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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123932, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38266606

RESUMEN

Perfluorooctanoic acid (PFOA), a novel organic pollutant, has been shown to be toxic, persistent, bioaccumulative, long-range transportable, and globally prevalent. This article is based on surface enhanced Raman scattering (SERS) spectroscopy analysis technology. The monolayer of SiO2 was prepared by chemical reduction etching self-assembly method and silver dendrites were grown on it, thus forming the SERS substrate with silver dendrite Metasurface structure with Raman detection enhancement factor up to 2.32 × 105. The prepared silver dendrite Metasurface SERS substrate was applied to the qualitative and quantitative detection of PFOA, with a quantitative detection limit of 15.89 ppb. The results of this paper provide a new, simple, and quick method for the detection of PFOA in the environment.

2.
PLoS One ; 17(7): e0269089, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35793371

RESUMEN

As a result of business environment reforms in China's Hangzou, the cost of business has reduced, the confidence of Hangzhou enterprises has survived the COVID-19 outbreak, and foreign investment continues to increase. Nevertheless, Hangzhou's business environment has shortcomings, such as insufficient technology, talent, and intelligent infrastructure. Two unresolved questions persist: (i) Has the smart business environment stimulated corporate investment by reducing system costs and boosting corporate confidence? (ii) How do the commercial climate's shortcomings impact the relationship between the intelligent business environment and business costs/confidence? We examined the impact of a local smart business environment on the corporate investment scale in Hangzhou using factor analysis, cluster analysis, linear regression, and path analyses of data from 297 firm managers. Smart governance improved public administration, financing, and rule of law. The business environment promoted investment by increasing business confidence and decreasing institutional costs. Weak intelligent property protection and legal fairness hindered the positive influence of smart governance on business confidence and system costs. This is the first study combining business environment, smart city, and smart governance concepts to analyze the influence of local smart business environments on business confidence, institutional costs, and investment. Our conclusion on the limitation effect of intelligent business environment on enterprise investment attempts to inspire further research on the intersection of business environments and smart cities. The law of intelligent business environment attracting investment obtained in the context of China, the largest developing country with diversified economic development, is of great significance for other developing countries. Countries can attract investment and promote economic development through intelligent governance. Developing countries should construct smart service platforms, coordinate supervision of public credit, reduce financing constraint, construct a government under the rule of law, improve the quality of land management, and protect intellectual property rights.


Asunto(s)
COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Comercio , Desarrollo Económico , Humanos , Inversiones en Salud , Organizaciones
3.
Front Endocrinol (Lausanne) ; 13: 890900, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36704031

RESUMEN

Introduction: This study aimed to investigate the relationship between Oxford Classification scores and longitudinal changes in proteinuria in patients with immunoglobulin A nephropathy (IgAN). Methods: The study was a single-center retrospective cohort study involving 358 patients with primary IgAN who were treated at the Shenzhen Second People's Hospital, China, between January 2011 and May 2021. Multivariate linear regression and generalized additive mixed models (GAMMs), adjusted for traditional risk confounders, were used to evaluate the correlation between scores for mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy/interstitial fibrosis (T), and crescents (C) (known as the Oxford Classification MEST-C score system), with proteinuria/creatinine ratio (PCR) at the time of renal biopsy and longitudinal changes in PCR, respectively. Results: The median PCR was 1061 mg/g, and it increased on average by 68.82 mg/g per year in these patients. Among patients with renal insufficiency, compared with patients without relative lesions, those with E present (E1) (1153.44; 95% confidence interval [CI], 188.99-2117.89 mg/g) and C > 0 (C1/2) (1063.58; 95% CI, 185.25-1941.90 mg/g) were associated with increased PCR levels at the time of renal biopsy. What's more, S present (S1) (194.96; 95% CI, 54.50-335.43 mg/g per year) was associated with the fastest PCR increase; C > 0 (C1/2) (147.59; 95% CI, 8.32-286.86 mg/g per year) and T >25% (T1/2) (77.04; 95% CI, 7.18-146.89 mg/g per year), were also correlated with a faster PCR increase. In patients with normal kidney function, associations between S1 (55.46; 95% CI, 8.93-101.99 mg/g per year) and E1 (94.02; 95% CI, 21.47-166.58 mg/g per year) and PCR change could be observed. Additionally, in patients with overweight/obesity, S1 (156.09; 95% CI, 52.41-259.77 mg/g per year), E1 (143.34; 95% CI, 35.30-251.38 mg/g per year), T1/2 (116.04; 95% CI, 22.58-209.51 mg/g per year), as well as C1/2 (134.03; 95% CI, 41.73-226.32 mg/g per year) were associated with noticeably quicker PCR increase. Conclusions: Overall, E1 and C1/2 were independently associated with raised proteinuria levels at the time of renal biopsy, and S1, E1, T1/2, C1/2 were independently associated with a longitudinal increase in proteinuria in the patients with IgAN, especially in those with renal insufficiency or overweight/obesity, suggesting that currently available treatments might not be satisfactory, and weight control might be beneficial. Individual therapy development might benefit from the use of the Oxford Classification system.


Asunto(s)
Glomerulonefritis por IGA , Insuficiencia Renal , Humanos , Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/patología , Estudios Retrospectivos , Sobrepeso , Proteinuria/etiología , Proteinuria/patología , Obesidad
4.
World J Diabetes ; 12(11): 1917-1927, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34888016

RESUMEN

BACKGROUND: Anaemia is common in patients with chronic kidney disease (CKD) and is a major risk factor that contributes to mortality in such patients. Type 2 diabetes mellitus (T2DM) is one of the leading causes of CKD. The association between admission hemoglobin levels and renal damage in patients with T2DM remains unclear. AIM: To evaluate the relationship between admission hemoglobin levels and prognosis in patients with T2DM. METHODS: We performed a retrospective analysis of 265 consecutive patients presenting with T2DM between 2011 and 2015. The composite endpoint was end-stage renal disease or a 50% reduction in the estimated glomerular filtration rate. RESULTS: In multivariable-adjusted Cox proportional hazards models (adjusting for demographic factors, traditional risk factors, lipids), the adjusted hazard ratios (HRs) for the highest and middle tertiles compared to the lowest tertile of hemoglobin were 0.82 (95%CI: 0.11-6.26, P = 0.8457) and 0.28 (95%CI: 0.09-0.85, P = 0.0246), respectively. However, after further adjustment for glycaemia control, hemoglobin was positively related to the risk of the composite endpoint (HR: 1.05, 95%CI: 0.14-8.09, P = 0.9602) when the highest tertile was compared to the lowest tertile of hemoglobin. We found a U-shaped relationship between hemoglobin levels and the composite endpoint. The curve tended to reach the lowest level at an optimal hemoglobin level. CONCLUSION: Among patients with T2DM, a U-shaped relationship was observed between hemoglobin levels and renal damage. A lower admission hemoglobin level (hemoglobin < 13.3 g/dL) is an independent predictor of renal damage.

5.
Opt Express ; 24(11): 12151-65, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27410135

RESUMEN

We present that surface two-plasmon resonance (STPR) in electron plasma sheet produced by a femtosecond laser irradiating a solid surface is the self-formation mechanism of periodic subwavelength ripple structures. Peaks of overdense electrons, formed by resonant two-plasmon wave mode, pull bound ions out of the metal surface. Thus, the wave pattern of STPR is "carved" on the surface by Coulomb ablation (removal) due to periodic distributed strong electrostatic field produced by charge separation. To confirm the STPR model, we have performed analogical carving experiments by two femtosecond laser beams with perpendicular polarizations and time delay. The results explicitly show that two wave patterns of STPR generated by each beam are independently created in the pulse exposure area of a target surface, which is like the traditional "layer-carving" technique by comparison with the structured topological features. The time-scale of ablation dynamics and the electron temperature in ultrafast interaction are also verified by a time-resolved spectroscopy experiment and numerical simulation, respectively. The present model can self-consistently explain the formation of subwavelength ripple structures even with spatial periods shorter than half of the laser wavelength, shedding light on the understanding of ultrafast laser-solid interaction.

6.
Opt Express ; 21(5): 5413-23, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23482112

RESUMEN

A recombination rate of electron-ion in the strong-field atomic process is phenomenologically introduced into the ionization rate equation, and therefrom an ionization and recombination rates equation (IRRE) is obtained. By using the extended IRRE, the propagation equation of an intense femtosecond laser pulse in the gaseous medium is re-derived. Some new physical behaviors and characteristics caused by the introduced recombination rate are discussed in detail.

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