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1.
New Phytol ; 240(6): 2436-2454, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37840365

RESUMEN

Seed size and weight are important factors that influence soybean yield. Combining the weighted gene co-expression network analysis (WGCNA) of 45 soybean accessions and gene dynamic changes in seeds at seven developmental stages, we identified candidate genes that may control the seed size/weight. Among these, a PLATZ-type regulator overlapping with 10 seed weight QTLs was further investigated. This zinc-finger transcriptional regulator, named as GmPLATZ, is required for the promotion of seed size and weight in soybean. The GmPLATZ may exert its functions through direct binding to the promoters and activation of the expression of cyclin genes and GmGA20OX for cell proliferation. Overexpression of the GmGA20OX enhanced seed size/weight in soybean. We further found that the GmPLATZ binds to a 32-bp sequence containing a core palindromic element AATGCGCATT. Spacing of the flanking sequences beyond the core element facilitated GmPLATZ binding. An elite haplotype Hap3 was also identified to have higher promoter activity and correlated with higher gene expression and higher seed weight. Orthologues of the GmPLATZ from rice and Arabidopsis play similar roles in seeds. Our study reveals a novel module of GmPLATZ-GmGA20OX/cyclins in regulating seed size and weight and provides valuable targets for breeding of crops with desirable agronomic traits.


Asunto(s)
Glycine max , Transcriptoma , Glycine max/genética , Transcriptoma/genética , Fitomejoramiento , Sitios de Carácter Cuantitativo , Semillas/genética
2.
Opt Express ; 31(13): 21706-21720, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37381261

RESUMEN

This study investigates a low-loss and flexible terahertz frequency selective surface (FSS) based on cyclic olefin copolymer (COC) film substrate, which is fabricated via a simple temperature-control method without the use of solvent. The measured frequency response of the proof-of-concept COC-based THz bandpass FSS matches well with the numerical results. Due to the ultra-low COC dielectric dissipation factor (order of 0.0001) in the THz band, the measured passband insertion loss at 559 GHz reaches 1.22 dB, which is much better than that of previously reported THz bandpass filters. This work indicates that the remarkable characteristics (small dielectric constant, low frequency dispersion, low dissipation factor, good flexibility, etc.) of the proposed COC material make it a great application prospect in the THz field.

3.
J Integr Plant Biol ; 65(8): 1983-2000, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37066995

RESUMEN

Seed weight is usually associated with seed size and is one of the important agronomic traits that determine yield. Understanding of seed weight control is limited, especially in soybean plants. Here we show that Glycine max JASMONATE-ZIM DOMAIN 3 (GmJAZ3), a gene identified through gene co-expression network analysis, regulates seed-related traits in soybean. Overexpression of GmJAZ3 promotes seed size/weight and other organ sizes in stable transgenic soybean plants likely by increasing cell proliferation. GmJAZ3 interacted with both G. max RESPONSE REGULATOR 18a (GmRR18a) and GmMYC2a to inhibit their transcriptional activation of cytokinin oxidase gene G. max CYTOKININ OXIDASE 3-4 (GmCKX3-4), which usually affects seed traits. Meanwhile, the GmRR18a binds to the promoter of GmMYC2a and activates GmMYC2a gene expression. In GmJAZ3-overexpressing soybean seeds, the protein contents were increased while the fatty acid contents were reduced compared to those in the control seeds, indicating that the GmJAZ3 affects seed size/weight and compositions. Natural variation in JAZ3 promoter region was further analyzed and Hap3 promoter correlates with higher promoter activity, higher gene expression and higher seed weight. The Hap3 promoter may be selected and fixed during soybean domestication. JAZ3 orthologs from other plants/crops may also control seed size and weight. Taken together, our study reveals a novel molecular module GmJAZ3-GmRR18a/GmMYC2a-GmCKXs for seed size and weight control, providing promising targets during soybean molecular breeding for better seed traits.


Asunto(s)
Glycine max , Semillas , Glycine max/metabolismo , Fenotipo , Semillas/genética , Semillas/metabolismo , Perfilación de la Expresión Génica , Ácidos Grasos/metabolismo
4.
Opt Express ; 29(10): 14974-14984, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33985207

RESUMEN

Multi-functional metamaterial absorbers have attracted considerable attention for applications in the microwave frequency regime. In this paper, we report the design, fabrication, and characterization of frequency-selective absorbers, which exhibit substantial absorption property within a pre-defined frequency band, while at the same time behaving as a highly transparent screen in another targeted frequency band. The proposed designs consist of a symmetrically patterned indium tin oxide film acting as an absorbing layer, two dielectric substrates, and a cross-slot metal sheet frequency selective surface playing the role of a transmitting layer. In order to validate the functionalities of the designed absorbers, equivalent circuit models, full-wave numerical simulations and measurements are presented. The measured results, in good agreement with the numerical ones, show that the proposed designs realize 80% broadband absorption over the desired frequency range and possess a transparent window in a higher or lower frequency band for a wide range of incidence angles up to 60°. These performances suggest that the proposed designs are promising candidates for multi-functional scattering control and communication applications.

5.
Inorg Chem ; 56(5): 2379-2382, 2017 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-28217998

RESUMEN

A unique channel-type metal-organic framework (MOF) built up from mixed square-planar Co4(µ2-OH)4(µ4-OH) and cuboidal Co4(µ3-OH)4 clusters with an isonicotinic acid ligand has been successfully fabricated that demonstrates the highest specific surface area and high H2 uptake capacities among all of the cobalt(II) isonicotinic acid frameworks reported so far.

6.
Opt Express ; 24(9): 9629-44, 2016 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-27137576

RESUMEN

In this work, the design methodology and experimental investigation of compact and lightweight dispersive coatings, comprised by multiple layers of anisotropic metasurfaces, which are capable of cloaking radiators at multiple frequencies are presented. To determine the required surface electromagnetic properties for each layer, an analytical model is developed for predicting the scattering from a cylinder surrounded by multiple layers of anisotropic metasurfaces subject to plane-wave illumination at a general oblique incidence angle. Particularly, two different metasurface coating solutions with different dispersive properties are designed to provide more than 10 dB scattering width suppression at two pre-selected frequencies within a field-of-view (FOV) of ± 20° off normal incidence. Both coating designs implemented using metasurfaces are fabricated and measured, experimentally demonstrating the simultaneous suppression of mutual coupling and quasi-three-dimensional radiation blockage at the two pre-selected frequency ranges. At the same time, the functionality of the coated monopole is still well-maintained. The performance comparison further sheds light on how the optimal performance can be obtained by properly exploiting the dispersion of each metasurface layer of the coating. In addition, the cloaking effect is retained even when the distance between the radiators is significantly reduced. The concept and general design methodology presented here can be extended for applications that would benefit from cloaking multi-spectral terahertz as well as optical antennas.

7.
Philos Trans A Math Phys Eng Sci ; 373(2049)2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26217054

RESUMEN

Transformation optics provides scientists and engineers with a new powerful design paradigm to manipulate the flow of electromagnetic waves in a user-defined manner and with unprecedented flexibility, by controlling the spatial distribution of the electromagnetic properties of a medium. Using this approach, over the past decade, various previously undiscovered physical wave phenomena have been revealed and novel electromagnetic devices have been demonstrated throughout the electromagnetic spectrum. In this paper, we present versatile theoretical and experimental investigations on designing transformation optics-enabled devices for shaping electromagnetic wave radiation and guidance, at both radio frequencies and optical wavelengths. Different from conventional coordinate transformations, more advanced and versatile coordinate transformations are exploited here to benefit diverse applications, thereby providing expanded design flexibility, enhanced device performance, as well as reduced implementation complexity. These design examples demonstrate the comprehensive capability of transformation optics in controlling electromagnetic waves, while the associated novel devices will open up new paths towards future integrated electromagnetic component synthesis and design, from microwave to optical spectral regimes.

8.
Eur J Radiol ; 176: 111502, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38759544

RESUMEN

OBJECTIVE: To summary radiating blood flow signals and evaluate their diagnostic value in differentiating benign and malignant thyroid nodules. MATERIALS AND METHODS: We retrospectively recruited consecutive patients undergoing US at 4 hospitals from 2018 to 2022. In a training dataset, the correlations of US features with malignant thyroid nodules were assessed by multivariate logistic analysis. Multivariate logistic regression models involving the ACR TI-RADS score, radiating blood flow signals and their combination were built and validated internally and externally. The AUC with 95% asymptotic normal confidence interval as well as sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) with 95% exact binomial confidence intervals were calculated. RESULTS: Among 2475 patients (1818 women, age: 42.47 ± 11.57; 657 men, age: 42.16 ± 11.69), there were 3187 nodules (2342 malignant nodules and 845 benign nodules). Radiating blood flow signals were an independent risk factor for diagnosing thyroid carcinoma. In the training set, the AUC of the model using the combination of radiating blood flow signals and the ACR TI-RADS score (0.95 95 % CI: [0.94, 0.97]; P < 0.001) was significantly higher than that of the ACR TI-RADS model (0.91 [0.89, 0.93]). In the two internal validation sets and the external validation set, the AUCs of the combination model were 0.97 [0.96, 0.98], 0.92 [0.88, 0.96], and 0.91 [0.86, 0.95], respectively, and were all significantly higher than that of the ACR TI-RADS score (0.92 [0.90, 0.95], 0.86 [0.81, 0.91], 0.84 [0.79, 0.89]; P < 0.001). CONCLUSION: Radiating blood flow is a new US feature of thyroid carcinomas that can significantly improve the diagnostic performance vs. the ACR TI-RADS score.


Asunto(s)
Sensibilidad y Especificidad , Neoplasias de la Tiroides , Ultrasonografía , Humanos , Masculino , Femenino , Neoplasias de la Tiroides/diagnóstico por imagen , Adulto , Estudios Retrospectivos , Ultrasonografía/métodos , Diagnóstico Diferencial , Persona de Mediana Edad , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/irrigación sanguínea
9.
Adv Mater ; 36(26): e2402170, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38587064

RESUMEN

The rapid advancement of prevailing communication/sensing technologies necessitates cost-effective millimeter-wave arrays equipped with a massive number of phase-shifting cells to perform complicated beamforming tasks. Conventional approaches employing semiconductor switch/varactor components or tunable materials encounter obstacles such as quantization loss, high cost, high complexity, and limited adaptability for realizing large-scale arrays. Here, a low-cost, ultrathin, fast-response, and large-scale solution relying on metasurface concepts combined together with liquid crystal (LC) materials requiring a layer thickness of only 5 µm is reported. Rather than immersing resonant structures in LCs, a joint material-circuit-based strategy is devised, via integrating deep-subwavelength-thick LCs into slow-wave structures, to achieve constitutive metacells with continuous phase shifting and stable reflectivity. An LC-facilitated reconfigurable metasurface sub-system containing more than 2300 metacells is realized with its unprecedented comprehensive wavefront manipulation capacity validated through various beamforming functions, including beam focusing/steering, reconfigurable vortex beams, and tunable holograms, demonstrating a milli-second-level function-switching speed. The proposed methodology offers a paradigm shift for modulating electromagnetic waves in a non-resonating broadband fashion with fast-response and low-cost properties by exploiting functionalized LC-enabled metasurfaces. Moreover, this extremely agile metasurface-enabled antenna technology will facilitate a transformative impact on communication/sensing systems and empower new possibilities for wavefront engineering and diffractive wave calculation/inference.

10.
Cell Death Dis ; 15(2): 158, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383528

RESUMEN

Chemotherapy is a primary treatment for esophageal squamous cell carcinoma (ESCC). Resistance to chemotherapeutic drugs is an important hurdle to effective treatment. Understanding the mechanisms underlying chemotherapy resistance in ESCC is an unmet medical need to improve the survival of ESCC. Herein, we demonstrate that ferroptosis triggered by inhibiting high mobility group AT-hook 1 (HMGA1) may provide a novel opportunity to gain an effective therapeutic strategy against chemoresistance in ESCC. HMGA1 is upregulated in ESCC and works as a key driver for cisplatin (DDP) resistance in ESCC by repressing ferroptosis. Inhibition of HMGA1 enhances the sensitivity of ESCC to ferroptosis. With a transcriptome analysis and following-up assays, we demonstrated that HMGA1 upregulates the expression of solute carrier family 7 member 11 (SLC7A11), a key transporter maintaining intracellular glutathione homeostasis and inhibiting the accumulation of malondialdehyde (MDA), thereby suppressing cell ferroptosis. HMGA1 acts as a chromatin remodeling factor promoting the binding of activating transcription factor 4 (ATF4) to the promoter of SLC7A11, and hence enhancing the transcription of SLC7A11 and maintaining the redox balance. We characterized that the enhanced chemosensitivity of ESCC is primarily attributed to the increased susceptibility of ferroptosis resulting from the depletion of HMGA1. Moreover, we utilized syngeneic allograft tumor models and genetically engineered mice of HMGA1 to induce ESCC and validated that depletion of HMGA1 promotes ferroptosis and restores the sensitivity of ESCC to DDP, and hence enhances the therapeutic efficacy. Our finding uncovers a critical role of HMGA1 in the repression of ferroptosis and thus in the establishment of DDP resistance in ESCC, highlighting HMGA1-based rewiring strategies as potential approaches to overcome ESCC chemotherapy resistance. Schematic depicting that HMGA1 maintains intracellular redox homeostasis against ferroptosis by assisting ATF4 to activate SLC7A11 transcription, resulting in ESCC resistance to chemotherapy.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Ferroptosis , Animales , Ratones , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/genética , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proteína HMGA1a/genética , Resistencia a Antineoplásicos/genética , Ferroptosis/genética , Proteína HMGA1b , Línea Celular Tumoral
11.
Opt Express ; 21(5): 5594-605, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23482132

RESUMEN

In this work, we propose an efficient approach to compensate for the commonly observed substrate-induced bianisotropy that occurs in on-wafer optical metamaterials at normal incidence. First, the consequence of placing a finite thickness substrate underneath a metamaterial is analyzed, indicating that the induced bianisotropy is a near-field effect. The properties of metamaterials sandwiched between an infinitely thick substrate and a finite-thickness superstrate with different permittivity and thickness values are then investigated. It is demonstrated from full-wave simulations that by adding an ultrathin superstrate with a judicious choice of its thickness and permittivity value, the substrate-induced bianisotropy of the system can be suppressed and even eliminated. In addition to the extracted nonlocal effective medium parameters, the induced electric and magnetic dipole moments calculated from the volumetric microscopic fields are also presented, validating that the magnetoelectric coupling compensation is a real physical phenomenon. This study will benefit future optical metamaterial design and implementation strategies as well as the corresponding fabrication and characterization methodologies.

12.
Opt Express ; 21(25): 31492-505, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24514723

RESUMEN

In this work, we present the design, numerical experiments, and analysis of a plasmonic metamaterial thin film based on subwavelength nano-notch loaded modified fishnet structures. The resulting device offers a simultaneous bandpass filtering functionality with a broad enhanced optical transmission window and a gapless negative-zero-positive index transition to enable polarization-independent passive beam-steering. This unique characteristic is made possible by the introduced subwavelength nano-notches, which provide fine tuning and hybridization of the external and internal surface plasmon polariton modes. This allows tailoring of the dispersive properties of the plasmonic metamaterial for broadband operation. Specifically, a multilayer nanostructured modified fishnet with feature sizes accessible by modern nanofabrication techniques is presented, exhibiting a broad passband at the mid-infrared wavelengths from 3.0 to 3.7 µm and stopbands elsewhere in the 2.5 ~4.5 µm window. The transmittance normalized to area is around 3 dB within the broad 20% bandwidth of the passband. Additionally, the effective index undergoes a smooth transition from negative unity through zero to positive unity with low loss within the passband. The physical mechanism and the angular dispersion of the metamaterial are analyzed in detail. Finally, full-wave simulations of a prism formed from this metamaterial are performed to demonstrate that the proposed structure achieves simultaneous polarization-insensitive passive beam-steering and filtering functionalities.

13.
World J Surg ; 37(6): 1362-70, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23456227

RESUMEN

BACKGROUND: The aim of this study was to compare the results of surgical resection with three-dimensional conformal radiotherapy (3D-CRT) in the treatment of resectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Transarterial chemoembolization (TACE) was given to both groups of patients when possible. METHODS: A retrospective study of 371 patients with resectable HCC with PVTT was conducted in two tertiary referral centers. The treatment of choice for these patients in one center was surgical resection. In the other center it was 3D-CRT. In the radiotherapy group (RG, n = 185), patients received 3D-CRT to the tumor and PVTT for a total radiation dose of 30-52 Gy (median 40 Gy). In the surgical group (SG, n = 186), patients underwent surgical resection. TACE was applied after surgery or 3D-CRT and then was repeated every 4-6 weeks if the patient tolerated the treatment. RESULTS: The median survival was 12.3 months for RG and 10.0 months for SG. The 1-, 2-, and 3-year overall survivals were 51.6, 28.4, and 19.9 %, respectively, for RG and 40.1, 17.0, and 13.6 %, respectively, for SG (p = 0.029). Stepwise multivariate analysis showed that the extent of PVTT and mode of treatment were independent risk factors of overall survival. The most common cause of death after treatment was liver failure as a consequence of progressive intrahepatic disease. CONCLUSIONS: 3D-CRT gave better survival than surgical resection for HCC with PVTT.


Asunto(s)
Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Vena Porta/patología , Trombosis/patología , Trombosis/terapia , Quimioembolización Terapéutica , Terapia Combinada , Femenino , Hepatectomía/métodos , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Radioterapia Conformacional , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
14.
Int J Ophthalmol ; 16(7): 1110-1116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37465504

RESUMEN

AIM: To determine the incidence and predictive factors for epiretinal membrane (ERM) formation in eyes with complicated primary rhegmatogenous retinal detachment (RRD) tamponaded with silicone oil (SO). METHODS: This retrospective case-control study included 141 consecutive patients with (51 eyes) and without (90 eyes) ERM formation after primary pars plana vitrectomy (PPV) and SO tamponade for complicated RRD. The risk factors for ERM were assessed using logistic regression analysis. RESULTS: The prevalence of postoperative ERM was 36.2% (51/141). Multivariate logistic regression analysis showed that the risk factors for ERM in SO-tamponaded eyes included preoperative proliferative vitreoretinopathy [PVR; odds ratio (OR), 2.578; 95% confidence interval (CI) 1.580-4.205, P<0.001], preoperative choroidal detachment (OR, 4.454; 95%CI 1.369-14.498, P=0.013), and photocoagulation energy (OR, 2.700; 95%CI 1.047-6.962, P=0.040). The duration of the preoperative symptoms, intraocular SO tamponade time, giant retinal tear, preoperative vitreous hemorrhage, preoperative best-corrected visual acuity, number of breaks, quadrants of RRD, axial length, and photocoagulation points were not predictive factors for ERM formation. CONCLUSION: Preoperative PVR, choroidal detachment, and photocoagulation energy are risk factors of ERM formation after complicated RRD repair. Better ophthalmic care as well as patient education are necessary for such patients with risk factors.

15.
Nat Commun ; 13(1): 7196, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36418286

RESUMEN

Identifying, quantifying, and suppressing decoherence mechanisms in qubits are important steps towards the goal of engineering a quantum computer or simulator. Superconducting circuits offer flexibility in qubit design; however, their performance is adversely affected by quasiparticles (broken Cooper pairs). Developing a quasiparticle mitigation strategy compatible with scalable, high-coherence devices is therefore highly desirable. Here we experimentally demonstrate how to control quasiparticle generation by downsizing the qubit, capping it with a metallic cover, and equipping it with suitable quasiparticle traps. Using a flip-chip design, we shape the electromagnetic environment of the qubit above the superconducting gap, inhibiting quasiparticle poisoning. Our findings support the hypothesis that quasiparticle generation is dominated by the breaking of Cooper pairs at the junction, as a result of photon absorption by the antenna-like qubit structure. We achieve record low charge-parity switching rate (<1 Hz). Our aluminium devices also display improved stability with respect to discrete charging events.

17.
Opt Express ; 18(1): 244-52, 2010 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-20173844

RESUMEN

The transformation optics technique for designing novel electromagnetic and optical devices offers great control over wave behavior, but is difficult to implement primarily due to limitations in current metamaterial design and fabrication techniques. This paper demonstrates that restricting the spatial transformation to a conformal mapping can lead to much simpler material parameters for more practical implementation. As an example, a flat cylindrical-to-plane-wave conversion lens is presented and its performance validated through numerical simulations. It is shown that the lens dimensions and embedded source location can be adjusted to produce one, two, or four highly directive planar beams. Two metamaterial designs for this lens that implement the required effective medium parameters are proposed and their behavior analyzed.


Asunto(s)
Materiales Manufacturados , Modelos Teóricos , Dispositivos Ópticos , Refractometría/instrumentación , Transductores , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Dispersión de Radiación
18.
Adv Mater ; 32(6): e1903983, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31879999

RESUMEN

Cylindrical vector vortex beams, a particular class of higher-order Poincaré sphere beams, are generalized forms of waves carrying orbital angular momentum with inhomogeneous states-of-polarization on their wavefronts. Conventional methods as well as the more recently proposed segmented/interleaved shared-aperture metasurfaces for vortex beam generation are either severely limited by bulky optical setups or by restricted channel capacity with low efficiency and mode number. Here, a noninterleaved vortex multiplexing approach is proposed, which utilizes superimposed scattered waves with opposite spin states emanating from all meta-atoms in a coherent manner, counter-intuitively enabling ultrahigh-capacity, high-efficiency, and flexible generation of massive vortex beams with structured state-of-polarization. A series of exemplary prototypes, implemented by sub-wavelength-thick metasurfaces, are demonstrated experimentally, achieving kaleidoscopic vector vortex beams. This methodology holds great promise for structured wavefront shaping, vortex generation, and high information-capacity planar photonics, which may have a profound impact on transformative technological advances in fields including spin-Hall photonics, optical holography, compressive imaging, electromagnetic communication, and so on.

19.
Artículo en Inglés | MEDLINE | ID: mdl-30805019

RESUMEN

Salidroside, a phenyl-propanoid glycoside isolated from the medicinal plant Rhodiola rosea, has potent cardioprotective effects, especially against myocardial hypoxia and reoxygenation injury. However, the molecular mechanism underlying its action is still unclear. The aim of this study was to determine the effect of salidroside on sodium channel current (INa) and transient outward potassium channel current (Ito) in H9C2 cardiomyocytes. H9C2 cells were subcultured under anoxic conditions to mimic myocardial hypoxia and subsequently treated with salidroside. Whole cell patch clamp was performed to determine the effect of hypoxia/reoxygenation and salidroside on myocardial electrophysiological properties. In the differentiated H9C2 cells, hypoxia/reoxygenation reduced INa and Ito amplitude, while salidroside significantly restored both and altered the INa and Ito activation/inactivation kinetics in a dose-dependent manner. Our findings demonstrate that salidroside protects myocardial cells against hypoxia-reoxygenation by restoring the function of sodium and potassium channels.

20.
Nat Commun ; 10(1): 108, 2019 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-30631069

RESUMEN

Nearly two decades of intense study have passed since the term metamaterials was first introduced in 1999. In spite of their great promise, however, metamaterials have been slow to find their way into practical devices, and examples of real-world applications remain rare. In this paper, an Advanced Short Backfire Antenna (A-SBFA), augmented with anisotropic metamaterial surfaces (metasurfaces), has been designed to achieve a very high aperture efficiency across two frequency bands. This performance is unprecedented for an antenna that has seen widespread use, but few design changes over its more than 50 year existence. The reduced weight, compact design, hexagonal aperture, high dual-band efficiency, high cross-polarization isolation, as well as low multipaction and passive intermodulation (PIM) risk make the A-SBFA ideal for spaceborne applications. This transformative design demonstrates how practical metamaterials, when applied to conventional antenna technology, can provide significant performance enhancements.

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