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1.
Heliyon ; 10(7): e28119, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601615

RESUMO

Background: The association between dietary vitamin B1 intake and cognitive performance in the noninstitutionalized older adult population of the United States remains unclear. Purpose: This study aimed to investigate the association between vitamin B1 intake and cognitive performance in older adults in the United States. Methods: Vitamin B1 intake was assessed through two 24-h dietary recalls. Weighted logistic regression was used to evaluate the association between vitamin B1 intake and three cognitive scores (immediate recall test [IRT], animal fluency test [AFT], and digit symbol substitution test [DSST]). Cognitive performance was measured by these three tests, and individuals scoring below the lowest quartile were categorized as cognitive impairment. Sensitivity analysis, including dose-response curves, subgroup analyses, interaction effects, per 1 SD, and quartiles, were performed to ensure the accuracy of the conclusion. Results: A total of 2896 participants over the age of 60 were included in this study. In the adjusted final model, the association between vitamin B1 intake and low cognitive performance in old age was statistically significant, with the following odds ratios (ORs) and 95% confidence intervals (CIs): IRT, 0.75 (0.57, 0.97), P = 0.018; AFT, 0.68 (0.50, 0.92), P = 0.007; DSST, 0.71 (0.54, 0.92), P = 0.005. Subgroup analyses showed that this association was statistically significant among males, white, low-education, and no memory impairment. The results of the sensitivity analyses confirmed the association between VB1 and cognitive function in old age and the absence of interactions in the final calibrated model. Conclusion: Dietary vitamin B1 intake is negatively associated with cognitive performance in older adults.

2.
BMC Surg ; 24(1): 39, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291417

RESUMO

BACKGROUND: This study aimed to analyze the effect of surgical compliance on the survival outcome of patients with meningioma and explore the factors affecting surgical compliance. METHODS: We selected data from the Surveillance, Epidemiology, and End Results database for 122,632 meningioma patients diagnosed between 2004 and 2018. The effect of surgical compliance on patients' overall survival (OS) was analyzed through Cox regression and Kaplan-Meier curves. Independent risk factors for surgical compliance were identified through multifactorial logistic regression analyses to construct diagnostic nomograms, further assessed by receiver operating characteristic curves. Furthermore, we used univariate and multivariate logistic regression analyses to evaluate relevant variables linked to adherence with meningioma surgery. Moreover, 1:1 propensity score matching was applied to assess the validity of the results in patients with favorable and poor surgical compliance. RESULTS: A total of 48,735 were eligible from the initial cohort of 122,632 patients with meningioma. Among them, 45,038 (92.40%) exhibited good surgical compliance, while 3697 (7.60%) had poor surgical compliance. The rate of patients with good surgical compliance was significantly higher than that of patients with inadequate surgical compliance (p < 0.001). Moreover, surgical compliance is an independent prognostic factor for OS in meningioma patients. Univariate Cox regression analysis indicated that individuals with poor surgical compliance demonstrated lower OS rates than those with good surgical compliance (hazard ratio [HR 2.404; 95% confidence interval [CI] 2.276-2.54, p < 0.001], consistent with the observation in the multivariate analysis (HR 1.564; 95% CI 1.471-1.663, p < 0.001). We developed a prediction model using seven variables: age, sex, race, tumor behavior recode, tumor size, family income, and residential setting (p < 0.05). Surgical compliance was associated with patient age, sex, race, tumor behavior recode, tumor size, family income, and residential setting by logistic regression analysis. CONCLUSIONS: Surgical compliance emerged as an independent prognostic factor for survival in patients with meningioma. Poor surgical compliance was associated with older age, black and other races, females, advanced-stage tumors, larger tumor size, lower household income, and rural residence. When patients experienced these conditions, OS was shorter, requiring more aggressive treatment.


Assuntos
Neoplasias Meníngeas , Meningioma , Feminino , Humanos , Meningioma/cirurgia , Pontuação de Propensão , Estudos Retrospectivos , Nomogramas , Fatores de Risco , Neoplasias Meníngeas/cirurgia , Prognóstico
3.
Front Neurosci ; 17: 1276032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027501

RESUMO

Background: This study aimed to investigate putative causal effects between constipation and stroke using bidirectional Mendelian randomization (MR) analysis. Methods: Based on the cross-sectional study, logistic regression models were developed to assess the association between constipation and stroke prevalence. Subsequently, genome-wide association studies statistics were employed to perform MR analysis between constipation and stroke, as well as its subtypes. The inverse variance weighting (IVW) method was the primary method, complemented by four additional methods, namely weighted median, weighted mode, simple mode, and MR-Egger regression. Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier, and MR Steiger test were performed to assess heterogeneity and pleiotropy effects. Results: Constipation was associated with a greater risk of stroke even after adjusting for all covariates in logistic regression [odds ratio (OR) = 1.46, 95% confidence interval (CI) = 1.01-2.09, p = 0.042]. IVW MR analysis revealed that constipation affected large artery atherosclerosis (LAS; IVW OR = 1.5, 95% CI = 1.07-2.104, p = 0.019). No significant or suggestive association was observed with the risk of stroke or its various subtypes in MR analysis. Meanwhile, reverse MR analysis revealed no significant causal relationship between stroke or other stroke subtypes and constipation. The results of sensitivity analyses revealed no significant horizontal pleiotropy affecting causal estimates. Conclusion: While cross-sectional studies have established that constipation increases the risk of stroke, this two-sample bidirectional MR analysis revealed a positive correlation between constipation and LAS. However, no such correlation was observed between constipation and stroke, including its various subtypes.

5.
Anal Sci ; 38(4): 711-716, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35434761

RESUMO

An investigation of the process involved in the production of and dyeing with indigo based on a CO2/O2 sensor device and a cellphone-camera is reported. The former involves transforming indican to indigo, and the latter the process by which indigo and indigo-white are produced. During the process of indigo production, a clear and positive correlation can be observed between the concentration of gas levels (either the production of CO2 or the consumption of O2) and the final yield. The authors found that for the first time that the change in the concentration levels of CO2/O2 can be used as important parameters for indigo dyeing. The optimal time required to produce indigo can be decided by the change of CO2/O2 concentration level. It is no long should depending on the experience of a craftsperson. Furthermore, the optimal time needed to produce indigo also can be decided by the concentration levels of glucose. The color analysis of indigo dyeing can be performed by using a camera and by calculating the RGB and HSV (hue, saturation, value) values.


Assuntos
Telefone Celular , Índigo Carmim , Dióxido de Carbono , Corantes , Indóis
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 240: 118598, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32563034

RESUMO

Nitrogen and sulfur co-doped carbon dots (N/S-CDs) were prepared by a simple hydrothermal method using gardenia fruit as precursor. The N/S-CDs are nearly spherical particles with a size of 2.1 nm and possess excellent fluorescence stability in a wide pH range and high NaCl concentrations, as well as under UV light irradiation. The absolute quantum yield (QY) without any surface modification reaches up to 10.7%. Meanwhile, the N/S-CDs can be quenched by Hg2+ (turn-off), while the quenched fluorescence can be recovered (turn-on) by introducing cysteine (Cys), with linear ranges of 2-20 µM for Hg2+and 0.1-2.0 µM for Cys. On the basis of the on-off-on sensing mode, the N/S-CDs can be used to detect Hg2+ and Cys. Hence, the N/S-CDs would be a promising sensor in environmental and biological analysis.


Assuntos
Gardenia , Mercúrio , Pontos Quânticos , Carbono , Cisteína , Corantes Fluorescentes , Frutas , Nitrogênio , Espectrometria de Fluorescência
7.
J Colloid Interface Sci ; 543: 263-272, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30818142

RESUMO

Liquid phase exfoliation (LPE) method has great potential for the large-scale production of graphene due to its simplicity, scalability, and low cost. In this work, fulvic acid (FA) was chosen to assist the exfoliation of graphite into graphene for the first time via sonication in aqueous medium. The concentration of obtained graphene dispersion can reach 0.63 ±â€¯0.04 mg mL-1. The graphene flakes mostly consisted of 1-5 layers with sizes range in submicron to micron and few defects in the basal-plane. The π-π interaction between graphene and FA, along with the electrostatic repulsion between negatively charged FA, played a major role in stabilization of the graphene dispersion. By adjusting the pH of graphene dispersion to 14, the nanosheets of graphene came to flocculation. The formed graphene slurry is favorable for storage and transportation due to the greatly decreased volume. The annealed coating of FA-graphene on aluminum sheets was used as corrosion inhibitor for aluminum in 0.5 M H2SO4 and 0.6 M NaCl solutions, with inhibition efficiencies of up to 85.5% and 99.4%, respectively. This shows that as-prepared graphene has great potential applications in the anti-corrosion of aluminum.

8.
Environ Monit Assess ; 186(10): 6039-46, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24859926

RESUMO

The concentrations of seven heavy metals (HMs) in jujube samples collected from Hetian region (HTR), Hami region (HMR), Erkesu region (ESR), Bayikuleng region (BLR), and Turpan region (TUR) were determined by inductively coupled mass spectrometry (ICP-MS). The accuracy and precision of the analytical method were confirmed by the certified reference material (GBW 07605). In general, the concentration of iron was higher than those of the other six metals in the investigated jujube samples. The Hazard Quotient (HQ) and Hazard Index (HI) were calculated to evaluate the noncarcinogenic health risk from individual metal and combined metals due to the dietary intakes via consumption of jujube. Both HQ and HI levels were far below 1, suggesting no noncarcinogenic risks for Xinjiang adults under the current consumption rates of the jujubes. Among the jujubes from five different regions, BLR jujube had the highest HQ and HI. Fe and As were the most concerning HMs in the investigated jujube samples due to their higher relative contributions to HIs.


Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos/estatística & dados numéricos , Metais Pesados/análise , Ziziphus/química , Adulto , China , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Frutas/química , Humanos , Medição de Risco
9.
J Chem Phys ; 125(14): 144301, 2006 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-17042584

RESUMO

Following photodissociation of fluorobenzene (C6H5F) at 193 and 157 nm, we detected the products with fragmentation-translational spectroscopy by utilizing a tunable vacuum ultraviolet beam from a synchrotron for ionization. Between two primary dissociation channels observed upon irradiation at 193 (157) nm, the HF-elimination channel C6H5F --> HF + C6H4 dominates, with a branching ratio of 0.94+/-0.02 (0.61+/-0.05) and an average release of kinetic energy of 103 (108) kJ mol(-1); the H-elimination channel C6H5F --> H + C6H4F has a branching ratio of 0.06+/-0.02 (0.39+/-0.05) and an average release of kinetic energy of 18.6 (26.8) kJ mol(-1). Photofragments H, HF, C6H4, and C6H4F produced via the one-photon process have nearly isotropic angular distributions. Both the HF-elimination and the H-elimination channels likely proceed via the ground-state electronic surface following internal conversion of C6H5F; these channels exhibit small fractions of kinetic energy release from the available energy, indicating that the molecular fragments are highly internally excited. We also determined the ionization energy of C6H4F to be 8.6+/-0.2 eV.

10.
J Chem Phys ; 123(22): 224304, 2005 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-16375473

RESUMO

Following the photodissociation of o-fluorotoluene [o-C(6)H(4)(CH(3))F] at 193 nm, rotationally resolved emission spectra of HF(1< or =v< or =4) in the spectral region of 2800-4000 cm(-1) are detected with a step-scan Fourier transform spectrometer. HF(v< or =4) shows nearly Boltzmann-type rotational distributions corresponding to a temperature approximately 1080 K; a short extrapolation from data in the period of 0.5-4.5 mus leads to a nascent rotational temperature of 1130+/-100 K with an average rotational energy of 9+/-2 kJ mol(-1). The observed vibrational distribution of (v=1):(v=2):(v=3)=67.6: 23.2: 9.2 corresponds to a vibrational temperature of 5330+/-270 K. An average vibrational energy of 25+/-(3) (12) kJ mol(-1) is derived based on the observed population of HF(1< or =v< or =3) and estimates of the population of HF (v=0 and 4) by extrapolation. Experiments performed on p-fluorotoluene [p-C(6)H(4)(CH(3))F] yielded similar results with an average rotational energy of 9+/-2 kJ mol(-1) and vibrational energy of 26+/-(3) (12) kJ mol(-1) for HF. The observed distributions of internal energy of HF in both cases are consistent with that expected for four-center elimination. A modified impulse model taking into account geometries and displacement vectors of transition states during bond breaking predicts satisfactorily the rotational excitation of HF. An observed vibrational energy of HF produced from fluorotoluene slightly smaller than that from fluorobenzene might indicate the involvement of seven-membered-ring isomers upon photolysis.

11.
J Chem Phys ; 123(7): 074326, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16229589

RESUMO

Following photodissociation of formyl fluoride (HFCO) at 193 nm, we detected products with fragmentation translational spectroscopy utilizing a tunable vacuum ultraviolet beam from a synchrotron for ionization. Among three primary dissociation channels observed in this work, the F-elimination channel HFCO-->HCO+F dominates, with a branching ratio approximately 0.66 and an average release of kinetic energy approximately 55 kJ mol(-1); about 17% of HCO further decomposes to H+CO. The H-elimination channel HFCO-->FCO+H has a branching ratio approximately 0.28 and an average release of kinetic energy approximately 99 kJ mol(-1); about 21% of FCO further decomposes to F+CO. The F-elimination channel likely proceeds via the S1 surface whereas the H-elimination channel proceeds via the T1 surface; both channels exhibit moderate barriers for dissociation. The molecular HF-elimination channel HFCO-->HF+CO, correlating with the ground electronic surface, has a branching ratio of only approximately 0.06; the average translational release of 93 kJ mol(-1), approximately 15% of available energy, implies that the fragments are highly internally excited. Detailed mechanisms of photodissociation are discussed.

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