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1.
J Opt Soc Am A Opt Image Sci Vis ; 40(10): 1918-1925, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855547

RESUMO

The analytical formulas for spectral density, degree of coherence, and effective beam widths of complex coherent square Gaussian-Schell-model (GSM) beams in a uniaxial crystal orthogonal to the optical axis are derived. Based on these analytical formulas, the evolution properties are investigated by a set of numerical examples. It is demonstrated that the complex coherent square GSM beams spread at different rates in the directions parallel and orthogonal to the optical axis due to the anisotropic crystal, but the self-shift effect of the light field is almost unaffected by the fact that the uniaxial crystal is anisotropic. The effect of anisotropy of the uniaxial crystal on the effective width of the beam in the x direction and that in the y direction is completely opposite. The results provide a way for the modulation of the complex coherent square GSM beams and enrich the propagation theory of uniaxial crystal.

2.
Opt Express ; 31(13): 20941-20954, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381206

RESUMO

Metasurface has extraordinary capability in the wavefront manipulation of electromagnetic waves, which provides an effective method for meta-holographic technology. However, holographic technology mostly focuses on the generation of the single-plane image, which lacks a systematic design method to generate, store, and reconstruct multi-plane holographic images. In this paper, the Pancharatnam-Berry phase meta-atom is designed as electromagnetic controller with the characteristics of the full phase range and high reflection amplitude. Different from the single-plane holography method, a novel multi-plane retrieval algorithm is proposed for the computation of the phase distribution. The metasurface, containing only 24 × 24 (30 × 30) elements, can produce high-quality single-(double-) plane image(s) with fewer elements. Meanwhile, the implementation of the compressed sensing approach stores almost all the holographic image information under a 25% compression ratio and reconstructs the image by the compressed data. The experimental measurements of the samples are consistent with the theoretical and simulated results. This systematic scheme provides an innovative and effective way for designing miniaturized meta-devices to generate high-quality images, which relate to practical applications including high-density data storage, information security, and imaging.

3.
Front Pharmacol ; 14: 1136778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998612

RESUMO

Objective: Yiqi Huazhuo Decoction (YD) reduces blood glucose, glycated hemoglobin, body weight, and insulin resistance in patients with type 2 diabetes mellitus (T2DM), but its exact mechanisms are unknown. This study investigated the therapeutic effects and mechanisms of YD on impaired insulin secretion in T2DM rats. Methods: T2DM rats were randomized to the model, YD-lo (15 mg/kg/d YD, 10 weeks), YD-hi (30 mg/kg/d YD, 10 weeks), positive drug (TAK-875), and healthy control groups. The rats underwent an oral glucose tolerance test (OGTT), glucose-stimulated insulin secretion (GSIS) test, and serum lipid measurements. High-fat and high-glucose-injured RIN-m5f cells were treated with YD (30 or 150 mg/mL) for 48 h. GPR40 and IP3R-1 expression levels were determined by immunofluorescence, qRT-PCR, and western blot. Results: Compared with the model group, the OGTT area under the curve (AUC) in the YD-hi group was decreased by 26.7%, the insulin release test (IRT) AUC in the YD-hi group was increased by 45.9%, and the GSIS AUC was increased by 33.9% (p < 0.05). Compared with the model cells, the insulin secretion after glucose stimulation in the YD-hi group was increased by 24.5%, similar to the TAK-875 group (23.1%) (p > 0.05). GPR40 and IP3R-1 mRNA in the model cells were decreased by 49.5% and 51.2% compared with the control cells (p < 0.05). In the YD-hi group, GPR40 and IP3R-1 mRNA levels were increased by 58.1% and 39.3% (p < 0.05), similar to the TAK-875 group. The changes in protein expression were similar to mRNA. Conclusion: YD promotes insulin secretion from pancreatic islet ß-cell in T2DM rats by regulating the GPR40-IP3R-1 pathway, thereby reducing blood glucose.

4.
J Colloid Interface Sci ; 610: 546-556, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34839915

RESUMO

Billowy interest during nitrogen reduction reaction (NRR) for single-atom catalysts (SACs) has been evoked by the discovery of single transition metal (TM) atom structures featured by TM-Nx coordinate sites as an excellent catalytic center. However, a great challenge of currently available SACs, far away from industrial requirement, is the low activity and poor selectivity. Therefore, in NRR, the first-principles high-throughput screening calculations were performed to evaluate the feasibility of a single TM atom (from Sc to Au) embedded an artificial holey defective SnN3 (d-SnN3) monolayer. Here, all TM atoms can be stably anchored on d-SnN3 (TM/d-SnN3), meanwhile, most of adsorbed N2 molecules can be favorably activated via the "σ donation - π* back-donation" interaction. Eventually, among 27 TM centers, V, Mo, Hf and Ta/d-SnN3 stand out because of extremely low limiting potential (-0.21, -0.40, -0.56 and -0.54 V, respectively), lower than majority of TM-based NRR catalysts and far below that of the Ru (0001) surface (0.98 V), indicative of fast kinetics and low energy cost of NRR. Moreover, their intrinsic characteristic, such as centralized spin-polarization on these TM atoms, high-efficient prohibition of the competitive hydrogen evolution reaction is responsible for high selectivity with theoretical faradic efficiency of 100%. Also, multiple-level descriptors including ΔG∗N, ICOHP, and Φ were used to make the source of NRR activity clear, realizing an efficient and quick prescreening among different candidates. Particularly, their excellent durability, kinetic stability and synthetic accessibility guarantee the feasibility in real experimental conditions.


Assuntos
Hidrogênio , Nitrogênio , Catálise , Cinética
5.
Insects ; 12(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34680661

RESUMO

Apis cerana abansis, widely distributed in the southeastern margin of the Qinghai-Tibet Plateau, is considered an excellent model to study the phenotype and genetic variation for highland adaptation of Asian honeybee. Herein, we assembled and annotated the chromosome-scale assembly genome of A. cerana abansis with the help of PacBio, Illumina and Hi-C sequencing technologies in order to identify the genome differences between the A. cerana abansis and the published genomes of different A. cerana strains. The sequencing methods, assembly and annotation strategies of A. cerana abansis were more comprehensive than previously published A. cerana genomes. Then, the intraspecific genetic diversity of A. cerana was revealed at the genomic level. We re-identified the repeat content in the genome of A. cerana abansis, as well as the other three A. cerana strains. The chemosensory and immune-related proteins in different A. cerana strains were carefully re-identified, so that 132 odorant receptor subfamilies, 12 gustatory receptor subfamilies and 22 immune-related pathways were found. We also discovered that, compared with other published genomes, the A. ceranaabansis lost the largest number of chemoreceptors compared to other strains, and hypothesized that gene loss/gain might help different A. cerana strains to adapt to their respective environments. Our work contains more complete and precise assembly and annotation results for the A. cerana genome, thus providing a resource for subsequent in-depth related studies.

6.
Ultrason Sonochem ; 78: 105737, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34500313

RESUMO

The enhancement of the heat transfer assisted by ultrasound is considered to be an interesting and highly efficient cooling technology, but the investigation and application of ultrasound in minichannel heat sinks to strengthen the flow boiling heat transfer are very limited. Herein, a novel installation of ultrasound transducers in the flow direction of a minichannel heat sink is designed to experimentally study the characteristics of heat transfer in flow boiling and the influence of operation parameters (e.g., heat flux, mass flux rate) and ultrasound parameters (e.g., frequency, power) on the flow boiling heat transfer in a minichannel heat sink with and without ultrasound field. Bubble motion and flow pattern in the minichannel are analyzed by high-speed flow visualization, revealing that the ultrasound field induces more bubbles at the same observation position and a forward shift of the onset of nucleation boiling along the flow direction, as ultrasonic cavitation produces a large number of bubbles. Moreover, bubbles hitting the channel wall on the left and right sides are found, and the motion speed of the bubbles is increased by 31.9% under the ultrasound field. Our results demonstrate that the heat transfer coefficient obtained under the ultrasound field is 53.9% higher than in the absence of the ultrasound field under the same conditions, and the enhancement ratio is decreased in the high heat flux region due to the change of the flow regime with increasing heat flux. This study provides a theoretical basis for the application of an ultrasound field in minichannel heat sinks for the enhancement of flow boiling heat transfer.

7.
Opt Express ; 26(14): 18155-18163, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114095

RESUMO

The enhancement of light-matter interaction for monolayer graphene is of great importance on many photonic and optoelectronic applications. With the aim of perfect ultraviolet trapping on monolayer graphene, we adopt the design of an all-dielectric nanostructure, in which the magnetic resonance of optical field is combined with an ultraviolet mirror. The physics inside is revealed in comparison with the conventional plasmonic perfect absorber, and various influence factors of absorption bands are systematically investigated. In the ultraviolet range, an optimized absorbance ratio up to 99.7% is reached, which is 10 times more than that of the suspended graphene, and the absorption bands are linearly reconfigurable by angular manipulation of incident light. The scheme for perfect ultraviolet trapping in a sub-nanometer scale paves the way for developing more promising ultraviolet devices based on graphene and potentially other 2D materials.

8.
Medicine (Baltimore) ; 97(26): e11293, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29953011

RESUMO

Pancreatic lipidosis (nonalcoholic fatty pancreas disease, NAFPD) causes insulin resistance and dysfunction of pancreatic ß-cells, with the risk of type 2 diabetes mellitus (T2DM). However, the prevalence and pathogenic factors associated with NAFPD are not clear. The aim of the study was to explore the prevalence of NAFPD in a Chinese adult population, and investigate factors associated with NAFPD aggravation.This was a cross-sectional study; 4419 subjects were enrolled for NAFPD screening and were divided into NAFPD (n = 488) and without NAFPD (n = 3930) groups. The sex, age, related concomitant diseases, general physical parameters, and serum glucose and lipid metabolism were compared between the 2 groups.The overall NAFPD prevalence was 11.05%, but increased with age. In those <55 years NAFPD prevalence was lower in females than males (P < .05), but prevalence was similar >55 years. Nonalcoholic fatty liver disease (NAFLD), T2DM, homeostasis model assessment-insulin resistance index, total cholesterol, triglyceride, lipoprotein, adiponectin, and glucagon-like peptide 1 (GLP-1) were the independent risk factors for NAFPD (P < .05). Analaysis of mild NAFPD (MN) and severe NAFPD (SN) subgroups, according to the extent of fat deposition, suggested that NAFLD, triglyceride, lipoprotein, and adiponectin were independent risk factors for NAFPD aggravation (P < .05).The NAFPD prevalence was about 11% in Chinese adults. Its development and progression was related to NAFLD, T2DM, insulin resistance, dyslipidemia, and GLP-1 levels. Severe NAFPD was associated with NAFLD and dyslipidemia.


Assuntos
Pancreatopatias/epidemiologia , Pancreatopatias/patologia , Adiponectina/sangue , Adulto , Fatores Etários , China/epidemiologia , Comorbidade , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Dislipidemias/epidemiologia , Feminino , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Hipertensão/epidemiologia , Resistência à Insulina , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Pancreatopatias/sangue , Prevalência , Fatores de Risco , Fatores Sexuais , Triglicerídeos/sangue
9.
Opt Express ; 25(15): 17114-17127, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789207

RESUMO

A generalized random medium is introduced of which the effective radius and the correlation length are assumed to depend on the wavelength of the incident light. The generalized Stokes parameters of a random electromagnetic beam are employed to characterize the statistical properties of the far-zone scattered field generated by the introduced random medium. It is shown that the dependence of the effective radius and the correlation length of a medium on the wavelength can affect the behaviors of the intensity, coherence and polarization of the scattered field. Besides, the distributions of the scattered field are found to have many differences between the situations of medium-led modulation and beam-led modulation.

10.
Opt Express ; 23(25): 32318-28, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26699022

RESUMO

Modulating spatial near-infrared light for ultra-compact electro-optic devices is a critical issue in optical communication and imaging applications. To date, spatial near-infrared modulators based on graphene have been reported, but they showed limited modulation effects due to the relatively weak light-graphene interaction. In combination with graphene and metallic nanoslits, we design a kind of ultrathin near-infrared perfect absorber with enhanced spatial modulation effects and independence on a wide range of incident angles. The modulated spectral shift of central wavelength is up to 258.2 nm in the near-infrared range, which is more promising in applications than state-of-the-art devices. The modulation enhancement is attributed to the plasmonic nanoslit mode, in which the optical electric field is highly concentrated in the deep subwavelength scale and the light-graphene interaction is significantly strengthened. The physical insight is deeply revealed by a combination of equivalent circuit and electromagnetic field analysis. The design principles are not only crucial for spatial near-infrared modulators, but also provide a key guide for developing active near-infrared patch nanoantennas based on graphene.

11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 28(11): 1014-7, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19213346

RESUMO

OBJECTIVE: To study the effect of Jiangzhuo Mixture (JZM) on glucose and lipid metabolism, free fatty acid (FFA) and insulin sensitivity index of sodium glutamate (MSG) induced obese rats. METHODS: Sixty-four male MSG rats, 8-10 weeks old, were randomly divided into 4 groups equally, the low dose and high dose JZM group were treated respectively with 10 mL/(kg d) and 20 mL/(kg d) JZM, the rosiglitazone (RGZ) group with water solution of RGE 20 mg/(kg d), while the model group fed only with distilled water 10 mL/(kg d) for control, all by gastrogavage for 7 successive weeks. Levels of fasting blood glucose (FBG), triglyceride (TG), cholesterol (TC), and serum fasting insulin (Ins) were measured before and after treatment. Besides, the level of FFA and the proportion of fat weight to body weight (F/B) were measured and insulin sensitivity index (ISI) was calculated after treatment. RESULTS: After being treated for 7 weeks, the indexes including TC, FBG, Ins, F/B and FFA were all lower than those in the model group. Compared with before treatment, TC level lowered, FBG and Ins level raised in the two JZM groups and the RGZ group. Comparisons between the three treated group showed a significant lower level of Ins in the RGZ group. Level of ISI was significantly lowered in the 3 groups after treatment (P <0.05), but still higher in the RGZ group than that in the model control group (P <0.05). As for level of FFA, it was 314.81 +/- 110.25 micromol/L in the high dose JZM group and 305.56 +/- 92.33 micromol/L in the RGZ group, which were lower than that in the low dose JZM group (375.00 +/- 219.95 micromol/L, P <0.05). CONCLUSIONS: JZM could decrease the serum levels of TC, FBG, Ins and FFA in MSG rats, and decrease the fat content of organism in rats' growth process. The FFA decreasing action is dose-dependent. But its effect on ISI in MSG rats in the growth stage is insignificant. JZM can not reverse the forming processes of hyperglycemia, hyperinsulinemia, and insulin resistance in MSG rats.


Assuntos
Glicemia/efeitos dos fármacos , Medicamentos de Ervas Chinesas/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Animais , Modelos Animais de Doenças , Humanos , Masculino , Obesidade/induzido quimicamente , Obesidade/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Glutamato de Sódio/efeitos adversos
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