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1.
Front Pharmacol ; 12: 573145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995002

RESUMO

Objective: Harmonizing formulas are associated with beneficial renal outcomes in chronic kidney disease (CKD), but the therapeutic mechanisms are unclear. The study aims to explore the associations of intentions and independent factors with harmonizing formulas prescriptions for patients with CKD. Methods: We conducted a population-based cross-sectional study to explore factors associated with harmonizing formulas prescription. Patients who had been prescribed harmonizing formulas after CKD diagnosis was defined as the using harmonizing formulas group. Disease diagnoses when having harmonizing formula prescriptions and patient characteristics related to these prescriptions were collected. Results: In total, 24,971 patients were enrolled in this analysis, and 5,237 (21%) patients were prescribed harmonizing formulas after CKD diagnosis. The three most frequent systematic diseases and related health problems for which harmonizing formula prescriptions were issued in CKD were symptoms, signs, and ill-defined conditions (24.5%), diseases of the digestive system (20.67%), and diseases of the musculoskeletal system (12.9%). Higher likelihoods of harmonizing formula prescriptions were associated with young age (adjusted odds ratio: 0.98, 95% confidence interval: 0.97-0.98), female sex (1.79, 1.68-1.91), no diabetes (1.20, 1.06-1.36), no hypertension (1.38, 1.27-1.50), no cerebrovascular disease (1.34, 1.14-1.56), less disease severity (0.85, 0.83-0.88), using nonsteroidal anti-inflammatory drugs (NSAIDs) (1.65, 1.54-1.78), and using analgesic drugs other than NSAIDs (1.47, 1.35-1.59). Conclusion: Harmonizing formulas are commonly used for treating symptoms of the digestive and musculoskeletal systems in CKD cases. Further research on harmonizing formula effectiveness with regard to particular characteristics of CKD patients is warranted.

2.
Opt Lett ; 46(4): 864-867, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33577533

RESUMO

In this Letter, we demonstrate mid-infrared (MIR) lateral p-i-n GeSn waveguide photodetectors (WGPDs) on silicon, to the best of our knowledge for the first time, as a key enabler of MIR electronic-photonic integrated circuits (EPICs). Narrow-bandgap GeSn alloys were employed as the active material to enable efficient photodetection in the MIR region. A lateral p-i-n homojunction diode was designed and fabricated to significantly enhance the optical confinement factor of the guided modes and thus enhance the optical responsivity. Thus, a photodetection range of up to 1950 nm and a good responsivity of 0.292 A/W at 1800 nm were achieved. These results demonstrate the feasibility of planar GeSn WGPDs for monolithic MIR EPICs on silicon.

3.
Opt Lett ; 45(24): 6683-6686, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325870

RESUMO

We report high-performance lateral p-i-n Ge waveguide photodetectors (WGPDs) on a Ge-on-insulator (GOI) platform that could be integrated with electronic-photonic integrated circuits (EPICs) for communication applications. The high-quality Ge layer affords a low absolute dark current. A tensile strain of 0.144% in the Ge active layers narrows the direct bandgap to enable efficient photodetection over the entire range of C- and L-bands. The low-index insulator layer enhances optical confinement, resulting in a good optical responsivity. These results demonstrate the feasibility of planar Ge WGPDs for monolithic GOI-based EPICs.

4.
Micromachines (Basel) ; 11(9)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32839407

RESUMO

Metal-semiconductor-metal photodetectors (MSM PDs) are effective for monolithic integration with other optical components of the photonic circuits because of the planar fabrication technique. In this article, we present the design, growth, and characterization of GeSn MSM PDs that are suitable for photonic integrated circuits. The introduction of 4% Sn in the GeSn active region also reduces the direct bandgap and shows a redshift in the optical responsivity spectra, which can extend up to 1800 nm wavelength, which means it can cover the entire telecommunication bands. The spectral responsivity increases with an increase in bias voltage caused by the high electric field, which enhances the carrier generation rate and the carrier collection efficiency. Therefore, the GeSn MSM PDs can be a suitable device for a wide range of short-wave infrared (SWIR) applications.

5.
Opt Express ; 28(16): 23739-23747, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32752366

RESUMO

The germanium-on-insulator (GOI) has recently emerged as a new platform for complementary metal-oxide-semiconductor (CMOS)-compatible photonic integrated circuits. Here we report on resonant-cavity-enhanced optical responses in Ge photodetectors on a GOI platform where conventional photodetection is difficult. A 0.16% tensile strain is introduced to the high-quality Ge active layer to extend the photodetection range to cover the entire range of telecommunication C- and L-bands (1530-1620 nm). A carefully designed vertical cavity is created utilizing the insulator layer and the deposited SiO2 layer to enhance the optical confinement and thus optical response near the direct-gap absorption edge. Experimental results show a responsivity peak at 1590 nm, confirming the resonant cavity effect. Theoretical analysis shows that the optical responsivity in the C- and L-bands is significantly enhanced. Thus, we have demonstrated a new type of Ge photodetector on a GOI platform for CMOS-compatible photonic integrated circuits for telecommunication applications.

6.
Opt Lett ; 45(6): 1463-1466, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32163992

RESUMO

The 2 µm wavelength band has recently gained increased attention for potential applications in next-generation optical communication. However, it is still challenging to achieve effective photodetection in the 2 µm wavelength band using group-IV-based semiconductors. Here we present an investigation of GeSn resonant-cavity-enhanced photodetectors (RCEPDs) on silicon-on-insulator substrates for efficient photodetection in the 2 µm wavelength band. Narrow-bandgap GeSn alloys are used as the active layer to extend the photodetection range to cover the 2 µm wavelength band, and the optical responsivity is significantly enhanced by the resonant cavity effect as compared to a reference GeSn photodetector. Temperature-dependent experiments demonstrate that the GeSn RCEPDs can have a wider photodetection range and higher responsivity in the 2 µm wavelength band at higher temperatures because of the bandgap shrinkage. These results suggest that our GeSn RCEPDs are promising for complementary metal-oxide-semiconductor-compatible, efficient, uncooled optical receivers in the 2 µm wavelength band for a wide range of applications.

7.
Chem Asian J ; 12(12): 1314-1325, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28332343

RESUMO

Bifunctional SBA-1 mesoporous silica nanoparticles (MSNs) with carboxylic acid and amino groups (denoted as CNS-10-10) have been successfully synthesized, characterized, and employed as adsorbents for dye removal. Adsorbent CNS-10-10 shows high affinity towards cationic and anionic dyes in a wide pH range, and exhibits selective dye removal of a two-dye mixture system of cationic methylene blue and anionic eosin Y. By changing the pH of the medium, the selectivity of the adsorption behavior can be easily modulated. For comparison purposes, the counterparts, that is, pure silica SBA-1 MSNs (CS-0) and those with either carboxylic acid or amino functional groups (denoted as CS-10 and NS-10, respectively) were also prepared to evaluate their dye-adsorption behaviors. As revealed by the zeta-potential measurements, the electrostatic interaction between the adsorbent surface and the dye molecule plays an important role in the adsorption mechanism. Adsorbent CNS-10-10 can be easily regenerated and reused, and maintains its adsorption efficiency up to 80 % after four cycles.

8.
J Hazard Mater ; 309: 236-48, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26906434

RESUMO

In this work, we demonstrate that a high density of −COOH groups loading, up to 60 mol% based on silica, is successfully incorporated into SBA-16 via a one-pot synthesis route, which involves co-condensation of carboxyethylsilanetriol sodium salt (CES) and tetraethylorthosilicate (TEOS) templated by Pluronic F127 and P123 in an acidic medium. A variety of characterization techniques are performed to confirm quantitative incorporation of carboxylic groups into ordered cubic mesostructures. These functionalized materials are used to effectively remove two cationic dyes methylene blue (MB) and phenosafranine (PF) with the maximum adsorption capacities of 561 and 519 mg g(-1), respectively, at pH 9. The zeta potential results reveal that the electrostatic interactions between cationic dye molecule and negatively charged surface of the adsorbent play a crucial role in their high adsorption capacities. For a binary component system consisting of MB and PF, competitive adsorption of these two dyes is observed with adsorption capacity values slightly lower than those of the corresponding single dye systems. The dye adsorbed material can be easily regenerated by simple acid washing and be reused for five times with MB removal efficiency still up to 98.6%, showing its great potentials in environmental remediation.

9.
J Org Chem ; 78(19): 9738-47, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24006927

RESUMO

A mild and efficient stereoselective synthesis of hexacyclic indole alkaloids with a tetrahydro-ß-carboline motif has been developed by utilizing the Pictet-Spengler reaction and tandem N-acylation followed by intramolecular Diels-Alder cyclization. Initially, a diene unit was installed in the tetrahedron ß-carboline skeleton through Pictet-Spengler cyclization of the corresponding aldehyde with tryptophan ester. The dienophile moiety was introduced by N-acylation of tetrahydro-ß-carboline. Successive, in situ, [4 + 2] intramolecular Diels-Alder cycloaddition of the activated dienophile and conjugated diene containing intermediate furnished bridged polycyclic heterocycles with high diastereoselectivity. Formation of four new rings, five new covalent bonds, and five new chiral centers with excellent stereoselectivity is the key feature of this strategy. The diastereoselective formation of product was attributed to intramolecular chirality transfer through a chiral amino acid. The stereoselective outcome of this tandem reaction was confirmed by X-ray crystallographic studies. The developed synthetic strategy was also explored on a soluble polymer support to incorporate the advantage of rapid synthesis and a high-throughput workup process toward the development of a green synthetic protocol for polycyclic alkaloids.


Assuntos
Alcaloides/síntese química , Compostos Heterocíclicos de Anel em Ponte/síntese química , Compostos Policíclicos/síntese química , Acilação , Alcaloides/química , Cristalografia por Raios X , Reação de Cicloadição , Compostos Heterocíclicos de Anel em Ponte/química , Estrutura Molecular , Compostos Policíclicos/química , Estereoisomerismo
10.
Nanoscale ; 5(13): 5863-71, 2013 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-23695448

RESUMO

We herein report on the preparation of epoxy nanocomposites, which had enhanced thermal conductivities but were still electrical insulators, incorporating hybrid nanosheets (NSs) with sandwich structures composed of thermally reduced graphene oxide (TRGO) and silica. The silica layer covered the surface of the TRGO, hindering electrical conduction and effectively forming a 3D phonon transport channel that had a unique effect on the electrical and thermal properties of the epoxy matrix. A 1 wt% TRGO-silica NS epoxy nanocomposite maintained an electrical resistivity of 2.96 × 10(11)Ω cm, and its thermal conductivity was 0.322 W m(-1) K(-1), which is 61% higher than the conductivity of an epoxy nanocomposite without TRGO-silica NSs (0.2 W m(-1) K(-1)).

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