3,238 research outputs found
Computing Macro-Effects and Welfare Costs of Temperature Volatility: A Structural Approach
We produce novel empirical evidence on the relevance of temperature volatility shocks for the dynamics of productivity, macroeconomic aggregates and asset prices. Using two centuries of UK temperature data, we document that the relationship between temperature volatility and the macroeconomy varies over time. First, the sign of the causality from temperature volatility to TFP growth is negative in the post-war period (i.e., 1950–2015) and positive before (i.e., 1800–1950). Second, over the pre-1950 (post-1950) period temperature volatility shocks positively (negatively) affect TFP growth. In the post-1950 period, temperature volatility shocks are also found to undermine equity valuations and other main macroeconomic aggregates. More importantly, temperature volatility shocks are priced in the cross section of returns and command a positive premium. We rationalize these findings within a production economy featuring long-run productivity and temperature volatility risk. In the model temperature volatility shocks generate non-negligible welfare costs. Such costs decrease (increase) when coupled with immediate technology adaptation (capital depreciation)
Aplicação foliar de fontes de cálcio na produção de alface sob cultivo protegido.
O objetivo deste trabalho foi avaliar a resposta de plantas de alface à suplementação foliar com carbonato de cálcio (CaCO3+) micronizado
Efeito de fontes de cálcio na firmeza do tomate.
O objetivo deste trabalho foi avaliar a firmeza do tomate em função da pulverização com fontes de cálcio. O experimento foi conduzido em casa de vegetação no período de janeiro a maio de 2011. O delineamento experimental utilizado foi blocos casualizados com quatro repetições e sete tratamentos (pulverização com fontes de Ca+ solúveis ou dispersíveis em água). Foi avaliada a firmeza de frutos em duas épocas de colheita. Observou-se que os tratamentos avaliados não influenciaram a firmeza do tomate
Mechanisms of 4-phenylazophenol elimination in micro- And nano-ZVI assisted-Fenton systems
The 4-phenylazophenol (4-PAP), was treated with two different sources of metallic iron (ZVI): commercial micrometric powder (pZVI) and nanoparticles synthetized by the borohydride reduction method (nZVI). 4-PAP degradation was studied both in the absence and in the presence of H2O2 at different pHs. The degradation products of 4-PAP in each treatment were followed by LC-MS and CG-MS. Results showed that, in the absence of H2O2, the azo bond reduction of 4-PAP with the formation of amines was the main mechanism involved for both ZVI sources and nZVI exhibited a faster substrate removal than pZVI. In the presence of H2O2, an additional mechanism involving the oxidation mediated by hydroxyl radicals takes place. For pZVI, the addition of H2O2 produced a complete inhibition of the reduction pathway, being the oxidation the main degradation mechanism. In the case of nZVI, the system behavior showed an important dependence on the working pH. At pH 3.00, oxidative transformation pathways prevailed, whereas at pH 5.00 an almost negligible degradation -mainly driven by 4-PAP reduction- was observed. The assessment of the involved reaction mechanisms under different conditions allows the selection of the most suitable source for a specific treatment.Fil: Donadelli, Jorge Andrés. YPF - Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Caram, Bruno Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Kalaboka, Maria. University of Ioannina; GreciaFil: Kapsi, Margarita. University of Ioannina; GreciaFil: Sakkas, Vasilios A.. University of Ioannina; GreciaFil: Carlos, Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Garcia Einschlag, Fernando Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentin
Geografie di oggi. Metodi e strategie tra ricerca e didattica
Questo volume è l’esito del confronto e delle riflessioni sviluppate durante
il II Workshop “AIIG Giovani” organizzato a Roma nell’aprile del 2013.
Nasce da un desiderio, quello di presentare l’importanza della combinazione
tra metodi d’indagine tradizionali e nuovi per costruire sapere geografico,
e da una passione, sostenuta dall’intreccio di relazioni umane che si
evolvono nel tempo.
Per chiarire quale possa essere il contributo della geografia alla comprensione
del mondo contemporaneo, sempre più complesso, gli autori presentano
le principali metodologie geografiche in quattro sezioni: “Territori della
tecnologia”, “Identità, spazi, luoghi”, “Nodi della rete” e “Approcci sperimentali
nella scuola che cambia”.
Emerge dal lavoro un quadro multifocale che rispecchia la poliedricità e
la trasversalità della geografia contemporanea, ancorato al comune bisogno
di sviluppare strumenti interpretativi e d’azione. Ci si muove nell’ambito
di una geografia critica e della complessità in grado di fornire ai cittadini
globali differenti strumenti di interpretazione e comprensione del mondo,
nuove metafore a partire dalle quali costruire e sperimentare forme alternative
di cittadinanza consapevole ed attiva. Qui la geografia ritrova lo slancio
di una disciplina fertile capace non solo di descrivere la Terra, ma anche di
immaginare e creare nuovi mondi possibili. L’approdo naturale di questo
percorso è la realtà scolastica dove è possibile sperimentare nuove forme
di sapere e azione per rispondere alla sfida educativa contemporanea
Cuantificación, frecuencia de división celular y producción de bacterias planctónicas en el Embalse del Río III - variables relacionadas
During a whole year (1987-1988), monthly variations of biomass, frequency of dividing cells and production of bacterioplankton were studied in the Embalse del Río III Reservoir (Córdoba, Argentina). Algal biomass and production were measuredsimultaneously. A significant relationship between bacterial and algal production was observed, being temperature an important regulator factor. Bacterial biomass valúes did not correlate with their production rates. Low valúes and variability in the frequency of dividing cells were probably due to methodological difficulties for detecting división in very little cells. These data suggest that the frequency of dividing cells is not a reliableindicator of total active bacteria. Annually bacteria cycled nearly 60% of organic matter produced by phytoplankton in the water column.During a whole year (1987-1988), monthly variations of biomass, frequency of dividing cells and production of bacterioplankton were studied in the Embalse del Río III Reservoir (Córdoba, Argentina). Algal biomass and production were measuredsimultaneously. A significant relationship between bacterial and algal production was observed, being temperature an important regulator factor. Bacterial biomass valúes did not correlate with their production rates. Low valúes and variability in the frequency of dividing cells were probably due to methodological difficulties for detecting división in very little cells. These data suggest that the frequency of dividing cells is not a reliableindicator of total active bacteria. Annually bacteria cycled nearly 60% of organic matter produced by phytoplankton in the water column
Differences in measures of the fiscal multiplier and the reduced-form vector autoregression
The literature has recently asked whether the effects of fiscal policy vary with the state of the economy (Christiano, Eichenbaum, and Rebelo 2011; Rendahl 2014; Auerbach and Gorodnichenko 2012). We study this question in the context of vector autoregression (VAR) estimation. We show formally that, if (asymptotically) the parameters of the reduced-form VAR differ, then the dynamic effects of fiscal policy differ as well, generically and for any set of identification assumptions. Thus, in theory, the econometrician can detect these differences (either across time or space) generically just by relying on reduced-form VAR estimation
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