326 research outputs found

    Furfural Production in a Spinning Disc Reactor

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    Incandescent temporal metamaterials

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    Regarded as a promising alternative to spatially shaping matter, time-varying media can be seized to control and manipulate wave phenomena, including thermal radiation. Here, based upon the framework of macroscopic quantum electrodynamics, we elaborate a comprehensive quantum theoretical formulation that lies the basis for investigating thermal emission effects in time-modulated media. Our theory unveils new physics brought about by time-varying media: nontrivial correlations between thermal fluctuating currents at different frequencies and positions, thermal radiation overcoming the black-body spectrum, and quantum vacuum amplification effects at finite temperature. We illustrate how these features lead to striking phenomena and novel thermal emitters, specifically, showing that the time-modulation releases strong field fluctuations confined within epsilon-near-zero (ENZ) bodies, and that, in turn, it enables a narrowband (partially coherent) emission spanning the whole range of wavevectors, from near to far-field regimes.Comment: Main text (11 pages, 5 figures) + Supplementary Information (32 pages

    Technology shocks and monetary policy : assessing the Fed's performance

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    El estudio tiene un doble proposito: caracterizar las respuestas sistematicas de la Reserva Federal americana ante perturbaciones tecnologicas y sus efectos sobre la produccion, las horas trabajadas y la tasa de inflaciony evaluar si tales respuestas pueden explicarse a traves de reglas de comportamiento alternativas para la Reserva Federal, en el marco de un modelo de ciclos economicos con precios rigidos. Los resultados son los siguientes: 1) se encuentran diferencias significativas por subperiodos en las respuestas de la economia ante perturbaciones tecnologicas. 2) las respuestas de la Reserva Federal durante el periodo Volcker-Greenspan son consistentes con las asociadas a una regla optima. 3) durante el periodo anterior a Volcker, la Reserva Federal respondio excesivamente al ouput generando una excesiva volatilidad en la tasa de inflacion. La evidencia es consecuente con resultados recientes de la literatura que enfatizan la mejora en la ejecucion de la politica monetaria de la Reserva Federal. (jg) (ad

    Inflation differentials in EMU : the Spanish case

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    In this paper we present some descriptive evidence and simulation exercises with both an estimated backward looking model and a calibrated general equilibrium forward looking model that allow some light to be shed on the determinants and macroeconomic implications of persistent inflation differentials in Spain within EMU. We show that a demand expansion biased towards consumption of non-tradable goods and real-wage rigidities -such as wage indexation clauses- are among the key determinants of diverging price developments in Spain. Moreover, we find that in those conditions the stabilising mechanism of terms of trade effects is relatively weak, although the economy undergoes lasting losses in competitiveness

    The liquidity effect in small open economy model

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    En este trabajo se presenta un modelo dinamico y estocastico de equilibrio general para caracterizar una economia pequeña y abierta bajo perfecta movilidad de capitales. El modelo incluye, de un lado, rigideces nominales en los mercados imperfectamente competitivos de bienes y trabajoy de otro, rigideces reales a traves de costes de ajuste del capital de las empresas. El modelo explica algunas caracteristicas ciclicas nominales y reales de las economias europeas, y genera respuestas positivas del producto ante perturbaciones monetarias. Sin embargo, el mecanismo de transmision de este tipo de shocks es distinto del analisis keynesiano convencional. De hecho, es necesaria una muy importante inercia de precios para garantizar una respuesta positiva de los saldos reales tras un shock persistente de caracter monetario. Ademas, solo encontramos efecto liquidez, y por tanto, 'overshooting' en el tipo de cambio nominal cuando el grado de sustitucion intertemporal del consumo es muy elevado. (ja) (ad

    Suppressed-scattering spectral windows for radiative cooling applications

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    The scattering of light by resonant nanoparticles is a key process for enhancing the solar reflectance in daylight radiative cooling. Here, we investigate the impact of material dispersion on the scattering performance of popular nanoparticles for radiative cooling applications. We show that, due to material dispersion, nanoparticles with a qualitatively similar response at visible frequencies exhibit fundamentally different scattering properties at infrared frequencies. It is found that dispersive nanoparticles exhibit suppressed-scattering windows, allowing for selective thermal emission within a highly reflective sample. The existence of suppressed-scattering windows solely depends on material dispersion, and they appear pinned to the same wavelength even in random composite materials and periodic metasurfaces. Finally, we investigate calcium-silicate-hydrate (CSH), the main phase of concrete, as an example of a dispersive host, illustrating that the co-design of nanoparticles and host allows for tuning of the suppressed-scattering windows. Our results indicate that controlled nanoporosities would enable concrete with daylight passive radiative cooling capabilities

    First-in-human phase I/II, open-label study of the anti-OX40 agonist INCAGN01949 in patients with advanced solid tumors

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    Inmunomodulación; Linfocitos T; Microambiente tumoralImmunomodulació; Limfòcits T; Microambient tumoralImmunomodulation; T-Lymphocytes; Tumor microenvironmentBackground OX40 is a costimulatory receptor upregulated on antigen-activated T cells and constitutively expressed on regulatory T cells (Tregs). INCAGN01949, a fully human immunoglobulin G1κ anti-OX40 agonist monoclonal antibody, was designed to promote tumor-specific immunity by effector T-cell activation and Fcγ receptor-mediated Treg depletion. This first-in-human study was conducted to determine the safety, tolerability, and preliminary efficacy of INCAGN01949. Methods Phase I/II, open-label, non-randomized, dose-escalation and dose-expansion study conducted in patients with advanced or metastatic solid tumors. Patients received INCAGN01949 monotherapy (7–1400 mg) in 14-day cycles while deriving benefit. Safety measures, clinical activity, pharmacokinetics, and pharmacodynamic effects were assessed and summarized with descriptive statistics. Results Eighty-seven patients were enrolled; most common tumor types were colorectal (17.2%), ovarian (8.0%), and non-small cell lung (6.9%) cancers. Patients received a median three (range 1–9) prior therapies, including immunotherapy in 24 patients (27.6%). Maximum tolerated dose was not reached; one patient (1.1%) receiving 350 mg dose reported dose-limiting toxicity of grade 3 colitis. Treatment-related adverse events were reported in 45 patients (51.7%), with fatigue (16 (18.4%)), rash (6 (6.9%)), and diarrhea (6 (6.9%)) being most frequent. One patient (1.1%) with metastatic gallbladder cancer achieved a partial response (duration of 6.3 months), and 23 patients (26.4%) achieved stable disease (lasting >6 months in one patient). OX40 receptor occupancy was maintained over 90% among all patients receiving doses of ≥200 mg, while no treatment-emergent antidrug antibodies were detected across all dose levels. Pharmacodynamic results demonstrated that treatment with INCAGN01949 did not enhance proliferation or activation of T cells in peripheral blood or reduce circulating Tregs, and analyses of tumor biopsies did not demonstrate any consistent increase in effector T-cell infiltration or function, or decrease in infiltrating Tregs. Conclusion No safety concerns were observed with INCAGN01949 monotherapy in patients with metastatic or advanced solid tumors. However, tumor responses and pharmacodynamic effects on T cells in peripheral blood and post-therapy tumor biopsies were limited. Studies evaluating INCAGN01949 in combination with other therapies are needed to further evaluate the potential of OX40 agonism as a therapeutic approach in patients with advanced solid tumors.This study was funded by Incyte Corporation (Wilmington, USA)

    On the interaction of the North Andes plate with the Caribbean and South American plates in northwestern South America from GPS geodesy and seismic data

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    We examine the hypocentral distribution of seismicity and a series of geodetic velocity vectors obtained from Global Positioning System observations between 1994 and 2015 both offshore and mainland northwestern South America (66°W–77°W; 8°N–14°N). Our analysis, that includes a kinematic block modelling, shows that east of the Caribbean–South American–North Andes plates’ triple junction at ∼68°W; 10.7°N, right-lateral easterly oriented shear motion (∼19.6 ± 2.0 mm yr−1) between the Caribbean and South America plates is split along two easterly striking, right-lateral strike-slip subparallel fault zones: the San Sebastián fault that runs off-shore the Venezuelan coast and slips about 17.0±0.5mm yr−1 and the La Victoria fault, located on-shore to the south, which is accumulating strain equivalent to 2.6 ± 0.4 mm yr−1.West of the triple junction, relative right-lateral motion between the Caribbean and South American plates is mostly divided between the Morrocoy and Boconó fault systems that strike northwest and southwest from the triple junction, respectively, and bound the intervening North Andes plate that shows an easterly oriented geodetic slip of 15.0 ± 1.0 mm yr−1 relative to the South American plate. Slip on the Morrocoy fault is right-lateral and transtensional. Motion across the Boconó fault is also right-lateral but instead transpressional, divided between ∼9 and 11 mm yr−1 of right-slip on the Bocon´o fault and 2–5 mm yr−1 of convergence across adjacent and subparallel thrust faults. Farther west of the triple junction, ∼800 km away in northern Colombia, the Caribbean plate subducts to the southeast beneath the North Andes plate at a geodetically estimated rate of ∼5–7 mm yr−1

    Radiative Cooling Properties of Portlandite and Tobermorite: Two Cementitious Minerals of Great Relevance in Concrete Science and Technology

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    Although concrete and cement-based materials are the most engineered materials employed by mankind, their potential for use in daytime radiative cooling applications has yet to be fully explored. Due to its complex structure, which is composed of multiple phases and textural details, fine-tuning of concrete is impossible without first analyzing its most important ingredients. Here, the radiative cooling properties of Portlandite (Ca(OH)2) and Tobermorite (Ca5Si6O16(OH)2·4H2O) are studied due to their crucial relevance in cement and concrete science and technology. Our findings demonstrate that, in contrast to concrete (which is a strong infrared emitter but a poor sun reflector), both Portlandite and Tobermorite exhibit good radiative cooling capabilities. These results provide solid evidence that, with the correct optimization of composition and porosity, concrete can be transformed into a material suitable for daytime radiative cooling
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