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1.
Clin Cosmet Investig Dermatol ; 17: 931-940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38689755

RESUMO

Background: Previous observational studies have found that lichen sclerosus (LS) is associated with metabolic statuses, such as diabetes mellitus (DM) and body mass index (BMI). However, there are also some studies showing that LS is not related to DM and BMI. The mechanism behind observational results is still unclear. Therefore, the causality of this relationship remains unknown. In this study, a bidirectional two-sample Mendelian randomization (MR) was conducted to investigate the correlation between DM, BMI, and LS. Methods: The instrumental variables related to DM (including type 1 and type 2 diabetes), and BMI were identified from genome-wide association studies (GWAS) and a GWAS meta-analysis. The GWAS data for LS was from obtained the eighth edition of the FinnGen biological database released in 2022. Inverse variance weighted (IVW), weighted median, and MR-Egger methods were used to conduct a bidirectional two-sample MR analysis. Thereafter, the heterogeneity and horizontal pleiotropy were examined to determine whether the results were affected by a single-nucleotide polymorphism (SNP). Results: We found a lack of evidence for the causal association of DM, and BMI on LS in inverse variance weighted (type 1 diabetes, OR=0.97, 95% CI=0.91-1.04, p=0.429; type 2 diabetes, OR=0.91, 95% CI=0.82-1.00, p=0.0511; BMI, OR=0.92, 95% CI=0.73-1.15, p=0.4554). In the other direction, the results also showed that LS had no significant causal effect on DM and BMI. Conclusion: This MR analysis demonstrated no significant causal relationship between DM and BMI with LS in both directions, which contradicts previous observational studies reporting a positive association. Potential confounding factors may contribute to previously observed associations, and further research is necessary.

2.
Int Immunopharmacol ; 133: 112066, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38615377

RESUMO

Acevaltrate is a natural product isolated from the roots of Valeriana glechomifolia F.G.Mey. (Valerianaceae) and has been shown to exhibit anti-cancer activity. However, the mechanism by which acevaltrate inhibits tumor growth is not fully understood. We here demonstrated the effect of acevaltrate on hypoxia-inducible factor-1α (HIF-1α) expression. Acevaltrate showed a potent inhibitory activity against HIF-1α induced by hypoxia in various cancer cells. This compound markedly decreased the hypoxia-induced accumulation of HIF-1α protein dose-dependently. Further analysis revealed that acevaltrate inhibited HIF-1α protein synthesis and promoted degradation of HIF-1α protein, without affecting the expression level of HIF-1α mRNA. Moreover, the phosphorylation levels of mammalian target of rapamycin (mTOR), ribosomal protein S6 kinase (p70S6K), and eIF4E binding protein-1 (4E-BP1) were significantly suppressed by acevaltrate. In addition, acevaltrate promoted apoptosis and inhibited proliferation, which was potentially mediated by suppression of HIF-1α. We also found that acevaltrate administration inhibited tumor growth in mouse xenograft model. Taken together, these results suggested that acevaltrate was a potent inhibitor of HIF-1α and provided a new insight into the mechanisms of acevaltrate against cancers.


Assuntos
Apoptose , Proliferação de Células , Subunidade alfa do Fator 1 Induzível por Hipóxia , Serina-Treonina Quinases TOR , Valeriana , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Humanos , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Valeriana/química , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos , Camundongos Nus , Camundongos Endogâmicos BALB C , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico
3.
Small ; : e2311249, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38482932

RESUMO

Host-guest catalyst provides new opportunities for targeted applications and the development of new strategies for preparing host-guest catalysts is highly desired. Herein, an in situ solvent-free approach is developed for implanting ZrW2 O7 (OH)2 (H2 O)2 nanorods (ZrW-NR) in nitro-functionalized UiO-66(Zr) (UiO-66(Zr)-NO2 ) with hierarchical porosity, and the encapsulation of ZrW-NR enables the as-prepared host-guest catalyst remarkably enhanced catalytic performance for both for oxidative desulfurization (ODS) and acetalization reactions. ZrW-NR@UiO-66(Zr)-NO2 can eliminate 500 ppm sulfur within 9 min at 40 °C in ODS, and can transform 5.6 mmol benzaldehyde after 3 min at room temperature in acetalization reaction. Its turnover frequencies reach 72.3 h-1 at 40 °C for ODS which is 33.4 times higher than UiO-66(Zr)-NO2 , and 28140 h-1 for acetalization which is the highest among previous reports. Density functional theory calculation result indicates that the W sites in ZrW-NR can decompose H2 O2 to WVI -peroxo intermediates that contribute to catalytic activity for the ODS reaction. This work opens a new solvent-free approach for preparing MOFs-based host-guest catalysts to upgrade their redox and acid performance.

4.
Eur Arch Psychiatry Clin Neurosci ; 274(2): 433-443, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37400684

RESUMO

BACKGROUND: Dopamine receptor D2 (DRD2) TaqIA polymorphism has an influence on addiction treatment response and prognosis by mediating brain dopaminergic system efficacy. Insula is crucial for conscious urges to take drugs and maintain drug use. However, it remains unclear about the contribution of DRD2 TaqIA polymorphism to the regulation of insular on addiction behavioral and its relation with the therapeutic effect of methadone maintenance treatment (MMT). METHODS: 57 male former heroin dependents receiving stable MMT and 49 matched male healthy controls (HC) were enrolled. Salivary genotyping for DRD2 TaqA1 and A2 alleles, brain resting-state functional MRI scan and a 24-month follow-up for collecting illegal-drug-use information was conducted and followed by clustering of functional connectivity (FC) patterns of HC insula, insula subregion parcellation of MMT patients, comparing the whole brain FC maps between the A1 carriers and non-carriers and analyzing the correlation between the genotype-related FC of insula sub-regions with the retention time in MMT patients by Cox regression. RESULTS: Two insula subregions were identified: the anterior insula (AI) and the posterior insula (PI) subregion. The A1 carriers had a reduced FC between the left AI and the right dorsolateral prefrontal cortex (dlPFC) relative to no carriers. And this reduced FC was a poor prognostic factor for the retention time in MMT patients. CONCLUSION: DRD2 TaqIA polymorphism affects the retention time in heroin-dependent individuals under MMT by mediating the functional connectivity strength between left AI and right dlPFC, and the two brain regions are promising therapeutic targets for individualized treatment.


Assuntos
Dependência de Heroína , Heroína , Humanos , Masculino , Heroína/uso terapêutico , Córtex Pré-Frontal Dorsolateral , Polimorfismo Genético/genética , Dependência de Heroína/diagnóstico por imagem , Dependência de Heroína/tratamento farmacológico , Dependência de Heroína/genética , Metadona/uso terapêutico , Imageamento por Ressonância Magnética , Receptores de Dopamina D2/genética
5.
Int J Gynaecol Obstet ; 165(2): 672-676, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38146751

RESUMO

OBJECTIVE: This study examined the quality of life and burden of disease of vulvar lichen sclerosus (VLS) patients in three states of menstruation to better understand VLS. METHODS: A total of 607 VLS patients were enrolled into this retrospective study. According to the ages of onset, menarche and menopause, the patients were divided into three groups: prepubertal group (n = 96), reproductive group (n = 400) and postmenopausal group (n = 111). Data were collected by direct interview and clinical examination. RESULTS: A total of 93% of patients had itching, with a median numerical rating scale score of five. In the prepubertal group, the median score was three. Nocturnal itching occurred in 49.6% patients. Nearly half of the patients (45.9%) thought the itching affected their sleep. However, this ratio was very different in the prepubertal group (20.7%). Some patients (12.8%) cleaned their vulva more than seven times per week. Only 17.2% of patients experienced no effect on their sex life. The median dermatology life quality index score in all patients was six, but it was only three in the prepubertal group. The median number of hospital visits was two times, and the number of clinic visits was three times. Previous expenses, in median, were 2000 RMB. For 84.3% patients, the gynecologic clinic was their first choice. CONCLUSION: VLS places great physical, mental and economic burdens on patients. Patients in the prepubertal group had milder symptoms and dermatology life quality index score. VLS should arouse the attention of patients and specialists.


Assuntos
Líquen Escleroso Vulvar , Humanos , Feminino , Líquen Escleroso Vulvar/epidemiologia , Estudos Retrospectivos , Qualidade de Vida , China/epidemiologia , Prurido , Efeitos Psicossociais da Doença
6.
Phys Chem Chem Phys ; 26(2): 1293-1302, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38105747

RESUMO

III-V/Si multi-junction solar cells have been widely studied in recent years due to their excellent theoretical efficiency (∼42%). In order to solve the problem of lattice mismatch between Si and III-V compounds of III-V/Si solar cells, different hexagonal Si1-xGex buffer layer models on the surface of hexagonal diamond Si(001) were built, and the structural, electronic and optical properties of the proposed models were calculated based on first principles calculations. The results showed that all models of the designed buffer layer could effectively reduce the lattice mismatch, and the buffer layer hex-Si1-xGex (x = 0, 0.75, and 1) is the ideal model and has achieved the best lattice-matching improvement with high defect formation energy, as well as direct band gap properties and a larger light adsorption coefficient. These theoretical models, with their analyzed properties, could offer a promising pathway toward realizing high efficiency and low cost III-V/Si multi-junction solar cells.

7.
Clin Cosmet Investig Dermatol ; 16: 3625-3628, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38144160

RESUMO

Interstitial granulomatous drug reaction (IGDR) is a drug-related disease with distinctive clinical and histopathological features uncommon in clinical practice. Chemotherapeutics-related IGDR has rarely been reported. Here, we describe one case of interstitial granulomatous drug reaction due to chemotherapy.

8.
RSC Adv ; 13(48): 33644-33653, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38020032

RESUMO

2-Amino-2-methyl-1-propanol (AMP) is often used as a moderator to enhance the CO2 capture capacity of absorbents due to its unique spatial site resistance structure, and relatively few studies have been conducted on the enhancement of AMP aqueous solutions by nanoparticles for CO2 capture. In order to investigate the effect of nanoparticles on the CO2 capture performance of AMP aqueous solution, different nanofluids were formulated in this paper using a two-step method, and a bubbling reactor and an oil bath were used as the experimental setup for absorption/desorption, and through comparative experiments, it was found that the type of nanoparticles, the solid content, and the different parameters have great influences on the CO2 absorption load and desorption rate. The experimental results show that the addition of TiO2 nanoparticles to the AMP base solution can accelerate the absorption-desorption mass transfer rate of CO2, and there exists an optimal solid content of 1 g L-1 (±1.0%, ±2.5%); after multiple absorption-desorption experiments, good cycling performance can still be achieved. The experimental results of the nanofluid-promoted mass transfer mechanism are also illustrated and analyzed in this paper.

9.
RSC Adv ; 13(48): 33852-33862, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38020038

RESUMO

Catalytic co-pyrolysis of coal and biomass can improve both solid waste utilization and high value-added product content to obtain higher quality oils, which is significant for the clean and efficient use of coal and the expansion of biomass resource utilization. This study focuses on improving the quality of tar and the content of light fractions by catalytic reforming of coal and biomass co-pyrolysis volatiles. Molybdenum-doped MFI-type molecular sieve catalysts (Mo-MFI) were successfully prepared by a hydrothermal method using TPAOH as a structure-directing agent. The synthesized Mo-MFI molecular sieves were then used in the catalytic reforming of volatile fractions from the co-pyrolysis of low-metamorphic coal and biomass. With the help of biomass and catalyst, the co-pyrolysis tar can increase the content of high-value-added products. It was found that the highest tar yield of 11.4% was achieved when 30 wt% of corn stover was added. The utilization of Mo-MFI catalysts leads to a significant increase of 126% in the light oil content of a blended sample tar consisting of 30 wt% corn stover. The catalyst was also highly selective for low-level phenols, increasing the phenol content in the co-pyrolysis tar by 133.8%, 112.2% for cresols, and 88.1% for xylenol. In addition, a possible reaction pathway for the conversion of hydrocarbons to PXC (phenol, cresol, and xylenol) was proposed based on the changes in the components of the tar product after the addition of the catalyst.

10.
Dalton Trans ; 52(43): 15968-15973, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37846746

RESUMO

Insights into the relationship between the crystal structure and activity of metal-organic frameworks (MOFs) are meaningful to investigate the potential properties of pristine MOFs for targeted catalytic reactions. Herein, we develop a high-efficiency method for boosting the oxidative desulfurization (ODS) activity of Ti-MOF in the presence of H+. The ODS activity of pristine Ti-MOF prepared via a solvothermal approach is very poor at a low reaction temperature but can be enhanced in the presence of H+. Ti-MOF in the presence of H+ shows ultrahigh ODS activity that can eliminate 1000 ppm sulfur after 7 min at 30 °C with no catalytic activity loss after recycling 11 times. The turnover frequency value reaches 12.4 h-1 at 30 °C, surpassing all the previously reported Ti-MOFs as ODS catalysts even at high temperatures. Characterization and quenching experimental results indicate that more uncoordinated Ti sites can be formed from slight damage to the structure of Ti-MOF during the catalytic reaction, and such exposed Ti sites can easily react with H+ and H2O2 to form Ti-hydroperoxo active species that determine the upgradation of ODS activity. This work provides a significant way to upgrade the catalytic activity of pristine Ti-MOFs for future application.

11.
JAMA Dermatol ; 159(10): 1059-1067, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37585188

RESUMO

Importance: There are limited prognostic statistics and data available on survival outcomes for patients with mycosis fungoides (MF) in Asia. Objective: To determine the prognostic factors and survival outcomes of patients with MF among a cohort in China. Design, Setting, and Participants: This was a retrospective cohort study of patients with MF who received treatment at a tertiary referral center for skin lymphoma (Peking University First Hospital, Beijing, China) from August 1, 2009, to August 31, 2021. Data were analyzed from September 1, 2021, to December 31, 2022. Main Outcomes and Measures: Overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS); for prognostic factors, hazard ratios (HRs), and adjusted HRs (aHRs; adjusted for sex, age, and overall TNMB [tumor, node, metastasis, blood] stage) determined using the Cox proportional hazards model. Results: The study cohort comprised 461 patients with MF (median [range] age at diagnosis, 46 [5-87] years; 275 [59.7%] men and 186 [40.3%] women; 461 [100%] Chinese). The overall 5-year rate was 82.2% for OS, 83.5% for DSS, and 79.6% for PFS. Stage-specific 5-year OS rates were 95.7% for stage IA, 93.2% for IB, 95.7% for IIA, 70.1% for IIB, 55.3% for III, and 23.6% for IV. Compared with a UK cohort, our Chinese cohort had a younger median age at diagnosis (46 years vs 54 years) and a more favorable 5-year OS (82.2% vs 75.0%); however, after adjusting for age, the discrepancy in the 5-year OS rate was diminished (77.3% vs 76.4%). Cox models revealed that unfavorable predictors of OS, PFS, and DSS, respectively, were: age older than 60 years (aHR [95% CI], 2.25 [1.28-3.96]; 2.09 [1.16-3.76]; 2.27 [1.39-3.72]); advanced TNMB stage; advanced overall stage; large-cell transformation (aHR [95% CI], 2.16 [1.17-3.99]; 2.29 [1.21-4.33]; 2.21 [1.26-3.86]); and elevated lactate dehydrogenase levels (aHR [95% CI], 3.92 [1.64-9.36]; 4.77 [1.86-12.22]; 5.05 [2.23-11.42]). Biological sex and plaque lesion type were not associated with prognosis among this study cohort. Conclusion and Relevance: The findings of this retrospective cohort study of patients with MF in China suggest that Asian patients are diagnosed at a younger age and have a higher 5-year OS compared with patients of other races in studies in other countries (predominantly White). Prognostic factors were similar to those of previous studies, except for patient sex and plaque lesion type.


Assuntos
Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Masculino , Humanos , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Prognóstico , Síndrome de Sézary/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Progressão da Doença , Micose Fungoide/diagnóstico , Neoplasias Cutâneas/patologia , China/epidemiologia
12.
Dalton Trans ; 52(22): 7695-7700, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37200000

RESUMO

Functionalized metal-organic frameworks (MOFs) have been used in a wide range of applications. Although the development of functionalized MOFs with plentiful open metal sites (defects) provides an avenue for targeted reactions, creating such defects remains challenging. Herein, a UiO-type MOF with hierarchical porosity and plentiful Zr-OH/OH2 sites (capping 35% Zr coordination sites) was synthesized within 40 min by a solid-phase synthesis route without the use of solvent and template. The optimal sample converted 5.7 mmol benzaldehyde to (dimethoxymethyl)benzene within 2 min at 25 °C. The turnover frequency number and activity per unit mass reached 2380 h-1 and 8568 mmol g-1 h-1, respectively, outperforming all previously reported catalysts at room temperature. This excellent catalytic activity was correlated with the defect density in functionalized UiO-66(Zr) and the accessibility of plentiful Zr-OH/OH2 sites as acid sites.

13.
Small ; 19(38): e2301035, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37226376

RESUMO

Stable platforms of host-guest catalysts are indispensable in the field of heterogeneous catalysis, however, clarifying the specific effect of host remains challenging. Herein, polyoxometalate (POM) is encapsulated in three types of UiO-66(Zr) with different controlled densities of defects by the aperture opening and closing strategy at ambient-temperature. It is found that catalytic activity of POM for oxidative desulfurization (ODS) at room temperature is turned on when encapsulated in the defective UiO-66(Zr), and the sulfur oxidation efficiency shows an obvious increasing trend (from 0.34 to 10.43 mmol g-1 h-1 ) with the increased concentration of defects in UiO-66(Zr) host. The as-prepared catalyst with the most defective host displays ultrahigh performance which removed 1000 ppm sulfur with exceptionally diluted oxidant at room-temperature within 25 min. The turnover frequency can reach 620.0 h-1 at 30 °C, which surpassed all the reported MOFs based ODS catalysts. A substantial guest/host synergistic effect mediated by the defective sites in UiO-66(Zr) is responsible for the enhancement. Density functional theory calculations reveal that OH/OH2 capped on the open Zr sites of host UiO-66(Zr) can decompose H2 O2 to OOH group and enables the formation of WVI -peroxo intermediates that determine the ODS activity.

14.
RSC Adv ; 13(10): 6847-6860, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36865576

RESUMO

X100 steel is easy to be corroded because of the high salt content in alkaline soils. The Ni-Co coating can slow down the corrosion but still cannot meet the requirements of modern demands. Based on this, in this study, on the basis of adding Al2O3 particles to the Ni-Co coating to strengthen its corrosion resistance, combined with superhydrophobic technology to inhibit corrosion, a micro/nano layered Ni-Co-Al2O3 coating with a new combination of cells and papillae was electrodeposited on X100 pipeline steel, and superhydrophobicity was integrated into it using a low surface energy modification method to improve wettability and corrosion resistance. SEM, XRD, XPS, FTIR spectroscopy, contact angle, and an electrochemical workstation were used to investigate the superhydrophobic materials' microscopic morphology, structure, chemical composition, wettability, and corrosion resistance. The co-deposition behavior of nano Al2O3 particles can be described by two adsorption steps. When 15 g L-1 nano Al2O3 particles were added, the coating surface became homogeneous, with an increase in papilla-like protrusions and obvious grain refinement. It had a surface roughness of 114 nm, a CA of 157.9° ± 0.6°, and -CH2 and -COOH on its surface. The corrosion inhibition efficiency of the Ni-Co-Al2O3 coating reached 98.57% in a simulated alkaline soil solution, and the corrosion resistance was significantly improved. Furthermore, the coating had extremely low surface adhesion, great self-cleaning ability, and outstanding wear resistance, which was expected to expand its application in the field of metal anticorrosion.

15.
Inorg Chem ; 62(10): 4248-4259, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36857420

RESUMO

Creation of rich open metal sites (defect) on the nodes of metal-organic frameworks (MOFs) is an efficient approach to enhance their catalytic performance in heterogeneous reactions; however, direct generation of such defects remains challenging. In this contribution, we developed an in situ green route for rapid fabrication of defective MOF-808(Zr) with rich Zr-OH/OH2 sites (occupying 25% Zr coordination sites) and hierarchical porosity without the assistance of formic acid and solvent. The optimal MOF-808(Zr) not only displayed superior activity in oxidative desulfurization (ODS) for removing 1000 ppm sulfur at ambient temperature within 20 min but also could convert 3.8 mmol of benzaldehyde to (dimethoxymethyl)benzene within 90 s at 30 °C. The turnover frequencies reached 45.4 h-1 for ODS and 3451 h-1 for acetalization, outperforming the most reported MOF-based catalysts. Theoretical calculation and experimental results show that the formed Zr-OH/OH2 can react with H2O2 to generate peroxo-zirconium species, which readily oxidize the sulfur compound. Our work provides a new approach to the synthesis of defect-rich MOF-808(Zr) with the accessibility of active sites for target reactions.

16.
Appl Microbiol Biotechnol ; 107(9): 2771-2781, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36971794

RESUMO

Chinese hamster ovary (CHO) cells can produce proteins with complex structures and post-translational modifications which are similar to human-derived cells, and they have been the ideal host cells for the production of recombinant therapy proteins (RTPs). Nearly 70% of approved RTPs are produced by CHO cells. In recent years, a series of measures have been developed to increase the expression of RTPs to achieve the lower production cost during the process of large-scale industrial production of recombinant protein in CHO cells. Among of them, the addition of small molecule additives in the culture medium can improve the expression and production efficiency of recombinant proteins, and has become an effective and simple method. In this paper, the characteristics of CHO cells, the effect and mechanism of small molecule additives are reviewed. KEY POINTS: • Small molecular additives on the expression of RTPs in CHO cells are reviewed • Small molecular additives improve the yield of RTPs • Small molecular additives provide methods for the optimization of serum-free medium.


Assuntos
Processamento de Proteína Pós-Traducional , Cricetinae , Animais , Humanos , Cricetulus , Células CHO , Proteínas Recombinantes/metabolismo
17.
RSC Adv ; 12(34): 21725-21735, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-36043111

RESUMO

Co-pyrolysis experiments with low metamorphic coal (LC) and pine sawdust (PS) were carried out in a fixed-bed pyrolysis reactor. The effect of biomass addition on the yield distribution and composition of the coal pyrolysis products was investigated. The pyrolysis behavior was studied by thermogravimetric analysis. The Coats-Redfern integral and Achar differential methods were used to study the mechanism functions and the kinetic parameters of the pyrolysis process of each sample. The results show that there is a synergistic effect on the co-pyrolysis and it is most pronounced at a PS mixing ratio of 30%, and it results in improved tar and gas yields. Part of the polycyclic aromatic hydrocarbons (PAHs) in the co-pyrolysis tar are converted into phenolic substances with a simple structure, which improves the quality of the tar. At the same time, the alcohols and acids in the PS and LC react to generate a large number of esters. The addition of PS shifted the LC pyrolysis process towards the low temperature region, lowering the pyrolysis temperature of the coal sample and increasing the pyrolysis rate of the sample. The main pyrolysis process of LC conforms to the second-order chemical reaction law with an activation energy of 35.93 kJ mol-1, and the main pyrolysis process of PS conforms to the one-dimensional diffusion parabolic law with an activation energy of 63.84 kJ mol-1, and the main pyrolysis process of LC and PS co-pyrolysis conforms to a second-order chemical reaction law with an activation energy of 86.19 kJ mol-1.

18.
Comput Intell Neurosci ; 2022: 4096383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720896

RESUMO

Natural language generation (NLG) is a core component of machine translation, dialogue systems, speech recognition, summarization, and so forth. The existing text generation methods tend to be based on recurrent neural language models (NLMs), which generate sentences from encoding vector. However, most of these models lack explicit structured representation for text generation. In this work, we introduce a new generative model for NLG, called Tree-VAE. First it samples a sentence from the training corpus and then generates a new sentence based on the corresponding parse tree embedding vector. Tree-LSTM is used in collaboration with the Stanford Parser to retrieve sentence construction data, which is then used to train a conditional discretization autoencoder generator based on the embeddings of sentence patterns. The proposed model is extensively evaluated on three different datasets. The experimental results proved that the proposed model can generate substantially more diverse and coherent text than existing baseline methods.


Assuntos
Idioma , Processamento de Linguagem Natural , Software , Traduções
19.
Rice (N Y) ; 15(1): 25, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35532865

RESUMO

Most agronomic traits of rice (Oryza sativa), such as grain length, are complex traits controlled by multiple genes. Chromosome segment substitution lines (CSSLs) are ideal materials for dissecting these complex traits. We developed the novel rice CSSL 'Z414', which has short, wide grains, from progeny of the recipient parent 'Xihui 18' (an indica restorer line) and the donor parent 'Huhan 3' (a japonica cultivar). Z414 contains four substitution segments with an average length of 3.04 Mb. Z414 displays seven traits that significantly differ from those of Xihui 18, including differences in grain length, width, and weight; degree of chalkiness; and brown rice rate. We identified seven quantitative trait loci (QTL) that are responsible for these differences in an F2 population from a cross between Xihui 18 and Z414. Among these, six QTL (qPL3, qGW5, qGL11, qRLW5, qRLW11, and qGWT5) were detected in newly developed single-segment substitution lines (SSSLs) S1-S6. In addition, four QTL (qGL3, qGL5, qCD3, and qCD5) were detected in S1 and S5. Analysis of these SSSLs attributed the short, wide grain trait of Z414 to qGL11, qGL3, qGL5, and qGW5. Substitution mapping delimited qGL11 within an 810-kb interval on chromosome 11. Sequencing, real time quantitative PCR, and cell morphology analysis revealed that qGL11 might be a novel QTL encoding the cyclin CycT1;3. Finally, pyramiding qGL3 (a = 0.43) and qGL11 (a = - 0.37) led to shorter grains in the dual-segment substitution line D2 and revealed that qGL11 is epistatic to qGL3. In addition, S1 and D2 exhibited different grain sizes and less chalkiness than Z414. In conclusion, the short grain phenotype of the CSSL Z414 is controlled by qGL11, qGL3, and qGL5. qGL11 might be a novel QTL encoding CycT1;3, whose specific role in regulating grain length was previously unknown, and qGL11 is epistatic to qGL3. S1 and D2 could potentially be used in hybrid rice breeding.

20.
Chemosphere ; 302: 134884, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35551937

RESUMO

Volatile organic compounds (VOCs) are the main precursor for ozone formation and hazardous to human health. Light alkane as one of the typical VOCs is difficult to degrade to CO2 and H2O by catalytic degradation method due to its strong C-H bond. Herein, a series of ultrafine Ru nanoclusters (<0.95 nm) enveloped in silicalite-1 (S-1) zeolite catalysts were designed and prepared by a simple one-pot method and applied for catalytic degradation of propane. The results demonstrate that the enveloped Ru1@S-1 catalyst has excellent propane degradation performance. Its T95 is as low as 294 °C with moisture, and the turnover frequency (TOF) value is up to 5.07 × 10-3 s-1, evidently higher than that of the comparison supported catalyst (Ru1/S-1). Importantly, Ru1@S-1 exhibits superior thermal stability, water resistance and recyclability, which should be attributed to the confinement and shielding effect of the S-1 shell. The in-situ DRIFTS result reveals that the propane degradation over Ru1@S-1 follows the Mars-van-Krevelen (MvK) mechanism, where the hydroxy from the framework of zeolite can provide the active oxygen species. Our work provides a new candidate and guideline for an efficient and stable catalyst for the low-temperature degradation of the light alkane VOCs.


Assuntos
Compostos Orgânicos Voláteis , Zeolitas , Alcanos , Catálise , Humanos , Propano , Temperatura , Compostos Orgânicos Voláteis/química , Zeolitas/química
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