7, 8, 11–13, 15, 17 and 18 (10 μM) exhibited moderate hepatoprotective activity against d -galactosamine-induced HL-7702 cell damage.

Six new taccalonolides, taccalonolides AT-AY (1–6), and two new withanolides, chantriolides D and E (7 and 8), together with ten known compounds (9–18), have been isolated from whole plants of Tacca chantrieri. The structures, including the absolute configurations of some of the compounds, were determined by spectroscopic and chemical methods. All compounds were evaluated for their in vitro cytotoxicity against five tumor cell lines. Compounds 9, 10, 13–15, and 17 exhibited cytotoxic activity, with IC50 values of 1.13–5.71 µM, while compound 7 showed selective cytotoxicity. The results indicated that taccalonolides with a six-membered lactone moiety located at C-15 and C-24 were devoid of cytotoxicity against five tumor cell lines (> 10 µM).

Profile control and flooding technique is an effective way to enhance the oil recovery of low permeability reservoir.Analyzing the relation between oil and water interface and determining injection volume under different concentration is the key to success in profile controlling and flooding in low permeability reservoir .The research is about SJT-B collosol of physicochemical property under normal pressure and temperature.We also carry on the study on measuring SJT-B collosol interfacial tension for a long time under different concentration.Besides, we conduct the plugging degree experiment by injecting SJT-B collosol with the concentration of 0.8% in different permeability core.The lower the core permeability, the higher the plugging degree. By optimizing the injection pattern we conduct the three-tube parallel profile control and flooding experiment in the low permeability heterogeneous core.It indicates that SJT-B collosol mainly access to high permeability layer and have an effective plugging effect .The absorbed liquid rate of medium permeability layer is increased apparently ,while low permeability layer is increased slightly.The SJT-B collosol of injection method has efficient effect on enhancing the oil recovery of low permeability reservoir in late water flooding.

Based on the panel data of 28 industries of China’s manufacturing industries from 2000 to 2013, through constructing a non-radial and double oriented DEA window model, we empirically estimated and analyzed the efficiency of carbon emissions reduction of manufacturing industries in China, and tested the threshold effect of environmental regulation on carbon emissions efficiency through panel threshold method. Results show that there are significant disparities among manufacturing industries in carbon emissions efficiency. The energy-intensive and resource-intensive industries have formed relative pollution industries, which have excessive energy input, excessive carbon dioxide emissions as well as efficiency loss for improper allocation of resources in the production process. Threshold test shows that there is a nonlinear relationship of ‘inverted U-curve’ between environmental regulation and carbon emissions efficiency. While we can improve the efficiency of carbon emissions by strengthening environmental regulation intensity, there is a ‘threshold effect’ in environmental regulation, firming that ‘Porter Hypothesis’ cannot set up without an important premise: a properly designed environmental regulation. We classified 28 manufacturing industries into five categories: weak regulation, mid-weak regulation, mid-strong regulation and strong regulation based on whether the emission intensity crosses the corresponding threshold value, and found that more than half of the relative pollution industries are in weak regulation and mid-weak regulation. Thus, we conclude that in order to improve the efficiency of carbon emissions reduction of manufacturing industry, we should give full play to the positive role of technology emissions reduction, scale economy, structural adjustment and optimization of energy structure.

Causative factors of multi-drug resistance tuberculosis (MDR-TB) were analyzed from iatrogenic angles, patients themselves, and society. Reviewed was the development of treatment strategies for MDR-TB from directly observed treatment short-course (DOTS) to DOTS-Plus. The history of Chinese medicine (CM) fighting TB and characteristics at the present stage were also analyzed. Authors pointed out that CM pays attention not only to killing pathogens and confirms the necessity of getting rid of pathogens, but also to cascade response caused by pathogens. It also regards the occurrence and development of MDR-TB as a whole by combining patients' conditions, climatic, geographic, psychological, and social factors. Authors believed that therapeutic principles under guidance of CM holistic view are of positive significance and inspiration in treating MDR-TB, and emphasized holistic view as basic strategies for treating MDR-TB, but not a single countermeasure.

To explore the effects of stand age on variation patterns of leaf C, N, P stoichiometric characteristics of Machilus pauhoi, two stands, i.e., 9 and 13 years old, were selected. The relationships between leaf nutrient contents (C, N and P) and diameters at breast height (DBH) of individual plants were analyzed. The data revealed that the individual variations of seedlings in M. pauhoi stands were strengthened with the stand development. The stand age had significant effects on leaf C, N, P contents and C:N ratio but not on C:P and N: P ratios. Specifically, the mean values of leaf C, N, P contents and N:P ratio in the 9-year-old stand were lower than those in the 13-year-old stand, whereas, inverse pattern of C:N and C:P ratios were found in the two stands. Furthermore, leaf N and P stoichiometry varied significantly within the stand. Specifically, leaf N and P contents, as well as their stoichiometric ratios, linearly correlated with DBH in the 9-year-old stand. On the contrary, leaf N and P stoichiometry showed quadratic correlation in 13-year-old stand (except leaf C:N which linearly correlated with DBH). Lastly, nutrient transfer rates of leaf N and P in the 9-year-old stand were higher than that in 13-year-old stand, and the discrepancies of leaf nutrient transfer strategy between growing and non-growing seasons were caused by the different growth phases and environmental conditions.

To effectively assess the reliability of aero-engine main fuel accelerated regulation system under poor failure statistics information, a fault tree analysis method based on interval model is presented. Firstly, according to main fuel accelerated regulation system principle and failure mechanism, the system fault tree model is established. Then interval number is introduced to describe the uncertainty of bottom event, and achieve the uncertainty transfer from bottom events to top event through constructing AND/OR gate interval operator. Finally, the failure probability estimation process of system top event is proposed based on double Monte Carlo method, and get the accurate failure interval of system response. At the same time, the importance measurement analysis of bottom events is conducted to identify the key failure events, which provides guidance for the main fuel accelerated regulation system in design and maintenance.

Racemic (±)-F18 (10-chloromethyl-11-demethyl-12-oxo-calanolide A), an analog of nature product (+)-calanolide A, is a new anti-HIV-1 nonnucleoside reverse transcript inhibitor (NNRTI). A successful enantioseparation of (±)-F18 offering (R)-F18 and (S)-F18 was achieved by a chiral stationary phase prepared HPLC. Their absolute configurations were determined by measurement of their electronic circular dichroisms combined with modem quantum-chemical calculations. Further investigation revealed that (R)-F18 and (S)-F18 shared a similar anti-HIV activities, however, (R)-F18 was more potent than (S)-F18 against wild-type virus, K101E mutation and P225H mutation pseudoviruses.

Tantalum nitride (TaN) compact with a Vickers hardness of 26 GPa is prepared by a high-pressure and hightemperature (HPHT) method. The crystal structure and atom occupations of WC-type TaN have been investigated by neutron powder diffraction, and the compressibility of WC-type TaN has been investigated by using in-situ high-pressure synchrotron x-ray diffraction. The third-order Birch–Murnaghan equation of state fitted to the x-ray diffraction pressure–volume (P – V) sets of data, collected up to 41 GPa, yields ambient pressure isothermal bulk moduli of B 0 = 369(2) GPa with pressure derivatives of for the WC-type TaN. The bulk modulus of WC-type TaN is not in good agreement with the previous result (B 0 = 351 GPa), which is close to the recent theoretical calculation result (B 0 = 378 GPa). An analysis of the experiment results shows that crystal structure of WC-type TaN can be viewed as alternate stacking of Ta and N layers along the c direction, and the covalent Ta–N bonds between Ta and N layers along the c axis in the crystal structure play an important role in the incompressibility and hardness of WC-type TaN.