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1.
Angew Chem Int Ed Engl ; : e202402241, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567831

RESUMEN

Herein we present a new strategy for the oxidative synthesis of formamides from various types of amines and bioderived formyl sources (DHA, GLA and GLCA) and molecular oxygen (O2) as oxidant on g-C3N4 supported Cu catalysts. Combined characterization data from EPR, XAFS, XRD and XPS revealed the formation of single CuN4 sites on supported Cu(phen)2/C3N4 catalyst. EPR spin trapping experiments disclosed ●OOH radicals as reactive oxygen species and ●NR1R2 radicals being responsible for the initial C-C bond cleavage. Control experiments and DFT calculations showed that the successive C-C bond cleavage in DHA proceeds via a reaction mechanism co-mediated by ●NR1R2 and ●OOH radicals based on the well-equilibrated CuII and CuI cycle. Our system has much higher activity (TOF) than those using noble metals.

2.
BMC Public Health ; 24(1): 953, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570765

RESUMEN

OBJECTIVE: The diagnosis of hidden hearing loss (HHL) in calm state has not yet been determined, while the nutritional status is not involved in its pathogenic risk factors. In utero iron deficiency (ID) may delay auditory neural maturation in infants. We evaluated the association between ID and HHL as well as the modification effect of socioeconomic status (SES) on this association in newborns. STUDY DESIGN: We included 859 mother-newborns from the baseline of this observational northeast cohort. Data on exposure assessment included iron status [maternal hemoglobin (Hb) and neonatal heel prick serum ferritin (SF)] and SES (occupation, education and income). Auditory neural maturation was reflected by auditory brainstem response (ABR) testing and electrocochleography (ECochG). RESULTS: Iron status and SES were independently and jointly associated with the prediction of neonatal HHL by logistic and linear regression model. The mediation effects were performed by Process. ID increased absolute latency wave V, interpeak latency (IPL) III-V, and summting potentials (SP) /action potentials (AP), which were combined as HHL. Low SES showed the highest risk of HHL and the highest levels of related parameters in ID newborns. Moreover, after Corona Virus Disease 2019 (COVID-19) were positive, preschool children who experience ID in neonatal period were more likely to suffer from otitis media with effusion (OME). High SES also showed similar risk effects. CONCLUSION: Both low and high SES may strengthen the risk of ID on neonatal HHL in Northeast China.


Asunto(s)
Deficiencias de Hierro , Madres , Lactante , Femenino , Preescolar , Humanos , Recién Nacido , 60707 , Hierro , Clase Social
3.
Psychiatry Res Neuroimaging ; 336: 111749, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37977097

RESUMEN

BACKGROUND: Dysfunctions of the striatum have been repeatedly observed in autism spectrum disorder (ASD). However, previous studies have explored the static functional connectivity (sFC) of the striatum in a single frequency band, ignoring the dynamics and frequency specificity of brain FC. Therefore, we investigated the dynamic FC (dFC) and sFC of the striatum in the slow-4 (0.027-0.073 Hz) and slow-5 (0.01-0.027 Hz) frequency bands. METHODS: Data of 47 ASD patients and 47 typically developing (TD) controls were obtained from the Autism Brain Imaging Data Exchange (ABIDE) database. A seed-based approach was used to compute the dFC and sFC. Then, a two-sample t-test was performed. For regions showing abnormal sFC and dFC, we performed clinical correlation analysis and constructed support vector machine (SVM) models. RESULTS: The middle frontal gyrus (MFG), precuneus, and medial superior frontal gyrus (mPFC) showed both dynamic and static alterations. The reduced striatal dFC in the right MFG was associated with autism symptoms. The dynamic‒static FC model had a great performance in ASD classification, with 95.83 % accuracy. CONCLUSIONS: The striatal dFC and sFC were altered in ASD, which were frequency specific. Examining brain activity using dynamic and static FC provides a comprehensive view of brain activity.


Asunto(s)
Trastorno del Espectro Autista , Mapeo Encefálico , Humanos , Mapeo Encefálico/métodos , Trastorno del Espectro Autista/diagnóstico por imagen , Vías Nerviosas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen
4.
ACS Appl Mater Interfaces ; 14(45): 51476-51486, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36341506

RESUMEN

Severe competition between nanolubricant additives and polar lubricating oil molecules for the formation of lubricant films has been hindering the progress of green and advanced lubricants. In this work, based on the tautomerism of cyanuric acid molecule (trione and triol configurations), two kinds of triazine-based covalent-organic frameworks (COFs), that is, Ton-COFs and Tol-COFs, were synthesized as additives of the polar PEG 400 oil, realizing compromise between them by providing delicate interactions. The triazine matrix bonding with intense polar groups in the framework of additives offers more powerful interactions to competitively form the adsorbed lubricant film on the surface of the metal substrate over PEG 400 oil and also bolts PEG 400 oil molecules by the hydrogen bonding inside the pore of the framework to cooperatively bear against the load. Molecular quantum chemical calculations further confirm that Ton-COFs can produce a more intense interaction with Fe atoms in the form of coordination and ions···π than Tol-COFs, far beyond PEG 400, and the cross-sectional profile of the worn surface definitely exhibits a protective lubricant film only composed of Ton-COFs. Consequently, at the low concentration of 0.3 wt %, the excellent friction reduction (41.2%) and antiwear property (97.4%) are achieved for the Ton-COFs compared to pure PEG 400 oil; moreover, 28.6% and 79.0% for Tol-COFs at the essential concentration of 0.7 wt % are achieved. This finding provides a novel insight from molecules to materials into guiding the development of additives for advanced lubricants.

5.
Nonlinear Dyn ; 110(3): 2931-2947, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36035015

RESUMEN

Supply chain viability concerns the entire supply system rather than one company or one single chain to survive COVID-19 disruptions. Mobility restriction and overall demand decline lead to systematically cascading disruptions that are more severe and longer lasting than those caused by natural disasters and political conflicts. In the present study, the authors find that large companies and manufacturers with traditional advantages suffer greater losses than small ones, which is conceptualized as the "Hub Paradox" by empirically investigating one Warp Knitting Industrial Zone of China. An underload cascading failure model is employed to simulate supply chain viability under disruptions. Numerical simulations demonstrate that when the load decreases beyond a threshold, the viability will drop down critically. Besides, supply chain viability depends on two aspects: the adaptive capability of the manufacturers themselves and the adaptive capability of the connections of the supply network. The comparison study demonstrates that enhancing cooperative relations between hub and non-hub manufacturers will facilitate the entire supply network viability. The present study sheds light on viable supply chain management. Compared with conventionally linear or resilient supply chains, intertwined supply networks can leverage viability with higher adaptation of redistributing production capacities among manufacturers to re-establish overall scale advantages. Finally, the present study also suggests solving the "Hub Paradox" from the perspective of complex adaptive system. Supplementary Information: The online version contains supplementary material available at 10.1007/s11071-022-07741-8.

6.
Environ Monit Assess ; 194(2): 124, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35076795

RESUMEN

In 2013, the government of Zhejiang Province put forward a strategic project named "Five Water Cohabitation" (FWC) by integrating five water treatments: "sewage treatment," "flood prevention," "drainage system improvement," "water supply guarantee," and "water saving promotion." It has been eight years since the project was proposed and launched. The primary purpose of the present study is to investigate the performance and significant effects of the project on the sustainable development of agriculture. This study investigates the project's implementation from four aspects: environmental sustainability, resource sustainability, social sustainability, and economic sustainability. Furthermore, the difference-in-differences approach is applied to verify the treatment effect. Liaoning Province is chosen as the control group because it is also the traditionally agricultural province, and it has not implemented any large-scale water management projects. This study selects six sustainable variables, i.e., per capita GDP, urban-rural disparity, total water resources, domestic waste clearance, urbanization level, and health security level. The results show that the FWC project positively affects the sustainable development of agriculture for Zhejiang Province in economic sustainability, ecological sustainability, and social sustainability.


Asunto(s)
Conservación de los Recursos Naturales , Desarrollo Sostenible , Agricultura , China , Monitoreo del Ambiente , Agua
7.
ACS Appl Mater Interfaces ; 13(9): 11524-11534, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33635048

RESUMEN

Tribofilm configuration under the boundary lubrication region is an essential concern to gain insight into the tribological enhancement of the two-dimensional (2D) nano materials toward base oils. In this work, several alkyl carboxylic acids modified 2D triazine-based covalent organic frameworks (ATC) nano platelets were fabricated and served as lubrication additives. When carbon atoms add up to 16, the best lubricating performance is exhibited at an additive concentration of 0.05 wt % and the friction coefficient and wear volume are, respectively, reduced by 56.0% and 89.6% as compared to those of pure PAO 10 base oil. The analysis of the focused ion beam-transmission electron microscope (FIB-TEM) on the worn surface reveals that an alternately multilayer tribofilm consisting of 2D platelet additives and oxides and/or metallic soap salts is formed on the frictional interface of steel substrate, with a well-ordered arrangement along the sliding direction, which dominates the contributions of the excellent lubrication.

8.
J Food Sci Technol ; 56(1): 114-121, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30728552

RESUMEN

Shewanella baltica is the predominant bacteria in spoiled shrimp (Litopenaeus vannamei), however, the spoilage ability and the mechanism of S. baltica is still unknown. S. baltica can't produce the signal molecule of acyl-homoserine-lactones (AHLs), so the aim of this study was to investigate how wild type S. baltica SA03 (WT SA03) eavesdrop exogenous AHLs to enhance its spoilage ability through LuxR receptor. The results indicated that Aeromonas spp. (Aer), Acinetobacter spp. (Aci) and Serratia spp. (Ser) isolated from refrigerated shrimp can produce different AHLs. WT SA03 can eavesdrop the AHLs of Aer (C4-HSL), Aci (O-C6-HSL) and Ser (C6-HSL, O-C6-HSL) to enhance its growth, especially Ser. Exogenous C4-HSL and C6-HSL enhanced biofilm formation of WT SA03, and C6-HSL and O-C6-HSL enhanced thioredoxin reductase trxB mRNA expression. However, the luxR mutant of WT SA03 (ΔluxR SA03) lost or weakened the role of using environmental AHLs. In vivo experiments, the lag time of WT SA03 was shortened by 6.4 h, 6.2 h and 14.4 h by co-inoculated with Aer, Aci and Ser, respectively. The total volatile basic nitrogen (TVB-N) were significantly enhanced in the samples co-inoculated with WT SA03 and Aer (or Aci, Ser) than those of ΔluxR SA03 and Aer (or Aci, Ser) (p < 0.05). The results showed that S. baltica SA03 can utilize AHLs produced by other bacteria to enhance its growth and spoilage ability through LuxR receptor system. Quorum sensing based on AHLs of bacteria might as the potential targets for food spoilage control.

9.
J Food Sci Technol ; 55(7): 2795-2800, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30042596

RESUMEN

Numerous bacterial species utilize quorum sensing molecules acyl-homoserine-lactones (AHLs) to communicate, however, crosstalk often complicates the dynamics and behaviors of mixed populations. In this study, we developed a luxR mutant of wild type Shewanella baltica SA03 (WT SA03), and aimed to investigate the role of S. baltica LuxR (AHLs receptor) involved in the spoilage of refrigerated shrimp (Litopenaeus vannamei) by inoculating WT SA03 and luxR mutant of S. baltica SA03 (ΔluxR SA03), respectively. The results indicated the maximum growth rate of total viable bacteria in shrimp inoculated with ΔluxR SA03 was 73.34% lower than that of WT SA03. The lag time of total bacteria in shrimp treated with ΔluxR SA03 were 87.6 h, significantly longer than that of WT SA03. Meanwhile, the total volatile basic nitrogen concentrations of shrimp treated with WT SA03 were significantly higher than that of ΔluxR SA03 after 2 days of storage, which were in agreement with the decrease of the content of AHLs of the shrimp. The results indicated S. baltica might utilize AHLs produced by other bacteria and accelerate the shrimp spoilage process through LuxR receptor system.

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