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1.
J Phys Condens Matter ; 35(6)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36347036

RESUMO

We study the Landau levels and magneto-optical properties of bulk black phosphorus (BP) subjected to an in-plane magnetic field along the armchair direction based on an effectivek⋅pHamiltonian. We analytically obtain the Landau levels by the perturbation method, which agrees well with the results of numerical diagonalization. By using the Kubo formula, we find the magneto-optical transition selection rules and conductance spectra for inter-band transitions are highly anisotropic. In particular, for linearly polarized light along the armchair direction, the magneto-optical transition selection rule isΔn= 0, wherenis the Landau level index. However, for linearly polarized light along the zigzag and stacking direction, the magneto-optical transition selection rules becomeΔn= ±1. The magneto-optical conductance excited by linearly polarized light along the armchair direction is two order of magnitude larger than those excited by linearly polarized light along the zigzag and stacking direction because the inter-band coupling only exists in the armchair direction. Our results are useful to detect the band parameters of BP and design magnetically controlled optical devices based on it.

2.
Medicine (Baltimore) ; 98(32): e16790, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393407

RESUMO

To study the long-term curative effect of repeat percutaneous balloon mitral valvuloplasty (PBMV) in patients with mitral restenosis.In our study, mitral restenosis developed in 39 patients after PBMV. Repeat PBMV was performed according to the improved Inoue method. All patients were followed up.Of 39 patients, 36 were successfully treated with repeat PBMV (achievement ratio, 92.3%). Immediately after repeat PBMV, clinical symptoms and left atrial mean pressure (LAP), pulmonary artery systolic pressure (PASP), mitral valve gradient (MVG), and mitral valve orifice area (MVA) improved significantly (24.50 ±â€Š6.54 mmHg vs 9.66 ±â€Š4.21 mmHg for LAP, 1.05 ±â€Š0.19 cm vs 2.23 ±â€Š0.22 cm for MVA, 17.03 ±â€Š4.52 mmHg vs 7.79 ±â€Š4.07 mmHg for MVG, 58.12 ±â€Š12.68 mmHg vs 31.45 ±â€Š10.02 mmHg for PASP; P <.05). Meanwhile, left atrial end-diastolic dimension (LAD) was altered slightly (4.71 ±â€Š0.75 vs 4.07 ±â€Š0.69, P >.05). The 36 patients were followed up for 69 ±â€Š23 (12-146) months. After long-term follow-up immediately after repeat PBMV, the results did not show a significant change (2.23 ±â€Š-0.22 cm vs 2.02 ±â€Š-0.21 cm for MVA, 7.79 ±â€Š-4.07 mmHg vs 9.15 ±â€Š-4.11 mmHg for MVG; P >.05) and were approximated to those shortly after repeat PBMV (2.23 ±â€Š0.22 cm vs 2.02 ±â€Š0.21 cm for MVA, 7.79 ±â€Š4.07 mmHg vs 9.15 ±â€Š4.11 mmHg for MVG; P > 0.05). LAD did not change significantly (4.13 ±â€Š0.71 cm vs. 4.07 ±â€Š0.69 cm; P >.05). The long-term follow-up results showed that cardiac function and quality of life were significantly improved in most patients.It would be safe for patients with mitral restenosis to undergo repeat PBMV. Appropriate cases should be selected, and treatment should be performed cautiously. Short- and long-term curative effects would be satisfactory. We suggested that repeat PBMV be the first choice for patients with mitral restenosis after first PBMV.


Assuntos
Valvuloplastia com Balão/métodos , Estenose da Valva Mitral/cirurgia , Reoperação/métodos , Valvuloplastia com Balão/efeitos adversos , Humanos , Valva Mitral/diagnóstico por imagem , Qualidade de Vida , Reoperação/efeitos adversos
3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(1): 100-104, 2019 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-30837410

RESUMO

Adipocytokines are polypeptides or proteins that are secreted by fat cells with a wide range of biological activities. Adiponectin is a fatty cytokine with insulin sensitization. It possesses the function of anti- diabetes, atherosclerosis and anti-inflammation. Adiponectin may participate in regulating the development of cognitive impairment, which is considered as a new regulatory factor for cognitive impairment.


Assuntos
Disfunção Cognitiva , Resistência à Insulina , Adiponectina , Diabetes Mellitus , Humanos , Insulina
4.
Sensors (Basel) ; 19(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634612

RESUMO

As important sources in fault diagnosis of rotary machinery, vibration signals are usually processed in the time or frequency domain as features to distinguish different classes of faults. However, these kinds of processing methods always ignore the corresponding relations among multiple signals, resulting in information loss. In this paper, a new fault description strategy named vibration image is proposed, based on which three new kinds of features are extracted, containing coupling information between different channels of vibration signals. Additionally, a new feature fusion method called two-layer AdaBoost is designed to train the fault recognition model, which avoids overfitting when the dataset is not large enough. Features based on vibration images combined with two-layer AdaBoost are adopted to diagnose faults of rotary machinery. Taking an active magnetic bearing-rotor system as the experimental platform, a dataset with four classes of faults is collected and our algorithm achieves good performance. Meanwhile, features based on vibration images and two-layer AdaBoost are both proved to be efficient separately.

5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(12): 1330-1337, 2019 Dec 28.
Artigo em Chinês | MEDLINE | ID: mdl-31969496

RESUMO

OBJECTIVE: To study the protective effect of Xingnaojing Injection on early global brain ischemia-induced deep coma in rats.
 Methods: The deep coma model was induced by global brain ischemia by using four-vessel occlusion method in male SD rats. According to the body weight, the rats were randomly divided into 8 groups: a model control group, three different dose of Xingnaojing Injection (1.8, 3.6 and 5.4 mL.kg-1) groups, a Xingnaojing Injection (3.6 mL.kg-1) plus PI3K inhibitor group, a naloxone injection (0.04 mL.kg-1) group and a naloxone injection (0.04 mL.kg-1) plus Xingnaojing Injection (3.6 mL.kg-1) group (n=8 per group). In addition, eight animals served as the sham group were performed same operation with the model group excepting no blockage of the blood vessels. After the operation, three different doses of Xingnaojing Injection and/or naloxone injection were given intravenously once a day for three days. Ten µL PI3K inhibitor (LY294002, 10 mmol/L) was injected via anterior cerebral ventricle at once after global brain ischemia. The awakening time after the first drug treatment, the grasping power and the autonomous activity within 10 min after the last drug treatment were recorded. The levels of both dopamine (DA) and glutamate (Glu) in cerebrospinal fluid were detected by ELISA. The pathological changes were observed in brain tissue slices with HE staining and the protein levels of Akt/p-Akt and cAMP-response element binding protein (CREB)/p-CREB in hippocampus were detected by Western blotting.
 Results: Comparing with the model group, single administration of Xingnaojing Injection could significantly shorten the waking time (P<0.05) and continuous administration of Xingnaojing Injection for 3 d could increase grasping power, distance, frequency and duration of autonomous activities (P<0.05 or P<0.01) in the deep coma rat. Also, Xingnaojing Injection could inhibit these increases in neurotransmitters DA and Glu contents (P<0.05 or P<0.01), and improve pathological changes of hippocampal tissue. Xingnaojing Injection significantly induced protein phosphorylation of both Akt and CREB (P<0.05 or P<0.01); this effect was inhibited by PI3K inhibitor (P<0.05 or P<0.01). Moreover, the protective effects of naloxone on awakening time, grasping power, the autonomous activity and hippocampus damage in global brain ischemia-induced deep coma could be enhanced by joint use of Xingnaojing Injection (P<0.05 or P<0.01).
 Conclusion: Xingnaojing Injection could significantly improve deep coma induced by global brain ischemia in rat, which is related to inducing PI3K/Akt-dependent protein phosphorylation of CREB, and reducing hippocampal damage. The protective effect of Xingnaojing Injection is synergistically enhanced by naloxone.


Assuntos
Isquemia Encefálica , Animais , Encéfalo , Coma , Medicamentos de Ervas Chinesas , Masculino , Fosfatidilinositol 3-Quinases , Ratos , Ratos Sprague-Dawley
6.
J Phys Condens Matter ; 29(8): 085301, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28000622

RESUMO

Based on the tight-binding model and dual-probe scanning tunneling microscopy technology, we theoretically investigate the electronic structure and local property in the passivated AA-stacked bilayer armchair-edge graphene nanoribbons (AABLAGNRs). We show that they are highly sensitive to the size of the ribbons, which is evidently different from the single-layer armchair-edge graphene nanoribbons. The '3p' rule only applies to the narrow AABLGNRs. Namely, in the passivated 3p- and (3p + 1)-AABLGNRs, the narrow ribbons are semiconducting while the medium and wide ribbons are metallic. Although the passivated (3p + 2)-AABLGNRs are metallic, the '3j' rule only applies to the narrow and medium ribbons. Namely, electrons are in the semiconducting states at sites of line 3j while they are in the metallic states at other sites. This induces a series of parallel and discrete metallic channels, consisting of lines 3j - 1 and 3j - 2, for the low-energy electronic transports. In the passivated wide (3p + 2)-AABLGNRs, all electrons are in the metallic states. Additionally, the '3p' and '3j' rules are controllable to disappear and reappear by applying an external perpendicular electric field. Resultantly, an electric filed-driven current switch can be realized in the passivated narrow and medium (3p + 2)-AABLGNRs.

7.
Appl Opt ; 55(31): 8855-8859, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27828285

RESUMO

We propose a new method for secret image sharing with the (3,N) threshold scheme based on phase-shifting interferometry. The secret image, which is multiplied with an encryption key in advance, is first encrypted by using Fourier transformation. Then, the encoded image is shared into N shadow images based on the recording principle of phase-shifting interferometry. Based on the reconstruction principle of phase-shifting interferometry, any three or more shadow images can retrieve the secret image, while any two or fewer shadow images cannot obtain any information of the secret image. Thus, a (3,N) threshold secret sharing scheme can be implemented. Compared with our previously reported method, the algorithm of this paper is suited for not only a binary image but also a gray-scale image. Moreover, the proposed algorithm can obtain a larger threshold value t. Simulation results are presented to demonstrate the feasibility of the proposed method.

8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 39(12): 1124-8, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22336506

RESUMO

OBJECTIVE: To investigate the short and long-term outcome post percutaneous balloon mitral valvuloplasty (PBMV) in mitral valve stenosis patients with different mitral valve morphology. METHODS: Mitral valve morphology was graded according to the Wilkins scoring system, 385 eligible patients were divided into echocardiographic scores > 8 group (n = 125) and ≤ 8 group (n = 260). Patients were followed up after PBMV according to the improved Inoue method. RESULTS: PBMV was successful in 370 patients, the success rate of PBMV in > 8 group was significantly lower than in ≤ 8 group (92.8% vs. 97.7%, P < 0.05). Hemodynamic parameters improved significantly in both groups (all P < 0.05) at 6 months post PBMV. Compared to pre-PBMV, improvement on left atrial mean pressure [(14.22 ± 5.02) mm Hg vs. (15.44 ± 5.19) mm Hg (1 mm Hg = 0.133 kPa)], pulmonary artery systolic pressure [(26.13 ± 9.27) mm Hg vs. (31.93 ± 9.98) mm Hg], mitral valve gradient [(9.21 ± 4.11) mm Hg vs. (10.16 ± 4.21) mm Hg] and area of mitral valve orifice [(1.02 ± 0.15) cm(2) vs. (1.20 ± 0.22) cm(2)] post PBMV was less in > 8 group (116 cases) than those in ≤ 8 group (254 cases, all P < 0.05). Three hundreds and fifty three patients were followed up for (78 ± 20) months. Echocardiographic parameters post PBMV improved significantly in both groups compared with the pre-PBMV values during follow-up (all P < 0.05). However, left atrial mean pressure, pulmonary artery systolic pressure, mitral valve gradient and area of mitral valve orifice in > 8 group (108 cases) improved less than those in ≤ 8 group (245 cases) [(13.28 ± 5.06) mm Hg vs. (14.77 ± 5.17) mm Hg, (21.19 ± 9.17) mm Hg vs. (28.92 ± 9.91) mm Hg, (7.30 ± 4.40) mm Hg vs. (9.16 ± 4.28) mm Hg, (0.92 ± 0.17) cm(2) vs. (1.07 ± 0.20) cm(2); all P < 0.05]. The incidence of mitral restenosis was also significantly higher in > 8 group than in ≤ 8 group (20.4% vs. 8.2%, P < 0.05). CONCLUSIONS: The mitral valve morphology played a key role on the outcome post PBMV in patients with mitral valve stenosis. Patients with lower echocardiographic scores benefit more from PBMV than patients with higher echocardiographic scores.


Assuntos
Valvuloplastia com Balão/métodos , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/terapia , Valva Mitral/anatomia & histologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia , Adulto Jovem
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