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Drawing on the core idea of Propensity Score Matching, this study proposes a new concept named Historical Traffic Violation Propensity to describe the driver's historical traffic violations, and combines the new concept with an improved mutual information-based feature selection algorithm to construct a method for screening key traffic violations from the perspective of expressing driver's accident risk. The validation analysis based on the real data collected in Shenzhen demonstrated that drivers' state of Historical Traffic Violation Propensity on 19 key traffic violations screened have a stronger predictive ability of their subsequent accidents compared to the level in existing research. The positive state of Historical Traffic Violation Propensity on 'Drinking', 'Parking in dangerous areas', 'Wrong use of turn lights', 'Violating prohibited and restricted traffic regulations', and 'Disobeying prohibition sign' will increase the probability of a driver's subsequent accident by more than 1.7 times. The research provides directions to more efficiently and accurately capture the driver's accident risk through historical traffic violations, which is valuable for identifying high-risk drivers as well as the key psychological or physical risk factors that manifest in daily driving activities and lead to subsequent accidents.
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Condução de Veículo , Humanos , Acidentes de Trânsito/prevenção & controle , Fatores de Risco , Comportamento PerigosoRESUMO
Accurately and quickly mining the hidden information in railway dangerous goods transportation (RDGT) accident reports has great significance for its safety management. In this paper, a data mining method Logistics-DT-TFP is proposed for analysing the causes of RDGT accidents. Firstly, analyse the transportation process, extract the cause of the accident, and classify the severity of the accident. Then, using ordered multi-classification Logistic regression for correlation calculation, qualitatively judge and quantitatively analyse the relationship between each cause and the severity of the accident. The feature tags of the Decision Tree (DT) are screened, the C5.0 algorithm is used to obtain the accident coupling rules. Next, the FP-Growth algorithm is used to mine frequent itemsets, and TOP-K is used to improve it and output effective association rules with the degree of lift as the indicator, which avoids repeated traversal of the database, shortens the time complexity, and reduces the impact of the minimum support setting on the calculation results. The degree of lift among the causes in the coupling chain is calculated as a complement to the extraction of coupling rules. Finally, based on the analysis and mining results of case study, the management strategies for railway dangerous goods are proposed.
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Acidentes de Trânsito , Meios de Transporte , Humanos , Causalidade , Mineração de Dados/métodos , AlgoritmosRESUMO
This article reviews the research progress of rehabilitation treatment and nursing care of patients with neurogenic bladder after spinal cord injury, in order to provide reference for the rehabilitation treatment and nursing care of patients. We reviewed recent medical literature on patients with neurogenic bladder, focusing on neurogenic bladder caused by spinal cord injury. We analyzed 30 recent of publications in patients with neurogenic bladder after spinal cord injury, in addition to reviewing and evaluating the commonly used rehabilitation nursing methods for neurogenic bladder. Psychological counseling is a vital aspect which cannot be neglected in the process of neurogenic bladder rehabilitation. Hitherto, the commonly used drug and surgical treatments may have negatively impacted the mental health of patients in varying degrees. However, in clinical practice, applying intermittent catheterization in patients who have neurogenic bladder with spinal cord injury may help improve patients' life quality, mitigate psychological burden, and reduce negative emotions.
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Antibiotics have been widely used for improving human and animal health and well-being for many decades. However, the enormous antibiotic usage in agriculture especially for livestock leads to considerable quantities of antibiotic residues in associated food products and can reach potentially hazardous levels for consumers. Therefore, timely detection and systematical surveillance on residual antibiotics in food materials are of significance to minimize the negative impact caused by such unwanted antibiotic leftovers. To this end, we constructed a cloud-platform-based system (ARSCP) for comprehensive surveillance of antibiotic residues in food materials. With the system, we collected 126,560 samples from 68 chicken farms across China and detected the antibiotic residues using a rapid detection colorimetric commercial (Explorer 2.0) kit and UPLC-MS/MS. Only 108 (0.085 %) of the samples contained residual antibiotics exceeding the MRLs and all data were subjected to ARSCP system to provide a landscape of antibiotic residues in China. As a proof-of-concept, we provided an overview of residual antibiotics based on data from China, but the system is generally applicable to track and monitor the antibiotic residues globally when the data from other countries are incorporated. We used the combined Explorer 2.0 and MS data to construct ARSCP, an antimicrobial residue surveillance cloud platform for raw chicken samples. ARSCP can be used for rapid detection and real-time monitoring of antibiotic residues in animal food and provides both data management and risk warning functions. This system provides a solution to improve the management of facilities that must monitor antibiotic MRLs in food animal products that can reduce the pollution of antibiotics to the environment.
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Anti-Infecciosos , Computação em Nuvem , Animais , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Antibacterianos , Ração Animal , Progressão da DoençaRESUMO
The extensive use of tetracycline antibiotics has led to the widespread presence of tetracycline-resistance genes in Gram-negative bacteria and this poses serious threats to human and animal health. In our previous study, we reported a method for rapid detection of Tet(X)-producers using MALDI-TOF MS. However, there have been multiple machineries involved in tetracycline resistance including efflux pump, and ribosomal protection protein. Our previous demonstrated the limitation in probing the non-Tet(X)-producing tetracycline-resistant strains. In this regard, we further developed a MALDI-TOF MS method to detect and differentiate Tet(X)-producers and non-Tet(X)-producing tetracycline-resistant strains. Test strains were incubated with tigecycline and oxytetracycline in separate tubes for 3 h and then analyzed spectral peaks of tigecycline, oxytetracycline, and their metabolite. Strains were distinguished using MS ratio for [metabolite/(metabolite+ tigecycline or oxytetracycline)]. Four control strains and 319 test strains were analyzed and the sensitivity was 98.90% and specificity was 98.34%. This was consistent with the results obtained from LC-MS/MS analysis. Interestingly, we also found that the reactive oxygen species (ROS) produced by tetracycline-susceptible strains were able to promote the degradation of oxytetracycline. Overall, the MALDITet(X)-plus test represents a rapid and reliable method to detect Tet(X)-producers, non-Tet(X)-producing tetracycline-resistant strains, and tetracycline-susceptible strains.
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Oxitetraciclina , Tetraciclina , Animais , Antibacterianos/farmacologia , Cromatografia Líquida , Bactérias Gram-Negativas/genética , Testes de Sensibilidade Microbiana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem , Tetraciclina/farmacologia , Tigeciclina/farmacologiaRESUMO
Currently, the road safety performance of a national- or province-level is absorbing much attention from practitioners and academics. A variety of models based on Data Envelopment Analysis (DEA) have been presented to appraise road safety performance in previous literature. However, the main weakness of these methods is that the decision-maker's psychological behavior is neglected. Besides, Cross Efficiency Method (CEM) adopts the weighted average to aggregate the cross efficiencies which may lead to information loss. To address these limitations, a hybrid road safety evaluation model was constructed by integrating CEM, regret theory, and Weighted Aggregated Sum Product Assessment (WASPAS) to appraise the road safety performance of Chinese provinces. In the presented model, regret theory is employed to depict the psychological behavior of the decision-maker. Then entropy weight method is utilized to calculate the weight of self-evaluation and peer-evaluation. To reduce information loss, WASPAS is adopted to fuse the cross efficiencies and derive the ranking of decision-making units. Finally, the presented model is employed to assess the road safety efficiency in the province of mainland China. The results show that the mean of road safety efficiency score for the eastern, central, and western areas is gradually decreasing. Furthermore, the outcomes of a comparative analysis represent that the results obtained by the proposed model outperform the CEM and DEA road safety model.
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Acidentes de Trânsito , Emoções , Acidentes de Trânsito/prevenção & controle , China , HumanosRESUMO
Essential decision-making tasks such as power management in future vehicles will benefit from the development of artificial intelligence technology for safe and energy-efficient operations. To develop the technique of using neural network and deep learning in energy management of the plug-in hybrid vehicle and evaluate its advantage, this article proposes a new adaptive learning network that incorporates a deep deterministic policy gradient (DDPG) network with an adaptive neuro-fuzzy inference system (ANFIS) network. First, the ANFIS network is built using a new global K-fold fuzzy learning (GKFL) method for real-time implementation of the offline dynamic programming result. Then, the DDPG network is developed to regulate the input of the ANFIS network with the real-world reinforcement signal. The ANFIS and DDPG networks are integrated to maximize the control utility (CU), which is a function of the vehicle's energy efficiency and the battery state-of-charge. Experimental studies are conducted to testify the performance and robustness of the DDPG-ANFIS network. It has shown that the studied vehicle with the DDPG-ANFIS network achieves 8% higher CU than using the MATLAB ANFIS toolbox on the studied vehicle. In five simulated real-world driving conditions, the DDPG-ANFIS network increased the maximum mean CU value by 138% over the ANFIS-only network and 5% over the DDPG-only network.
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Aberrant alterations of rearranged during transfection (RET) have been identified as actionable drivers of multiple cancers, including thyroid carcinoma and lung cancer. Currently, several approved multikinase inhibitors such as vandetanib and cabozantinib demonstrate clinical activity in patients with RET-rearranged or RET-mutant cancers. However, the observed response rates are only modest and the 'off-target' toxicities resulted from the inhibition of other kinases is also a concern. Herein, we designed and synthesized a series of RET inhibitors based on the structure of selective RET inhibitor BLU-667 and investigated their biological activities. We identified compound 9 as a novel potent and selective RET inhibitor with improved drug-like properties. Compound 9 exhibits a selective inhibitory profile with an inhibitory concentration 50 (IC50) of 1.29 nM for RET and 1.97 (RET V804M) or 0.99 (RET M918T) for mutant RETs. The proliferation of Ba/F3 cells transformed with NSCLC related KIF5B-RET fusion was effectively suppressed by compound 9 (IC50 = 19 nM). Additionally, compound 9 displayed less 'off-target' effects than BLU-667. In mouse xenograft models, compound 9 repressed tumor growth driven by KIF5B-RET-Ba/F3 cells in a dose-dependent manner. Based on its exceptional kinase selectivity, good potency and high exposure in tumor tissues, compound 9 represents a promising lead for the discovery of RET directed therapeutic agents and the study of RET-driven tumor biology.
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Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-ret/metabolismo , Relação Estrutura-AtividadeRESUMO
Antimicrobial resistance is recognized as one of the major global health challenges of the 21st century. Synergistic combinations for antimicrobial therapies can be a good strategy for the treatment of multidrug resistant infections. We examined the ability of a group of 29 plant essential oils as substances which enhance the antibiotic activity. We used a modified well diffusion method to establish a high-throughput screening method for easy and rapid identification of high-level enhancement combinations against bacteria. We found that 25 essential oils possessed antibacterial activity against Escherichia Coli ATCC 25922 and methicillin-resistant Staphylococcus aureus (MRSA) 43300 with MICs that ranged from 0.01% to 2.5% v/v. We examined 319 (11 × 29) combinations in a checkerboard assay with E. Coli ATCC 25922 and MRSA 43300, and the result showed that high-level enhancement combinations were 48 and 44, low-level enhancement combinations were 214 and 211, and no effects combinations were 57 and 64, respectively. For further verification we randomly chose six combinations that included orange and Petitgrain essential oils in a standard time-killing assay. The results are in great agreement with those of the well diffusion assays. Therefore, the modified diffusion method was a rapid and effective method to screen high-level enhancement combinations of antibiotics and essential oils.
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Telework has been promoted for decades as one of the traffic demand management policies to alleviate congestion during peak periods and reduce work-related trips, along with other benefits. However, less clear is the role played by life stages (i.e., gender, marital status and parenthood) on telework behavior. This study investigated to which extent telework frequency associated with life stages, and how these associations could be explained based on the work-life conflict perspective. Representative data were obtained from German Microcensus 2010 (N = 188,081 participants). The outcome variable was measured as ordered telework participation levels (i.e., never, infrequently and frequently). After testing for multicollinearity, a zero-inflated ordered probit regression model was applied to assess the associations between telework and family-life stages, while adjusting for individual, household, job-related and environmental characteristics. Results suggest that life stages associate with telework behavior in a complex way. Three patterns have been distinguished. Specifically, irrespective of gender and marital status, parents are less likely to telework compared to those without children. Regarding individuals without children, single individuals are more likely to telework than married ones, and males more likely than females. In contrast, for individuals with children, the partnered parents are more likely to telework than single parents, and females more likely than males. Our findings suggest that as the most important feature in family-life stages, children play a vital role in telework behavior. It not only increases both work-to-family conflict and family-to-work conflict, but also triggers housework re-division within couples and aggravates gender differences. Policies that support formal childcare resources could relieve the family-to-work conflict and encourage people to work at home.
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Macrophomina phaseolina, causative agent of the charcoal rot disease, impacts over 500 plant species, causing devastating crop failures worldwide. Due to the lack of effective management approach, charcoal rot can result in serious loss, especially during years with hot and dry summers. This study aims to evaluate the effectiveness of using the RNA interference (RNAi) mechanism to suppress the growth of M. phaseolina, through exogenous application of small interfering RNA (siRNA) targeting one of the chitin synthase (MpCHS) genes in the M. phaseolina genome. Since chitin is one of the main components in the fungal cell wall, we hypothesize that suppressing the expression of MpCHS through RNAi will negatively affect the growth of the fungus, which may result in reduced virulence toward the host. Of the seven candidate MpCHS genes assessed, MpCHS6 showed consistent expression in plate-grown fungus and in infected plant tissue and was chosen as the target for RNAi knockdown. Two siRNAs were designed to target MpCHS6 and tested through in vitro application in M. phaseolina culture. Both siRNAs suppressed growth of the fungus at multiple time points and under varied environmental conditions. More importantly, the growth suppression was well correlated with down-regulation of the MpCHS6 gene. These results indicate that exogenous siRNAs can suppress gene expression in M. phaseolina even when applied in vitro. In addition, targeting a MpCHS gene may provide an effective way to control the fungal growth. Our study provides firsthand knowledge on RNAi in M. phaseolina, which benefits not only basic research that focuses on understanding gene function in this species but also application of RNAi-based technology in disease control in the future.
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Ascomicetos/crescimento & desenvolvimento , Quitina Sintase/genética , RNA Interferente Pequeno/genética , Ascomicetos/genética , Ascomicetos/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Melaninas/metabolismo , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Doenças das Plantas/microbiologia , Interferência de RNARESUMO
BACKGROUND: Catechins, caffeine, and theanine as three important metabolites in the tea leaves play essential roles in the formation of specific taste and shows potential health benefits to humans. However, the knowledge on the dynamic changes of these metabolites content over seasons, as well as the candidate regulatory factors, remains largely undetermined. RESULTS: An integrated transcriptomic and metabolomic approach was used to analyze the dynamic changes of three mainly metabolites including catechins, caffeine, and theanine, and to explore the potential influencing factors associated with these dynamic changes over the course of seasons. We found that the catechins abundance was higher in Summer than that in Spring and Autumn, and the theanine abundance was significantly higher in Spring than that in Summer and Autumn, whereas caffeine exhibited no significant changes over three seasons. Transcriptomics analysis suggested that genes in photosynthesis pathway were significantly down-regulated which might in linkage to the formation of different phenotypes and metabolites content in the tea leaves of varied seasons. Fifty-six copies of nine genes in catechins biosynthesis, 30 copies of 10 genes in caffeine biosynthesis, and 12 copies of six genes in theanine biosynthesis were detected. The correlative analysis further presented that eight genes can be regulated by transcription factors, and highly correlated with the changes of metabolites abundance in tea-leaves. CONCLUSION: Sunshine intensity as a key factor can affect photosynthesis of tea plants, further affect the expression of major Transcription factors (TFs) and structural genes in, and finally resulted in the various amounts of catechins, caffeine and theaine in tea-leaves over three seasons. These findings provide new insights into abundance and influencing factors of metabolites of tea in different seasons, and further our understanding in the formation of flavor, nutrition and medicinal function.
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Cafeína/biossíntese , Camellia sinensis/metabolismo , Catequina/biossíntese , Glutamatos/biossíntese , Expressão Gênica , Metabolômica , Fenótipo , Folhas de Planta/metabolismo , Estações do Ano , Fatores de Transcrição/metabolismo , TranscriptomaRESUMO
BACKGROUND: The prognostic impact of microRNA (miRNA) expression levels in pancreatic cancer (PC) has been estimated for years, but the outcomes are controversial and heterogeneous. Therefore, we comprehensively reviewed the evidence collected on miRNA expression in PC to determine this effect. RESULTS: PC patients with high miR-21 (HR=2.61, 95%CI=1.68-4.04), miR-451a (HR=2.23, 95%CI=1.23-4.04) or miR-1290 (HR=1.43, 95%CI=1.04-1.95) levels in blood had significantly poorer OS (P<0.05). Furthermore, PC patients with high miR-10b (HR=1.73, 95%CI=1.09-2.76), miR-17-5p (HR=1.91, 95%CI=1.30-2.80), miR-21 (HR=1.90, 95%CI=1.61-2.25), miR-23a (HR=2.18, 95%CI=1.52-3.13), miR-155 (HR=2.22, 95%CI=1.27-3.88), miR-203 (HR=1.65, 95%CI=1.14-2.40), miR-221 (HR=1.72, 95%CI=1.08-2.74), miR-222 levels (HR=1.72, 95%CI=1.02-2.91) or low miR-29c (HR=1.39, 95%CI=1.08-1.79), miR-126 (HR=1.55, 95%CI=1.23-1.95), miR-218 (HR=2.62, 95%CI=1.41-4.88) levels in tissues had significantly shorter OS (P<0.05). CONCLUSIONS: In summary, blood miR-21, miR-451a, miR-1290 and tissue miR-10b, miR-17-5p, miR-21, miR-23a, miR-29c, miR-126, miR-155, miR-203, miR-218, miR-221, miR-222 had significant prognostic value. METHODS: We searched PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews to recognize eligible studies, and 57 studies comprising 5445 PC patients and 15 miRNAs were included to evaluate the associations between miRNA expression levels and overall survival (OS) up to June 1, 2019. Summary hazard ratios (HR) with 95% confidence intervals (CI) were calculated to assess the effect.
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MicroRNAs/sangue , Neoplasias Pancreáticas , Biomarcadores Tumorais/sangue , Humanos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Prognóstico , Sensibilidade e EspecificidadeRESUMO
A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical conditions, underscoring the enhanced reactivity provided by the combination of transition metal catalysis and electrochemistry.
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Aim: Prostate cancer (PCa) is the sixth leading cause of cancer-related deaths in men throughout the world. This study aimed to investigate genes associated with the pathogenesis and prognosis of PCa. Materials & methods: Data of PCa cases were obtained from public datasets and were analyzed using an integrated bioinformatics strategy. Results: A total of 969 differential expression genes were identified. Moreover, GSE16560 and The Cancer Genome Atlas (TCGA) data showed a prognostic prompt function of the nine-gene signature, as well as in PCa with Gleason 7. Finally, majority of the nine hub genes were associated with drug sensitivity, mutational landscape, immune infiltrates and clinical characteristics of PCa. Conclusion: The nine-gene signature was correlated with drug sensitivity, mutational landscape, immune infiltrates, clinical characteristics and survival from PCa.
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Perfilação da Expressão Gênica , Genômica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/diagnósticoRESUMO
Understanding the soil respiration characteristics in response to nitrogen and phosphorus addition in farming-withdrawn grasslands within semi-arid loess hilly-gully regions is of great importance for providing a theoretical basis for evaluating the effects of artificial regulation approaches on carbon cycling. We report on a field experiment that was undertaken from May to September 2018 in a farming-withdrawn grassland ecosystem in China, which is dominated by Stipa bungeana and Lespedeza davurica. Three different levels of nitrogen and phosphorus additions were used, including three main plots of N[0, 50, and 100 kg·(hm2·a)-1] and three subplots of P (P2O5)[0,40, and 80 kg·(hm2·a)-1]. The soil respiration rate, heterotrophic respiration rate, soil temperature, and soil moisture were measured monthly in each treatment. Results showed that N and P addition had no effect on soil temperature or moisture content (P>0.05). The soil respiration rate showed an obvious monthly variation and peaked in July. In the treatment without fertilizer addition, the monthly mean soil respiration rate, heterotrophic respiration rate, and autotrophic respiration rate were 0.69, 0.39, and 0.29 g·(m2·h)-1, respectively. P addition had no significant effect on the soil respiration rate and its components without N addition (P>0.05). Under conditions of N addition, P addition significantly increased the soil respiration rate and its component (P<0.05). The monthly mean soil respiration rate, heterotrophic respiration rate, and autotrophic respiration rate were 0.93, 0.50, and 0.47 g·(m2·h)-1, respectively. The Q10 (i.e., temperature sensitivity) values for soil respiration, heterotrophic respiration, and autotrophic respiration in unfertilized soil were 1.86, 2.36, and 2.24, respectively. The addition of N and P reduced the Q10 value of soil respiration and its components. Our findings suggest that the response of soil respiration and its two components to N and P addition in studied farming-withdrawn grassland in the semiarid loess hilly-gully region were closely related to their addition amounts.
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Pradaria , Nitrogênio/química , Fósforo/química , Solo/química , Agricultura , ChinaRESUMO
To analyze plant functional traits of dominant species to nitrogen and phosphorus addition, three species (Bothriochloa ischaemum, Stipa bungeana, and Lespedeza davurica) were selected in the loess hilly-gully region. A split-plot experiment which included three N treatments (0, 50, and 100 kg N·hm-2·a-1) and three P treatments (0, 40, and 80 kg P2O5·hm-2·a-1) was conducted. At the fast-growing stage, leaf length, leaf width, specific leaf area, leaf dry matter content, leaf N content, leaf P content, and leaf N:P were measured. Results showed that under 50 and 100 kg N·hm-2·a-1 treatments, leaf length and width of B. ischaemum increased significantly by 35.3% and 64.4%, respectively, while only the leaf length of S. bungeana and the leaf width of L. davurica increased significantly by 58.8% and 33.9%, respectively. Leaf dry matter content of the three species decreased significantly by 10.7%, 15.3% and 11.2%, respectively. Leaf N content and N:P of B. ischaemum and S. bungeana increased significantly by 23.0% and 99.2%, 45.8% and 96.9%, respectively, compared with unfertilized treatments. Under 40 and 80 kg P2O5·hm-2·a-1 treatments, leaf length, leaf width and specific leaf area of L. davurica increased significantly by 56.9%, 41.4% and 19.6%, respectively, while leaf dry matter content decreased significantly by 14.9%. Leaf P content of three species increased significantly by 96.7%, 110.9% and 238.4%, while the N:P decreased significantly by 45.8%, 42.8% and 53.7%, respectively, compared with those under unfertilized. Under 50 kg N·hm-2·a-1 treatment, compared with no P application, leaf length and leaf width of L. davurica and leaf P content of the three species significantly increased, and leaf N content of B. ischaemum and S. bungeana decreased significantly at 40 and 80 kg P2O5·hm-2·a-1 treatments. Under 100 kg N·hm-2·a-1 treatment, leaf length of B. ischaemum and S. bungeana, leaf width of L. davurica and leaf P content of three species significantly increased, while leaf N content of B. ischaemum decreased significantly after P application. In summary, functional traits of dominant species showed significant responses to short-term nitrogen and phosphorus addition, with the different responses were mainly related to species traits and fertilization levels. Such difference reflected plant adaptation to habitat changes. The divergent responses of different species to nitrogen and phosphorus addition played an important role in maintaining diversity and stability of grassland communities.
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Nitrogênio , Fósforo , Pradaria , Folhas de Planta , PoaceaeRESUMO
Amphoteric modification can simultaneously improve the adsorption of organic pollutants and heavy metals on clay minerals. Study of the adsorption and interaction of multiple heavy metals on amphoteric modified soils is therefore of practical significance. Here, bentonite-(CK) and 150BS-12-modified bentonites (150BS-12) were characterized both before and after metal ion adsorption using Fourier-transform infrared spectroscopy (FTIR). The equilibrium adsorption characteristics and differences of Cu2+ and Pb2+ in single and binary systems were studied by batch methods. The interaction mechanism of the metals on modified bentonites is also discussed. The results showed that the adsorption capacity of Cu2+ and Pb2+ in single and binary systems was ranked, in descending order, as 150BS-12 > 100BS-12 > 50BS-12 > CK, and that the adsorption isotherm could be described by the Langmuir and Freundlich equations. Although the modification of BS-12 was more beneficial for the adsorption of Cu2+, the adsorption capacity and selectivity coefficient of Pb2+ on BS-12-modified bentonites were larger than for Cu2+. Cu2+ and Pb2+ had a mutually antagonistic effect on each other; modification with BS-12 enhanced the effect of Cu2+ on Pb2+ and weakened the effect of Pb2+ on Cu2+, which was always stronger than the effect of Cu2+ on Pb2+. Increases in temperature and pH, and a reduction in ionic strength, can increase the adsorption of Cu2+ and Pb2+; however, the influence of these factors varied between the two metals, which also affected the interaction between the metals.
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We have developed a Ni-catalyzed enantioselective hydroarylation of styrenes with arylboronic acids using MeOH as the hydrogen source, providing an efficient method to access 1,1-diarylalkanes, which are essential structural units in many biologically active compounds. In addition, Ni-catalyzed enantioselective hydrovinylation of styrenes with vinylboronic acids is also realized with good yields and enantioselectivities. The synthetic utility was demonstrated by the efficient synthesis of ( R)-(-)-ibuprofen.
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BACKGROUND: Metastasis of prostate cancer (PCa) is largely affected by natural killer (NK) cells. This study aimed to clarify the mechanisms underlying tumor cells escaping from NK cells mediated by HIF-1α. METHODS: MiR-224 expression in lymphocytes and HIF-1α protein level in NK cells were determined by qRT-PCR and western blot, respectively. The amount of NKp46+ NK cells was detected with flow cytometry. The IFN-γ level was examined by enzyme linked immunosorbent assay (ELISA). NK cells were tested for cytolytic activity with a Non-Radioactive Cytotoxicity Assay, and treated with oxygenglucose deprivation (OGD) for hypoxia simulation. Interaction between miR-224 and NCR1 was evaluated with dual luciferase reporter assay. RESULTS: MiR-224 was down-regulated in lymphocytes isolated from prostate cancer tissues (nâ¯=â¯10). Overexpression of miR-224 protected prostate cancer from NK cells. HIF-1α increased miR-224 to inhibit the killing capability of NK cells on prostate cancer. MiR-224 controlled the expression of NCR1. Overexpression of miR-224 protected prostate cancer from NK cells through NCR1/NKp46 signaling. Suppression of HIF-1α enhanced the cytotoxicity of NK cells on prostate cancer via miR-224/NCR1 pathway. CONCLUSION: HIF-1α inhibits NCR1/NKp46 pathway through up-regulating miR-224, which affects the killing capability of NK cells on prostate cancer, thus inducing immune escape of tumor cells.