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1.
Adv Mater ; 36(33): e2405024, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38736201

RESUMO

Organic multiferroic heterostructure is one of the most promising structures for the future design of high-density flexible energy-efficient data storage. Here, organic ferromagnetic metal(tetracyanoethylene) (M(TCNE))x/ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) multiferroic heterostructures are fabricated, where the excited state in M(TCNE)x interacted with localized dipole in P(VDF-TrFE) provides a key link for the interfacial coupling. Thus, aligned dipoles in P(VDF-TrFE) by external electric field can affect the magnetization of Fe(TCNE)x effectively to result in a pronounced magnetization-voltage (M-V) hysteresis loop. Moreover, light-induced electron-hole pairs in Fe(TCNE)x with long lifetime effectively interact with the dipoles in P(VDF-TrFE) to lead to an effect in external light control of electric polarization of P(VDF-TrFE). Overall, the organic multiferroic heterostructure provides the possibility of realizing two storage modes, light control of dipole as well as electric field control of spin, which can broaden multifunctional applications of organic multiferroic materials in the area of multistate storage.

2.
Cancer Manag Res ; 16: 95-111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370535

RESUMO

Background: Several studies suggest that Proteasome 26S Subunit, ATPase (PSMC) family genes are of great importance in tumor progression and spreading, but the study for systematic evaluation of the function of PSMC genes in hepatocellular carcinoma (HCC) is currently lacking. Methods: The functions of PSMC genes in HCC were analyzed using multiple online databases, including the TCGA database, GEO database, HPA database, cBioPortal database, DAVID, and KEGG pathway. Experiments were later conducted to verify PSMC expression. Results: High levels of PSMC gene expression were detected in HCC tissues and PSMCs exhibited potentially powerful abilities in diagnosing HCC patients. All PSMC proteins are expressed to varying degrees in HCC tissues and high expression of the PSMC genes lead to poor prognosis in patients with HCC. Moreover, DNA methylation involves the regulation of the expression of PSMC2 and PSMC5 in HCC, and the levels of methylation of PSMC2 or PSMC5 correlate positively with patient overall survival in HCC patients. The copy number alteration and mutation of PSMC genes were observed and related to the expression of PSMCs in HCC. Functional enrichment analysis showed that many highly co-expressed genes of PSMCs had a potential role in tumor progression and metastasis, which merited further in-depth study. Functional network analysis also suggests that the primary biological function of PSMC genes is the regulation of protein homeostasis and energy metabolism in HCC. Moreover, the expression levels of PSMCs are related to immune cell infiltrates and immunomodulatory factors in HCC. Conclusion: Our study indicates that PSMC genes are the potential target for precision immunotherapy and novel prognostic biomarkers for HCC.

3.
Opt Express ; 31(12): 19622-19631, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381373

RESUMO

Transition metal dichalcogenides (TMDs) have attracted great attention in valleytronics. Owing to the giant valley coherence at room temperature, valley pseudospin of TMDs open a new degree of freedom to encode and process binary information. The valley pseudospin only exists in non-centrosymmetric TMDs (e.g., monolayer or 3R-stacked multilayer), which is prohibited in conventional centrosymmetric 2H-stacked crystals. Here, we propose a general recipe to generate valley-dependent vortex beams by using a mix-dimensional TMD metasurface composed of nanostructured 2H-stacked TMD crystals and monolayer TMDs. Such an ultrathin TMD metasurface involves a momentum-space polarization vortex around bound states in the continuum (BICs), which can simultaneously achieve strong coupling (i.e., form exciton polaritons) and valley-locked vortex emission. Moreover, we report that a full 3R-stacked TMD metasurface can also reveal the strong-coupling regime with an anti-crossing pattern and a Rabi splitting of 95 meV. The Rabi splitting can be precisely controlled by geometrically shaping the TMD metasurface. Our results provide an ultra-compact TMD platform for controlling and structuring valley exciton polariton, in which the valley information is linked with the topological charge of vortex emission, which may advance valleytronic, polaritonic, and optoelectronic applications.

4.
Sensors (Basel) ; 22(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36146083

RESUMO

In this paper, a cooperative search method for multiple UAVs is proposed to solve the problem of low efficiency of multi-UAV task execution by using a cooperative game with incomplete information. To improve search efficiency, CBBA (Consensus-Based Bundle Algorithm) is applied to designate the tasks area for each UAV. Then, Independent Deep Reinforcement Learning (IDRL) is used to solve Nash equilibrium to improve UAVs' collaborations. The proposed reward function is smartly developed to guide UAVs to fly along the path with higher reward value while avoiding the collisions between UAVs during flights. Finally, extensive experiments are carried out to compare our proposed method with other algorithms. Simulation results show that the proposed method can obtain more rewards in the same period of time as other algorithms.


Assuntos
Aeronaves , Algoritmos , Simulação por Computador , Recompensa
5.
ACS Nano ; 16(3): 4843-4850, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35171574

RESUMO

Manipulating magnetic bits by photon in spintronics, opto-magnetic coupling, is lagging far behind what we could expect. To investigate the issue, one should face the problem to find photon dependence of spin dynamics and spin manipulation. In this work, through introducing chiral orbit in organic crystals, circularly polarized photon can manipulate spin via the channel of photon-orbit-spin interactions. Under the stimulus of the magnetic field, strong spin polarization will feed back to the change in polarized state of light. Moreover, twisting several chiral nanofibers into a thick one, a more pronounced opto-magnetic coupling is clearly observed due to the chirality generated larger chiral orbit. Meanwhile, spin dynamics (or spin response times) inside the aggregated thick chiral fiber can be further tuned by circularly polarized light. Hopefully, this study can deepen the understanding of organic chiral spin-photonics and enhance the application of organic functional crystals in the future.

6.
Opt Express ; 28(20): 28916-28923, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114800

RESUMO

Based on the angular spectrum of high order off-axis Airy vortex beams (AiVBs), Goos-Hänchen (GH) shifts and Imbert-Fedorov (IF) shifts near the Brewster angle are numerically calculated. It is found that both GH and IF shifts increase with the increase of the vortex's topological charge of AiVBs. The influences of the vortex's positions on GH and IF shifts are studied for the case of the topological charge m = 1. The studies of the off-axis vortex show that the influences of the vortex's position on shifts are inversely proportional to the distance between the vortex's position and the origin point.

7.
Scand J Gastroenterol ; 55(6): 640-645, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32493095

RESUMO

Objectives: Although Helicobacter pylori (H. pylori) infection is one of the most important risk factors for gastric cancer, the molecular mechanisms underlying the progression of H. pylori-induced gastric cancer remain unclear. Previous studies have demonstrated that Integrin-associated protein (CD47) plays an important role in the development of gastric cancer. Hence, the aim of this study was to preliminarily explore the relationship between CD47 and H. pylori infection.Methods: A total of 417 adults who underwent health checkups at a hospital were recruited in 2018. Serum levels of CD47 and tumor necrosis factor-α (TNF-α) were determined using an enzyme-linked immunosorbent assay. 13C urea breath test (13C-UBT) was carried out to diagnose H. pylori infection in all participants.Results: Compared with H. pylori-negative participants, H. pylori-positive participants have higher levels of serum CD47 and TNF-α. H. pylori infection, the levels of serum TNF-α and low density lipoprotein (LDL) are the independent predictors of serum level of CD47 in adults. In addition, a potential diagnostic value of serum CD47 level for H. pylori infection has been demonstrated in our study.Conclusion: H. pylori infection is closely associated with the serum level of CD47 in adults, suggesting that H. pylori may promote gastric cancer progression by activating CD47-mediated oncogenic pathways.


Assuntos
Antígeno CD47/sangue , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto , Idoso , Testes Respiratórios , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Neoplasias Gástricas/etiologia , Ureia
8.
Opt Express ; 28(7): 10531-10541, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225636

RESUMO

Expressions of Goos-Hänchen and Imbert-Fedorov shifts of rotational 2-D finite energy Airy beams are introduced in this paper. The influences of the second-order terms of the reflection coefficient on the spatial Goos-Hänchen shift (GHS) and spatial Imbert-Fedorov shift (IFS) of rotational 2-D finite energy Airy beams are theoretically and numerically investigated at the surface between air and weakly absorbing medium for the first time. It is found that the axial symmetry of the initial field of beams has huge influences on GHS and IFS and both of the GHS and IFS can be controlled by adjusting the rotation angle of the initial field distribution.

9.
Nano Lett ; 19(12): 9008-9012, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31692362

RESUMO

Organic chiral materials have brought attention due to their potential application in the area of spin-optics and optoelectronics. Compared with traditional achiral materials, the chirality generated orbital angular momentum (CGO) is one of the key properties for chiral materials. Here, organic nanocrystals with chirality are fabricated to study the effect of the CGO on the magneto-optic coupling. The CGO affects spin states through spin-orbital coupling, which will suppress spin relaxation time to tens of picoseconds. Furthermore, spin states in chiral crystals will be further tuned by the external magnetic field to demonstrate the dependence of spin-photon coupling effects on the magnetic field.

10.
Adv Mater ; 31(48): e1904857, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31588656

RESUMO

Circularly polarized light emission promotes the development of smart photonic materials for advanced applications in chiral sensing and information storage. The orbital angular momentum is a unique property for organic chiral helical materials. In this work, a type of organic chiral polymeric nanowires is designed with strong chirality induced orbital angular momentum. Under the stimulus of an external magnetic field of 600 mT, circularly polarized emission from the chiral polymeric nanowire becomes more pronounced, where the g factor increases from 0.21 to 0.3. The observed phenomena mainly originate from the chirality-dependent orbital angular momentum. Moreover, the orbital angular momentum in helical chiral nanowire structures can be suppressed by inhibiting electron transport in a helical way to diminish circularly polarized light emission at room temperature.

11.
ACS Nano ; 13(4): 4705-4711, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30869866

RESUMO

In this work, through designing organic helix donor-acceptor complexes, one type of room-temperature chiral magnet was reported. Within these chiral charge transfer magnets, circularly polarized light could induce a larger saturation magnetization compared to linearly polarized light illumination with identical intensity. Moreover, the transmission light polarization from chiral magnets could be tuned via applying the magnetic field. Overall, room-temperature organic chiral magnets with optomagnetic effects will enhance the function of organic magnetochiral materials.

12.
Sensors (Basel) ; 19(4)2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30781406

RESUMO

Due to the ever-increasing number and diversity of data sources, and the continuous flow of data that are inevitably redundant and unused to the cloud, the Internet of Things (IoT) brings several problems including network bandwidth, the consumption of network energy, cloud storage, especially for paid volume, and I/O throughput as well as handling huge amount of stored data in the cloud. These call for data pre-processing at the network edge before data transmission over the network takes place. Data reduction is a method for mitigating such problems. Most state-of-the-art data reduction approaches employ a single tier, such as gateways, or two tiers, such gateways and the cloud data center or sensor nodes and base station. In this paper, an approach for IoT data reduction is proposed using in-networking data filtering and fusion. The proposed approach consists of two layers that can be adapted at either a single tier or two tiers. The first layer of the proposed approach is the data filtering layer that is based on two techniques, namely data change detection and the deviation of real observations from their estimated values. The second layer is the data fusion layer. It is based on a minimum square error criterion and fuses the data of the same time domain for specific sensors deployed in a specific area. The proposed approach was implemented using Python and the evaluation of the approach was conducted based on a real-world dataset. The obtained results demonstrate that the proposed approach is efficient in terms of data reduction in comparison with Least Mean Squares filter and Papageorgiou's (CLONE) method.

13.
Sensors (Basel) ; 12(4): 4715-29, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22666054

RESUMO

Transmission range plays an important role in the deployment of a practical underwater acoustic sensor network (UWSN), where sensor nodes equipping with only basic functions are deployed at random locations with no particular geometrical arrangements. The selection of the transmission range directly influences the energy efficiency and the network connectivity of such a random network. In this paper, we seek analytical modeling to investigate the tradeoff between the energy efficiency and the network connectivity through the selection of the transmission range. Our formulation offers a design guideline for energy-efficient packet transmission operation given a certain network connectivity requirement.

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