31 research outputs found

    Room-temperature polariton lasing in quantum heterostructure nanocavities

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    Controlling light-matter interactions in solid-state systems has motivated intense research to produce bosonic quasi-particles known as exciton-polaritons, which requires strong coupling between excitons and cavity photons. Ultra-low threshold coherent light emitters can be achieved through lasing from exciton-polariton condensates, but this generally requires sophisticated device structures and cryogenic temperatures. Polaritonic nanolasers operating at room temperature lie on the crucial path of related research, not only for the exploration of polariton physics at the nanoscale but also for potential applications in quantum information systems, all-optical logic gates, and ultra-low threshold lasers. However, at present, progress toward room-temperature polariton nanolasers has been limited by the thermal instability of excitons and the inherently low quality factors of nanocavities. Here, we demonstrate room-temperature polaritonic nanolasers by designing wide-gap semiconductor heterostructure nanocavities to produce thermally stable excitons coupled with nanocavity photons. The resulting mixed states of exciton-polaritons with Rabi frequencies of approximately 370 meV enable persistent polariton lasing up to room temperature, facilitating the realization of miniaturized and integrated polariton systems

    Cancer is a Preventable Disease that Requires Major Lifestyle Changes

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    This year, more than 1 million Americans and more than 10 million people worldwide are expected to be diagnosed with cancer, a disease commonly believed to be preventable. Only 5–10% of all cancer cases can be attributed to genetic defects, whereas the remaining 90–95% have their roots in the environment and lifestyle. The lifestyle factors include cigarette smoking, diet (fried foods, red meat), alcohol, sun exposure, environmental pollutants, infections, stress, obesity, and physical inactivity. The evidence indicates that of all cancer-related deaths, almost 25–30% are due to tobacco, as many as 30–35% are linked to diet, about 15–20% are due to infections, and the remaining percentage are due to other factors like radiation, stress, physical activity, environmental pollutants etc. Therefore, cancer prevention requires smoking cessation, increased ingestion of fruits and vegetables, moderate use of alcohol, caloric restriction, exercise, avoidance of direct exposure to sunlight, minimal meat consumption, use of whole grains, use of vaccinations, and regular check-ups. In this review, we present evidence that inflammation is the link between the agents/factors that cause cancer and the agents that prevent it. In addition, we provide evidence that cancer is a preventable disease that requires major lifestyle changes

    Roles of Cytokines in the Temporal Changes of Microglial Membrane Currents and Neuronal Excitability and Synaptic Efficacy in ATP-Induced Cortical Injury Model

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    Cytokines are important neuroinflammatory modulators in neurodegenerative brain disorders including traumatic brain injury (TBI) and stroke. However, their temporal effects on the physiological properties of microglia and neurons during the recovery period have been unclear. Here, using an ATP-induced cortical injury model, we characterized selective effects of ATP injection compared to needle-control. In the damaged region, the fluorescent intensity of CX3CR1-GFP (+) cells, as well as the cell density, was increased and the maturation of newborn BrdU (+) cells continued until 28 day-post-injection (dpi) of ATP. The excitability and synaptic E/I balance of neurons and the inward and outward membrane currents of microglia were increased at 3 dpi, when expressions of tumor necrosis factor (TNF)-α/interleukin (IL)-1β and IL-10/IL-4 were also enhanced. These changes of both cells at 3 dpi were mostly decayed at 7 dpi and were suppressed by any of IL-10, IL-4, suramin (P2 receptor inhibitor) and 4-AP (K+ channel blocker). Acute ATP application alone induced only small effects from both naïve neurons and microglial cells in brain slice. However, TNF-α alone effectively increased the excitability of naïve neurons, which was blocked by suramin or 4-AP. TNF-α and IL-1β increased and decreased membrane currents of naïve microglia, respectively. Our results suggest that ATP and TNF-α dominantly induce the physiological activities of 3 dpi neurons and microglia, and IL-10 effectively suppresses such changes of both activated cells in K+ channel- and P2 receptor-dependent manner, while IL-4 suppresses neurons preferentially

    Data from: Karyotype and genome size variation in genus Ajuga L. (Ajugoideae–Lamiaceae)

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    Chromosome number changes and karyotype evolution play an important role in plant genome diversification and eventually in speciation. The genus Ajuga L. (Lamiaceae) has approximately 50 species distributed in temperate to subtropical regions. Four of these species are currently recognized in Korea (A. decumbens Thunb., A. multiflora Bunge, A. nipponensis Makino and A. spectabilis Nakai). Understanding the karyotype evolution in Ajuga has been hampered by the small size of their chromosomes and symmetrical karyotypes. Here we used classic Feulgen staining to establish chromosome numbers and construct karyotypes of the four species of Ajuga recognized in Korea and flow cytometry was used to study their variation in genome. The chromosome number of all investigated plants was 2n = 32. Still, the 2C DNA content ranged from 2.18 pg (A. decumbens) to 4.53 pg (A. multiflora). While the chromosome numbers were the same for all investigated species, the genome size variation could potentially be used as a taxonomic marker

    Textile-fiber-embedded multiluminescent devices: A new approach to soft display systems

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    In the recent remarkable advances in soft electronic systems, light-emitting functions play a prominent role. In particular, polymer composite systems with embedded luminescent particles have attracted considerable attention as a luminescent component owing to their flexibility and simple fabrication. However, most flexible composite-based electroluminescent (EL) devices have coplanar structures, requiring mechanically compliant electrodes with high transmittance, durability, and stable electrical conductivity. This is a limitation for systems designed for providing superior flexible characteristics without loss of luminescence. Here, we introduce a novel EL device architecture—a durable/flexible textile-fiber-embedded polydimethylsiloxane and zinc sulfide (PDMS + ZnS) composite, driven by an in-plane electric field, which eliminates the requirement for high transmittance. On applying an AC voltage, light is radially emitted from the ZnS particles surrounding the fibers, originating from the radially distributed electric/optical fields; the rolling and stretching flexibilities are maintained during this process. The device also exhibits strong EL intensities in a thick emitting layer—a parameter on which EL and mechanoluminescent (ML) intensities in coplanar structures are dependent. This is because the electric field is applied between in-plane fibers. Using this smart design, simultaneously high EL and ML intensities can be simply achieved by embedding fibers in strong ML-emitting PDMS + ZnS. We also present a patterned device controlled by different fiber embedding depths, utilizing the vertical and in-plane electric fields. This application may provide a basis for the development of emerging soft display systems that require high luminescence as well as flexibility in the light-emitting components. © 2019 Elsevier Ltd1

    Karyotype characters in the genus Ajuga L. (Chromosome size measurement)

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    Karyotype characters and chromosome numbers in the genus Ajuga L

    Operation algorithm of PV/BESS application considering demand response uncertainty in an independent microgrid system

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    Various renewable energy sources, such as wind and solar photovoltaic (PV) cells, are now being used in power systems. Meanwhile, few new steam power plants and transmission lines are being constructed because of the environmental problems they cause. As an alternative, small-scale independent power systems with energy-storage systems such as microgrids are increasing. In a small microgrid system that is vulnerable to frequency variation, coordinating an optimized scheduling between the energy-storage system and renewable energy generation is important. However, considering the uncertainty of weather forecasting and uneven load patterns, several cases should be considered. In this paper, the operation algorithm of a stable PV/BESS system is proposed. This system contributes helps decide the output battery to design battery capacity as a contingency for unexpected situations in a microgrid system

    Energy values and protein digestibility of soybean milk by-product in pigs based on in vitro assays

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    Background: Soybean milk by-product (SMBP) is a potential alternative feed ingredient in swine diets due to its high protein content. However, information on energy and nutritional values of SMBP used as swine feed ingredient is limited. Objective: To estimate energy values and protein digestibility of SMBP in pigs based on in vitro assays. Methods: Four SMBP samples were obtained from 3 soybean milk-producing facilities. In vitro total tract disappearance (IVTTD) and in vitro ileal disappearance (IVID) of dry matter (DM) in the SMBP samples were determined. In vitro ileal disappearance of crude protein was determined by analyzing crude protein content in undigested residues after determining IVID of DM. Digestible and metabolizable energy of SMBP were estimated using gross energy, IVTTD of DM, and prediction equations. Results: Sample 4 had greater IVTTD of DM than that of sample 3 (97.7 vs. 94.4%, p<0.05), whereas IVID of DM in sample 4 was lower compared with sample 1 (53.5 vs. 65.0%, p<0.05). In vitro ileal disappearance of crude protein in sample 2 was greater than that in sample 1 and 3 (92.6 vs. 90.6 and 90.1%; p<0.05). The estimated metabolizable energy of SMBP ranged from 4,311 to 4,619 kcal/kg as-is basis and the value of sample 3 was the least (p<0.05) among SMBP samples. Conclusion: Energy values and protein digestibility should be determined before using SMBP in swine diets.Antecedentes: O subproduto do leite de soja (SMBP) é um potencial ingrediente alternativo na dieta de suínos, considerando seu alto teor de proteínas. No entanto, as informações sobre os valores energéticos e nutricionais do SMBP usado como ingrediente alimentar para suínos são limitadas. Objetivo: Estimar valores energéticos e digestibilidade protéica do SMBP em suínos com base em ensaios in vitro. Métodos: Foram obtidas quatro amostras de SMBP de três instalações produtores de leite de soja. Foram determinados o desaparecimento total do trato in vitro (IVTTD) e o desaparecimento ileal in vitro (IVID) da matéria seca (DM) nas amostras de SMBP. O desaparecimento ileal in vitro da proteína bruta foi determinado pela análise do conteúdo de proteína bruta em resíduos não digeridos após a determinação da IVID do DM. A energia digerível e metabolizável do SMBP foi estimada usando energia bruta, IVTTD do DM e equações de predição. Resultados: a amostra 4 apresentou maior IVTTD de DM do que a amostra 3 (97,7 vs. 94,4%, p<0,05) enquanto a IVID do DM na amostra 4 foi menor em comparação com a amostra 1 (53,5 vs. 65,0%, p<0,05). O desaparecimento ileal in vitro da proteína bruta na amostra 2 foi superior ao da amostra 1 e 3 (92,6 vs. 90,6 e 90,1%; p<0,05). A energia metabolizável estimada do SMBP variou de 4.311 a 4.619 kcal/kg no estado em que se encontra e o valor da amostra 3 foi o menor (p<0,05) entre as amostras do SMBP. Conclusão: os valores energéticos e a digestibilidade das proteínas devem ser determinados antes do uso do SMBP nas dietas suínas.Antecedentes: El subproducto de la leche de soja (SMBP) es un ingrediente alimenticio alternativo con uso potencial en dietas porcinas dado su alto contenido de proteína. Sin embargo, la información sobre sus valores energéticos y nutricionales para alimentación de cerdos es muy limitada. Objetivo: Estimar los valores de energía y la digestibilidad de la proteína del SMBP en cerdos con base en ensayos in vitro. Métodos: Se obtuvieron cuatro muestras de SMBP de tres empresas productoras de leche de soja. Se determinaron la desaparición de tracto total in vitro (IVTTD) y la desaparición ileal in vitro (IVID) de la materia seca (DM) en las muestras de SMBP. La desaparición ileal in vitro de proteína cruda se determinó analizando el contenido de proteína cruda en residuos no digeridos después de determinar la IVID de la DM. La energía digestible y metabolizable de SMBP se estimó utilizando la energía bruta, IVTTD de la DM y ecuaciones de predicción. Resultados: La muestra 4 tuvo una mayor IVTTD de la DM que la muestra 3 (97,7 vs. 94,4%, p<0,05), mientras que la IVID de la DM en la muestra 4 fue menor en comparación con la muestra 1 (53,5 vs. 65,0%, p<0,05). La desaparición ileal in vitro de la proteína cruda en la muestra 2 fue mayor que la de las muestras 1 y 3 (92,6 vs. 90,6 y 90,1%; p<0,05). La energía metabolizable estimada de SMBP varió de 4.311 a 4.619 kcal/kg (en base húmeda) y el valor de la muestra 3 fue el menor (p<0.05) entre las muestras de SMBP. Conclusión: Los valores de energía y la digestibilidad de la proteína deben determinarse antes de usar el SMBP en dietas porcinas

    Periodically Diameter-Modulated Semiconductor Nanowires for Enhanced Optical Absorption

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    A novel approach to enhancing optical absorption was reported by modulating the diameters of semiconducting nanowires, in which the diameter changes periodically in a sinusoidal manner along the long axis of the wire. 3D finite-difference time-domain (FDTD) simulations were used to calculate the optical properties of the diameter-modulated nanowires and compared the results with those for simple cylindrical nanowires and planar bulk silicon. The diameter-modulated silicon nanowires were modeled using a sinusoidal radial function with a period of 565 nm and modulated diameters of 495 and 380 nm at the convex and concave points, respectively, whereas the simple cylindrical silicon nanowire had a diameter of 410 nm. The optical absorption was calculated by measuring the power absorbed by the same volume of silicon over a propagation distance of 283 nm from the top surface, corresponding to the half-period of the diameter modulation. The results show that the optical absorption efficiency is highly enhanced with decreasing the mean diameter, and also increased with decreasing the modulation period, where the diameter difference is 115 nm from convex to concave points. On the other hand, the absorption effi ciency is not sensitive to the nanowire length of a few μm scale due to short propagation lengths less than 2 μm.1
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