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1.
Opt Express ; 28(5): 6408-6416, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225889

RESUMO

In this paper, a method to measure the tiny spin splitting of the spin Hall effect of light (SHEL) using the almost-balanced weak measurement (ABWM) is presented. The ABWM technique uses two orthogonal post-selected states to record all of the information, which is a precise measurement method being different from the standard weak measurement (SWM). The theory model to describe the SHEL measurement based on ABWM is established. As results, the ABWM scheme has a larger amplification factor, reaching ∼105, which is nearly one order of magnitude higher than that of the SWM. When the post-selected angle is less than a certain value, the sensitivity and amplification factor of the ABWM scheme are higher than those of the SWM scheme, while the measurement precision and SNR of the ABWM technique are comparable to those of the SWM scheme. This research may have great potential for the precision metrology or sensing field based on the SHEL measurement.

2.
Opt Lett ; 45(5): 1075-1078, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108773

RESUMO

In this Letter, we propose a technique for hysteresis loop measurement based on weak measurement. By using the photonic spin Hall effect (PSHE) as a probe and combining the quantum weak measurement, the technique's noise can be suppressed greatly. A theoretical model to describe the numerical relation between the amplified shift and Kerr rotation angle is established. Through detecting the amplified shift of the PSHE based on weak measurement, we experimentally measure the hysteresis loops of Ni-Fe alloy film, iron-phthalocyanine (FePc) monolayer film, and Co/FePc double-layer film. The results show that the precision can reach about $ \sim {10^{ - 6}} \;{\rm rad} $∼10-6rad under ordinary experimental conditions, which may have an important application prospect in magneto-optic parameters measurement.

3.
Opt Express ; 26(18): 22934-22943, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184950

RESUMO

The Imbert-Fedorov (IF) shift is defined as the transverse shift of barycenter of the entire beam when a circular or elliptically polarized incident beam is reflected. In this work, we examine the IF shift of Gaussian beam at the Brewster angle. Interestingly, the spin Hall effect of light takes place in the IF shift at the same time. Furthermore, this interesting phenomenon is experimentally observed using weak measurements. These findings may have useful applications in spin optics.

4.
Opt Express ; 25(18): 21107-21114, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29041518

RESUMO

In this paper, a method to improve the precision of prism-coupler-based surface plasmon resonance (SPR) sensors using weak-value amplification (WVA) is presented. A general theory model to describe the post-selected SPR sensing system is established and the polarization-dependent amplitude and phase evolutions induced by the SPR are regarded as the weak interactions in the WVA formalism. As a consequence of WVA, the detected signal can be enhanced with respect to the technical noise which is dependent on the post-selected light intensity. The precision of our method reaches 2.9 × 10-7RIU, which is improved nearly one order of magnitude compared to the conventional sensing technique.

5.
Brain Res ; 1844: 149169, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39179194

RESUMO

OBJECTIVE: Depression and insomnia frequently co-occur, but the neural mechanisms between patients with varying degrees of these conditions are not fully understood. The specific topological features and connectivity patterns of this co-morbidity have not been extensively studied. This study aimed to investigate the topological characteristics of topological characteristics and functional connectivity of brain networks in depressed patients with insomnia. METHODS: Resting-state functional magnetic resonance imaging data from 32 depressed patients with a high level of insomnia (D-HI), 35 depressed patients with a low level of insomnia (D-LI), and 81 healthy controls (HC) were used to investigate alterations in brain topological organization functional networks. Nodal and global properties were analyzed using graph-theoretic techniques, and network-based statistical analysis was employed to identify changes in brain network functional connectivity. RESULTS: Compared to the HC group, both the D-HI and D-LI groups showed an increase in the global efficiency (Eglob) values, local efficiency (Eloc) was decreased in the D-HI group, and Lambda and shortest path length (Lp) values were decreased in the D-LI group. At the nodal level, the right parietal nodal clustering coefficient (NCp) values were reduced in D-HI and D-LI groups compared to those in HC. The functional connectivity of brain networks in patients with D-HI mainly involves default mode network (DMN)-cingulo-opercular network (CON), DMN-visual network (VN), DMN-sensorimotor network (SMN), and DMN-cerebellar network (CN), while that in patients with D-LI mainly involves SMN-CON, SMN-SMN, SMN-VN, and SMN-CN. The values of the connection between the midinsula and postoccipital gyrus was negatively correlated with scores for early awakening in D-HI. CONCLUSION: These findings may contribute to our understanding of the underlying neuropsychological mechanisms in depressed patients with insomnia.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Rede Nervosa , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Adulto , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Pessoa de Meia-Idade , Depressão/fisiopatologia , Depressão/diagnóstico por imagem , Mapeamento Encefálico/métodos , Vias Neurais/fisiopatologia , Descanso/fisiologia
6.
Front Immunol ; 14: 1118933, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845118

RESUMO

Enterovirus D68 (EV-D68) is a globally re-emerging respiratory pathogen implicated in outbreaks of severe respiratory illnesses and associated with acute flaccid myelitis. However, effective vaccines or treatments for EV-D68 infections remain scarce. We demonstrated that the active constituent of blueberries, pterostilbene (Pte), and its major metabolite, pinostilbene (Pin), facilitated innate immune responses in EV-D68-infected human respiratory cells. Pte and Pin treatment clearly relieved EV-D68-triggered cytopathic effects. Importantly, both Pte and Pin disrupted viral RNA replication (EC50 rank from 1.336 to 4.997 µM) and infectious virion production in a dose-dependent manner, without cytotoxicity at virucidal concentrations. Pte- or Pin-treated respiratory cells did not show any influences on EV-D68 entry but showed substantially decreased viral RNA replication and protein synthesis. Finally, we showed that Pte and Pin broadly suppressed the replication capacity of circulating EV-D68 strains isolated from recent pandemics. In summary, our results suggest that Pte and its derivative, Pin, enhance host immune recognition of EV-D68 and suppress EV-D68 replication, which represents a promising strategy for antiviral drug development.


Assuntos
Mirtilos Azuis (Planta) , Enterovirus Humano D , Infecções por Enterovirus , Humanos , Infecções por Enterovirus/tratamento farmacológico , Imunidade Inata
7.
Artigo em Inglês | MEDLINE | ID: mdl-32104190

RESUMO

OBJECTIVE: In traditional Chinese medicine (TCM), chronic myeloid leukemia (CML) has been attributed to "poisoned bone marrow," which is viewed as a loss of Qi or blood, a deficiency in Yin or Yang that causes a complex imbalance between cell growth and death. Malignant myeloid progenitor cells display excessive growth that is difficult to control without toxicity. More than 60 herbs in TCM have shown efficacy against CML. However, the key molecules and mechanisms involved in the holistic-level characterization, as well as the effective target associations, are still unknown. METHODS: The present study employed a computational approach with filtering potential compounds via admetSAR, systems biology-based functional data prediction, and biochemical and molecular biological validation. RESULTS: We generated 118 bioactive compounds from 11 herbs within four dialectical therapy groups that are most commonly used to treat CML and predicted 141 potential targets. The stilbene resveratrol and its derivatives were found to be highly related to these targets. Among them, α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. In vitro, experimental data showed a nonnecrotic growth limitation of K562 cells caused by α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. µg·mL-1 at 24 h. Finally, we validated the chemotherapeutic effect of α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies. CONCLUSIONS: Our work sheds light on the mechanism of the efficacy of the stilbene α-viniferin in TCM for the prevention of CML. This work also predicts and validates targets in the mitochondrial signaling pathway, providing a novel strategy for CML treatment.α-viniferin was predicted to target Bcl-2, caspase-3, 8, and 9, MAPK14, CDK2, HSP90AA1, and others, reflecting CML therapeutic strategies.

8.
Int J Environ Res Public Health ; 11(10): 10537-58, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25321873

RESUMO

As the land ecosystem provides the necessary basic material resources for human development, land ecological security (LES) plays an increasingly important role in sustainable development. Given the degradation of land ecological security under rapid urbanization and the urgent LES requirements of urban populations, a comprehensive evaluation method, named Double Land Ecological Security (DLES), has been introduced with the city of Guangzhou, China, as a case study, which evaluates the LES in regional and unit scales for reasonable and specific urban planning. In the evaluation process with this method, we have combined the material security with the spiritual security that is inevitably associated with LES. Some new coefficients of land-security supply/demand distribution and technology contribution for LES evaluation have also been introduced for different spatial scales, including the regional and the unit scales. The results for Guangzhou indicated that, temporally, the LES supply indices were 0.77, 0.84 and 0.77 in 2000, 2006 and 2009 respectively, while LES demand indices for the city increased in 2000, 2006 and 2009 from 0.57 to 0.95, which made the LES level decreased slowly in this period. Spatially, at the regional scale, the urban land ecological security (ULES) level decreased from 0.2 (marginal security) to -0.18 (marginal insecurity) as a whole; in unit scale, areas in the north and in parts of the east were relatively secure and the security area was shrinking with time, but the central and southern areas turned to be marginal insecurity, especially in 2006 and 2009. This study proposes that DLES evaluation should be conducted for targeted and efficient urban planning and management, which can reflect the LES level of study area in general and in detail.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Urbanização , Agricultura/estatística & dados numéricos , China , Cidades , Planejamento de Cidades/estatística & dados numéricos , Ecologia/métodos , Humanos
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