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1.
Clin Invest Med ; 45(4): E33-38, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36586102

RESUMO

PURPOSE: To determine correlation between genetic susceptibility of type 2 diabetes mellitus (T2DM) and Src homology 2 B adapter protein 1 (SH2B1) gene polymorphism in a diabetic population.  Methods: A total of 111 T2DM patients (DM group) and 34 healthy controls (NC group) from Shanxi Provincial People's Hospital were included in this study. Exon 9 of the SH2B1 gene was detected using the Sanger sequencing method, and the relationship between SH2B1 gene polymorphism and diabetes was analyzed.  Results: Comparison of the data between the two groups showed that the values of TG, the updated HOMA of insulin resistance (HOMA2-IR), weight, body mass index, waist circumference, fasting blood glucose and fasting insulin levels of the DM group were higher than those of the NC group (P < 0.05). The HOMA2 insulin sensitivity (%S) of the DM group was lower than that of the NC group (P < 0.05). Sequencing analysis revealed that the following five single nucleotide polymorphisms in exon 9 of SH2B1 may be related to T2DM: rs181578610, rs550079240, chr16.28884655, chr16.28884659 and chr16.28884831. Among them, chr16.28884655 was found to be significantly related to diabetes; this site, located on the NM_015503 exon, was related to TG, LDL-C and waist circumference. CONCLUSION: The SH2B1 gene locus chr16.28884655 was found to be significantly related to genetic susceptibility to T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Predisposição Genética para Doença , Resistência à Insulina/genética , Polimorfismo de Nucleotídeo Único/genética , Índice de Massa Corporal , Glicemia/análise , Glicemia/metabolismo , Insulina , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
2.
Sensors (Basel) ; 22(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36298177

RESUMO

The stable operation of climbing robots exposed to high winds is of great significance for the health-monitoring of structures. This study proposes an anole lizard-like climbing robot inspired by its superior wind resistance. First, the stability mechanism of the anole lizard body in adhesion and desorption is investigated by developing adhesion and desorption models, respectively. Then, the hypothesis that the anole lizard improves its adhesion and stability performance through abdominal adjustment and trunk swing is tested by developing a simplified body model and kinematic model. After that, the structures of the toe, limb, and multi-stage flexible torso of the anole lizard-like climbing robot are designed. Subsequently, the aerodynamic behavior of the proposed robot under high-speed airflow are investigated using finite element analysis. The results show that when there is no obstacle, the climbing robot generates the normal force to enhance toepad friction and adhesion by tuning the abdomen's shape to create an air pressure difference between the back and abdomen. When there is an obstacle, a component force is obtained through periodic oscillation of the spine and tail to resist the frontal winds resulting from the vortex paths generated by the airflow behind the obstacle. These results confirm that the proposed hypothesis is correct. Finally, the adhesion and wind resistance performance of the anole lizard-like climbing robot is tested through the developed experimental platform. It is found that the adhesion force is equal to 50 N when the pre-pressure is 20 N. Further, it is shown that the normal pressure of the proposed robot can reach 76.6% of its weight in a high wind of 14 m/s.


Assuntos
Lagartos , Animais , Vento , Fenômenos Biomecânicos , Extremidades
3.
Int J Mol Sci ; 23(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36012160

RESUMO

With the rapid development of wearable smart electronic products, high-performance wearable flexible strain sensors are urgently needed. In this paper, a flexible strain sensor device with Fe NWs/Graphene/PEDOT:PSS material added under a porous structure was designed and prepared. The effects of adding different sensing materials and a different number of dips with PEDOT:PSS on the device performance were investigated. The experiments show that the flexible strain sensor obtained by using Fe NWs, graphene, and PEDOT:PSS composite is dipped in polyurethane foam once and vacuum dried in turn with a local linearity of 98.8%, and the device was stable up to 3500 times at 80% strain. The high linearity and good stability are based on the three-dimensional network structure of polyurethane foam, combined with the excellent electrical conductivity of Fe NWs, the bridging and passivation effects of graphene, and the stabilization effect of PEDOT:PSS, which force the graphene-coated Fe NWs to adhere to the porous skeleton under the action of PEDOT:PSS to form a stable three-dimensional conductive network. Flexible strain sensor devices can be applied to smart robots and other fields and show broad application prospects in intelligent wearable devices.


Assuntos
Grafite , Compostos Bicíclicos Heterocíclicos com Pontes/química , Grafite/química , Polímeros/química , Porosidade
4.
Molecules ; 27(15)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35897893

RESUMO

Flexible strain sensors, when considering high sensitivity and a large strain range, have become a key requirement for current robotic applications. However, it is still a thorny issue to take both factors into consideration at the same time. Here, we report a sandwich-structured strain sensor based on Fe nanowires (Fe NWs) that has a high GF (37-53) while taking into account a large strain range (15-57.5%), low hysteresis (2.45%), stability, and low cost with an areal density of Fe NWs of 4.4 mg/cm2. Additionally, the relationship between the contact point of the conductive network, the output resistance, and the areal density of the sensing unit is analyzed. Microscopically, the contact points of the conductive network directly affect the sensor output resistance distribution, thereby affecting the gauge factor (GF) of the sensor. Macroscopically, the areal density and the output resistivity of the strain sensor have the opposite percolation theory, which affects its linearity performance. At the same time, there is a positive correlation between the areal density and the contact point: when the stretching amount is constant, it theoretically shows that the areal density affects the GF. When the areal density reaches this percolation threshold range, the sensing performance is the best. This will lay the foundation for rapid applications in wearable robots.

5.
Nanotechnology ; 31(39): 395708, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32544893

RESUMO

Reducing the filling content of high-density ferromagnetic particles is a key prerequisite for obtaining lightweight absorbers. To this end, large iron nanowires (Fe NWs) with high length-diameters, uniform length of approximately 21 µm and diameters of approximately 60 nm were synthesized through a facile magnetic field-induced in situ reduction method without templates and surfactants. The phase structures, and micromorphology of the high-aspect-ratio Fe NWs were analyzed, and the electromagnetic properties of Fe NWs-paraffin composites were measured with a vector network analyzer at 2-18 GHz. The Fe NWs-paraffin composite with a low filler loading also exhibited satisfactory microwave absorption performance, and the composites filled with 20 wt.% of as-prepared Fe NWs shows a minimum reflection loss (RLmin) of -44.67 dB at 2.72 GHz and effective absorption bandwidth (EAB) with reflection loss below -10 dB reached 8.56 GHz at a layer thickness of 1.42 mm. At a thickness of 3 mm, the RLmin value and EAB (RL ⩽ -10 dB) reached -29.74 dB and 3.28 GHz (3.84-7.12 GHz), respectively. This study suggests that Fe NWs with high-aspect-ratios have promising microwave absorbing applications, and provides a good reference for the preparation of ferromagnetic metal-based lightweight electromagnetic wave-absorbing materials.

6.
Nanotechnology ; 31(14): 145601, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31842005

RESUMO

High-performance iron nanowires have attracted wide attention from researchers due to their 'controllable' arrangement distribution by magnetic fields. In this paper, a simple magnetic field assisted in situ reduction method was proposed to synthesize Fe NWs with high aspect ratio, small-diameter, and good dispersion. A detailed parametric study determining the relationship among the final morphologies of the products and magnetic field, injection sequence of sodium borohydride that was injected into ferrous sulfate heptahydrate, reactant concentration, and injection rate is presented. The as-synthesized Fe NWs were analyzed by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and vibrating sample magnetometry. A plausible mechanism for the formation of high-aspect-ratio Fe NWs is proposed. The SEM images showed the dependence of the NWs morphology and aspect ratio on synthesis parameters. Magnetic field and injection sequence showed considerable influences on the synthesis of high-aspect-ratio Fe NWs. In the absence of magnetic field or with the changes in injection sequence, only the Fe flakes were obtained. The NWs diameter decreased, and the aspect ratio increased with the increase in injection rate. The FeSO4·7H2O and NaBH4 concentration considerably influenced the aspect ratio of the product, which increased first, decreased, and then increased again with the increase in FeSO4·7H2O concentration. Meanwhile, the product aspect ratio increased and then became saturated with the increase in NaBH4 concentration Thus, an optimum synthesis process was obtained, with the average aspect ratio of 350, and the average diameter of 60 nm. The results reported in this paper provide a basis for optimizing the growth of Fe NWs by magnetic field-assisted method.

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