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1.
Ren Fail ; 45(2): 2285865, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994450

RESUMO

OBJECTIVE: Identifying patients at high risk for cardiac arrest-associated acute kidney injury (CA-AKI) helps in early preventive interventions. This study aimed to establish and validate a high-risk nomogram for CA-AKI. METHODS: In this retrospective dataset, 339 patients after cardiac arrest (CA) were enrolled and randomized into a training or testing dataset. The Student's t-test, non-parametric Mann-Whitney U test, or χ2 test was used to compare differences between the two groups. Optimal predictors of CA-AKI were determined using the Least Absolute Shrinkage and Selection Operator (LASSO). A nomogram was developed to predict the early onset of CA-AKI. The performance of the nomogram was assessed using metrics such as area under the curve (AUC), calibration curves, decision curve analysis (DCA), and clinical impact curve (CIC). RESULTS: In total, 150 patients (44.2%) were diagnosed with CA-AKI. Four independent risk predictors were identified and integrated into the nomogram: chronic kidney disease, albumin level, shock, and heart rate. Receiver operating characteristic (ROC) analyses showed that the nomogram had a good discrimination performance for CA-AKI in the training dataset 0.774 (95%CI, 0.715-0.833) and testing dataset 0.763 (95%CI, 0.670-0.856). The AUC values for the two groups were calculated and compared using the Hanley-McNeil test. No statistically significant differences were observed between the groups. The calibration curve demonstrated good agreement between the predicted outcome and actual observations. Good clinical usefulness was identified using DCA and CIC. CONCLUSION: An easy-to-use nomogram for predicting CA-AKI was established and validated, and the prediction efficiency of the clinical model has reasonable clinical practicability.


Assuntos
Injúria Renal Aguda , Parada Cardíaca , Humanos , Estudos Retrospectivos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Área Sob a Curva , Parada Cardíaca/etiologia , Frequência Cardíaca
2.
Molecules ; 28(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894557

RESUMO

Ag nanoparticles sputtered on silicon wafer are used as masks for the fabrication of silicon columns by ion etching, which induces the growth of the inclined Ag nanorod by inclined Ag sputtering. V-shaped and Z-shaped Ag nanorods can be obtained by varying incline angles and deposition times. SERS detection and FDTD simulation are used to compare and investigate the enhanced electromagnetic coupling of incline nanorod arrays with different shapes in three-dimensional space, which indicates that Z-shaped nanorods show good SERS properties. The Z-shaped Ag nanorod array is used as a SERS substrate for the detection of thiabendazole with a concentration down to 10-11 M.

3.
Opt Express ; 30(2): 2610-2625, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209397

RESUMO

Plasmonic nanocavities offer prospects for the amplification of inherently weak nonlinear responses at subwavelength scales. However, constructing these nanocavities with tunable modal volumes and reduced optical losses remains an open challenge in the development of nonlinear nanophotonics. Herein, we design and fabricate three-dimensional (3D) metal-dielectric-metal (MDM) plasmonic nanocavities that are capable of amplifying second-harmonic lights by up to three orders of magnitude with respect to dielectric-metal counterparts. In combination with experimental estimations of quantitative contributions of constituent parts in proposed 3D MDM designs, we further theoretically disclose the mechanism governing this signal amplification. We discover that this phenomenon can be attributed to the plasmon hybridization of both dipolar plasmon resonances and gap cavity resonances, such that an energy exchange channel can be attained and helps expand modal volumes while maintaining strong field localizations. Our results may advance the understanding of efficient nonlinear harmonic generations in 3D plasmonic nanostructures.

4.
Opt Express ; 30(21): 38256-38265, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258397

RESUMO

Metal-dielectric heterostructures have shown great application potentials in physics, chemistry and material science. In this work, we have designed and manufactured ordered metal-dielectric multiple heterostructures with tunable optical properties, which can be as large as the order of square centimeters in size. We experimentally realized that the surface-enhanced Raman scattering signal of the periodic multiple heterostructures increased 50 times compared with the silicon nanodisk-gold film arrays, which is attributed to the large-scale hotspots and high efficient coupling between the optical cavities and surface plasmon resonance modes. More importantly, the substrate also features a good uniformity and an excellent reproducible fabrication, which is very promising for practical applications.

5.
Langmuir ; 38(45): 13753-13762, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36331054

RESUMO

It is very important to build uniform large-area dense hotspots to improve the surface-enhanced Raman scattering (SERS) detection limit. In our research, we designed and prepared a new flexibile SERS substrate with ultradense hot spots that has the advantages of high sensitivity, good repeatability, easy fabrication, and low cost. Due to the special dense hot spot structure, the substrate reaches a SERS enhancement factor of 2.1 × 1011. Because of the excellent physical stability of polydimethylsiloxane, the substrate can be bent at will, and the SERS performance will not change with bending. This is very important to extract effective detection objects on complex surfaces. The substrate has good light transmittance and softness and can be directly attached to the detected agricultural products to realize real-time and rapid SERS monitoring. This structure exhibits extraordinary performance for thiram detection in the ultralow concentration range of 10-13 M.


Assuntos
Nanopartículas Metálicas , Tiram , Prata/química , Dióxido de Silício , Nanopartículas Metálicas/química , Análise Espectral Raman
6.
Opt Express ; 29(14): 21444-21457, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265932

RESUMO

Boosting nonlinear frequency conversions with plasmonic nanostructures at near-ultraviolet (UV) frequencies remains a great challenge in nano-optics. Here we experimentally design and fabricate a plasmon-enhanced second-harmonic generation (PESHG) platform suitable for near-UV frequencies by integrating aluminum materials with grating configurations involved in structural heterogeneity. The SHG emission on the proposed platform can be amplified by up to three orders of magnitude with respect to unpatterned systems. Furthermore, the mechanism governing this amplification is identified as the occurrence of quasi-Bragg plasmon modes near second-harmonic wavelengths, such that a well-defined coherent interplay can be attained within the hot spot region and facilitate the efficient out-coupling of local second-harmonic lights to the far-field. Our work sheds light into the understanding of the role of grating-coupled surface plasmon resonances played in PESHG processes, and should pave an avenue toward UV nanosource and nonlinear metasurface applications.

7.
Molecules ; 26(1)2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401666

RESUMO

Changing the morphology of noble metal nanoparticles and polarization dependence of nanoparticles with different morphologies is an important part of further research on surface plasma enhancement. Therefore, we used the method based on Matlab simulation to provide a simple and effective method for preparing the morphologies of Au nanoparticles with different morphologies, and prepared the structure of Au nanoparticles with good uniformity and different morphologies by oblique angle deposition (OAD) technology. The change of the surface morphology of nanoparticles from spherical to square to diamond can be effectively controlled by changing the deposition angle. The finite difference time domain (FDTD) method was used to simulate the electromagnetic fields of Au nanoparticles with different morphologies to explore the polarization dependence of nanoparticles with different shapes, which was in good agreement with Raman spectrum.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Anisotropia , Benzoatos/química , Campos Eletromagnéticos , Microscopia Eletrônica de Varredura , Poliestirenos/química , Compostos de Sulfidrila/química , Propriedades de Superfície
8.
Langmuir ; 35(27): 8921-8926, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31184904

RESUMO

Here, we develop a new method to improve the surface-enhanced Raman spectroscopy (SERS) activity of ZnO using Mg doping combined with noble metals. Highly aligned silver nanoparticles (AgNPs) decorated on an array of Mg-doped ZnO (MZO@Ag) were fabricated. Using rhodamine 6G as the probe molecule, SERS indicated that the MZO@Ag substrate possesses perfect sensitivity, homogeneity, and chemical stability. The enhancement mechanism of this substrate was analyzed in detail, and finite-difference time-domain (FDTD) simulations were used to examine "hot spot" distribution which generated gaps between the balls, the rods, and the stems. FDTD simulation calculated ( E/ E0)4 to be 2.5 × 106. Furthermore, the prepared substrates could degrade the target molecules in situ irradiated by visible light irradiation over the course of 40 min and then efficiently recover detectability through a recycling process. Our substrates were easy to fabricate, self-cleaning, and reusable. They are expected to provide new opportunities for the use of SERS in biological sensors, biomedical diagnostics, and food safety.

9.
Micromachines (Basel) ; 14(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37893248

RESUMO

Organized two-dimensional polystyrene bead arrays perform ion etching, and protruding nanostructures are created on polystyrene beads due to the shadow effects from the ring beads, leading to nucleus selection and growth in Au nanostructure deposition. Ag nanostructures are prepared via plasmon-mediated chemical reactions (PMCRs), leading to the Ag nanocavity geometry of the honeycomb pattern when the etching time and Ag growth time are tuned. Due to the strong electromagnetic coupling, the Ag honeycomb-shaped nanocavity array works as the SERS substrate with high sensitivity and good repeatability, which is used to detect thiram pesticide residues with a concentration down to 10-9 M.

10.
Nat Commun ; 14(1): 485, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717581

RESUMO

The gigahertz acoustic vibration of nano-optomechanical systems plays an indispensable role in all-optical manipulation of light, quantum control of mechanical modes, on-chip data processing, and optomechanical sensing. However, the high optical, thermal, and mechanical energy losses severely limit the development of nano-optomechanical metasurfaces. Here, we demonstrated a high-quality 5 GHz optoacoustic vibration and ultrafast optomechanical all-optical manipulation in a sub-5 nm tip-supported nano-optomechanical metasurface (TSNOMS). The physical rationale is that the design of the semi-suspended metasurface supported by nanotips of <5 nm enhances the optical energy input into the metasurface and closes the mechanical and thermal output loss channels, result in dramatically improvement of the optomechanical conversion efficiency and oscillation quality of the metasurface. The design strategy of a multichannel-loss-mitigating semi-suspended metasurface can be generalized to performance improvements of on-chip processed nano-optomechanical systems. Applications include all-optical operation of nanomechanical systems, reconfigurable nanophotonic devices, optomechanical sensing, and nonlinear and self-adaptive photonic functionalities.

11.
Medicine (Baltimore) ; 101(45): e31499, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36397356

RESUMO

Serum lactate dehydrogenase (LDH) has been identified as an independent risk factor for predicting all-cause mortality in patients with multiple diseases. However, the prognostic value of LDH levels in post-cardiac arrest patients remains uncertain. This study aimed to assess the association between LDH and mortality in intensive care unit (ICU) patients after cardiac arrest. This retrospective observational study is based on data from the Dryad Digital Repository, which included 374 consecutive adult patients after cardiac arrest. Patients were divided into 2 groups based on median LDH values. A multivariate Cox proportional hazards model was established to assess the independent relationship between LDH and ICU mortality. Cumulative mortality was compared using Kaplan-Meier curves. The cohort included 374 patients, of which 51.9% (194/374) died in the ICU. The overall death rate from cardiac arrest was significantly higher for patients with LDH ≥ 335 IU/L (59.6%) than for those with LDH < 335 IU/L (44.1%). In multiple Cox regression models, hazard ratios (HR) and corresponding 95% confidence intervals (CI) for logLDH and the 2 LDH groups were 1.72 (1.07, 2.78) and 1.42 (1.04, 1.93), respectively. Participants with LDH ≥ 335IU/L had a higher incidence of ICU mortality than LDH < 335 IU/L, as shown by the Kaplan-Meier curves (P = .0085). Subgroup analysis revealed that the association between LDH and ICU mortality was vitally stable, with all P interactions from different subgroups >.05. Serum LDH levels are positively associated with ICU mortality in patients after cardiac arrest, especially for patients with LDH ≥ 335 IU/L.


Assuntos
Parada Cardíaca , L-Lactato Desidrogenase , Adulto , Humanos , Estudos Retrospectivos , Prognóstico , Estudos de Coortes
12.
Artigo em Inglês | MEDLINE | ID: mdl-36305677

RESUMO

Based on etched PS sphere arrays, the different growths of Ag nanoparticles with tunable LSPR are designed when SiO2-25 nm/Ag-30 nm/SiO2-100 nm sandwich nanocavity structures are annealed at 500 °C, including the hexagonal silver nanoparticle rings, circular silver nanoparticle rings, and aggregated silver nanoparticles. The uniformity of particle size and regularity of position generate enhanced electromagnetic field and good surface-enhanced Raman spectroscopy signals as confirmed by UV-vis observation and finite difference time domain method simulation. The developed nanostructures are effectively used as stable, nonreproducible, and markable anti-counterfeiting signs.

13.
Exp Ther Med ; 17(4): 3174-3180, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30906481

RESUMO

The present study aimed to discover potential biomarkers for predicting the prognosis of acute respiratory distress syndrome (ARDS) in conjunction with lung ultrasound (LUS). Blood samples from 112 ARDS patients were collected to compare their partial oxygen pressure (PaO2)/fraction of inspired oxygen (FiO2), positive end-expiratory pressure (PEEP), lactic acid, sequential organ failure assessment (SOFA) score, clinical pulmonary infection score (CPIS) and APACHE II score. Kaplan-Meier plots and the log-rank test were performed to analyse the association between the platelet-activating factor acetylhydrolase (PAFAH) G994T polymorphism and the outcome of ARDS regarding mortality. A negative correlation between the LUS score and PaO2/FiO2, PEEP and lactic acid, as well as with the SOFA, CPIS and APACHE II score was confirmed with correlation coefficients of -0.493, -0.548, -0.642, -0.598, -0.566 and -0.567, respectively (all P<0.05). The activity of PAFAH and high-density lipoprotein-PAFAH in the serum collected from subjects of the GG genotype was similar to that in subjects of the GT genotype, but the low-density lipoprotein-PAFAH activity in the serum collected from GG subjects was significantly higher than that in GT subjects. An evident reduction in the PEEP, level of lactic acid, as well as the SOFA, CPIS and APACHE II score was observed in GG subjects, accompanied by a significantly increased PaO2/FiO2. Kaplan-Meier analysis indicated that subjects with a high LUS score had a significantly higher survival rate than those with a low LUS score, and the mortality risk for GG subjects was significantly lower than that for GT subjects. Finally, among all groups (genotype and LUS groups), GG subjects with a high LUS score had the lowest mortality risk, whereas GT subjects with a low LUS score had the highest mortality risk. In addition, the survival rate of GT subjects with a high LUS score was higher than that of GG subjects with a low LUS score. In conclusion, the combination of the LUS score and the G994T polymorphism in exon 9 of the PAFAH gene may be used as a potential prognostic marker for ARDS.

14.
Nanoscale ; 11(14): 6576-6583, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30644964

RESUMO

Hexagonal Ag nanoparticle arrays are exclusively grown on top of the interstices of Au nanobowl arrays. The photoinduced effect of the enhanced electromagnetic field between Au nanobowls accelerated the chemical reaction and is responsible for Ag growth in defined local positions. The enhanced electric field of the Au nanobowl array induced a photoreaction, which resulted in Ag growth in the hot area. Interestingly, the sizes and positions of the Ag nanoparticles distributed in the strong electric field of the Au nanobowl array are easily controlled. A six-axis symmetric pattern of Ag nanoparticle growth is realized based on the use of vertically incident circularly polarized light. Furthermore, a three-axis symmetric nanoperiodic structure is obtained through the use of linearly polarized oblique waves with specific incidence angles. This research shows that an electric field can be used to control a chemical reaction at the nanometer level, enabling the control and design of a wide variety of nanoperiodic structures.

15.
Nanomaterials (Basel) ; 9(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683724

RESUMO

Controlling chemical reactions by plasma is expected to be a new method for improving the structural properties of substrates. An Au nanojar array was prepared when Au was deposited onto a 2D polystyrene (PS) array. The site-selective chemical growth of Ag nanoparticle rings was realized around the Au nanojar necks by a local surface plasmon resonance (LSPR)-assisted chemical reaction. The catalytic hotspots in the nanostructure array could be controlled by both etching the nanojars and Au or TiO2 sputtering onto the nanojars, which were confirmed by the growth sites of the Ag nanoparticle in the LSPR-assisted chemical reaction. The structure of the nanojars and the electric field distributions of the growing nanoparticles were simulated and analyzed using Finite-Difference Time-Domain. FDTD simulations showed that the changes in the nanojar shape led to the changed hotspot distributions. At the same time, tracking the hotspot shifts in the process of structural change was also achieved by the observation of Ag growth. Nanoarray structure prepared by LSPR-assisted chemical reaction is one of the hot fields in current research and is also of great significance for the application of Surface-Enhanced Raman Scattering.

16.
Nanomaterials (Basel) ; 8(7)2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976862

RESUMO

Ag⁻SiO2 nanomace arrays were prepared on a two-dimensional ordered colloidal (2D) polystyrene sphere template by co-sputtering Ag and SiO2 in a magnetron sputtering system. The lateral size of the nanomaces and the distance between the neighbor nanomaces were controlled by adjusting the etching time of the 2D template. The nanomaces were composed of SiO2-isolated Ag nanoparticles, which produced surface-enhanced Raman scattering (SERS) enhancement, and 3D hot spots were created between the neighbor nanomaces. When the distance between the nanomaces was sufficiently large, triangle-shaped nanostructures on silicon substrate were observed, which also contributed to the enhancement of the SERS signals. The finite-difference time-domain (FDTD) method was used to calculate the electromagnetic field distributions in the Ag⁻SiO2 nanomace arrays, which generated physical reasons for the change of the SERS signals.

17.
Nanomaterials (Basel) ; 8(6)2018 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-29914218

RESUMO

Emerging opportunities based on two-dimensional (2D) layered structures can utilize a variety of complex geometric architectures. Herein, we report the synthesis and properties of a 2D+0D unique ternary platform-core-shell nanostructure, termed Ag@Cu2O-rGO, where the reduced graphene oxide (rGO) 2D acting as a platform is uniformly decorated by Ag@Cu2O core-shell nanoparticles. Cu2O nanoparticles occupy the defect positions on the surface of the rGO platform and restore the conjugation of the rGO structure, which contributes to the significant decrease of the ID/IG intensity ratio. The rGO platform can not only bridge the isolated nanoparticles together but also can quickly transfer the free electrons arising from the Ag core to the Cu2O shell to improve the utilization efficiency of photogenerated electrons, as is verified by high efficient photocatalytic activity of Methyl Orange (MO). The multi-interface coupling of the Ag@Cu2O-rGO platform-core-shell nanostructure leads to the decrease of the bandgap with an increase of the Cu2O shell thickness, which broadens the absorption range of the visible light spectrum.

18.
Nanoscale ; 10(17): 8106-8114, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29671449

RESUMO

Hexagonal close-packed tilted Ag nanorod arrays that exhibit excellent uniformity and reproducibility were prepared. The tilt angle was easily controlled by regulating the sputtering angle, accompanied by a reduction and constancy in the gap size of adjacent nanorods, which is 30° and 90° relative to the sputtering direction. The surface enhanced Raman spectroscopy (SERS) technique was used to characterize the interaction of tilted Ag nanorod arrays with polarized laser excitation. Interestingly, the SERS polarization-dependence increased with increasing tilt angle of the Ag nanorods. To elucidate the essential factors responsible for this SERS result, three-dimensional (3D) electromagnetic enhancement distribution for the proposed system was numerically simulated based on p- and s-polarization excitation. Most importantly, the fundamental reasons for the polarization dependence of SERS were obtained by a quantitative 3D numerical simulation of hotspot distribution for adjacent nanorods.

19.
J Phys Chem Lett ; 9(20): 6047-6051, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30188128

RESUMO

We discuss how the controllable carrier influences the localized surface plasmon resonance (LSPR) and charge transfer (CT) in the same system based on ultraviolet-visible and surface-enhanced Raman scattering (SERS) measurements. The LSPR can be easily tuned from 580 to 743 nm by changing the sputtering power of Cu2S in the Ag and Cu2S composite substrate. During this process, surprisingly, we find that the LSPR is proportional to the sputtering power of Cu2S. This observation indicates that LSPR can be accurately adjusted by changing the content of the semiconductor, or even the carrier density. Moreover, we characterize the carrier density through the detection of the Hall effect to analyze the Raman shift caused by CT and obtain the relationships between them. These fundamental discussions provide a guideline for tunable LSPR and the investigation of CT.

20.
J Nippon Med Sch ; 82(5): 257-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26568394

RESUMO

INTRODUCTION: Aconitine is a highly toxic diterpenoid alkaloid, produced by plants of the Aconitum genus, that is still used in Chinese herbal medicines. Aconitine poisoning remains common in China and other parts of Asia. CASE REPORT: A 48-year-old man received a diagnosis of aconitine poisoning after ingesting herbal medicinal wine made with caowu, which is made from Aconitum kusnezoffii roots, and was admitted to our hospital' s emergency department. Electrocardiography and thoracoabdominal computed tomography showed cardiovascular toxicity from aconitine poisoning along with polycystic renal hemorrhaging. Because the arrhythmia was not controlled with lidocaine, blood purification with a reduced dosage of heparin was performed to treat the arrhythmia and to avoid increasing the bleeding of the polycystic renal hemorrhage. The patient recovered from aconitine poisoning and polycystic kidney hemorrhage. CONCLUSIONS: This case significantly advances our understanding of hemoperfusion with reduced heparin for the treatment of ventricular arrhythmia caused by aconitine poisoning.


Assuntos
Aconitina/intoxicação , Hemorragia/complicações , Doenças Renais Policísticas/complicações , Eletrocardiografia , Medicina Herbária , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação/complicações , Intoxicação/fisiopatologia , Intoxicação/terapia , Tomografia Computadorizada por Raios X
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