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1.
J Am Chem Soc ; 145(12): 6986-6993, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36920250

RESUMO

By means of first-principles theory, existence, synthetic conditions, and structural as well as physicochemical properties have been predicted for the first hydrogen-free melaminate salt of the composition WC3N6. We find at least two energetically favorable polymorphs adopting space groups P1 and P3, both of which are layer-like porous materials. In addition to sizable Madelung fields stabilizing saltlike WC3N6, the complex C3N66- anions are connected via perfectly optimized W-N bonds, forming WN5 in the P1 and WN6 coordination polyhedra in the P3 polymorphs. The band gaps of the P1 and P3 phases are HSE-predicted as 2.25 and 1.21 eV, respectively, significantly smaller than those of g-C3N4 and WO3. Moreover, both phases have suitable band-edge potentials that may provide sufficient driving force for photocatalytic water splitting; at least for the P1 phase, there is also a reasonable chance for reduced electron-hole recombination. In addition, the polymorphs's large optical absorption coefficients should greatly enhance the photocatalytic performance. WC3N6 defines a new class of compounds and has unique structural characteristics, mirrored from its electrical and optical properties, and it should provide another chemical path for preparing efficient photocatalysts and optoelectronic devices.

2.
J Phys Chem A ; 127(44): 9273-9282, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37883703

RESUMO

The development of organic photoluminescent (PL) materials with red-shifted and enhanced emissions is beneficial to promoting their applications. Luminescent materials based on aromatic heterocycles (e.g., pyrazine) usually have red-shifted and enhanced photoluminescence compared with phenyl-based luminescent materials. In this work, the photoluminescence behaviors of pyrazine and its derivatives (o-dichloro-, o-dicyano-, and dichlorodicyano-substituted) are compared with those of benzene and its derivatives. All compounds exhibit fluorescence emissions ranging from blue to yellow, and the fluorescence emissions of pyrazinyl compounds are more red-shifted than those of phenyl compounds. Except for the o-dicyano-substituted compound, pyrazinyl compounds exhibit stronger fluorescence emissions than corresponding phenyl compounds in both pure substances and ethanol solutions. In addition, both 5,6-dichloro-2,3-dicyanopyrazine (P4) and 4,5-dichloro-1,2-dicyanobenzene (B4) exhibit room temperature phosphorescence, and the maximum delayed emission wavelength is red-shifted from 575 nm of B4 to 637 nm of P4. The energy gaps between the highest occupied molecular orbital and the lowest unoccupied molecular orbital of the monomers of pyrazinyl compounds are reduced by 0.07-1.37 eV compared with the monomers of phenyl compounds, which is the fundamental reason for the red-shifted emissions of the pyrazinyl compounds. Moreover, compared to B4, the smaller molecular spacing in the P4 crystal structure facilitates interlayer electron transfer and hence the formation of more extended through-space conjugation, resulting in the red-shifted emission of P4. This work proves that pyrazine is a more efficient luminophore than benzene for constructing PL compounds with longer emission wavelengths and higher quantum yields, which are important in guiding the design and preparation of organic PL materials.

3.
Int J Mol Sci ; 24(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37047480

RESUMO

Very long-chain fatty acid (VLCFA) synthesis in plants, is primarily rate-limited by the enzyme 3-ketoacyl CoA synthase (KCS), which also controls the rate and carbon chain length of VLCFA synthesis. Disruption of VLCFA during pollen development, may affect the pollen wall formation and ultimately lead to male sterility. Our study identified 24 grapevine KCS (VvKCS) genes and provided new names based on their relative chromosome distribution. Based on sequence alignment and phylogenetic investigation, these genes were grouped into seven subgroups, members of the same subgroup having similar motif structures. Synteny analysis of VvKCS genes, showed that the segmental duplication events played an important role in expanding this gene family. Expression profiles obtained from the transcriptome data showed different expression patterns of VvKCS genes in different tissues. Comparison of transcriptome and RT-qPCR data of the male sterile grape 'Y-14' and its fertile parent 'Shine Muscat', revealed that 10 VvKCS genes were significantly differentially expressed at the meiosis stage, which is a critical period of pollen wall formation. Further, joint analysis by weighted gene co-expression network analysis (WGCNA) and Kyoto Encyclopedia of Genes and Genomes (KEGG), revealed that five of these VvKCS (VvKCS6/15/19/20/24) genes were involved in the fatty acid elongation pathway, which may ultimately affect the structural integrity of the pollen wall in 'Y-14'. This systematic analysis provided a foundation for further functional characterization of VvKCS genes, with the aim of grapevine precision breeding improvement.


Assuntos
Genes de Plantas , Infertilidade Masculina , Masculino , Humanos , Filogenia , Melhoramento Vegetal , Perfilação da Expressão Gênica , Transcriptoma , Infertilidade Masculina/genética , Ácidos Graxos/genética , Regulação da Expressão Gênica de Plantas
4.
Sensors (Basel) ; 22(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36560300

RESUMO

Because images are vulnerable to external attacks in the process of network transmission and traditional image encryption algorithms have limitations such as long encryption time, insufficient entropy or poor diffusion of cipher image information when encrypting color images, a fast image encryption algorithm based on logistics-sine-cosine mapping is proposed. The algorithm first generates five sets of encrypted sequences from the logistics-sine-cosine mapping, then uses the order of the encryption sequence to scramble the image pixels and designs a new pixel diffusion network to further improve the key sensitivity and plain-image sensitivity of the encryption algorithm. Finally, in a series of security analysis experiments, the experimental image Lena was tested 100 times, and the average encryption time was 0.479 s. The average value of the information entropy, pixel change rate and uniform average change intensity of the cipher image reached 7.9994, 99.62% and 33.48%, respectively. The experimental results show that the fast image encryption algorithm based on logistics-sine-cosine mapping takes less time to encrypt, and the cipher image has good information entropy and diffusivity. It is a safe and effective fast image encryption algorithm.

5.
Audiol Neurootol ; 26(6): 461-469, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34167116

RESUMO

OBJECTIVE: To analyze the factors affecting the long-term prognosis of tinnitus accompanied by unilateral idiopathic sudden sensorineural hearing loss (SSNHL). METHODS: A total of 161 patients with sudden hearing loss (HL) accompanied by tinnitus were enrolled. All patients had two separate telephone follow-ups and were asked about changes in tinnitus. The severity of tinnitus at admission and the outcome at discharge were assessed in terms of the patients' sex, age, level of HL, type of audiogram, etc. Results: The prognosis of tinnitus after SSNHL had no relationship with grades of HL or hearing recovery. Initial tinnitus level was remarkably associated with tinnitus improvement at discharge and was an independent risk factor for the long-term prognosis of residual tinnitus after SSNHL (odds ratio 0.722, 95% confidence interval 0.550-0.949, p = 0.019), and the median recovery time was 23.00 ± 3.80 months. CONCLUSIONS: Residual tinnitus after SSNHL has a tendency of self-recovery. The short-term prognosis of tinnitus may be related to psychological changes caused by hearing recovery, while the long-term prognosis of residual tinnitus after SSNHL is related only to the initial tinnitus level, with a median recovery time of approximately 2 years.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Zumbido , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Súbita/complicações , Humanos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Zumbido/complicações
6.
Environ Res ; 202: 111660, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34265353

RESUMO

A systematic understanding of the spatial distribution of water quality is critical for successful watershed management; however, the limited number of physical monitoring stations has restricted the evaluation of spatial water quality distribution and the identification of features impacting the water quality. To fill this gap, we developed a modeling process that employed the random forest regression (RFR) to model the water quality distribution for the Taihu Lake basin in Zhejiang Province, China, and adopted the Shapley Additive exPlanations (SHAP) method to interpret the underlying driving forces. We first used RFR to model three water quality parameters: permanganate index (CODMn), total phosphorus (TP), and total nitrogen (TN), based on 16 watershed features. We then applied the built models to generate water quality distribution maps for the basin, with the CODMn ranging from 1.39 to 6.40 mg/L, TP from 0.02 to 0.23 mg/L, and TN from 1.43 to 4.27 mg/L. These maps showed generally consistent patterns among the CODMn, TN, and TP with minor differences in the spatial distribution. The SHAP analysis showed that the TN was mainly affected by agricultural non-point sources, while the CODMn and TP were affected by agricultural and domestic sources. Due to differences in sewage collection and treatment between urban and rural areas, the water quality in highly populated urban areas was better than that in rural areas, which led to an unexpected positive relationship between water quality and population density. Overall, with the RFR models and SHAP interpretation, we obtained a continuous distribution pattern of the water quality and identified its driving forces in the basin. These findings provided important information to assist water quality restoration projects.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , China , Monitoramento Ambiental , Lagos , Nitrogênio/análise , Fósforo/análise , Rios , Poluentes Químicos da Água/análise
7.
Inorg Chem ; 59(17): 12625-12631, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32786726

RESUMO

A promising magnetic refrigerant, AlFe2B2, has been prepared for the first time by microwave (MW) melting of a mixture of constituent elements. For comparison, samples of AlFe2B2 have been also prepared by arc-melting, traditionally used for the synthesis of this material, and by induction (RF) melting, which was used in the very first report on the synthesis of AlFe2B2. Although an excess of Al has to be used to suppress the formation of ferromagnetic FeB, the other byproduct, Al13Fe4, is easily removed by acid treatment, affording phase-pure samples of AlFe2B2. Our analysis indicates that the equimolar Fe/B ratio typically used for the preparation of AlFe2B2 might not provide the best synthetic conditions, as it does not account for the full reaction stoichiometry. Furthermore, we find that the initial Al/Fe loading ratio strongly influences magnetic properties of the sample, as judged by the range of ferromagnetic ordering temperatures (TC = 280-293 K) observed in our experiments. The TC value increases with the decrease in the Al/Fe ratio, due to the change in the Al/Fe antisite disorder. The use of the same Al/Fe loading ratio in the arc-, RF-, and MW-melting experiments leads to samples with a more consistent TC of 286-287 K and similar values of the magnetocaloric effect.

8.
Sensors (Basel) ; 20(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991640

RESUMO

Deformation is a ubiquitous phenomenon in nature. This process usually refers to the change in shape, size, and position of an object in the time and spatial domain under various loads. Under normal circumstances, during engineering construction, technicians are generally required to monitor the safe operation of structural facilities in the transportation field and the health of bridge, because monitoring in the engineering process plays an important role in construction safety. Considering the reliability risk of sensors after a long-time work period, such as signal drift, accurate measurement of strain gauges is inseparable from the value traceability system of high-precision strain gauges. In this study, two vibrating wire strain gauges with the same working principle were measured using the parallel method at similar positions. First, based on the principle of time series, the experiment used high-frequency dynamic acquisition to measure the thermometer strain of two vibrating wire strain gauges. Second, this experiment analyzed the correlation between strain and temperature measured separately. Under the condition of different prestress, this experiment studied the influencing relationship of temperature corresponding variable. In this experiment, the measurement repetitiveness was analyzed using the meteorology knowledge of single sensor data, focused on researching the influence of temperature and prestress effect on sensors by analyzing differences of their measurement results in a specified situation. Then, the reliability and stability of dynamic vibrating wire strain gauge were verified in the experiment. The final conclusion of the experiment is the actual engineering in the later stage. Onsite online meteorology in the application provides support.

9.
J Environ Manage ; 268: 110707, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510441

RESUMO

Green roofs have been treated as practical low impact development (LID) strategies to retain stormwater runoff and alleviate the rainfall-induced flooding risks in urban regions. The purpose of this study was to analyze the hydrological effects of the spatial location of green roofs in urbanized catchments. In the built-up region of Beijing, 12 urbanized catchments with various architectural patterns were chosen as the study areas. To distinguish the spatial characteristics of roof surfaces, we defined the effective roof surfaces to distinguish from other types of roofs, which have more convenient or direct hydrological connections to drainage systems. A hydrological model was then used to simulate the stormwater mitigation performance of green roofs for the study catchments, which were assigned to different rainfall conditions. The simulation results confirmed the benefits of implementing green roofs for urban stormwater regulation. However, the spatial variability of green roofs showed inherent influences on the runoff mitigation capacity in urbanized catchments. Greening on effective roof surfaces would provide more effective stormwater regulation benefits, for reductions in both runoff volume and peak flow. In addition, the spatial arrangement characteristics of roof surfaces also influenced the hydrological efficiency of green roofs. The effect of the spatial location of green roofs on runoff mitigation was rainfall-dependent. These findings provide insights into the hydrological role of green roofs, and suggest that proper siting of LID facilities should be a consideration for urban stormwater management in order to fulfill the hydrological efficiency and cost-effectiveness planning target.


Assuntos
Chuva , Movimentos da Água , Pequim , Conservação dos Recursos Naturais , Hidrologia
10.
Microb Biotechnol ; 17(2): e14330, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38291799

RESUMO

The use of microbial inoculants in agriculture as biofertilisers and/or biopesticides is an appealing alternative to replace or reduce the practice of agrochemicals. Plant microbiota studies are revealing the different bacterial groups which are populating plant microbiomes re-energising the plant probiotic bacteria (PPB) translational research sector. Some single-microbial strain bioinoculants have proven valid in agriculture (e.g., based on Trichoderma, mycorrhiza or rhizobia); however, it is now recommended to consider multistrain consortia since plant-beneficial effects are often a result of community-level interactions in plant microbiomes. A limiting step is the selection of a fitting combination of microbial strains in order to accomplish the best beneficial effect upon plant inoculation. In this study, we have used a subset of 23 previously identified and characterised rice-beneficial bacterial colonisers to design and test a series of associated experiments aimed to identify potential PPB consortia which are able to co-colonise and induce plant growth promotion. Bacterial strains were co-inoculated in vitro and in planta using several different methods and their co-colonisation and co-persistence monitored. Results include the identification of two 5-strain and one 2-strain consortia which displayed plant growth-promoting features. Future practical applications of microbiome research must include experiments aimed at identifying consortia of bacteria which can be most effective as crop amendments.


Assuntos
Inoculantes Agrícolas , Microbiota , Raízes de Plantas/microbiologia , Bactérias/genética , Plantas
11.
Environ Sci Pollut Res Int ; 31(28): 41167-41181, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38847954

RESUMO

Lake surface water temperature (LSWT) plays a crucial role in assessing the health of aquatic ecosystems. Variations in LSWT can significantly impact the physical, chemical, and biological processes within lakes. This study investigates the long-term changes in surface water temperature of the Dongting Lake, China. The LSWT is retrieved using Landsat thermal infrared imageries from 1988 to 2022 and validated with in situ observations, and the change characteristics of LSWT and near-surface air temperature (NSAT) as well as the spatial distribution characteristics of LSWT are analyzed. Additionally, the contribution rates of different meteorological factors to LSWT are quantified. The results show that the accuracy assessment of satellite-derived temperatures indicates a Nash-Sutcliffe efficiency coefficient (NSE) of 0.961, suggesting an accurate retrieval of water temperature. From 1988 to 2022, both the annual average LSWT and NSAT of Dongting Lake exhibit an increasing trend, with similar rates of warming. They both undergo a mutation in 1997 and have the main periods on the 11-year and 4-year time scales. The changes in NSAT emerge as one of the important factors contributing to variations in LSWT. Among the multiple meteorological factors, NSAT exhibits a significant correlation with LSWT (R = 0.822, α < 0.01). Furthermore, NSAT accounts for the highest contribution rate to LSWT, amounting to 67.5%. The distribution of LSWT within Dongting Lake exhibits spatial variations, with higher LSWT observed on the west part compared to the east part during summer, while lower LSWT occurs on the west part during winter. The findings of this study can provide a scientific understanding for the long-term thermal regimes of lakes and help advance sustainable lake management.


Assuntos
Monitoramento Ambiental , Lagos , Imagens de Satélites , Temperatura , China
12.
Acta Otolaryngol ; 144(3): 168-174, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38753897

RESUMO

BACKGROUND: The pathway by which drugs are injected subcutaneously behind the ear to act on the inner ear has not been fully elucidated. OBJECTIVES: To compare the uptake of gadopentetate dimeglumine (Gd-DTPA) and dexamethasone (Dex) in the cochlea and facial nerve of rats following different administrations. MATERIALS AND METHODS: Magnetic resonance imaging was applied to observe the distribution of Gd-DTPA in the facial nerve and inner ear. We observed the uptake of Dex after it was injected with different methods. RESULTS: Images of the intravenous (IV) and intramuscular (IM) groups showed that the bilateral cochlea of the rat was visualized almost simultaneously. While in the left post-auricular (PA) injection group, it was asynchronous. The maximum accumulation (Cmax) of the Gd in the left facial nerve of the PA group (35.406 ± 5.32) was substantially higher than that of the IV group (16.765 ± 3.7542) (p < .01). CONCLUSIONS: Compared with systemic administration, PA has the advantages of long Gd and Dex action time and high accumulation concentration to treat facial nerve diseases. SIGNIFICANCE: The distribution of Gd and Dex in the inner ear and facial nerve of rats following PA injection might be unique.


Assuntos
Meios de Contraste , Dexametasona , Nervo Facial , Gadolínio DTPA , Imageamento por Ressonância Magnética , Animais , Dexametasona/farmacocinética , Dexametasona/administração & dosagem , Gadolínio DTPA/farmacocinética , Gadolínio DTPA/administração & dosagem , Meios de Contraste/farmacocinética , Meios de Contraste/administração & dosagem , Nervo Facial/metabolismo , Nervo Facial/efeitos dos fármacos , Ratos , Masculino , Ratos Sprague-Dawley , Orelha Interna/metabolismo , Orelha Interna/efeitos dos fármacos , Orelha Interna/diagnóstico por imagem , Injeções Intramusculares
13.
J Ethnopharmacol ; 333: 118457, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38866117

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lian Qiao (LQ), the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a well-documented traditional Chinese medicine known for its detoxifying and heat-clearing properties. Clinically, compounds containing LQ are widely used to treat thrombotic diseases, indicating that it may have antithrombotic effects. However, its exact mechanism of action remains unknown. AIM OF THE STUDY: This study aimed to verify the antithrombotic effect of LQ and further explore the material basis and target mechanism of its antithrombotic effect using various biological methods. MATERIALS AND METHODS: An epinephrine-collagen-thrombin-induced mouse model of acute pulmonary embolism (APE) was established to study the effects of LQ on thrombus development. A UPLC/Q/TOF-MS screening and identification system based on the inhibition of platelet aggregation and Ca2+ antagonism was established to determine the pharmacodynamic components of LQ that inhibit platelet activation. The inhibitory effect of active ingredients on platelet activation, and the determination of the target of their inhibitory effect on platelet activation have been studied using chemical proteomics. Furthermore, based on the structure and function of the target protein, a multidisciplinary approach was adopted to analyze the molecular mechanism of active ingredient binding to target proteins and to evaluate the effects of active ingredients on the downstream signaling pathways of target proteins. RESULTS: LQ showed significant anticoagulant effects in APE model mice. Phillyrin and phillygenin were the antiplatelet-activating components of LQ. PLCß3 was identified as a target for inhibiting platelet activation by phillyrin and its metabolites. The mechanism underlying the effect involves phillyrin and its metabolites inhibiting PLCß3 activity by blocking the binding of PLCß3 to Gαq through non-covalently targeting the ASN260 of PLCß3, thus inhibiting the downstream Gαq-PLCß3-Ca2+ signaling pathway, effectively hindering platelet activation and therefore playing an anticoagulant role. CONCLUSION: This study not only proposes and validates the antithrombotic effect of LQ for the first time but also finds that phillyrin and phillygenin are the main pharmacological substances through which LQ exerts antithrombotic activity and reveals a novel mechanism by which they exert antiplatelet activity by directly targeting and inhibiting PLCß3 activity. These findings significantly contribute to our understanding of the therapeutic potential of phillyrin and provide important clues for the discovery and development of new antiplatelet drugs.

14.
Sci Total Environ ; 897: 166388, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37597546

RESUMO

Soil moisture (SM) has changed significantly over the past 40 years in China, while NDVI has varied dramatically, leading to increasing regional conflict between vegetation growth and water resource use. Quantifying the bidirectional dependency between SM and NDVI is essential for understanding the balance between land vegetation and water resources. However, few studies have reported their mutual feedback and spatiotemporal bidirectional dependency. This paper aims to reveal the bidirectional dependency between SM and NDVI using Granger causality test to show spatiotemporal tendency coupling patterns through trend coupling analysis, wavelet transform, and lag correlation. The Results indicated that a coupling relationship existed between SM and NDVI over most of China. The unidirectional Granger effect between SM on NDVI was 58 %, the unidirectional Granger effect of NDVI on SM was 26 %, and the bidirectional Granger relationship between SM and NDVI was 16 %. The Granger relationship is different for different soil layers or land cover types. SM and NDVI increased together in 36 % of the land cover areas, but SM increased and NDVI decreased in 12 %, and the SM decreased and NDVI increased in 27 %. The trend coupling between SM and NDVI has spatial heterogeneity. There is no change rule of coupling relationship with drought variation, but SM and NDVI increased together with more overlapping ecological restoration projects. SM decreased with the increase of NDVI from 1982 to 2010 but has reversed since 2011. NDVI and SM co-increased significantly with the implementation of ecological restoration projects during 2011-2022. The coupling relationship has a time lag effect of 1-3 months, and the time lag of NDVI to SM of deep soil layers mainly occurred in Southern China. This study illustrated the coupling framework and feedback analysis between SM and vegetation greening, which is helpful for the scientific implementing ecological restoration projects and the management of ecosystem carbon and water cycles.


Assuntos
Ecossistema , Solo , China , Mudança Climática
15.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862517

RESUMO

For precise measurement of the moment of inertia (MOI) of asymmetric objects, using an air bearing torsional pendulum, the nonlinearity of the torsion bar and the damping effect caused by the interaction between air and sample need to be included in the analysis. The instantaneous undamped natural frequency and instantaneous damping coefficient of the motion are obtained from the Hilbert transform of the angular displacement signal and are used for data fitting to calculate the MOI. Measurements for algorithm verification were made using a special sample with large windvanes to increase the damping effect. The nonlinear analysis of the MOI experimental results indicated a relative error of less than 0.1% compared with 0.3% for classical linear analysis of the data.

16.
Environ Sci Pollut Res Int ; 29(20): 29689-29703, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34993793

RESUMO

The development of urban agglomeration further deteriorates the air pollution status arising from urbanization. However, disparities in the urbanization process across different urban agglomerations may shape unique regional air pollution characters, and further complicate its driving mechanism. In this study, 11 urban agglomerations with different urbanization levels in China thus were chosen as the case study areas, to explore the spatiotemporal heterogeneity of PM2.5 and its potential driving difference related to the urbanization process from a multi-urban agglomeration perspective. The ground-monitored PM2.5 data and socioeconomic panel data (2015-2018) were processed using multiple statistical analysis methods, and the main findings of this study can be generated as followed: (1) significant spatial heterogeneity characteristics of PM2.5 pollution were recognized across the study area. And even though obvious improvement in the air quality during the study period, PM2.5 concentration remains at a high level for most of the urban agglomerations. (2) Urbanization process has a substantial contribution to regional PM2.5 pollution, and significant differences of the urbanization factors on PM2.5 concentration across the urban agglomerations assigned with various urbanization levels were emphasized. The significance of this study is to provide insight into the relationship of the urbanization process on PM2.5 pollution in different urban agglomerations and to offer a scientific basis for regional cooperation for air pollution regulation among multiple urban agglomerations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Urbanização
17.
Curr Res Food Sci ; 5: 1740-1749, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36268134

RESUMO

The survival mechanism of Salmonella treated with high-intensity ultrasound (HIU) should be explored to further enhance the bactericidal efficacy of HIU. In this study, culturable Salmonella was reduced by applying HIU. Electron microscope imaging revealed that HIU caused the disintegration of cell structure and leakage of intracellular substances. For the Salmonella after the HIU treatment, key enzymes of the tricarboxylic acid [TCA] cycle were significantly downregulated, which led to a reduced ATP content (45.25%-75.00%), although ATPase activity was augmented by 33.82%-60.64% in the Salmonella. Accordingly, surviving Salmonella could have tolerated the stress of HIU by upregulating their environmental sensing (two-component system), chemotaxis (bacterial chemotaxis), substance uptake (ABC transporter), and ATP production (oxidative phosphorylation). Therefore, synergistically blocking the ATP production, signal transduction, or substance intake of Salmonella offer promising potential strategies to improve the bactericidal effect of HIU in industrial food processing.

18.
Microbiol Spectr ; 10(4): e0057022, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35862944

RESUMO

Sugarcane smut caused by the basidiomycetous fungus Sporisorium scitamineum leads to severe economic losses globally. Sexual mating/filamentation of S. scitamineum is critical for its pathogenicity, as only the dikaryotic hyphae formed after sexual mating are capable of invading the host cane. Our comparative transcriptome analysis showed that the mitogen-activated protein kinase (MAPK) pathway and the AGC kinase Agc1 (orthologous to yeast Rim15), both governing S. scitamineum mating/filamentation, were induced by elevated tryptophol level, supporting a positive regulation of S. scitamineum mating/filamentation by tryptophol. However, the biosynthesis pathway of tryptophol remains unknown in S. scitamineum. Here, we identified an aminotransferase orthologous to the established tryptophan aminotransferase Tam1/Aro8, catalyzing the first step of tryptophan-dependent indole-3-acetic acid (IAA) production as well as that of the Ehrlich pathway for tryptophol production. We designated this S. scitamineum aminotransferase as SsAro8 and found that it was essential for mating/filamentation. Comparative metabolomics analysis revealed that SsAro8 was involved in tryptophan metabolism, likely for producing important intermediate products, including tryptophol. Exogenous addition of tryptophan or tryptophol could differentially restore mating/filamentation in the ssaro8Δ mutant, indicating that in addition to tryptophol, other product(s) of tryptophan catabolism may also be involved in S. scitamineum mating/filamentation regulation. S. scitamineum could also produce IAA, partially dependent on SsAro8 function. Surprisingly, photodestruction of IAA produced the compound(s) able to suppress S. scitamineum growth/differentiation. Lastly, we found that SsAro8 was required for proper biofilm formation, oxidative stress tolerance, and full pathogenicity in S. scitamineum. Overall, our study establishes the aminotransferase SsAro8 as an essential regulator of S. scitamineum pathogenic differentiation, as well as fungus-host interaction, and therefore of great potential as a molecular target for sugarcane smut disease control. IMPORTANCE Sugarcane smut caused by the basidiomycete fungus S. scitamineum leads to massive economic losses in sugarcane plantation globally. Dikaryotic hyphae formation (filamentous growth) and biofilm formation are two important aspects in S. scitamineum pathogenesis, yet the molecular regulation of these two processes was not as extensively investigated as that in the model pathogenic fungi, e.g., Candida albicans, Ustilago maydis, or Cryptococcus neoformans. In this study, a tryptophan aminotransferase ortholog was identified in S. scitamineum, designated SsAro8. Functional characterization showed that SsAro8 positively regulates both filamentous growth and biofilm formation, respectively, via tryptophol-dependent and -independent manners. Furthermore, SsAro8 is required for full pathogenicity and, thus, is a promising molecular target for designing anti-smut strategy.


Assuntos
Basidiomycota , Saccharum , Ustilaginales , Doenças das Plantas/microbiologia , Saccharum/metabolismo , Saccharum/microbiologia , Transaminases/metabolismo , Triptofano/metabolismo , Triptofano Transaminase/metabolismo , Ustilaginales/fisiologia
19.
J Vestib Res ; 32(1): 57-67, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34180440

RESUMO

BACKGROUND: Migraine is more common in Meniere's disease patients, who have some certain anatomical variations. But there are limited studies focusing on the anatomical variations in patients with Meniere's disease and migraine. OBJECTIVE: To explore the clinical and anatomical features in Meniere's disease patients with and without migraine, determining whether the coexistence of migraine can be used as a basis for clinical subtyping of Meniere's disease. METHODS: Ninety-five Meniere's disease patients and ninety-five healthy subjects matched with age, sex were selected. A detailed questionnaire based on the diagnosis criteria of Meniere's disease and migraine was designed. According to the CT scan, we divided the mastoid cell system of all the subjects into two types: well-pneumatization type and poor-pneumatization type. Meanwhile, the shortest distance between the sigmoid sinus and the posterior wall of the external acoustic canal was measured. RESULTS: Compared with those without migraine, Meniere's disease patients with migraine had a higher female comorbidity, poorer mastoid pneumatization, shorter distance between the sigmoid sinus and posterior wall of the external acoustic canal, longer history, higher frequency of vertigo attacks and better average hearing threshold. CONCLUSIONS: In our study, anatomical features as well as several clinical manifestations were proved to differ significantly between Meniere's disease patients with and without migraine, indicating the coexistence of migraine may be one standard for the clinical subtyping of Meniere's disease.


Assuntos
Doença de Meniere , Transtornos de Enxaqueca , Feminino , Humanos , Doença de Meniere/complicações , Doença de Meniere/diagnóstico por imagem , Transtornos de Enxaqueca/diagnóstico por imagem , Vertigem/diagnóstico
20.
Front Neurol ; 12: 798569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970216

RESUMO

The frequency of intratympanic (IT) steroid injection varies from once daily to once weekly or less among studies and does not reach a uniform standard. This study investigated the potential association between the number of IT steroid injections and hearing recovery to determine the optimal number in sudden sensorineural hearing loss (SSNHL) patients. A retrospective study involving 233 SSNHL patients receiving IT steroids plus batroxobin within 7 days of onset was performed. Patients were followed up for 3 months. More than 15 dB of HL improvement in the pretreatment pure tone average (PTA) was defined as effective. The effective group had a higher IT injection numbers than the ineffective group (≥ 6 times: 84.6 vs. 61.1, p < 0.001). Regardless of the unadjusted model or adjusted model, patients who received more frequent IT steroid injections seemed more likely to recover hearing (unadjusted model, OR, 95% CI: 1.25, 1.06-1.48; p = 0.007; adjusted model, OR, 95% CI: 1.21, 1.01-1.45; p = 0.044). Six IT injections had the highest rate of hearing recovery (79.1%). In conclusion, IT injection number was an independent factor that was positively associated with hearing recovery, and the optimal number of IT steroid injections was 6. Batroxobin plus higher number of IT steroid injections showed more effective for treating SSNHL.

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