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Strong coupling between resonantly matched surface plasmons of metals and excitons of quantum emitters results in the formation of new plasmon-exciton hybridized energy states. In plasmon-exciton strong coupling, plasmonic nanocavities play a significant role due to their ability to confine light in an ultrasmall volume. Additionally, two-dimensional transition metal dichalcogenides (TMDCs) have a significant exciton binding energy and remain stable at ambient conditions, making them an excellent alternative for investigating light-matter interactions. As a result, strong plasmon-exciton coupling has been reported by introducing a single metallic cavity. However, single nanoparticles have lower spatial confinement of electromagnetic fields and limited tunability to match the excitonic resonance. Here, we introduce the concept of catenary-shaped optical fields induced by plasmonic metamaterial cavities to scale the strength of plasmon-exciton coupling. The demonstrated plasmon modes of metallic metamaterial cavities offer high confinement and tunability and can match with the excitons of TMDCs to exhibit a strong coupling regime by tuning either the size of the cavity gap or thickness. The calculated Rabi splitting of Au-MoSe2 and Au-WSe2 heterostructures strongly depends on the catenary-like field enhancement induced by the Au cavity, resulting in room-temperature Rabi splitting ranging between 77.86 and 320 meV. These plasmonic metamaterial cavities can pave the way for manipulating excitons in TMDCs and operating active nanophotonic devices at ambient temperature.

Gas sensing is essential for detecting and measuring gas concentrations across various environments, with applications in environmental monitoring, industrial safety, and healthcare. The integration of two-dimensional (2D) materials, organic materials, and metal oxides has significantly advanced gas sensor technology, enhancing its sensitivity, selectivity, and response times at room temperature. This review examines the progress in optically activated gas sensors, with emphasis on 2D materials, metal oxides, and organic materials, due to limited studies on their use in optically activated gas sensors, in contrast to other traditional gas-sensing technologies. We detail the unique properties of these materials and their impact on improving the figures of merit (FoMs) of gas sensors. Transition metal dichalcogenides (TMDCs), with their high surface-to-volume ratio and tunable band gap, show exceptional performance in gas detection, especially when activated by UV light. Graphene-based sensors also demonstrate high sensitivity and low detection limits, making them suitable for various applications. Although organic materials and hybrid structures, such as metal–organic frameworks (MoFs) and conducting polymers, face challenges related to stability and sensitivity at room temperature, they hold potential for future advancements. Optically activated gas sensors incorporating metal oxides benefit from photoactive nanomaterials and UV irradiation, further enhancing their performance. This review highlights the potential of the advanced materials in developing the next generation of gas sensors, addressing current research gaps and paving the way for future innovations.

Silicon carbide (SiC) is widely used in abrasives, heating devices, light emitting diodes and high-power electronics, because of its unique physical-chemical properties including high hardness, high melting point, excellent thermal conductivity, and wide bandgap. In recent years, its color centers have also been used as potential sources of single photons. Given that borides and carbides are refractory materials, we decided to study a heterostructure formed by an n-doped silicon carbide substrate and a layer of tantalum monoboride (TaB) for near ultraviolet (UV) photodetection. It is shown that the addition of TaB creates a rectifying device that can handle currents higher than 300 mA, showing its potential for high-power optoelectronic devices. The detector also has a high responsivity of 2.9 A/W at the free-space wavelength of 405 nm and a fast frequency response of 610 kHz. The high performance of the detector is attributed to the high thermal and electrical conductivity, large bandgap of SiC, and its moderately close match in atomic arrangement with TaB. Such heterostructure offers a simple method to produce high-performance near UV photodetectors operating under hard conditions such as high power, high temperature and corrosive or oxidizing environments.

Targeted nanoparticle delivery to sites of interest is important for targeted therapeutics. Here, the authors improve the targeting efficiency of antibodies on nanoparticles using a monobody adapter to correctly orientate the antibody to preserve targeting function and demonstrate application in targeting the vascular endothelium of human kidneys.

This study presents a theoretical framework for a radiative thermal memristor (RTM), utilizing Tungsten-doped vanadium dioxide (WVO) as the phase-change material (PCM) and silicon carbide (SiC) in the far-field regime. The behavior of the RTM is depicted through a Lissajous curve, illustrating the relationship between net flux (Q) and a periodically modulated temperature difference ΔT(t). It is established that temperature variations in the memristance (M) of the RTM form a closed loop, governed by PCM hysteresis. The analysis explores the impact of thermal conductivity contrast (r) and periodic thermal input amplitude (θ) on the Q–ΔT curve and the M–ΔT curve and negative differential thermal resistance (NDTR), revealing notable effects on the curve shapes and the emergence of NDTR. An increasing r leads to changes in the Lissajous curve’s shape and enhances the NDTR influence, while variations in both r and (θ) significantly affect the Q values and Lissajous curve amplitudes. In the M–ΔT curve, the height is linked to thermal conductivity contrast (r), with increasing r resulting in higher curve heights.

In this paper, we analyze the performance of two tantalum-based boride (TaB and TaB2) microparticles as potential saturable absorbers for high-power fiber lasers. Both materials are ultrahigh temperature ceramics with melting points above 3000 °C, but with different crystalline structures: TaB has an orthorhombic structure (nearly isotropic), whereas TaB2 has a hexagonal structure (uniaxial, anisotropic). Despite their different crystalline structures, the microparticles have a similar low fluence attenuation (between 2.3 and 2.60 dB/μm) and modulation depths (around 2.0 dB/μm), but remarkable different saturation fluences: TaB has a saturation fluence of 160 μJ/cm2, whereas TaB2 has a saturation fluence of 110 μJ/cm2. The measured damage thresholds are 112 and 106 mJ/cm2/pulse for TaB and TaB2, respectively. When incorporated to a fiber laser, the materials produce pulses with durations of 345 ns, lower than those reported by our group in previous papers. The results show that the materials can find potential applications in high-power Q-switched lasers.

Objective: To assess the agreement between the results of the Subjective Global Nutritional Assessment questionnaire, adapted for children and adolescents of the Brazilian population, and the nutritional status assessment method through growth curves and the classification of the World Health Organization in a pediatric hospital service. Methods: This was an analytical, quantitative, cross-sectional study. During the data collection period, the nutritional status of all patients from 0 to 12 years of age, admitted to the pediatric unit of a university hospital, was concomitantly assessed according to the Subjective Global Nutritional Assessment and World Health Organization curves. To determine the assessment and agreement between these methods, the Kappa and Kendall coefficients were used, respectively, considering a significance level of 5%. Results: Sixty-one children participated, with a predominance of males. It was observed that the highest frequency of equivalent results occurred among the group classified as well nourished, and that only the height/age variable showed a close agreement between the methods. Additionally, there was a good correlation only for the weight/height variable between the assessment tools used. Conclusion: Due to the low agreement between the methods, the combination of both may be beneficial for the nutritional assessment of pediatric patients, collaborating with the early diagnosis of nutritional alterations and facilitating the use of adequate dietary therapy. Resumo: Objetivo: Avaliar a concordância entre os resultados do questionário da Avaliação Nutricional Subjetiva Global adaptado para crianças e adolescentes da população brasileira e do método de avaliação do estado nutricional por meio de curvas de crescimento e a classificação da Organização Mundial da Saúde em um serviço pediátrico hospitalar. Métodos: Trata-se de um estudo analítico, quantitativo, de caráter transversal. Durante o período de coleta de dados, foi avaliado o estado nutricional de todos os pacientes de zero a doze anos admitidos na Enfermaria de Pediatria de um hospital universitário segundo a Avaliação Nutricional Subjetiva Global as curvas da Organização Mundial da Saúde, concomitantemente. Para determinar a avaliação e a concordância entre estes métodos, os coeficientes de Kappa e de Kendall foram utilizados, respectivamente, considerando nível de significância de 5%. Resultados: Participaram do trabalho 61 crianças, com predominância do sexo masculino. Observou-se que a maior frequência de resultados iguais ocorreu entre o grupo classificado como bem nutrido, e que somente a variável altura/idade demonstrou íntima concordância entre os métodos. Além disso, verificou-se uma boa correlação somente para a variável peso/altura entre os instrumentos utilizados. Conclusão: Devido à baixa concordância entre os métodos, a combinação de ambos pode ser benéfica para a avaliação nutricional dos pacientes pediátricos colaborando com o diagnóstico precoce de alterações nutricionais, facilitando a aplicação do tratamento dietoterápico adequado. Keywords: Nutritional status, Nutritional assessment, Infant, Child nutrition, Child nutrition science, Palavras-chave: Estado nutricional, Avaliação nutricional, Lactente, Nutrição da criança, Ciências da nutrição infantil

Objective: To evaluate the quality of the human milk expressed at home and at a human milk bank. Methods: This a retrospective, analytical, and observational study, performed by assessing titratable acidity records and the microbiological culture of 100 human milk samples expressed at home and at a human milk bank, in 2014. For the statistical analysis, generalized estimating equations (GEE) and the chi-squared test were used. Results: When comparing the two sample groups, no significant difference was found, with 98% and 94% of the samples being approved among those collected at the milk bank and at home, respectively. No main interaction effect between local and titratable acidity records (p = 0.285) was observed, and there was no statistically significant difference between the expected and observed values for the association between the collection place and the microbiological culture results (p = 0.307). Conclusions: The quality of human milk expressed at home and at the milk bank are in agreement with the recommended standards, confirming that the expression of human milk at home is as safe as expression at the human milk bank, provided that the established hygiene, conservation, storage, and transport standards are followed. Resumo: Objetivo: Avaliar a qualidade do leite humano ordenhado em domicílio e no Banco de Leite Humano. Métodos: Estudo retrospectivo, realizado por meio da avaliação dos registros da acidez titulável e dos resultados de cultura microbiológica de 100 amostras de leite humano ordenhado em domicílio e em um Banco de Leite Humano, no ano de 2014. Para análises estatísticas foram utilizadas as Equações de Estimação Generalizadas (Generalized Estimating Equations - GEE) e o teste Qui-quadrado. Resultados: Na comparação dos dois grupos de amostras, não foi detectada diferença significativa, sendo que 98% e 94% das amostras foram aprovadas entre as coletadas no Banco de Leite e em domicílio, respectivamente. Não foi observado efeito principal de interação entre local e grau de acidez titulável (p = 0,285) e não se constatou diferença estatisticamente significante entre os valores observados e esperados para associação entre local de coleta e o resultado da cultura microbiológica (p = 0,307). Conclusões: A qualidade do leite humano ordenhado em domicílio e no Banco de Leite Humano estão de acordo com o padrão preconizado, comprovando que a ordenha de leite humano em domicílio é tão segura quanto a ordenha no Banco de Leite Humano, desde que sejam seguidas as normas de higiene, conservação, armazenamento e transporte estabelecidas. Keywords: Human milk, Breast milk expression, Milk banks, Housing, Quality control, Palavras-chave: Leite humano, Extração de leite, Bancos de Leite, Habitação, Controle de qualidade

Fast detection of near-infrared (NIR) photons with high responsivity remains a challenge for photodetectors. Germanium (Ge) photodetectors are widely used for near-infrared wavelengths but suffer from a trade-off between the speed of photodetection and quantum efficiency (or responsivity). To realize a high-speed detector with high quantum efficiency, a small-sized photodetector efficiently absorbing light is required. In this paper, we suggest a realization of a dielectric metasurface made of an array of subwavelength germanium PIN photodetectors. Due to the subwavelength size of each pixel, a high-speed photodetector with a bandwidth of 65 GHz has been achieved. At the same time, high quantum efficiency for near-infrared illumination can be obtained by the engineering of optical resonant modes to localize optical energy inside the intrinsic Ge disks. Furthermore, small junction capacitance and the possibility of zero/low bias operation have been shown. Our results show that all-dielectric metasurfaces can improve the performance of photodetectors.

Gold nano-antennas with silica substrate may not be suitable for high power applications such as heat resisted magnetic recording, solar thermophotovoltaics, and nano-scale heat transfer systems. When a laser beam reaches to these nano-antennas, part of the light is absorbed by the metallic regions, leading to a temperature rise of the device. If these devices reach a temperature beyond its Tamman temperature (the temperature at which sintering of atoms or molecules start to occur), the antenna can be damaged. One strategy to allow the antenna to work at higher fluences (energy density) is to employ substrates that can quickly carry the heat away from the antennas. In this paper, we show that high thermal conductivity substrates, such as diamond, can allow the antenna to withstand 20 times higher fluence than a low thermal conductivity silica substrate.

Objective: Theories about how couples help each other to cope with stress, such as the systemic transactional model of dyadic coping, suggest that the cultural context in which couples live influences how their coping behavior affects their relationship satisfaction. In contrast to the theoretical assumptions, a recent meta-analysis provides evidence that neither culture, nor gender, influences the association between dyadic coping and relationship satisfaction, at least based on their samples of couples living in North America and West Europe. Thus, it is an open questions whether the theoretical assumptions of cultural influences are false or whether cultural influences on couple behavior just occur in cultures outside of the Western world. Method: In order to examine the cultural influence, using a sample of married individuals (N = 7,973) from 35 nations, we used multilevel modeling to test whether the positive association between dyadic coping and relationship satisfaction varies across nations and whether gender might moderate the association. Results: Results reveal that the association between dyadic coping and relationship satisfaction varies between nations. In addition, results show that in some nations the association is higher for men and in other nations it is higher for women. Conclusions: Cultural and gender differences across the globe influence how couples’ coping behavior affects relationship outcomes. This crucial finding indicates that couple relationship education programs and interventions need to be culturally adapted, as skill trainings such as dyadic coping lead to differential effects on relationship satisfaction based on the culture in which couples live.