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1.
Opt Express ; 31(19): 30495-30504, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710590

RESUMO

We have designed a metal-semiconductor-metal (MSM) solar-blind ultraviolet (UV) photodetector (PD) by utilizing Al0.55Ga0.45N/Al0.4Ga0.6N/Al0.65Ga0.35N heterostructures. The interdigital Ni/Au metal stack is deposited on the Al0.55Ga0.45N layer to form Schottky contacts. The AlGaN hetero-epilayers with varying Al content contribute to the formation of a two-dimensional electron gas (2DEG) conduction channel and the enhancement of the built-in electric field in the Al0.4Ga0.6N absorption layer. This strong electric field facilitates the efficient separation of photogenerated electron-hole pairs. Consequently, the fabricated PD exhibits an ultra-low dark current of 1.6 × 10-11 A and a broad spectral response ranging from 220 to 280 nm, with a peak responsivity of 14.08 A/W at -20 V. Besides, the PD demonstrates an ultrahigh detectivity of 2.28 × 1013 Jones at -5 V. Furthermore, to investigate the underlying physical mechanism of the designed solar-blind UV PD, we have conducted comprehensive two-dimensional device simulations.

2.
Inorg Chem ; 56(12): 7145-7150, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28581288

RESUMO

A novel pillar-layer porous lanthanide metal-organic framework [Tb3(ODA)3(BPDC)3Na2]n·Gx (UTSA-222, G = guest molecules) was constructed from an organic ligand [1,1'-biphenyl]-4,4'-dicarboxylate (BPDC2-) and a lanthanide metalloligand [Tb(ODA)]+ (H2ODA = oxydiacetic acid). The UTSA-222 contains two-dimensional intersecting channels with the Brunauer-Emmett-Teller surface area and pore volume of 703 m2 g-1 and 0.344 cm3 g-1, respectively, for the activated sample. It shows moderately high adsorption selectivity for C2H2/CO2 and C2H2/CH4 separations at 1 atm and room temperature.

3.
ACS Appl Mater Interfaces ; 16(21): 27813-27820, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38603540

RESUMO

Solar-blind photodetectors based on wide bandgap semiconductors have recently attracted a lot of interest. Nickel-containing spinel phase oxides, such as NiAl2O4, are stable p-type semiconductors. This paper describes a multifunctional solar-blind photodetector based on a NiAl2O4/4H-SiC heterojunction that utilizes photovoltaic effects. The position sensitivity reaches a value of 1589.7 mV/mm under 405 nm laser illumination, while the relaxation times of vertical photovoltaic (VPV) effect and lateral photovoltaic (LPV) effect under 266 nm laser illumination are only 0.32 and 0.42 µs, respectively. This junction was used to create a space optical communication system with sunlight having little effect on its optoelectronic properties. The ultrafast photovoltaic relaxation time makes NiAl2O4/4H-SiC a promising candidate for self-powered high-performance solar-blind detectors.

4.
MedComm (2020) ; 5(2): e476, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38405060

RESUMO

Cholesterol homeostasis is crucial for cellular and systemic function. The disorder of cholesterol metabolism not only accelerates the onset of cardiovascular disease (CVD) but is also the fundamental cause of other ailments. The regulation of cholesterol metabolism in the human is an extremely complex process. Due to the dynamic balance between cholesterol synthesis, intake, efflux and storage, cholesterol metabolism generally remains secure. Disruption of any of these links is likely to have adverse effects on the body. At present, increasing evidence suggests that abnormal cholesterol metabolism is closely related to various systemic diseases. However, the exact mechanism by which cholesterol metabolism contributes to disease pathogenesis remains unclear, and there are still unknown factors. In this review, we outline the metabolic process of cholesterol in the human body, especially reverse cholesterol transport (RCT). Then, we discuss separately the impact of abnormal cholesterol metabolism on common diseases and potential therapeutic targets for each disease, including CVD, tumors, neurological diseases, and immune system diseases. At the end of this review, we focus on the effect of cholesterol metabolism on eye diseases. In short, we hope to provide more new ideas for the pathogenesis and treatment of diseases from the perspective of cholesterol.

5.
Front Genet ; 15: 1385293, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818040

RESUMO

Background: Varicose veins (VV) are a common chronic venous disease that is influenced by multiple factors. It affects the quality of life of patients and imposes a huge economic burden on the healthcare system. This study aimed to use integrated analysis methods, including Mendelian randomization analysis, to identify potential pathogenic genes and drug targets for VV treatment. Methods: This study conducted Summary-data-based Mendelian Randomization (SMR) analysis and colocalization analysis on data collected from genome-wide association studies and cis-expression quantitative trait loci databases. Only genes with PP.H4 > 0.7 in colocalization were chosen from the significant SMR results. After the above analysis, we screened 12 genes and performed Mendelian Randomization (MR) analysis on them. After sensitivity analysis, we identified four genes with potential causal relationships with VV. Finally, we used transcriptome-wide association studies and The Drug-Gene Interaction Database data to identify and screen the remaining genes and identified four drug targets for the treatment of VV. Results: We identified four genes significantly associated with VV, namely, KRTAP5-AS1 [Odds ratio (OR) = 1.08, 95% Confidence interval (CI): 1.05-1.11, p = 1.42e-10] and PLEKHA5 (OR = 1.13, 95% CI: 1.06-1.20, p = 6.90e-5), CBWD1 (OR = 1.05, 95% CI: 1.01-1.11, p = 1.42e-2) and CRIM1 (OR = 0.87, 95% CI: 0.81-0.95, p = 3.67e-3). Increased expression of three genes, namely, KRTAP5-AS1, PLEKHA5, and CBWD1, was associated with increased risk of the disease, and increased expression of CRIM1 was associated with decreased risk of the disease. These four genes could be targeted for VV therapy. Conclusion: We identified four potential causal proteins for varicose veins with MR. A comprehensive analysis indicated that KRTAP5-AS1, PLEKHA5, CBWD1, and CRIM1 might be potential drug targets for varicose veins.

6.
Nanoscale Adv ; 6(12): 3073-3081, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38868825

RESUMO

All-inorganic metal halide perovskites (MHPs) have attracted increasing attention because of their high thermal stability and band gap tunability. Among them, CsPbCl3 is considered a promising semiconductor material for visible-ultraviolet dual-band photodetectors because of its excellent photoelectric properties and suitable band gap value. In this work, we fabricated a visible-ultraviolet dual-band photodetector based on a CsPbCl3/p-GaN heterojunction using the spin coating method. The formation of the heterojunction enables the device to exhibit obvious dual-band response behavior at positive and negative bias voltages. At the same time, the dark current of the device can be as low as 2.42 × 10-9 A, and the corresponding detection rate can reach 5.82 × 1010 Jones. In addition, through simulation calculations, it was found that the heterojunction has a type II energy band arrangement, and the heterojunction response band light absorption is significantly enhanced. The type II energy band arrangement will separate electron-hole pairs more effectively, which will help improve device performance. The successful implementation of visible-ultraviolet dual-band photodetectors based on a CsPbCl3/p-GaN heterojunction provides guidance for the application of all-inorganic MHPs in the field of multi-band photodetectors.

7.
Int J Biol Macromol ; 262(Pt 2): 130191, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360245

RESUMO

Congenital cataract is a major cause of childhood blindness worldwide, with crystallin mutations accounting for over 40 % of gene-mutation-related cases. Our research focused on a novel R114C mutation in a Chinese family, resulting in bilateral coronary cataract with blue punctate opacity. Spectroscopic experiments revealed that ßA3-R114C significantly altered the senior structure, exhibiting aggregation, and reduced solubility at physiological temperature. The mutant also displayed decreased resistance and stability under environmental stresses such as UV irradiation, oxidative stress, and heat. Further, cellular models confirmed its heightened sensitivity to environmental stresses. These data suggest that the R114C mutation impairs the hydrogen bond network and structural stability of ßA3-crystallin, particularly at the boundary of the second Greek-key motif. This study revealed the pathological mechanism of ßA3-R114C and may help in the development of potential treatment strategies for related cataracts.


Assuntos
Catarata , Cadeia A de beta-Cristalina , Humanos , Catarata/genética , Catarata/metabolismo , Cristalinas/genética , Cristalinas/metabolismo , Mutação , Cadeia A de beta-Cristalina/genética
8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(6): 670-674, 2023 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-37331941

RESUMO

Objective: To investigate the effect of body mass index (BMI) on the short-term effectiveness of high tibial osteotomy (HTO) in the treatment of varus knee arthritis. Methods: The clinical data of 84 patients (84 knees) with varus knee arthritis treated with HTO between May 2016 and August 2020 were retrospectively analyzed. According to BMI, the patients were divided into normal group (32 patients in group A, BMI<25 kg/m 2), overweight group (27 patients in group B, BMI>30 kg/m 2), and obese group (25 patients in group C, BMI>30 kg/m 2). The BMI of groups A, B, and C were (23.35±0.89), (26.65±1.03), and (32.05±1.47) kg/m 2, respectively. There was no significant difference ( P>0.05) in gender, age, surgical side, disease duration, and preoperative Hospital for Special Surgery (HSS) score, visual analogue scale (VAS) score, knee range of motion, and hip-knee-ankle angle (HKA) between groups. The operation time, intraoperative dominant blood loss, and the decrease of hemoglobin on the 3rd day after operation were recorded and compared between groups. The improvement of knee joint function and pain status were evaluated by knee joint HSS score, knee range of motion, and VAS score before and after operation, and measuring the HKA of patients on X-ray film. During the follow-up, the X-ray films of the knee joint were reexamined to observe the position of the internal fixator and the healing of osteotomy. Results: All patients completed the operation successfully and were followed up 8-40 months (mean, 19.3 months). There was no significant difference in follow-up time, operation time, intraoperative dominant blood loss, and the decrease of hemoglobin on the 3rd day after operation between groups ( P>0.05). No operative complications such as severe vascular or nerve injury occurred. After operation, deep venous thrombosis of lower extremities occurred in 1 case in groups A and B respectively, and fat liquefaction of surgical incision occurred in 2 cases in group C. There was no significant difference in the incidence of perioperative complications between groups (3.1% vs. 3.7% vs. 8.0%) ( P=0.689). During the follow-up, there was no bone nonunion, plate fracture or loosening. At last follow-up, HSS score, VAS score, knee range of motion, and HKA significantly improved in the 3 groups when compared with those before operation ( P<0.05), but there was no significant difference in the differences of the above indexes between groups before and after operation ( P>0.05). Conclusion: BMI does not affect the short-term effectiveness of HTO in the treatment of varus knee arthritis. HTO can be selected for overweight and obese patients after standard medical treatment is ineffective.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/cirurgia , Índice de Massa Corporal , Sobrepeso , Estudos Retrospectivos , Resultado do Tratamento , Articulação do Joelho/cirurgia , Obesidade/complicações , Osteotomia , Perda Sanguínea Cirúrgica
9.
ACS Appl Mater Interfaces ; 15(48): 56014-56021, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37994881

RESUMO

Two-dimensional (2D) organic-inorganic hybrid perovskites (OIPs) have exhibited ideal prospects for perovskite photodetectors (PDs) owing to their remarkable environmental stability, tunable band gap, and structural diversity. However, most perovskites face the great challenge of a narrow spectral response. Integrating 2D OIPs with a suitable wide band gap semiconductor gives opportunities to broaden the response spectra. Here, a photodetector based on the BA2PbI4/GaN heterostructure with a broadband photoresponse covering from the ultraviolet (UV) to visible band is designed. We demonstrate that the device is capable of detecting in the UV region by p-GaN being integrated with BA2PbI4. The morphology and material optical properties of BA2PbI4 are characterized by transmission electron microscopy (TEM) and photoluminescence (PL). Additionally, the current-voltage (I-V) characteristics and photoresponses of the BA2PbI4/GaN heterojunction photodetector are investigated. The response spectrum of the photodetector is broadened from the visible to UV region, exhibiting good rectifying behavior in the dark conditions and a broadband photoresponse from the UV to the visible region. Additionally, the energy band is used to analyze the current mechanism of the BA2PbI4/GaN heterojunction PD. This study is expected to provide a new insight of optoelectronic devices by integrating 2D OIPs such as BA2PbI4 and wide-band-gap semiconductors such as GaN to broaden the response spectra.

10.
Membranes (Basel) ; 12(5)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35629812

RESUMO

Membrane fouling markedly influences the service life and performance of the membrane during the using process. Herein, hydrophilic polyvinylidene fluoride (PVDF) nanocomposite (P-GO-DAA) membranes with antifouling and anti-biofouling characteristics were fabricated by employing graphene oxide (GO) and different concentrations of D-Tyrosine. The structural properties of the prepared nanocomposite membranes as well as pure PVDF membranes were characterized using FTIR, XPS, SEM, AFM, and contact angle analysis. It was found that the introduction of GO fillers made an excellent antifouling performance compared to pure PVDF indicated by the pure water flux, flux recovery rate, and rejection rate during ultrafiltration experiments as a result of the formation of the hydrophilic and more porous membrane. In particular, the nanocomposite membranes showed an increased flux of 305.27 L/(m2·h) and the rejection of 93.40% for the mixed pollutants solution (including Bull Serum Albumin, Sodium Alginate, and Humic Acid). Besides, the outstanding anti-biofouling activity was shown by the P-GO-DAA membrane with the properties of D-Tyrosine for inhibiting biofilm formation during the bacterial adhesion experiments. Furthermore, the adhesion ratio of bacteria on the membrane was 26.64% of the P-GO-DAA membrane compared to 84.22% of pure PVDF. These results were confirmed by CLSM.

11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(9): 1103-1107, 2022 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-36111472

RESUMO

Objective: To investigate the effectiveness of a novel lateral tibial plateau annular plate (hereinafter referred to as the novel plate) fixation via fibular neck osteotomy approach for posterolateral tibial plateau fractures. Methods: Between January 2015 and December 2018, 22 patients with posterolateral tibial plateau fractures were treated. There were 10 males and 12 females with an average age of 39.0 years (range, 25-56 years). Seven fractures were caused by falls, 10 by traffic accidents, and 5 by falling from height. The time from injury to hospitalization ranged from 3 to 12 days, with an average of 7.0 days. All patients were closed fractures. According to Schatzker classification, the fractures were classified as type Ⅱ in 8 cases, type Ⅲ in 9 cases, type Ⅴ in 1 case, and type Ⅵ in 4 cases. The fractures were fixed with the novel plates after reduction via fibular neck osteotomy approach. The fracture reduction and healing were observed by X-ray film after operation. The range of motion of the knee joint was recorded and the function was evaluated by modified American Hospital for Special Surgery (HSS) score. Results: All operations were completed successfully. The operation time was 60-95 minutes (mean, 77.6 minutes). The intraoperative blood loss was 100-520 mL (mean, 214.5 mL). There was 1 case of common peroneal nerve injury during operation and 2 cases of fat liquefaction of incision after operation. All patients were followed up 13-32 months (mean, 19.4 months). Postoperative X-ray films showed that the fracture reduction was good in 17 cases and moderate in 5 cases, and all fractures healed with a healing time of 10-18 weeks (mean, 13.0 weeks). At last follow-up, the range of motion of the knee joint ranged from 100° to 145° in flexion (mean, 125.5°) and from 0° to 4° in extension (mean, 1.2°). The modified HSS score was 82-95 (mean, 86.3). There was no complications such as plate deformation, screw fracture, fracture reduction loss, skin necrosis, and so on. Conclusion: For posterolateral tibial plateau fractures, the novel plate fixation via fibular neck osteotomy approach has the advantages of clear intraoperative field, firm fracture fixation, and less postoperative complications, which is beneficial to the recovery of knee joint function.


Assuntos
Fixação Interna de Fraturas , Fraturas da Tíbia , Adulto , Placas Ósseas , Feminino , Humanos , Articulação do Joelho , Masculino , Osteotomia , Fraturas da Tíbia/cirurgia , Resultado do Tratamento
12.
ACS Appl Mater Interfaces ; 12(48): 53966-53972, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33179912

RESUMO

The ability to pattern planar and freestanding 3D metallic architectures would enable numerous applications, including flexible electronics, displays, sensors, and antennas. Low melting point metals, such as gallium, have recently drawn considerable attention especially in the fields of flexible and stretchable electronics and devices owing to its unique properties, such as excellent electrical conductivity and fluidity. However, the large surface tension, low viscosity, and large density pose great challenges to 3D printing of freestanding gallium structures in a large scale, which hinder its further applications. In this article, we first propose an electrochemically enabled embedded 3D printing (3e-3DP) method for creating planar and freestanding gallium wire-like structures assisted with supporting hydrogel. After an enhanced solidification process and the removal of hydrogel, various freestanding 2D and 3D wire-like structures are realized. By simply reassembling the gallium structure into soft elastomer, a gallium-based flexible conductor and a 3D-spiral pressure sensor are demonstrated. Above all, this study presents a brand-new and economical way for the fabrication of 2D and 3D freestanding gallium structures, which has great prospects in wide applications in flexible and stretchable electronics and devices.

13.
RSC Adv ; 9(5): 2353-2359, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35520505

RESUMO

In this study, an electric field was used to regulate and control pseudopodia-like extensions of a liquid metal-Al (LM-Al) droplet in certain directions. The results suggest that in certain electric fields, the LM-Al droplets tend to generate extensions perpendicular to the electric field; the underlying mechanism arises from the specific surface tension imbalance induced by the electric field. The influence of varying electric field intensity and Al content on the LM-Al transformations was also evaluated; the LM-Al droplets displayed specific and distinct behaviors according to each experimental configuration; this further proved the feasibility of using electric fields for controlling LM-Al transformations. The entire study provides a promising and practical method for control of LM amoeba-like transformations, which are valuable for further development of soft robots and devices.

14.
ACS Appl Mater Interfaces ; 11(8): 8685-8692, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30768235

RESUMO

In the present study, a magnetic liquid metal droplet (MLMD), which can be stretched in large scales both horizontally and vertically in the free space, is introduced. This MLMD is fabricated based on a multimaterial system including liquid metals, iron particles, and electrolytes. Such remarkable stretching capacity is reversible, long-lasting, and can be repeated for multiple times. The seemingly contrary properties, the good stretchability and the mechanic strength for three-dimensional (3D) stretch, should owe to the surface oxide over the MLMD. On the basis of the 3D stretching ability of the MLMD, an intelligent scalable conductor was achieved, which can make electrical connections at various directions in the 3D free space. Moreover, the vertically stretched MLMD can move horizontally with its half body in the solution and the other half in the air, which resembles the nature of an upright walking amphibian. All the behaviors can be precisely, conveniently, and contactlessly controlled by the magnetic field provided by permanent magnets. With all the appealing properties, this MLMD presents a fundamental and promising platform for the liquid metals to further develop the multi-freedom actuation in free space and eventually lead to the dynamically reconfigurable intelligent and biomimetic soft robots in the future.

15.
RSC Adv ; 9(10): 5738-5741, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35515917

RESUMO

N-heterocyclic carbene-palladium(ii)-catalyzed cross-coupling of benzylammonium salts with arylboronic acids for the synthesis of diarylmethane derivatives via C-N bond activation has been developed. Notably, in the presence of the easily prepared and bench-stable Pd-PEPPSI precatalyst, the Csp3-N bond activation of the benzylammonium salt even proceeded smoothly in isopropanol at room temperature.

16.
Int J Cardiovasc Imaging ; 31(8): 1571-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26288953

RESUMO

To assess whether global and regional myocardial strains from three-dimensional speckle tracking echocardiography (3D-STE) correlate with myocardial infarction size (MIS) detected by single photon emission computed tomography (SPECT). Fifty-seven patients with a history of ST-segment elevation myocardial infarction (MI) within 3-6 months were enrolled, alongside 24 healthy volunteers. Left ventricular (LV) global area strain, global longitudinal strain (GLS), global radial strain, global circumferential strain, left ventricular ejection fraction (LVEF) and wall motion score index (WMSI) were measured and compared with the corresponding SPECT-detected MISs. Patients were sub-grouped into massive MIS group (MIS ≥ 12%) and small MIS group (MIS < 12%). Myocardial strains of all the LV segments were compared with the corresponding MIS. Global myocardial strain parameters, LVEF and WMSI of the patients were significantly different from the control group (all P < 0.05) and correlated well with MISs, most significantly for GLS (r = 0.728, P < 0.01). Significant differences in myocardial strain parameters were found between the massive and small MIS groups (all P < 0.05). Receiver operating characteristic curve analysis indicated that GLS had a highest diagnostic value and when the cutoff was -13.8%, the area under the curve was 0.84, with the 70.6% sensitivity and 87.5% specificity. Significant differences of myocardial strain parameters were observed between segments with and without transmural MIs (P < 0.01). 3D-STE myocardial strain parameters evaluated LV global MIS, 3D GLS had the highest diagnostic value. It also preliminarily gauged the degree of ischemia and necrosis of regional myocardial segments.


Assuntos
Ecocardiografia Tridimensional , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio/patologia , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Fenômenos Biomecânicos , Estudos de Casos e Controles , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Contração Miocárdica , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Necrose , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estresse Mecânico , Volume Sistólico , Função Ventricular Esquerda
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