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1.
Microcirculation ; 31(3): e12851, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495025

RESUMO

BACKGROUND AND OBJECTIVES: Chest pain is a relatively long-term symptom that commonly occurs in patients who have contracted COVID-19. The reasons for these symptoms remain unclear, with coronary microvascular dysfunction (CMD) emerging as a potential factor. This study aimed to assess the presence of CMD in these patients by measuring the angio-derived index of microcirculatory resistance (AMR). METHODS: In this cross-sectional case-control study, patients who had chest pain and a history of COVID-19 infection within the preceding 30 to 60 days were included. The control subjects were patients without COVID-19. Demographic, clinical, and echocardiographic data were recorded. Angiographic images were collected for AMR analysis through an angioplus quantitative flow ratio measurement system. Propensity score matching (PSM) was performed to match the two groups. Multivariate logistic regression was used to examine the association between COVID-19 incidence and the increase in AMR (AMR > 285 mmHg*s/m) after correction for other confounders. RESULTS: After PSM, there were 58 patients in each group (the mean age was 66.3 ± 9.04 years, and 55.2% were men). The average time between the onset of COVID-19 infection and patient presentation at the hospital for coronary angiography was 41 ± 9.5 days. Moreover, there was no significant difference in the quantitative flow ratio between the two groups. Patients with COVID-19 had a greater mean AMR (295 vs. 266, p = 0.002). Multivariate logistic regression analysis revealed that COVID-19 (OR = 3.32, 95% CI = 1.50-7.60, p = 0.004) was significantly associated with an increase in AMR. CONCLUSIONS: Long-term COVID-19 patients who experience chest pain without evidence of myocardial ischemia exhibit an increase in AMR, and CMD may be one of the reasons for this increase. COVID-19 is an independent risk factor for an increase in AMR.


Assuntos
COVID-19 , Isquemia Miocárdica , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Estudos de Casos e Controles , Microcirculação , Estudos Transversais , Angiografia Coronária/métodos , Dor no Peito
2.
Sci Data ; 10(1): 649, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739952

RESUMO

Human body expressions convey emotional shifts and intentions of action and, in some cases, are even more effective than other emotion models. Despite many datasets of body expressions incorporating motion capture available, there is a lack of more widely distributed datasets regarding naturalized body expressions based on the 2D video. In this paper, therefore, we report the multi-view emotional expressions dataset (MEED) using 2D pose estimation. Twenty-two actors presented six emotional (anger, disgust, fear, happiness, sadness, surprise) and neutral body movements from three viewpoints (left, front, right). A total of 4102 videos were captured. The MEED consists of the corresponding pose estimation results (i.e., 397,809 PNG files and 397,809 JSON files). The size of MEED exceeds 150 GB. We believe this dataset will benefit the research in various fields, including affective computing, human-computer interaction, social neuroscience, and psychiatry.


Assuntos
Ira , Emoções , Humanos , Medo , Movimento (Física) , Tristeza
3.
Nanomaterials (Basel) ; 13(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37630904

RESUMO

Solar-driven interfacial evaporation and purification is a promising solar energy conversion technology to produce clean water or solve water scarcity. Although wood-based photothermal materials have attracted particular interest in solar water purification and desalination due to their rapid water supply and great heat localization, challenges exist given their complicated processing methods and relatively poor stability. Herein, we propose a facile approach for fabricating a bilayered wood-poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (wood-PEDOT:PSS) hydrogel interfacial evaporator by direct drop-casting and dry-annealing. Benefiting from the unique combined merits of the wood-PEDOT:PSS hydrogel evaporator, i.e., excellent light absorption (~99.9%) and efficient photothermal conversion of nanofibrous PEDOT:PSS and the strong hydrophilicity and fast water transport from wood, the as-fabricated bilayered wood-PEDOT:PSS hydrogel evaporator demonstrates a remarkably high evaporation rate (~1.47 kg m-2 h-1) and high energy efficiency (~75.76%) at 1 kW m-2. We further demonstrate the practical applications of such an evaporator for sewage purification and desalination, showing outstanding performance stability and partial salt barrier capability against a continuous 10-day test in simulated seawater and an ultrahigh ion removal rate of 99.9% for metal ion-containing sewage. The design and fabrication of such novel, efficient wood-based interfacial evaporators pave the way for large-scale applications in solar water purification.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36498080

RESUMO

In the post-epidemic era, regular epidemic prevention and control is a daunting and ongoing task for nations all around the world. University halls of residence have been important spaces where university students balance their studies, work, and personal lives after COVID-19. Therefore, a healthy physical living environment deserves more attention. This paper compares situations before and after COVID-19 in an effort to evaluate the impact of indoor environments in university halls of residence on students. The study proposed eight vital dimensions for creating a healthy university hall of residence environment and, from 14 September to 4 October 2022, used an online questionnaire to collect data from 301 university students studying in Zhejiang, China. The key quality of service characteristics for fostering a healthy environment in university halls of residence were discovered using descriptive statistical analysis and revised importance-performance analysis (IPA). We found that an improved indoor physical environment and efficient arrangement of indoor space were crucial for the health of university students. The quality of educational services could be improved, and indoor exercise should be utilized effectively, both of which can contribute significantly to a healthy indoor environment. This study aims to contribute to the development of future initiatives to support healthy physical living environments in university halls of residence.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Universidades , Habitação , Estudantes , China/epidemiologia
5.
Rev Sci Instrum ; 93(10): 103545, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319342

RESUMO

Here, we describe a flat-field-response, four-channel x-ray imaging instrument developed to study hotspot asymmetries in inertial-confinement fusion experiments. We discuss the details of its design and optical characterization, the diagnostic deployment of the device, and experiments with it. We achieved a spatial-response flatness better than ∼8.4% within a ±200 µm field of view (FOV), with a spatial resolution of ∼4 µm at the center of the FOV. We used the system to characterize the low-order asymmetry of the implosion hotspot, and we obtained improved results after adjustments to improve the irradiation symmetry. Due to the flat-field-response characteristic, the versatile instrument also has the potential to be applied to diagnostics for the hotspot electron temperature and the Rayleigh-Taylor instability.

7.
Opt Express ; 30(15): 26761-26773, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236862

RESUMO

High-resolution X-ray imaging diagnosis is a critical method for measuring Rayleigh-Taylor instability growth and hot spot interface morphology in inertial confinement fusion experiments. In this study, we develop a quasi-monochromatic elliptical Kirkpatrick-Baez microscope based on aberration theory, breaking the aberration limit of conventional Kirkpatrick-Baez microscopes. The microscope was characterized in the laboratory for spatial resolution performance and modulation transfer function before being implemented in cavity experiments at the SG-III prototype laser facility. The results demonstrate that the edge-based method achieves a spatial resolution of <2 µm in the central field of view and modulation of 800 lp/mm spatial frequency of >20%.

8.
Rev Sci Instrum ; 93(9): 093526, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182515

RESUMO

High-precision x-ray imaging diagnostics of hotspot at the stagnation stage are essential for regulating implosion asymmetry and retrieving physical implosion parameters. With regard to 10-20 keV energy band imaging, existing diagnostic instruments such as Kirkpatrick-Baez microscopes and pinhole cameras are insufficient in terms of spatial resolution and collection efficiency. The situation is even worse when high-speed, time-resolved imaging diagnostics are performed by coupling framing cameras or line-of-sight imagers. This article presents the basic principles and optical system design of a 17.48 keV modified Wolter x-ray microscope, to resolve the problems encountered in high-energy imaging diagnostics. The proposed optical configuration offers a better spatial resolution, greater depth of field, and preliminary compliance with the requirements of high precision optical processing techniques. The spatial resolution is better than 1 µm in a field range ±150 µm, and is better than 3 µm in a total field of view ∼408 µm in diameter. The geometric solid angle is calculated as 3.0 × 10-5 sr and is estimated to be 1.2 × 10-6 sr, considering the reflectivity of the double mirrors. The proposed microscope is expected to effectively improve spatial resolution and signal-to-noise ratio for high-energy imaging diagnostics.

9.
Comput Math Methods Med ; 2022: 8979404, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281945

RESUMO

The objective of this study was to analyze the value of artificial intelligence algorithm-based computerized tomography (CT) image combined with serum tumor markers for diagnoses of pancreatic cancer. In the study, 68 hospitalized patients with pancreatic cancer were selected as the experimental group, and 68 hospitalized patients with chronic pancreatitis were selected as the control group, all underwent CT imaging. An image segmentation algorithm on account of two-dimensional (2D)-three-dimensional (3D) convolution neural network (CNN) was proposed. It also introduced full convolutional network (FCN) and UNet network algorithm. The diagnostic performance of CT, serum carbohydrate antigen-50 (CA-50), serum carbohydrate antigen-199 (CA-199), serum carbohydrate antigen-242 (CA-242), combined detection of tumor markers, and CT-combined tumor marker testing (CT-STUM) for pancreatic cancer were compared and analyzed. The results showed that the average Dice coefficient of 2D-3D training was 84.27%, which was higher than that of 2D and 3D CNNs. During the test, the maximum and average Dice coefficient of the 2D-3D CNN algorithm was 90.75% and 84.32%, respectively, which were higher than the other two algorithms, and the differences were statistically significant (P < 0.05). The penetration ratio of pancreatic duct in the experimental group was lower than that in the control group, the rest were higher than that in the control group, and the differences were statistically significant (P < 0.05). CA-50, CA-199, and CA-242 in the experimental group were 141.72 U/mL, 1548.24 U/mL, and 83.65 U/mL, respectively, which were higher than those in the control group, and the differences were statistically significant (P < 0.05). The sensitivity, specificity, positive predictive value, and authenticity of combined detection of serum tumor markers were higher than those of CA-50, CA-199, and CA-242, and the differences were statistically significant (P < 0.05). The results showed that the proposed algorithm 2D-3D CNN had good stability and image segmentation performance. CT-STUM had high sensitivity and specificity in diagnoses of pancreatic cancer.


Assuntos
Algoritmos , Biomarcadores Tumorais/sangue , Tomografia Computadorizada Multidetectores/estatística & dados numéricos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Antígenos Glicosídicos Associados a Tumores/sangue , Inteligência Artificial , Estudos de Casos e Controles , Biologia Computacional , Feminino , Humanos , Imageamento Tridimensional/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Pancreatite Crônica/sangue , Pancreatite Crônica/diagnóstico por imagem , Sensibilidade e Especificidade
10.
Opt Express ; 30(6): 8777-8793, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299323

RESUMO

The measurement of hotspot electron temperature is a paramount technique of implosion physics research in inertial confinement fusion. This study proposes a novel quasi-coaxis dual-energy flat spectral response high-resolution X-ray imaging instrument comprising a dual-channel total-reflection Kirkpatrick-Baez microscope and two flat non-periodic multilayer mirrors, which can image at 6.4 ± 0.5 and 9.67 ± 0.5 keV simultaneously. Various theoretical simulations were performed to verify the performance and feasibility of the imaging instrument, which was assembled and characterized in a laboratory. Experimental results show that the imaging instrument could achieve a high spatial resolution of 5 µm in a ± 150 µm field of view (FOV), the root mean square(RMS) deviation values of the measured reflection efficiency are 1.71% and 1.82% for the 6.4 keV and 9.67 keV imaging channels, respectively, in the ± 150 µm FOV.

11.
J Interv Cardiol ; 2022: 6361398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185397

RESUMO

OBJECTIVE: To evaluate the correlation between the TIMI frame count, IMR, and CFR in coronary microvascular disease (slow flow phenomenon). METHODS: TFC and IMR were recorded in the nitroglycerin and ATP administration states, and the relationship between TFC, IMR, and CFR in specific states was analyzed. RESULTS: A total of 41 patients with baseline TFC >25 frames on coronary angiography were enrolled, and nitroglycerin reduced TFC by 50% from baseline in 24 (58.54%) patients; 16 of the remaining 17 patients were able to achieve a 50% reduction in TFC by further intracoronary ATP injection. 10 patients were further tested for IMR, and the results showed significant correlations between baseline TFC and IMR (r = 0.775, P=0.008), TFC and IMR after nitroglycerin (r = 0.875, P=0.001), and the minimal TFC and IMR that could be obtained with nitroglycerin or ATP administration (r = 0.890, P=0.001). There was also a significant correlation between the proportional improvement in TFC and CFR before and after nitroglycerin injection (r = 0.685, P=0.029). In addition, we observed a lower IMR measured after nitroglycerin than after ATP in three patients, suggesting that CMD may be dominated by NO-sensitive vascular such as prearterioles and that an extensive analysis of the target site of CMD may be achieved by stepwise drug administration. CONCLUSION: Induction of TFC in different states by a stepwise drug approach may serve as a potential primary screening method for coronary microcirculatory dysfunction, thereby reducing the need for further IMR or CFR testing.


Assuntos
Nitroglicerina , Fenômeno de não Refluxo , Angiografia Coronária , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Humanos , Microcirculação , Nitroglicerina/uso terapêutico
12.
Polymers (Basel) ; 15(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36616440

RESUMO

Flexible strain sensor as a measurement tool plays a significant role in agricultural development by long-term stable monitoring of the dynamic progress of plant growth. However, existing strain sensors still suffer from severe drawbacks, such as large hysteresis, insufficient fatigue resistance, and inferior stability, limiting their broad applications in the long-term monitoring of plant growth. Herein, we fabricate a novel conductive hydrogel strain sensor which is achieved through uniformly dispersing the conductive activated charcoal (AC) in high-viscosity polyvinyl alcohol (PVA) solution forming a continuous conductive network and simple preparation by freezing-thawing. The as-prepared strain sensor demonstrates low hysteresis (<1.5%), fatigue resistance (fatigue threshold of 40.87 J m−2), and long-term sensing stability upon mechanical cycling. We further exhibit the integration and application of PVA-AC strain sensor to monitor the growth of plants for 14 days. This work may offer an effective strategy for monitoring plant growth with conductive hydrogel strain sensor, facilitating the advancement of agriculture.

14.
Sci Rep ; 8(1): 9971, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29967472

RESUMO

The collimation of a thermal atomic ytterbium beam utilizing a two-dimensional optical molasses is analysed by employing the Monte Carlo simulation. The dependencies of the collimation efficiency on power, frequency detuning and beam size of the laser are studied for various conditions, especially for the case of an imbalanced laser intensity and an impure laser polarization. The influences of these imperfect factors are discussed, and the lowest transverse temperature by the collimation in the experiment is evaluated.

15.
Sci Rep ; 8(1): 8022, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29789631

RESUMO

Optical clocks are the most precise measurement devices. Here we experimentally characterize one such clock based on the 1S0-3P0 transition of neutral 171Yb atoms confined in an optical lattice. Given that the systematic evaluation using an interleaved stabilization scheme is unable to avoid noise from the clock laser, synchronous comparisons against a second 171Yb lattice system were implemented to accelerate the evaluation. The fractional instability of one clock falls below 4 × 10-17 after an averaging over a time of 5,000 seconds. The systematic frequency shifts were corrected with a total uncertainty of 1.7 × 10-16. The lattice polarizability shift currently contributes the largest source. This work paves the way to measuring the absolute clock transition frequency relative to the primary Cs standard or against the International System of Units (SI) second.

16.
Sci Rep ; 8(1): 7927, 2018 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-29784962

RESUMO

The ultracold atomic gas serving as the quantum reference is a key part of an optical lattice clock, and the temperature of atoms in the optical lattice affects the uncertainty and instability of the optical lattice clocks. Since the carrier spectrum of the clock transition in the lattices reflects the thermal dynamics of cold atoms, the temperature of atoms can be extracted from the carrier spectrum in a non-magic wavelength lattice of ytterbium optical clocks. Furthermore, the temperatures obtained from the carrier spectra are in good agreement with the results obtained by the time-of-flight method and thermometry based on the sideband spectrum. In addition, the heating effects caused by the lattice laser are studied on the basis of the sample temperatures.

17.
Eur Heart J Qual Care Clin Outcomes ; 4(3): 208-219, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29726987

RESUMO

Aims: We previously showed in patients with ST-segment elevated myocardial infarction (STEMI) that admission levels of macrophage migration inhibitory factor (MIF) predict infarct size. We studied whether admission MIF alone or in combination with other biomarkers is useful for risk assessment of acute and chronic clinical outcomes in STEMI patients. Methods and results: A total of 658 STEMI patients treated with primary percutaneous coronary intervention (PCI) were consecutively recruited. MIF level was determined at admission and echocardiography performed on day-3 and then 12 months post-MI. Patients were followed for a median period of 64 months. Major endpoints included ST-segment resolution, all-cause mortality, and major adverse cardiovascular events (MACE). High MIF level was associated with larger enzymatic infarct size, incomplete resolution of ST-segment elevation post-PCI, impaired left ventricular ejection fraction (LVEF), and poorer improvement of LVEF (all P < 0.001). After adjustment for classical risk factors standard biomarkers and day-3 LVEF, admission MIF remained independently prognostic for all-cause mortality [hazard ratio (HR) 2.27, 95% confidence interval (CI) 1.43-3.22], and MACE (HR 1.39, 95% CI 1.12-1.71, both P < 0.05). MIF was a significant additive predictor of all-cause mortality with a net reclassification improvement of 0.34 (P = 0.02). Furthermore, patients in high tertile of both admission MIF and day-3 Nt-proBNP had the highest mortality risk relative to other tertile groups (HR 11.28, 95% CI 4.82-26.94; P < 0.001). Conclusion: STEMI patients with high admission MIF level experienced a poorer recovery of cardiac function and worse long-term adverse outcomes. Combination of Nt-proBNP with MIF further improves prognostic capability.


Assuntos
Oxirredutases Intramoleculares/sangue , Fatores Inibidores da Migração de Macrófagos/sangue , Admissão do Paciente , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Biomarcadores/sangue , Causas de Morte/tendências , China/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Taxa de Sobrevida/tendências , Fatores de Tempo
18.
Am J Med Sci ; 355(4): 307-313, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29661343

RESUMO

BACKGROUND: Reduced forced expiratory volume in 1 second percentage (FEV1%) predicted is closely related to cardiovascular mortality. However, evidence regarding the correlation between FEV1% predicted and the severity of coronary atherosclerosis observed on coronary angiography is still limited. We aimed to explore whether a decline in FEV1% predicted was associated with diffuse coronary atherosclerosis in hospitalized patients. METHODS: A cross-sectional study enrolling hospitalized patients with cardiovascular symptoms undergoing both coronary angiography and lung function testing was conducted. The correlation between FEV1% predicted and angiographic characteristics, including the number of diseased vessels, total number of coronary lesions and Gensini score was analyzed. RESULTS: Eighty-five patients were included. Patients with ≥2-vessel disease had significantly lower FEV1% predicted than patients with <2-vessel disease (60.9% ± 19.7% versus 77.2% ± 19.7%, P < 0.001). FEV1% predicted was inversely related to the total number of coronary lesions (ß = -0.029, P = 0.002) and Gensini score (ß = -0.525, P = 0.006). FEV1% predicted was independently associated with ≥2-vessel disease (odds ratio = 0.961, P = 0.007), total number of coronary lesions (adjusted ß = -0.039, P < 0.001) and Gensini score (adjusted ß = -0.602, P = 0.005) after adjustment for other traditional cardiovascular risk factors. In the coronary artery disease subgroup, FEV1% predicted maintained an independent and negative relationship with ≥2-vessel disease, total number of coronary lesions and Gensini score. CONCLUSIONS: Reduced FEV1% predicted was closely associated with multivessel coronary disease and diffuse coronary atherosclerosis in hospitalized patients undergoing coronary angiography.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Volume Expiratório Forçado/fisiologia , Pacientes Internados , Idoso , Doença da Artéria Coronariana/fisiopatologia , Estudos Transversais , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Índice de Gravidade de Doença
19.
Entropy (Basel) ; 20(12)2018 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33266669

RESUMO

Conventional quantization-based watermarking may be easily estimated by averaging on a set of watermarked signals via uniform quantization approach. Moreover, the conventional quantization-based method neglects the visual perceptual characteristics of the host signal; thus, the perceptible distortions would be introduced in some parts of host signal. In this paper, inspired by the Watson's entropy masking model and logarithmic quantization index modulation (LQIM), a logarithmic quantization-based image watermarking method is developed by using the wavelet transform. Furthermore, the novel method improves the robustness of watermarking based on a logarithmic quantization strategy, which embeds the watermark data into the image blocks with high entropy value. The main significance of this work is that the trade-off between invisibility and robustness is simply addressed by using the logarithmic quantizaiton approach, which applies the entropy masking model and distortion-compensated scheme to develop a watermark embedding method. In this manner, the optimal quantization parameter obtained by minimizing the quantization distortion function effectively controls the watermark strength. In terms of watermark decoding, we model the wavelet coefficients of image by the generalized Gaussian distribution (GGD) and calculate the bit error probability of proposed method. Performance of the proposed method is analyzed and verified by simulation on real images. Experimental results demonstrate that the proposed method has the advantages of imperceptibility and strong robustness against attacks covering JPEG compression, additive white Gaussian noise (AWGN), Gaussian filtering, Salt&Peppers noise, scaling and rotation attack, etc.

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