Population trends and urbanization. Simulating density effects using a local regression approach

7siopenDensity-dependent population growth regulates long-term urban expansion and shapes distinctive socioeconomic trends. Despite a marked heterogeneity in the spatial distribution of the resident population, Mediterranean European countries are considered more homogeneous than countries in other European regions as far as settlement structure and processes of metropolitan growth are concerned. However, rising socioeconomic inequalities among Southern European regions reflect latent demographic and territorial transformations that require further investigation. An integrated assessment of the spatio-temporal distribution of resident populations in more than 1000 municipalities (1961-2011) was carried out in this study to characterize density-dependent processes of metropolitan growth in Greece. Using geographically weighted regressions, the results of our study identified distinctive local relationships between population density and growth rates over time. Our results demonstrate that demographic growth rates were non-linearly correlated with other variables, such as population density, with positive and negative impacts during the first (1961-1971) and the last (2001-2011) observation decade, respectively. These findings outline a progressive shift over time from density-dependent processes of population growth, reflecting a rapid development of large metropolitan regions (Athens, Thessaloniki) in the 1960s, to density-dependent processes more evident in medium-sized cities and accessible rural regions in the 2000s. Density-independent processes of population growth have been detected in the intermediate study period (1971-2001). This work finally discusses how a long-term analysis of demographic growth, testing for density-dependent mechanisms, may clarify the intrinsic role of population concentration and dispersion in different phases of the metropolitan cycle in Mediterranean Europe.openPolinesi G.; Recchioni M.C.; Turco R.; Salvati L.; Rontos K.; Rodrigo-Comino J.; Benassi F.Polinesi, G.; Recchioni, M. C.; Turco, R.; Salvati, L.; Rontos, K.; Rodrigo-Comino, J.; Benassi, F

Advances in High-Energy-Resolution CdZnTe Linear Array Pixel Detectors with Fast and Low Noise Readout Electronics

Radiation detectors based on Cadmium Zinc Telluride (CZT) compounds are becoming popular solutions thanks to their high detection efficiency, room temperature operation, and to their reliability in compact detection systems for medical, astrophysical, or industrial applications. However, despite a huge effort to improve the technological process, CZT detectors’ full potential has not been completely exploited when both high spatial and energy resolution are required by the application, especially at low energies (<10 keV), limiting their application in energy-resolved photon counting (ERPC) systems. This gap can also be attributed to the lack of dedicated front-end electronics which can bring out the best in terms of detector spectroscopic performances. In this work, we present the latest results achieved in terms of energy resolution using SIRIO, a fast low-noise charge sensitive amplifier, and a linear-array pixel detector, based on boron oxide encapsulated vertical Bridgman-grown B-VB CZT crystals. The detector features a 0.25-mm pitch, a 1-mm thickness and is operated at a −700-V bias voltage. An equivalent noise charge of 39.2 el. r.m.s. (corresponding to 412 eV FWHM) was measured on the test pulser at 32 ns peaking time, leading to a raw resolution of 1.3% (782 eV FWHM) on the 59 keV line at room temperature (+20 °C) using an uncollimated 241Am, largely improving the current state of the art for CZT-based detection systems at such short peaking times, and achieving an optimum resolution of 0.97% (576 eV FWHM) at 1 µs peaking time. The measured energy resolution at the 122 keV line and with 1 µs peaking time of a 57Co raw uncollimated spectrum is 0.96% (1.17 keV). These activities are in the framework of an Italian collaboration on the development of energy-resolved X-ray scanners for material recycling, medical applications, and non-destructive testing in the food industry

Analysis of Diterpens in Green and Roasted Coffee of Coffea arabica Cultivars Growing in the Same Edapho-Climatic Conditions.

Lipids are important components of coffee beverage flavor and aroma. Coffee oil is rich in diterpens of the kaurane family, mainly cafestol (C20H28O3) and kahweol (C20H26O3), which have increasingly received attention in recent years due to their physiological effects in human health. However, few studies have been conducted on the effects of the genetic variability for those lipids in Coffea arabica. In this work we initiate the characterization of cafestol and kahweol in different cultivars of Coffea arabica, growing in the same edaphoclimatic conditions. Mature coffee fruits from cultivars Catuaí, Icatu and three Catucaí derived the cultivars IPR 100, IPR 102 and IPR 106. They were harvested at the Agricultural Field Station of the Coop COCARI, Mandaguari, Paraná, Brazil, from May to July 2009. Although the time of harvesting was according to the maturation of each cultivar, harvesting and post-harvesting conditions were the same for all cultivars. The five samples were subjected to medium roasting for 8 to 11 minutes at 200-210 °C, until the degree of roasting light/media (L* around 28). The extraction of diterpens was carried out in green or roasted coffee by direct saponification with KOH, extraction with terc-butyl methyl ether, and clean up with water. A reverse-phase HPLC column with isocratic elution with acetonitrile/water (55/45 v/v) was used for detection and quantification of kahweol at 290 nm and cafestol at 220 nm. In green beans, the level of kahweol was higher than cafestol, for all three IPR cultivars. Meanwhile, the inverse was observed for green beans cultivars Catuaí and Icatu, where cafestol levels were higher than kahweol. The higher levels of kahweol in relation to cafestol were again observed in roasted coffee of the three IPR cultivars. In cultivars Icatu the values for kahweol and cafestol were similar (635 and 683 mg/100 g, respectively). The highest levels of kahweol were observed in cultivar IPR 106 (1096 mg/100 g). The cultivar IPR 102 showed the highest level of cafestol (394 mg/100g). Association of this data with gene expression profile can be useful to find genes involved in cafestol and kahweol metabolism as well as to develop molecular markers for diterpens in coffee

Advances in High-Energy-Resolution CdZnTe Linear Array Pixel Detectors with Fast and Low Noise Readout Electronics

: Radiation detectors based on Cadmium Zinc Telluride (CZT) compounds are becoming popular solutions thanks to their high detection efficiency, room temperature operation, and to their reliability in compact detection systems for medical, astrophysical, or industrial applications. However, despite a huge effort to improve the technological process, CZT detectors' full potential has not been completely exploited when both high spatial and energy resolution are required by the application, especially at low energies (<10 keV), limiting their application in energy-resolved photon counting (ERPC) systems. This gap can also be attributed to the lack of dedicated front-end electronics which can bring out the best in terms of detector spectroscopic performances. In this work, we present the latest results achieved in terms of energy resolution using SIRIO, a fast low-noise charge sensitive amplifier, and a linear-array pixel detector, based on boron oxide encapsulated vertical Bridgman-grown B-VB CZT crystals. The detector features a 0.25-mm pitch, a 1-mm thickness and is operated at a -700-V bias voltage. An equivalent noise charge of 39.2 el. r.m.s. (corresponding to 412 eV FWHM) was measured on the test pulser at 32 ns peaking time, leading to a raw resolution of 1.3% (782 eV FWHM) on the 59 keV line at room temperature (+20 °C) using an uncollimated 241Am, largely improving the current state of the art for CZT-based detection systems at such short peaking times, and achieving an optimum resolution of 0.97% (576 eV FWHM) at 1 µs peaking time. The measured energy resolution at the 122 keV line and with 1 µs peaking time of a 57Co raw uncollimated spectrum is 0.96% (1.17 keV). These activities are in the framework of an Italian collaboration on the development of energy-resolved X-ray scanners for material recycling, medical applications, and non-destructive testing in the food industry

El Niño teleconnection to the Euro-Mediterranean late-winter: the role of extratropical Pacific modulation

El Niño Southern Oscillation (ENSO) represents the major driver of interannual climate variability at global scale. Observational and model-based studies have fostered a long-standing debate on the shape and intensity of the ENSO influence over the Euro-Mediterranean sector. Indeed, the detection of this signal is strongly affected by the large internal variability that characterizes the atmospheric circulation in the North Atlantic–European (NAE) region. This study explores if and how the low-frequency variability of North Pacific sea surface temperature (SST) may impact the El Niño-NAE teleconnection in late winter, which consists of a dipolar pattern between middle and high latitudes. A set of idealized atmosphere-only experiments, prescribing different phases of the anomalous SST linked to the Pacific Decadal Oscillation (PDO) superimposed onto an El Niño-like forcing in the tropical Pacific, has been performed in a multi-model framework, in order to assess the potential modulation of the positive ENSO signal. The modelling results suggest, in agreement with observational estimates, that the PDO negative phase (PDO−) may enhance the amplitude of the El Niño-NAE teleconnection, while the dynamics involved appear to be unaltered. On the other hand, the modulating role of the PDO positive phase (PDO+) is not reliable across models. This finding is consistent with the atmospheric response to the PDO itself, which is robust and statistically significant only for PDO−. Its modulation seems to rely on the enhanced meridional SST gradient and the related turbulent heat-flux released along the Kuroshio–Oyashio extension. PDO− weakens the North Pacific jet, whereby favoring more poleward propagation of wave activity, strengthening the El Niño-forced Rossby wave-train. These results imply that there might be conditional predictability for the interannual Euro-Mediterranean climate variability depending on the background state

Aperitivo de soja.

De forma simples e de fácil compreensão, este manual ensina o processo para obtenção de aperitivo de soja, disponibilizando essa tecnologia a todos os interessados em fabricar e comercializar produtos à base de soja.bitstream/item/11869/2/00081990.pdfProjeto Minibibliotecas

Determinismo genético e molecular do metabolismo de diterpenos em Coffea spp.

Cafestol e caveol são os dois principais diterpenos presentes nos frutos de café. Esses compostos específicos do cafeeiro têm se mostrado importantes na saúde humana, induzindo alterações no colesterol e ações anti-cancerígenas. Apesar da sua importância, há pouca informação sobre os princípios genéticos e moleculares de seu metabolismo. Análises fenotípicas através de HPLC, com cafés de diferentes espécies (vários genótipos por espécie), indicam uma variabilidade importante para cafestol, caveol e 16OMC. As análises in silico dos EST de Coffea permitiram identificar cDNAs parciais correspondente a um gene de CPS, dois de KO e um de KS. Análises de expressão desses genes por RTq-PCR quantitativa, em tecidos separados durante o desenvolvimento dos frutos, estão em andamento. Resultados preliminares indicam que os quatro genes alvos apresentam expressão diferencial durante o desenvolvimento dos tecidos do fruto. Os resultados de expressão serão discutidos considerando o interesse na identificação dos genes potencialmente envolvidos na regulação da concentração de cafestol e caveol

Observation of Umklapp processes in non-crystalline materials

Umklapp processes are known to exist in cristalline materials, where they control important properties such as thermal conductivity, heat capacity and electrical conductivity. In this work we report the provocative observation of Umklapp processes in a non-periodical system, namely liquid Lithium. The lack of a well defined periodicity seems then not to prevent the existence of these scattering processes mechanisms provided that the local order of the systems i.e. the maxima of the static structure factor supply the equivalent of a reciprocal lattice vector in the case of cristalline materials.Comment: 13 pages P

Elastic constant dishomogeneity and Q2Q^2 dependence of the broadening of the dynamical structure factor in disordered systems

We propose an explanation for the quadratic dependence on the momentum $Q$, of the broadening of the acoustic excitation peak recently found in the study of the dynamic structure factor of many real and simulated glasses. We ascribe the observed $Q^2$ law to the spatial fluctuations of the local wavelength of the collective vibrational modes, in turn produced by the dishomegeneity of the inter-particle elastic constants. This explanation is analitically shown to hold for 1-dimensional disordered chains and satisfatorily numerically tested in both 1 and 3 dimensions.Comment: 4 pages, RevTeX, 5 postscript figure

On the origine of the Boson peak

We show that the phonon-saddle transition in the ensemble of generalized inherent structures (minima and saddles) happens at the same point as the dynamical phase transition in glasses, that has been studied in the framework of the mode coupling approximation. The Boson peak observed in glasses at low temperature is a remanent of this transition.Comment: Proceeding of the Pisa conference September 2002, 13 pages+ 4 figures, To be publiched by Journal of Physic