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1.
ACS Omega ; 9(25): 27492-27498, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947779

RESUMO

Diamond nanopillar arrays can enhance the fluorescence collection of diamond color centers, playing a crucial role in quantum communication and quantum sensing. In this paper, the preparation of diamond nanopillar arrays was realized by the processes of polystyrene (PS) sphere array film preparation, PS sphere etching shrinkage control, tilted magnetron sputtering of copper film, and oxygen plasma etching. Closely aligned PS sphere array films were prepared on the diamond surface by the gas-liquid interfacial method, and the effects of ethanol and dodecamethylacrylic acid solutions on the formation of the array films were discussed. Controllable reduction of PS sphere diameter is realized by the oxygen plasma etching process, and the changes of the PS sphere array film under the influence of etching power, bias power, and etching time are discussed. Copper antietching films were prepared at the top of arrayed PS spheres by the tilted magnetron sputtering method, and the antietching effect of copper films with different thicknesses was explored. Diamond nanopillar arrays were prepared by oxygen plasma etching, and the effects of etching under different process parameters were discussed. The prepared diamond nanopillars were in hexagonal close-rowed arrays with a spacing of 800 nm and an average diameter of 404 nm, and the spacing, diameter, and height could be parametrically regulated. Raman spectroscopy and photoluminescence spectroscopy detection revealed that the prepared diamond nanopillar array still maintains polycrystalline diamond properties, with only a small amount of the graphite phase appearing. Moreover, the prepared diamond nanopillar array can enhance the photoluminescence of diamond color centers by approximately 2 times. The fabrication method of diamond nanopillar array structures described in this article lays the foundation for quantum sensing technology based on diamond nanostructures.

2.
PLoS One ; 19(6): e0304478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870180

RESUMO

In the context of the evolving landscape of reduction in carbon emissions and integration of renewable energy, this study uses system dynamics (SD) modeling to explore the interconnected dynamics of carbon trading (CT), tradable green certificate (TGC) trading, and electricity markets. Using differential equations with time delays, the study provides a comprehensive analysis of structural relationships and feedback mechanisms within and between these markets. Key findings reveal the intricate interplay between carbon prices, green certificate prices, and electricity prices under various coupling mechanisms. For example, under the three-market coupling mechanism, carbon trading prices stabilize around 150 Yuan/ton, while green certificate prices reach a peak of 0.45 Yuan/KWH, impacting electricity prices, which fluctuate between 0.33 and 1.09 Yuan / KWH during the simulation period. These quantitative results shed light on nuanced fluctuations in market prices and the dynamics of anticipated purchases and sales volumes within each market. The insights gleaned from this study offer valuable implications for policy makers and market stakeholders in navigating the complexities of carbon emission reduction strategies, the integration of renewable energy and market equilibrium. By understanding the dynamics of multi-market coupling, stakeholders can better formulate policies and strategies to achieve sustainable energy transitions and mitigate impacts of climate change.


Assuntos
Carbono , Eletricidade , Energia Renovável/economia , Modelos Econômicos , Comércio/economia , Modelos Teóricos
3.
Molecules ; 28(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37959733

RESUMO

Sodium-ion batteries (SIBs) are promising alternatives to replace lithium-ion batteries as future energy storage batteries because of their abundant sodium resources, low cost, and high charging efficiency. In order to match the high energy capacity and density, designing an atomically doped carbonous material as the anode is presently one of the important strategies to commercialize SIBs. In this work, we report the preparation of high-performance dual-atom-doped carbon (C) materials using low-cost corn starch and thiourea (CH4N2S) as the precursors. The electronegativity and radii of the doped atoms and C are different, which can vary the embedding properties of sodium ions (Na+) into/on C. As sulfur (S) can effectively expand the layer spacing, it provides more channels for embedding and de-embedding Na+. The synergistic effect of N and S co-doping can remarkably boost the performance of SIBs. The capacity is preserved at 400 mAh g -1 after 200 cycles at 500 mA g-1; more notably, the initial Coulombic efficiency is 81%. Even at a high rate of high current of 10 A g-1, the cell capacity can still reach 170 mAh g-1. More importantly, after 3000 cycles at 1 A g-1, the capacity decay is less than 0.003% per cycle, which demonstrates its excellent electrochemical performance. These results indicate that high-performance carbon materials can be prepared using low-cost corn starch and thiourea.

4.
Front Psychol ; 13: 707172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496167

RESUMO

The salience of social risks and the incidence of various crises in China have induced widespread concerns among urban residents. Encountering frequent risks places higher demands on the cognition of urban residents. The concept of safety cognition capability is defined within the context of urban residents' daily life, and measurement instruments are developed and tested to lay the foundation for grasping the current safety cognition capability of urban residents and conducting further research. In this study, the five-dimensional structure of urban residents' safety cognition capability (URSCC) was proposed by using the grounded theory method to sort out the interview transcript of interviews with 30 urban residents, and a 38-item URSCC scale was designed and used for surveys conducted in China. The results show that the scale can be used as a valid tool to measure the URSCC, and it can help city managers to better understand the safety needs of residents, as well as monitor the effectiveness of policy implementation.

5.
Front Vet Sci ; 8: 675962, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124228

RESUMO

Probiotics serving as an alternative to the criticized antibiotics mainly focus on improving animal's growth and health. After realizing the dangers posed by diseases that have led to lots of economic losses, aquaculture scientists have sought the usage of probiotics. However, most probiotics are ineffective in eliciting aquatic animals' preferred effects, since they are from non-fish sources. Again, there are even a few marine aquatic probiotics. Given this, a study was conducted to investigate the probiotic potential of the bacteria species isolated from the digestive tract of hybrid grouper (Epinephelus fuscoguttatus♀ × Epinephelus lanceolatus♂). Based on the morphological, biochemical, 16S rRNA sequencing analysis and evolutionary relationships, the isolated species were identified as Bacillus tequilensis GPSAK2 (MW548630), Bacillus velezensis GPSAK4 (MW548635), and Bacillus subtilis GPSAK9 (MW548634), which were designated as GPSAK2, GPSAK4, and GPSAK9 strains, respectively. Their probiotic potentials including their ability to tolerate high bile salt concentration, low pH, high temperatures, adhesion ability (auto-aggregation and cell-surface hydrophobicity), antimicrobial activity and biosafety test, compatibility test, hemolytic activity, and antibiotic susceptibility test were evaluated. While GPSAK2 and GPSAK9 strains were γ-hemolytic, that of GPSAK4 was α-hemolytic. All the isolates were resistant to low pH (1) and higher bile salt concentration (0.5%), showed higher viability ability after higher temperature exposure (80, 90, and 100°C), as well as higher cell-surface percentage hydrophobicity and auto-aggregation. All isolates exhibited positive compatibility with each other, signifying their ability to be used as multispecies. The three strains were susceptible to ampicillin (except GPSAK9, which was resistant), penicillin, kanamycin, ceftriaxone, chloramphenicol, erythromycin, clindamycin, furazolidone (except GPSAK2 and GPSAK9, which were moderately susceptible and resistant, respectively), polymyxin B, vancomycin (except GPSAK9, which was resistant), sulfamethoxazole (except GPSAK9, which was moderately susceptible), amikacin, minocycline, ofloxacin, norfloxacin, doxycycline, neomycin, gentamicin, tetracycline, carbenicillin, midecamycin (except GPSAK9, which was moderately susceptible), ciprofloxacin, piperacillin, and cefoperazone. All isolates demonstrated good antimicrobial activity against four pathogens, viz. Streptococcus agalactiae, Streptococcus iniae, Vibrio harveyi, and Vibrio alginolyticus. The results collectively suggest that Bacillus strains GPSAK2, GPSAK4, and GPSAK9 could serve as potential probiotic candidates that can be used to improve the growth and health status of aquatic animals, especially grouper.

6.
Eur J Pharm Sci ; 163: 105868, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33951483

RESUMO

Ceftazidime is a third-generation cephalosporin with high activity against many pathogens. But the ambiguity and diversity of the dosing regimens in neonates and young infants impair access to effective treatment. Thus, we conducted a population pharmacokinetic study of ceftazidime in this vulnerable population and recommended a model-based dosage regimen to optimize sepsis therapy. Totally 146 neonates and young infants (gestational age (GA): 36-43.4 weeks, postnatal age (PNA): 1-81 days, current weight (CW): 900-4500 g) were enrolled based on inclusion and exclusion criteria. Ceftazidime bloods samples (203) were obtained using the opportunistic sampling strategy and determined by the high-performance liquid chromatography. The population pharmacokinetic-pharmacodynamic analysis was conducted by nonlinear mixed effects model (NONMEM). A one-compartment model with first-order elimination best described the pharmacokinetic data. Covariate analysis showed the significance of GA, PNA, and CW on developmental pharmacokinetics. Monte Carlo simulation was performed based on above covariates and minimum inhibitory concentration (MIC). In the newborns with PNA ≤ 3 days (MIC=8 mg/L), the dose regimen was 25 mg/kg twice daily (BID). For the newborns with PNA > 3 days (MIC=16 mg/L), the optimal dose was 30 mg/kg three times daily (TID) for those with GA ≤ 37 weeks and 40 mg/kg TID for those with GA > 37 weeks. Overall, on the basis of the developmental population pharmacokinetic-pharmacodynamic analysis covering the whole range of neonates and young infants, the evidence-based ceftazidime dosage regimens were proposed to optimize neonatal early-onset and late-onset sepsis therapy.


Assuntos
Sepse Neonatal , Sepse , Antibacterianos/uso terapêutico , Ceftazidima , Humanos , Lactente , Recém-Nascido , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Sepse Neonatal/tratamento farmacológico , Sepse/tratamento farmacológico
7.
PLoS One ; 14(5): e0216476, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31083686

RESUMO

Map-matching technology is a key and difficult technology in the development of vehicle navigation systems. Only by correctly identifying the road segment on which the vehicle is traveling can the navigation system make the right decision. At the same time, the complexity of the road network structure and a variety of error factors have introduced great challenges to map matching and have attracted the attention of many researchers as well. This paper analyzes various map-matching algorithms, determines that the key to the matching performance is the junction matching, performs an in-depth study on the junction-matching problem, and puts forward the junction decision domain model. The model mainly involves information regarding the width of the road segment, the angle between two road segments, the accuracy of GPS and the accuracy of the road network. In this paper, we use this model to improve the map-matching algorithm based on a hidden Markov model (HMM). The experimental results show that the improved matching algorithm can effectively reduce the error rate of junction matching and improve the matching performance of a navigation system.


Assuntos
Algoritmos , Tomada de Decisões Assistida por Computador , Sistemas de Informação Geográfica , Modelos Teóricos , Cadeias de Markov
8.
Food Funct ; 9(7): 3807-3814, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29932194

RESUMO

An efficient method combined with fingerprint and chemometric analyses was developed to evaluate the quality of the traditional Chinese medicine plant Penthorum chinense Pursh. Nine samples were collected from different regions during different harvest periods, and 17 components in the form of extracts were simultaneously examined to assess quality by using high-performance liquid chromatography. The hepatoprotective effects of components were investigated by assessing the inhibition of SMMC-7721 cell growth. The results indicated that the quality control method was accurate, stable, and reliable, and the hierarchical heat-map cluster and the principle component analyses confirmed that the classification of all nine samples was consistent. Quercetin and ellagitannins including pinocembrin-7-O-[3''-O-galloyl-4'',6''-hexahydroxydiphenoyl]-ß-glucose (PGHG), thonningianin A, thonningianin B, and other flavonoids were abundant in the extracts, and significantly contributed to the hepatoprotective effects.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Magnoliopsida/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Flavonoides/química , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/fisiopatologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-29941652

RESUMO

Azithromycin is extensively used in children with community-acquired pneumonia (CAP). Currently, the intravenous azithromycin is used off-label in children partly due to lacking of pharmacokinetic data. Our objective was to evaluate the population pharmacokinetics (PPK) and optimize dose strategy in order to improve treatment in this distinctive population. This was a prospective, multicenter, open-labeled pharmacokinetic study. Blood samples were collected from hospitalized pediatric patients and concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). PPK analysis was conducted using NONMEM software. The pharmacokinetic data from 95 pediatric patients (age range, 2.1 to 11.7 years) were available for analysis. The PPK was best fitted by a two-compartment model with linear elimination. Covariate analysis verified that body weight and alanine aminotransferase (ALT) had significant effects on azithromycin pharmacokinetics, yielding a 24% decrease of clearance in patients with ALT of >40. Monte Carlo simulation showed that for children with normal liver function, a loading-dose strategy (a loading dose of 15 mg/kg of body weight followed by maintenance doses of 10 mg/kg) would achieve the ratio of the area under free drug plasma concentration-time curve over 24 h (fAUC) to MIC90 (fAUC/MIC) target of 3 h in 53.2% of hypothetical patients, using a normative MIC susceptibility breakpoint of 2 mg/liter. For children with ALT of >40, the proposed dose needed to decrease by 15% to achieve comparable exposure. The corresponding risk of overdose for the recommended dosing regimen was less than 5.8%. In conclusion, the PPK of azithromycin was evaluated in children with CAP and an optimal dosing regimen was constructed based on developmental pharmacokinetic-pharmacodynamic modeling and simulation.


Assuntos
Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Azitromicina/farmacocinética , Azitromicina/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Pneumonia/tratamento farmacológico , Alanina Transaminase/metabolismo , Criança , Pré-Escolar , Cromatografia Líquida/métodos , Infecções Comunitárias Adquiridas/metabolismo , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Método de Monte Carlo , Pneumonia/metabolismo , Estudos Prospectivos , Espectrometria de Massas em Tandem/métodos
10.
RSC Adv ; 8(15): 8393-8401, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35541988

RESUMO

Developing electromagnetic wave absorbing materials prepared by a facile and economical way is a great challenge. Herein, we report a feasible route to synthesize a series of two-dimensional FeNi/rGO composites by a hydrothermal method followed by a carbonization process. The characterization confirms that nano-sized FeNi alloy nanoparticles are evenly supported onto graphene sheets without aggregation. The homogeneous dispersion of the nanoparticles may result from the introduction of glucose and the oxygen-containing groups on the surface of the graphene oxide. Measurements show that the microwave attenuation capability of the composites can be improved dramatically by adjusting the proportion of dielectric and magnetic components. Consequently, the two-dimensional magnetic material (FeNi/rGO-100) exhibits an excellent microwave absorption performance. In detail, the minimum reflection loss of -42.6 dB and effective bandwidth of 4.0 GHz can be reached with a thinner thickness of 1.5 mm. This study demonstrates that synergistic effects among the magnetic particles, reduced graphene oxide and amorphous carbon layers give rise to the highlighted microwave attenuation ability. Overall, the FeNi/rGO composite is a promising candidate to be used as a microwave absorber, and the feasible and economical method has shown potential application to construct multitudinous two-dimensional materials.

11.
Int J Antimicrob Agents ; 49(6): 757-762, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28456705

RESUMO

Mycobacterium tuberculosis Beijing genotype strains increasingly circulate in different world regions, either as historical endemic, e.g. in East Asia, or recently imported, e.g. in South America, and this family is regarded as the most successful lineage of the global tuberculosis (TB) epidemic. Here we analysed the transmission capacity of these strains in the context of their phylogenetic background and drug resistance mutations. The study collection included all multidrug resistant (MDR) strains of Beijing genotype isolated in Beijing Chest Hospital, the largest tertiary TB facility in North China, in 2011-2013 (n = 278). Strains were subjected to NTF/IS6110 and 24-loci MIRU-VNTR analysis. Drug resistance mutations were detected in rpoB, katG, inhA and oxyR-ahpC. A total of 58 and 220 strains were assigned to the ancient and modern Beijing sublineages, respectively. 24-MIRU-VNTR clustering was higher in modern versus ancient Beijing strains (35.9% vs. 12.1%; P <0.001). After taking into consideration the presence of rpoB and katG mutations, clustering decreased to 15.9% in modern and 0% in ancient strains. The most frequent combination of mutations (rpoB531-TTG and katG315-ACC) was more prevalent in clustered versus non-clustered isolates in the modern sublineage (23/35 vs. 47/185; P <0.0001). To conclude, a combination of the known low-fitness-cost rpoB531-TTG and katG315-ACC mutations likely facilitates the increased transmission ability of MDR strains of the modern but not ancient Beijing sublineage. Accordingly, positive epistasis of major low-cost drug resistance-conferring mutations is influenced by the phylogenetic background of M. tuberculosis strains.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Mutação , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adulto , Idoso , China/epidemiologia , Análise por Conglomerados , Transmissão de Doença Infecciosa , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto Jovem
12.
Kidney Blood Press Res ; 41(6): 911-918, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27889773

RESUMO

BACKGROUND/AIMS: The aminolycoside Gentamicin is a widely used antibiotic, applied in equine medicine. Despite its clinical use, concerns remain regarding the potential toxic side-effects, such as nephrotoxicity. Early detection of renal damage is critical in preclinical drug development. This study was aimed to determine whether kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) may be early indicators in the assessment of Gentamycin-induced nephrotoxicity. METHODS: In our study, a model of Gentamicin-induced nephrotoxicity in male Sprague Dawley rats treated for up to 7 days at 50 or 100mg/kg/day was used to monitor the expressions of novel biomarkers of renal toxicity during the progression of acute kidney injury (AKI). Additionally, biomarkers were assessed in human kidney proximal epithelial cells (HK-2) treated with Gentamicin for 2, 6, 12, 24, 36 or 48h in vitro. RESULTS: Repeated administration of Gentamicin to rats for 1, 3, or 7 days resulted in a dose- and time-dependent increase in the expression of KIM-1 and NGAL. The expressions of the two biomarkers changed prior to renal tubule damage and increases in serum creatinine (SCr) and blood urea nitrogen (BUN) levels, suggesting their usefulness for predicting Gentamicin-induced acute kidney injury (AKI) in vivo. CONCLUSIONS: In contrast, no significant increase in the expression of the biomarker genes and proteins were evident in HK-2 cells after treated by Gentamycin for up to 48h, suggesting that they may not be suitable endpoints for sensitive detection of nephrotoxic effects in vitro.


Assuntos
Injúria Renal Aguda/sangue , Moléculas de Adesão Celular/sangue , Lipocalinas/sangue , Proteínas Proto-Oncogênicas/sangue , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Proteínas de Fase Aguda , Animais , Biomarcadores/sangue , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Gentamicinas/toxicidade , Humanos , Lipocalina-2 , Masculino , Ratos , Ratos Sprague-Dawley
13.
Acta Pharmacol Sin ; 30(12): 1666-73, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19915582

RESUMO

AIM: To explore the potential mitochondrial toxicities and their severities of intravenously administered metacavir, a nucleoside analog, in rhesus monkeys. METHODS: Totally 21 rhesus monkeys were randomly divided into 4 groups: metacavir 120 mg/kg group, metacavir 40 mg/kg group, zidovudine(AZT) 50 mg/kg group, and blank control group. Animals were killed after the completion of dosing or further observed in a 4-week recovery phase. Changes of structure of mitochondria in liver, kidney, skeletal muscles, and cardiac muscles were observed under transmission electron microscope(TEM). Changes of the activities of mitochondrial respiratory chain complexes and mitochondrial DNA were also determined. RESULTS: In metacavir 120 mg/kg group, some mitochondrial injuries were found in skeletal muscle, cardiac muscle, and liver, including that some cristae was broken and became sparse in density in the skeletal muscle, the morphology and size of mitochondria remained unchanged. Metacavir decreased the activities of respiratory chain complexes I and II and the mtDNA contents in three tissues in a dose-dependent manner; however, the extent of such decrease was lower than that in AZT 50 mg/kg group. The mitochondrial injuries in metacavir 40 mg/kg group were mild in each tissue and no obvious change in mitochondrial function was noted. On week 4 in the recovery phase, results showed that all these injuries were reversible after drug withdrawal. CONCLUSION: These results suggest that metacavir has not a high risk for potential mitochondrial-related effects in rhesus monkeys.


Assuntos
DNA Mitocondrial/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Mitocôndrias/efeitos dos fármacos , Nucleosídeos de Purina/agonistas , Animais , Feminino , Coração/efeitos dos fármacos , Injeções Intravenosas , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/ultraestrutura , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/ultraestrutura , Macaca mulatta , Masculino , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Nucleosídeos de Purina/administração & dosagem , Zidovudina/farmacologia
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