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1.
J Reprod Dev ; 69(6): 298-307, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-37779094

RESUMO

Dynamic changes in the endometrium are crucial for establishing early pregnancy in ruminants. Blastocyst elongation and implantation require hormones and nutrients to be secreted from the maternal endometrium. The fatty acid-binding protein FABP4 is a widely expressed fatty acid transport protein that promotes cell proliferation, migration, and invasion and is involved in conceptus implantation. However, the mechanism underlying the functional regulation of endometrial epithelial cells (EECs) by FABP4 during ovine peri-implantation remains unclear. We simulated hormonal changes in vitro in sheep EECs (SEECs) during the peri-implantation period and found that it elevated FABP4 expression. FABP4 inhibition significantly reduced cell migration, endoplasmic reticulum stress, and autophagy, suggesting that FABP4 regulates endometrial function in sheep. Moreover, the FABP4 inhibitor BMS309403 counteracted hormone-mediated functional changes in SEECs, and an endoplasmic reticulum stress activator and autophagy inhibitor reversed the abnormal secretion of prostaglandins induced by FABP4 inhibition. These results suggest that FABP4 affects ovine endometrial function during early gestation by regulating endoplasmic reticulum stress and autophagy in SEECs.


Assuntos
Endométrio , Estresse do Retículo Endoplasmático , Proteínas de Ligação a Ácido Graxo , Animais , Feminino , Gravidez , Autofagia/genética , Endométrio/metabolismo , Estresse do Retículo Endoplasmático/genética , Células Epiteliais/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Hormônios/metabolismo , Ovinos
2.
Opt Express ; 31(19): 30118-30129, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710561

RESUMO

Currently, mainstream light detection and ranging (LiDAR) systems usually involve a mechanical scanner component, which enables large-scale, high-resolution and multi-spectral imaging, but is difficult to assemble and has a larger system size. Furthermore, the mechanical wear on the moving parts of the scanner reduces its usage lifetime. Here, we propose a high-resolution scan-less multi-spectral three-dimensional (3D) imaging system, which improves the resolution with a four-times increase in the pixel number and can achieve multi-spectral imaging in a single snapshot. This system utilizes a specially designed multiple field-of-view (multi-FOV) system to separate four-wavelength echoes carrying depth and spectral reflectance information with predetermined temporal intervals, such that one single pixel of the SPAD array can sample four adjacent positions through the four channels' FOVs with subpixel offset. The positions and reflectivity are thus mapped to wavelengths in different time-bins. Our results show that the system can achieve high-resolution multi-spectral 3D imaging in a single exposure without scanning component. This scheme is the first to realize scan-less single-exposure high-resolution and multi-spectral imaging with a SPAD array sensor.

3.
Nanomaterials (Basel) ; 11(9)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34578606

RESUMO

Reducing the operating temperature of Solid Oxide Fuel Cells (SOFCs) to 300-600 °C is a great challenge for the development of SOFC. Among the extensive research and development (R&D) efforts that have been done on lowering the operating temperature of SOFCs, nanomaterials have played a critical role in improving ion transportation in electrolytes and facilitating electrochemical catalyzation of the electrodes. This work reviews recent progress in lowering the temperature of SOFCs by using semiconductor-ionic conductor nanomaterial, which is typically a composition of semiconductor and ionic conductor, as a membrane. The historical development, as well as the working mechanism of semiconductor-ionic membrane fuel cell (SIMFC), is discussed. Besides, the development in the application of nanostructured pure ionic conductors, semiconductors, and nanocomposites of semiconductors and ionic conductors as the membrane is highlighted. The method of using nano-structured semiconductor-ionic conductors as a membrane has been proved to successfully exhibit a significant enhancement in the ionic conductivity and power density of SOFCs at low temperatures and provides a new way to develop low-temperature SOFCs.

4.
Sci Rep ; 11(1): 920, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441649

RESUMO

Transformation acoustics, as an unconventional theory, provides a powerful tool to design various kinds of acoustic devices with excellent functionalities. However, the required ideal parameters, which are prescribed by the method, are both complex and hard to implement-even using acoustic metamaterials. Furthermore, simplified parameter materials are generally favored in transformation-acoustic design due to its easier realization with artificial structures. In this letter, we propose a coordinate transformation methodology for achieving simplified parameters by tuning the impedance distribution in the geometric limit, where the transformation media parameters can be derived by setting tunable impedance functions in the original space and a combination of suitable linear or nonlinear coordinate transformation. Based on this approach, both two-dimensional acoustic cloak and concentrators are designed with different sets of simplified parameters. Numerical simulations indicate good performance of these devices with minimized scattering at higher frequencies. The proposed method provides more opportunities to realize the designed acoustic devices experimentally, and can also be used for other transformation-acoustic designs including 3D cases.

5.
J Ethnopharmacol ; 265: 113228, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32777517

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The uses of medicinal plants have a long history and become one of the important sources of the health cares in Gaomi City, Shandong Province, China. However, limited studies have been done to identify these medicinal plant species and to scientifically document their associated traditional knowledge. Many species used by indigenous people could potentially represent a novel resource of medicine. The study can aid in further investigations of modern pharmacology and planning of the wild species conservation. AIM OF THE STUDY: The study aimed to investigate and record the medicinal plant taxa and their associated traditional knowledge in Gaomi City, China. MATERIALS AND METHODS: Field study was conducted from March 2018 to May 2019 with 184 residents of Gaomi City. Traditional medicinal plant specimens were collected from the field with the help of these residents and were identified and authenticated in the Herbarium of the School of Pharmacy, Binzhou Medical University. Ethnobotanical knowledge was collected by semi-structured face-to-face interviews. The quantitative data were analyzed by using the informant consensus factor (ICF) method and the number of citations. RESULTS: A total of 181 species belonging to 137 genera and 65 families were collected in Gaomi City. Asteraceae was the predominant family and Fabaceae took the second place. River basins and the southern hills in Gaomi were rich in vegetation. However, the cultivated area of medicinal plants only accounted for 10% of agricultural acreage. The main preparation method was decocting (170, 94.48%) and the most frequent mode of administration was oral (177, 97.97%). The highest numerical ICF value was recorded for treating endocrine, metabolic, and nutritional (ICF: 0.85) conditions. Seven of the medicinal plant species used by the people in Gaomi have not been reported previously in China. Verbena officinalis L. was found in Gaomi City, which is a new distribution record for this species. CONCLUSIONS: People in Gaomi hold valuable knowledge about the use of medicinal plants; however, their knowledge has not been comprehensively documented. The therapeutic uses of the documented medicinal plants will provide a basis for further pharmacological and phytochemical investigations. Additionally, the result of this study indicated that the elder people in Gaomi have more traditional knowledge of plant medicines than the younger ones.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Medicina Tradicional Chinesa/métodos , Plantas Medicinais/classificação , Adulto , Fatores Etários , Etnobotânica , Etnofarmacologia , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Front Microbiol ; 12: 813245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35154038

RESUMO

Altered gut microbiota are implicated in inflammatory neonatal calf diarrhea caused by E. coli K99. Beneficial probiotics are used to modulate gut microbiota. However, factors that mediate host-microbe interactions remain unclear. We evaluated the effects of a combination of multispecies probiotics (MSP) on growth, intestinal epithelial development, intestinal immune function and microbiota of neonatal calves infected with E. coli K99. Twelve newborn calves were randomly assigned as follows: C (control, without MSP); D (E. coli O78:K99 + gentamycin); and P (E. coli O78:K99 + supplemental MSP). All groups were studied for 21 d. MSP supplementation significantly (i) changed fungal Chao1 and Shannon indices of the intestine compared with group D; (ii) reduced the relative abundance of Bacteroides and Actinobacteria, while increasing Bifidobacteria, Ascomycetes, and Saccharomyces, compared with groups C and D; (iii) improved duodenal and jejunal mucosal SIgA and total Short Chain Fatty Acids (SCFA) concentrations compared with group D; (iv) increased relative ZO-1 and occludin mRNA expression in jejunal mucosa compared with group D; and (v) enhanced intestinal energy metabolism and defense mechanisms of calves by reducing HSP90 expression in E. coli K99, thereby alleviating the inflammatory response and promoting recovery of mucosal function. Our research may provide direct theoretical support for future applications of MSP in ruminant production.

7.
Sci Rep ; 8(1): 9091, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29904076

RESUMO

There is growing interest in designing waveguide couplers with low reflections. Using impedance-tunable transformation optics, we propose a coordinate transformation technique in the design of compact three-dimensional waveguide couplers. To transmit electromagnetic waves between two coaxial waveguides with different inner and outer radii in the microwave range, a suitable impedance function is derived to reduce the impedance mismatch at the boundary, which make the fabrication process being simplified due to the reduced set of transformation media(dielectric response materials only). A larger refractive index is set to raise the coupling performance in the low frequency range. Next we apply impedance-tunable transformation optics to the design of dielectric waveguide couplers, where only the core region be contained in the transformed space; by selecting a tunable impedance function, waves can transmit efficiently through waveguides with quite different cross sections and background media. The proposed impedance-tunable three-dimensional waveguide couplers are confirmed by the 3-dimensional numerical simulation with good performances, which can have potential applications in fiber-to-chip coupling.

8.
Phys Rev E ; 93(6): 062217, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27415265

RESUMO

We study a variable-coefficient nonlinear Schrödinger (vc-NLS) equation with higher-order effects. We show that the breather solution can be converted into four types of nonlinear waves on constant backgrounds including the multipeak solitons, antidark soliton, periodic wave, and W-shaped soliton. In particular, the transition condition requiring the group velocity dispersion (GVD) and third-order dispersion (TOD) to scale linearly is obtained analytically. We display several kinds of elastic interactions between the transformed nonlinear waves. We discuss the dispersion management of the multipeak soliton, which indicates that the GVD coefficient controls the number of peaks of the wave while the TOD coefficient has compression effect. The gain or loss has influence on the amplitudes of the multipeak soliton. We further derive the breather multiple births and Peregrine combs by using multiple compression points of Akhmediev breathers and Peregrine rogue waves in optical fiber systems with periodic GVD modulation. In particular, we demonstrate that the Peregrine comb can be converted into a Peregrine wall by the proper choice of the amplitude of the periodic GVD modulation. The Peregrine wall can be seen as an intermediate state between rogue waves and W-shaped solitons. We finally find that the modulational stability regions with zero growth rate coincide with the transition condition using rogue wave eigenvalues. Our results could be useful for the experimental control and manipulation of the formation of generalized Peregrine rogue waves in diverse physical systems modeled by vc-NLS equation with higher-order effects.

9.
Phys Rev E ; 93(1): 012214, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26871080

RESUMO

We study the nonlinear waves on constant backgrounds of the higher-order generalized nonlinear Schrödinger (HGNLS) equation describing the propagation of ultrashort optical pulse in optical fibers. We derive the breather, rogue wave, and semirational solutions of the HGNLS equation. Our results show that these three types of solutions can be converted into the nonpulsating soliton solutions. In particular, we present the explicit conditions for the transitions between breathers and solitons with different structures. Further, we investigate the characteristics of the collisions between the soliton and breathers. Especially, based on the semirational solutions of the HGNLS equation, we display the novel interactions between the rogue waves and other nonlinear waves. In addition, we reveal the explicit relation between the transition and the distribution characteristics of the modulation instability growth rate.

10.
Chaos ; 25(6): 063111, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26117105

RESUMO

In this paper, the nonautonomous Lenells-Fokas (LF) model is investigated. The modulational instability analysis of the solutions with variable coefficients in the presence of a small perturbation is studied. Higher-order soliton, breather, earthwormon, and rogue wave solutions of the nonautonomous LF model are derived via the n-fold variable-coefficient Darboux transformation. The solitons and earthwormons display the elastic collisions. It is found that the nonautonomous LF model admits the higher-order periodic rogue waves, composite rogue waves (rogue wave pair), and oscillating rogue waves, whose dynamics can be controlled by the inhomogeneous nonlinear parameters. Based on the second-order rogue wave, a diamond structure consisting of four first-order rogue waves is observed. In addition, the semirational solutions (the mixed rational-exponential solutions) of the nonautonomous LF model are obtained, which can be used to describe the interactions between the rogue waves and breathers. Our results could be helpful for the design of experiments in the optical fiber communications.

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