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1.
J Am Chem Soc ; 146(12): 8098-8109, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38477574

RESUMO

Determining the structures of previously unseen compounds from experimental characterizations is a crucial part of materials science. It requires a step of searching for the structure type that conforms to the lattice of the unknown compound, which enables the pattern matching process for characterization data, such as X-ray diffraction (XRD) patterns. However, this procedure typically places a high demand on domain expertise, thus creating an obstacle for computer-driven automation. Here, we address this challenge by leveraging a deep-learning model composed of a union of convolutional residual neural networks. The accuracy of the model is demonstrated on a dataset of over 60,000 different compounds for 100 structure types, and additional categories can be integrated without the need to retrain the existing networks. We also unravel the operation of the deep-learning black box and highlight the way in which the resemblance between the unknown compound and a structure type is quantified based on both local and global characteristics in XRD patterns. This computational tool opens new avenues for automating structure analysis on materials unearthed in high-throughput experimentation.

2.
Langmuir ; 40(24): 12602-12612, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848496

RESUMO

The dynamic wetting behavior of droplets has been of wide concern due to the hazards of accretion/icing of supercooled droplets on engineering components/systems served in low temperature freezing rain environment; thus, it is urgent to establish the relationship between droplet depinning/removing behaviors and surface characteristics. In this article, the actual rotation conditions of moving components such as wind turbine blades are simulated. The self-cleaning hydrophobic coating surface(S1) and bionic superhydrophobic coating surface(S2) show outstanding droplet removal performance compared to hydrophilic bare steel surface(S0), and the average speed of the droplet removal is increased by 400-500%. The "creeping-sliding" behavior of droplets on self-cleaning coatings is investigated by the change of droplet displacement(ΔD). The effect of the energy storage caused by the droplet creeping process provides initial kinetic energy for the droplet removal. Combined with the experimental data and theoretical model, the critical depinning resistance is calculated. The difference of the wetting interface free energy(ΔEx) during the dynamic wetting process of the droplets on the bionic superhydrophobic self-cleaning surface is researched. And the influence mechanism of the droplet embedded depth(x) on the creeping/sliding behavior in the nanotexture is clarified. Thus, the mechanical criterion of droplet depinning is proposed (the error is about 10%). The results can provide a theoretical basis for the design principle of antifreezing rain coatings on moving components.

3.
Altern Ther Health Med ; 29(2): 174-179, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36455146

RESUMO

Context: Cardiovascular diseases (CVDs caused by atherosclerosis, such as coronary heart disease and stroke, have become major causes of death and disability worldwide. Atherosclerosis is the primary pathological factor causing CVDs. Managing weight, blood pressure, and lipids is one of the tenets of chronic-disease management, including atherosclerosis. Objective: The study intended to investigate the effects of managing weight, blood pressure, and lipids on disease severity in patients with carotid atherosclerosis. Design: The research team designed a randomized, controlled trial. Setting: The study took place in the pediatric department at the First Hospital of Hebei Medical University in Shijiazhuang, Hebei Province, China. Participants: Participants were 380 patients with carotid atherosclerosis who entered the hospital between March 2018 and June 2020. Intervention: Participants were randomly assigned, using the random-number-table method, to an intervention or a control group, with 190 participants in each group. Both groups received anti-atherosclerotic treatments, and the intervention group also took part in a program for combined management of weight, blood pressure, and blood lipids. Outcome Measures: All measurements occurred at baseline and postintervention. Using a questionnaire, the study measured the changes in the two groups related to alcohol consumption, smoking, high-fat diet, high-salt diet, and lack of exercise. A physical examination provided participants' weights, blood pressures, and lipid levels, and the Self-Care Ability Assessment Scale (ESCA) provided the changes in their self-management ability. A carotid-artery examination measured parameters related to carotid atherosclerosis, including intima-media thickness (IMT), Crouse scores, plaque-class scores, and plaque-grade scores. Results: At baseline, no statistically significant differences existed between the groups. Postintervention, the intervention group had significantly greater decreases than the control group for alcohol consumption, smoking, high-fat diet, high-salt diet, lack of exercise, weight, blood pressure, lipid levels, intima-media thickness (IMT) scores, Crouse scores, and plaque-grade scores. Postintervention, the intervention group had significantly greater increases than the control group for self-responsibility, health knowledge, self-concept, and self-care-skills scores. Conclusions: A program for management of body weight, blood pressure, and blood lipids can effectively control the severity of carotid atherosclerosis, can prevent the disease's progression, and can be promoted as a clinical application.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Criança , Humanos , Pressão Sanguínea , Espessura Intima-Media Carotídea , Fatores de Risco , Lipídeos , Gravidade do Paciente
4.
Vascul Pharmacol ; 157: 107416, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151593

RESUMO

OBJECTIVE: This study explores the association of serum 25-hydroxyvitamin D3 (25(OH)D3) levels with carotid artery intima-media thickness (CIMT), and the presence of carotid atherosclerotic plaques in individuals with a history of smoking. METHODS: A total of 469 patients suspected of having carotid atherosclerosis, aged 52 to 73 years with an average age of 65.26 ± 4.37 years, were recruited from the author's hospital from January 2023 to October 2023. All patients had a smoking history of nearly 5 years. Based on their serum 25(OH)D3 levels, they were divided into two groups: the normal group (serum level 30-50 ng/mL, n = 300) and the deficiency group (<30 ng/mL, n = 169). General details of the two patient groups were collected. Carotid artery ultrasound was employed to assess pulse wave velocity (PWV), carotid artery compliance coefficient (CC), and CIMT. Blood chemistry analysis measured serum lipid metabolism indicators including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HD-LC). The relationship between CIMT and each variable was analyzed through Pearson correlation, and logistic regression was used to identify risk factors influencing carotid artery plaque development. RESULTS: General patient information between the two groups showed no significant differences (P > 0.05). Patients in the 25(OH)D3 deficiency group exhibited elevated left and right PWV and CC compared to the 25(OH)D3 normal group (P < 0.05). The deficiency group exhibited larger CIMT and plaque area compared to the normal group (P < 0.05). Additionally, the deficiency group demonstrated higher levels of TC, LDL-C, and HD-LC compared to the normal group (P < 0.05). A moderate positive correlation was found between TC, LDL-C, and CIMT (P < 0.05), while a strong positive correlation existed between 25(OH)D3 and CIMT (P < 0.05). In smokers, the formation of carotid artery plaque was associated with factors such as patient age, CIMT, serum LDL-C, and 25(OH)D3 levels (P < 0.05). As age, CIMT, LDL-C levels increased, and 25(OH)D3 levels decreased, the risk of carotid plaques in smokers increased (P < 0.05). CONCLUSIONS: Smokers with lower 25(OH)D3 levels exhibit higher CIMT and more prominent carotid atherosclerotic plaques, indicating increased arterial stiffness and elevated cardiovascular risk. These findings demonstrate crucial implications that insufficient levels of vitamin D may potentially contribute to a higher risk of atherosclerosis among smokers.

5.
Psychol Res Behav Manag ; 16: 419-430, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819008

RESUMO

Purpose: The school climate, which refers to the quality and character of school life, is associated with a wide range of developmental outcomes. Although researchers have shown considerable interest in uncovering the links between school climate and prosocial behavior, the mechanisms underlying this association remain unclear. Therefore, the current study was designed to investigate the mediating role of gratitude between school climate and adolescents' prosocial behavior. Methods: A sample of 632 Chinese adolescents (363 girls and 269 boys; Mage = 16.83 years at time 1, SD = 0.68 years) completed a battery of sociometric and self-report questionnaires that measured school climate, gratitude, and prosocial behavior in three waves. Results: Correlation analysis showed that school climate, gratitude, and prosocial behavior were all significantly and positively intercorrelated across the three waves. Importantly, gratitude completely mediated the relationship between school climate and prosocial behavior (ß = 0.005 [95% confidence interval = 0.001, 0.013]) in the three-wave longitudinal mediation model. Conclusion: As a positive disposition, gratitude fosters prosocial behavior and serves as a mediator between school climate and prosocial behavior. This study provides a theoretical explanation for cultivating adolescents' prosocial behavior and theoretical guidelines for interventions of schools and other socializing agents.

6.
Biomed Res Int ; 2022: 8282624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909487

RESUMO

To detect the expression of inflammatory factors such as interleukin-1ß (IL-1ß), interleukin-6 (IL-6), transforming growth factor (TGF-ß), and tumor necrosis factor (TNF-α) in the tumor tissue of ventricular septal defect (VSD) in congenital heart disease and to explore the role of inflammatory response in the formation of aneurysmal perimembranous VSD(APVSD). Children with APVSD of congenital heart disease treated by surgery were selected and divided into true aneurysmal perimembranous group (TAP group) and pseudoaneurysmal perimembranous group (PAP group) according to echocardiography and surgical findings. There were 15 children in the TAP group and 31 in the PAP group. The aneurysmal perimembranous tissue of the two groups of children was collected during the operation. IL-1ß, IL-6, TGF-ß, and TNF-α were positively expressed in the aneurysmal perimembranous tissue of the two groups, and the expression levels of all inflammatory factors in the PAP group were higher than those in the TAP group, and the difference was statistically significant (P < 0.05). The expression levels of IL-1ß, IL-6, TGF-ß, and TNF-α in the aneurysmal perimembranous tissue of the two groups were negatively correlated with the width of the APVSD breach. IL-1ß, IL-6, TGF-ß, and TNF-α may be involved in the occurrence and development of APVSD through inflammatory mechanism.


Assuntos
Comunicação Interventricular , Fator de Necrose Tumoral alfa , Criança , Ecocardiografia , Comunicação Interventricular/diagnóstico por imagem , Comunicação Interventricular/cirurgia , Humanos , Interleucina-6 , Fator de Crescimento Transformador beta
7.
J Phys Chem A ; 114(1): 443-54, 2010 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-20017479

RESUMO

The complexation reactions of ethylenediaminetetraacetate (EDTA(4-)) and S,S-ethylenediaminedisuccinate (S,S-EDDS(4-)) with Co(2+), Ni(2+), Cu(2+), Zn(2+), and Cd(2+) cations are investigated by using the DFT/B3LYP method. The hydration reaction of each metal ion with solvent water cluster is considered with a mixed cluster/continuum model. The subsequent metal complexation is treated as a substitution reaction of the coordinated water molecules by the amino polycarboxylic acid ligand. Thermodynamic cycles are schemed to evaluate the free energy changes for both hydration and complexation processes. The values of complexation free energy changes show that the stabilities of metal complexes with the isomeric ligands follow the order of [M(S,S-EDDS)](2-) in trans(O(6))-conformer < [M(S,S-EDDS)](2-) in trans(O(5))-conformer < [M(EDTA)](2-), implying that the failure to observe the trans(O(6)) conformer under experimental conditions is attributed to its inherent instability. The same trend appears in our steric strain analysis on the various chelate rings in complexes. Because the [M(S,S-EDDS)](2-) in trans(O(6)) complex is not available, we focus on the other two series of complexes with concerned metal ions. The stabilities decrease in the order Cu(2+) > Ni(2+) > Co(2+) > Zn(2+) > Cd(2+) and Cu(2+) > Ni(2+) > Co(2+) > Cd(2+) > Zn(2+) for trans(O(5))-[M(S,S-EDDS)](2-) and [M(EDTA)](2-), respectively. These two tendencies are shown to be consistent with the decrease in the metal-to-ligand charge transfer. Meanwhile, a good quantitative correlation is found between the complexation free energies and the dipole moments for all complexes (excluding the case of Cu(2+)). The far-infrared spectra are present to investigate the characteristics of metal-dependent vibrations, and the further natural bond orbital (NBO) method is taken to show the nature of metal-ligand bonding interactions. Finally, and perhaps most importantly, degrading products of both amino polycarboxylic acids are successfully predicted through calculating the dissociation energies of all C-N bonds in free EDTA, S,S-EDDS, and their successive products. Degradation mechanisms with intramolecular hydrogen transfer are proposed for the biodegradation reactions of S,S-EDDS and its product N-(2-aminoethyl) aspartic acid (AEAA).


Assuntos
Simulação por Computador , Ácido Edético/química , Etilenodiaminas/química , Metais Pesados/química , Modelos Químicos , Compostos Organometálicos/química , Succinatos/química , Ácido Edético/metabolismo , Etilenodiaminas/metabolismo , Ligantes , Metais Pesados/metabolismo , Compostos Organometálicos/metabolismo , Teoria Quântica , Succinatos/metabolismo , Termodinâmica , Água/química
8.
Colloids Surf B Biointerfaces ; 61(2): 170-5, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17869490

RESUMO

Bacterial-mineral composites are important in the retention of heavy metals due to their large sorption capacity under a wide range of environmental conditions. This study provides the first quantitative comparison of the metal-binding capacities of P. putida CZ1-goethite composite to its individual components. When the same amount (on a dry weight basis) of living and nonliving cells of P. putida CZ1, goethite or their composites was separately exposed to solutions of 0.5 mM Cu(II) and Zn(II) in 0.01 M KNO(3), the living cells removed the largest quantity of heavy metals. The results of calculated metal retention values indicated that the adsorption of goethite to bacteria has not mask or neutralize chemically reactive adsorption sites normally available to metal ions. Moreover, the nonliving cells-goethite composite retained approximately 82% more Zn than that predicted by their individual behavior. The preferential association of Zn with P. putida CZ1 was observed by TEM and EDS analyses of a mixture consisting of the bacteria and goethite. Desorption of Cu and Zn with 1.0M CH(3)COOK solution from P. putida CZ1 and goethite indicated the differences in the functional groups able to bind heavy metals.


Assuntos
Recuperação e Remediação Ambiental , Compostos de Ferro/metabolismo , Metais Pesados/metabolismo , Pseudomonas putida/metabolismo , Adsorção , Silicatos de Alumínio , Argila , Viabilidade Microbiana , Minerais , Pseudomonas putida/citologia , Pseudomonas putida/ultraestrutura , Soluções
9.
ACS Appl Mater Interfaces ; 9(40): 34990-35000, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28930434

RESUMO

The continuous solid solution NiWOx is successfully prepared by using precursor W18O49 with plenty of oxygen defects. The NiWOx nanoparticles are characterized by X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray absorption spectroscopy. The crystallographic phase of NiWOx is stable and characterized by the same feature of the parent lattice W18O49 even with various concentrations of dopant Ni which indicates the existence of oxygen defects. The NiWOx nanoparticles could be processed as the appropriate promoter after loading 10 wt % Pt. The Pt/NiWOx displays remarkable response for oxygen reduction reaction in alkaline medium compared with the commercial Pt/C. The analysis of the electrochemistry data shows that the existence of abundant oxygen defects in the solid solution NiWOx is the key factor for the improved ORR catalyst performance. Ni is effective in the catalysts because of its compatibility with W in the solid solution and its active participation in oxygen reduction reaction.

10.
Int J Environ Res Public Health ; 11(3): 3118-31, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24637907

RESUMO

Due to the emerging environmental issues related to e-waste there is concern about the quality of paddy soils near e-waste workshops. The levels of heavy metals and PCBs and their influence on the enzyme activity and microbial community of paddy soils obtained from the immediate vicinity of an e-waste workshop were investigated in the present study. The results indicated that the heavy metal and PCB pollution did not differ significantly with an increase of the sampling point distances (5 to 30 m). The concentration of Cd (2.16 mg·kg-1) and Cu (69.2 mg·kg-1) were higher, and the PCB pollution was also serious, ranging from 4.9 to 21.6 µg·kg-1. The highest enzyme activity was found for urease compared to phosphatase and catalase, and a fluctuating trend in soil enzyme activity was observed in soils from different sampling sites. The microbial analysis revealed that there was no apparent correlation between the microbial community and the pollutants. However, a slight influence for soil microbial communities could be found based on DGGE, the Shannon index and PCA analysis. The present study suggests that the contamination stress of heavy metals and PCBs might have a slight influence on microbial activity in paddy soils. This study provides the baseline data for enzyme activities and microbial communities in paddy soil under the influence of mixed contamination.


Assuntos
Metais Pesados/toxicidade , Consórcios Microbianos/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Microbiologia do Solo , Poluentes do Solo/toxicidade , Resíduo Eletrônico , Enzimas/análise , Solo/química
11.
Appl Microbiol Biotechnol ; 74(4): 881-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17021877

RESUMO

Previously performed studies have shown that Pseudomonas putida CZ1 biomass can bind an appreciable amount of Cu(II) and Zn(II) ions from aqueous solutions. The mechanisms of Cu- and Zn-binding by P. putida CZ1 were ascertained by chemical modifications of the biomass followed by Fourier transform infrared and X-ray absorption spectroscopic analyses of the living or nonliving cells. A dramatic decrease in Cu(II)- and Zn(II)-binding resulted after acidic methanol esterification of the nonliving cells, indicating that carboxyl functional groups play an important role in the binding of metal to the biomaterial. X-ray absorption spectroscopy was used to determine the speciation of Cu ions bound by living and nonliving cells, as well as to elucidate which functional groups were involved in binding of the Cu ions. The X-ray absorption near-edge structure spectra analysis showed that the majority of the Cu was bound in both samples as Cu(II). The fitting results of Cu K-edge extended X-ray absorption fine structure spectra showed that N/O ligands dominated in living and nonliving cells. Therefore, by combining different techniques, our results indicate that carboxyl functional groups are the major ligands responsible for the metal binding in P. putida CZ1.


Assuntos
Cobre/metabolismo , Pseudomonas putida/metabolismo , Absorciometria de Fóton , Células Procarióticas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Zinco/metabolismo
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