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1.
Opt Express ; 31(14): 23106-23114, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37475403

RESUMEN

The physical dimension of orbital angular momentum (OAM) states of light has been successfully implemented as information carrier in wireless optical communication (WOC) links. However, the current OAM data coding strategies in WOC are mainly limited to the temporal domain, rarely involving the degree of freedom of spatial domain to transmit an image directly. Here, we apply OAM holographic multiplexing technology for spatial information encoding in WOC links. Further, we demonstrate the new concept of OAM holographic multicasting, wherein a beam-steering grating has been utilized for information decoding. To distribute the OAM multiplexing information appropriately in the receiving terminal, the beam-steering grating with controllable topological charges and amplitude weighting coefficients of each diffraction order in the spatial frequency domain has been designed. An iterative algorithm has been introduced to obtain the intensity uniformity >98% at target diffraction orders. As such, this scheme experimentally allows four separate users to receive independent images, which can be switched by modulating the topological charges of the beam-steering gratings at each diffraction order. In addition, this leads to a beam-steering grating-encrypted WOC links, wherein the information can only be decoded by the grating phase with 7 pre-set spatial frequency components. Our results mark a new parallel decoding paradigm of OAM multiplexing holography, which opens up the door for future high-capacity and high-security all-optical holographic communications.

2.
Opt Express ; 29(13): 19807-19818, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34266083

RESUMEN

Beyond orbital angular momentum of Laguerre-Gaussian (LG) modes, the radial index can also be exploited as information channel in free-space optical (FSO) communication to extend the communication capacity, resulting in the LG- shift keying (LG-SK) FSO communications. However, the recognition of radial index is critical and tough when the superposed high-order LG modes are disturbed by the atmospheric turbulences (ATs). In this paper, the convolutional neural network (CNN) is utilized to recognize both the azimuthal and radial index of superposed LG modes. We experimentally demonstrate the application of CNN model in a 10-meter 768-ary LG-SK FSO communication system at the AT of Cn2 = 1e-14 m-2/3. Based on the high recognition accuracy of the CNN model (>95%) in the scheme, a colorful image can be transmitted and the peak signal-to-noise ratio of the received image can exceed 35 dB. We anticipate that our results can stimulate further researches on the utilization of the potential applications of LG modes with non-zero radial index based on the artificial-intelligence-enhanced optoelectronic systems.

3.
Nanotechnology ; 31(17): 175401, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31899895

RESUMEN

The increasing demand in energy consumption and the use of clean energy from sustainable energy sources have driven the research in the development of advanced materials for Li-ion and Na-ion batteries. In this work, we have developed a simple technique to synthesize a porous Sb structure through a galvanic replacement reaction between Sb3+ and Zn particles. The porous Sb structure consists of a three-dimensional-hierarchical structure with tree-like nanoscale Sb dendrites. The Sb in the nanodendrites is crystal of a rhombohedral structure. We construct Li-/Na-ion half cells and Li-/Na-ion full cells with the Sb nanodendrites as the active material in the working electrode and anode, respectively, and introduce an additive of vinylene carbonate for the Li-ion half/full cells and an additive of fluoroethylene carbonate for the Na-ion half/full cells. All the Li-/Na-ion half cells and Li-/Na-ion full cells exhibit excellent electrochemical performance and cycling stability. Such excellent performance can be attributed to the synergistic interaction between the three-dimensional-dendritic structure and electrolyte, which likely ensures fast transport of ions and electrons and the formation of a stable solid-state interphase.

4.
Nanotechnology ; 31(13): 135404, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-31810067

RESUMEN

There is a great need to develop sustainable and clean energy storage devices and systems of high-energy and high-capacity densities. In this work, we synthesize antimony (Sb) nanocrystal-anchored hollow carbon microspheres (Sb@HCMs) via the calcination of cultivated yeast cells and the reduction of SbCl3 in an ethylene glycol solution on the surface of hollow carbon microspheres. The Sb@HCMs possess hollow and porous structure, and the Sb is present in the form of nanocrystals. Using the Sb@HCMs as the active-electrode material, we assemble lithium (Li)-ion half cells and full cells and investigate their electrochemical performance. The Li-ion half cells possess a charge capacity of 605 mA h g-1 after 100 cycles at a current density of 100 mA g-1 and a charge capacity of 469.9 mA h g-1 at a current density up to 1600 mA g-1, which is much higher than the theoretical capacity of 372 mA h g-1 for commercial graphite electrode. The Li-ion full cells with Sb@HCMs//LiCoO2 deliver a charge capacity of 300 mA h g-1 at a current density of 0.2 A g-1 after 50 cycles, and have potential in applications of energy storage.

5.
Chem Biodivers ; 16(12): e1900431, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31609078

RESUMEN

A series of aminothiazole derivatives bearing the benzimidazole moiety were synthesized and evaluated in Gli luciferase reporter assays. Lead optimization led to the discovery of potent hedgehog pathway antagonist 18 (2-[3-(1H-benzimidazol-2-yl)-4-chloroanilino]-N-[4-(trifluoromethyl)phenyl]-1,3-thiazole-4-carboxamide), with IC50 values in nanomolar range. The molecular basis ascribed to hindering sonic hedgehog-driven Smoothened (Smo) localization within the primary cilium (PC). Moreover, compound 18 inhibited Gli1 mRNA expression in mutant Smo cell line and displayed moderate cytotoxicity against DAOY cancer cell.


Asunto(s)
Proteínas Hedgehog/metabolismo , Tiazoles/química , Anilidas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Proteínas Hedgehog/química , Ratones , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Tiazoles/síntesis química , Tiazoles/farmacología
6.
ACS Appl Mater Interfaces ; 16(4): 4708-4718, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38231566

RESUMEN

Sodium metal batteries (SMBs) have high-density and cost-effective characteristics as one of the energy storage systems, but uncontrollable dendrite growth and poor rate performance still hinder their practical applications. Herein, a nitrogen-rich modified cellulose separator with released abundant ion transport tunnels in organic electrolyte was synthesized by in situ polymerization of polypyrrole, which is based on the high permeability of cellulose in aqueous solution and the interfacial interaction between cellulose and polypyrrole. Meanwhile, the introduction of abundant structural defects such as branch chains, oxygen-containing functional groups, and imine-like structure to disrupt polypyrrole conjugation enables the utilization of conductive polymers in composite separator applications. With the electrolyte affinity surface on, the modified separator exhibits reinforced electrolyte uptake (254%) and extended electrolyte wettability, thereby leading to accelerated ionic conductivity (2.77 mS cm-1) and homogeneous sodium deposition by facilitating the establishment of additional pathways for ion transport. Benefiting from nitrogen-rich groups, the polypyrrole-modified separator demonstrates selective Na+ transport by the data of improved Na+ transference number (0.62). Owing to the above advantages, the battery assembled with the modified separators exhibits outstanding rate performance and prominent capacity retention two times that of the pristine cellulose separator at a high current density under the condition of fluorine-free electrolyte.

7.
ACS Appl Mater Interfaces ; 16(39): 52559-52571, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39301966

RESUMEN

Researchers are paying more attention to sodium-ion batteries (SIBs) because of their abundant supply of sodium resources and affordable price. TiO2 offers excellent safety and a long lifespan as an anode material for SIBs. However, the process kinetics is slow due to its limited Na+ storage efficiency, weak conductivity, and irreversible Na+ capture. In order to address these issues, this review uses a mix of the template approach and the double-hydrolysis method to manage the structure and diffusion of TiO2-based anode materials by synthesizing FeTiO3/TiO2 heterostructured double-shell microspheres (FTO). Through the built-in electric field effect caused by their heterostructures, FTO materials improve reaction kinetics, boost electronic conductivity, and lower the diffusion energy barrier of Na+. Their distinctive double-shell structure can increase electrolyte infiltration, shorten the diffusion distance between ions and electrons, and accommodate volume expansion during cycling. Furthermore, the irreversible capture of Na+ and the unfavorable interactions between the surface active site and electrolyte can be successfully inhibited by FTO heterostructures. FTO has an exceptionally high capacity (reaching 362.7 mA h g-1 after 60 cycles at 20 mA g-1) and excellent cycle stability (with a decay rate of 0.0061% after 1000 cycles at 2 A g-1). The strategy of constructing heterogeneous interfaces assists with high-performance SIB anode design.

8.
ACS Appl Mater Interfaces ; 16(32): 43026-43037, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39093713

RESUMEN

The aqueous zinc-ion batteries (ZIBs) have gained increasing attention because of their high specific capacity, low cost, and good safety. However, side reactions, hydrogen evolution reaction, and uncontrolled zinc dendrites accompanying the Zn metal anodes have impeded the applications of ZIBs in grid-scale energy storage. Herein, the poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires as an interfacial layer on the Zn anode (Zn-PEDOT) are reported to address the above issues. Our experimental results and density functional theory simulation reveal that the interactions between the Zn2+ and S atoms in thiophene rings of PEDOT not only facilitate the desolvation of hydrated Zn2+ but also can regulate the diffusion of Zn2+ along the thiophene molecular chains and induce the dendrite-free deposition of Zn along the (002) surface. Consequently, the Zn||Cu-PEDOT half-cell exhibits highly reversible plating/stripping behavior with an average Coulombic efficiency of 99.7% over 2500 cycles at 1 mA cm-2 and a capacity of 0.5 mAh cm-2. A symmetric Zn-PEDOT cell can steadily operate over 1100 h at 1 mA cm-2 (1 mAh cm-2) and 470 h at 10 mA cm-2 (2 mAh cm-2), outperforming the counterpart bare Zn anodes. Besides, a Zn-PEDOT||V2O5 full cell could deliver a specific capacity of 280 mAh g-1 at 1 A g-1 and exhibits a decent cycling stability, which are much superior to the bare Zn||V2O5 cell. Our results demonstrate that PEDOT nanowires are one of the promising interfacial layers for dendrite-free aqueous ZIBs.

9.
Clin Cosmet Investig Dermatol ; 17: 1527-1541, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948922

RESUMEN

Purpose: This study seeks to investigate the effect of evodiamine on psoriasis and psoriatic pruritus. Methods: Imiquimod-induced psoriasiform dermatitis in mice was used as a model, and evodiamine was topically applied for seven days. The mice were observed daily for skin damage on the back, clinical score and their scratching behavior was recorded. Blood samples were collected on the final day of the experiment, and the serum levels of pruritus-associated inflammatory cytokines tumor necrosis factor (TNF) -α, interleukin (IL) -23, and IL-17A were measured using enzyme-linked immunosorbent assay. Histopathological changes were observed in Hematoxylin and Eosin-stained skin specimens. The expression levels of transient receptor potential vanilloid (TRPV) 1, TRPV3, TRPV4, and the pruritus-related mediators Substance P (SP), nerve growth factor (NGF), and calcitonin gene-related peptide (CGRP) in the skin lesions were analyzed using Western blot and qRT-PCR. The effect of evodiamine on the exploratory behavior, motor, and coordination abilities of mice was assessed using open field, suspension, and Rota-Rod experiments. Molecular docking was utilized to verify the binding of evodiamine to the residues of TRPV1, TRPV3, and TRPV4. Results: Evodiamine reduced pruritus and inhibited inflammation by decreasing the levels of inflammatory mediators TNF-α, IL-23, and IL-17A in the serum of Imiquimod-induced mice and attenuated the mRNA and protein expression levels of SP, NGF, CGRP, TRPV1, TRPV3, and TRPV4 in the skin. Conclusion: Evodiamine is an effective treatment for psoriasis and pruritus, due to its ability to inhibit immune inflammation and pruritic mediators.

10.
Cell Death Dis ; 15(8): 590, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138151

RESUMEN

UBE2M, a NEDD8-conjugating enzyme, is dysregulated in various human cancers and promotes tumor cell proliferation. However, its role in estrogen receptor-positive (ER+) breast cancer remains unknown. We found that UBE2M expression was significantly higher in ER+ breast cancer tissues than in ER-negative (ER-) breast cancer tissues. Higher expression of UBE2M indicated a poorer prognosis in patients with ER+ breast cancer but not in those with ER- breast cancer. Of interest, a positive feedback loop was observed between UBE2M and ERα. Specifically, ERα enhanced the HIF-1α-mediated transcription of UBE2M. In turn, UBE2M maintained ERα expression by inhibiting its ubiquitination and degradation through UBE2M-CUL3/4A-E6AP-ERα axis. Functionally, silencing of UBE2M suppressed the growth of breast cancer cells by inducing cell cycle arrest and apoptosis and improved their sensitivity to fulvestrant both in vitro and in vivo. Altogether, our findings reveal that the UBE2M-ERα feedback loop drives breast cancer progression and fulvestrant resistance, suggesting UBE2M as a viable target for endocrine therapy of ER+ breast cancer.


Asunto(s)
Neoplasias de la Mama , Resistencia a Antineoplásicos , Receptor alfa de Estrógeno , Retroalimentación Fisiológica , Enzimas Ubiquitina-Conjugadoras , Humanos , Enzimas Ubiquitina-Conjugadoras/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Resistencia a Antineoplásicos/efectos de los fármacos , Receptor alfa de Estrógeno/metabolismo , Animales , Progresión de la Enfermedad , Ratones Desnudos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ratones , Apoptosis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Fulvestrant/farmacología , Ubiquitinación , Células MCF-7
11.
Adv Mater ; 35(30): e2301376, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37080909

RESUMEN

Titanates have been widely reported as anode materials for sodium-ion batteries (SIBs). However, their wide temperature suitability and cycle life remain fundamental issues that hinder their practical application. Herein, a novel hollow Na2 Ti3 O7 microsphere (H-NTO) with a unique chemically bonded NTO/C(N) interface is reported. Theoretical calculations demonstrated that the NTO/C(N) interface stabilizes the crystal structure, and the optimized interface enables the H-NTO anode to stably operate for 80 000 cycles in a conventional ester electrolyte with negligible capacity loss. Optimizing the electrolyte allows the H-NTO electrode to cycle stably for 200 calendar days without capacity degradation at -40 °C. The excellent cycling stability is attributed to the NTO/C(N) interface and the stable solid electrolyte interphase formed by the highly adaptable electrolyte/electrode interface. Titanate exhibits solvent co-intercalation behavior in ether-based electrolytes, and its robust structure ensures that it can adapt to large volume changes at low temperatures. This study provides a unique perspective on the long-cycle mechanism of titanate anodes and highlights the critical importance of manipulating the interfacial chemistry in SIBs, including the material and electrode/electrolyte interfaces.

12.
ACS Appl Mater Interfaces ; 13(37): 44214-44223, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34519201

RESUMEN

The sluggish sodium-ion diffusion kinetics and low electronic conductivity have severely restricted the development of the TiO2 anode for sodium-ion batteries. Defect engineering, such as single-heteroatom doping and oxygen vacancies, has proven to be effective methods to improve the conductivity of TiO2, but a comprehensive understanding of the synergistic effect of dual-heteroatom doping and oxygen vacancies on the sodium storage performance of TiO2 is still lacking. Herein, we design a synergistic strategy of dual doping via the in situ doping and hydrogenation treatment to improve conductivity and cycling stability of TiO2. Experiments and theoretical calculations together revealed that N and C doping reduces the band gap of TiO2, while the presence of oxygen vacancies efficiently accelerates the diffusion of sodium ions. Thus N, C, and oxygen vacancies with high concentration co-doped TiO2, resulting in extraordinary high-rate performance, significant stable cycling, and long-term cyclability of up to 10,000 cycles. The synthesis strategy of dual doping proposed here emphasizes the importance of defect engineering in improving material conductivity and electrode cycling stability for possible practical applications in the near future.

13.
ACS Appl Bio Mater ; 2(11): 4747-4755, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-35021475

RESUMEN

A drug delivery system based on the palladium and manganese dioxide composite (FP-Pd@MnO2) is designed and prepared for the first time. The FP-Pd@MnO2 allows doxorubicin (DOX) loading as high as 58% in weight. The rapid release of DOX from FP-Pd@MnO2 is regulated via pH reduction, ascending glutathione concentration, and near-infrared (NIR) stimulus, which is advantageous to control drug release in the tumor site. The photothermal effect of FP-Pd@MnO2 with wide and strong NIR optical absorbance is positively correlated with its concentration. As irradiated with an 808 nm laser, MDA-MB-231 cells and its tumor on mice with FP-Pd@MnO2/DOX administration are significantly suppressed, corroborating the preferable curative effect of combined photothermal therapy and chemotherapy with this agent.

14.
Phytochemistry ; 162: 183-192, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30928888

RESUMEN

Six undescribed Lycopodium alkaloids (LAs) comprising four lycodine-type (lycofargesiines A-D), one lycopodine-type (lycofargesiine E), and a phlegmarine-type (lycofargesiine F), together with 16 known ones were isolated from the club moss Huperzia fargesii. Their structures and absolute configurations were determined by extensive spectroscopic methods, electronic circular dichroism (ECD) analysis, and density functional theory (DFT) calculations. (7S,8R,12R,13R)-Lycofargesiine A is a rare naturally occurring LA possessing an exocyclic double bond between C-15 and C-16, with ring A being a rare 2,3-dihyropyridone motif. Lycofargesiine D is an uncommon lycodine-type alkaloid featuring a unique N-acetylated tetrahydropyridinyl segment (ring A), whereas lycofargesiine F is the first phlegmarane-type LA bearing two nitrone moieties. In addition to the isolated huperzine A in this study, another two isolates (lycofargesiine C and 16-hydroxyhuperzine A) were also found to show inhibitory activities against acetylcholinesterase (AChE), with IC50 values of 8.63 and 5.18 µM, respectively.


Asunto(s)
Alcaloides/química , Inhibidores de la Colinesterasa/química , Lycopodium/química , Alcaloides/farmacología , Inhibidores de la Colinesterasa/farmacología , Modelos Moleculares , Conformación Molecular
16.
Mater Sci Eng C Mater Biol Appl ; 80: 174-179, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28866153

RESUMEN

This study was dedicated to develop a nonenzymatic glucose sensor based on Ag&Pt hollow nanoparticles supported on TiO2 nanotubes. The Ag&Pt-TiO2/(500°C) was synthesized by a simple reduction and galvanic replacement method in an aqueous solution. The surface morphology and structure of Ag&Pt-TiO2/(500°C) could be examined by transmission electron microscopy, scanning electron microscopy and energy dispersive spectrometer. The mechanical behavior was measured by nanoindentation test and the hydropathy property was measured by contact angle test. It can be observed that Ag&Pt hollow structures with a particle size of 100nm and a wall thickness of 27nm were deposited on TiO2 nanotubes. The electrochemical properties were investigated by Electrochemical Workstation with three-electrode system. Ag&Pt(6h)-TiO2/(500°C) electrode exhibited excellent catalytic ability from cyclic voltammetry and fast electron transfer rate according to the electron transfer resistance of 330Ω from impedance spectroscopy. Differential pulse voltammetry results showed the sensitivity to glucose was 3.99µA∗cm-2∗mM-1, the linearity increased to 180mM and the detection limit was 22.6µM. The prepared nonenzyme glucose sensor with good analytical performance and simple preparation method looks promising in accurate glucose detection applications.


Asunto(s)
Nanopartículas del Metal , Técnicas Electroquímicas , Glucosa , Nanotubos , Platino (Metal) , Plata , Titanio
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