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1.
Opt Lett ; 49(4): 1061-1064, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359253

RESUMO

We demonstrated an AlGaN-based multiple-quantum-well (MQW) deep ultraviolet (DUV) laser at 278 nm using a nanoporous (NP) n-AlGaN as the bottom cladding layer grown on the sapphire substrate. The laser has a very-low-threshold optically pumped power density of 79 kW/cm2 at room temperature and a transverse electric (TE)-polarization-dominant emission. The high optical confinement factor of 9.12% benefiting from the low refractive index of the nanoporous n-AlGaN is the key to enable a low-threshold lasing. The I-V electrical measurement demonstrates that an ohmic contact can be still achieved in the NP n-AlGaN with a larger but acceptable resistance, which indicates it is compatible with electrically driven laser devices. Our work provides insights into the design and fabrication of low-threshold lasers emitting in the DUV regime.

2.
Biomed Chromatogr ; 38(8): e5943, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38890009

RESUMO

In this study, a targeted nanocarrier was developed by functionalizing graphene oxide with polyethyleneimine and folic acid, intended for loading oridonin. The nanocarrier was successfully synthesized and characterized using an ultraviolet spectrum, Fourier transform infrared spectroscopy and scanning electron microscopy. The nanocarrier demonstrated a remarkable oridonin loading capacity, reaching 424.8 µg/mg, as determined by ultra-high performance liquid chromatography. In vitro drug release experiments exhibited a pH-dependent release profile, with a higher cumulative release in an acidic environment. The release mechanism followed the Ritger-Peppas equation model. Cytotoxicity assays indicated minimal toxicity of the nanocarrier. Enhanced cellular uptake by MCF7 cells was observed for carriers functionalized with folate and polyethyleneimine. These findings highlight the potential of functionalized graphene oxide as a promising carrier for oridonin delivery in biomedical applications.


Assuntos
Neoplasias da Mama , Diterpenos do Tipo Caurano , Portadores de Fármacos , Grafite , Grafite/química , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Humanos , Células MCF-7 , Portadores de Fármacos/química , Neoplasias da Mama/tratamento farmacológico , Feminino , Antineoplásicos/farmacologia , Antineoplásicos/química , Liberação Controlada de Fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Fólico/química , Nanopartículas/química , Cromatografia Líquida de Alta Pressão/métodos
3.
BMC Med Educ ; 24(1): 738, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982322

RESUMO

BACKGROUND: The purpose of this study was to evaluate the effectiveness and efficiency of implementing a data-driven blended online-offline (DDBOO) teaching approach in the medicinal chemistry course. METHODS: A total of 118 third-year students majoring in pharmacy were enrolled from September 2021 to January 2022. The participants were randomly assigned to either the DDBOO teaching group or the traditional lecture-based learning (LBL) group for medicinal chemistry. Pre- and post-class quizzes were administered, along with an anonymous questionnaire distributed to both groups to assess students' perceptions and experiences. RESULTS: There was no significant difference in the pre-class quiz scores between the DDBOO and LBL groups (T=-0.637, P = 0.822). However, after class, the mean quiz score of the DDBOO group was significantly higher than that of the LBL group (T = 3.742, P < 0.001). Furthermore, the scores for learning interest, learning motivation, self-learning skill, mastery of basic knowledge, teamwork skills, problem-solving ability, innovation ability, and satisfaction, as measured by the questionnaire, were significantly higher in the DDBOO group than in the traditional group (all P < 0.05). CONCLUSION: The DDBOO teaching method effectively enhances students' academic performance and satisfaction. Further research and promotion of this approach are warranted.


Assuntos
Química Farmacêutica , Educação em Farmácia , Avaliação Educacional , Estudantes de Farmácia , Feminino , Humanos , Masculino , Adulto Jovem , Química Farmacêutica/educação , Instrução por Computador/métodos , Currículo , Educação a Distância , Educação em Farmácia/métodos , Inquéritos e Questionários
4.
BMC Neurol ; 23(1): 384, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872489

RESUMO

OBJECTIVES: This study aimed to investigate the differences in the effectiveness of percutaneous radiofrequency thermocoagulation (PRT) and microvascular decompression (MVD) in treating glossopharyngeal neuralgia (GPN). METHODS: Medical records of patients were reviewed to investigate their baseline characteristics and immediate postoperative prognosis. Long-term outcomes of these patients were obtained through telephone interviews. Visual analog scale (VAS) and Pittsburgh sleep quality index (PSQI) scores at 1 day and 1, 4, 12, 24, and 48 weeks after surgery were compared between the MVD and PRT groups, in addition to complete pain relief rate, effective rate, adverse reactions, length of hospital stay, and economic indicators. RESULTS: The VAS and PSQI scores of the two groups at 1 day and 1, 4, 12, 24, and 48 weeks after surgery were significantly lower (P < 0.05) than those before surgery. At 48 weeks, the complete remission rate was significantly higher (P < 0.05) in the MVD group than in PRT group. No significant difference in adverse reactions was observed between the two groups. The length of hospital stay, operative time, and cost were significantly higher (P < 0.05) in the MVD group than in the PRT group. CONCLUSIONS: Both PRT and MVD can significantly reduce patients' degree of pain and improve their sleep quality. In the medium term, MVD is better than PRT in terms of the complete curative effect. In young patients with GPN, MVD is more often recommended than PRT; however, MVD is costlier than PRT.


Assuntos
Doenças do Nervo Glossofaríngeo , Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Doenças do Nervo Glossofaríngeo/cirurgia , Doenças do Nervo Glossofaríngeo/etiologia , Eletrocoagulação , Dor/etiologia , Neuralgia do Trigêmeo/cirurgia
5.
J Environ Sci (China) ; 130: 126-138, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37032029

RESUMO

Estimating intercity vehicle emissions precisely would benefit collaborative control in multiple cities. Considering the variability of emissions caused by vehicles, roads, and traffic, the 24-hour change characteristics of air pollutants (CO, HC, NOX, PM2.5) on the intercity road network of Guangdong Province by vehicle categories and road links were revealed based on vehicle identity detection data in real-life traffic for each hour in July 2018. The results showed that the spatial diversity of emissions caused by the unbalanced economy was obvious. The vehicle emissions in the Pearl River Delta region (PRD) with a higher economic level were approximately 1-2 times those in the non-Pearl River Delta region (non-PRD). Provincial roads with high loads became potential sources of high emissions. Therefore, emission control policies must emphasize the PRD and key roads by travel guidance to achieve greater reduction. Gasoline passenger cars with a large proportion of traffic dominated morning and evening peaks in the 24-hour period and were the dominant contributors to CO and HC emissions, contributing more than 50% in the daytime (7:00-23:00) and higher than 26% at night (0:00-6:00). Diesel trucks made up 10% of traffic, but were the dominant player at night, contributed 50%-90% to NOX and PM2.5 emissions, with a marked 24-hour change rule of more than 80% at night (23:00-5:00) and less than 60% during daytime. Therefore, targeted control measures by time-section should be set up on collaborative control. These findings provide time-varying decision support for variable vehicle emission control on a large scale.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Emissões de Veículos/análise , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Veículos Automotores , Material Particulado/análise , China , Poluição do Ar/análise
6.
Opt Express ; 30(18): 31539-31549, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242234

RESUMO

One of the persistent obstacles for high-power laser diodes (LDs) has been the catastrophic optical mirror damage (COMD), which limits the operating power level and lifetime of commercial high-power LDs. The output facet of LD reaches a critical temperature resulting in COMD, which is an irreversible device failure. Here, we fabricate multi-section LDs by tailoring the waveguide structure along the cavity that separates the output facet from the heat-generating lasing region. In this method, the LD waveguide is divided into electrically isolated laser and window sections along the cavity. The laser section is pumped at a high current to achieve high output power, and the window is biased at a low current with negligible heat generation. This design restricts the thermal impact of the laser section on the facet, and the window section allows lossless transport of the laser to the output facet. The lasers were operated continuous-wave up to the maximum achievable power. While standard LDs show COMD failures, the multi-section waveguide LDs are COMD-free. Our technique and results provide a pathway for high-reliability LDs, which would find diverse applications in semiconductor lasers.

7.
Opt Express ; 30(12): 21822-21832, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224894

RESUMO

Motivated by the goals of fabricating highly reliable, high performance, and cost-efficient self-powered photodetector (PD) for numerous scientific research and civil fields, an organic-inorganic hybrid solar-blind ultraviolet (UV) PD based on PEDOT: PSS/exfoliated ß-Ga2O3 microwire heterojunction was fabricated by a flexible and cost-effective assembly method. Benefiting from the heterojunction constructed by the highly crystalline ß-Ga2O3 and the excellent hole transport layer PEDOT: PSS, the device presents a high responsivity of 39.8 mA/W at 250 nm and a sharp cut-off edge at 280 nm without any power supply. Additionally, the ultra-high normalized photo-to-dark current ratio (> 104 mW-1cm2) under reverse bias and the superior detectivity of 2.4×1012 Jones at zero bias demonstrate the excellent detection capabilities. Furthermore, the hybrid PD exhibits a rapid rise time (several milliseconds) and high rejection ratio (R250/R365: 5.8 × 103), which further highlights its good spectral selectivity for solar-blind UV. The prominent performance is mainly ascribed to the efficient separation of the photogenerated carriers by the large built-in electric field of the advanced heterojunction. This flexible assembly strategy for solar-blind UV PD combines the advantages of high efficiency, low cost and high performance, providing more potential for PD investigation and application in the future.

8.
Molecules ; 27(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35164121

RESUMO

Due to the remarkable anti-tumor activities of oridonin (Ori), research on Rabdosia rubescens has attracted more and more attention in the pharmaceutical field. The purpose of this study was to extract Ori from R. rubescens by ultrasound-assisted extraction (UAE) and prepare Ori liposomes as a novel delivery system to improve the bioavailability and biocompatibility. Response surface methodology (RSM), namely Box-Behnken design (BBD), was applied to optimize extraction conditions, formulation, and preparation process. The results demonstrated that the optimal extraction conditions were an ethanol concentration of 75.9%, an extraction time of 35.7 min, and a solid/liquid ratio of 1:32.6. Under these optimal conditions, the extraction yield of Ori was 4.23 mg/g, which was well matched with the predicted value (4.28 mg/g). The optimal preparation conditions of Ori liposomes by RSM, with an ultrasonic time of 41.1 min, a soybean phospholipids/drug ratio of 9.6 g/g, and a water bath temperature of 53.4 °C, had higher encapsulation efficiency (84.1%). The characterization studies indicated that Ori liposomes had well-dispersible spherical shapes and uniform sizes with a particle size of 137.7 nm, a polydispersity index (PDI) of 0.216, and zeta potential of -24.0 mV. In addition, Ori liposomes presented better activity than free Ori. Therefore, the results indicated that Ori liposomes could enhance the bioactivity of Ori, being proposed as a promising vehicle for drug delivery.


Assuntos
Diterpenos do Tipo Caurano , Isodon/química , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacocinética , Diterpenos do Tipo Caurano/farmacologia , Humanos , Lipossomos , Células MCF-7 , Tamanho da Partícula
9.
Biomed Chromatogr ; 33(12): e4677, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31396971

RESUMO

An efficient ultra-performance liquid chromatography with diode-array detector method was established for simultaneous determination of six active components in Roukou Wuwei pills, namely gallic acid, piperine, costundide, dehydrocostus lactone, isoalantolactone and alantolactone. Chromatographic separation of six components was successfully achieved on an Waters BEH C18 column (50 × 2.1 mm, 1.7 µm) with a mobile phase composed of acetonitrile and water using a gradient elution. Gallic acid and piperine were detected at 270 nm and 343 nm, respectively; while costundide, dehydrocostus lactone, isoalantolactone and alantolactone were simultaneously measured at 225 nm. All six calibration curves showed good linearity (R2 ≥ 0.9994) between the peak area of each component and corresponding concentration. Relative standard deviations for inter- and intra-day precisions were <0.45 and 0.77%, respectively. The mean recovery rates ranged from 96.72 to 102.2% with relative standard deviations <2.07%. The developed method was validated in terms of linearity, precision and accuracy and then successfully applied for the quality control of commercial Roukou Wuwei samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Alcaloides/análise , Benzodioxóis/análise , Ácido Gálico/análise , Lactonas/análise , Limite de Detecção , Modelos Lineares , Piperidinas/análise , Alcamidas Poli-Insaturadas/análise , Reprodutibilidade dos Testes , Sesquiterpenos/análise
10.
Pharmazie ; 74(10): 590-594, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685082

RESUMO

Inclusion complexes of essential oils with cyclodextrins are an effective way to improve stability and solubility, and turn liquid materials into easy to handle powders. In this work, an essential oil of Myristica fragrans Hott. (MFEO), already used in the food and cosmetics industries, was formulated with beta-cyclodextrins (ß-CD) using a co-precipitation method. The orthogonal array scheme was adapted for the optimization of preparation process. DSC and FT-IR spectroscopy analysis indicated the successful formation of MFEO/ß-CD inclusion complexes, which improved the thermal stability of MFEO. Furthermore, comparing the antimicrobial activity of MFEO/ß-CD inclusion complexes and free essential oil against Staphyloccocus aureus, Staphyloccocus epidermidis, Escherichia coli, Klebsiella pneumoniae, yeast Saccharomyces cerevisiae and Bacillus subtilis, it was found that the antimicrobial effect was enhanced after the formation of inclusion complexes. This study demonstrates the potential for the use of MFEO/ß-CD inclusion complexes in the treatment of bacterial infection.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Myristica/química , Óleos Voláteis/química , beta-Ciclodextrinas/química , Bacillus subtilis , Escherichia coli , Klebsiella pneumoniae , Óleos Voláteis/farmacologia , Saccharomyces cerevisiae , Staphylococcus aureus , Staphylococcus epidermidis , beta-Ciclodextrinas/farmacologia
11.
Int J Med Sci ; 15(6): 580-586, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29725248

RESUMO

Breast cancer is a major cause of cancer mortality worldwide. High-mobility group box protein 1 (HMGB1) is a ubiquitous nuclear protein found in all mammal eukaryotic cells that participates in tumor progression, migration and metastasis. HMGB1 overexpression has been indicated in breast cancer patients. However, scant information is available regarding the association between HMGB1 single nucleotide polymorphisms (SNPs) and the risk or prognosis of breast cancer. We report on the association between 4 SNPs of the HMGB1 gene (rs1360485, rs1045411, rs2249825 and rs1412125) and breast cancer susceptibility as well as clinical outcomes in 313 patients with breast cancer and in 217 healthy controls. Patients with one G allele in the rs1360485 or rs2249825 domains are likely to progress to T2 tumor and lymph node metastasis. In addition, the presence of one G allele in SNPs rs1360485 or rs2249825 was associated with a higher risk of progressing to T2 tumor and distant metastasis amongst HER2-enriched and triple-negative breast cancer (TNBC) tumors compared with luminal A and luminal B tumors. Furthermore, having one C allele in the rs1412125 domain increased the risk of pathologic grade 3 disease in HER2-enriched and TNBC tumors. Our results indicate that genetic variations in the HMGB1 gene may serve as an important predictor of breast cancer progression and metastasis.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Proteína HMGB1/genética , Adulto , Alelos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Progressão da Doença , Feminino , Genótipo , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Receptor ErbB-2/genética , Fatores de Risco
12.
Int J Med Sci ; 15(11): 1179-1186, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123055

RESUMO

Breast cancer is a major cause of cancer mortality amongst women. Chemokine (C-C motif) ligand 4 is encoded by the CCL4 gene; specific CCL4 gene polymorphisms are related to the risks and prognoses of various diseases. In this study, we examined whether CCL4 gene single nucleotide polymorphisms (SNPs) predict the risk and progression of breast cancer. Between 2014 and 2016, we recruited 314 patients diagnosed with breast cancer and a cohort of 209 healthy participants (controls) without a history of cancer. Genotyping of the CCL4 rs1634507, rs10491121 and rs1719153 SNPs revealed no significant between-group differences for these polymorphisms. However, amongst luminal A and luminal B subtypes, compared with patients with the AA genotype, those carrying the AG genotype at SNP rs10491121 were less likely to develop lymph node metastasis. In addition, compared with AA carriers, those carrying the AG + GG genotype at SNP rs10491121 were at lower risk of developing distant metastasis, while the presence of the AT genotype at SNP rs1719153 increased the likelihood of pathologic grade (G3 or G4) disease. Variations in the CCL4 gene may help to predict breast cancer progression and metastasis.


Assuntos
Neoplasias da Mama/genética , Quimiocina CCL4/genética , Metástase Linfática , Polimorfismo de Nucleotídeo Único , Adulto , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Progressão da Doença , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Adulto Jovem
13.
J Sci Food Agric ; 96(13): 4484-91, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26858003

RESUMO

BACKGROUND: Tricholoma mongolicum Imai is a well-known edible and medicinal mushroom which in recent years has attracted increasing attention because of its bioactivities. In this study, water-soluble polysaccharides were extracted from T. mongolicum Imai by cellulase-assisted extraction and their antioxidant activities were investigated. RESULTS: In order to improve the yield of polysaccharides, four variables, cellulase amount (X1 ), pH (X2 ), temperature (X3 ) and extraction time (X4 ), were investigated with a Box-Behnken design. The optimal conditions were predicted to be cellulase amount of 20 g kg(-1) , pH of 4.0, temperature of 50 °C and extraction time of 127 min, with a predicted polysaccharide yield of 190.1 g kg(-1) . The actual yield of polysaccharides under these conditions was 189.6 g kg(-1) , which matched the predicted value well. The crude polysaccharides were purified to obtain four fractions, and characterization of each was carried out. In addition, antioxidant properties of four polysaccharides assessed by 1,1-diphenyl-2-picryldydrazyl (DPPH) and hydroxyl radical-scavenging assays indicated that polysaccharides from T. mongolicum Imai (TMIPs) possessed antioxidant activity in a dose-dependent manner. CONCLUSION: TMIPs show moderate antioxidant activities in vitro. Therefore it is suggested that TMIPs are potential natural antioxidants for use in functional foods. © 2016 Society of Chemical Industry.


Assuntos
Antioxidantes/isolamento & purificação , Celulase/metabolismo , Misturas Complexas/isolamento & purificação , Aditivos Alimentares/isolamento & purificação , Carpóforos/química , Polissacarídeos Fúngicos/isolamento & purificação , Tricholoma/química , Algoritmos , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Sequência de Carboidratos , China , Misturas Complexas/biossíntese , Misturas Complexas/química , Aditivos Alimentares/análise , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Alimentos em Conserva/análise , Alimentos em Conserva/economia , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Carpóforos/metabolismo , Polissacarídeos Fúngicos/análise , Polissacarídeos Fúngicos/biossíntese , Polissacarídeos Fúngicos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Químicos , Peso Molecular , Estatística como Assunto , Fatores de Tempo , Tricholoma/metabolismo
14.
Medicine (Baltimore) ; 103(38): e39739, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39312312

RESUMO

To observe the effect of low temperature plasma ablation combined with collagenase injection on lumbar disc herniation. 90 patients with lumbar disc herniation admitted to the pain department of our hospital and receiving surgical treatment from April 2021 to April 2023 were included in this retrospective study, and were divided into 2 groups according to different treatment plans. One group was treated with low-temperature plasma ablation combined with collagenase injection, and the other group was treated with low-temperature plasma ablation alone. The sample size of both groups was 80 cases. Peripheral blood was collected by fasting in the morning at 5 time points before surgery, 1, 3, 7 and 14 days after surgery, and 5 mL of whole venous blood was collected by disposable vacuum blood collection device. Serum levels of pro-inflammatory factor interleukin (IL)-1α, IL-1ß, IL-6, IL-8, tumor necrosis factor-α and anti-inflammatory factor IL-4, IL-10 were detected by ELISA. VAS scores were used to evaluate postoperative low back pain. ODI and Lehmann Lumbar Function Scale were used to evaluate postoperative lumbar function. The contents of IL-1α, IL-1ß, IL-6, IL-8, tumor necrosis factor-α and anti-inflammatory factor IL-4, IL-10 in the cryo-plasma ablation combined with collagenase injection group were significantly lower than those in the cryo-plasma ablation group alone (P < .05). The VAS score of cryo-plasma ablation combined with collagenase injection group was significantly lower than that of cryo-plasma ablation group at 1 day and 3 months after treatment, and the difference was statistically significant (P < .05). The ODI score of cryo-plasma ablation combined with collagenase injection group was significantly lower than that of cryo-plasma ablation group at 1 day and 3 months after treatment, and the difference was statistically significant (P < .05). The Lehmann score of cryo-plasma ablation combined with collagenase injection group was significantly higher than that of cryo-plasma ablation group at 1 day and 3 months after treatment, and the difference was statistically significant (P < .05). The overall efficacy of low-temperature plasma ablation combined with collagenase injection is better than that of low-temperature plasma ablation alone. Low temperature plasma ablation combined with collagenase injection in the treatment of patients with lumbar disc herniation has less pain, faster recovery.


Assuntos
Colagenases , Deslocamento do Disco Intervertebral , Vértebras Lombares , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Colagenases/administração & dosagem , Colagenases/uso terapêutico , Adulto , Vértebras Lombares/cirurgia , Terapia Combinada , Resultado do Tratamento , Medição da Dor , Dor Lombar/terapia , Dor Lombar/etiologia , Técnicas de Ablação/métodos
15.
Sci Total Environ ; 949: 175176, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39094657

RESUMO

The rapid progress of intelligent transportation systems (ITS) has enabled the development of a highly spatiotemporally resolved vehicular VOC emission inventory. However, up to this point, the emission factors applied in vehicular VOC emission inventories worldwide are either independent of driving conditions or estimated by emission models, resulting in significant bias. In this study, by using the speed-dependent VOC emission factor measured online from a typical fleet in Guangzhou and collecting multiple sources of ITS data, we developed, for the first time, a link-level dynamic vehicular VOC emission inventory. The results reveal that the emission factors for vehicles at speeds higher than 50 km/h are only around 30 % of those at 5-20 km/h. Consequently, the total vehicular VOC emission in Guangzhou is estimated to be 16.19 kt in 2019, around 40 % lower than the estimates by the static emission inventory using the average emission factor during a short transient driving (STD) cycle. This discrepancy is mainly due to the much lower average speed of the STD cycle (20 km/h) compared to the average traffic speed on the road network (36 km/h). The discrepancy in VOC emissions was even higher for highways, with the static emission factors being 75-93 % higher than the speed-dependent ones. Such a large discrepancy underscores the necessity of applying localised speed-dependent emission factors to improve the estimation accuracy of vehicular VOC emissions. This study provides more accurate insights for policymakers in formulating targeted strategies to reduce vehicular VOC emissions and mitigate their contributions to ozone and PM2.5 pollution in urban areas.

16.
J Hazard Mater ; 468: 133780, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401213

RESUMO

Chemically durable and effective adsorbents for radiotoxic TeOx2- (TeIV and TeVI) anions remain in great demand for contamination remediation. Herein, a low-cost iron-based metal-organic framework (MIL-101(Fe)) was used as an adsorbent to capture TeOx2- anions from contaminated solution with ultrafast kinetics and record-high adsorption capacity of 645 mg g-1 for TeO32- and 337 mg g-1 for TeO42-, outperforming previously reported adsorbents. Extended X-ray absorption fine structure (EXAFS) and density functional theory (DFT) calculations confirmed that the capture of TeOx2- by MIL-101(Fe) was mediated by the unique C-O-Te and Fe-O-Te coordination bonds at corresponding optimal adsorption sites, which enabled the selective adsorption of TeOx2- from solution and further irreversible immobilization under the geological environment. Meanwhile, MIL-101(Fe) works steadily over a wide pH range of 4-10 and at high concentrations of competing ions, and it is stable under ß-irradiation even at high dose of 200 kGy. Moreover, the MIL-101(Fe) membrane was fabricated to efficiently remove TeO32- ions from seawater for practical use, overcoming the secondary contamination and recovery problems in powder adsorption. Finally, the good sustainability of MIL-101(Fe) was evaluated from three perspectives of technology, environment, and society. Our strategy provides an alternative to traditional removal methods that should be attractive for Te contamination remediation.

17.
Int J Biol Macromol ; 278(Pt 3): 134947, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39173803

RESUMO

This study aimed to optimize the extraction of Hericium erinaceus polysaccharides (HEP) using ultrasound-assisted enzymatic extraction combined with Plackett-Burman design (PBD) and response surface methodology (RSM). The optimal extraction conditions were identified as: 33 min extraction time, 30:1 liquid to material ratio, 38 °C extraction temperature, 9 g/kg cellulase amount, pH 4, and 20 % ethanol concentration. Under these conditions, the extraction yield of HEP was 5.87 ± 0.16 %, consistent with the predicted results. Additionally, the potential immunomodulatory activity of HEP on RAW 264.7 macrophage was evaluated. The results revealed that HEP improved the immunostimulatory activity of RAW264.7 cells, evident from increased production of IL-6 and TNF-α. These findings suggest that HEP is capable of enhancing the immune activity of RAW 264.7 macrophage.


Assuntos
Hericium , Macrófagos , Camundongos , Animais , Células RAW 264.7 , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Hericium/química , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/isolamento & purificação , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/química , Agentes de Imunomodulação/isolamento & purificação , Fator de Necrose Tumoral alfa/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Interleucina-6/metabolismo
18.
ScientificWorldJournal ; 2013: 157527, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24089600

RESUMO

Ultrasound-assisted extraction (UAE) of phenolic compounds from Inula helenium was studied. Effects of ethanol concentration, ultrasonic time, solid-liquid ratio, and number of extractions were investigated. An orthogonal array was constructed to optimize UAE process. The optimized extraction conditions were as follows: ethanol concentration, 30%; solid-liquid ratio, 1 : 20; number of extractions, 2 times; extraction time, 30 min. Under the optimal conditions, the yield of total phenolic compounds and chlorogenic acid was 6.13 ± 0.58 and 1.32 ± 0.17 mg/g, respectively. The results showed that high amounts of phenolic compounds can be extracted from I. helenium by ultrasound-assisted extraction technology.


Assuntos
Inula/química , Fenóis/química , Extratos Vegetais/química , Ultrassom , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação
19.
Front Neurol ; 14: 1178335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745662

RESUMO

Objective: This study aimed to systematically assess the efficacy and complications of radiofrequency thermocoagulation (RFT) and percutaneous balloon compression (PBC) for treating trigeminal neuralgia (TN). Methods: Chinese and English studies on RFT and PBC in the treatment of TN were systematically searched using CNKI, Wanfang Data, VIP, PubMed, EMBASE, Cochrane Library, and until December 31, 2022. Further, the literature was strictly screened using specific inclusion and exclusion criteria. The RevMan 5.4 software was used for data processing and meta-analysis. Results: Overall, 16 studies with 3,326 patients were included. The results of meta-analysis revealed that no significant difference was present between the two groups in terms of the rate of efficacy immediately after surgery, 1 month after surgery, and 3 months after surgery (odds ratio [OR] = 0.73, 95% confidence interval [CI] 0.35-1.54, p = 0.41; OR = 0.41, 95% CI 0.13-1.32, p = 0.13; OR = 0.40, 95% CI 0.10-1.60, p = 0.20); however, at 12 months after surgery, the difference was statistically significant (OR = 0.27, 95% CI 0.10-0.75, p = 0.01). Notably, there was no significant difference in the postoperative sleep quality index between the two groups immediately after surgery and 1 month after surgery (SMD = -0.01, 95% CI -2.47 to 2.44, p = 0.99; SMD = 0.14, 95% CI -3.95 to 4.22, p = 0.95). Further, statistically significant differences were observed between the two groups in the incidence of postoperative masticatory muscle strength decline and oral herpes (OR = 0.37; 95% CI 0.21-0.63, p = 0.0003; OR = 0.25, 95% CI 0.10-0.61, p = 0.003). In addition, a statistically significant difference was found in the recurrence rate at 1-year follow-up (OR = 2.23, 95% CI 1.03-4.81, p = 0.04); however, no statistically significant differences were found in the recurrence rate at the 2-year follow-up (OR = 1.95, 95% CI 0.33-11.59, p = 0.46). Conclusion: In the treatment of TN, both RFT and PBC can achieve good short-term efficacy, and no significant differences were noted between the outcomes of the two approaches. Compared with RFT, PBC may result in a lower pain score and recurrence rate in the medium and long terms, but it is a higher incidence of cold sores, and the decrease of masticatory muscle strength is more obvious.

20.
Nanomaterials (Basel) ; 13(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36986014

RESUMO

Low threshold current and polarization-stabilized 795 nm vertical-cavity surface-emitting lasers (VCSELs) are fabricated by integrating a surface grating of high polarization selectivity and high reflectivity. The rigorous coupled-wave analysis method is used to design the surface grating. For the devices with a grating period of 500 nm, a grating depth of ~150 nm, and a diameter of the surface grating region of 5 µm, a threshold current of 0.4 mA and an orthogonal polarization suppression ratio (OPSR) of 19.56 dB are obtained. The emission wavelength of 795 nm of a single transverse mode VCSEL is achieved at a temperature of 85 °C under an injection current of 0.9 mA. In addition, experiments demonstrate that the threshold and output power also depended on the size of the grating region.

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