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1.
Opt Express ; 32(11): 20339-20349, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859147

RESUMO

This paper studies the dynamic response characteristics of the scanning angle in a liquid crystal cladding waveguide beam scanner. Based on liquid crystal dynamic theory, finite element analysis and vectorial refraction law, a dynamic response calculation model of scanning angle is constructed. The simulation results show that the dynamic responses of the scanning angle during the electric field-on and field-off processes are asymmetric, and exhibit "S"-shape and "L"-shape changing trends, respectively. In addition, by comparing with the bulk phase modulation response process of traditional liquid crystal devices, the intrinsic physical reason for the rapid light regulation of the liquid crystal cladding waveguide beam scanner is clarified to be that the liquid crystal close to the core layer has a faster rotation speed during the electric field-off process. Moreover, the liquid crystal cladding waveguide beam scanner is experimentally tested, and the experiment results are in good agreement with theoretical simulations.

2.
Environ Sci Technol ; 56(8): 5090-5101, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35344362

RESUMO

Silver nanoparticles (AgNPs) are effective antimicrobial substances that show promise in combatting multidrug resistance. The potential application and release of AgNPs into the environment may neutralize the selective advantage of antibiotic resistance. Systemic knowledge regarding the effect of NPs on the evolution of antibiotic resistance is lacking. Our results showed that bacteria slowly developed adaptive tolerance to ciprofloxacin (CIP) under cyclic CIP and silver ion (Ag+) cotreatment, and no resistance/tolerance was discernible when CIP and AgNP exposure was alternated. In contrast, rapid CIP resistance was induced under continuous selection by treatment with only CIP. To combat the effects of CIP and Ag+, bacteria developed convergent evolutionary strategies with similar adaptive mechanisms, including anaerobic respiration transitioning (to reduce oxidative stress) and stringent response (to survive harsh environments). Alternating AgNP exposure impeded evolutionary resistance by accelerating B12-dependent folate and methionine cycles, which reestablished DNA synthesis and partially offset high oxidative stress levels, in contrast with the effect of CIP-directed evolutionary pressure. Nevertheless, CIP/AgNP treatment was ineffective in attenuating virulence, and CIP/Ag+ exposure even induced the virulence-critical type III secretion system. Our results increase the basic understanding of the impacts of NPs on evolutionary biology and suggest prospective nanotechnology applications for arresting evolutionary antibiotic resistance.


Assuntos
Nanopartículas Metálicas , Prata , Ciprofloxacina/farmacologia , Resistência Microbiana a Medicamentos , Íons , Estudos Prospectivos , Prata/farmacologia
3.
J Sep Sci ; 44(19): 3600-3607, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34329529

RESUMO

This work presents the investigation of using tocopheryl polyethylene glycol succinate as the stationary phase for gas chromatography separations of isomers with different varieties and gas chromatography-mass spectrometry analysis of a wide range of components in lavender essential oil. Its capillary column exhibited moderate polarity and column efficiency of 4000 plates/m determined by n-dodecane at 120°C. As demonstrated, it showed outstanding separation performance toward challenging isomers such as xylenes, alkanes, phenols, and anilines and a wide range of components in essential oils with distinct advantages over the commercial polyethylene glycol and polysiloxane columns. Moreover, its capillary columns displayed excellent repeatability and reproducibility with the RSD values of the retention times in the range of 0.02-0.07% for run-to-run, 0.14-0.22% for day-to-day, and 2.5-4.3% for column-to-column. Its application to gas chromatography-mass spectrometry analysis of the lavender essential oil proved its good potential for practical gas chromatography analyses. To our knowledge, this work presents the first example of employing tocopheryl polyethylene glycol succinate for chromatographic analyses and demonstrates its promising future in this field.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/análise , Óleos de Plantas/análise , Vitamina E/química , Lavandula/química , Óleos Voláteis/química , Óleos de Plantas/química , Reprodutibilidade dos Testes
4.
Nano Lett ; 20(2): 1455-1460, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31916445

RESUMO

The use of nanomaterials to regulate cell surface receptors is considered a novel strategy to manipulate cell behaviors. However, recognition is important to drive nanoparticle-cell complex formation. Here, we report a novel approach that uses graphene oxide (GO) as a chemoattractant to lure bacteria to nanosurface, facilitating complex formation. The amount of Escherichia coli (E. coli) cells attracted into capillaries containing 20 mg/L GO was more than 8.6-fold higher than that attracted into capillaries containing 20 mg/L glucose. The inherent mechanism involved interference with transmembrane chemoreceptors and activation of the chemotactic system via GO attachment and a subsequent increase in cell aggregation and migration via self-secreted quorum sensing molecules. The key feature of this strategy is the potential to improve the efficiency of the nanoparticle-cell recognition pattern and to expedite the development of surface-contact-related nanotechnology.


Assuntos
Fatores Quimiotáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Grafite/química , Nanoestruturas/química , Antibacterianos/química , Antibacterianos/farmacologia , Fatores Quimiotáticos/química , Glucose/farmacologia , Nanopartículas/química , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/química
5.
Pak J Pharm Sci ; 34(2): 621-627, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275838

RESUMO

Rhizoma Drynariae, the dried rhizome of Drynaria fortunei (Kunze), is rich in flavonoids and has varieties of pharmacological activities. To optimize the extract conditions for bioactive flavonoids, a response surface methodology (RSM) was utilized to assess the effects of three independent variables (liquid-to-solid ratio (mL/g), extract temperature (°C) and ethanol concentration (%) on the total flavonoids content (TFC). To test the chelation with metal ion, the UV-visible spectrophotometer was used to detect metal ion chelation of extracted flavonoids. Regression analysis displayed a good fit of the experimental data. The optimal condition was liquid-to-solid ratio with 50:1, extract temperature with 80 °C and ethanol concentration with 40.22%. The total flavonoids had a better chelation with metal ions Cu2+, Fe2+, Fe3+ than Zn2+. These results suggested that the model employed is suitable and the application of RSM in optimizing the extract conditions is successful. The experimental values were in fine agreement (the yield 24.05±0.69mg/g) with predicted values. The total flavonoids from the extract presented good chelation against four metal ions (Cu2+, Zn2+, Fe2+ and Fe3+), which provided a good evidence for Alzheimer's disease treatments.


Assuntos
Técnicas de Química Analítica/métodos , Flavonoides/química , Extratos Vegetais/química , Polypodiaceae , Rizoma , Quelantes/farmacologia , Química Farmacêutica , Cobre , Etanol , Compostos Férricos , Compostos Ferrosos , Flavonoides/farmacologia , Raízes de Plantas , Solventes , Temperatura , Zinco
6.
Chemistry ; 24(23): 6277-6281, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29498105

RESUMO

The dearomatizative dienamine-type ortho-quinodimethane species are smoothly generated between 2-alkyl-3-furfurals and chiral secondary amine catalysts, which undergo asymmetric benzylic allylic alkylation reactions with 2-nitroallylic acetates efficiently. A spectrum of densely functionalized 3-furfural derivatives are delivered in moderate to high yields with good to excellent diastereo- and enantioselectivity (up to 98 % yield, >19:1 d.r., >99 % ee). The latent transformations allow the facile production of some enantioenriched architectures, such as 1,1,2,2-tetraarylethanes and triarylmethanes, which are not easily available from other protocols.

7.
Environ Sci Technol ; 52(21): 12783-12791, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30277752

RESUMO

Microbial reduction of graphene oxide (GO) under aerobic conditions is poorly understood despite its critical role in changing GO toxicity and environmental fate. Here we show that 20 mg/L GO interacts with the membrane-bound cytochrome c of E. coli in saline, shuttling electrons from the respiratory chain to extracellular molecular oxygen. This results in the formation of superoxide anions (O2•-), which in turn reduce GO in 30 min. The critical role of superoxide was demonstrated by impeding GO reduction upon addition of superoxide dismutase, or by carrying out experiments under strictly anaerobic conditions that preclude O2•- formation. Coating GO with bovine serum albumin also stopped GO reduction, which indicates the need for direct contact between GO and the cell membrane. Cell death was observed as a consequence of GO bioreduction. Apparently, electron shuttling by GO (via membrane contact) interrupts the respiratory chain and induces oxidative stress, as indicated by a 20% decrease in electron transport activity and an increase in intracellular reactive oxygen species. This novel antimicrobial mechanism could be relevant to assess GO stability and biocompatibility, and informs potential applications for microbial control.


Assuntos
Grafite , Escherichia coli , Óxidos , Espécies Reativas de Oxigênio , Superóxidos
8.
Zhong Yao Cai ; 38(4): 831-4, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26672354

RESUMO

OBJECTIVE: To compare the purification effect of saponins from Ziziphi Spinosae Semen with different types of macroporous adsorption resin, and to optimize its purification technology. METHODS: The type of macroporous resins was optimized by static adsorption method. The optimum technological conditions of saponins from Ziziphi Spinosae Semen was screened by single factor test and Box-Behnken Design-Response Surface Methodology. RESULTS: AB-8 macroporous resin had better purification effect of total saponins than other resins, optimum technological parameters were as follows: column height-diameter ratio was 5: 1, the concentration of sample solution was 2. 52 mg/mL, resin adsorption quantity was 8. 915 mg/g, eluted by 3 BV water, flow rate of adsorption and elution was 2 BV/h, elution solvent was 75% ethanol, elution solvent volume was 5 BV. CONCLUSION: AB-8 macroporous resin has a good purification effect on jujuboside A. The optimized technology is stable and feasible.


Assuntos
Resinas Vegetais/química , Saponinas/isolamento & purificação , Sementes/química , Ziziphus/química , Adsorção , Medicamentos de Ervas Chinesas/química , Etanol , Solventes , Tecnologia Farmacêutica , Água
9.
Sci Total Environ ; 913: 169682, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38163607

RESUMO

Nanoparticles (NPs) hold great promise for agricultural applications, yet their potential impact on exogenous gene transfer within plant remains poorly understood. In this study, we utilized the non-conjugative plasmid pCAMBIA1300, harboring the bialaphos resistance (bar) gene expressed in plant and the kanamycin resistance (kanR) gene as selectable marker in bacteria. Our results revealed a significant increase in the transfer of plasmid (via carrier Escherichia coli DH5α), both intra- and inter-species within the endophyte, when Arabidopsis thaliana was exposed to environmentally relevant level of zinc oxide (ZnO) NPs at a concentration of 0.7 µg/mL throughout its lifespan. Intriguingly, the plasmid exhibited selective transfer to growth-promoting endophytes, such as Enterobacter, Serratia, and Achromobacter, with the presence of ZnO NPs expanding the pool of potential recipients. This result is due to the facilitation of an endophytic and mutualistic lifestyle of invasive E. coli DH5α and the enrichment of beneficial bacteria aided by ZnO NPs. The plant's descendant generations did not express the bar gene, and the endophytes carrying the exogenous plasmid did not transmit it to sub sequent generation. This research provides crucial insights for assessing the potential risks associated with gene contamination and ensuring the safe and sustainable use of NPs in agriculture.


Assuntos
Arabidopsis , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Endófitos , Arabidopsis/genética , Escherichia coli/genética , Bactérias/genética , Plasmídeos
10.
Pract Lab Med ; 40: e00413, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38974938

RESUMO

Background: D-dimer at a low level is important evidence for excluding the onset and progression of thrombosis. It is readily detectable and yields rapid results, although significant variability exists among different detection systems. Our study aims to enhance the consistency across various detection systems. Methods: Twelve detection systems were included in our study. We sought to address this inconsistency by using various calibrators (two supplied by manufacturers and two comprising pooled human plasma diluted with different diluents) to standardize D-dimer measurements. We categorized the data into three groups according to D-dimer concentration levels: low (≤0.5 mg/L), medium (>0.5 mg/L - <3 mg/L), and high (≥3 mg/L). We then analyzed the data focusing on range, consistency, comparability, negative coincidence rate, and false negative rate. Results: Calibrating with pooled human plasma led to narrower result ranges in the low and medium groups (P < 0.05). In the low group, consistency improved from weak to strong (ICC 0.4-0.7, P﹤0.05), while it remained excellent in the other groups and overall (ICCï¹¥0.75, P﹤0.05). The percentage of pairwise comparability increased in both the low and high groups. Additionally, there was an increase in the negative coincidence rate. Conclusion: These findings demonstrate that uniform calibration of D-dimer can significantly enhance the consistency of results across different detection systems.

11.
J Mol Neurosci ; 74(2): 32, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536538

RESUMO

Down syndrome (DS) is the most example of aneuploidy, resulting from an additional copy of all or part of chromosome 21. Competing endogenous RNAs (ceRNAs) play important roles in neuronal development and neurological defects. This study aimed to identify hub genes and synergistic crosstalk among ceRNAs in the DS fetal hippocampus as potential targets for the treatment of DS-related neurodegenerative diseases. We profiled differentially expressed long non-coding RNAs (DElncRNAs), differentially expressed circular RNAs (DEcircRNAs), differentially expressed microRNAs (DEmiRNAs), and differentially expressed messenger RNAs (DEmRNAs) in hippocampal samples from patients with or without DS. Functional enrichment analysis and gene set enrichment analysis were performed, and chromosome 21-related ceRNA and protein-protein interaction networks were constructed. Additionally, the correlations between lncRNA-mRNA and miRNA-mRNA expression in the samples and HEK293T cells were validated. Our finding of changes in the expression of some key genes and ncRNAs on chromosome 21 in DS might not fully conform to the gene dosage hypothesis. Moreover, we found that four lncRNAs (MIR99AHG, PLCB4, SNHG14, GIGYF2) and one circRNA (hsa_circ_0061697) may competitively bind with three miRNAs (hsa-miR-548b-5p, miR-730-5p, and hsa-miR-548i) and subsequently regulate five mRNAs (beta-1,3-galactosyltransferase 5 [B3GALT5], helicase lymphoid-specific [HELLS], thrombospondin-2 [THBS2], glycinamide ribonucleotide transformylase [GART], clathrin heavy chain like 1 [CLTCL1]). These RNAs, whether located on chromosome 21 or not, interact with each other and might activate the PI3K/Akt/mTOR and Wnt signaling pathways, which are involved in autophagosome formation and tau hyperphosphorylation, possibly leading to adverse consequences of trisomy 21. These findings provide researchers with a better understanding of the fundamental molecular mechanisms underlying DS-related progressive defects in neuronal development.


Assuntos
Síndrome de Down , MicroRNAs , RNA Longo não Codificante , Humanos , Síndrome de Down/genética , RNA Endógeno Competitivo , Células HEK293 , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , RNA Mensageiro/genética , RNA Circular/genética , Hipocampo , Redes Reguladoras de Genes
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(5): 518-21, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24078562

RESUMO

OBJECTIVE: To detect genetic mutations underlying non-syndromic hearing impairment (NSHI) and establish a method for prenatal diagnosis. METHODS: Sixty six NSHI patients were included in this study. DNA was extracted from peripheral blood. Genetic mutations were detected by gene chip analysis and direct sequencing of GJB2 gene. For 7 pregnant women at high risk, prenatal genetic diagnosis was provided. RESULTS: Fourteen cases (21.21%) were found to have GJB2 mutations by both methods (homozygous 235delC mutation in 3 cases, homozygous 176del16 mutation in 2 cases, 235delC and 299delAT compound heterozygous mutation in 2 cases, 299delAT and 176del16 compound heterozygous mutation in 1 case, c.339T > G and 313del12bp compound heterozygous mutation 1 case, and 235delC heterozygous mutation in 5 cases). 13 (19.70%) had SLC26A4 mutations (IVS7-2 A >G homozygous mutation in 2 cases, IVS7-2 A > G homozygous mutation in 2 cases, IVS7-2 A > G and 2168A > G compound heterozygous mutation in 3 cases, 2168A>G heterozygous mutation in 3 cases, and IVS7-2 heterozygous mutation in 3 cases); and 3 had mtDNA12S rRNA mutation (1555A > G mutation in 2 cases, 1494C > T mutation in 1 case). Prenatal diagnosis suggested that 3 fetuses have carried a heterozygous mutation. Two fetuses were detected as normal and confirmed to have normal hearing after birth. Two fetuses were found to have carried compound mutations of GJB2. CONCLUSION: Gene chip combined with GJB2 gene analysis is an accurate and effective method for the diagnosis of NSHI. The results can facilitate accurate prenatal diagnosis.


Assuntos
Perda Auditiva/genética , Adolescente , Adulto , Sequência de Bases , Criança , Pré-Escolar , Conexina 26 , Conexinas/genética , Feminino , Testes Genéticos , Perda Auditiva/diagnóstico , Humanos , Lactente , Masculino , Proteínas de Membrana Transportadoras/genética , Dados de Sequência Molecular , Mutação , Diagnóstico Pré-Natal , Transportadores de Sulfato , Adulto Jovem
13.
Environ Sci Pollut Res Int ; 30(17): 49075-49096, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36763267

RESUMO

Carbon trading price (CTP) prediction accuracy is critical for both market participants and policymakers. As things stand, most previous studies have only focused on one or a few carbon trading markets, implying that the models' universality is insufficient to be validated. By employing a case study of all carbon trading markets in China, this study proposes a hybrid point and interval CTP forecasting model. First, the Pearson correlation method is used to identify the key influencing factors of CTP. The original CTP data is then decomposed into multiple series using complete ensemble empirical mode decomposition with adaptive noise. Following that, the sample entropy method is used to reconstruct the series to reduce computational time and avoid overdecomposition. Following that, a long short-term memory method optimized by the Adam algorithm is established to achieve the point forecasting of CTP. Finally, the kernel density estimation method is used to predict CTP intervals. On the one hand, the results demonstrate the proposed model's validity and superiority. The interval prediction model, on the other hand, reflects the uncertainty of market participants' behavior, which is more practical in the operation of carbon trading markets.


Assuntos
Algoritmos , Comércio , Humanos , Comércio/métodos , China , Previsões , Carbono/análise
14.
Environ Sci Pollut Res Int ; 30(33): 79916-79936, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37291342

RESUMO

Multi-energy virtual power plant (MEVPP) has attracted more and more attention due to its advantages in renewable energy consumption and carbon emission reduction. However, the characteristics of multi-energy coupling and the access of renewable energy may lead to some challenges in the operation of MEVPP. In this paper, a data-driven distributionally robust chance constraints optimization model (DD-DRCCO) is proposed for the dispatching of MEVPP. Firstly, the uncertainties of wind power and photovoltaic output forecasting errors are modeled as an ambiguity set based on the Wasserstein metric. Secondly, combined with the chance constraint, the expected probability of the inequality constraint with uncertain variables is limited to the lowest allowable confidence level to improve the reliability of the model. Thirdly, the forecast errors of wind power and photovoltaic are considered in the constraint conditions, so that the system can effectively resist the interference of uncertain output. Besides, based on the strong duality theory, the DD-DRCCO model is equivalent to a MILP problem which is easy to solve. Finally, simulations implemented on a typical MEVPP are delivered to show that our proposed model: 1) The model is data-driven, and the conservativeness is kept at a low level, and the solution time is about 7s~8s; 2) The MEVPP system can achieve a balance between economy and low-carbon, making the total operation cost reduced by 0.89% compared with no increase of electric boiler; 3) The CO2 emission during the operation of the MEVPP system was significantly reduced by about 87.33 kg.


Assuntos
Carbono , Energia Renovável , Reprodutibilidade dos Testes , Centrais Elétricas , Incerteza
15.
Front Genet ; 14: 1216592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693308

RESUMO

Spondyloepiphyseal dysplasia tarda (SEDT) is a condition involving late-onset, X-linked recessive skeletal dysplasia caused by mutations in the TRAPPC2 gene. In this paper, we identified a novel nonsense variant in a SEDT pedigree and analyzed the function of the variant in an attempt to explain the new pathogenesis of the TRAPPC2 protein in SEDT. Briefly, DNA and RNA samples from the peripheral blood of SEDT individuals were prepared. The causative variant in the Chinese SEDT family was identified by clinic whole-exome sequencing analysis. Then, we observed the mRNA expression of TRAPPC2 in patients and the mutant TRAPPC2 level in vitro and analyzed the protein stability and subcellular distribution by cell fluorescence and Western blotting. We also investigated the effect of TRAPPC2 knockdown on the expression and secretion of COL2A1 in SW1353 cells or primary human chondrocytes. Herein, we found a nonsense variant, c.91A>T, of the TRAPPC2 gene in the pedigree. TRAPPC2 mRNA expression levels were significantly decreased in the available peripheral blood cell samples of two affected patients. An in vitro study showed that the mutant plasmid exhibited significantly lower mRNA and protein of TRAPPC2, and the mutant protein changed its membrane distribution. TRAPPC2 knockdown resulted in decreased COL2A1 expression and collagen II secretions. Our data indicate that the novel nonsense variant, c.91A>T, of the TRAPPC2 gene is the cause of SEDT in this pedigree. The variant results in a lowered expression of TRAPPC2 and then affects the COL2A1 expression and collagen II secretions, which may explain the mechanism of loss of function of the variant.

16.
Clin Appl Thromb Hemost ; 29: 10760296231153400, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36749023

RESUMO

Venous thromboembolism is a common complication following trauma. We investigated the dynamics of plasma microparticles (MPs) levels and explored their potential as biomarkers of deep vein thromboembolism (DVT) after trauma. A total of 775 patients with traumatic fractures were recruited in this nested study. About 106 trauma patients (53 DVT subjects and 53 age-, sex-, and fracture site-matched non-DVT subjects) and 53 healthy volunteers met the enrollment criteria. MPs were characterized by transmission electron microscope, nanoparticle tracking analysis, and western blotting. Circulating levels of MPs were measured using a flow cytometer. Meanwhile, routine laboratory parameters were examined in all patients. Compared to non-DVT patients, DVT patients had higher circulating phosphatidylserine (PS) + MPs, hepatocyte-derived MPs (HMPs), PS + HMPs, and platelet-derived MPs (PMPs). Notably, PS + HMPs had the best predictive value for DVT diagnosis in trauma patients (area under the curve [AUC] 0.8939, 95% CI 0.8326 to 0.9552), which was superior to d-dimer (AUC 0.5881). The Hepatic Procoagulant Index combined plasma levels of PS + HMPs and albumin, increasing the AUC to 0.8978 (95% CI 0.8396 to 0.9561). This is the first study that addressed circulating PS + HMPs are promising biomarkers with high performance in diagnosing DVT. The Hepatic Procoagulant Index is a potential predictor of DVT in trauma patients.


Assuntos
Micropartículas Derivadas de Células , Trombose Venosa , Humanos , Biomarcadores , Testes de Coagulação Sanguínea , Hepatócitos
17.
Sci Rep ; 12(1): 22376, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572695

RESUMO

By analysing the mechanical and geometrical relations between the main cable, tower, and splay saddles, and considering the coupling effect of the tower and splay saddles, an improved algorithm is proposed to determine the cable saddles pre-offsets of suspension bridges. The equilibrium relationship of the cable saddles, the compatible deformation condition, and the basic equation of the main cable shape are considered to establish several coupled non-linear equations up to 19, and the tower and splay saddle pre-offsets are obtained by solving the above equations with the Newton-Raphson method. This paper presents the initial value selection principle and the constraint conditions for solving the cable saddle pre-offsets of the plane cable suspension bridge and the calculation process ensures convergence. The calculation example demonstrates that the improved algorithm without an exact initial value can achieve excellent convergence.

18.
Microorganisms ; 10(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144409

RESUMO

Japanese larch (Larix kaempferi), a non-native tree species, has been widely planted in the Qinling Mountains since the last century, but it does not meet the habitat needs of giant pandas (Ailuropoda melanoleuca), mainly because of food, further causing habitat degradation and fragmentation. However, how soil microorganisms, considered as predictors of the soil environment, respond to Japanese larch remains poorly explored, especially compared with native forests. Here, we collected 40 soil samples from plantation, bamboo, and natural (excluding bamboo) forests in the Changqing Nature Reserve and Foping Nature Reserve in Qinling to compare soil bacterial community composition and diversity using high-throughput sequencing of bacterial 16S rRNA genes. The soil chemical properties and bacterial communities differed noticeably under forest-type classification patterns. The soil of the Japanese larch planted forests underwent substantial degradation, with higher acidity, lower alpha diversity, and more significant enrichment in the oligotrophic bacteria Acidobacteria and Verrucomicrobia, in contrast to the other two primary forests with elevated soil nutrient levels. The application of PICRUSt2 indicated the down-regulation of amino acid-related metabolism in planted forests. Moreover, pH was the primary factor determining the whole bacterial community structures. To avoid the uncertainty of a single sampling region, we chose different sampling sites that could be considered as geographical factors, possibly due to environmental heterogeneity or dispersal limitations, which also explained the specific community patterns of microorganisms. Overall, this paper may help provide a scientific basis for future revegetation in giant panda habitats, highlighting the urgent need for ecological restoration and sustainable forestry management.

19.
Environ Sci Pollut Res Int ; 29(48): 73577-73598, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35619011

RESUMO

As the proportion of renewable energy gradually increases, it brings challenges to the stable operation of the combined heat and power (CHP) system. As an important flexible resource, energy storage (ES) has attracted more and more attention. However, the profit of energy storage can't make up for the investment and operation cost, and there is a lack of measurement system for multiple values, which seriously hinders the development of energy storage industry. Based on this, this paper makes a quantitative analysis on the system value of multiple energy storage in CHP. Firstly, the uncertain output of renewable energy is characterized by Kullback-Leibler (KL) divergence, and a two-level dispatching model is constructed based on the distributionally robust optimization method, so as to study the optimal operation strategy of the ES-CHP system. Secondly, based on the system value theory, this paper analyzes the system value of multiple energy storage, including internal value and external value, and constructs the value quantitative model, respectively. Finally, in a typical ES-CHP system, the system value of multiple energy storage is quantified. The effectiveness of the two-level model constructed in this paper can be seen from the simulation results, and the influence of different electricity prices on the system value of multiple energy storage is further analyzed.

20.
Clin Chim Acta ; 536: 169-179, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36191610

RESUMO

OBJECTIVE: Venous thromboembolism (VTE) is a common and severe complication of joint arthroplasty. Microparticles (MPs) containing phosphatidylserine (PS) and tissue factor (TF) can trigger coagulation in VTE. This study aims to measure and compare MP levels in joint arthroplasty patients with and without VTE. METHODS: This prospective cohort study enrolled 181 patients who underwent joint arthroplasty. Ultrasound examination was used to diagnose VTE on preoperative day 0 and postoperative day 6. MPs were analysed using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and flow cytometry. The levels of platelet-derived microparticles (PMPs), endothelial cell-derived microparticles (EMPs), granulocyte-derived microparticles (GMPs), red cell-derived microparticles (RMPs), monocyte-derived microparticles (MMPs), Annexin V+ MPs (AV+ MPs), and tissue factor+ MPs (TF+ MPs) derived from five kinds of MPs were measured on day 0 (before surgery), 1, 2, 3, 4, 5, and 6 after surgery. RESULTS: The levels of AV-TF+ EMPs and AV-TF+ MMPs were significantly increased in patients with VTE on postoperative day 5 compared to those without VTE (P = 0.031 and P = 0.031, respectively). CONCLUSION: AV-TF+ MPs may indicate the development of VTE and serve as predictive markers in joint arthroplasty patients.


Assuntos
Micropartículas Derivadas de Células , Tromboembolia Venosa , Trombose Venosa , Anexina A5 , Artroplastia/efeitos adversos , Biomarcadores , Humanos , Fosfatidilserinas , Estudos Prospectivos , Tromboplastina/metabolismo , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia , Trombose Venosa/diagnóstico , Trombose Venosa/etiologia
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