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1.
J Hazard Mater ; 480: 135870, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39298961

RESUMEN

Environmental persistent free radicals (EPFRs) derived from chlorophenols, triggered by light or heat exposure, pose significant ecological concerns, yet the impact of chlorine substituents on EPFRs formation and reactivity remains inadequately understood. Through an intentional synthesis of chlorophenol-derived EPFRs with varying chlorine contents and positioning, we elucidated the role of chlorine in the photoactivation of molecular oxygen. Our combined experimental and theoretical analysis reveals that these EPFRs are primarily oxygen-centered phenoxy radicals, establishing a direct link between chlorine substitution patterns and their ability to activate molecular oxygen under visible light. Increased chlorine content enhances EPFRs formation by elevating the positive charge on the phenolic hydroxyl group's hydrogen atom, facilitating its removal. Moreover, the capability of EPFRs to activate molecular oxygen was directly correlated with chlorine content, with 2,3,5,6-tetrachlorophenol-derived EPFRs showcasing the highest activity. This activity is attributed to their structural propensity for TCSQ·- species generation. Furthermore, our study established a significant correlation between the toxicity and activity of EPFRs, emphasizing the critical role of halogen substituents in determining the reactivity of EPFRs. These insights contribute to our understanding of their environmental and toxicological ramifications, underscoring the imperative for continued research aimed at mitigating their detrimental impacts.

2.
Molecules ; 28(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687200

RESUMEN

The isolation and identification of an increasing number of secondary metabolites featuring unique skeletons and possessing diverse bioactivities sourced from marine microorganisms have garnered the interest of numerous natural product chemists. There has been a growing emphasis on how to cultivate microorganisms to enhance the chemical diversity of metabolites and avoid the rediscovery of known ones. Given the significance of secondary metabolites as a means of communication among microorganisms, microbial co-culture has been introduced. By mimicking the growth patterns of microbial communities in their natural habitats, the co-culture strategy is anticipated to stimulate biosynthetic gene clusters that remain dormant under traditional laboratory culture conditions, thereby inducing the production of novel secondary metabolites. Different from previous reviews mainly focusing on fermentation conditions or metabolite diversities from marine-derived co-paired strains, this review covers the marine-derived co-culture microorganisms from 2012 to 2022, and turns to a particular discussion highlighting the selection of co-paired strains for marine-derived microorganisms, especially the fermentation methods for their co-cultural apparatus, and the screening approaches for the convenient and rapid detection of novel metabolites, as these are important in the co-culture. Finally, the structural and bioactivity diversities of molecules are also discussed. The challenges and prospects of co-culture are discussed on behave of the views of the authors.


Asunto(s)
Productos Biológicos , Microbiota , Técnicas de Cocultivo , Acuicultura , Fermentación
3.
Ecol Evol ; 13(8): e10368, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37546567

RESUMEN

The temporal stability of grassland plant communities is substantially affected by soil nutrient enrichment. However, the potential main and interactive effects of arbuscular mycorrhizal fungi (AMF) and soil nitrogen (N) and phosphorus (P) enrichment on the stability of plant productivity have not yet been clarified. We combined a three-year in situ field experiment to assess the impacts of soil fertilization and AMF on the stability of plant productivity. P addition decreased the stability of plant productivity by increasing the standard deviation relative to the mean of plant productivity. However, compared to species richness, the stability of C3 grasses and other functional groups asynchrony were the most important drivers changing the stability of plant productivity. The negative impacts of P addition overrode the impacts of AMF on the stability of plant productivity. Overall, our study suggests the importance of soil nutrient availability over AMF in terms of shaping the stability of plant productivity. Our results also suggest that three-year anthropogenic soil nutrient enrichment could reduce the stability of plant communities in grassland regardless of AMF in the P-limited grassland ecosystem.

4.
Front Psychol ; 13: 1082889, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36582323

RESUMEN

Reduced audit quality behavior is widespread in the auditor's practice and is an important factor threatening audit quality. Some prior studies have investigated the relationship between auditors' psychological contract violation and reduced audit quality behavior. However, the research of relationship between emotional intelligence (EI) and auditors' behavior is still in its infancy despite the fact that the auditing profession would benefit greatly from improving audit team's EI. This study examines whether and why the audit team's EI restrains the audit quality reduction behavior in audit firms. In the study, our hypotheses are tested using a data set collected from 326 respondents in Chinese audit firms. The results are as follows: firstly, audit team's EI is directly negatively related to reduced audit quality behavior. Secondly, EI is indirectly related to reduced audit quality behavior, through team trust. The results of structural equation modeling (SEM) indicate a mediation model where team trust is negatively related to reduced audit quality behavior. Thirdly, knowledge sharing is a significant mechanism that moderates the effects of different types of EI on audit quality reduction behavior. In the audit team with high knowledge sharing, the audit team's EI can refrain the audit quality reduction behavior; In the audit team with low knowledge sharing, the audit team's EI has no significant effect on audit quality reduction behavior. This study expands the factors affecting audit quality to the psychological level of audit teams, enriches the literature on audit team's behavior characteristics, and provides direct evidence for the relationship between audit team's psychological characteristics and audit quality.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36141465

RESUMEN

The contradiction between the endless pursuit of material possessions and finite natural resources hampers ecological well-being performance (EWP) improvement. Green transformation, recognized as an emerging strategy in sustainable development, can help to coordinate ecological, social, and economic growth by optimizing resource usage, with the ultimate objective of enhancing EWP. This research quantifies how green transformation influences EWP by using panel data from 78 prefecture-level cities in western China from 2012 to 2019. Using the super-SBM and entropy weight models, we assess the EWP and green transformation index (GTI) of 78 prefecture-level cities in western China. On this basis, we quantify the spatial characteristics of EWP by an analysis of the Theil index and spatial autocorrelation. Finally, we examine how GTI affects EWP using the Spatial Durbin model. The results demonstrate that the GTI can raise the EWP of local and nearby cities in western China. According to a GTI analysis of internal indicators, the industrial solid waste usage, harm-less treatment rate of domestic waste, savings level, and R&D expenditure significantly affect EWP. In contrast, the soot emission and consumption levels impede EWP advancement. The analysis of effect decomposition indicates that the sewage treatment rate, expenditure on science and technology, and green patents have a significant spatial spillover effect on the improvement of EWP.


Asunto(s)
Conservación de los Recursos Naturales , Residuos Sólidos , China , Ciudades , Desarrollo Económico , Eficiencia , Aguas del Alcantarillado , Hollín
6.
BMJ Open ; 11(5): e046003, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-34006551

RESUMEN

INTRODUCTION: Acute ischaemic stroke (AIS) is not only seriously damaging to the physical and mental health of patients, but also has become a major social public health problem. Effective dyskinesia rehabilitation treatment in convalescence is of great significance for AIS patients' prognosis and quality of life. Tai Chi (TC) shows great potential in improving motor function. This trial aims to evaluate the clinical efficacy of modified TC postural training (TPT), and to explore the related central-peripheral neurotransmitter mechanisms. METHODS/DESIGN: The proposed study will be a multicentre randomised controlled trial. The trial will randomise 120 eligible AIS patients in a 1:1 ratio to receive TPT or Bobath rehabilitation training. Each training session will last 40 min and will be implemented once a day and five times per week (from Monday to Friday) in a duration of 4 weeks. After finishing the 4-week treatment, another 3-month follow-up period will be seen. Root mean square generated from the surface electromyogram (sEMG) will be the primary outcome. Other sEMG time-domain parameters and frequency-domain parameters and clinical scales assessment will be the secondary outcomes. Peripheral blood samples will be collected at baseline and at the end of 4-week treatment, which will be used to explore the related therapeutic mechanisms. Intention-to-treat analysis and per-protocol analysis will both be implemented in this trial. ETHICS AND DISSEMINATION: The study has been approved by Ethics Committee of Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, being granted approval numbers DZMEC-KY-2020-22. The research results will be disseminated through (open access) peer-reviewed publications and presentations at conferences. TRIAL REGISTRATION NUMBER: ChiCTR2000032999.


Asunto(s)
Isquemia Encefálica , Discinesias , Accidente Cerebrovascular Isquémico , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Taichi Chuan , Humanos , Estudios Multicéntricos como Asunto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
J Xray Sci Technol ; 28(4): 783-798, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32417830

RESUMEN

OBJECTIVE: To evaluate skeletal and dental changes in patients with skeletal Class III malocclusion and facial asymmetry after surgical-orthodontic treatment using cone-beam computerized tomography (CBCT). METHODS: This study included forty adult patients diagnosed with skeletal Class III malocclusion and asymmetry who underwent either isolated mandibular surgery or bimaxillary surgery. CBCT scans were taken before treatment (T0), at the completion of presurgical orthodontic treatment (T1) and after treatment (T2). Mimics 17.0 and 3-Matics 7.0 were used to measure skeletal and dental parameters. Skeletal and dental changes within each group from pretreatment to posttreatment were assessed, and Pearson correlation analysis was used to analyze the correlations among skeletal changes. RESULTS: The three-dimensional changes in condylar position were insignificant after surgical-orthodontic treatment in either group (P > 0.05). However, in the one-jaw surgery group, there were significant backward rotations of the condyle and ramus on the nondeviated side (P < 0.05), and the condyle on the deviated side rotated inward and forward significantly in the two-jaw surgery group (P < 0.05) at T2. There were no significant differences in the changes in the total alveolar bone thickness of bilateral first molars during dental decompensation (P > 0.05). The ratio between the buccal and the total bone thickness around the maxillary first molar on the deviated side decreased significantly at T1, as did those around the mandibular first molar on the nondeviated side (P < 0.05). CONCLUSIONS: Condylar angulations were less stable after treatment (7 to 9 months after surgery) in both the one-jaw and the two-jaw surgery groups, while condylar displacements were insignificant. In addition, orthodontists should keep a watchful eye to the relative position of the root in the alveolar bone during tooth decompensation.


Asunto(s)
Asimetría Facial/diagnóstico por imagen , Imagenología Tridimensional , Maloclusión de Angle Clase III/diagnóstico por imagen , Adulto , Tomografía Computarizada de Haz Cónico , Asimetría Facial/patología , Asimetría Facial/cirugía , Femenino , Humanos , Masculino , Maloclusión de Angle Clase III/patología , Maloclusión de Angle Clase III/cirugía , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Procedimientos Quirúrgicos Orales , Ortodoncia , Diente/diagnóstico por imagen , Diente/cirugía , Resultado del Tratamiento , Adulto Joven
8.
Int J Pediatr Otorhinolaryngol ; 105: 138-145, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29447802

RESUMEN

OBJECTIVES: The purpose of this study was to assess, through a systematic review and meta-analysis, the efficacy of maxillary protraction appliances (MPAs) on improving pharyngeal airway dimensions in growing class III patients with maxillary retrognathism. METHODS: An electronic search in PubMed, Cochrane Library, Web of Science, and EMBASE was until September 2nd, 2017. The assessments of methodological quality of the selected articles were performed using the Newcastle-Ottawa Scale. Review Manager 5.3 (provided by the Cochrane Collaboration) was used to synthesize the effects of MPAs on pharyngeal airway dimensions. RESULTS: Following full-text articles evaluation for eligibility, 6 studies (168 treated subjects and 140 untreated controls) were included in final quantitative synthesis and they were all high-quality. Compared to untreated control groups, the treatment groups had increased significantly nasopharyngeal airway dimensions with the following measurements: PNS-AD1 (fixed: mean difference, 1.33 mm, 95% CI, 0.48mm-2.19 mm, P = .002), PNS-AD2 (random: mean difference, 1.91 mm, 95% CI, 0.02mm-3.81 mm, P = .05), aerial nasopharyngeal area (fixed: mean difference, 121.91 mm2, 95% CI, 88.70 mm2-155.11 mm2, P < .00001) and total nasopharyngeal area (fixed: mean difference, 142.73 mm2, 95% CI, 107.90 mm2-177.56 mm2, P < .00001). Meanwhile, McNamara's upper pharynx dimension (fixed: mean difference, 0.96 mm, 95% CI, 0.29mm-1.63 mm, P = .005), which was highly related to post-palatal airway dimension, was also improved significantly. However, no statistically significant differences in adenoidal nasopharyngeal area (P > .05) and McNamara's lower pharynx dimension (P > .05) existed. CONCLUSIONS: MPAs can increase post-palatal and nasopharyngeal airway dimensions in growing skeletal class III subjects with maxillary retrusion. It may be suggested that MPAs have the potential to reduce the risk of obstructive sleep apnea syndrome in children with maxillary retrusion by enlarging airway space.


Asunto(s)
Maloclusión de Angle Clase III/terapia , Retrognatismo/terapia , Apnea Obstructiva del Sueño/etiología , Cefalometría/métodos , Niño , Femenino , Humanos , Masculino , Maloclusión de Angle Clase III/complicaciones , Maxilar/anomalías , Faringe/fisiopatología , Retrognatismo/complicaciones , Apnea Obstructiva del Sueño/terapia
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