The lifetime gender gap in Italy. Do the pension system countervails labour market outcomes?

In Italy large work career gender gaps currently exists, particularly regarding wages and activity rates. The paper investigates the issue looking at lifetime incomes, where from the one side all the career gaps tend to accumulate, from the other the redistribution acted by the pension system may mitigate the differences. Exploiting an original database on the entire work careers, we document how the pay gap constantly opens with age and how women tend to cumulate lower seniority. Both gaps have an impact in the pension calculation, so that the day after retirement gender differences are even higher. By means of a microsimulation model we show that the pension system partially countervails labour market outcomes, implying lower differences in lifetime incomes. However, due to the current transition to an actuarially neutral system, the effect is going to vanish in following decades, posing some concerns about future prospects of gender income inequality.

L’analisi dei bisogni di formazione in azienda e la progettazione di un intervento formativo

Oggi si parla tanto di formazione, a tutti i livelli, sia in ambito aziendale, che scolastico, che universitario. La seguente trattazione prende in esame, nel campo prettamente aziendale, alcuni aspetti delle due prime fasi del processo di formazione: l’analisi dei bisogni e la progettazione di un intervento formativo. La maggior conoscenza di alcune parti di esse può essere di supporto anche a chi lavora in altri contesti formativi, come quello universitario, per approfondire e migliorare i propri processi e per avvicinarsi meglio quindi ai propri obiettivi

Italiani e stranieri nelle imprese ferraresi

The paper presents the main results of a recent research which explores in depth some characteristics of social relations within and around the workplaces employing both Italian and immigrant workers. The study is founded upon two complementary standpoints: the Theory of Organizational Action, elaborated by Bruno Maggi, and Norbert Elias’ Theory of Established- Outsiders Figuration. In conclusion, taking into account the results of research, we illustrate some general principles on which migration policies should be based

Proline synthesis in developing microspores is required for pollen development and fertility

Background: In many plants, the amino acid proline is strongly accumulated in pollen and disruption of proline synthesis caused abortion of microspore development in Arabidopsis. So far, it was unclear whether local biosynthesis or transport of proline determines the success of fertile pollen development. Results: We analyzed the expression pattern of the proline biosynthetic genes PYRROLINE-5-CARBOXYLATE SYNTHETASE 1 & 2 (P5CS1 & 2) in Arabidopsis anthers and both isoforms were strongly expressed in developing microspores and pollen grains but only inconsistently in surrounding sporophytic tissues. We introduced in a p5cs1/p5cs1 p5cs2/P5CS2 mutant background an additional copy of P5CS2 under the control of the Cauliflower Mosaic Virus (CaMV) 35S promoter, the tapetum-specific LIPID TRANSFER PROTEIN 12 (Ltp12) promoter or the pollen-specific At5g17340 promoter to determine in which site proline biosynthesis can restore the fertility of proline-deficient microspores. The specificity of these promoters was confirmed by β-glucuronidase (GUS) analysis, and by direct proline measurement in pollen grains and stage-9/10 anthers. Expression of P5CS2 under control of the At5g17340 promoter fully rescued proline content and normal morphology and fertility of mutant pollen. In contrast, expression of P5CS2 driven by either the Ltp12 or CaMV35S promoter caused only partial restoration of pollen development with little effect on pollen fertility. Conclusions: Overall, our results indicate that proline transport is not able to fulfill the demand of the cells of the male germ line. Pollen development and fertility depend on local proline biosynthesis during late stages of microspore development and in mature pollen grains

Anti-Inflammatory activity of a polyphenolic extract from Arabidopsis thaliana in in vitro and in vivo models of Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative disorder and the primary form of dementia in the elderly. One of the main features of AD is the increase in amyloid-beta (Aβ) peptide production and aggregation, leading to oxidative stress, neuroinflammation and neurodegeneration. Polyphenols are well known for their antioxidant, anti-inflammatory and neuroprotective effects and have been proposed as possible therapeutic agents against AD. Here, we investigated the effects of a polyphenolic extract of Arabidopsis thaliana (a plant belonging to the Brassicaceae family) on inflammatory response induced by Aβ. BV2 murine microglia cells treated with both Aβ25⁻35 peptide and extract showed a lower pro-inflammatory (IL-6, IL-1β, TNF-α) and a higher anti-inflammatory (IL-4, IL-10, IL-13) cytokine production compared to cells treated with Aβ only. The activation of the Nrf2-antioxidant response element signaling pathway in treated cells resulted in the upregulation of heme oxygenase-1 mRNA and in an increase of NAD(P)H:quinone oxidoreductase 1 activity. To establish whether the extract is also effective against Aβ-induced neurotoxicity in vivo, we evaluated its effect on the impaired climbing ability of AD Drosophila flies expressing human Aβ1⁻42. Arabidopsis extract significantly restored the locomotor activity of these flies, thus confirming its neuroprotective effects also in vivo. These results point to a protective effect of the Arabidopsis extract in AD, and prompt its use as a model in studying the impact of complex mixtures derived from plant-based food on neurodegenerative diseases

Film deposition, X-ray diffraction and optical absorption of novel (R-NH3)2ZnCl4 hybrid perovskites

Organic-inorganic (CnH2n+1NH3)2MX4 hybrid perovskites (where M is a divalent metal and X a halide) are presently attracting much attention, due to their unique electronic properties and excellent film processability [1]. These self-assembling structures contain 2D semiconductor layers ((MX6)=) alternately stacked with organic ammonium layers. Excitons resulting from the low dimensionality of the semiconductor sheets have binding energy of several tenths eV, and are expected to have interesting potentialities for optoelectronic and electronic applications [2]. In this communication we report on the preparation and the basic X-ray and optical characterization of the novel (CnH2n+1NH3)2ZnCl4 (1<n<6) compounds, deposited as thin films by spin-coating alcoholic solutions of stoichiometric precursors on glass and quartz substrates. X-ray diffraction data prove that the as-prepared films are single phase, well crystallized and with a dominant in-plane grain orientation. The distance between the inorganic sheets, as measured through the "d" parameters, linearly increases with the amine chain length ("n" value) (Fig.1a), thus suggesting that the organic chains are ordered perpendicularly to the film surface. The diffraction pattern refinement is presently in progress, in order to assign the appropriate space group and to determine the in-plane lattice parameters. Room temperature optical absorption spectra exhibit a maximum at about 240 nm, which is almost independent on "n" (Fig.1b). Such finding is consistent with the results we obtained in the homologous series of Cu-based hybrids [3] and suggests that also in the Zn-compounds the optical absorption phenomena are related to the inorganic cluster of the structure. References. [1] D.B.Mitzi, K.Chondroudis, C.R. Kagan, IBM J.Res.Dev. 45, 29-45, 2001; [2] M.Era, S.Morimoto, T.Tsutsui, S.Saito, Appl.Phys.Lett 65, 676-678, 1994; [3] F.Chiarella, A.Zappettini, T.Besagni, F.Licci, A.Cassinese, M.Barra, R.Vaglio, C.Aruta, Cryst.Res.Technol. 40, 1028-1032, 2005

Stability improvement of PMMA and Lumogen® coatings for hybrid white LEDs

Hybrid white LEDs employing perylene-based dyes for the frequency down-conversion of blue light, generated by a standard inorganic source, suffer from colour rendering variations due to the degradation of the organic molecule under prolonged irradiation. To avoid such inconvenient, proper encapsulation of the dyes in resins or other polymer matrices can prevent their accelerated ageing; nevertheless, embedding polymers can also exhibit significant bleaching caused by chemico-physical agents. Among all, polymethyl methacrilate (PMMA) is one of the most used materials for the fabrication of hybrid LEDs' colour conversion coatings, therefore its stability needs to be investigated

A new approach for the synthesis of ZnO nanoparticles sensitized with metal chalcogenides

The present communication is a response to renewed interest in nanostructure based "coupled compounds", like ZnO-MeX (where Me = Cd, Pb,... and X = S, Se) which can find extensive use in the fabrication of a number of solid state devices, such as photoconductive, solar cells, electroluminescent cells, photocatalysts. Various oxide semiconductors, like TiO2 and ZnO, are known to have appropriate properties for these applications, although there are some drawbacks associated with their use: (i) charge carrier recombination occurs within a few nanoseconds, (ii) band edge absorption threshold does not allow the utilization of visible light. One of the main approaches to overcome these particular limitations involves the contact of the semiconductor particle with another semiconductor, called "sensitizer". For example, this is the case of nanostructured ZnO particles combined with metal chalcogenides. Infact it is known that in these coupled systems the absorption threshold is extended to the visible region and the photogenerated electrons are quickly transferred from sulphide/selenide layer into to the lower lying conduction band of ZnO, thus limiting recombination effects. In order to produce this type of material we have combined ZnO nanoparticles, in the specific "tetrapod" morphology, with nanoparticles of metal chalcogenides. The main innovative aspects of the preparation procedure are the following: &#61485; the use of appropriate organic solvents to keep both ZnO and the formed metal chalcogenides completely suspended and dispersed in the liquid; &#61485; an in situ direct formation of metal chalcogenides keeping pH value in the range 6-8 (no use of ammonia salt or complexing agents); &#61485; the limited use of chemical reagents, i.e. only metal and sulphur/selenium precursors are involved; &#61485; the possibility to deposit the "coupled compounds" in form of thin films directly from the liquid suspension onto the substrates (silicon, alumina, glass, TCO layers, etc.). This paper reports details on the preparation procedure, results of morphological and structural investigations (XRD, SEM), compositional analysis (EDS microanalysis) and optical-electrical measurements (I-V, impedance spectroscopy, etc.), which point out the great potentiality of the proposed method for the synthesis of different "sensitized nano-compounds"

Enhanced aldehydes detection by ZnO nano-tetrapod based gas sensors

Metal oxides are very important materials in gas-sensing and the possibility to obtain them as crystalline nanostructures represents an essential chance to improve sensors sensitivity an lifetime. Zinc oxide (ZnO) is a versatile material that is today widely studied because of the large number of possible application fields. The availability of this material in a large number of nanostructures makes it very interesting for the realization of gas sensors. In this field ZnO nano-tetrapods can find a suitable and reliable application, since they can be obtained by vapour phase growth, starting from metallic Zn, with very large yield and low production costs. In the present work authors report the excellent results obtained in: (i) developing an optimized growth process for the production of ZnO tetrapods, (ii) realizing a gas sensing device based on these nanostructures and (iii) the very promising results obtained in the detection of some volatile organic compounds (VOC). In particular a very high response and a remarkable sub-ppm detection limit is demonstrated for aldehydes. Furthermore, the reaction mechanisms, which take place on the surface of ZnO tetrapods, are discussed as a function of temperature and it is shown that the response curves measured at different temperatures can provide a powerful tool for adding selectivity to aldehydes detection towards particular interfering compounds (e.g. alcohols)

Adjoint-based passive optimization of a micro T-mixer

LAUREA MAGISTRALEIn questo lavoro viene presentato un processo di ottimizzazione, basato sul metodo aggiunto, delle caratteristiche di mescolamento di un micro T-mixer. Oltre all’interesse tecnologico del problema specifico, la procedura intende anche valutare l’usabilità pratica e la robustezza delle tecniche aggiunte nel contesto di librerie CFD a volumi finiti esistenti per problemi di flussi incomprimibili. In questo senso, la scelta di un caso geometricamente semplice come quello del T-mixer è da considerarsi naturale, essendo il presente lavoro un primo passo verso l’applicazione a casi più complessi. Un’ulteriore semplificazione del problema è data dalla natura laminare del regime di moto considerato. L’approccio utilizzato è quello dell’ottimizzazione di forma, da considerarsi come un caso parti- colare dell’ottimizzazione topologica. Una formulazione continua viene adottata; a seguito dell’introduzione di una specifica funzione costo per il problema in esame, le equazioni aggiunte e le relative condizioni al contorno sono state implementate mediante l’utilizzo del software open-source OpenFOAM allo scopo di calcolare la sensitività superficiale. L’ottimizzazione è applicata in uno specifico regime laminare, denominato vortex flow regime, dove il dispositivo presenta un’insufficiente capacità di mescolamento. In questo contesto gli effetti della diffusione numerica portano a sovrastimare il grado di mescolamento. Per questo motivo diverse simulazioni numeriche su griglie differenti sono state effettuate per tenere sotto controllo gli effetti della diffusione numerica; una soglia, corrispondente ad una dimensione della cella di 3.0 μm, è stata identificata come la dimensione massima al di sotto della quale la soluzione non presenta cambiamenti qualitativi e i risultati dipendono marginalmente dalla risoluzione spaziale. Attraverso un solo passo dell’ottimizzazione e cambiamenti minimi della geometria, è stato possibile incrementare il grado di mescolamento di almeno due ordini di grandezza, mentre la caduta di pressione è rimasta pressoché invariata.Adjoint-based optimization is used to passively improve the mixing characteristics of a micro T-mixer thanks to the design of an improved geometry of the device. Besides the technological interest of the specific problem, the procedure is also meant to assess the practical usability and robustness of adjoint techniques in the context of existing finite-volumes CFD libraries for incompressible flow problems. The choice of a geometrically simple case, like that of the T-mixer, should be considered natural, being this work a first step towards more complex applications. A futher simplification is given by the laminar nature of the flow regime taken into account. A continuous adjoint formulation is adopted; after the introduction of a properly selected objective function for the problem at hand, adjoint equations and boundary conditions are implemented in the open-source software OpenFOAM to compute the surface sensitivity to the degree of mixing. We specifically target the laminar flow regime (i.e. the vortex flow regime) where the T-mixer shows a low mixing efficiency. It is well know that, in this regime, the numerical diffusion affects the results, and in particular leads to an overestimate of the degree of mixing. Several calculations on meshes of different size are used to keep resolution effects under control; a threshold, corresponding to cell lenght of 3.0 μm, is identified, below which the solution does not present further qualitative changes, and the results are marginally affected by further increases in spatial resolution. With only one optimization step, and rather small geometry changes, we are able to increase the degre of mixing by more than two orders of magnitude, while the pressure drop across the device is basically unchanged