Hyperbolic predators vs parabolic preys

We present a nonlinear predator-prey system consisting of a nonlocal conservation law for predators coupled with a parabolic equation for preys. The drift term in the predators' equation is a nonlocal function of the prey density, so that the movement of predators can be directed towards region with high prey density. Moreover, Lotka-Volterra type right hand sides describe the feeding. A theorem ensuring existence, uniqueness, continuous dependence of weak solutions and various stability estimates is proved, in any space dimension. Numerical integrations show a few qualitative features of the solutions.Comment: 35 pages, 7 figure

IBVPs for Scalar Conservation Laws with Time Discontinuous Fluxes

The initial boundary value problem for a class of scalar non autonomous conservation laws in one space dimension is proved to be well posed and stable with respect to variations in the flux. Targeting applications to traffic, the regularity assumptions on the flow are extended to a merely $\mathbf{L}^{\infty}$ dependence on time. These results ensure, for instance, the well posedness of a class of vehicular traffic models with time dependent speed limits. A traffic management problem is then shown to admit an optimal solution

Non Local Conservation Laws in Bounded Domains

The well posedness for a class of non local systems of conservation laws in a bounded domain is proved and various stability estimates are provided. This construction is motivated by the modelling of crowd dynamics, which also leads to define a non local operator adapted to the presence of a boundary. Numerical integrations show that the resulting model provides qualitatively reasonable solutions

Differential Circadian Eating Patterns in Two Psychogenetically Selected Strains of Rats Fed Low-, Medium-, and High-Fat Diets

Spontaneous eating patterns in male, inbred Roman high- and low-avoidance rats (RHA/Verh, RLA/Verh) were continuously recorded while animals were successively offered three isocaloric (≍16.5-kJ/g) diets: a low-fat, high-carbohydrate diet (LF; 3.3% fat), a medium-fat diet (MF; 18% fat), and a high-fat diet (HF; 40% fat), the latter being followed once again by the LF diet. Under the conditions of this experiment, overall 24h food intake did not differ significantly between RHA/Verh and RLA/Verh rats, but was significantly higher for both rat strains on the MF and HF diets than on the LF diet. Despite the similar 24h-food intake, RHA/Verh rats ate transiently less than RLA/Verh rats during the third quarter of the dark phase under all dietary conditions. These differences were due to the RHA/Verh rats' longer intermeal intervals (with all diets) and smaller meals (with the MF and HF diets) and were compensated for during the last 3 h of the dark phase. On the LF diet, dark-phase meal frequency was higher and both nocturnal meal size and mean eating rate within meals were lower in RLA/Verh rats than in RHA/Verh rats. With the MF and HF diets, mean nocturnal meal size and meal duration were higher and mean eating rate was lower in RLA/Verh rats than in RHA/Verh rats. For both strains, nocturnal meal size was significantly higher with the MF and HF diets than with the LF diet, and nocturnal meal frequency was lower with the HF diet than with the other two diets. Although body weights were similar at the start of the study, RLA/Verh rats gained significantly more weight than did RHA/Verh rats by the end. As has often been the case with other aspects of behavior studied, differences in neuromodulatory systems (e.g., serotoninergic and dopaminergic) between RHA/Verh and RLA/Verh rats may directly or indirectly contribute to the subtle differences in eating patterns observed her

New Product Development in the Fashion Industry: An Empirical Investigation of Italian Firms

This paper investigates how companies in the fashion industry organize, plan and perform their New Product Development process (NPD). The results have been achieved through an empirical study carried out by the authors with the support of the GeCo Observatory, an Italian research initiative launched in 2012. This paper shows the details of eight selected case studies from the Italian fashion industry

Fast dispersion tailoring of multimode photonic crystal resonators

We introduce a numerical procedure which permits us to drastically accelerate the design of multimode photonic crystal resonators. Specifically, we demonstrate that the optical response of an important class of such nanoscale structures is reproduced accurately by a simple, one-dimensional model within the entire spectral range of interest. This model can describe a variety of tapered photonic crystal structures. Orders of magnitude faster to solve, our approach can be used to optimize certain properties of the nanoscale cavity. Here we consider the case of a nanobeam cavity, for which the confinement results from the modulation of its width. The profile of the width is optimized in order to flatten the resonator dispersion profile (so that all modes are equally spaced in frequency). This result is particularly relevant for miniaturizing parametric generators of nonclassical light, optical nanocombs, and mode-locked laser sources. Our method can be easily extended to complex geometries, described by multiple parameters

O Consórcio do Nordeste e o federalismo brasileiro em tempos de Covid-19

A pandemia do novo coronavírus, responsável pela doença Covid-19, trouxe grandes desafios para o Brasil, em especial a pactuação de estratégias para o combate à doença e a cooperação e coordenação governamental. A partir de análise documental e apreciação crítica sobre as relações federativas no Brasil, analisamos o contexto de criação do Consórcio Interestadual de Desenvolvimento Sustentável do Nordeste (Consórcio Nordeste) e sua atuação no enfrentamento à pandemia no contexto regional e nacional. Há uma falta de protagonismo do Governo Federal, em parte resultante da postura de menosprezo do Presidente da República acerca da gravidade da pandemia e de suas críticas às medidas de contenção da doença recomendadas por órgãos de saúde nacionais e internacionais e adotadas por parte significativa de estados e municípios brasileiros. Assim, concluímos que o Consórcio Nordeste tem desempenhado um papel preponderante também na escala nacional, ao contribuir efetivamente com medidas de enfrentamento à pandemia e com os grandes debates nacionais sobre a temática. A nosso ver, os conflitos e embates entre os entes federados no panorama da pandemia explicitam as tensões do federalismo brasileiro, o que nos permite elucidar desafios e alternativas para o aperfeiçoamento de nosso sistema político.The pandemic of the new coronavirus, linked to the Covid-19 disease, brought great challenges to Brazil, political issues related to how to define political strategies to fight against the disease and the currently governmental cooperation and coordination scope. Based on documentary analysis and critical appraisal of federative relations in Brazil, we analysed the context of the creation of the Interstate Consortium for Sustainable Development in the Northeast (Northeast Consortium) and its performance in tackling the pandemic in the regional and national context. There is a lack of protagonism from the Brazilian Federal Government, partly as a result of the President of the Republic's contemptuous stance on the seriousness of the pandemic and his criticisms of the disease containment measures recommended by national and international health agencies, adopted by a significant number Brazilian states and municipalities. Therefore, we concluded that the Northeast Consortium also played a leadership role on a national scale, effectively contributing to measures to deal with the pandemic and to the main national debates on the subject. In our point of view, the conflicts, and political disputes between federated entities in the panorama of the pandemic express the tensions of Brazilian federalism, which allows us to elucidate challenges and alternatives for the improvement of our political system.La pandemia por enfermedad del nuevo coronavirus implica grandes desafíos en Brasil, en particular acerca de la construcción de un acuerdo entorno de la mejor estrategia para combatir la enfermedad y para generar cooperación de los gobiernos federados. Con base en el análisis documental y la evaluación crítica de las relaciones federativas en Brasil, analizamos el contexto de la creación del Consorcio Interestatal para el Desarrollo Sostenible en el Nordeste (Consorcio del Nordeste) y su desempeño para enfrentar la pandemia en el contexto regional y nacional. Existe una falta de protagonismo del Gobierno Federal, en parte como resultado de la postura desdeñosa del Presidente de la República sobre la gravedad de la enfermedad y por sus críticas a las medidas de contención recomendadas por instituciones de salud nacionales y internacionales, adoptadas por un número significativo de estados y municipios brasileños. Por lo tanto, concluimos que el Consorcio del Nordeste también ha jugado un papel destacado en la escala nacional, contribuyendo de manera efectiva con medidas para combatir la pandemia y participando de los principales debates nacionales sobre el tema. En nuestra evaluación, los conflictos y enfrentamientos entre entidades federadas en el panorama de la pandemia revelan las tensiones del federalismo brasileño, lo que nos permite dilucidar desafíos y alternativas para la mejora de nuestro sistema político.L’un des plus grands défis posées par la pandémie covid-19 au Brésil concerne à l’articulation politique et institutionnelle entre les trois niveaux gouvernementaux. A partir de l’analyse des sources et d’un regard critique sur les rapports fédératives au Brésil, on examine le contexte de la création du Consortium Interétatique de Développement Durable du Nord-Est (le Consortium Nordeste) et son intervention régional et nationale face à l’actuelle pandémie. Une fois que le président de la République a minimisé l’attente de la pandémie, ainsi qu’a critiqué les mesures d’isolement proposées par les organismes internationales, les états et les municipalités, on peut conclure que le Consortium Nordeste a un rôle central à l’échelle régionale et nationale au même temps, ainsi que les conflits entre les entités fédératives montrent les tensions inhérentes au fédéralisme brésilien — ce qui nous permet d’élucider des enjeux et des alternatives vers le perfectionnement du notre système politique-institutionnel

Postharvest dehydration and defoliation

Background and Aims: Sfursat is an Italian wine produced with partially dehydrated Nebbiolo grapes in the Valtellina region which is located at high altitude. The research aims to understand the influence of fruit exposure on the rate of water loss by harvested fruit and the influence of exposure and dehydration on the content of phenolic substances and anthocyanins in the wine. Methods and Results: Clusters of Nebbiolo grapes from control vines (ND) and from vines that were defoliated at fruitset (DFS) or post-veraison (DPV) were harvested at a sugar concentration of about 230 g/L (there was no significant difference among the treatments), and dehydrated at 10, 20 or 30°C and at 60% relative humidity (RH), and air flow. Fruit were sampled at 10 and 20% weight loss (WL). Leaf removal had little effect on the physical characteristics of bunches and on the anthocyanins content and profile of harvested Nebbiolo grapes but affected dehydration. At 10 and 20°C, DFS fruit lost mass more slowly than DPV and ND fruit. In ND fruit, 20% WL reduced anthocyanins from 554 mg/kg fresh mass (FM) at harvest to 458, 432 and 396 mg/kg FM at 10, 20 and 30°C, respectively. In DFS and DPV berries, anthocyanins increased during dehydration at 10°C. At harvest, ND berries had a lower content of total stilbenes than those from defoliated vines. Dehydration (10°C, 20% WL) increased stilbene concentration in ND and DPV fruit. Dehydration at 10°C induced a rise in the flavonol concentration in fruit from defoliated vines. Catechin concentration was 106.5 mg/kg DM (dry mass), the highest value in ND berries at harvest. Wine was produced only from grapes dehydrated at 10°C. Wine from DFS fruit had a higher content of phenolic substances (2704.8 mg/L) and anthocyanins (104 mg/L) than that from DPV (2454.9 and 96.2 mg/L, respectively) and ND (2301.9 and 100.5 mg/L, respectively) fruit. Conclusions: Postharvest dehydration was slower where vines had been defoliated and resulted in changes in the ratios among groups of phenolic substances as well as among single phenolic components. Significance of the Study: In Nebbiolo grapes for Sfurzat wine production, defoliation at fruit set enables fruit to reach phenolic maturity at a lower sugar concentration allowing dehydration to increase sugar concentration without producing excessively alcoholic wines