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Dielectric nanostructures exhibit low-loss electrical and magnetic resonance, making them ideal for quantum information processing. In this study, the periodic double-groove silicon nanodisk (DGSND) is used to support the anapole state. Based on the distribution properties of the electromagnetic field in anapole states, the anapoles are manipulated by cutting the dielectric metamaterial. Quantum dots (QDs) are used to stimulate the anapole and control the amplification of the photoluminescence signal within the QDs. By opening symmetrical holes in the long axis of the nanodisk in the dielectric metamaterial, the current distribution of Mie resonance can be adjusted. As a result, the toroidal dipole moment is altered, leading to an enhanced electric field (E-field) and Purcell factor. When the dielectric metamaterial is deposited on the Ag substrate separated by the silicon dioxide (SiO2) layer, the structure exhibits ultra-narrow perfect absorption with even higher E-field and Purcell factor enhancement compared to silicon (Si) nanodisks.
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Edge enhancement, as an important part of image processing, has played an essential role in amplitude-contrast and phase-contrast object imaging. The edge enhancement of three-dimensional (3D) vortex imaging has been successfully implemented by Fresnel incoherent correlation holography (FINCH), but the background noise and image contrast effects are still not satisfactory. To solve these issues, the edge enhancement of FINCH by employing Bessel-like spiral phase modulation is proposed and demonstrated. Compared with the conventional spiral phase modulated FINCH, the proposed technique can achieve high-quality edge enhancement 3D vortex imaging with lower background noise, higher contrast and resolution. The significantly improved imaging quality is mainly attributed to the effective sidelobes' suppression in the generated optical vortices with the Bessel-like modulation technique. Experimental results of the small circular aperture, resolution target, and the Drosophila melanogaster verify its excellent imaging performance. Moreover, we also proposed a new method for selective edge enhancement of 3D vortex imaging by breaking the symmetry of the spiral phase in the algorithmic model of isotropic edge enhancement. The reconstructed images of the circular aperture show that the proposed method is able to enhance the edges of the given objects selectively in any desired direction.
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Graphene and its derivatives are widely used in the field of energy conversion and management due to their excellent physical and chemical properties. In this paper, ultra-thin graphite film (GF) with thickness of 100-150 nm prepared by chemical vapor deposition was transferred to oxygen plasma-treated polyimide (PI) substrate as flexible heating film. The electrothermal and photothermal properties of GF on PI substrates with different treatment time were studied. The experimental results show that the PI substrate pretreated by oxygen plasma can change the surface morphology of GF, increase its electrical conductivity and light absorption capacity, and significantly improve the electrothermal and photothermal properties of GF heater. Under the low applied voltage of 5 V (power density of 0.81 W cm-2), the surface temperature of GF on 40 min plasma-treated PI substrate can rise to 250 °C, which is nearly 50 °C higher than that of GF on untreated PI substrate. When 100 nm thick commercial multilayer graphene film (MLG) is used, plasma-treated PI substrate can increase the electric heating temperature of MLG by 70 °C. In terms of photothermal performance, the surface temperature of GF on 50 min plasma-treated PI substrate can reach 73 °C under one Sun irradiation, which is 8 °C higher than that on untreated substrate. The experimental results are in good agreement with the simulation research. Our strategy has important implications for the development of efficient and energy-saving graphene/graphite-based heating films for advanced electrothermal and photothermal conversion devices.
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Regional atrophy and metal deposition are typical manifestations in Wilson's disease, but their relationship has not been systematically investigated. We aim to investigate the association of regional brain atrophy and metal deposition in the deep gray matter nucleus at MRI in Wilson's disease. We acquired the structural and susceptibility mapping and performed a cross-sectional comparison of volume and susceptibility in deep gray matter nucleus. The most extensive and severe atrophy was detected in brain regions in neuro-Wilson's disease, as well as the most widespread and heaviest metal deposits. Metal deposits were significantly negatively correlated with volume in the bilateral thalamus, caudate, and putamen. None of correlation was found between the clinical score with volume or susceptibility in the focused regions. In the 1-year follow-up analysis, the volume of right thalamus, globus pallidus, and brainstem and the susceptibility of the left caudate have decreased significantly as the symptom improvement. In Wilson's disease, phenotypes have varied scope and extend of volumetric atrophy and metal deposits. This study is expected to take the lead in revealing that in neuro-Wilson's disease, greater regional atrophy associated with heavier metal deposits in Wilson's disease. Moreover, after 1-year treatment, the imaging data have changed as the patient's condition improvement.
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Degeneração Hepatolenticular , Humanos , Degeneração Hepatolenticular/diagnóstico por imagem , Degeneração Hepatolenticular/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Estudos Transversais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Atrofia/patologia , Imageamento por Ressonância Magnética/métodosRESUMO
Young adults thrust into the role of caregiving for parents with young-onset dementia (YOD) face unique challenges during their formative years. While existing research acknowledges the crucial role of young adult caregivers, a gap persists in understanding how this group experiences and redefines their identity amidst these circumstances, along with the psychological and societal challenges encountered. This knowledge deficit hinders the identification of suitable social support, adversely affecting the personal growth and well-being of these young adult caregivers. In this single-case study, we used a combination of a semi-structured interview and photovoice to explore the journey of a 19-year-old caregiver, Alice, whose mother had been diagnosed with dementia in the preceding 3 years. Through this unique perspective, we aimed to illuminate how caregiving for a mother with YOD may profoundly redefine familial roles and relationships. Over 3 months, Alice captured significant life moments through photography, selecting meaningful images for bi-weekly meetings. These images served as pivotal themes, triggering in-depth conversations during subsequent interviews to provide nuanced insights into her life experiences. Findings reveal four major themes faced by a young caregiver: (1) challenges adapting to an unexpected role, (2) navigating the complex emotional terrain of losing a loved one to YOD, (3) prioritizing the well-being of the healthy parent, and (4) expressing a profound desire for both informal and formal support. These results underscore the intricate identity and emotional challenges faced by young adult caregivers, emphasizing the urgency of addressing their unique needs through family-centered systemic support services.
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BACKGROUND: Although China has the largest population of persons with dementia, there is no validated tool available to accurately assess formal caregivers' competence in dementia care in long-term care settings. Appropriately assessing nursing staff's level of competence in dementia care is the first step to develop precision training interventions to improve the quality of dementia care. The Sense of Competence in Dementia Care Staff scale (SCIDS) is a user-friendly tool with satisfactory reliability and validity. We adapted SCIDS into a Chinese version (SCIDS-C) and validated its uses in China's socio-cultural context to assess nursing staff's capability and competence in dementia care at nursing homes. AIMS: We aimed to adapt and psychometrically test the tool among frontline nursing staff in long-term care settings in China. METHODS: The research employed a correlational design with repeated measures. In translation section, we adapted and tailored the original scale in the cultural and social context in China's nursing homes. The scale's adaptation consists of translating adaptation and semantic equivalence. In psychometric testing phase, we tested the validity and reliability of the scale with 174 nursing staff conveniently from six nursing homes. Construct validity was tested using exploratory factor analysis (EFA), including principal component analysis and maximum variance rotation method. Reliability was tested using Cronbach's alpha value and intraclass correlation coefficient (ICC). RESULTS: The SCIDS-C has 17 items, which belong to the two sub-scales, the Relationship-Centered Care(RCC) and Professional Care(PC). The Cronbach's alpha value was 0.88, showing a good internal consistency. The full scale's value of ICC was 0.94 which indicated good reliability. Exploratory factor analysis(EFA) extracted 2 common factors in each sub-scale, cumulative variance contribution rate was 56.71% and 53.92%, respectively. The named four factors are the same as the Sense of Competence in Dementia Care Staff (SCIDS) scale in English, including Building Relationships, Sustaining Personhood, Professionalism and Care Challenges. CONCLUSION: The SCIDS-C has shown good reliability and validity. It can be used as an appropriate tool to evaluate the competence of nursing care staff to provide dementia care for residents in nursing homes.
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Demência , Casas de Saúde , Humanos , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , China/epidemiologia , Demência/diagnóstico , Demência/terapiaRESUMO
Metamaterial with hyperbolic dispersion properties can effectively manipulate plasmonic resonances. Here, we designed a hyperbolic metamaterial (HMM) substrate with a near-zero dielectric constant in the near-infrared region to manipulate the plasmon resonance of the nano-antenna (NA). For NA arrays, tuning the equivalent permittivity of HMM substrate by modifying the thickness of Au/diamond, the wavelength range of plasmon resonance can be manipulated. When the size of the NA changes within a certain range, the spectral position of the plasmon resonance will be fixed in a narrow band close to the epsilon-near-zero (ENZ) wavelength and produce a phenomenon similar to "pinning effect." In addition, since the volume plasmon polaritons (VPP) mode is excited, it will couple with the localized surface plasmon (LSP) mode to generate a spectrum splitting. Therefore, the plasmon resonance is significantly affected and can be precisely controlled by designing the HMM substrate.
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Due to the topological charge-independent doughnut spatial structure as well as the association of orbital angular momentums, perfect vortex beams promise significant advances in fiber communication, optical manipulation and quantum optics. Inspired by the development of planar photonics, several plasmonic and dielectric metasurfaces have been constructed to generate perfect vortex beams, instead of conventional bulky configuration. However, owing to the intrinsic Ohmic losses and interband electron transitions in materials, these metasurface-based vortex beam generators only work at optical frequencies up to the visible range. Herein, using silicon nitride nanopillars as high-efficiency half-wave plates, broadband and high-performance metasurfaces are designed and demonstrated numerically to directly produce perfect vortex beams in the ultraviolet region, by combining the phase profiles of spiral phase plate, axicon and Fourier transformation lens based on geometric phase. The conversion efficiency of the metasurface is up to 86.6% at the design wavelength. Moreover, the influence of several control parameters on perfect vortex beam structures is discussed. We believe that this ultraviolet dielectric generator of perfect vortex beams will find many significant applications, such as high-resolution spectroscopy, optical tweezer and on-chip communication.
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Plasmon induced transparency (PIT), known as the coupling of plasmon modes in metamaterials, has attracted intensive research interests in photonic applications. In this work, a PIT-like transparency is realized via the strong coupling of plasmonic dipole and epsilon-near-zero (ENZ) mode. Two types of metasurfaces, namely the gold nanoantenna and dolmen-like metasurface, are designed with an integrated ENZ material aluminum doped zinc oxide (AZO) film. Simulations with the finite element method (FEM) demonstrate that single and double transparent windows are achieved respectively. The adjustments of the peak position and transmittance of transparent windows via the structure parameters and the AZO film thickness are further investigated. This work provides an alternative coupling scheme of realizing PIT-like transparency with simple metasurface design, and offers great potential for future metamaterial applications.
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Semi-skilled or unskilled nursing care aides primarily provide direct care to residents in long-term care (LTC) facilities in China and many other countries around the world. There has been a significantly increased commitment from nurses and other formally trained professionals to provide person-centered care (PCC) for people with dementia (PwD). However, it is still unclear how nursing care aides who provide direct care to older residents with dementia understand and adopt PCC in their daily work. It is of utmost importance to understand person-centered dementia care from the perspectives of care aides, and to identify implications to facilitate and sustain their efforts in providing quality care for older residents with dementia. We found that the seemingly beneficial mental models used by care aides in their work can hinder them from playing a more adaptive role in tailoring their care to the needs of older residents. Infantilizing older residents with dementia and labeling them using mother wit can prevent meaningful, equal, and person-centered conversations between both parties. Care aides do not have regular formal interactions and sensemaking with nurses and other professionals in nursing homes. Increasing interactions and communication between care aides and health care professionals in nursing homes can lead to insight for changing the approach to in-service training to achieve better acceptance by care aides. The current study derives implications for operationalizing and embedding the principles of PCC in daily care.
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Demência , Assistência de Longa Duração , Comunicação , Demência/terapia , Humanos , Capacitação em Serviço , Casas de SaúdeRESUMO
Introduction: It is elusive to compare the efficacy and safety of abrocitinib 100 mg versus 200 mg once daily in patients with atopic dermatitis. Aim: This meta-analysis aims to explore the influence of abrocitinib 100 mg versus 200 mg on the treatment of atopic dermatitis. Material and methods: Several databases including PubMed, EMbase, Web of science, EBSCO, and Cochrane library were systematically searched through July 2021. We included randomized controlled trials (RCTs) assessing the effect of abrocitinib 100 mg versus 200 mg for patients with atopic dermatitis. Results: Four RCTs were included in the meta-analysis. Compared with abrocitinib 100 mg for atopic dermatitis, abrocitinib 200 mg had a remarkably positive impact on IGA response (OR = 1.78; 95% CI: 1.39-2.28; p < 0.00001), EASI-75 (OR = 2.03; 95% CI: 1.60-2.57; p < 0.00001), NRS response (OR = 1.97; 95% CI: 1.27-3.08; p = 0.003), and adverse events (OR = 1.43; 95% CI: 1.11-1.84; p = 0.005), but it showed no obvious influence on serious adverse events (OR = 0.59; 95% CI: 0.25-1.37; p = 0.22). Conclusions: Abrocitinib 200 mg is better than abrocitinib 100 mg for the treatment of atopic dermatitis.
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In this work, we present an efficient polarization conversion device via using a hollow graphene metasurface. The platform can simultaneously realize a series of excellent performances, including the broadband x-to-y cross polarization conversion (CPC) function with near unity polarization conversion ratio (PCR), dual-frequency linear-to-circular polarization conversion (LTC-PC) function, and highly sensitive polarization conversion function manipulation under wide oblique incidence angle range. For instance, the proposed device obtains an x-to-y CPC function with the bandwidth up to 1.83 THz (χPCR ≥98.8%). Moreover, the x-to-y CPC function can be switched to LTC-PC function via artificially tuning the Fermi energy of graphene. The maximal frequency shift sensitivity (S) of polarization conversion function reaches 23.09 THz/eV, suggesting a frequency shift of 2.309 THz for the LTC-PC function when the chemical potential is changed by 0.1 eV. Based on these superior performances, the polarization converter can hold potential applications in integrated and compact devices, such as polarization sensor, switches and other optical polarization control components.
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An efficient thermal emitter for selective radiative cooling is realized with vanadium dioxide metamaterials. The novel structure consists of patterned VO2 metamaterials on the multilayer substrate and a composite layer on it. To obtain the enhanced emissivity, the influence of the top composite layer and external thermal stimuli are comprehensively optimized. The emissivity can reach up to 0.952 in the metallic phase of VO2 with a composite layer in the atmospheric window, which is due to strong localization of the electric field in the cavity. The influence on the emissivity with different incident angles and geometric parameters is investigated elaborately. Finally, the cooling power is calculated and achieves a high value of 710W/m2 at 383 K, which is significantly higher than that of previous works. Thus, our proposed tunable emitter with high performance will be beneficial to the dynamic radiative cooling system and may open a potential application in building cooling and intelligent windows.
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In this work, a feasible way for perfect absorption in the whole solar radiance range is numerically demonstrated via the multiple resonances in a 600-nm-thick refractory prismoid. Under the standard AM 1.5 illumination, the measured solar energy absorption efficiency reaches 99.66% in the wavelength range from 280â nm to 4000â nm, which indicates only a rather small part of solar light (0.34%) escaped. The record harvesting efficiency directly results from the near-unity absorption for the multi-layer refractory resonators, which can simultaneously benefit from the multi-resonant behaviors of the structure and the broadband resonant modes by the material intrinsic features. The absorption including the intensity and frequency range can be adjusted via the structural features. These findings can hold wide applications in solar energy related optoelectronics such as the thermal-photovoltaics, photo-thermal technology, semiconductor assisted photo-detection, ideal thermal emitters, etc.
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In this work, we propose and demonstrate a near-unity light absorber in the ultra-violet to near-infrared range (300-1100â nm) with the average efficiency up to 97.7%, suggesting the achievement of black absorber. The absorber consists of a wavy surface geometry, which is formed by the triple-layer of ITO (indium tin oxide)-Ge (germanium)-Cu (copper) films. Moreover, the minimal absorption is even above 90% in the wide wavelength range from 300â nm to 1015â nm, suggesting an ultra-broadband near-perfect absorption window covering the main operation range for the conventional semiconductors. Strong plasmonic resonances and the near-field coupling effects located in the spatially geometrical structure are the key contributions for the broadband absorption. The absorption properties can be well maintained during the tuning of the polarization and incident angles, indicating the high tolerance in complex electromagnetic surroundings. These findings pave new ways for achieving high-performance optoelectronic devices based on the light absorption over the full-spectrum energy gap range.
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In this work, we numerically demonstrate a new facile strategy for all-dielectric broadband optical perfect absorbers. A monolayer refractory titanium oxide and nitride (TiN/TiO2) core-shell nanowires array is used to form the grating on the opaque TiN substrate. Multiple resonant absorption bands are observed in the adjacent wavelength range, which therefore leads to the formation of an ultra-broadband absorption window from the visible to the infrared regime. The maximal absorption reaches 95.6% and the average absorption efficiency in the whole range (0.5-1.8 µm) is up to 85.4%. Moreover, the absorption bandwidth can be feasibly adjusted while the absorption efficiency can be still maintained in a high level via tuning the polarization state. Furthermore, the absorption window is observed to be highly adjustable in the wavelength range, showing a nearly linear relationship to the shell's index. These features not only confirm the achievement of the broadband perfect absorption but also introduce feasible ways to artificially manipulate the absorption properties, which will hold wide applications in metal-free plasmonic optoelectronic devices such as the solar harvesting, photo-detection, and thermal generation and its related bio-medical techniques.
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Metamaterial absorbers have attracted great attention over the past few years and exhibited a promising prospect in solar energy harvesting and solar thermophotovoltaics (STPVs). In this work, we introduce a solar absorber scheme, which enables efficient solar irradiance harvesting, superb thermal robustness and high solar thermal energy conversion for STPV systems. The optimum structure demonstrates an average absorbance of 97.85% at the spectral region from 200â nm to 2980â nm, indicating the near-unity absorption in the main energy range of the solar radiance. The solar-thermal conversion efficiencies surpassing 90% are achieved over an ultra-wide temperature range (100-800 °C). Meanwhile, the analysis indicates that this metamaterial has strong tolerance for fabrication errors. By utilizing the simple two-dimensional (2D) titanium (Ti) gratings, this design is able to get beyond the limit of costly and sophisticated nanomanufacturing techniques. These impressive features can hold the system with wide applications in metamaterial and other optoelectronic devices.
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Understanding energy transfer via near-field thermal radiation is essential for applications such as near-field imaging, thermophotovoltaics and thermal circuit devices. Evanescent waves and photon tunneling are responsible for the near-field energy transfer. In bulk noble metals, however, surface plasmons do not contribute efficiently to the near-field energy transfer because of the mismatch of wavelength. In this paper, a giant near-field radiative heat transfer rate that is orders-of-magnitude greater than the blackbody limit between two ultrathin metallic films is demonstrated at nanoscale separations. Moreover, different physical origins for near-field thermal radiation transfer for thick and thin metallic films are clarified, and the radiative heat transfer enhancement in ultrathin metallic films is proved to come from the excitation of surface plasmons. Meanwhile, because of the inevitable high sheet resistance of ultrathin metal films, the heat transfer coefficient is 4600 times greater than the Planckian limit for the separation of 10 nm in ultrathin metallic films, which is the same order or even greater than that in other 2D materials with low carrier density. Our work shows that ultrathin metallic films are excellent materials for radiative heat transfer, which may find promising applications in thermal nano-devices and thermal engineering.
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Although several lines of evidence existed suggesting that Mortalin was linked with survival in malignant tumors; it has been barely described regarding the prognostic involvement of its expression in hepatocellular carcinoma (HCC). Herein, to understand the prognostic meaning of Mortalin expression, Immunohistochemistry was undertaken to observe the immunohistochemical characteristics of Mortalin on HCC tissue microarray consisting of 90 cases of HCC and its paired normal control dots, followed by detailed statistical analysis with the accompanying clinicopathological variables available, including gender, age, tumor size, differentiation, cirrhosis, vascular invasion, clinical stage, T classification and intrahepatic metastases. Meanwhile, Kaplan-Meier survival curve was plotted to analyze the prognostic difference for patients with high and low expression of Mortalin. It was exhibited that Mortalin was over-expressed in HCC tissues relative to paired normal control and elevated Mortalin significantly correlated with vascular invasion, clinical stage and intrahepatic metastasis. Kaplan-Meier survival analysis revealed that Mortalin was remarkably associated with overall survival and disease-free survival. Multivariate Cox regression analysis showed that expression of Mortalin was an independent prognostic factor in HCC. Collectively, the data we provided here support the prognostic prediction value of Mortalin in HCC.
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Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/patologia , Proteínas de Choque Térmico HSP70/biossíntese , Neoplasias Hepáticas/patologia , Proteínas Mitocondriais/biossíntese , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
We theoretically study a tunable reflective focusing lens, based on graphene metasurface, which consists of rectangle aperture array. Dynamic control of either the focal intensity or focal length for terahertz circular polarized waves can be achieved by uniformly tuning the graphene Fermi energy. We demonstrate the graphene apertures with the same geometry; however, spatially varying orientations can only control the focal intensity. To change the focal length, the spatially varying aperture lengths are also required. A comparative study between the metalenses, which generate only geometric or both gradient and geometric phase changes, has shown that the apertures' spatially varying length distribution is the key factor for determining the modulation level, rather than the focal length's modulation range. This kind of metalens provides tunable, high-efficiency, broadband, and wide-angle off-axis focusing, thereby offering great application potential in lightweight and integrated terahertz devices.