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1.
Ann Med ; 55(1): 2234934, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37452706

RESUMO

BACKGROUND: This study aimed to identify the appropriate signature veins for the right adrenal gland using a 3D model fused with adrenal venography images and to verify their accuracy through the selectivity index (SI) >2. METHODS: We analyzed the right adrenal venography images of 41 patients who underwent adrenal venous sampling (AVS). These images were merged with a 3D structure of the adrenal gland to identify the signature veins of the right adrenal gland. We then used the signature veins observed during adrenal venography to determine the optimal position of the catheter tip during AVS for 53 other patients. Finally, we verified the accuracy of this method according to the SI. RESULTS: We successfully fused the 3D models of 41 cases with adrenal venography images. We identified the trunk branch type as the major venous morphology in the right anterior oblique at degrees of 30 (38 cases, 92.7%). In addition, the central vein, brush vein, uvula vein, and capsular vein were identified as signature veins for the right AVS. The accuracy of AVS was 100% in the other 53 patients, as verified by an SI >2. CONCLUSIONS: Our study identified the right adrenal signature veins, including the previously overlooked uvula vein, which can be used to determine the position of the catheter tip and improve the success rate of AVS.


The majority of the venography types observed in patients in the right anterior oblique at 30 degrees during adrenal venography were trunk branch types, while irregular or hollow triangle types were infrequent.The signature veins identified during right adrenal venous sampling were the central vein, brush vein, uvula vein, and capsular vein.The right adrenal signature veins, particularly the uvula vein, which has not been given much attention in the past, can serve as a reference to verify the position of the catheter tip and enhance the success rate of adrenal venous sampling.


Assuntos
Hiperaldosteronismo , Humanos , Hiperaldosteronismo/diagnóstico , Cateterismo/métodos , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/irrigação sanguínea , Flebografia/métodos , Estudos Retrospectivos , Aldosterona
2.
Front Endocrinol (Lausanne) ; 13: 1005934, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36506080

RESUMO

Introduction: Unilateral primary aldosteronism (UPA) and bilateral primary aldosteronism (BPA) are the two subtypes of PA. Discriminating UPA from BPA is of great significance. Although adrenal venous sampling (AVS) is the gold standard for diagnosis, it has shortcomings. Thus, improved methods are needed. Methods: The original data were extracted from the public database "Dryad". Ten parameters were included to develop prediction models for PA subtype diagnosis using machine learning technology. Moreover, the optimal model was chose and validated in an external dataset. Results: In the modeling dataset, 165 patients (71 UPA, 94 BPA) were included, while in the external dataset, 43 consecutive patients (20 UPA, 23 BPA) were included. The ten parameters utilized in the prediction model include age, sex, systolic and diastolic blood pressure, aldosterone to renin ratio (ARR), serum potassium, ARR after 50 mg captopril challenge test (CCT), primary aldosterone concentration (PAC) after saline infusion test (SIT), PAC reduction rate after SIT, and number of types of antihypertensive agents at diagnosis. The accuracy, sensitivity, specificity, F1 score, and AUC for the optimal model using the random forest classifier were 90.0%, 81.8%, 96.4%, 0.878, and 0.938, respectively, in the testing dataset and 81.4%, 90.0%, 73.9%, 0.818 and 0.887, respectively, in the validating external dataset. The most important variables contributing to the prediction model were PAC after SIT, ARR, and ARR after CCT. Discussion: We developed a machine learning-based predictive model for PA subtype diagnosis based on ten clinical parameters without CT imaging. In the future, artificial intelligence-based prediction models might become a robust prediction tool for PA subtype diagnosis, thereby, might reducing at least some of the requests for CT or AVS and assisting clinical decision-making.


Assuntos
Hiperaldosteronismo , Humanos , Hiperaldosteronismo/diagnóstico , Inteligência Artificial , Aldosterona , Captopril , Aprendizado de Máquina
3.
Micromachines (Basel) ; 13(8)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36014244

RESUMO

Aiming at exploring the material removal mechanism for sapphire using diamond abrasive grains at the microscopic level, this paper modeled and analyzed the microscopic yield behavior of diamond abrasive grains in the FAP grinding process of sapphire. Molecular dynamics were used to simulate the effects of abrasive particle size on the cutting force, potential energy, and temperature in the Newtonian zone during micro-cutting. The effect of different abrasive particle sizes on material removal was analyzed through experiments. The simulation results show that the abrasive particle radius was 12 Å, the micro-cutting force reached more than 3500 nN, while the cutting force with an abrasive particle radius of 8 Å only reached 1000 nN. Moreover, the potential energy, cutting force, and temperature in the Newtonian zone between the sapphire crystal atoms also increased. The results showed that the material removal rate saw a nonlinear increasing trend with the increase in particle sizes, while the surface roughness showed an approximately linear increase. Both of them showed a similar trend. The experimental results lay a theoretical basis for the selection of the lapping process parameters in sapphire.

4.
Clin Appl Thromb Hemost ; 27: 1076029621999722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33651650

RESUMO

We investigated the association between serum adenosine deaminase and coronary artery calcification (CAC) in type 2 diabetes mellitus (T2DM) patients. The cross-sectional study included 459 patients with T2DM, the clinical and laboratory tests were performed, and all T2DM patients were separated into the 3 groups based on the tertile of serum adenosine deaminase levels. In the baseline data, the CAC score had statistically significant differences between the 3 groups (p < 0.001). Serum adenosine deaminase levels were positively correlated with CAC score in T2DM patients (r = 0.355, p < 0.001). The results of multiple linear regression analysis showed that serum adenosine deaminase was independent positively correlated with CAC score in T2DM patients (r = 0.255, p < 0.001). Receiver-operating characteristic curve analysis showed that area under curve was 0.750 to identify T2DM patients with CAC. Serum adenosine deaminase levels are correlated with CAC scores in T2DM patients, clinically, serum adenosine deaminase should be considered as an underlying marker to determine the severity of atherosclerosis in T2DM patients.


Assuntos
Adenosina Desaminase/sangue , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Calcificação Vascular/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Sci Total Environ ; 609: 1075-1084, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28787781

RESUMO

The aim of this study is to investigate the flow field characteristics in ABL (Atmospheric Boundary Layer) flow over multiple hills and valleys in two-dimensional models under neutral conditions. Active turbulence grids and boundary layer generation frame were used to simulate the natural winds in wind tunnel experiments. As a result, the mean wind velocity, the velocity vector diagram and turbulence intensity around the hills were investigated by using a PIV (Particle Image Velocimetry) system. From the measurement results, it was known that the average velocity was increased along the upstream slope of upside hill, and then separated at the top of the hills, the acceleration region of U/Uref>1 was generated at the downstream of the hill. Meanwhile, a large clockwise circulation flow was generated between the two hill models. Moreover, the turbulence intensity showed small value in the circulation flow regions. Compared to 1H model, the turbulence intensity in the mainstream direction showed larger value than that in the vertical direction. This paper provided a better understanding of the wind energy distribution on the terrain for proper selection of suitable sites for installing wind farms in the ABL.

6.
J Phys Condens Matter ; 27(49): 495602, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26575485

RESUMO

We show evidence that the competition between the antiferromagetic metallic phase and the charge- and orbital-ordered insulating phase at the reentrant phase boundary of a layered manganite, La0.99Sr2.01Mn2O7, can be manipulated using ultrafast optical excitation. The time-dependent evolution of the Jahn-Teller superlattice reflection, which indicates the formation of the charge and orbital order, was measured at different laser fluences. The laser-induced enhancement and reduction the Jahn-Teller reflection intensity shows a reversal of sign between earlier (~10 ns) and later (~150 ns) time delays during the relaxation after photo excitation. This effect is consistent with a scenario whereby the laser excitation modulates the local competition between the metallic and the insulating phases.

7.
Microsc Microanal ; 20(6): 1791-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25263577

RESUMO

To date, it is unclear whether chemical order (or disorder) is in any way connected to double exchange, electronic phase separation, or charge ordering (CO) in manganites. In this work, we carry out an atomic resolution study of the colossal magnetoresistant manganite La(2-2x)Sr(1+2x)Mn2O7 (LSMO). We combine aberration-corrected electron microscopy and spectroscopy with spectroscopic image simulations, to analyze cation ordering at the atomic scale in real space in a number of LSMO single crystals. We compare three different compositions within the phase diagram: a ferromagnetic metallic material (x=0.36), an insulating, antiferromagnetic charge ordered (AF-CO) compound (x=0.5), which also exhibits orbital ordering, and an additional AF sample (x=0.56). Detailed image simulations are essential to accurately quantify the degree of chemical ordering of these samples. We find a significant degree of long-range chemical ordering in all cases, which increases in the AF-CO range. However, the degree of ordering is never complete nor can it explain the strongly correlated underlying ordering phenomena. Our results show that chemical ordering over distinct crystallographic sites is not needed for electronic ordering phenomena to appear in manganites, and cannot by itself explain the complex electronic behavior of LSMO.

8.
Phys Rev Lett ; 110(19): 196404, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23705726

RESUMO

It was recently discovered that the low-temperature, charge-ordered phase of 1T-TiSe(2) has a chiral character. This unexpected chirality in a system described by a scalar order parameter could be explained in a model where the emergence of relative phase shifts between three charge density wave components breaks the inversion symmetry of the lattice. Here, we present experimental evidence for the sequence of phase transitions predicted by that theory, going from disorder to nonchiral and finally to chiral charge order. Employing x-ray diffraction, specific heat, and electrical transport measurements, we find that a novel phase transition occurs ~7 K below the main charge ordering transition in TiSe(2), in agreement with the predicted hierarchy of charge-ordered phases.

9.
Inorg Chem ; 50(4): 1184-93, 2011 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-21247072

RESUMO

Yb(3)AuGe(2)In(3) was obtained as large single crystals in high yield from reactions run in liquid indium. Single crystal X-ray diffraction data show that Yb(3)AuGe(2)In(3) is an ordered variant of YbAuIn with lattice constants, a = b = 7.3153(8) Å and c = 4.4210(5) Å, and space group P(6)2m. The parent compound YbAuIn was also studied for comparison. YbAuIn crystallizes in the ZrNiAl structure type, hexagonal, P(6)2m space group with lattice parameters a = b = 7.7127(11) Å and c = 4.0294(8) Å. In Yb(3)AuGe(2)In(3), Ge substitutes for one of the two Au positions in the ternary compound Yb(3)Au(3)In(3). The structure can be described as alternating [Ge(2)In(3)] and [Yb(3)Au] slabs that stack along the c-axis. The magnetic susceptibility data follow a modified Curie-Weiss law. The effective magnetic moment µ(eff) of 0.52 µ(B)/Yb atom was deduced from the Curie constant and Curie-Weiss constant of θ(p) = -1.5 K indicating antiferromagnetic interactions in Yb(3)AuGe(2)In(3). X-ray absorption near edge spectroscopy (XANES) measurements indicate intermediate valency for Yb in both compounds. The metallic nature of both compounds was confirmed by the resistivity measurements. Specific heat data for Yb(3)AuGe(2)In(3) and YbAuIn give an electronic γ term of 31 and 84 mJ/mol·K(2), respectively, suggesting that the ternary analog is a "light" heavy fermion compound.

10.
Phys Rev Lett ; 98(16): 167201, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17501455

RESUMO

Contrary to conventional wisdom, our purified La 2-2x Sr 1+2x Mn2O7 crystals exhibit CE-type orbital and charge order as the low-temperature ground state for a hole doping level h=0.5. For small deviations from h=0.5, the high-temperature CE phase is replaced at low temperatures by an A-type antiferromagnet without coexistence. Larger deviations result in a lack of CE order at any temperature. Thus, small inhomogeneities in cation or oxygen composition could explain why others commonly see this reentrance with coexistence.

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