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1.
Front Microbiol ; 15: 1351784, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298891

RESUMO

Helicobacter pylori (H. pylori) infection may alter the host's resistance to tsutsugamushi disease pathogens through the Th1 immune response, leading to potential synergistic pathogenic effects. A total of 117 scrub typhus cases at Beihai People's Hospital and affiliated hospitals of Youjiang University for Nationalities and Medical Sciences were studied from January to December 2022, alongside 130 healthy individuals forming the control group. All participants underwent serum H. pylori antibody testing. The prevalence of H. pylori infection was significantly higher among scrub typhus patients (89.7%) compared to healthy individuals (54.6%) (p < 0.05). Moreover, type I H. pylori infection was notably more prevalent in scrub typhus cases (67.5%) compared to healthy individuals (30%) (p < 0.05). Multifactorial analysis demonstrated type I H. pylori infection as an independent risk factor for scrub typhus (adjusted odds ratio: 2.407, 95% confidence interval: 1.249-4.64, p = 0.009). Among scrub typhus patients with multiple organ damage, the prevalence of type I H. pylori infection was significantly higher (50.6%) than type II H. pylori infection (15.4%) (χ2 = 4.735, p = 0.030). These results highlight a higher incidence of H. pylori infection in scrub typhus patients compared to the healthy population. Additionally, type I H. pylori strain emerged as an independent risk factor for scrub typhus development. Moreover, individuals infected with type I H. pylori are more susceptible to multiple organ damage. These findings suggest a potential role of H. pylori carrying the CagA gene in promoting and exacerbating scrub typhus.

2.
Chem Commun (Camb) ; 60(4): 420-423, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38086642

RESUMO

We synthesized a small molecule, DBPTO, and used it as a cathode material in aqueous zinc-ion batteries. DBPTO presented a high reversible capacity of 382 mA h g-1 at 0.05 A g-1 and a long lifespan of over 60 000 cycles. In the same π-conjugated skeleton, DBPTO (containing four CO and two CN groups) shows a narrower energy gap than TAPQ (containing CO and four CN groups), which leads to the superior rate and cycling performance of DBPTO. The mechanism of charge storage of DBPTO also revealed that H+ and Zn2+ coordinated with the CO and CN sites by ex situ structural characterization and DFT calculations. Our results provide new insights into the design of organic cathodes with a high rate capability and long lifespan. Further efforts will focus on a deeper understanding of the charge storage mechanism.

3.
Nanoscale ; 15(42): 17036-17044, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37846513

RESUMO

The electronic contact between two-dimensional (2D) transition metal dichalcogenide (TMD) semiconductors and metal electrodes is a formidable challenge due to the undesired Schottky barrier, which severely limits the electrical performance of TMD devices and impedes the exploration of their unconventional physical properties and potential electronic applications. In this study, we report a two-step chemical vapor deposition (CVD) growth of 2D TaSe2-WSe2 metal-semiconductor heterostructures. Raman mapping confirms the precise spatial modulation of the as-grown 2D TaSe2-WSe2 heterostructures. Transmission electron microscopy (TEM) characterization reveals that this two-step method provides a high-quality and clean interface of the 2D TaSe2-WSe2 heterostructures. Meanwhile, the upper 1T-TaSe2 is formed heteroepitaxially on/around the pre-synthesized 2H-WSe2 monolayers, exhibiting an epitaxial relationship of (20-20)TaSe2//(20-20)WSe2 and [0001]TaSe2//[0001]WSe2. Furthermore, characterization studies using a Kelvin probe force microscope (KPFM) and electrical transport measurements present compelling evidence that the 2D metal-semiconductor heterostructures under investigation can improve the performance of electrical devices. These results bear substantial significance in augmenting the properties of field-effect transistors (FETs), leading to notable improvements in FET mobility and on/off ratio. Our study not only broadens the horizons of direct growth of high-quality 2D metal-semiconductor heterostructures but also sheds light on potential applications in future high-performance integrated circuits.

4.
Small ; 19(44): e2302365, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37420328

RESUMO

As representative extended planar defects, crystallographic shear (CS) planes, namely Wadsley defects, play an important role in modifying the physical and chemical properties of metal oxides. Although these special structures have been intensively investigated for high-rate anode materials and catalysts, it is still experimentally unclear how the CS planes form and propagate at the atomic scale. Here, the CS plane evolution in monoclinic WO3 is directly imaged via in situ scanning transmission electron microscope. It is found that the CS planes nucleate preferentially at the edge step defects and proceed by the cooperative migration of WO6 octahedrons along particular crystallographic orientations, passing through a series of intermediate states. The local reconstruction of atomic columns tends to form (102) CS planes featured with four edge-sharing octahedrons in preference to the (103) planes, which matches well with the theoretical calculations. Associated with the structure evolution, the sample undergoes a semiconductor-to-metal transition. In addition, the controlled growth of CS planes and V-shaped CS structures can be achieved by artificial defects for the first time. These findings enable an atomic-scale understanding of CS structure evolution dynamics.

5.
J Int Med Res ; 51(6): 3000605231183702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389592

RESUMO

Elemental mercury impaction in the appendix can cause subsequent local and systemic complications. We present a case of a teenage boy who ingested approximately 10 mL of elemental mercury, resulting in residual mercury sequestration in the appendix after conservative management. We performed laparoscopic appendectomy to remove the residual mercury. The patient made a complete clinical recovery without adverse events related to mercury poisoning over the 6-month follow-up. We highlight the advantages of laparoscopic appendectomy, abdominal computed tomography (CT), negative pressure operating rooms, and surgeon protection to improve surgical success rates. This case report adds to the literature on the management of elemental mercury impaction in the appendix and provides valuable insights for clinical decision-making.


Assuntos
Apêndice , Laparoscopia , Mercúrio , Masculino , Adolescente , Humanos , Apendicectomia , Apêndice/diagnóstico por imagem , Apêndice/cirurgia , Tomada de Decisão Clínica
6.
Org Lett ; 24(24): 4485-4489, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35678627

RESUMO

We present an efficient and versatile visible light-driven methodology for synthesizing sulfinamides and sulfoxides using nitroarenes as the nitrogen source and thiophenols as the sulfur source. The switch-over of the two reaction pathways was achieved by changing the type of photocatalyst and the amount of thiophenol in the reaction mixture. The reaction proceeds under mild conditions with good functional group tolerance and can easily be scaled up.

7.
Nanoscale ; 14(20): 7579-7588, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35506868

RESUMO

Synthesis of high-quality ZnO/ZnS heterostructures with tunable phase and controlled structures is in high demand due to their adjustable band gap and efficient electron-hole pair separation. In this report, for the first time, remote heteroepitaxy of single-crystalline ZnO/ZnS core/shell nanowire arrays has been realized using amorphous HfO2 as the buffer layer. Zinc blende or wurtzite ZnS epilayer can be efficiently fabricated under the same thermal deposition condition by adjusting the buffer layer thickness, even among the same batch of products, respectively. Structural characterization reveals "(01-10)ZnOwz//(2-20)ZnSZB, [0001]ZnOWZ//[001]ZnSZB" and "(01-10)ZnOWZ//(01-10)ZnSWZ, [0002]ZnOWZ//[0002]ZnSWZ" epitaxial relationships between the core and the shell, respectively. The cathodoluminescence measurement demonstrates that the tuning of the optical properties can be accomplished by preparing a heterostructure with HfO2, in which a strong green emission increases at the expense of the quenching of UV emission. In addition, the core/shell heterostructure based Schottky diode exhibits an asymmetrical rectifying behavior and an outstanding photo-electronic switching-effect. We believe that the aforementioned results could provide fundamental insights for epitaxial growth of structure-tunable ZnO/ZnS heterostructures on the nanoscale. Furthermore, this promising route buffered by the high-k material can broaden the options for fabricating heterojunctions and promote their application in photoelectric nanodevices.

8.
Chem Commun (Camb) ; 57(35): 4307-4310, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913965

RESUMO

A rocking-chair aqueous proton battery is assembled by using dipyridophenazine and indium hexacyanoferrate as the anode and cathode materials, respectively. The reversible amination of redox-active phenazine moieties in dipyridophenazine and fast intercalation-deintercalation of protons in hexacyanoferrate enable the aqueous proton battery to achieve a reversible specific capacity of 37 mA h g-1 at 1 A g-1, good cycling stability with 76.1% capacity retention over 3000 cycles and excellent rate capability.

9.
RSC Adv ; 10(37): 21839-21844, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35516610

RESUMO

Water-soluble 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) derivatives have been frequently utilized as catholytes for aqueous redox flow batteries to achieve cost-effective renewable energy storage. However, fundamental knowledge of TEMPO derivatives is still largely underdeveloped. Herein, a comprehensive study on the properties of TEMPO derivatives has been conducted in aqueous electrolytes. The results confirm that the redox potential, diffusion coefficient, electron transfer rate constant and solubility are clearly influenced by functional groups of TEMPO derivatives and supporting electrolytes. The charge-discharge cycling performance is evaluated using a symmetric redox flow battery configuration. The capacity decay for TEMPO-based catholytes is mainly derived from the crossover of the oxidized state. The presented study not only advances an in-depth understanding of TEMPO-based RFB applications, but also highlights the challenge of crossover of redox-active TEMPO derivative molecules applied in aqueous RFBs.

10.
Dalton Trans ; 46(10): 3276-3283, 2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28224147

RESUMO

Core-shell nanostructured hollow carbon nanospheres@nickel cobalt double hydroxides (HCNs@NiCo-LDH) were fabricated using a facile hydrothermal method and investigated as high-performance electrode materials for supercapacitors. HCNs were acquired by a successive polymerization, carbonization and etching process, which was subsequently wrapped by ultrathin NiCo-LDH nanosheets. The HCNs@NiCo-LDH electrode achieved a high specific capacitance (2558 F g-1 at 1 A g-1) and outstanding rate capability with 74.9% capacitance retention after a 20-fold increase in current density. Capacitances of 2405, 2310, 2168, 2006 and 1916 F g-1 can be achieved at rates of 3, 5, 10, 15 and 20 A g-1, respectively, which are much higher than the specific capacitances of most reported carbon loaded NiCo-LDH. Specifically, the assembled HCNs@NiCo-LDH//graphene asymmetric supercapacitor displayed distinguished capacitive behaviors with a prominent specific capacitance of 172.8 F g-1 and eminent cycling stability with 93.5% capacitance retention after 3000 cycles. These remarkable electrochemical properties indicate that the unique HCNs@NiCo-LDH core-shell electrode is highly promising for application in energy storage fields.

11.
Small ; 12(19): 2549-53, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27007303

RESUMO

Pyrolyzing Fe- and N-contained precursor together or separately with graphene results in codoped graphene dominated by bonded or separated Fe and N configuration, respectively. While the FeN bonded case greatly enhances activity toward oxygen reduction, the separated one does not. This rationally designed Fe and N codoped 3D graphene exhibits superior electrocatalytic activity than the state-of-the-art Pt/C catalyst.

12.
Dalton Trans ; 42(36): 12926-33, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23719649

RESUMO

The thermally induced de-/rehydrogenation performance of the graphene supported Pt nanoparticles (Pt/G) doped LiBH4 was greatly improved even at very low catalyst content due to a synergetic effect of Pt addition and nanoconfinement in graphene. For the 5 wt% Pt/G doped LiBH4 sample, the onset hydrogen desorption temperature is about 140 °C lower than that of the pure LiBH4. With increasing loading of the Pt/G catalysts in LiBH4 samples, the onset dehydrogenation temperature and the two main desorption peaks from LiBH4 were found to decrease while the hydrogen release amount increased. About 17.8 wt% can be released from the 50 wt% Pt/G doped LiBH4 sample below 500 °C. Moreover, variation of the equilibrium pressure (350-450 °C) indicates that the dehydrogenation enthalpy is reduced from 74 kJ mol(-1) H2 for the pure LiBH4 to ca. 48 kJ mol(-1) H2 for the 10 wt% Pt/G doped LiBH4, showing improved thermodynamic properties. More importantly, a reversible capacity of ca. 8.1 wt% in the 30th de-/rehydrogenation cycle was achieved under 3 MPa H2 at 400 °C for 10 h, indicating that the Pt/G catalysts play a crucial role in the improvement of the hydrogen uptake reversibility of LiBH4 at lower temperature and pressure conditions. Especially, LiBH4 was reformed and a new product, Li2B10H10, was detected after the rehydrogenation process.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 233-6, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23586263

RESUMO

For the digital X-ray fluorescence analyzer, the voltage of the instability baseline will directly affect the performance of the instrument, resulting in decreased energy resolution. In order to solve this problem, Kalman filtering algorithm was used for pulse signal baseline estimate in the digital X-ray fluorescence. Whether using the classic Kalman filter, or the simplified sage-husa, or the improved sage-husa, their baseline filtering effects were all poor. So, it is necessary to improve and optimize existing algorithms. The method of Double-Forgotten was put forward to establish a new model of adaptive Kalman filter algorithm based on the sage-husa. The experiment results show that a very good filtering effect was obtained using the mathematical model of the baseline filter. The algorithm solved the problem of filtering divergence, avoided slow convergence of baseline and realized the pulse baseline restoration, and improved the instrumental energy resolution.

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