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1.
Nano Lett ; 23(8): 3326-3333, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026788

RESUMO

On-chip photonic systems play crucial roles in nanoscience and nanoapplications, but coupling external light to these subwavelength devices is challenging due to a large mode mismatch. Here, we establish a new scheme for realizing highly miniaturized couplers for efficiently exciting on-chip photonic devices in a controllable way. Relying on both resonant and Pancharatnam-Berry mechanisms, our meta-device can couple circularly polarized light to a surface plasmon, which is then focused into a spot placed with a target on-chip device. We experimentally demonstrate two meta-couplers. The first can excite an on-chip waveguide (with a 0.1λ × 0.2λ cross section) with an absolute efficiency of 51%, while the second can achieve incident spin-selective excitation of a dual-waveguide system. Background-free excitation of a gap-plasmon nanocavity with the local field enhanced by >1000 times is numerically demonstrated. Such a scheme connects efficiently propagating light in free space and localized fields in on-chip devices, being highly favored in many integration-optics applications.

2.
Sensors (Basel) ; 23(9)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37177751

RESUMO

Petrochemical equipment tracking is a fundamental and important technology in petrochemical industry security monitoring, equipment working risk analysis, and other applications. In complex scenes where the multiple pipelines present different directions and many kinds of equipment have huge scale and shape variation in seriously mutual occlusions captured by moving cameras, the accuracy and speed of petrochemical equipment tracking would be limited because of the false and missed tracking of equipment with extreme sizes and severe occlusion, due to image quality, equipment scale, light, and other factors. In this paper, a new multiple petrochemical equipment tracking method is proposed by combining an improved Yolov7 network with attention mechanism and small target perceive layer and a hybrid matching that incorporates deep feature and traditional texture and location feature. The model incorporates the advantages of channel and spatial attention module into the improved Yolov7 detector and Siamese neural network for similarity matching. The proposed model is validated on the self-built petrochemical equipment video data set and the experimental results show it achieves a competitive performance in comparison with the related state-of-the-art tracking algorithms.

3.
Opt Lett ; 47(11): 2754-2757, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35648922

RESUMO

The polarization singularities in momentum space, rather than in real space, are capturing interest for active singular optics with exotic light scattering and various topological phenomena, which have potential applications in vortex nano-lasers, valley exciton emission, and others. Here, we propose to magnetically control the polarization singularities in momentum space in the photonic crystal slabs with inversion spatial symmetry (P symmetry). A pair of C points (circular polarization points) with the same topological charge is spawned from a V point (polarization vortex center), and they can be dynamically shifted in momentum space with the variation of the magnetic field. Moreover, the coupling between transverse electric (TE) and transverse magnetic (TM) modes induced by the magnetic field gives rise to a hybrid mode, which can close certain leaky channels to achieve an accidental V point. Such active manipulation of polarization singularities with magnetic field is promised for various applications in light-matter interactions and reveals novel phenomena and physics in singular optics and topological photonics.

4.
J Mol Cell Cardiol ; 161: 9-22, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34339758

RESUMO

OBJECTIVE: Pulmonary vascular remodeling due to excessive growth factor production and pulmonary artery smooth muscle cells (PASMCs) proliferation is the hallmark feature of pulmonary arterial hypertension (PAH). Recent studies suggest that miR-663 is a potent modulator for tumorigenesis and atherosclerosis. However, whether miR-663 involves in pulmonary vascular remodeling is still unclear. METHODS AND RESULTS: By using quantitative RT-PCR, we found that miR-663 was highly expressed in normal human PASMCs. In contrast, circulating level of miR-663 dramatically reduced in PAH patients. In addition, in situ hybridization showed that expression of miR-663 was decreased in pulmonary vasculature of PAH patients. Furthermore, MTT and cell scratch-wound assay showed that transfection of miR-663 mimics significantly inhibited platelet derived growth factor (PDGF)-induced PASMCs proliferation and migration, while knockdown of miR-663 expression enhanced these effects. Mechanistically, dual-luciferase reporter assay revealed that miR-663 directly targets the 3'UTR of TGF-ß1. Moreover, western blots and ELISA results showed that miR-663 decreased PDGF-induced TGF-ß1 expression and secretion, which in turn suppressed the downstream smad2/3 phosphorylation and collagen I expression. Finally, intratracheal instillation of adeno-miR-663 efficiently inhibited the development of pulmonary vascular remodeling and right ventricular hypertrophy in monocrotaline (MCT)-induced PAH rat models. CONCLUSION: These results indicate that miR-663 is a potential biomarker for PAH. MiR-663 decreases PDGF-BB-induced PASMCs proliferation and prevents pulmonary vascular remodeling and right ventricular hypertrophy in MCT-PAH by targeting TGF-ß1/smad2/3 signaling. These findings suggest that miR-663 may represent as an attractive approach for the diagnosis and treatment for PAH.


Assuntos
MicroRNAs/sangue , Hipertensão Arterial Pulmonar/genética , Fator de Crescimento Transformador beta1/metabolismo , Remodelação Vascular/genética , Idoso , Animais , Becaplermina/farmacologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Monocrotalina/toxicidade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Hipertensão Arterial Pulmonar/induzido quimicamente , Hipertensão Arterial Pulmonar/metabolismo , Artéria Pulmonar/citologia , Ratos Sprague-Dawley , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/genética , Remodelação Vascular/efeitos dos fármacos
5.
Opt Lett ; 46(11): 2758-2761, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061106

RESUMO

In general, a spin-polarized light beam cannot couple its spin angular momentum (SAM) with intrinsic orbital angular momentum (IOAM) without spin reversal. Here we find that nonlinear media can give the spin-polarized photon an IOAM, as they travel in the media due to the nonlinear susceptibility along the transmission direction, which does not require spin reversal. To characterize this SAM-to-IOAM conversion process, we establish an evolution ray equation for photons carrying IOAM by reference to the Schrödinger equation. We further reveal the inherent physics of such a phenomenon from a full-wave perspective and find that the vortex generation originates from the nonlinear-induced geometric phase.

6.
Int Heart J ; 62(4): 786-791, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34276021

RESUMO

Asymptomatic recurrences of atrial fibrillation (AF) have been found to be common after ablation.A randomized controlled trial of AF screening using a handheld single-lead ECG monitor (BigThumb®) or a traditional follow-up strategy was conducted in patients with non-valvular AF after catheter ablation. Consecutive patients were randomized to either BigThumb Group (BT Group) or Traditional Follow-up Group (TF Group). The ECGs collected via BigThumb were compared using the automated AF detection algorithm, artificial intelligence (AI) algorithm, and cardiologists' manual review. Subsequent changes in adherence to oral anticoagulation of patients were also recorded. In this study, we examined 218 patients (109 in each group). After a follow-up of 345.4 ± 60.2 days, AF-free survival rate was 64.2% in BT Group and 78.9% in TF Group (P = 0.0163), with more adherence to oral anticoagulation in BT Group (P = 0.0052). The participants in the BT Group recorded 26133 ECGs, among which 3299 (12.6%) were diagnosed as AF by cardiologists' manual review. The sensitivity and specificity of the AI algorithm were 94.4% and 98.5% respectively, which are significantly higher than the automated AF detection algorithm (90.7% and 96.2%).As per our findings, it was determined that follow-up after AF ablation using BigThumb leads to a more frequent detection of AF recurrence and more adherence to oral anticoagulation. AI algorithm improves the accuracy of ECG diagnosis and has the potential to reduce the manual review.


Assuntos
Assistência ao Convalescente/métodos , Fibrilação Atrial/diagnóstico , Ablação por Cateter , Eletrocardiografia Ambulatorial , Idoso , Fibrilação Atrial/cirurgia , Feminino , Humanos , Masculino
7.
Opt Express ; 28(10): 15601-15610, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403584

RESUMO

Manipulating circularly polarized (CP) light waves at will are highly important for photonic researches and applications. Recently, while Pancharatnam-Berry (PB) metasurfaces have shown unprecedented capabilities to control CP light, meta-devices constructed so far always suffer from the limitations of low-efficiency and narrow bandwidth. Here, we propose a scheme to construct PB metasurfaces with these two issues well addressed. To verify our idea, two PB meta-devices are designed and fabricated for achieving high-efficiency and broadband photonic spin Hall effect and focusing effect, respectively. Experimental results, in good agreement with full wave simulations, demonstrate the desired functionalities with efficiencies reaching 80% within an ultra-wide frequency band (8.2-17.3GHz). The proposed design scheme is generic and can be extended to high-frequency regimes. Our work can stimulate the realizations of high-performance and broadband PB meta-devices with diversified functionalities.

8.
Eur J Clin Invest ; 50(11): e13308, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32663314

RESUMO

OBJECTIVE: For differentiating heart failure (HF) with preserved ejection fraction (HFpEF) from HF with reduced EF (HFrEF), N-terminal prohormone brain natriuretic peptide (NT-proBNP) is less accurate. Decreased expression of microRNA-19b (miR-19b) is associated with increased cardiac-fibrosis. We aim to evaluate the value of miR-19b in diagnosing HFrEF patients. METHOD: We included 200 HF patients and 100 healthy controls. Intergroup comparisons of miR-19b were made and correlation between miR-19b and NT-proBNP was analysed. Diagnostic values of NT-proBNP and miR-19b for HF patients versus controls and HFrEF versus HFpEF were obtained by ROC analysis and described by area under curve (AUC), sensitivity and specificity. RESULTS: HFrEF patients (0.87, 95% CI 0.37-1.45) had significantly lower miR-19b level than HFpEF group (1.32, 95% CI 0.63-2.51) and the controls (1.82, 95% CI 0.37-1.45) (both P < .001). There was a remarkable negative correlation between miR-19b and NT-proBNP (P < .001). The additional use of miR-19b did not improve the accuracy of NT-proBNP alone in diagnosing HF patients from the controls (both AUC = 0.98, 95%CI 0.97-0.99). However, as for distinguishing the HFpEF from HFrEF, miR-19b and NT-proBNP yielded a significantly higher AUC than NT-proBNP alone (0.85, 95% CI 0.80-0.90 vs. 0.66, 95% CI 0.58-0.74) (P < .001), and the sensitivity for diagnosing HFrEF was raised from 58% to 77% and the specificity from 75% to 79%. CONCLUSIONS: On top of NT-proBNP, miR-19b added the value in diagnosing HFrEF. But in view of satisfactory accuracy of NT-proBNP in predicting HF from the healthy volunteers, miR-19b did not provide incremental value.


Assuntos
MicroRNA Circulante/sangue , Insuficiência Cardíaca/sangue , MicroRNAs/sangue , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Volume Sistólico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
9.
Opt Lett ; 45(15): 4140-4143, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735243

RESUMO

Transition metal dichalcogenides (TMDs) promise advanced optoelectronic applications thanks to their visible or near-infrared and layer-dependent bandgaps. Even more exciting phenomena happen via stacking the TMDs to form the vertical heterostructures, such as the exotic interlayer excitons in atomically rearranged bilayer TMDs, as the result of the tunable interlayer hopping of two monolayers. So far, those literature studies focus on either two-dimensional (2D) TMDs or the layered bulky three-dimensional (3D) TMDs. The mixed-dimensional TMDs remain a fundamental yet not fully appreciated curiosity. In this Letter, we have theoretically and numerically investigated the exciton polaritons in such a hybrid system composed by the nanostructured layered (3D) and monolayer (2D) TMDs. The strong coupling has been observed of the lattice mode in high index patterned 3D TMDs and exciton from the direct bandgaps of the 2D TMDs, with the tunable Rabi splitting by geometrically shaping the 3D TMDs. We believe that our mixed-dimensional system with the novel stacks of 2D/3D van der Waals heterostructures may allow for controlling the exciton transport for advanced quantum, polaritonic, and optoelectronic devices.

10.
Opt Express ; 26(9): 11728-11736, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29716091

RESUMO

Electromagnetic (EM) wave absorption plays a vital role in photonics. While metasurfaces are proposed to absorb EM waves efficiently, most of them exhibit limited bandwidth and fixed functionalities. Here, we propose a broadband and tunable terahertz (THz) absorber based on a graphene-based metasurface, which is constructed by a single layer of closely patterned graphene concentric double rings and a metallic mirror separated by an ultrathin SiO2 layer. Plasmonic hybridization between two graphene rings significantly enlarges the absorption bandwidth, which can be further tuned by gating the graphene. Moreover, the specific design also makes our device insensitive to the incident angle and polarization state of impinging EM waves. Our results may inspire certain wave-modulation-related applications, such as THz imaging, smart absorber, tunable sensor, etc.

11.
Biomed Chromatogr ; 30(4): 566-73, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26268650

RESUMO

The core-shell structure Fe3 O4 /SiO2 magnetic microspheres were prepared by a sol-gel method, and immobiled with iminodiacetic acid (IDA) as metal ion affinity ligands for protein adsorption. The size, morphology, magnetic properties and surface modification of magnetic silica nanospheres were characterized by various modern analytical instruments. It was shown that the magnetic silica nanospheres exhibited superparamagnetism with saturation magnetization values of up to 58.1 emu/g. Three divalent metal ions, Cu(2+) , Ni(2+) and Zn(2+) , were chelated on the Fe3 O4 @SiO2 -IDA magnetic microspheres to adsorb lysozyme. The results indicated that Ni(2+) -chelating magnetic microspheres had the maximum adsorption capacity for lysozyme of 51.0 mg/g, adsorption equilibrium could be achieved within 60 min and the adsorbed protein could be easily eluted. Furthermore, the synthesized Fe3 O4 @SiO2 -IDA-Ni(2+) magnetic microspheres were successfully applied for selective enrichment lysozyme from egg white and His-tag recombinant Homer 1a from the inclusion extraction expressed in Escherichia coli. The result indicated that the magnetic microspheres showed unique characteristics of high selective separation behavior of protein mixture, low nonspecific adsorption, and easy handling. This demonstrates that the magnetic silica microspheres can be used efficiently in protein separation or purification and show great potential in the pretreatment of the biological sample.


Assuntos
Cromatografia de Afinidade/métodos , Histidina/isolamento & purificação , Iminoácidos/química , Nanopartículas de Magnetita/química , Muramidase/isolamento & purificação , Dióxido de Silício/química , Adsorção , Animais , Proteínas de Transporte/química , Proteínas de Transporte/isolamento & purificação , Galinhas , Histidina/química , Proteínas de Arcabouço Homer , Muramidase/química , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
12.
Opt Express ; 22(16): 19108-16, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25320997

RESUMO

A kind of magnetic field sensor composed of magnetic fluid surrounding a segment of singlemode fiber is proposed. The taper-like and lateral-offset fusion splicing techniques are employed. The sensing principle is based on cladding mode interference. The interference valley wavelength or transmission loss of the sensing structure is sensitive to the external magnetic field, which is utilized for magnetic field sensing. The linear response regions are obtained in the range of 38-225 Oe and 250-475 Oe. For the valley-wavelength-shift-type sensing, the sensitivities are 14.1 pm/Oe and 26 pm/Oe at low and high field ranges, respectively. For the transmission-loss-variation-type sensing, the sensitivity of -0.024 dB/Oe is achieved for the magnetic field strength ranging from 250 to 475 Oe.

13.
Biomed Chromatogr ; 28(6): 907-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24861763

RESUMO

Molecular imprinting as a promising and facile separation technique has received much attention because of its high selectivity for target molecules. In this study, lysozyme molecularly imprinted polymers (Lys-MIPs) were successfully prepared by the entrapment method with lysozyme as the template molecule, acrylamide as the functional monomer and N,N-methylenebisacrylamide as the cross-linker. The removal of the template lysozyme from the molecularly imprinted polymers was investigated in detail by two methods. The synthesized Lys-MIPs were characterized by scanning electron microscopy and Fourier transform-infrared, and the adsorption capacity, selectivity and reproducibility of the Lys-MIPs were also evaluated. The maximum adsorption capacity reached 94.8 mg/g, which is twice that of nonmolecularly imprinted polymers, and satisfactory selectivity and reproducibility were achieved. Using the Lys-MIP column, lysozyme could be separated completely from egg white, with purity close to 100% and mass recovery of 98.2%. This illustrated that the synthesized Lys-MIPs had high specific recognition and selectivity to the template lysozyme when they were applied to a mixture of protein standards and a real sample.


Assuntos
Clara de Ovo/química , Muramidase/isolamento & purificação , Polímeros/química , Adsorção , Animais , Galinhas , Impressão Molecular , Muramidase/química , Polímeros/síntese química
14.
Sensors (Basel) ; 14(10): 19086-94, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25317761

RESUMO

Magnetic field sensing based on magnetic-fluid-clad multimode-singlemode- multimode fiber structures is proposed and experimentalized. The structures are fabricated out using fiber fusion splicing techniques. The sensing principle is based on the interference between the core mode and cladding modes. Two interference dips are observed in our spectral range. Experimental results indicate that the magnetic field sensing sensitivities of 215 pm/mT and 0.5742 dB/mT are obtained for interference dip around 1595 nm. For interference dip around 1565 nm, the sensitivities are 60.5 pm/mT and 0.4821 dB/mT. The response of temperature is also investigated. The temperature sensitivity for the dip around 1595 nm is obtained to be 9.93 pm/°C.

15.
Heliyon ; 10(3): e25187, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333816

RESUMO

Once the oil pipeline leakage accident occurs on the river, the simulation of the leakage diffusion range is of great significance for the designation of emergency rescue plans. The existing methods cannot show the precise leakage diffusion process consistent with the physical law for crude oil on the river and the simulation suffers high run-time complexity. This paper proposed a two-phase leakage simulation for oil and water combined with the physical process of smoothed particle hydrodynamics (SPH) and graph attention network. A new and efficient method-Mixture Tension Divergence-Free SPH (MTDF-SPH)-that the mixture model and the surface tension model are introduced to the divergence-free smoothed particle hydrodynamics (DFSPH) for simulating the mixing and decomposition effects of immiscible phases. To further accelerate the leakage diffusion process, we design a physics-aware heterogeneous graph attention network (PAGATNet), based on Attention Graph Network Block (AGNB) and Feature-Response Knowledge Distillation (FRKD) to enhance the network's ability for extracting the particle features of physical properties. The experimental results on different test cases show the accuracy, robustness and effectiveness of our method than those of the state-of-the-art in two-phase leakage simulation of crude oil on the river.

16.
Ann Saudi Med ; 44(3): 167-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38853475

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS), which results in lung injury as a consequence of sepsis and septic shock, is associated with severe systemic inflammation and is responsible for a high worldwide mortality rate. OBJECTIVE: Investigate whether corticosteroids could benefit clinical outcomes in adult with ARDS. METHODS: A comprehensive search of electronic databases Ovid MEDLINE, Ovid EMbase, and Cochrane Library from their inception to 7 May 2023 was conducted to identify studies that met the eligibility criteria, including only randomized controlled trials. The study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the methods of trial sequential analysis. MAIN OUTCOME MEASURES: Mortality rates, including including the 14-, 28-, 45-, and 60-day mortality, hospital mortality, and intensive care unit (ICU) mortality. SAMPLE SIZE: 17 studies with 2508 patients. RESULTS: Data relating to mortality at 14, 28, 45, and 60 days were not significantly different when treatments with corticosteroids and placebo were compared. In terms of hospital and ICU mortality, the mortality of those who had received corticosteroids was significantly lower than that of those who had not. ARDS patients who received assisted ventilation benefited from corticosteroid therapy, as revealed by the significant difference in outcome days between those who received assisted ventilation and those who did not. Corticosteroid had significantly more days free from mechanical ventilation, ICU-free days, and MODS-free days during the first 28 days, but not more organ support-free days up to day 28. CONCLUSION: Although corticosteroid therapy did not reduce mortality rates at different observation periods, it significantly reduced hospital and ICU mortality. Administering corticosteroids to ARDS patients significantly decreased the days of assisted ventilation and time cost consumption. This study confirmed that long-term use of low-dose glucocorticoids may have a positive effect on early ARDS. LIMITATION: Risk of bias due to the differences in patient characteristics.


Assuntos
Corticosteroides , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Respiração Artificial , Síndrome do Desconforto Respiratório , Adulto , Humanos , Corticosteroides/administração & dosagem , Unidades de Terapia Intensiva/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial/estatística & dados numéricos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/etiologia , Resultado do Tratamento
17.
Nanoscale Adv ; 6(2): 559-569, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38235083

RESUMO

Optoelectronic synaptic transistors are attractive for applications in next-generation brain-like computation systems, especially for their visible-light operation and in-sensor computing capabilities. However, from a material perspective, it is difficult to build a device that meets expectations in terms of both its functions and power consumption, prompting the call for greater innovation in materials and device construction. In this study, we innovatively combined a novel perovskite carrier supply layer with an Al/MoO3 interface carrier regulatory layer to fabricate optoelectronic synaptic devices, namely Al/MoO3/CsFAMA/ITO transistors. The device could mimic a variety of biological synaptic functions and required ultralow-power consumption during operation with an ultrafast speed of >0.1 µs under an optical stimulus of about 3 fJ, which is equivalent to biological synapses. Moreover, Pavlovian conditioning and visual perception tasks could be implemented using the spike-number-dependent plasticity (SNDP) and spike-rate-dependent plasticity (SRDP). This study suggests that the proposed CsFAMA synapse with an Al/MoO3 interface has the potential for ultralow-power neuromorphic information processing.

18.
Cardiovasc Res ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900927

RESUMO

AIMS: MicroRNA-126 (miR-126), one of the most abundant microRNAs in platelets, is involved in the regulation of platelet activity and the circulating miR-126 is reduced during antiplatelet therapy. However, whether intraplatelet miR-126 plays a role in thrombosis and platelet inhibition remains unclear. METHODS AND RESULTS: Here, using tissue-specific knockout mice, we reported that the deficiency of miR-126 in platelets and vascular endothelial cells significantly prevented thrombosis and prolonged bleeding time. Using chimeric mice, we identified that the lack of intraplatelet miR-126 significantly prevented thrombosis. Ex vivo experiments further demonstrated that miR-126-deficient platelets displayed impaired platelet aggregation, spreading and secretory functions. Next, miR-126 was confirmed to target phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2) in platelet, which encodes a negative regulator of the PI3 K/AKT pathway, enhancing platelet activation through activating the integrin αIIbß3-mediated outside-in signaling. After undergoing myocardial infarction (MI), chimeric mice lacking intraplatelet miR-126 displayed reduced microvascular obstruction and prevented MI expansion in vivo. In contrast, overexpression of miR-126 by the administration of miR-126 agonist (agomiR-126) in wild-type mice aggravated microvascular obstruction and promoted MI expansion, which can be almost abolished by aspirin administration. In patients with cardiovascular diseases, antiplatelet therapies, either aspirin alone or combined with clopidogrel, decreased the level of intraplatelet miR-126. The reduction of intraplatelet miR-126 level was associated with the decrease of platelet activity. CONCLUSIONS: Our murine and human data reveal that (i) intraplatelet miR-126 contributes to platelet activity and promotes thrombus formation, and (ii) the reduction of intraplatelet miR-126 contributes to platelet inhibition during antiplatelet therapy.

19.
Opt Lett ; 38(19): 3765-8, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24081047

RESUMO

Magnetic field sensing based on magnetic fluid (MF) and a singlemode-multimode-singlemode (SMS) fiber structure is proposed. The sensitivity of the proposed sensing system can be enhanced by corroding the cladding of the multimode fiber of the SMS fiber structure. The achieved maximum magnetic field sensitivity of our experimental structures is -16.86 pm/Oe as the fiber is corroded for 1680 s. The visibility of the interference dip for the MF-clad SMS fiber structure decreases with corrosion time. Considering the trade-off between sensitivity and visibility, the figure of merit of the sensing system is employed to evaluate the sensing performance comprehensively. In our experiments, the structure corroded for ~1620 s is found to have maximum sensing performance.

20.
Sci Data ; 10(1): 563, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620343

RESUMO

Crude oil pipelines are considered as the lifelines of energy industry. However, accidents of the pipelines can lead to severe public health and environmental concerns, in which greenhouse gas (GHG) emissions, primarily methane, are frequently overlooked. While previous studies examined fugitive emissions in normal operation of crude oil pipelines, emissions resulting from accidents were typically managed separately and were therefore not included in the emission account of oil systems. To bridge this knowledge gap, we employed a bottom-up approach to conducted the first-ever inventory of GHG emissions resulting from crude oil pipeline accidents in the United States at the state level from 1968 to 2020, and leveraged Monte Carlo simulation to estimate the associated uncertainties. Our results reveal that GHG emissions from accidents in gathering pipelines (~720,000 tCO2e) exceed those from transmission pipelines (~290,000 tCO2e), although significantly more accidents have occurred in transmission pipelines (6883 cases) than gathering pipelines (773 cases). Texas accounted for over 40% of total accident-related GHG emissions nationwide. Our study contributes to enhanced accuracy of the GHG account associated with crude oil transport and implementing the data-driven climate mitigation strategies.

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