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1.
Talanta ; 278: 126495, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38955105

RESUMO

Accurate and sensitive determination of human immunoglobulin G (HIgG) level is critical for diagnosis and treatment of various diseases, including rheumatoid arthritis, humoral immunodeficiencies, and infectious disease. In this study, versatile tri-signal probes were developed by preparing CdS@SiO2 nanorods that integrate photoluminescence (PL), multi-phonon resonant Raman scattering (MRRS) and infrared absorption (IRA) properties. Through the coating of multiple CdS nanoparticles as cores within SiO2 shells, the PL and MRRS properties of CdS were improved, resulting in a significantly lowered limit of detection (LOD), with the lowest LOD of 12.37 ag mL-1. Integration with the distinctive IRA property of SiO2 shells widened the detection range towards higher concentrations, establishing a final linear range of 50 ag mL-1 to 10 µg mL-1. The remarkable consistency among the three signals highlighted the robust internal verification capability for accurate detection. This approach enhances flexibility in selecting detection methodologies to suit diverse scenarios, facilitating HIgG detection. The tri-signal nanoprobes also exhibited excellent detection selectivity, specificity and repeatability. This study presents a fresh idea for developing high-performance detection strategies.

2.
IEEE Trans Image Process ; 33: 4104-4115, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38954579

RESUMO

Few-shot learning (FSL) aims at recognizing a novel object under limited training samples. A robust feature extractor (backbone) can significantly improve the recognition performance of the FSL model. However, training an effective backbone is a challenging issue since 1) designing and validating structures of backbones are time-consuming and expensive processes, and 2) a backbone trained on the known (base) categories is more inclined to focus on the textures of the objects it learns, which is hard to describe the novel samples. To solve these problems, we propose a feature mixture operation on the pre-trained (fixed) features: 1) We replace a part of the values of the feature map from a novel category with the content of other feature maps to increase the generalizability and diversity of training samples, which avoids retraining a complex backbone with high computational costs. 2) We use the similarities between the features to constrain the mixture operation, which helps the classifier focus on the representations of the novel object where these representations are hidden in the features from the pre-trained backbone with biased training. Experimental studies on five benchmark datasets in both inductive and transductive settings demonstrate the effectiveness of our feature mixture (FM). Specifically, compared with the baseline on the Mini-ImageNet dataset, it achieves 3.8% and 4.2% accuracy improvements for 1 and 5 training samples, respectively. Additionally, the proposed mixture operation can be used to improve other existing FSL methods based on backbone training.

3.
Adv Mater ; : e2314156, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822705

RESUMO

Adaptive processing allows sensory systems to autonomically adjust their sensitivity with exposure to a constant sensory stimulus and thus organisms to adapt to environmental variations. Bioinspired electronics with adaptive functions are highly desirable for the development of neuromorphic sensory systems (NSSs). Herein, the functions of desensitization and sensitivity changing with background intensity (i.e., Weber's law), as two fundamental cues of sensory adaptation, are biorealistically demonstrated in an Ag nanowire (NW)-embedded sodium alginate (SA) based complementary memristor. In particular, Weber's law is experimentally emulated in a single complementary memristor. Furthermore, three types of adaptive NSS unit are constructed to realize a multiple perceptual capability that processes the stimuli of illuminance, temperature, and pressure signals. Taking neuromorphic vision as an example, scotopic and photopic adaptation functions are well reproduced for image enhancement against dark and bright backgrounds. Importantly, an NSS system with multisensory integration function is demonstrated by combining light and pressure spikes, where the accuracy of pattern recognition is obviously enhanced relative to that of an individual sense. This work offers a new strategy for developing neuromorphic electronics with adaptive functions and paves the way toward developing a highly efficient NSS.

4.
ACS Appl Mater Interfaces ; 16(27): 35293-35302, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38940838

RESUMO

Ferroelectric materials have aroused increasing interest in the field of self-powered ultraviolet (UV) photodetectors (PDs) for their switchable spontaneous polarization. However, the utilization of ferroelectric materials to modulate the built-in electric field and energy band at the junction interface has rarely been investigated. Herein, we design and fabricate self-powered solar-blind UV PDs based on a Ga2O3/ZnO:V heterojunction. The performance of the Ga2O3/ZnO:V PD is significantly enhanced through the reasonable coupling of ferroelectricity and piezoelectricity within the ZnO:V film. The device at 260 nm exhibits excellent photoelectric properties with high peak responsivity of 64.5 mA/W, a specific detectivity of 3.8 × 1010 Jones, and a rise/decay time of 1.9/45.2 µs, together with reproducibility and stability. Systematical energy band diagram analysis reveals that the excellent performance of Ga2O3/ZnO:V PD can be attributed to the driving forces arising from the addition of the depolarization field and piezoelectric field, which increases the intensity of built-in electric field and promotes the separation and transport of photogenerated carriers at the heterojunction interface. The findings of our research provide a novel avenue and valuable guidance for the design of high-performance self-powered photodetectors.

5.
Nano Lett ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753313

RESUMO

Carrier multiplication (CM) in semiconductors, the process of absorbing a single high-energy photon to form two or more electron-hole pairs, offers great potential for the high-response detection of high-energy photons in the ultraviolet spectrum. However, compared to two-dimensional semiconductors, conventional bulk semiconductors not only face integration and flexibility bottlenecks but also exhibit inferior CM performance. To attain efficient CM for ultraviolet detection, we designed a two-terminal photodetector featuring a unilateral Schottky junction based on a two-dimensional γ-InSe/graphene heterostructure. Benefiting from a strong built-in electric field, the photogenerated high-energy electrons in γ-InSe, an ideal ultraviolet light-absorbing layer, can efficiently transfer to graphene without cooling. It results in efficient CM within the graphene, yielding an ultrahigh responsivity of 468 mA/W and a record-high external quantum efficiency of 161.2% when it is exposed to 360 nm light at zero bias. This work provides valuable insights into developing next-generation ultraviolet photodetectors with high performance and low-power consumption.

6.
Vaccines (Basel) ; 12(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38400158

RESUMO

The Omicron EG.5 lineage of SARS-CoV-2 is currently on a trajectory to become the dominant strain. This phase 2 study aims to evaluate the immunogenicity of SCTV01E-2, a tetravalent protein vaccine, with a specific emphasis on its immunogenicity against Omicron EG.5, comparing it with its progenitor vaccine, SCTV01E (NCT05933512). As of 12 September 2023, 429 participants aged ≥18 years were randomized into the groups SCTV01E (N = 215) and SCTV01E-2 (N = 214). Both vaccines showed increases in neutralizing antibody (nAb) against Omicron EG.5, with a 5.7-fold increase and a 9.0-fold increase in the SCTV01E and SCTV01E-2 groups 14 days post-vaccination, respectively. The predetermined statistical endpoints were achieved, showing that the geometric mean titer (GMT) of nAb and the seroresponse rate (SRR) against Omicron EG.5 were significantly higher in the SCTV01E-2 group than in the SCTV01E group. Additionally, SCTV01E and SCTV01E-2 induced a 5.5-fold and a 5.9-fold increase in nAb against XBB.1, respectively. Reactogenicity was generally mild and transient. No vaccine-related serious adverse events (SAEs), adverse events of special interest (AESIs), or deaths were reported. In summary, SCTV01E-2 elicited robust neutralizing responses against Omicron EG.5 and XBB.1 without raising safety concerns, highlighting its potential as a versatile COVID-19 vaccine against SARS-CoV-2 variants.

7.
Arch Biochem Biophys ; 753: 109903, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38253248

RESUMO

OBJECTIVE: To explore the role of HIF-1α in hypercoagulable state of COPD induced by lipopolysaccharide plus smoking in rats. It also has to explore the regulatory mechanism of HIF-1α-EPO/EDN-1/VEGF pathway by using its activator and inhibitor. METHODS: 60 Sprague-Dawley rats (SD rats) were randomly divided into healthy control group, COPD hypercoagulable control group, activator group, and inhibitor group with 15 rats in each group. The healthy control group was fed freely. The other groups were given smoke and lipopolysaccharide by tracheal instillation to establish the experimental animal model of COPD hypercoagulability. After successful modeling, each experimental group was given 0.9 % sodium chloride solution and corresponding drugs by intraperitoneal injection for 7 days. Lung function was detected after drug administration. Hematoxylin-eosin staining was used to observe the pathological changes of lung tissue. Enzyme-linked immunosorbent assay was used to detect serum D-D,F (1 + 2),IL-6,TNF-α. The mRNA expressions of HIF-1α, EPO, EDN-1, and VEGF were detected by RT-PCR. Western-Blot and IHC were used to detect the expression of HIF-1α, EPO, EDN-1, and VEGF in lung tissue of rats. RESULTS: Compared with the healthy control group, rats in COPD hypercoagulable control group had COPD symptoms/signs, decreased lung function, increased the expression of serum D-D and F (1 + 2), increased the expression of inflammatory factors IL-6,TNF-α, and increased the expression of proteins HIF-1α, EPO, EDN-1 and VEGF. Compared with COPD hypercoagulable control group, lung function in activator group and inhibitor group had no obvious changes. The expressions of serum D-D,F (1 + 2),IL-6,TNF-α in activator group have increased noticeably. The expressions of proteins HIF-1α, EPO, EDN-1, and VEGF have further increased. Compared with COPD hypercoagulable control group, the expression of serum D-D, F (1 + 2), HIF-1α, EPO, EDN-1, and VEGF in the inhibitor group decreased. CONCLUSION: HIF-1α-EPO/EDN-1/VEGF pathway plays an important role in the hypercoagulable state of COPD. HIF-1α inhibitor can improve airway inflammation and reduce hypercoagulability in COPD model rats.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Trombofilia , Animais , Ratos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Interleucina-6 , Lipopolissacarídeos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/metabolismo , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
ACS Nano ; 18(4): 2906-2916, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252027

RESUMO

Hydrogels are emerging as stretchable electromagnetic interference (EMI) shielding materials because of their tissue-like mechanical properties and water-rich porous cellular structures. However, achieving high-performance hydrogel shields remains a challenge because enhancing conductivity often results in a compromise in deformation adoptability. This work proposes a treatment strategy involving sulfuric acid/titanium carbide MXene, which can simultaneously enhance the conductivity and stretchability of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/poly(vinyl alcohol) (PVA) double-network hydrogels. Multiple spectroscopic characterizations reveal that sulfuric acid promotes the linear conformation transition of the PEDOT molecular chain, while MXene increases charge delocalization and hydrogen bond cross-linking sites. The hydrogels, synthesized with a combined content of 0.6 wt % of MXene and PEDOT:PSS, exhibit an average X-band EMI SE of 41 dB. This performance is sustained at 94.5%, even following stretching and release at a strain of 200%. Interestingly, the EMI SE is found to linearly increase, reaching a value of 99 dB as the frequency is increased to 26.5 GHz. This increase is attributed to the enhanced water molecular polarization process, as supported by theoretical calculations of the impedance and attenuation constant. This work introduces a post-treatment technique that optimizes double-network hydrogels, providing deep insights into their EMI shielding mechanism and enabling high-performance EMI shielding with an ultralow conductive filler content.

9.
Sci Total Environ ; 914: 169856, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190916

RESUMO

Waste polyethylene terephthalate (PET) with high carbon content (>60 wt%) has shown great potential in the field of synthesizing carbon materials for CO2 capture, attracting increasing attention. Herein, an innovative strategy was proposed to synthesize nitrogen-doped hierarchical porous carbon (PC) for CO2 capture using PET as precursor and sodium amide (NaNH2) as both nitrogen dopant and low-temperature activator. As-synthesized N-doped PC exhibited a significantly high micropore volume of 0.755 cm3/g and a rich content of N- and O-containing functional groups, offering ample active sites for CO2 molecules. Further, the adsorbents demonstrated excellent CO2 capture capacity, achieving 5.7 mmol/g (0 °C) and 3.3 mmol/g (25 °C) at 1 bar, respectively. This was primarily attributed to the synergistic effect of narrow micropores filling and electrostatic interactions. Moreover, as-synthesized PC exhibited rapid CO2 adsorption capability, and its dynamic adsorption process was effectively described using a pseudo-second-order kinetic model. After five consecutive cycles, PET-derived PC still maintained ~100 % of adsorption capacity. They also possessed good CO2/N2 selectivity and reasonable isosteric heat of adsorption. Therefore, as-synthesized nitrogen-doped PC is a promising CO2 adsorbent through low-temperature activation of carbonized PET with NaNH2. Such findings have substantial implications for waste plastic recycling and mitigating the greenhouse effect.

10.
Chemosphere ; 349: 140783, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043618

RESUMO

Ornidazole (ONZ), a nitroimidazole antibiotic detected in water bodies, may negatively impact the aquatic ecosystem. Its reaction kinetics during ozonation which is a feasible and applicable technology to control the contamination of emerging contaminants, however, has not been reported in literature. In this study, we measured the apparent second-order kinetic constant of ONZ with ozone molecules via the excessive ozone method and the competing method which led to an average value of 103.8 ± 2.7 M-1 s-1 at pH 7. The apparent second-order kinetic constant of ONZ with HO• was calculated to be 4.65 × 109 M-1 s-1 with the concept of Rct measured via para-chlorobenzoic acid as a probe. The transformation products (TPs) of ONZ during ozonation at pH 3 and pH 11 were separately analyzed with HPLC-MS/MS and some unique products were found at pH 11, reflecting the influence of HO•. The toxicity of individual TPs was predicted with the tool of T.E.S.T. It was found that 62% of 21 identified TPs could be more toxic than ONZ in terms of at least one acute toxicity endpoint, including chlorinated amines and N-oxides. The analysis with a respirometer further revealed that the toxicity of mixing TPs generated at HO• rich conditions was slightly lower than O3 dominated conditions. In general, this study provides the basic kinetic data for designing ozonation processes to eliminate ONZ and the important reference for understanding the toxicity evolution of ONZ during ozonation.


Assuntos
Ornidazol , Ozônio , Poluentes Químicos da Água , Purificação da Água , Oxirredução , Espectrometria de Massas em Tandem , Ecossistema , Poluentes Químicos da Água/química , Cinética , Ozônio/química , Purificação da Água/métodos
11.
Adv Mater ; 36(7): e2306772, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37661841

RESUMO

The vector characteristics of light and the vectorial transformations during its transmission lay a foundation for polarized photodetection of objects, which broadens the applications of related detectors in complex environments. With the breakthrough of low-dimensional materials (LDMs) in optics and electronics over the past few years, the combination of these novel LDMs and traditional working modes is expected to bring new development opportunities in this field. Here, the state-of-the-art progress of LDMs, as polarization-sensitive components in polarized photodetection and even the imaging, is the main focus, with emphasis on the relationship between traditional working principle of polarized photodetectors (PPs) and photoresponse mechanisms of LDMs. Particularly, from the view of constitutive equations, the existing works are reorganized, reclassified, and reviewed. Perspectives on the opportunities and challenges are also discussed. It is hoped that this work can provide a more general overview in the use of LDMs in this field, sorting out the way of related devices for "more than Moore" or even the "beyond Moore" research.

12.
Opt Express ; 31(25): 41105-41116, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087518

RESUMO

Polarization and focal length are both critical optical parameters with many applications in many fields, such as optical communications and imaging. The development of metasurfaces provides a new realization of optical systems. In this paper, based on metasurfaces' powerful electromagnetic modulation capability, we integrate polarization conversion with continuous zoom function and propose a dynamic polarization-regulated metasurface with variable focal length. It realizes the reversible conversion of polarization state, which can convert linearly polarized light into elliptically polarized light and circularly polarized light and convert circularly polarized light to linearly polarized light. At the same time, it achieves a 4.4× zoom range, with a constant focal length variation from 70 µm to 309 µm. The metasurface has the advantages of small size, easy integration, and reconfigurability, providing a new design idea for complex functional optical systems.

13.
Am J Transl Res ; 15(8): 5519-5527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692932

RESUMO

OBJECTIVE: To analyze the therapeutic effect of acupuncture combined with mifepristone on uterine fibroids and its influence on sex hormones and inflammatory factors. METHODS: Data of 102 patients with uterine fibroids admitted to Shanxi Provincial Hospital of Chinese Medicine from January 2019 to January 2022 were retrospectively analyzed. Among them, there were 50 patients treated with mifepristone alone (control group) and 52 patients undergoing combined treatment of acupuncture and mifepristone (observation group). After 2 months of continuous treatment, the therapeutic efficacy, volume of uterine fibroids and uterus, levels of inflammatory factors (C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α)), as well as levels of estradiol (E2), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), along with hemodynamic levels and incidence of adverse reactions were recorded and compared between the two groups. Logistic analysis was employed to identify the independent risk factors for the recurrence of uterine fibroids in patients. RESULTS: Compared with the control group, the observation group was identified with significantly higher overall response rate (P < 0.05). The uterine fibroid volume and uterine volume significantly improved in both groups after treatment, and the improvements were more prominent in the observation group than in the control group (P < 0.05). After treatment, the serum CRP and TNF-α were both evidently decreased in the two groups, while levels of E2, FSH, LH and peak blood flow velocity were significantly ameliorated, and the improvements in the observation group were more significant than those in the control group (P < 0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P > 0.05). Alcohol intake and treatment regime were independent risk factors for the recurrence of uterine fibroids in patients. CONCLUSION: Combining acupuncture with mifepristone can significantly improve uterine fibroids, estrogen and progesterone levels, as well as reduce inflammation, with a high level of safety, making it a promising treatment for clinical use.

14.
ACS Appl Mater Interfaces ; 15(32): 38612-38622, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37531140

RESUMO

We have achieved significantly improved device performance in solar-blind deep-ultraviolet photodetectors fabricated from ß-Ga2O3 thin films grown via metal-organic chemical vapor deposition (MOCVD) on p-Si(111) substrates by improving material quality through the use of an AlN buffer layer. High-structural-quality ß-Ga2O3 films with a (-201) preferred orientation are obtained after the introduction of the AlN buffer. Under 3 V bias, the dark current reaches a minimum of 45 fA, and the photo-to-dark current ratio (PDCR) reaches 8.5 × 105 in the photodetector with the metal-semiconductor-metal (MSM) structure. The peak responsivity and detectivity are 38.8 A/W and 2.27 × 1015 cm·Hz1/2/W, respectively, which are 16.5 and 230 times that without the buffer layer. Additionally, benefiting from the introduction of the AlN layer, the photodetection performance of the ß-Ga2O3/AlN/Si heterojunction is significantly improved. The PDCR, peak responsivity, and detectivity for the ß-Ga2O3/AlN/p-Si photodetector at 5 V bias are 2.7 × 103, 11.84 A/W, and 8.31 × 1013 cm·Hz1/2/W, respectively. The improved structural quality of ß-Ga2O3 is mainly attributed to the decreased in-plane lattice mismatch of 2.3% for ß-Ga2O3(-201)/AlN(002) compared to that of 20.83% for ß-Ga2O3(-201)/Si(111), as well as the elimination of the native amorphous SiOx surface layer on the Si substrate during the initial growth of oxide thin films.

15.
Int J Biol Macromol ; 250: 126330, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37579898

RESUMO

Levan is a high-valued ß-(2,6)-linked fructan with promising physicochemical and physiological properties and has diverse potential applications in the food, nutraceutical, pharmaceutical and cosmetic industry, but its commercial availability is still restricted to the relatively high costs of production. In this study, a strain identified as Microbacterium sp. XL1 was isolated from soil and highly produced exopolysaccharide (EPS). HPLC, FTIR and NMR spectroscopy revealed XL1-EPS is a levan-type fructan connected by ß-(2, 6) linkages. SEM, DLS and TGA-DSC analysis showed that XL1-EPS processed high morphological versatility, narrow size distribution in its solutions and excellent thermal stability. The levan yield reached 83.67 ± 4.06 g/L with corresponding productivity of 3.49 ± 0.17 g/L/h and a conversion yield of 39.8 ± 1.9 % using sucrose (210 g/L) as substrates under the optimal cultivation conditions concluded by the response surface methodology (RSM). More strikingly, the XL1 strain also has multi-type fructanases to generate levanbiose, kestose, DFA IV and other L-FOSs. These results suggest Microbacterium sp. XL1 is a promising strain to produce levan and can provide various levan/inulin-degrading enzymes to create a great diversity of FOSs.

16.
Cardiovasc Diagn Ther ; 13(2): 355-366, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37583686

RESUMO

Background: Following carotid artery stenting (CAS), new ipsilateral ischemic lesions (NIILs) in the brain are frequently seen using diffusion-weighted imaging (DWI). This study's goal was to identify the imaging characteristics associated with NIILs after CAS by high-resolution magnetic resonance vessel wall imaging (HR-VWI). Methods: This was a case-control study. 109 patients who received CAS for atherosclerotic carotid stenosis were retrospectively collected and categorized into NIILs positive and NIILs negative groups. Based on the existence or absence of stroke symptoms after CAS, the NIILs positive group was split into two subgroups: the NIILs symptomatic group and the NIILs asymptomatic group. Patients underwent preoperative HR-VWI and brain magnetic resonance imaging (MRI) within 7 days preoperatively and within 3 days postoperatively. Quantitatively assess carotid plaque burden and components using HR-VWI. The baseline and HR-VWI imaging characteristics of all patients were retrospectively analyzed. To ascertain the imaging characteristics connected with NIILs after CAS, logistic regression analysis was carried out. Results: Among 109 patients, 38 patients (34.9%) developed NIILs after CAS. Six patients (5.5%) developed symptomatic stroke with NIILs. The logistic regression analysis revealed that maximum wall thickness (Max WT) [odds ratio (OR), 1.53; 95% confidence interval (CI): 1.20-1.96; P=0.001], the maximum area percentage of lipid-rich necrotic core (LRNC) (OR, 1.05; 95% CI: 1.03-1.07; P<0.001), the volume of LRNC (OR, 1.004; 95% CI: 1.002-1.005; P<0.001), the maximum area percentage of intraplaque hemorrhage (IPH) (OR, 1.17; 95% CI: 1.11-1.24; P<0.001), the volume of IPH (OR, 1.06; 95% CI: 1.03-1.08; P<0.001), and maximum circumference score of calcification in a single slice (OR, 1.66; 95% CI: 1.04-2.63; P=0.03) were linked with NIILs following CAS. Conclusions: The massive IPH, LRNC, and heavy circumferential calcification were associated with NIILs after CAS. Preoperative quantitative assessment of carotid plaque using HR-VWI may be useful for predicting NIILs following CAS.

17.
Quant Imaging Med Surg ; 13(7): 4493-4503, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37456317

RESUMO

Background: The plaque imaging findings associated with the stent expansion rate (SER) of the carotid artery are not well known. The purpose of this study was to investigate the imaging findings associated with SER. Methods: It was a retrospective investigation. Based on the kind of carotid stents used, retrospective data from 89 patients who had carotid artery stenting (CAS) for atherosclerotic carotid stenosis were gathered and divided into two groups: open-cell stents and closed-cell stents. Patients underwent preoperative carotid high-resolution magnetic resonance vessel wall imaging (HR-VWI). Use HR-VWI to quantitatively evaluate carotid wall thickness and plaque components. Calculate SER using digital subtraction angiography (DSA). All patients' baseline and HR-VWI imaging features were retrospectively analyzed. Simple and multivariable linear regression analysis was used to determine the imaging findings associated with SER of open-cell and closed-cell stents. Results: A total of 89 patients (mean age, 70±8 years; 69 men) were included in the final analysis. Among 89 patients, 35 patients were treated with open-cell stents. Fifty-four patients were treated with closed-cell stents. In the open-cell stents group, the Maximum single-slice calcification circumference score, maximum wall thickness (WTmax), and total calcification location score with P<0.10 in the simple linear regression analysis were included in the multivariable linear regression analysis. The results of the multivariable linear regression revealed that only the Maximum single-slice calcification circumference score (ß=-9.35; 95% CI: -18.15 to -0.56; P=0.03) was associated with SER of open-cell stents. In the closed-cell stents group, the Maximum single-slice calcification circumference score, WTmax, maximum area percentage of calcification, calcification volume, and total calcification location score with P<0.10 in the simple linear regression analysis were included in the multivariable linear regression analysis. The results of the multivariable linear regression revealed that the Maximum area percentage of calcification (ß=-0.67; 95% CI: -1.29 to -0.05; P=0.03), Maximum single-slice calcification circumference score (ß=-8.43; 95% CI: -13.36 to -3.49; P=0.001) and total calcification location score (ß=-0.37; 95% CI: -1.08 to 0.09; P=0.02) were associated with SER of closed-cell stents. Conclusions: Calcified plaques are associated with SER of the carotid artery. Calcification circumference correlates with SER of open-cell stents. Calcification circumference, calcification area, and calcification location are related to SER of closed-cell stents, which may provide a new consideration for clinicians when choosing carotid artery stents.

18.
Light Sci Appl ; 12(1): 180, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488112

RESUMO

Visual adaptation that can autonomously adjust the response to light stimuli is a basic function of artificial visual systems for intelligent bionic robots. To improve efficiency and reduce complexity, artificial visual systems with integrated visual adaptation functions based on a single device should be developed to replace traditional approaches that require complex circuitry and algorithms. Here, we have developed a single two-terminal opto-sensor based on multilayer γ-InSe flakes, which successfully emulated the visual adaptation behaviors with a new working mechanism combining the photo-pyroelectric and photo-thermoelectric effect. The device can operate in self-powered mode and exhibit good human-eye-like adaptation behaviors, which include broadband light-sensing image adaptation (from ultraviolet to near-infrared), near-complete photosensitivity recovery (99.6%), and synergetic visual adaptation, encouraging the advancement of intelligent opto-sensors and machine vision systems.

19.
Nanoscale ; 15(16): 7460-7465, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37014636

RESUMO

We report a high performance UVB photodetector with a metal-semiconductor-metal device structure based on high crystal quality SnO2 microwires prepared by chemical vapor deposition. Under 10 V bias, a low dark current of 3.69 × 10-9 A and a high light-to-dark current ratio of 1630 were achieved. The device showed a high responsivity of about 1353.0 A·W-1 under 322 nm light illumination. The detectivity of the device is as high as 5.4 × 1014 Jones, which ensures the detection of weak signals in the UVB spectral region. Due to the small amount of deep-level defect-induced carrier recombination, the light response rise time and fall time are shorter than 0.08 s.

20.
Small Methods ; 7(7): e2300041, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37096880

RESUMO

This work reports a high-detectivity solar-blind deep ultraviolet photodetector with a fast response speed, based on a nitrogen-doped graphene/ßGa2 O3 /GaN p-i-n heterojunction. The i layer of ßGa2 O3 with a Fermi level lower than the central level of the forbidden band of 0.2 eV is obtained by reversed substitution growth with oxygen replacing nitrogen in the GaN matrix, indicating the majority carrier is hole. X-ray diffractometershows that the transformation of GaN into ßGa2 O3 with (-201) preferred orientation at temperature above 900 °C in an oxygen ambient. The heterojunction shows enhanced self-powered solar blind detection ability with a response time of 3.2 µs (rise)/0.02 ms (delay) and a detectivity exceeding 1012 Jones. Under a reverse bias of -5 V, the photoresponsivity is 8.3 A W-1 with a high Ilight /Idark ratio of over 106 and a detectivity of ≈9 × 1014 Jones. The excellent performance of the device is attributed to 1) the continuous conduction band without a potential energy barrier, 2) the larger built-in potential in the heterojunction because of the downward shift of Fermi energy level in ß-Ga2 O3 , and 3) an enhanced built-in electric field in the ßGa2 O3 due to introducing p-type graphene with a high hole concentration of up to ≈1020 cm-3 .

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