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BACKGROUND Thromboelastography (TEG) is a novel blood viscoelasticity detection method revealing blood coagulation status and has been reported to be helpful in predicting clinical outcomes in patients with cardiovascular diseases (CVD). In this study, we aimed to investigate the association between TEG and CVD. MATERIAL AND METHODS A single-center case-control study was performed. Individuals who took TEG tests at Tongji Hospital in Wuhan, China from 2015 to 2019 were included. The nearest-neighbor Mahalanobis matching with replacement, within propensity score calipers of 0.25 was used to control the covariate imbalance between CVD patients and controls. Logistic regression analyses were conducted to assess the relationship between TEG and CVD. Subgroup and sensitivity analyses were performed to evaluate the robustness of the association between TEG and CVD. RESULTS After matching, a total of 151 participants were included in this study, with 83 patients having CVD (49 patients having coronary heart disease [CHD] and 34 patients having an ischemic stroke). By comparison, CHD patients had a significantly higher maximum amplitude (MA) (P=0.02) than controls. After multivariable adjustment, MA (OR 1.11, 95% CI 1.01-1.24, P=0.04) was independently associated with CHD. The association between MA and CHD remained robust across subgroups and in sensitivity analyses. CONCLUSIONS The current study suggests that MA is significantly associated with CHD. Enhanced platelet reactivity as described by high MA might be associated with risk of CHD. The exact role of MA in the measurement of CHD risk needs to be further examined in large-scale prospective cohort studies.

Exploration of the relation between the structural feature of oligomers and the ability of oligomers to damage the membrane has been an important subject in the study of the cytotoxic mechanism of amyloid proteins. In this work, we selected the hIAPP18-27 fragment as a model peptide and modified it by an alternating substitution of a d-amino acid for an l-amino acid in the hydrophilic N-terminal region, the hydrophobic C-terminal region, and the entire sequence. We prepared the oligomers using these peptides and investigated the effects of chain extension in different regions of the peptide on the ability of the oligomers to damage the membrane composed of POPC/POPG 4:1. We examined the morphology, structure, surface hydrophobicity, and packing compactness of the oligomers and monitored the changes in the structure and aggregation of the peptides upon interaction with the membrane. We found that the surface hydrophobicity and the disruptive ability of the oligomers are increased by an alternating l- and d-amino acid arrangement in the hydrophobic region of the peptide, while the packing compactness of the oligomers is increased and the disruptive ability of the oligomers decreased by an alternating l- and d-amino acid arrangement only in the hydrophilic region. The extension of the hydrophobic chain plays a significant role in the disruptive ability of the oligomers. Our results suggest that a positive relation between the surface hydrophobicity and the disruptive ability could be established only for the oligomers in which the peptide chains are flexible and loosely packed.

Summary Background The expression status and potential mechanistic involvement of microRNA (miR)-126-5p in hepatocellular carcinoma (HCC) are still elusive currently. Here we set out to address this issue both in cell lines and in patients’ tissues. Methods The relative expression levels of endogenous miR-126-5p and epidermal growth factor receptor (EGFR) were quantified by real-time polymerase chain reaction. Cell viability and proliferation were measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and clonogenic assays, respectively. Cell invasive and migrative capacities were determined by transwell and wound healing assays, respectively. The regulatory action of miR-126-5p on EGFR was interrogated by luciferase reporter assay. Translational level of EGFR was analyzed by Western blotting. Results MiR-126-5p was significantly down-regulated in both HCC patients’ tissues and cell lines. Forced expression of miR-126-5p greatly compromised cell viability, proliferation, invasion and migration, while miR-126-5p-specific inhibitor promoted these oncogenic phenotypes. MiR-126-5p mimics inhibited endogenous expression of EGFR and suppressed EGFR 3′-untranslated region-fused luciferase activity. Co-expression of EGFR in miR-126-5p-proficient cells completely restored cell migrative and invasive capacities, while co-transfection with EGFR siRNA significantly inhibited miR-126-5p inhibitor-induced cell invasion and migration. Conclusion MiR-126-5p was aberrantly decreased in HCC and subsequently relieved the suppression on EGFR expression, which consequently contributed to the tumor biology of HCC.

To evaluate the diagnostic efficacy of CBCT-MRI fused images for articular disc calcification of temporomandibular joint (TMJ). Twenty patients (24 TMJs) whose image examinations showed dense bodies in the TMJ space were included in the study. The locations of dense bodies evaluated by the three experts were used as a reference standard. Three oral and maxillofacial radiology residents evaluated whether the dense bodies were disc calcification or not, with a five-point scale for four sets of images (CBCT alone, MRI alone, both CBCT and MRI observed at a time, and CBCT-MRI fused images) randomly and independently. Each set of images was observed at least 1 week apart. A second evaluation was performed after 4 weeks. Intraclass correlation coefficients were calculated to assess the intra- and inter-observer agreement. The areas under the ROC curves (AUCs) were compared between the four image sets using Z test. Ten cases were determined as articular disc calcifications, and fourteen cases were recognized as loose bodies in the TMJ spaces. The average AUC index for the CBCT-MRI fused images was 0.95 and significantly higher than the other sets (p < 0.01). The intra- and inter-observer agreement in the CBCT-MRI fused images (0.90–0.91, 0.93) was excellent and higher than those in the other images. CBCT-MRI fused images can significantly improve the observers’ reliability and accuracy in determining articular disc calcification of the TMJ. The multimodality image fusion is feasible in detecting articular disc calcification of the TMJ which are hard to define by CBCT or MRI alone. It can be utilized especially for inexperienced residents to shorten the learning curve and improve diagnostic accuracy.

Three-dimensional (3D) hierarchical hollow pentagonal-cone-structured SnO2 nanorod array assemblies (HPCSNAs) were synthesized by a facile ultrasound-assisted hydrothermal approach in the absence o...

Relying on a cost-push input-output model for China, we estimate the exchange rate pass-through to both domestic prices and export prices at the industry level. Our empirical results indicate that the decline of the RMB price in the processing exports sector in response to an RMB appreciation is larger than that in the non-processing exports sector, which, in turn, is larger than the decline of the consumer price indexes. Our cross-sector analysis also suggests that exchange rate changes have the lowest impact on prices in capital- and technology-insensitive industries.

Background COVID-19 (coronavirus disease 2019) has caused a major epidemic worldwide; however, much is yet to be known about the epidemiology and evolution of the virus partly due to the scarcity of full-length SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) genomes reported. One reason is that the challenges underneath sequencing SARS-CoV-2 directly from clinical samples have not been completely tackled, i.e., sequencing samples with low viral load often results in insufficient viral reads for analyses. Methods We applied a novel multiplex PCR amplicon (amplicon)-based and hybrid capture (capture)-based sequencing, as well as ultra-high-throughput metatranscriptomic (meta) sequencing in retrieving complete genomes, inter-individual and intra-individual variations of SARS-CoV-2 from serials dilutions of a cultured isolate, and eight clinical samples covering a range of sample types and viral loads. We also examined and compared the sensitivity, accuracy, and other characteristics of these approaches in a comprehensive manner. Results We demonstrated that both amplicon and capture methods efficiently enriched SARS-CoV-2 content from clinical samples, while the enrichment efficiency of amplicon outran that of capture in more challenging samples. We found that capture was not as accurate as meta and amplicon in identifying between-sample variations, whereas amplicon method was not as accurate as the other two in investigating within-sample variations, suggesting amplicon sequencing was not suitable for studying virus-host interactions and viral transmission that heavily rely on intra-host dynamics. We illustrated that meta uncovered rich genetic information in the clinical samples besides SARS-CoV-2, providing references for clinical diagnostics and therapeutics. Taken all factors above and cost-effectiveness into consideration, we proposed guidance for how to choose sequencing strategy for SARS-CoV-2 under different situations. Conclusions This is, to the best of our knowledge, the first work systematically investigating inter- and intra-individual variations of SARS-CoV-2 using amplicon- and capture-based whole-genome sequencing, as well as the first comparative study among multiple approaches. Our work offers practical solutions for genome sequencing and analyses of SARS-CoV-2 and other emerging viruses.

The spatial distribution of the sediment nitrogen in ten typical estuaries of Lake Taihu was determined. A simple quantitative estimation model and principal component analysis (PCA) method were applied to find the source and major factors of estuarine sediment nitrogen loading. The average concentrations of total nitrogen (TN), organic nitrogen (Org-N), ammonium nitrogen and nitrate-nitrogen in the sediments of the ten estuaries were 1315.5, 1220.1, 82.53 and 6.45 mg/kg, with the organic fraction dominating. Results showed a significant difference for the TN concentration in sediments of different estuaries, which was mainly caused by geographical location, land use type and vegetation restoration measures. An important result was that sediment nitrogen in 80% of the estuaries was mainly originated from autochthonous algae and presettled organic matter, although there has been continuous pollution input from inflow rivers. The source estimation results found that the autochthonous aquaculture excretion, algae and hydrophyte debris and buried biodetritus accounted for 58.9% of the total nitrogen loading, which dominated the nitrogen sources compared with the pollution input. In addition, the PCA method was used to find that phosphorus loading and redox conditions were the major limiting factors affecting the distribution of inorganic and , respectively.

DBC1 has been characterized as a key regulator of physiological and pathophysiological activities, such as DNA damage, senescence and tumorigenesis. However, the mechanism by which the functional stability of DBC1 is regulated has yet to be elucidated. Here, we report that the ubiquitination-mediated degradation of DBC1 is dynamically regulated by the E3 ubiquitin ligase SIAH2 and deubiquitinase OTUD5 under hypoxic stress. Mechanistically, hypoxia promoted the competitive binding of SIAH2 with OTUD5 to DBC1, resulting in the ubiquitination and subsequent degradation of DBC1 through the ubiquitin–proteasome pathway. Siah2 knockout inhibited tumor cell proliferation and migration, which could be rescued by double knockout of Siah2/DBC1. Human tissue microarray analysis further revealed that the SIAH2/DBC1 axis was responsible for tumor progression under hypoxic stress. These findings define a key role of the hypoxia-mediated SIAH2-DBC1 pathway in the progression of human breast cancer and provide novel insights into the metastatic mechanism of breast cancer.

Biodegradable plastics (BPs) have been given high hopes to substitute conventional plastics, but their biodegradation requires strict conditions. BPs can accumulate for a long time in the environment and even derive biodegradable microplastics (BMPs), thus threatening wildlife and ecosystems. However, no efficient method is available for extracting BMPs from organisms' tissues. This study used multi-criteria decision-making (MCDM) methods to comprehensively evaluate and optimize extraction protocols of five BMPs from economic aquatic species. Digestion time, digestion efficiency, mass loss, cost, polymer integrity and size change were selected as evaluating indictors. According to the screening results of MCDM methods, Pepsin+H2O2 was selected as the optimal digestion method of BMPs because of its highest comprehensive score, which has high digestion efficiency (99.56%) and minimum plastic damage. Compared with olive oil, NaI is more suitable for separating BMPs from the digested residues. Furthermore, the combination of Pepsin+H2O2 digestion and NaI density separation was used to extract all five kinds of BMPs from the bivalve, crab, squid, and crayfish tissues, and all the recovery rates exceeded 80%. These results suggest that the optimal protocol is practicable to extract various BMPs from various aquatic organisms. This work was financially supported by the National Natural Science Foundation of China (42077384 and 21777068), the Fundamental Research Funds for the Central Universities (021114380176), Foundation of State Key Laboratory of Pollution Control and Resource Reuse (PCRRF2022), and Key Laboratory of Pesticide Environmental Assessment and Pollution Control, Ministry of Environmental Protection.

Traffic activities release large amounts of trace metal(loid)s in urban environments. However, the impact of vehicle operation-associated emissions on trace metal(loid) enrichment in road dust and the potential migration of these trace metal(loid)s to the surrounding environment remain unclear. We evaluated the contamination, sequential fraction, and bioaccessibility of trace metal(loid)s in urban environments by assessing their presence in road dust, garden vegetables, and tree tissues, including bark and aerial roots, at a traffic-training venue impacted by vehicle operation emissions and, finally, calculated the bioaccessibility-based health risk. The results indicated a significant accumulation of trace metal(loid)s in road dust, with the highest lead (Pb), cadmium (Cd), and antimony (Sb) concentrations in the garage entrance area due to higher vehicle volumes, frequent vehicle starts and stops, and lower speeds. Aerial roots exposed to hill start conditions exhibited the highest Pb, Zn, and Sb levels, potentially caused by high road dust resuspension, confirming that this tree tissue is an appropriate bioindicator. Sequential extraction revealed high percentages of carbonate-, Fe/Mn oxide-, and organic/sulphide-associated fractions of Pb, copper (Cu), and zinc (Zn) in road dust, while most Cd, Cr, Ni, and Sb occurred as residual fractions. According to the potential mobilizable fractions in sequential extraction, the in vitro gastrointestinal method could be more suitable than the physiologically based extraction test to evaluate the bioaccessibility-related risk of traffic-impacted road dust. The bioaccessibility-based health risk assessment of the road dust or soil confirmed no concern about noncarcinogenic risk, while the major risk originated from Pb although leaded gasoline was prohibited before the venue establishment. Furthermore, the cancer risks (CRs) analysis showed the probable occurrence of carcinogenic health effects from Cd and Ni to adults and from Cd, Cr, and Ni to children. Furthermore, the Cd and Pb concentrations in the edible leaves of cabbage and radish growing in gardens were higher than the recommended maximum value. This study focused on the health risks of road dust directly impacted by vehicle emissions and provides accurate predictions of trace metal(loid) contamination sources in the urban environment.

This paper mainly focuses on some notions of the lightlike rectifying curves and the centrodes in Minkowski 3-space. Some geometrical characteristics of the three types of lightlike curves are obtained. In addition, we obtain the conditions of the centrodes of the lightlike curves are the lightlike rectifying curves. Meanwhile, a detailed analysis between the N-type lightlike slant helices and the centrodes of lightlike curves is provided in this paper. We give the projections of the lightlike rectifying curves to the timelike planes.

Evidence of active tuberculosis (ATB) in patients with rheumatic diseases are research priorities but limited data from China have been reported. Research targeting patients not taking anti-TNF biologics are especially insufficient. We aimed to investigate the prevalence and risk factors of ATB in this at-risk population. We conducted a tertiary hospital-based, multi-center, cross-sectional study by using stratified multi-stage cluster sampling strategy to screen ATB in patients with rheumatic diseases. We estimated the prevalence of ATB in patients with rheumatic diseases and identified risk factors among those who were not taking anti-TNF biologic. A total of 13,550 patients with rheumatic diseases were enrolled, and the result showed the standardized prevalence of ATB according to the composition ratio of various types of rheumatic disease was 882/100000 (95% confidence interval (CI): 706-1057). Multivariable logistic regression analysis in patients not taking anti-TNF biologics showed that the independent risk factors of ATB were having systemic lupus erythematosus (SLE) (OR=2.722, 95% CI: 1.437-5.159, p=0.002), having Behcet's disease (BD) (OR= 5.261, 95% CI: 2.071-13.365, p

Objectives: To evaluate the diagnostic efficacy of CBCT–MRI fused image for anterior disc displacement and bone changes of temporomandibular joint (TMJ), which are the main imaging manifestations of temporomandibular disorders (TMD). Methods: Two hundred and thirty-one TMJs of 120 patients who were diagnosed with TMD were selected for the study. The anterior disc displacement, bone defect and bone hyperplasia evaluated by three experts were used as a reference standard. Three residents individually evaluated all the three sets of images, which were CBCT images, MRI images and CBCT-MRI fused images from individual CBCT and MRI images in a random order for the above-mentioned three imaging manifestations with a five-point scale. Each set of images was observed at least 1 week apart. A second evaluation was performed 4 weeks later. Intra- and interobserver agreements were assessed using the intraclass correlation coefficient (ICC). The areas under the ROC curves (AUCs) of the three image sets were compared with a Z test, and p < 0.05 was considered statistically significant. Results: One hundred and forty-five cases were determined as anterior disc displacement, 84 cases as bone defect and 40 cases as bone hyperplasia. The intra- and interobserver agreements in the CBCT-MRI fused image set (0.76–0.91) were good to excellent, and the diagnostic accuracy for bone changes was significantly higher than that of MRI image set (p＜0.05). Conclusions CBCT-MRI fused images can display the disc and surrounding bone structures simultaneously and significantly improve the observers’ reliability and diagnostic accuracy, especially for inexperienced residents.

Introduction：Osteoarthritis (OA) is a chronic musculoskeletal disorder of the movable joints. TCM has been widely used as complementary therapy for OA in Chinese. Traditional Chinese medicine (TCM) including Duhuojishi decoction, Shujing Huoxue decoction, Angelica Niantong decoction, Guilu Erxian glue et al are widely used in the clinical of osteoarthritis treatment. However there are very few large-scale studies about long-term effect of TCM on OA treatment. This study determined the long-term effects of TCM on reducing OA patients hospitalization risk.Material and methods: This study was a population-based retrospective cohort study. Patient data were collected from the claim-based Taiwan National Health Insurance Research Database from 2000 to 2012. We enrolled 67737 TCM treated cohort and 67737 non-TCM comparison of newly diagnosed OA patients. Propensity score matching was done on age, sex and possible confounders to ensure baseline comparability. Outcomes were medical utility, including hospitalization rate, emergency visits and direct medical expense. Logistic regression was conducted to compare the differences o between TCM and non-TCM groups. Subgroup analyses were also performed by age, gender, income and urbanization.Results: TCM group had an overall higher medical expense than non-TCM group. Although Logistic regression analysis results showed that there was no difference of emergency rate in TCM group and non-TCM group, TCM treatment reduced hospitalization rate of OA significantly.Conclusions: The usage of TCM was associated with a reduced risk of hospitalization of OA patients. TCM might play a complementary role in OA treatment.

Streptococcus mutans (S. mutans) is the most important oral pathogenic bacterial cause of dental caries. Here we investigated the abilities of probiotic lactobacillus strains of Lactobacillus curvatus (L. curvatus) BSF206 and Pediococcus pentosaceus (P. pentosaceus) AC1-2 to control S. mutans. Both probiotic strains are acid and bile salt tolerant and are resistant to hydrogen peroxide and lysozyme to promote their survival within the oral environment. In addition, both strains are highly hydrophobic and are also capable of engaging in electrostatic interactions. These properties enhance abilities of both strains to adhere to gingival epithelial cells and HT-29 for improved colonization of oral tissues, while also enabling these probiotics auto-aggregate and to form aggregates with S. mutans that both may prevent S. mutans from colonizing oral tissues and facilitate the clearance of the cariogenic bacteria from the mouth during swallowing of food and saliva. Furthermore, results presented herein revealed that L. curvatus BSF206 and P. pentosaceus AC1-2 effectively inhibited S. mutans activities (biofilm formation, secretion of extracellular matrix components, synthesis of water-insoluble glucans) and led to downregulation of expression of key S. mutans genes involved in biofilm production (gtfA, gtfB, ftf, brpA). Taken together, these results indicate that L. curvatus BSF206 and P. pentosaceus AC1-2 can inhibit S. mutans biofilm formation as a new strategy for preventing dental caries.

Since the mature green tomatoes have color similar to branches and leaves, some are shaded by branches and leaves, and overlapped by other tomatoes, the accurate detection and location of these tomatoes is rather difficult. This paper proposes to use the Mask R-CNN algorithm for the detection and segmentation of mature green tomatoes. A mobile robot is designed to collect images round-the-clock and with different conditions in the whole greenhouse, thus, to make sure the captured dataset are not only objects with the interest of users. After the training process, RestNet50-FPN is selected as the backbone network. Then, the feature map is trained through the region proposal network to generate the region of interest (ROI), and the ROIAlign bilinear interpolation is used to calculate the target region, such that the corresponding region in the feature map is pooled to a fixed size based on the position coordinates of the preselection box. Finally, the detection and segmentation of mature green tomatoes is realized by the parallel actions of ROI target categories, bounding box regression and mask. When the Intersection over Union is equal to 0.5, the performance of the trained model is the best. The experimental results show that the F1-Score of bounding box and mask region all achieve 92.0%. The image acquisition processes are fully unobservable, without any user preselection, which are a highly heterogenic mix, the selected Mask R-CNN algorithm could also accurately detect mature green tomatoes. The performance of this proposed model in a real greenhouse harvesting environment is also evaluated, thus facilitating the direct application in a tomato harvesting robot.

The mechanism of rheumatoid arthritis (RA) has been widely investigated, and studies on the use of arsenic trioxide (ATO) in the treatment of RA have been reported in recent years. However, the exact mechanism of action of ATO in RA remains unclear. This study explores alterations in the gut microbiota and metabolism during ATO treatment in a mouse model of RA and provides an integrative analysis of the biomechanism. The purpose of this study was to verify whether ATO can alleviate RA by altering the gut microbiota. In this study, the mice were randomly divided into four different groups: the normal control (NC) group, the collagen-induced arthritis (CIA) group, the ATO 1.0 mg/kg/day group, and the ATO 2.0 mg/kg/day group. Fecal samples were collected. Through 16S rDNA gene sequencing and metabolomic analysis, the effect of ATO on the composition and metabolites of gut microbiota in CIA mice was investigated. The results showed that compared with NC mice, CIA mice showed differences at both the phylum level (Firmicutes and Bacteroidetes) and the genus level (Muribaculaceae_unclassified and Alistipes). Meanwhile, many metabolites were significantly changed between the two groups, including benzoic acid and (s)-2-acetolactate. However, these alterations were partially reversed in ATO-treated CIA mice. These results indicated that ATO treatment modulated gut microbiota disorder and improved fecal metabolite abnormalities. In conclusion, this study provided important evidence for alterations of the gut microbiota and metabolites and the role of these alterations in a potential novel mechanism of ATO treatment in RA.

The intestine is not only the main accumulation organ of microplastics (MPs), but also the intestinal environment is very conductive to the release of additives in MPs. However, the kinetics of release process, influence factors, and the related effects on gut microbiota remain largely unknown. In this study, a mucosal-simulator of the human intestinal microbial ecosystem (M-SHIME) was used to investigate the influence of gut microbiota on the release of phthalates (PAEs) from MPs and the effects of MPs on the intestinal luminal microbiota and mucosal microbiota. We found that di-(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DBP), and dimethyl phthalate (DMP) were the dominant PAEs released in the gut. Gut microbiota accelerated the release of PAEs, with the time to reach the maximum release was shortened from 7 days to 2 days. Moreover, MPs induced differential effects on luminal microbiota and mucosal microbiota. Compared with mucosal microbiota, the luminal microbiota was more susceptible to the leaching of PAEs from MPs, as evidenced by more microbiota alterations. MPs also inhibited the metabolic activity of intestinal flora based on the reduced production of short chain fatty acids (SCFA). These effects were mainly contributed by the release of PAEs. Acidaminococcus and Morganella were simultaneously correlated to the release of PAEs and the inhibition of metabolic activity of intestinal microbiota and can be used as indicators for the intestinal exposure of MPs and additives.

Understanding the arsenic (As) enrichment mechanisms in the subsurface environment relies on a systematic investigation of As valence species and their partitioning with the Fe (oxyhydr)oxide phases in the subsoil profile. The present study explored the distribution, speciation, partitioning, and (im)mobilization of As associated with Fe in four subsoil cores (∼30 m depth) from Hong Kong using sequential chemical extraction and X-ray absorption near edge spectroscopy. The subsoil profiles exhibited relatively high concentrations of As at 26.1-982 mg/kg (median of 112 mg/kg), and the As was dominated by As(V) (85-96%) and primarily associated with the residual fraction (50.7-94.7%). A small amount of As (0.002-13.2 mg/kg) was easily mobilized from the four subsoil profiles, and a concentration of water-soluble As higher than 100 μg/L was observed for only some subsoil layers. The molar ratios of As:Fe in the oxalate-extractable Fe fraction ranged from 1.2 to 76.5 mmol/mol (median of 11.1 mmol/mol), revealing the participation of poorly crystalline Fe (oxyhydr)oxides in immobilizing most of the high geogenic As. The primary phases of ferric (oxyhydr)oxides were characterized as ferrihydrite (16-53%), lepidocrocite (0-32%), and goethite (0-62%), and these phases contributed to the sufficient ability of the subsoil to sequester 45.3-100% (median of 98.8%) of the exogenous As(V) (1.0 mg/L) in adsorption experiments. In contrast to As(V), exogenous As(III) showed a lower removal percentage (3.9-79.1%, median of 45.1%). The study revealed that the chemical speciation of As and Fe in the subsoil profiles is useful for predicting the immobilization of high geogenic As in the region, which is also helpful for the safe utilization of As-containing soil during land development worldwide.

AIDS, caused by HIV-1, is one of the most dangerous infectious diseases in the world. Therefore, it is necessary to develop new drugs with more potent bioactivities, less toxicity and higher tolerability for controlling the viral load, particularly by using the raw materials that are widely available. Agaricus blazei Murill (AbM), known in China as jisongrong, is of great importance as a food source and as a health-promoting supplement for immunomodulation. The polysaccharides of AbM exhibit various biological activities, such as regulating cellular immunity and providing anti-oxidative, anti-infective, and anti-inflammatory effects. At present, to our knowledge, no report has explored the chemically sulfated and anti-HIV-1 activity of AbM polysaccharides. Herein, the sulfated AbM polysaccharides with different sulfur contents were prepared by the chlorosulfonic acid-pyridine method. The characteristics of sulfated derivatives were established by the determination of the sulfur content, the relative molecular weight, and the Fourier-transform infrared spectroscopy. The anti-HIV activities of the sulfated AbM polysaccharides were evaluated by CCK-8 and the single-cycle pseudovirus infection (TZM-bl) assay. The sulfated AbM polysaccharides had strong antiviral properties, and the half-maximal inhibitory concentrations approached that of the positive control, azidothymidine. Sulfated modification of AbM polysaccharides can increase their anti-HIV pharmacological activity, which makes them promising alternative candidates as bioactive macromolecules for biomedical applications in HIV/AIDS.

Mapping biodiversity is essential for assessing conservation and ecosystem services in global terrestrial ecosystems. Compared with remotely sensed mapping of forest biodiversity, that of grassland plant diversity has been less studied, because of the small size of individual grass species and the inherent difficulty in identifying these species. The technological advances in unmanned aerial vehicle (UAV)-based or proximal imaging spectroscopy with high spatial resolution provide new approaches for mapping and assessing grassland plant diversity based on spectral diversity and functional trait diversity. However, relatively few studies have explored the relationships among spectral diversity, remote-sensing-estimated functional trait diversity, and species diversity in grassland ecosystems. In this study, we examined the links among spectral diversity, functional trait diversity, and species diversity in a semi-arid grassland monoculture experimental site. The results showed that (1) different grassland plant species harbored different functional traits or trait combinations (functional trait diversity), leading to different spectral patterns (spectral diversity). (2) The spectral diversity of grassland plant species increased gradually from the visible (VIR, 400–700 nm) to the near-infrared (NIR, 700–1100 nm) region, and to the short-wave infrared (SWIR, 1100–2400 nm) region. (3) As the species richness increased, the functional traits and spectral diversity increased in a nonlinear manner, finally tending to saturate. (4) Grassland plant species diversity could be accurately predicted using hyperspectral data (R2 = 0.73, p < 0.001) and remotely sensed functional traits (R2 = 0.66, p < 0.001) using cluster algorithms. This will enhance our understanding of the effect of biodiversity on ecosystem functions and support regional grassland biodiversity conservation.

To explore the genetic etiology for a fetus with congenital orofacial cleft.Single nucleotide polymorphism microarray (SNP array) was carried out on skin tissues sampled from the fetus following induced abortion for the detection of copy number variation (CNVs). Pathogenicity of the candidate gene was validated through experiment.SNP array revealed that the fetus has carried a hemizygous 9.23Mb deletion at Xq21.31-q22.1(91 063 807-100 293 555), which was inherited from its mother. The region contained 13 OMIM genes and 1 ncRNA coding gene(MIR548M). Inhibiting of the expression of the MIR548M gene in oral epithelial celllines has resulted in up-regulation of the expression of SUMO1 gene which was known to involve in the pathogenesis of orofacial cleft.Dosage insufficiency of the MIR548M gene may underlie the etiology of orofacial cleft in this fetus.

The objectives of the study were to comprehend the prevalence of hypertension (HTN) and prehypertension (PHT), awareness, treatment, and control of HTN and its distribution in urban, agricultural, pastoral, and semi‐agricultural/semi‐pastoral areas, and to explore the related factors of HTN among Mongolian adults in China. From August 2018 to August 2020, a multi‐stage stratified cluster random sampling method was conducted to investigate the prevalence of HTN among Mongolian adults aged ≥18 years living in China (n = 2558). Inclusion criteria for HTN were systolic blood pressure ≥ 140 mm Hg and/or diastolic blood pressure ≥ 90 mm Hg and/or had hypertensive history and/or taking antihypertensive drugs for HTN. The prevalence rates of HTN and PHT were 44.77% and 32.03%, respectively. The prevalence rates of PHT in urban, agricultural, pastoral, and semi‐agricultural/semi‐pastoral areas were 34.93%, 34.73%, 26.03%, and 33.44%, respectively, and the prevalence rates of HTN were 35.97%, 40.15%, 49.68%, and 48.07%, respectively. The awareness, treatment and control rates of HTN were 66.48%, 58.93%, and 16.48%, respectively. In this survey, the overweight, obesity, and central obesity rates were 34.30%, 30.67%, and 58.08%, respectively. Compared with Chinese adults ≥18 years, the prevalence rate of HTN among Mongolian adults in China aged ≥ 18 years was relatively high; the prevalence rate of PHT and HTN awareness, treatment, and control rates were similar. The prevalence of HTN and the rates of obesity and central obesity were higher in pastoral regions than in the other three types of regions, and the rate of overweight was highest in agricultural regions.

Severe pneumonia in children is a group of inflammatory diseases of respiratory tract caused by pathogenic microorganisms. Increasing evidence suggested the crucial effects of microRNA on inflammatory diseases. This study aimed to reveal the expression and role of miR-483-3p in the serum of children with severe pneumonia, and to explore the effect of miR-483-3p on the biological function of lipopolysaccharide (LPS)-induced MRC-5 cells. MRC-5 cells were disposed with LPS to construct an in vitro pneumonia cell model. The relative expression level of miR-483-3p was measured by qRT-PCR. ROC curve was used to evaluate the diagnostic value of miR-483-3p in severe pneumonia. The Kaplan-Meier curve was performed to test the characteristics of survival distribution of different miRNA classifications. Cell viability and apoptosis were performed by CCK-8 assay and flow cytometry. IL-1β, TNF-α, and IL-6 were detected by ELISA. Luciferase reporter gene assay and western blot analysis were performed to detect the interaction between miR-483-3p and IGF-1. The expression of serum miR-483-3p in severe pneumonia patients was higher than in controls. The AUC value of the ROC curve was 0.919, indicating that miR-483-3p had diagnostic value for severe pneumonia. The survival curve showed that patients with high expression of miR-483-3p had higher mortality. Cell viability and apoptosis assay showed that overexpression of miR-483-3p suppressed cell proliferation and promoted apoptosis. And upregulation of miR-483-3p promoted generation of inflammatory cytokines. Luciferase report gene assay and western blot assay both illustrated that IGF-1 might be the target gene of miR-483-3p. Serum miR-483-3p can be used as a biomarker for the diagnosis of severe pneumonia. High expression of miR-483-3p promoted the development of severe pneumonia.

Hollow urchin-like SnO2 nanospheres with tetragonal rutile structure were synthesized by a template-free hydrothermal route. The as-prepared products demonstrated a novel hollow urchin-like SnO2 nanosphere with the diameter of around 500 nm. It exhibited a high response and selectivity toward ethylene glycol at a lower heating voltage. The excellent ethylene glycol response was attributed to the hollow structure, the nanorods building blocks and the unique architecture structure.

Purpose The purpose of this paper is to examine the farmers’ income and to analyze the factors affecting the farmers’ income as well as rural life during the People’s Commune period. Design/methodology/approach The study’s data are drawn from unique account books of production team and a great deal of rural archives from the aspects of commune, production brigade and production team during the People’s Commune period. Findings The fate of the people’s commune is closely related to the income of its members. This study tries to explore the answers to “what determines members’ income” and “what influences their income,” which include the impact of the materialization on farmers’ income, the gender structure of the household labor force, the life cycle of the family and the population and so on. The main reason for farmers’ income differentiation is the difference in the demographic structure of the farmers, while the social system and traditional culture strengthen the role of this factor. Originality/value The biggest feature of the study is that it deeply explored the unique account books of production team from a micro-view, and studied the issue of People’s Commune from the level of farmers using the methods of historical textual research and mathematical analysis. This study is a supplement of the research on the family level which has long been lacked in the academic community.

Cerebral stroke is a fatal disease with increasing incidence. The study was to investigate the role and mechanism of Histone deacetylase 6 (HDAC6) on experimental stroke-induced brain injury. The recombinant shRNA-HDAC6 or scramble shRNA lentivirus was transfected to ICR mice. Then, the ischemia/reperfusion injury (I/RI) mice were constructed using middle cerebral artery occlusion (MCAO) method. Brain TTC staining was used to determine infarct areas. Serum levels of oxidative stress-related factors were detected by enzyme linked immunosorbnent assay (ELISA). Realtime-qPCR (RT-qPCR) and Western blot were used to respectively detect mRNA and protein levels. HDAC6 was up-regulated in brain I/RI mice (MCAO group), and down-regulated again in MCAO mice transfected with shRNA-HDAC6 (MCAO + shRNA group). The infarct area of the MCAO mice was increased, neurological scores were higher, and serum protein levels of 3-NT, 4-HNE and 8-OHdG were higher. HDAC6 interference attenuated above effects. Though protein levels of Nrf2 and HO-1 in cytoplasm increased slightly in MCAO group, they increased significantly by HDAC6 interference. The protein levels of Nrf2 in cytoblast decreased significantly in MCAO group, and increased markedly by HDAC6 interference. HDAC6 interference protected mice against experimental stroke-induced brain injury via Nrf2/HO-1 pathway.

We test the bilateral causal relationship between four types of international capital flows and the real effective exchange rate (REER) in China over the period 1998:Q1 to 2016:Q2 and examine whether the link is time varying. Parameter stability tests suggest that the relationship between capital flows and the RMB REER is time varying both in the short and the long run. Bootstrap rolling-window causality tests suggest bidirectional Granger causal relationships between the current account, portfolio investments and FDI, and the REER in several sub-periods, and a Granger-causal relationship from foreign exchange reserves to the REER in some sub-periods.

Sulfur cycling in freshwater ecosystems has been previously considered minor, and the direct evidence of its impacts on iron and phosphorus cycles in freshwater sediments remains unclear. In this study, mesocosms with amended acetate and various sulfate concentrations (1.5–3.0 mmol L−1) were set up to investigate sulfur cycling and its influences on iron-rich freshwater sediments. Acetate addition induced hypoxia and provided substrates, which stimulated the sulfur cycling with evidence of SO42− decline, ΣS2−, S0 increase and corresponding variations of sulfate-reducing bacteria (SRB) and sulfur-oxidizing bacteria. Meanwhile, the growth of iron-reducing bacteria (IRB) was suppressed, and lower Fe(II) release was correspondingly related to larger SRB abundance at higher sulfate level, indicating that microbial iron reduction might be blocked by SRB activities. However, continuous dissolution of Fe(III) oxides and generation of iron sulfides were observed, suggesting that sulfide-mediated chemical iron reduction (SCIR) became the dominant iron-reducing pathway, and Fe(II) was buried as iron sulfides instead of released to water column, which resulted in a transition of iron cycling into unidirectional SCIR. Consequently, continuous dissolution of Fe(III) oxides led to significant increase of PO43− concentration in the water column and sediment pore-water, revealing the phosphorus mobility in sediments derived from the SCIR process. To note, sustained accumulation of iron sulfides was observed even without ΣS2− presence, suggesting that ΣS2− precipitation occurred prior to diffusion. Thus, ΣS2−-missing sulfur cycling seemed “cryptic” in this study. To highlight, the transition of the iron-reducing pathway and resulting PO43− release can be induced even under current sulfate level of Lake Taihu, and elevated sulfate levels could significantly intensify SCIR and phosphorus mineralization. Thus, the stimulated iron deposition and the resulting phosphorus release derived from the sulfur cycling should be paid more attention to in the treatment of eutrophic freshwater ecosystems.

This study aims to monitor and assess the penetration and accumulation of titanium dioxide nanoparticles ( $TiO_{2}$ NPs) (25 nm and 60 nm) and the penetration of the $TiO_{2}$ NPs assisted by diode laser radiation (LR) in human normal endometrium (NE) and uterine leiomyoma (UL) tissues. In the 210 min ex vivo experiments, optical coherence tomography (OCT) and diffuse reflectance (DR) spectral measurement were used to study the changes in optical properties of tissues after $TiO_{2}$ NPs suspension administering. The results show that $TiO_{2}$ NPs make the OCT signal intensities and DR spectra of both NE and UL tissues increase with time, and larger NPs produce greater signal enhancement. In addition, there are significant differences between NE and UL tissues in terms of the values of attenuation coefficients. The experiment results indicate that the same size of the NPs penetrate faster in UL tissues than that in NE tissues, and 25 nm $TiO_{2}$ NPs allow larger penetration depth than 60 nm $TiO_{2}$ NPs in tissues. LR can remarkably increase the penetration of $TiO_{2}$ NPs in two types of tissues, especially in UL tissues. Analysis of attenuation coefficients and reflectance intensity reveals that the accumulation of the $TiO_{2}$ NPs in NE and UL tissues has great influence on the tissue optical properties.

Hierarchical nanoarrays SnO2 hollow microcubes were successfully synthesized by a simple one-pot template-free hydrothermal route without any substrates. The as-prepared products demonstrated novel hollow SnO2 microcubes with side length of 2–3 μm. Noticeably, the SnO2 cubic surfaces exhibited a hierarchical architecture of well-aligned nanorod arrays. The gas-sensing properties indicated that the nanoarrays SnO2 hollow microcubes possessed superior sensitivity towards ether at the heating voltage of 4.5 V. The formation and sensing mechanism of the nanoarrays SnO2 hollow microcubes were proposed in this paper.

Plasma must be heated by external heating for ignition in the future fusion reactor, ICRF heating is a favourable high-density plasma heating method since the fast wave launched from ICRF antenna can be transmitted to plasma core even in high-density plasma. While heating power increasing, the exposed antenna surface endures higher heat load. Faraday Shield (FS), as one of the key components, faces plasma and undertakes high heat load during plasma discharge. High stress and deformation on the FS is produced without removing the heating, which drastically reduces the antenna performance, even damages FS structure to threat RF antenna safety. To explore high-efficiency heat transfer enhancement technology to remove heat on the FS, one finite element analysis was used to analyse heat and temperature distribution on FS by different heat transfer ways, optimizing the FS structure. Based on the analysis results, several novel heat transfer enhancement way are proposed. Some workpieces with proposed heat transfer enhancement structure were designed and manufactured for test. Afterwards, two mock-ups with one quarter dimension of EAST ICRF antenna were manufactured without and with optimum heat transfer enhancement technology based on former test results, they were tested under same high heat load, significant results are obtained and presented in the paper, results are shown that heat transfer enhancement technology are drastically improved heat transfer performance of FS, which lay the foundation to high-power, steady-state operation ICRF antenna design in the future.

Extremely thin nanowires (NWs) would bend during the heteroepitaxial growth process. This phenomenon can increase the emission intensity due to the strain fields within bent NWs. Although the growth mechanism of NW heterostructures has been widely studied in theory, the theoretical studies are centered on growth on the surface of straight NWs, and the bending mechanism on extremely thin NWs has not been clearly explored. In this contribution, we have established an analytical thermodynamic theory to study the mechanism of bending induced by heteroepitaxial growth on the surface of thin NWs. It is found that the balance between surface energy and elastic strain energy plays a crucial role in the determination of the bending of NWs. The strain relaxation energy induces bending of NWs with small radii and high deposited amounts, while the size-dependent surface energy becomes more significant and restrains the bending of NWs with large radii and low deposited amounts. The established theoretical model not only explained the bending mechanism of NWs but also provided useful information to design the epitaxial growth on the surface with a nanoscale curvature.

Radiofrequency cavity is one of the most critical and complicated components in a cyclotron. Dee voltage of radiofrequency cavity accelerates charged particles to achieve required energy. Peak voltage of Dee is the key parameter of an radiofrequency cavity. Balanced Dee voltage is very important for effective beam cantering and beam extracting. An X-ray measurement has been made to calibrate and verify the peak voltage of Dee in a low-power ( 20 kW) test. The X-ray measurement for radiofrequency cavity was designed by means of bremsstrahlung. A suitable shielding cover was chosen for radiofrequency cavity and the X-ray measurement design was demonstrated according to the theory of photon transmission. Finally, the peak voltage of Dee was obtained at the power of 10-20 kW and the balance of Dee voltage was verified.

Castors are used to remediate heavy-metal-polluted soils due to their good ability to accumulate heavy metals. However, only limited studies addressed the interaction between heavy metals and castor seedling roots. In this study, the physiological response of castor seedling roots to Cd and Zn stress, and the change in trace elements in rhizosphere and non-rhizosphere soils were investigated. The results showed that, with an increase in Cd concentration, the accumulation of Zn in roots decreased by 20%, indicating a competition between Cd and Zn accumulation. The increase in Cd content enlarged the difference in nutrient contents at different depths: the amounts of P, Fe, and Mn were more in rhizosphere soils than in non-rhizosphere soils, while the amount of K showed an opposite trend. The addition of Cd and Zn stimulated root growth, but root activity was reduced. The addition of Cd and Zn affected the root cell morphology, including increases in the root cortex thickness and the root xylem area. The contents of the enzymes SOD, POD, and MDA increased with the addition of Cd and Zn, while the activity of CAT first increased and then decreased. There was no significant change in the soluble protein content. The decrease in IAA oxidase content, from 40.1% to 72.7%, was conducive to plant growth. To sum up, high contents of Cd and Zn in soils not only affect the root morphology and increase the gap in the contents of K, P, Fe, and Mn between rhizosphere and non-rhizosphere soils but also change the SOD, POD, MDA, and IAA contents in the root, so as to reduce the amount of root damage caused by the external environment.

Li, X.; Zhao, Y.; Han, R., and Wang, G., 2021. Fractionation and determinants of sediment nitrogen and phosphorus in the algae-dominated Moon Bay of Lake Taihu (China). Journal of Coastal Research, 37(3), 506–517. Coconut Creek (Florida), ISSN 0749-0208.Sediment nutrients are sensitive to environmental fluctuations. The frequent migration and transformation of sediment nutrients result in different fractions. Studying the relationships between favorable nutrient fractions and the benthic environment is critical for understanding the contributions of C, N, and P and their geochemical cycles. In total, nine sediment cores were collected for the study of spatiotemporal distributions of C, N, and P in sediments of Moon Bay, Lake Taihu (China). Pearson correlation and principal component analysis were performed to analyze the influence of environmental parameters and seasons on the concentration of sediment nutrient fractions. Results showed that the algal Moon Bay was phosphorus dominated, given the light total phosphorus loading (401.86 mg/kg). The great concentration gradient from sediment to overlying water (493 times) favored the phosphorus release. Dissolved oxygen, organic loading, and sediment depth showed a close relationship with the mineralization process, which was directly controlled by the reduction-oxidation potential. As the temperature increased, the mineralization could be enhanced. The lower total organic carbon to total nitrogen ratio in summer (16.37) than winter (30.5) verified the strong decomposition and mineralization with the help of active microorganisms. This study provides a reference to understand the influence of physicochemical parameters and primary producers on the C, N, and P geochemical cycles in sediments.

Persistent infections of high-risk human papillomaviruses (HPVs) are the leading cause of cervical cancers. We collected cervical exfoliated cell samples from females in Changsha city, Hunan Province and obtained 358 viral genomes of four major HPV types, including HPV 16 (n=82), 18 (n=35), 52 (n=121) and 58 (n=100). The lineage/sublineage distribution of the four HPVs confirmed previous epidemiological reports, with the predominant prevailing sublineage as A4 (50%), A1 (37%) and A3 (13%) for HPV16, A1 (83%) for HPV18, B2 (86%) for HPV52 and A1 (65%), A3 (19%) and A2 (12%) for HPV58. We also identified two potentially novel HPV18 sublineages, i.e. A6 and A7. Virus mutation analysis further revealed the presence of HPV16 and HPV58 strains associated with potentially high oncogenicity. These findings expanded our knowledge on the HPV genetic diversity in China, providing valuable evidence to facilitate HPV DNA screening, vaccine effectiveness evaluation and control strategy development.

BACKGROUND: Lycium barbarum polysaccharides (LBPs) belong to a very important class of biological macromolecules from Lycium barbarum berries in nature, and have received much attention due to their various biological activities. Since sulfated polysaccharides have antiviral activity in vitro, there is no published research on the sulfated modification of LBPs. RESULTS: The objective of this study was to investigate the feasibility of sulfated modification of LBPs and their potential application in inhibiting HIV-1. The LBPs with different molecular weight were prepared by fractional precipitation from crude LBP through aqueous extraction, ethanol precipitation and deproteinization. The purified LBPs (G1, G2 and G3) were sulfated by chlorosulfonic acid pyridine method to give rise to the sulfated LBPs (G1S1-G1S4, G2S1-G2S4 and G3S1-G3S4) with different degrees of substitution. The anti-HIV-1activities were evaluated by TD50 of the cytotoxicity and IC50 of inhibitory activity using the CCK-8 and Magi test with Azidothymidine (AZT) as positive control. The results showed that LBPs and sulfated LBPs showed non-toxicity with the TD50 >100 μg/mL. Compared with the LBPs, the inhibition of anti-HIV-1 activity of sulfated LBPs was increased significantly with the IC50 value from 0.0924-0.1206 μg/mL to 0.0206-0.0722 μg/mL. The G1S4 (Mw=2.13×104 Da and DS=1.12) showed excellent anti-HIV-1 activity with the IC50 value near to that of AZT (0.0200μg/mL), which would make it possible to become a candidate compound with anti-HIV-1 activity.CONCLUSION: The outcome of the study indicated that sulfated modification of LBPs was feasible and sulfated LBPs had good potential as an anti-HIV drug.

Abdominal aortic aneurysm (AAA) is a pathological state with permanent dilation, which indicates a fatal potential for aortic rupture. It has been reported that dexmedetomidine (Dex) and microRNA (miR)-21 are involved in the progression of AAA. Thus, the present study aimed to investigate the joint effects of these factors on AAA treatment. For this purpose, rat models of AAA were established with enzyme perfusion and the rats were then injected with Dex. Alterations in the abdominal aorta in rats with AAA were recorded. miR-21 expression in the rats with AAA was determined. Inflammatory factor expression was detected by western blot analysis. Subsequently, a dual-luciferase reporter gene assay was performed to verify the targeting association between miR-21 and programmed cell death protein 4 (PDCD4). Additionally, AAA-related indices and inflammatory responses were examined by an injection of a combination of antagomiR (ant)-miR-21 and Dex or lentivirus-PDCD4-short hairpin RNA. It was found that Dex markedly alleviated the development of AAA and downregulated the expression of inflammatory factors and matrix metalloproteinase in rats with AAA. The high expression of miR-21, which targets PDCD4, was observed in the rats with AAA. However, ant-miR-21 induced AAA development and inflammatory responses. Additionally, the inhibition of PDCD4 reduced AAA development and inflammatory responses. On the whole, the present study demonstrates that Dex inhibits AAA development by downregulating the miR-21/PCDP4 axis. The findings of the present study may provide novel insight for the treatment of AAA. These findings may provide a reference for the future treatment of AAA and may provide theoretical guidance for the early prevention and development of AAA.

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To assess the impact of antibiotic pollution to the ecosystem in urban water, the occurrence, seasonal, and spatial distributions, potential sources, and ecological risks of 18 targeted antibiotics in urban river, Pearl River located in Guangzhou city, were investigated. Surface water samples were sampled from 24 sites in Guangzhou center of Pearl River during dry and wet seasons. The results indicated that the concentrations of antibiotic residues were at the nanogram per liter level, except sulfamethazine (SMD) (μg/L). Sulfonamides (SAs) were the dominant antibiotics, contributing 60.4-65.0% to the total antibiotics. The concentrations of SAs, fluoroquinolones (QUs), macrolides (MLs), tetracyclines (TCs), and lincosamides (LCs) were higher in dry season than those in wet season at most sampling sites, which possibly resulted from the dilution effect of heavy rainfall. The concentrations of the antibiotic residues in Guangzhou were comparable or higher than other urban rivers. The calculation on risk quotients indicated that erythromycin-H2O (ETM-H2O) and tetracycline (TC) were of high risks. The source identification by the Pearson correlation analysis and principal component analysis-multiple linear regression (PCA-MLR) method suggested that municipal wastewater treatment plants were primary sources of antibiotics. These results would provide important information for the environmental protect.

Laminar airfoil has extensive application prospect in the civil aviation area as its low drag characteristic. However, the laminar flow is too sensitive to be disturbed and then laminar-turbulent transition location will move forward, which results in a significant increase in drag. Therefore, it is meaningful to obtain the aerodynamic characteristics of laminar airfoil both under natural transition and disturbed transition conditions. This paper focuses on the aerodynamic characteristics of a laminar airfoil named NACA65(1)412. Firstly, numerical simulations of natural transition of the airfoil flow at various angles of attack were carried out using γ-Reθ model. Secondly, forced transition simulations were taken to imitate the disturbed airfoil flow using k-ω SST model. Results show that, the transition location has a great influence on the aerodynamic characteristics of laminar airfoil, especially on the drag. For the natural transition, as the angle of attack increasing, the natural transition location on the upper surface moves upstream while the one on the lower surface moves the opposite. The upper-surface transition location moves upstream rapidly after the 4° angle of attack. For the forced transition, the drag increases approximately linearly with the transition location for both the upper and lower surface, but the upper-surface behaves much more significant. The lift changes little with the movement of transition locations.

Text abstracting is widely used in search engine, text database, information filtering. In the text extraction method, the mathematical model is usually established first and extracted by the model, but this method is not effective in solving nonlinear problems. Support vector machine (SVM), based on statistical learning theory, converts a certain amount of text into vectorized training text data for extraction. This paper adopts support vector machine (SVM) to study text extraction in telecommunication field, and we obtained good results.

Direct evidence of the algae bloom in eutrophic freshwater lakes on sulfur cycle and the subsequent iron oxide reduction and the iron oxides-bound phosphate (Fe-P) release in sediments is lacking. In this study, microcosms experiment was carried out to investigate the dynamic variations of S, Fe and P species in the water column and sediments as well as the sulfate reducing bacteria (SRB) abundance variation in the sediments during algae decomposition. The sulfate reduction was stimulated by the algae decomposition, which resulted in dramatic sulfate decline, sulfide increase and SRB growth. In addition, large amounts of acid volatile sulfide (AVS), pyrite sulfur (Pyrite-S) and elemental sulfur (S0) accumulated in the sediment. In particular, the contents of sedimentary Fe(II) and Pyrite-S in surface sediments continuously accumulated until the end of the experiment. Moreover, the terminal Fe-P content reduced by 35.4% compared with the initial concentration at high algae density group. These results suggested the irreversible reduction of iron oxides and revealed iron chemical reduction mediated by sulfide during algae decomposition. In addition, the connection of sulfur-iron cycle and the significant promotion of Fe-P mobilization in sediments was established, which should be paid more attention in the eutrophic freshwater ecosystems.

The trajectory tracking precision of quadrotor aircraft is affected by external interference and system parameter perturbation. In order to solve the problems, a robust control method based on improved high-order extended state observer(ESO) and block backstepping sliding mode is proposed in this paper. At first, the system model of quadrotor aircraft is divided into two subsystems of position part and attitude part. Then, the perturbations and external disturbances of the system are the uncertainty term, and an improved ESO is designed to estimate them. The estimated value is compensated timely in controller, thus the position trajectory tracking accuracy is improved efficiency. Moreover, the system structural with strong coupling characteristic, thus a robust controller is designed based on the block backstepping and sliding mode method for the attitude part. The block backstepping is contributed to solve the limitation of the traditional sliding mode method under the unmatched condition effectively, so the control attitude of the system is ensured. Meanwhile, the stability of the system is proved by Lyapunov stability theory. The simulation results demonstrate that the effectiveness of the method in this paper, and it can realize the accurate trajectory tracking for quadrotor.

The offshore wind energy (OWE) pile foundation is mainly a large diameter open-ended single pile in shallow water, which has to bear long-term horizontal cyclic loads such as wind and waves during OWE project lifetime. Under the complex cyclic loads, the stress and displacement fields of the pile-soil system change continuously, which affects the dynamic characteristics of the pile foundation. Within the service life of the pile foundation, the pile-soil system has irreversible cumulative deformation, which further causes damage to the whole structure. Therefore, it is important to examine the overall dynamic characteristics of wind power foundation under high cycle. In this paper, in the dry sand foundation, taking the Burbo Bank 3.6 MW offshore turbine-foundation structure as the prototype, the horizontal cyclic loading model tests of the wind power pile foundation with the scale of 1:50 were carried out. Considering the factors such as loading frequency and cyclic load ratio, the horizontal dynamic characteristics of the whole OWE pile foundation are studied. The comparison results between the maximum bending moment of pile and the fitting formula are discussed. In conclusion, moment of OWE pile shaft is corresponding to the loading frequency (f = 9 HZ) and loading cycles by fitting formulas. The fatigue damage of the OWE pile does not occurs with low frequencies in high cycles.