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1.
Phys Rev Lett ; 132(20): 206902, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829101

RESUMO

Developing quantum networks necessitates coherently connecting distant systems via remote strong coupling. Here, we demonstrate long-distance coherence in cavity magnonics operating in the linear regime. By locally setting the cavity near critical coupling with traveling photons, nonlocal magnon-photon coherence is established via strong coupling over a 2-m distance. We observe two anomalies in this long-distance coherence: first, the coupling strength oscillates twice the period of conventional photon-mediated couplings; second, clear mode splitting is observed within the cavity linewidth. Both effects cannot be explained by conventional coupled-mode theory, which reveals the tip of an iceberg of photon-mediated coupling in systems under critical driving. Our Letter shows the potential of using critical phenomena for harnessing long-distance coherence in distributed systems.

2.
Phys Rev Lett ; 130(14): 146702, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084460

RESUMO

By developing a gain-embedded cavity magnonics platform, we create a gain-driven polariton (GDP) that is activated by an amplified electromagnetic field. Distinct effects of gain-driven light-matter interaction, such as polariton auto-oscillations, polariton phase singularity, self-selection of a polariton bright mode, and gain-induced magnon-photon synchronization, are theoretically studied and experimentally manifested. Utilizing the gain-sustained photon coherence of the GDP, we demonstrate polariton-based coherent microwave amplification (∼40 dB) and achieve high-quality coherent microwave emission (Q>10^{9}).

3.
Phys Rev Lett ; 125(14): 147202, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064512

RESUMO

By engineering an anti-parity-time (anti-PT) symmetric cavity magnonics system with precise eigenspace controllability, we observe two different singularities in the same system. One type of singularity, the exceptional point (EP), is produced by tuning the magnon damping. Between two EPs, the maximal coherent superposition of photon and magnon states is robustly sustained by the preserved anti-PT symmetry. The other type of singularity, arising from the dissipative coupling of two antiresonances, is an unconventional bound state in the continuum (BIC). At the settings of BICs, the coupled system exhibits infinite discontinuities in the group delay. We find that both singularities coexist at the equator of the Bloch sphere, which reveals a unique hybrid state that simultaneously exhibits the maximal coherent superposition and slow light capability.

4.
Phys Rev Lett ; 123(12): 127202, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31633946

RESUMO

We reveal the cooperative effect of coherent and dissipative magnon-photon couplings in an open cavity magnonic system, which leads to nonreciprocity with a considerably large isolation ratio and flexible controllability. Furthermore, we discover unidirectional invisibility for microwave propagation, which appears at the zero-damping condition for hybrid magnon-photon modes. A simple model is developed to capture the generic physics of the interference between coherent and dissipative couplings, which accurately reproduces the observations over a broad range of parameters. This general scheme could inspire methods to achieve nonreciprocity in other systems.

5.
Zhonghua Jie He He Hu Xi Za Zhi ; 42(10): 760-764, 2019 Oct 12.
Artigo em Zh | MEDLINE | ID: mdl-31594110

RESUMO

Objective: To explore the difference of mRNA, protein expression levels and the indexes of peripheral blood antioxidant capacity in peripheral blood lymphocytes of different EPHX1 genotypes in chronic obstructive pulmonary disease(COPD). Methods: A case-control study was conducted to collect peripheral blood samples of 220 stable chronic COPD patients with smoking history and 230 healthy smokers (control group) from October 2016 to February 2018 in the First Affiliated Hospital of Kunming Medical University, and the genetic testing was carried out according to the operation instructions of BigDye Terminator v1.1 DNA Sequencing Kit. Based on their EPHX1 exon 3 and exon 4 polymorphism status, the EPHX1 was classified into 4 groups, i. e., normal activity, slow activity, extremely slow activity and fast activity. Then COPD patients were allocated to either a slow activity group (slow and very slow activity) or a fast activity group (normal and fast activity) according to EPHX1 genotype and gene activity. The expression of EPHX1 mRNA and protein in peripheral blood lymphocytes were detected by qRT-PCR and Western blot, and indexes of serum antioxidant capacity was detected by corresponding kits. Results: (1)The 2(-ΔΔCt) of the control group was 1.000, and the 2(-ΔΔCt) of the COPD group was 1.052±0.023. There was no significant difference in the level of EPHX1 mRNA expression between the two groups (t=1.992 P=0.865). The level of EPHX1 mRNA expression in the slow activity group was not different significantly compared to that in the fast-active group (1.053±0.023 vs 1.048±0.021, t=1.133, P=0.260). (2)The level of EPHX1 protein expression by Western blot analysis showed that the EHPX1/GAPDH gray ratio was not different significantly between the COPD group and the control group (0.613±0.089 vs 0.602±0.075, t=0.805, P=0.422). The level of EPHX1 protein expression in the slow activity group was not significantly different compared to that in the fast activity group (0.606±0.088 vs 0.622±0.092, t=-0.786 P=0.434). (3)There were significant differences in indexes of antioxidant capacity between the control group and the COPD group (P<0.05). There were significant differences in indexes of antioxidant capacity between the slow activity group and the fast activity group of COPD patients (P<0.05). Conclusions: The different antioxidant capacity of COPD patients with different EPHX1 genotypes may be related to the polymorphism of EPHX1 gene affecting the activity of microsomal epoxidase, but not to the level of EPHX1 mRNA and protein expression.


Assuntos
Antioxidantes/metabolismo , Povo Asiático/genética , Epóxido Hidrolases/genética , Doença Pulmonar Obstrutiva Crônica/genética , Fumar/efeitos adversos , Adulto , Western Blotting , Estudos de Casos e Controles , China/epidemiologia , Epóxido Hidrolases/metabolismo , Predisposição Genética para Doença/genética , Genótipo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Humanos , Pessoa de Meia-Idade , Polimorfismo Genético , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Fumar/epidemiologia
6.
Fa Yi Xue Za Zhi ; 35(4): 433-436, 2019 Aug.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-31532152

RESUMO

ABSTRACT: Objective To investigate the characteristics and patterns of factors such as victims' information, injury tools and time of occurrence of intentional injury cases in southwest China. Methods One thousand three hundred and forty intentional injury cases from several places in southwest China from 2014 to 2016 assessed as minor injury level Ⅱ and above had been randomly selected. Data on victims' information, motives, injury tools, sites of occurrence, time of occurrence, injured parts and degrees of injury were classified and gathered, and then association analyses of motives and types of injury tools as well as degrees of injury and injury tools were made. Results Most of the victims were young adults between 20-50 years (65.2%), male (82.3%), rural household registration (62.8%); the motives were mainly dispute (45.8%). Injury tools were mostly blunt (54.6%) or sharp (36.0%). Specifically, injuries were mostly made bare-handed (36.9%) and by cutting tools (33.2%); the cases mainly occurred in public areas (59.0%). Cases occurred more frequently in January (11.3%), February (13.1%), March (11.6%) and from 22:00 to 01:00 every night. Injuries mainly involved the craniofacial region. The wounds were mainly assessed as minor injury level Ⅱ (61.6%). There was statistical significance in the difference of types of injury tools among cases with different motives (P<0.05). There was statistical significance in the difference of the distribution of injury tools among cases with different degrees of injury (P<0.05). Conclusion The occurrence of intentional injury cases in southwest China has potential patterns and relevant influencing factors. Prevention and analysis of such cases need to be comprehensively considered from the aspects such as victims' information, injury tools and time of occurrence.


Assuntos
Motivação , Violência , Ferimentos e Lesões/etiologia , Adulto , Distribuição por Idade , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Ferimentos e Lesões/diagnóstico , Adulto Jovem
7.
Phys Rev Lett ; 120(5): 057202, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29481165

RESUMO

We report the first observation of the magnon-polariton bistability in a cavity magnonics system consisting of cavity photons strongly interacting with the magnons in a small yttrium iron garnet (YIG) sphere. The bistable behaviors emerged as sharp frequency switchings of the cavity magnon polaritons (CMPs) and related to the transition between states with large and small numbers of polaritons. In our experiment, we align, respectively, the [100] and [110] crystallographic axes of the YIG sphere parallel to the static magnetic field and find very different bistable behaviors (e.g., clockwise and counter-clockwise hysteresis loops) in these two cases. The experimental results are well fitted and explained as being due to the Kerr nonlinearity with either a positive or negative coefficient. Moreover, when the magnetic field is tuned away from the anticrossing point of CMPs, we observe simultaneous bistability of both magnons and cavity photons by applying a drive field on the lower branch.

8.
Phys Rev Lett ; 121(13): 137203, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30312103

RESUMO

We report dissipative magnon-photon coupling caused by the cavity Lenz effect, where the magnons in a magnet induce a rf current in the cavity, leading to a cavity backaction that impedes the magnetization dynamics. This effect is revealed in our experiment as level attraction with a coalescence of hybridized magnon-photon modes, which is distinctly different from level repulsion with mode anticrossing caused by coherent magnon-photon coupling. We develop a method to control the interpolation of coherent and dissipative magnon-photon coupling, and observe a matching condition where the two effects cancel. Our work sheds light on the so-far hidden side of magnon-photon coupling, opening a new avenue for controlling and utilizing light-matter interactions.

9.
Nanotechnology ; 29(25): 254002, 2018 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-29596061

RESUMO

Motivated by recent studies of cavity magnon polariton (CMP), we extended a previous theoretical work to generalize microwave transmission calculation with various magnetization boundary condition of YIG thin film embedded in cavity. It is found that numerical implementation given in this paper can be easily applied to other magnetization boundary condition and extended to magnetic multilayers. Numerical results show that ferromagnetic resonance mode of microwave transmission spectrum, which is absent in previous calculation, can be recovered by altering the pinning condition of surface spins. The demonstrated reliability of our theory opens attractive perspectives for studying CMP of thin film with complicated surface magnetization distribution and magnetic multilayers.

10.
J Biol Regul Homeost Agents ; 32(3): 589-597, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29921385

RESUMO

Pure red cell aplasia (PRCA) develops as a result of erythroid precursors failing to reach maturity in the bone marrow, which eventually leads to anemia. Here we present a case of a 64-year-old Asian male with a medical history of colorectal adenocarcinoma who had been treated with 6 cycles of oxaliplatin and capecitabine four years ago. The patient was diagnosed with PRCA and T-cell large granular lymphocyte leukemia.


Assuntos
Leucemia Linfocítica Granular Grande/diagnóstico , Aplasia Pura de Série Vermelha/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Biol Regul Homeost Agents ; 31(2): 447-451, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28685551

RESUMO

Primary frontal sinus lymphoma is a rare disease, with the presenting symptoms that are secondary to the tumor mass effect and often misleading. Here we describe the case of a 43-year-old male patient who presented with a 4-week history of a gradually enlarging painful diffuse swelling over the right frontal sinus region. We report the clinical presentation, differential diagnosis and treatment of the case. We also reviewed the available literature on the diffuse large B-cell lymphoma in the frontal sinus region. The article emphasizes the importance of early recognition of this rare disease.


Assuntos
Seio Frontal , Linfoma Difuso de Grandes Células B , Neoplasias dos Seios Paranasais , Adulto , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/terapia , Masculino , Neoplasias dos Seios Paranasais/diagnóstico , Neoplasias dos Seios Paranasais/terapia
13.
Phys Rev Lett ; 114(22): 227201, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26196640

RESUMO

We use electrical detection, in combination with microwave transmission, to investigate both resonant and nonresonant magnon-photon coupling at room temperature. Spin pumping in a dynamically coupled magnon-photon system is found to be distinctly different from previous experiments. Characteristic coupling features such as modes anticrossing, linewidth evolution, peculiar line shape, and resonance broadening are systematically measured and consistently analyzed by a theoretical model set on the foundation of classical electrodynamic coupling. Our experimental and theoretical approach paves the way for pursuing microwave coherent manipulation of pure spin current via the combination of spin pumping and magnon-photon coupling.

14.
Genet Mol Res ; 13(2): 2628-37, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24782051

RESUMO

This study aimed to explore the interaction and crosstalk between pathways in response to destrin mutations. All the pathways from the MINT database were downloaded, a protein-protein interaction network was then constructed, and the crosstalk between pathways was investigated, in particular, the overlap of 2 significant pathway analysis results. As expected, the results showed that regulation of the actin cytoskeleton was the significant pathway of destrin mutations in mice. Further analysis indicated that 28 significant pathways cross-talked with the pathway regulating the actin cytoskeleton. Importantly, 3 pathways, including regulation of actin cytoskeleton pathway, pathways in cancer, and the B cell receptor signaling pathway were linked by inositol phosphate metabolism based on crosstalk analysis of Gene Ontology relationships among pathways. All of these pathways have been demonstrated to participate in cytoskeleton dynamics. These findings might provide valuable insights into cytoskeleton dynamic abnormalities in destrin mutations of corneal diseases.


Assuntos
Destrina/genética , Transdução de Sinais/genética , Citoesqueleto de Actina/genética , Animais , Doenças da Córnea/etiologia , Doenças da Córnea/genética , Destrina/biossíntese , Camundongos , Análise em Microsséries , Proteínas dos Microfilamentos/genética , Mutação , Transcriptoma
15.
Phys Rev Lett ; 111(21): 217602, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313526

RESUMO

We develop a method for universally resolving the important issue of separating spin pumping from spin rectification signals in bilayer spintronics devices. This method is based on the characteristic distinction of spin pumping and spin rectification, as revealed in their different angular and field symmetries. It applies generally for analyzing charge voltages in bilayers induced by the ferromagnetic resonance (FMR), independent of FMR line shape. Hence, it solves the outstanding problem that device-specific microwave properties restrict the universal quantification of the spin Hall angle in bilayer devices via FMR experiments. Furthermore, it paves the way for directly measuring the nonlinear evolution of spin current generated by spin pumping. The spin Hall angle in a Py/Pt bilayer is thereby directly measured as 0.021±0.015 up to a large precession cone angle of about 20°.

16.
Nat Commun ; 14(1): 3437, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301861

RESUMO

Recent works in metamaterials and transformation optics have demonstrated exotic properties in a number of open systems, including perfect absorption/transmission, electromagnetically induced transparency, cloaking or invisibility, etc. Meanwhile, non-Hermitian physics framework has been developed to describe the properties of open systems, however, most works related to this focus on the eigenstate properties with less attention paid to the reflection characteristics in complex frequency plane, despite the usefulness of zero-reflection (ZR) for applications. Here we demonstrate that the indirectly coupled two-magnon system not only exhibits non-Hermitian eigenmode hybridization, but also ZR states in complex frequency plane. The observed perfect-ZR (PZR) state, i.e., ZR with pure real frequency, is manifested as infinitely narrow reflection dips (~67 dB) with infinite group delay discontinuity. This reflection singularity of PZR distinguishes from the resonant eigenstates but can be adjusted on or off resonance with the eigenstates. Accordingly, the absorption and transmission can be flexibly tuned from nearly full absorption (NFA) to nearly full transmission (NFT) regions.


Assuntos
Hibridização Genética , Física , Vibração
17.
Zhonghua Er Ke Za Zhi ; 61(5): 440-445, 2023 May 02.
Artigo em Zh | MEDLINE | ID: mdl-37096264

RESUMO

Objective: To explore the risk factors of malnutrition in infants with congenital heart disease within one year after surgery. Methods: This retrospective cohort study selected 502 infants with congenital heart disease who underwent surgical treatment in Guangzhou Women and Children's Medical Center from February 2018 to January 2019. Their basic information and clinical data were analyzed, and their nutrition status after the surgery was followed up by questionnaire survey. Weight-for-age Z score (WAZ)≤-2 one year after operation was defined as malnutrition group, and WAZ>-2 was non-malnutrition group. The perioperative indicators and complementary food advancement were compared between the two groups by chi-square test, t-test, and Kruskal-Wallis test. The risk factors of malnutrition were analyzed by Logistic regression. Results: A total of 502 infants were selected, including 301 males and 201 females, with the age of 4.1 (2.0, 6.8) months. There were 90 cases in malnutrition group and 412 cases in non-malnutrition group. The body length and weight at birth in the malnutrition group were lower than those in the non-malnutrition group ((47.8±3.8) vs. (49.3±2.5) cm, (2.7±0.6) vs.(3.0±0.5) kg, both P<0.001). The proportion of paternal high school education or above and the proportion of family per capita income of 5 000 yuan or above in the malnutrition group were lower than those in the non-malnutrition group ((18.9% (17/90) vs. 30.8% (127/412), 18.9% (17/90) vs. 33.7% (139/412), both P<0.05). Compared to the non-malnutrition group, the proportion of complex congenital heart disease in the malnutrition group was higher (62.2% (56/90) vs. 47.3% (195/412), P<0.05). The postoperative mechanical ventilation time, postoperative intensive care unit (ICU) stay time, postoperative hospital stay, total length of ICU stay and total hospital stay in the malnutrition group were significantly longer than those in non-malnutrition group (all P<0.05). The proportion of egg and fish supplementation over 2 times/week within one year after the surgery was also lower in the malnutrition group (both P<0.05). Logistic regression analysis showed that mother's weight at delivery (OR=0.95,95%CI 0.91-0.99), the pre-operative WAZ≤-2 (OR=6.04, 95%CI 3.13-11.65), the complexity of the cardiac disease (OR=2.23, 95%CI 1.22-4.06), the hospital stay after the surgery over 14 days (OR=2.61, 95%CI 1.30-5.26), the types of complementary food<4 (OR=2.57, 95%CI 1.39-4.76), and the frequency of meat and fish<2 times/week (OR=2.11, 95%CI 1.13-3.93) were the risk factors associated with malnutrition within one year after the surgery. Conclusion: Mother's weight at delivery pre-operative nutritional status, complexity of cardiac disease, postoperative hospital stay, types of daily supplements and frequency of fish are risk factors associated with malnutrition within one year after surgery in children with congenital heart disease.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Transtornos da Nutrição do Lactente , Desnutrição , Masculino , Humanos , Feminino , Estudos Retrospectivos , Desnutrição/complicações , Cardiopatias Congênitas/cirurgia , Fatores de Risco , Tempo de Internação , Transtornos da Nutrição do Lactente/complicações
18.
Phys Rev Lett ; 109(3): 037206, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22861893

RESUMO

An intrinsic thermoelectric coupling effect in the linear response regime of magnetic tunneling junctions (MTJ) is reported. In the dc response, it leads to a nonlinear correction to Ohm's law. Dynamically, it enables a novel Seebeck rectification and second harmonic generation, which apply for a broad frequency range and can be magnetically controlled. A phenomenological model on the footing of the Onsager reciprocal relation and the principle of energy conservation explains very well the experimental results obtained from both dc and frequency-dependent transport measurements performed up to GHz frequencies. Our work refines previous understanding of magnetotransport and microwave rectification in MTJs. It forms a new foundation for utilizing spin caloritronics in high-frequency applications.

19.
Nat Commun ; 12(1): 1933, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772003

RESUMO

The perfect absorption of electromagnetic waves has promoted many applications, including photovoltaics, radar cloaking, and molecular detection. Unlike conventional methods of critical coupling that require asymmetric boundaries or coherent perfect absorption that require multiple coherent incident beams, here we demonstrate single-beam perfect absorption in an on-chip cavity magnonic device without breaking its boundary symmetry. By exploiting magnon-mediated interference between two internal channels, both reflection and transmission of our device can be suppressed to zero, resulting in magnon-induced nearly perfect absorption (MIPA). Such interference can be tuned by the strength and direction of an external magnetic field, thus showing versatile controllability. Furthermore, the same multi-channel interference responsible for MIPA also produces level attraction (LA)-like hybridization between a cavity magnon polariton mode and a cavity photon mode, demonstrating that LA-like hybridization can be surprisingly realized in a coherently coupled system.

20.
Phys Rev Lett ; 105(1): 017202, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20867473

RESUMO

A spintronic approach is introduced to transform classic Michelson interferometry that probes the electromagnetic phase only. This method utilizes a nonlinear four-wave coherent mixing effect. A previously unknown striking relation between spin dynamics and the relative phase of electromagnetic waves is revealed. Spintronic Michelson interferometry allows direct probing of both the spin-resonance phase and the relative phase of electromagnetic waves via microspintronics. Thereby, it breaks new ground for cross-disciplinary applications with unprecedented capabilities, which we demonstrate via a powerful phase-resolved spin-resonance spectroscopy on magnetic materials and an on-chip technique for phase-resolved near-field microwave imaging.

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