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Influence of Environmental and Microclimate Factors on the Coffee Beans Quality (C. canephora): Correlation between Chemical Analysis and Stable Free Radicals

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Agricultural Sciences 2018年第9期9卷 1173-1187页

作者： AndréLuíz Alves marcio solino pessoa Paulo Eduardo Narcizo de Souza Fábio Luís Partelli Paulo Sérgio Moscon Edson Correa da Silva André Oliveira Guimaraes Eduardo Perini Muniz Patrícia Fontes Pinheiro Flávio Meira Borém Paulo César Morais Departamento de Ciências Naturais Universidade Federal do Espírito SantoCentro Universitário Norte do Espírito SantoSao MateusBrazil Universidade de Brasília Instituto de FísicaNúcleo de Física AplicadaBrasília DFBrazil Laboratório de Ciências Físicas Centro de Ciências e TecnologiaUniversidade Estadual Norte FluminenseCampos dos GoytacasesBrazil Departamento de Química e Física Universidade Federal do Espírito SantoAlto UniversitárioAlegreBrazil Departamento de Engenharia Universidade Federal de LavrasLavrasBrazil School of Chemistry and Chemical Engineering Anhui UniversityHefeiChina

The present study reports a physicochemical comparison of shade-grown and sun-grown coffee beans, under unripe, rip and roasted-ripe conditions, using electrical conductivity measurements, electron paramagnetic resonance (EPR), infrared spectroscopy (FTIR), and high performance liquid chromatography (HPLC). Moreover, the assessed physicochemical parameters were compared with organoleptic evaluations based on the Coffee Quality Institute protocol. The values found for electrical conductivity, leached potassium, and stable free radicals were respectively 29%, 31%, and 350% higher for shade-grown coffee beans, whereas polyphenol oxidase enzymatic activity was 23% lower. By contrast, FTIR and HPLC measurements identified higher chlorogenic acid and lipid contents in sun-grown coffee beans. Importantly, the sensorial grade attributed to roasted-ripe grains was 12% higher for sun-grown coffee. Our findings suggest that shade-grown coffee beans have undergone microorganismal activity and undesired fermentation during cultivation, which resulted in lower coffee quality. A correlation between a set of selected physicochemical properties and organoleptic properties was robustly established and could be used in the development of future coffee bean quality control protocols.

关键词： Sun-Grown Coffee Shade-Grown Coffee Fermentation EPR FTIR HPLC

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Unit Root Analysis of Traffic Time Series in Toll Highways

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Journal of Civil Engineering and Architecture 2012年第12期6卷 1641-1647页

作者： Antonio Sanchez solino Antonio L. Lara Galera Construction Department Madrid Polytechnic University Madrid 28040 Spain

Concession contracts in highways often include some kind of clauses （for example, a minimum traffic guarantee） that allow for better management of the business risks. The value of these clauses may be important and should be added to the total value of the concession. However, in these cases, traditional valuation techniques, like the NPV （net present value） of the project, are insufficient. An alternative methodology for the valuation of highway concession is one based on the real options approach. This methodology is generally built on the assumption of the evolution of traffic volume as a GBM （geometric Brownian motion）, which is the hypothesis analyzed in this paper. First, a description of the methodology used for the analysis of the existence of unit roots （i.e., the hypothesis of non-stationarity） is provided. The Dickey-Fuller approach has been used, which is the most common test for this kind of analysis. Then this methodology is applied to perform a statistical analysis of traffic series in Spanish toll highways. For this purpose, data on the AADT （annual average daily traffic） on a set of highways have been used. The period of analysis is around thirty years in most cases. The main outcome of the research is that the hypothesis that traffic volume follows a GBM process in Spanish toll highways cannot be rejected. This result is robust, and therefore it can be used as a starting point for the application of the real options theory to assess toll highway concessions.

关键词： Real options unit root analysis investment highway concession traffic.

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