THE NORTHEAST AND INTERREGIONAL COMPETITION FOR BROILERS

An interregional model which minimizes production and transportation costs for broilers was developed and tested. Ten production and 22 consumption regions were defined. The results indicate that current flow patterns are relatively efficient given the existing production capacities. As demand increases the increased production will tend to be in the Southwest (Texas) and to a lesser extent in the Southeast (North Carolina). Shadow prices indicate that in the longer run production in the Northeast will continue to decline in relative terms and perhaps in absolute terms.Resource /Energy Economics and Policy,

Removal of sulfamethoxazole and sulfapyridine by carbon nanotubes in fixed-bed columns

Sulfamethoxazole (SMX) and sulfapyridine (SPY), two representative sulfonamide antibiotics, have gained increasing attention because of the ecological risks these substances pose to plants, animals, and humans. This work systematically investigated the removal of SMX and SPY by carbon nanotubes (CNTs) in fixed-bed columns under a broad range of conditions including: CNT incorporation method, solution pH, bed depth, adsorbent dosage, adsorbate initial concentration, and flow rate. Fixed-bed experiments showed that pH is a key factor that affects the adsorption capacity of antibiotics to CNTs. The Bed Depth Service Time model describes well the relationship between service time and bed depth and can be used to design appropriate column parameters. During fixed-bed regeneration, small amounts of SMX (3%) and SPY (9%) were irreversibly bonded to the CNT/sand porous media, thus reducing the column capacity for subsequent reuse from 67.9 to 50.4 mg g−1 for SMX and from 91.9 to 72.9 mg g−1 for SPY. The reduced column capacity resulted from the decrease in available adsorption sites and resulting repulsion (i.e., blocking) of incoming antibiotics from those previously adsorbed. Findings from this study demonstrate that fixed-bed columns packed with CNTs can be efficiently used and regenerated to remove antibiotics from water

Estudio preliminar sobre el efecto del ultrasonido en las propiedades fisicoquímicas del vino tinto

Ultrasound is regarded as a potential alternative method for improving the quality of some wines. This study was initiated with the objective of evaluating the effects of ultrasound on some important physicochemical properties of red wine such as chromatic characteristics (CC), electrical conductivity (EC), pH, titratable acidity (TA), total phenolic compounds (TPCs) and DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging activity (DFRSA). The operational parameters assessed were ultrasound power, ultrasound frequency, exposure time and bath temperature. Results illustrated that there were significant changes in CC, EC and TPC while pH and TA hardly changed except for samples treated at high temperatures. DFRSA was correlated to TPC during ultrasonic treatment. Application of principal component analysis to the experimental data suggested that exposure time was the factor with the greatest ability to induce changes on wine. Results suggested that ultrasound may be applied to improve some physicochemical properties of red wine.El ultrasonido se considera uno de los métodos alternativos potenciales para mejorar la calidad de algunos vinos. Se comenzó este estudio con el objetivo de evaluar los efectos del ultrasonido en algunas de la propiedades fisicoquímicas importantes del vino tinto como son: las características cromáticas (CC), la conductividad eléctrica (EC), el pH, la acidez (TA), los compuestos fenólicos totales (TPC) y el DPPH (1,1-difenil-2-picrilhidrazil) de actividad de eliminación de radicales libres (DFRSA). Los parámetros operacionales examinados fueron: la potencia de ultrasonido, la frecuencia de ultrasonido, el tiempo de exposición y la temperatura de baño. Los resultados ilustraron la existencia de cambios significativos en CC, EC y TPC, mientras que el pH y TA prácticamente no cambiaron excepto en las muestras tratadas con altas temperaturas. DFRSA tuvo correlación con TPC durante el tratamiento con ultrasonido. La aplicación de análisis de componentes principales a los datos experimentales sugirió que el tiempo de exposición era el factor con mayor habilidad para inducir cambios en el vino. Los resultados sugirieron que el ultrasonido podría aplicarse para mejorar algunas de las propiedades fisicoquímicas del vino tinto.National Natural Science Foundation of China [No. 31101324]Natural Science Foundation of Shaanxi Province, China [No. 2015JM3097]Technology Transfer Promotion Project of Xi’an, Shaanxi Province, China [No.CXY1434(5)]Fundamental Research Funds for the Central Universities of China [Nos. GK201302039, GK201404006

Azimuthal distributions of radial momentum and velocity in relativistic heavy ion collisions

Azimuthal distributions of radial (transverse) momentum, mean radial momentum, and mean radial velocity of final state particles are suggested for relativistic heavy ion collisions. Using transport model AMPT with string melting, these distributions for Au + Au collisions at 200 GeV are presented and studied. It is demonstrated that the distribution of total radial momentum is more sensitive to the anisotropic expansion, as the anisotropies of final state particles and their associated transverse momentums are both counted in the measure. The mean radial velocity distribution is compared with the radial {\deg}ow velocity. The thermal motion contributes an isotropic constant to mean radial velocity

Impact of Cloud Ice Particle Size Uncertainty in a Climate Model and Implications for Future Satellite Missions

Ice particle size is pivotal to determining ice cloud radiative effect and precipitating rate. However, there is a lack of accurate ice particle effective radius (R_(ei)) observation on the global scale to constrain its representation in climate models. In support of future mission design, here we present a modeling assessment of the sensitivity of climate simulations to R_(ei) and quantify the impact of the proposed mission concept on reducing the uncertainty in climate sensitivity. We perturb the parameters pertaining to ice fall speed parameter and R_(ei) in radiation scheme, respectively, in National Center for Atmospheric Research CESM1 model with a slab ocean configuration. The model sensitivity experiments show that a settling velocity increase due to a larger R_(ei) results in a longwave cooling dominating over a shortwave warming, a global mean surface temperature decrease, and precipitation suppression. A similar competition between longwave and shortwave cloud forcing changes also exists when perturbing R_(ei) in the radiation scheme. Linearity generally holds for the climate response for R_(ei) related parameters. When perturbing falling snow particle size (R_(es)) in a similar way, we find much less sensitivity of climate responses. Our quadrupling CO₂ experiments with different parameter settings reveal that R_(ei) and R_(es) can account for changes in climate sensitivity significantly from +12.3% to −6.2%. By reducing the uncertainty ranges of R_(ei) and R_(es) from a factor of 2 to ±25%, a future satellite mission under design is expected to improve the climate state simulations and reduce the climate sensitivity uncertainty pertaining to ice particle size by approximately 60%. Our results highlight the importance of better observational constraints on R_(ei) by satellite missions

Impact of Cloud Ice Particle Size Uncertainty in a Climate Model and Implications for Future Satellite Missions

Ice particle size is pivotal to determining ice cloud radiative effect and precipitating rate. However, there is a lack of accurate ice particle effective radius (R_(ei)) observation on the global scale to constrain its representation in climate models. In support of future mission design, here we present a modeling assessment of the sensitivity of climate simulations to R_(ei) and quantify the impact of the proposed mission concept on reducing the uncertainty in climate sensitivity. We perturb the parameters pertaining to ice fall speed parameter and R_(ei) in radiation scheme, respectively, in National Center for Atmospheric Research CESM1 model with a slab ocean configuration. The model sensitivity experiments show that a settling velocity increase due to a larger R_(ei) results in a longwave cooling dominating over a shortwave warming, a global mean surface temperature decrease, and precipitation suppression. A similar competition between longwave and shortwave cloud forcing changes also exists when perturbing R_(ei) in the radiation scheme. Linearity generally holds for the climate response for R_(ei) related parameters. When perturbing falling snow particle size (R_(es)) in a similar way, we find much less sensitivity of climate responses. Our quadrupling CO₂ experiments with different parameter settings reveal that R_(ei) and R_(es) can account for changes in climate sensitivity significantly from +12.3% to −6.2%. By reducing the uncertainty ranges of R_(ei) and R_(es) from a factor of 2 to ±25%, a future satellite mission under design is expected to improve the climate state simulations and reduce the climate sensitivity uncertainty pertaining to ice particle size by approximately 60%. Our results highlight the importance of better observational constraints on R_(ei) by satellite missions

Organic Molecules in Low-Mass Protostellar Hot Cores: Submillimeter Imaging of IRAS 16293-2422

Arcsecond-resolution spectral observations toward the protobinary system IRAS 16293-2422 at 344 and 354 GHz were conducted using the Submillimeter Array. Complex organic molecules such as CH3OH and HCOOCH3 were detected. Together with the rich organic inventory revealed, it clearly indicates the existence of two, rather than one, compact hot molecular cores (smaller than or equal to 400 AU in radius) associated with each of the protobinary components identified by their dust continuum emission in the inner star-forming core.Comment: 11 pages, 3 figures, to be published in ApJ

Reduced European aerosol emissions suppress winter extremes over northern Eurasia

Winter extreme weather events receive major public attention due to their serious impacts, but the dominant factors regulating their interdecadal trends have not been clearly established. Here, we show that the radiative forcing due to geospatially redistributed anthropogenic aerosols mainly determined the spatial variations of winter extreme weather in the Northern Hemisphere during 1970–2005, a unique transition period for global aerosol forcing. Over this period, the local Rossby wave activity and extreme events (top 10% in wave amplitude) exhibited marked declining trends at high latitudes, mainly in northern Eurasia. The combination of long-term observational data and a state-of-the-art climate model revealed the unambiguous signature of anthropogenic aerosols on the wintertime jet stream, planetary wave activity and surface temperature variability on interdecadal timescales. In particular, warming due to aerosol reductions in Europe enhanced the meridional temperature gradient on the jet’s poleward flank and strengthened the zonal wind, resulting in significant suppression in extreme events over northern Eurasia. These results exemplify how aerosol forcing can impact large-scale extratropical atmospheric dynamics, and illustrate the importance of anthropogenic aerosols and their spatiotemporal variability in assessing the drivers of extreme weather in historical and future climate

Reduced European aerosol emissions suppress winter extremes over northern Eurasia

Winter extreme weather events receive major public attention due to their serious impacts, but the dominant factors regulating their interdecadal trends have not been clearly established. Here, we show that the radiative forcing due to geospatially redistributed anthropogenic aerosols mainly determined the spatial variations of winter extreme weather in the Northern Hemisphere during 1970–2005, a unique transition period for global aerosol forcing. Over this period, the local Rossby wave activity and extreme events (top 10% in wave amplitude) exhibited marked declining trends at high latitudes, mainly in northern Eurasia. The combination of long-term observational data and a state-of-the-art climate model revealed the unambiguous signature of anthropogenic aerosols on the wintertime jet stream, planetary wave activity and surface temperature variability on interdecadal timescales. In particular, warming due to aerosol reductions in Europe enhanced the meridional temperature gradient on the jet’s poleward flank and strengthened the zonal wind, resulting in significant suppression in extreme events over northern Eurasia. These results exemplify how aerosol forcing can impact large-scale extratropical atmospheric dynamics, and illustrate the importance of anthropogenic aerosols and their spatiotemporal variability in assessing the drivers of extreme weather in historical and future climate