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1.
Nat Mater ; 22(10): 1203-1209, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37349396

RESUMO

Topological photonics is rapidly expanding. However, discovering three-dimensional topological electromagnetic systems can be more challenging than electronic systems for two reasons. First, the vectorial nature of electromagnetic waves results in complicated band dispersions, and simple tight-binding-type predictions usually fail. Second, topological electromagnetic surface modes inside the light cone have very low quality factors (Q factors). Here, we propose the concept of scalar topological photonics to address these challenges. Our approach is experimentally validated by employing a nested meta-crystal configuration using connected coaxial waveguides. They exhibit scalar-wave-like band dispersions, making the search for photonic topological phases an easier task. Their surface states have skyrmion-like electric field distributions, resulting in a whole, bright surface state band inside the light cone continuum. As such, the topological surface states in our three-dimensional nested crystals can be exposed to air, making such systems well-suited for practical applications.

2.
Opt Express ; 32(11): 19279-19293, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859066

RESUMO

Unidirectional scattering, crucial for manipulating light at the nanoscale, has wide-ranging applications from optical manipulation to sensing. While traditionally achieved through interactions between electric multipoles or between electric and magnetic multipoles, reports on unidirectional scattering driven purely by magnetic multipoles are limited. In this study, we undertake a theoretical exploration of transverse unidirectional scattering induced by magnetic multipoles, employing tightly focused azimuthally polarized beams (APBs) in interaction with a silicon nanodimer comprising two non-concentric nanorings. Through numerical simulations and theoretical analysis, we validate the transverse unidirectional scattering, predominantly governed by magnetic dipolar and quadrupolar resonances. Moreover, the directionality of this unidirectional scattering shows a strong correlation with the longitudinal displacement of the nanodimer within a specific range, showcasing its potential for longitudinal displacement sensing. Our study advances optical scattering control in nanostructures and guides the design of on-chip longitudinal displacement sensors.

3.
Opt Express ; 32(10): 17220-17228, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858911

RESUMO

It was proved that the joint operation of electromagnetic reciprocity and n-fold (n ≥ 3) rotational symmetry would secure arbitrary polarization-independent backscattering efficiency [Phys. Rev. B103(4), 045422 (2021)10.1103/PhysRevB.103.045422]. Here we remove the restriction of reciprocity and study the backscatterings of plane waves by rotationally symmetric magneto-optical structures, with collinear incident wavevector, rotational axis and externally applied magnetic field. It is revealed that though nonreciprocity removes the degeneracy of backscattering efficiencies for circularly-polarized incident waves of opposite handedness, the remaining rotational symmetry is sufficient to guarantee that the efficiency is related to the polarization ellipticity only, having nothing to do with the orientations of the polarization ellipses. Moreover, the backscattering efficiency reaches its extremes (maximum or minimum values) always for circularly-polarized incident waves, and for other polarizations the efficiency is their ellipticity-weighted arithmetic average. The principles we have revealed are dictated by rotational symmetries only, which are irrelevant to specific geometric or optical parameters and are intrinsically robust against any rotational-symmetry preserving perturbations. The correlations we have discovered could be further exploited for fundamental explorations in nonreciprocal photonics and practical applications including polarimetry and ellipsometry.

4.
Pharm Res ; 41(5): 911-920, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38509321

RESUMO

INTRODUCTION: PDX-02 (Flurbiprofen sodium) is a topical nonsteroidal anti-inflammatory drug in gel formulation for local analgesia and anti-inflammation. A Phase I clinical trial was conducted to assess the safety, tolerability, and pharmacokinetics of single and multiple doses of PDX-02 gel in Chinese healthy adults. METHODS: The trial comprised three parts: (1) a single-dose ascending study with three dose levels (0.5%, 1% to 2% PDX-02 gel) applied on a 136 cm2 skin area; (2) a multiple-dose study with either 1% or 2% PDX-02 gel applied on a 136 cm2 skin area for 7 consecutive days; and (3) a high dose group with 2% PDX-02 gel on an 816 cm2 skin area and a frequent multiple dose group with 2% PDX-02 gel on a 272 cm2 skin area four times a day for 7 consecutive days. The safety, tolerability and pharmacokinetics of the PDX-02 gel were evaluated in each part. RESULTS: A total of sixty participants completed the trial, with all adverse events recovered and all positive skin reaction being transient and recovered. The overall absorption of topical PDX-02 gel was slow with a mean peak time exceeding 9 h. The elimination rate remained consistent between dose groups. A less-than-dose-proportional nonlinear pharmacokinetics relationship was observed within the studied dose range, and this is likely due to the autoinduction of skin first-pass metabolism. CONCLUSION: The topical PDX-02 gel showed favorable safety and tolerability in both single and multiple dosing studies, with a less-than-dose-proportional nonlinear pharmacokinetics observed.


Assuntos
Anti-Inflamatórios não Esteroides , Flurbiprofeno , Géis , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Administração Cutânea , Administração Tópica , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/administração & dosagem , Relação Dose-Resposta a Droga , Flurbiprofeno/farmacocinética , Flurbiprofeno/administração & dosagem , Voluntários Saudáveis , Pele/metabolismo , Absorção Cutânea , População do Leste Asiático
5.
Mol Breed ; 44(7): 45, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38911334

RESUMO

The brown planthopper (Nilaparvata lugens Stål, BPH) is the most destructive pest of rice (Oryza sativa L.). Utilizing resistant rice cultivars that harbor resistance gene/s is an effective strategy for integrated pest management. Due to the co-evolution of BPH and rice, a single resistance gene may fail because of changes in the virulent BPH population. Thus, it is urgent to explore and map novel BPH resistance genes in rice germplasm. Previously, an indica landrace from India, Paedai kalibungga (PK), demonstrated high resistance to BPH in both in Wuhan and Fuzhou, China. To map BPH resistance genes from PK, a BC1F2:3 population derived from crosses of PK and a susceptible parent, Zhenshan 97 (ZS97), was developed and evaluated for BPH resistance. A novel BPH resistance locus, BPH39, was mapped on the short arm of rice chromosome 6 using next-generation sequencing-based bulked segregant analysis (BSA-seq). BPH39 was validated using flanking markers within the locus. Furthermore, near-isogenic lines carrying BPH39 (NIL-BPH39) were developed in the ZS97 background. NIL-BPH39 exhibited the physiological mechanisms of antibiosis and preference toward BPH. BPH39 was finally delimited to an interval of 84 Kb ranging from 1.07 to 1.15 Mb. Six candidate genes were identified in this region. Two of them (LOC_Os06g02930 and LOC_Os06g03030) encode proteins with a similar short consensus repeat (SCR) domain, which displayed many variations leading to amino acid substitutions and showed higher expression levels in NIL-BPH39. Thus, these two genes are considered reliable candidate genes for BPH39. Additionally, transcriptome sequencing, DEGs analysis, and gene RT-qPCR verification preliminary revealed that BPH39 may be involved in the jasmonic acid (JA) signaling pathway, thus mediating the molecular mechanism of BPH resistance. This work will facilitate map-based cloning and marker-assisted selection for the locus in breeding programs targeting BPH resistance. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01485-6.

6.
Twin Res Hum Genet ; 27(2): 69-79, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644690

RESUMO

While it is known that vitamin D deficiency is associated with adverse bone outcomes, it remains unclear whether low vitamin D status may increase the risk of a wider range of health outcomes. We had the opportunity to explore the association between common genetic variants associated with both 25 hydroxyvitamin D (25OHD) and the vitamin D binding protein (DBP, encoded by the GC gene) with a comprehensive range of health disorders and laboratory tests in a large academic medical center. We used summary statistics for 25OHD and DBP to generate polygenic scores (PGS) for 66,482 participants with primarily European ancestry and 13,285 participants with primarily African ancestry from the Vanderbilt University Medical Center Biobank (BioVU). We examined the predictive properties of PGS25OHD, and two scores related to DBP concentration with respect to 1322 health-related phenotypes and 315 laboratory-measured phenotypes from electronic health records. In those with European ancestry: (a) the PGS25OHD and PGSDBP scores, and individual SNPs rs4588 and rs7041 were associated with both 25OHD concentration and 1,25 dihydroxyvitamin D concentrations; (b) higher PGS25OHD was associated with decreased concentrations of triglycerides and cholesterol, and reduced risks of vitamin D deficiency, disorders of lipid metabolism, and diabetes. In general, the findings for the African ancestry group were consistent with findings from the European ancestry analyses. Our study confirms the utility of PGS and two key variants within the GC gene (rs4588 and rs7041) to predict the risk of vitamin D deficiency in clinical settings and highlights the shared biology between vitamin D-related genetic pathways a range of health outcomes.


Assuntos
Proteína de Ligação a Vitamina D , Vitamina D , Humanos , Proteína de Ligação a Vitamina D/genética , Vitamina D/sangue , Vitamina D/genética , Vitamina D/análogos & derivados , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , População Branca/genética , Fenótipo , Idoso , Deficiência de Vitamina D/genética , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Herança Multifatorial/genética
7.
Appl Opt ; 63(12): 3156-3161, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856460

RESUMO

Lithium niobate (LN)-based metasurfaces have demonstrated remarkable potential in integrated electro-optically adjustable metadevices with the maturation of thin film LN on insulator (LNOI) technology. Here, we proposed a type of high Q factor tunable metasurface with etchless LN, which is electrically driven in the vertical direction by using transparent conductive film. A transmission amplitude modulation of over 60 dB at a voltage of 20 V is realized through guided mode resonances created at the LN layer with a Q factor of 1320. Meanwhile, phase modulation is also realized with a reflective design by adding a gold layer at the bottom of the metasurface. With a gate voltage of 80 V, about 1.75π phase modulation is achieved while keeping reflection over 92%. Our proposed device achieves effective modulation of optical amplitude and phase in the near-infrared band, which lays a good foundation for the development of high performance LN-based active nanophotonic devices.

8.
J Am Chem Soc ; 145(2): 1216-1226, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36621988

RESUMO

We report a method to experimentally control the heterogeneous nucleation and growth of Au nanoparticles on the surface of amorphous Se (a-Se) nanospheres. When a AuIII precursor is added into a colloidal suspension of a-Se nanospheres, galvanic replacement occurs between them and the resultant Au0 atoms then heterogeneously nucleate and grow from the surface of the a-Se nanospheres. As a unique feature of this system, the Au0 atoms can only be produced on the surface of the a-Se nanospheres in the nucleation stage. Once Au nuclei are formed on the surface at the very beginning of a synthesis, they will serve as the preferential sites for further deposition of Au0 atoms, making it possible to control the number of Au nanoparticles on each nanosphere and the morphology of the final product. The dependence of the initial reduction rate on the pH can be used to obtain Se-Au hybrid nanoparticles containing one, two, three, and multiple Au nanoparticles on the surface of each a-Se nanosphere. The presence of Au patches on the hybrid nanoparticles offers an experimental handle to optimize the ligand distribution for the achievement of enhanced cellular uptake and cytotoxicity for the a-Se nanospheres.


Assuntos
Nanopartículas Metálicas , Nanosferas , Ouro , Nanopartículas Metálicas/toxicidade
9.
Small ; 19(45): e2302414, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37420333

RESUMO

Structural and compositional design of multifunctional materials is critical for electrocatalysis, but their rational modulation and effective synthesis remain a challenge. Herein, a controllable one-pot synthesis for construction of trifunctional sites and preparation of porous structures is adopted for synthesizing dispersed MoCoP sites on N, P codoped carbonized substance. This tunable synthetic strategy also endorses the exploration of the electrochemical activities of Mo (Co)-based unitary, Mo/Co-based dual and MoCo-based binary metallic sites. Eventually benefiting from the structural regulation, MoCoP-NPC shows excellent oxygen reduction abilities with a half-wave potential of 0.880 V, and outstanding oxygen evolution and hydrogen evolution performance with an overpotential of 316 mV and 91 mV, respectively. MoCoP-NPC-based Zn-air battery achieves excellent cycle stability for 300 h and a high open-circuit voltage of 1.50 V. When assembled in a water-splitting device, MoCoP-NPC reaches 10 mA cm-2 at 1.65 V. Theoretical calculations demonstrate that the Co atom in the single-phase MoCoP has a low energy barrier for oxygen evolution reaction (OER) owing to the migration of Co 3d orbital toward the Fermi level. This work shows a simplified method for controllable preparation of prominent trifunctional catalysts.

10.
Opt Express ; 31(10): 15372-15383, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157640

RESUMO

We theoretically propose a broadband transverse unidirectional scattering scheme based on the interaction between a tightly focused azimuthally polarized beam (APB) and a silicon hollow nanostructure. When the nanostructure is located at a specific position in the focal plane of the APB, the transverse scattering fields can be decomposed into contributions from transverse components of the electric dipoles, longitudinal components of magnetic dipoles and magnetic quadrupole components. In order to satisfy the transverse Kerker conditions for these multipoles within a wide infrared spectrum, we design a novel nanostructure with hollow parallelepiped shape. Through numerical simulations and theoretical calculations, this scheme exhibits efficient transverse unidirectional scattering effects in the wavelength range of 1440 nm to 1820 nm (380 nm). In addition, by adjusting the position of the nanostructure on the x-axis, efficient nanoscale displacement sensing with large measuring ranges can be achieved. After analyses, the results prove that our research may have potential applications in the field of high-precision on-chip displacement sensors.

11.
Opt Lett ; 48(18): 4761-4764, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707896

RESUMO

High quality (Q) factor, tunable unidirectional guided resonances (UGRs) based on a silicon-on-lithium niobate (Si-on-LN) photonic crystal (PhC) slab are proposed and numerically investigated. The Q factors of UGRs decay quadratically with respect to the distance from the Γ point to the wave vector along the Γ-X direction, and high Q factor UGRs are obtained by moving UGR close to the Γ point. Also, a Gires-Tournois interferometer (GTI) based on a UGR with a Q factor of 9465 is numerically demonstrated, which produces a maximum group delay of 30 ps around 1.55 µm with unitary reflectance. The group delay and operation wavelengths of the GTI can be adjusted effectively by tuning the refractive index of lithium niobate (LN) and the periods of the silicon bars. Our study may find applications in PhC surface-emitting lasers, dispersion compensation, and compression of light pulses.

12.
Opt Lett ; 48(22): 5963-5966, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966763

RESUMO

We propose a type of reflectionless graphene perfect absorber (GPA) in which the reflection channel is forbidden, while the transmission channel is open. Peak absorption of 99.97% in the near-infrared is numerically demonstrated for monolayer graphene loaded on a one-dimensional silicon photonic crystal slab with rhomboid cross sections that supports parity symmetric unidirectional guided resonances (UGRs). Based on the proposed GPA, a transmissive optical modulator with a modulation depth of about 28 dB and an insertion loss of 0.31 dB by varying the Fermi energy level graphene from 0.3 eV to 0.7 eV is numerically presented. Remarkably, the design strategy can be straightforwardly applied to other two-dimensional (2D) materials. Our study may find promising applications in 2D material-based optical modulators and filters.

13.
BMC Psychiatry ; 23(1): 573, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553656

RESUMO

BACKGROUND: Workplace violence has always been a critical issue worldwide before and after the COVID-19 pandemic, which can lead to burnout and turnover. In addition, the burnout and mental stress of nurses during the COVID-19 period have been widely described. To our knowledge, no studies have examined the mediating effect of the sense of coherence on the relationship between workplace violence and burnout among Chinese nurses over time. Therefore, this study aimed to explore the relationship between workplace violence and burnout among Chinese nurses and how the sense of coherence mediates the association. METHODS: Using a convenience sampling method, 1190 nurses from 4 tertiary grade-A comprehensive hospitals were investigated between September 2021 and December 2021 in 3 provinces of China. The Workplace Violence Scale, Burnout Inventory, and Sense of Coherence scale were used to collect data. Data analysis was conducted using descriptive statistics, Pearson correlation, and regression analysis to estimate direct and indirect effects using bootstrap analysis. RESULTS: The mean total scores for workplace violence and burnout were 1.67 ± 1.08 and 47.36 ± 18.39, respectively. Workplace violence was significantly negatively correlated with the sense of coherence (r = -0.25) and positively correlated with burnout (r = 0.27). Additionally, a higher level of workplace violence was associated with higher burnout (ß = 1.13, 95% CI: 0.68 ~ 1.56). A higher sense of coherence was also associated with lower burnout (ß = -0.98, 95% CI: -1.03 ~ -0.92). Workplace violence showed an effect on burnout through a sense of coherence. The direct, indirect and total effects were 1.13, 1.88 and 3.01, respectively. The mediating effect of the sense of coherence accounted for 62.45% of the relationship between workplace violence and burnout. CONCLUSION: We found that the sense of coherence mediated most workplace violence on burnout. It is imperative for hospital managers to improve nurses' sense of coherence to reduce the occurrence of burnout during COVID-19. Future intervention studies should be designed to strengthen nurses' sense of coherence.


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Senso de Coerência , Violência no Trabalho , Humanos , População do Leste Asiático , Pandemias , Estudos Transversais , Inquéritos e Questionários , COVID-19/epidemiologia , Esgotamento Profissional/epidemiologia , Local de Trabalho , Satisfação no Emprego
14.
BMC Ophthalmol ; 23(1): 362, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605136

RESUMO

BACKGROUND: Traumatic aniridia occurs when the iris is extruded from the eye and is often accompanied by lens injuries. However, traumatic aniridia due to dislocation of the iris into the vitreous cavity without lens damage has never been reported. CASE PRESENTATION: A 30-year-old man presented with visual loss and pain for 6 h after a thin wire injured his right eyeball. Ophthalmologic examinations manifested a 2 mm full-thickness corneal laceration and total hyphema. An intact clear lens, healthy attached retina, and almost complete iris tissue in the vitreous cavity were found after resolution of hyphema the next day. Further examination revealed that the defect in the zonule below the corneal wound was the path for the iris to enter the vitreous cavity. The patient opted for nonsurgical treatment until pigment granules and opacity were observed in the vitreous cavity after 50 days. Vitrectomy was performed to remove the dislocated iris. CONCLUSIONS: The presentation of this unique case indicates that the torn iris was displaced to the vitreous cavity with an intact lens and missing local zonula instead of out the corneal laceration after a penetrating injury. The type of injury, mechanism, and force on the spot may contribute to the occurrence of this rare condition. Instead of artificial irises, tinted glasses were more appropriate treatment option for this patient. Peripheral retinal examination was essential in the management of this case. In such cases, the iris in the vitreous cavity should be resected to prevent complications.


Assuntos
Lesões da Córnea , Lacerações , Cristalino , Masculino , Humanos , Adulto , Hifema , Cristalino/cirurgia , Iris/cirurgia , Lesões da Córnea/complicações , Lesões da Córnea/diagnóstico , Lesões da Córnea/cirurgia
15.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37688099

RESUMO

Recently, cardiovascular disease has become the leading cause of death worldwide. Abnormal heart rate signals are an important indicator of cardiovascular disease. At present, the ECG signal acquisition instruments on the market are not portable and manual analysis is applied in data processing, which cannot address the above problems. To solve these problems, this study proposes an ECG acquisition and analysis system based on machine learning. The ECG analysis system responsible for ECG signal classification includes two parts: data preprocessing and machine learning models. Multiple types of models were built for overall classification, and model fusion was conducted. Firstly, traditional models such as logistic regression, support vector machines, and XGBoost were employed, along with feature engineering that primarily included morphological features and wavelet coefficient features. Subsequently, deep learning models, including convolutional neural networks and long short-term memory networks, were introduced and utilized for model fusion classification. The system's classification accuracy for ECG signals reached 99.13%. Future work will focus on optimizing the model and developing a more portable instrument that can be utilized in the field.


Assuntos
Doenças Cardiovasculares , Humanos , Análise de Sistemas , Engenharia , Aprendizado de Máquina , Memória de Longo Prazo
16.
J Transl Med ; 20(1): 81, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35135562

RESUMO

BACKGROUND: Abnormal maternal lipid concentrations are associated with increased risk of preeclampsia. However, previous studies mainly focused on fasting lipid concentrations, scarce data have been published on the relationship between postprandial triglyceride (TG) concentrations in the second trimester and the risk of preeclampsia. Our aim is to evaluate the potential of triglyceride (TG) concentrations at the time of oral lipid tolerance test (OLTT) measurement in the second trimester to predict preeclampsia and to elucidate the lipid metabolic changes related to these diseases. METHODS: This is a prospective cohort study of Pregnant women at 12-24 weeks of gestation undergone an OLTT in a university affiliated hospital between May 2019 and January 2020. Data were stratified into binaries according to the OLTT results. The receiver operating characteristic (ROC) curve analysis was conducted to determine the optimal cut-off points of TG, HDL-C, LDL-C, sd-LDL, FFA, and BG for predicting preeclampsia. RESULTS: 438 pregnant women were recruited to undergo an OLTT at 12-24 weeks of gestation. Among these, 24 women developed preeclampsia and 414 women remained normotensive. Women who subsequently developed preeclampsia had higher concentrations of 4-h postprandial TG than those who remained normotensive. In the linear logistic regression analyses of potential confounding factors, mid-trimester 4-h postprandial TG concentrations at the time of OLTT measurement were significantly higher in preeclamptic cases than in controls. CONCLUSIONS: Dyslipidemia in the second trimester of pregnancy, particularly postprandial hypertriglyceridemia, appears to be associated with an increased risk of preeclampsia. Mid-trimester 4-h postprandial TG concentration at the time of OLTT measurement may be a potential predictive marker of preeclampsia. Trial registration Data of registration: 2018/10/15. Date of initial participant enrollment: 2019/05/01. Clinical trial identification number: chiCTR1800018884. URL of the registration site: http://www.chictr.org.cn/showproj.aspx?proj=25526 . Data sharing information: The data including individual participant data, detailed study protocols, statistical analysis plans will be shared upon request to the corresponding author.


Assuntos
Hipertrigliceridemia , Pré-Eclâmpsia , Feminino , Humanos , Período Pós-Prandial , Pré-Eclâmpsia/diagnóstico , Gravidez , Estudos Prospectivos , Triglicerídeos
17.
Opt Express ; 30(24): 43741-43751, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523066

RESUMO

In the paper, a type of phase change metamaterial for tunable infrared stealth and camouflage is proposed and numerically studied. The metamaterial combines high temperature resistant metal Mo with phase-changing material GST and can be switched between the infrared "stealthy" and "non-stealthy" states through the phase change process of the GST. At the amorphous state of GST, there is a high absorption peak at the atmospheric absorption spectral range, which can achieve infrared stealth in the atmospheric window together with good radiative heat dissipation in the non-atmospheric window. While at the crystalline state of GST, the absorption peak becomes broader and exhibits high absorption in the long-wave infrared atmospheric window, leading to a "non-stealthy" state. The relationship between the infrared stealth performance of the structure with the polarization and incident angle of the incident light is also studied in detail. The proposed infrared stealth metamaterial employs a simple multilayer structure and could be fabricated in large scale. Our work will promote the research of dynamically tunable, large scale phase change metamaterials for infrared stealth as well as energy and other applications.

18.
Opt Express ; 30(23): 41110-41117, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366596

RESUMO

The high saturation current density and ultrafast heating modulation of graphene makes it a competitive candidate for future thermal emission source. However, the low emissivity and easy oxidation under high temperature in air limit graphene application in the spectral range from the visible to near infrared. Here, we report a visible graphene thermal emitter based on the metal Fabry-Pérot (FP) cavity, which can greatly enhance the emissivity of graphene at wavelength around 637 nm and protect graphene from oxidation. We investigate the temperature characteristics of the emitter, and find the temperature of hot electrons in graphene is much higher than that of graphene lattice. Moreover, we also demonstrate the wavelength and intensity of graphene emission could be controlled by tuning the dielectric thickness between two gold layers. These results are helpful in the development of advanced graphene electro-thermal emission controlling application.

19.
Opt Lett ; 47(21): 5481-5484, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219249

RESUMO

A typical optomechanical system is a cavity with one movable mirror and one fixed mirror. However, this configuration has been considered incapable of integrating sensitive mechanical elements while maintaining high cavity finesse. Although the membrane-in-the-middle solution seems to be able to overcome this contradiction, it introduces additional components that will lead to unexpected insertion loss, resulting in reduced cavity quality. Here we propose a Fabry-Perot optomechanical cavity composed of an ultrathin suspended Si3N4 metasurface and a fixed Bragg grating mirror, with a measured finesse up to 1100. Transmission loss of this cavity is very low as the reflectivity of this suspended metasurface tends to unity around 1550 nm. Meanwhile, the metasurface has a millimeter-scale transverse dimension and a thickness of only 110 nm, which guarantees a sensitive mechanical response and low cavity diffraction loss. Our metasurface-based high-finesse optomechanical cavity has a compact structure, which facilitates the development of quantum and integrated optomechanical devices.

20.
Mol Psychiatry ; 26(6): 2070-2081, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32398722

RESUMO

Substantial genetic liability is shared across psychiatric disorders but less is known about risk variants that are specific to a given disorder. We used multi-trait conditional and joint analysis (mtCOJO) to adjust GWAS summary statistics of one disorder for the effects of genetically correlated traits to identify putative disorder-specific SNP associations. We applied mtCOJO to summary statistics for five psychiatric disorders from the Psychiatric Genomics Consortium-schizophrenia (SCZ), bipolar disorder (BIP), major depression (MD), attention-deficit hyperactivity disorder (ADHD) and autism (AUT). Most genome-wide significant variants for these disorders had evidence of pleiotropy (i.e., impact on multiple psychiatric disorders) and hence have reduced mtCOJO conditional effect sizes. However, subsets of genome-wide significant variants had larger conditional effect sizes consistent with disorder-specific effects: 15 of 130 genome-wide significant variants for schizophrenia, 5 of 40 for major depression, 3 of 11 for ADHD and 1 of 2 for autism. We show that decreased expression of VPS29 in the brain may increase risk to SCZ only and increased expression of CSE1L is associated with SCZ and MD, but not with BIP. Likewise, decreased expression of PCDHA7 in the brain is linked to increased risk of MD but decreased risk of SCZ and BIP.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno Bipolar , Esquizofrenia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno Bipolar/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética
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