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In this paper the results of a study of soil hydraulic properties and plant coverage of a landfill located in Piacenza (Po Valley, Italy) are presented, together with the attempt to put the hydraulic properties in relation with plant coverage. The measured soil water retention curve was first compared with the output of some pedotransfer functions taken from the literature and then with the output of the same pedotransfer functions applied to a reference soil. The landfill plant coverage was also studied. The relation between soil hydraulic properties and plant coverage showed that the landfill soils have a low water content available for plants and this fact, together with their lack of depth and compacted structure, justifies the presence of a nitrophilous, disturbed-soil vegetation type, dominated by ephemeral annual species (therophytes).

The work deals with the qualitative modifications of a Calcaric fluvisol after irrigation with fresh water and depurated pig-slurry effluents (aerobic and anaerobic treatment, and phytodepuration with a reed bed system). The accumulation of nutrients (nitrogen and phosphorus) and heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Zn) as total and as bio-available forms in the soil was evaluated, together with soil aggregate stability index, hydraulic conductivity of the saturated soil and the in situ infiltration rate. The experimental field was divided into three plots, and cultivated with silage maize for three years (2003-2005). Results showed that the irrigation with depurated and phytodepurated effluents produced significant changes in the soil chemical properties controlling soil permeability, and influenced the bio-available fraction of heavy metals., L’étude s’intéresse aux transformations qualitatives d’un Calcaric Fluvisol après irrigation avec de l’eau douce et des effluents de porcherie purifiés (traitements aérobie et anaérobie, phyto-épuration avec un système de roselière). On a évalué l’accumulation d’éléments (azote et phosphore) et de métaux lourds (Cd, Co, Cr, Cu, Ni, Pb, Zn) sous formes totale et biodisponible dans le sol, aussi bien que l’index de stabilité de structure des agrégats, la conductivité hydraulique du sol saturé et le taux d’infiltration in situ. Le champ expérimental a été partagé en trois parcelles et cultivé avec du maïs pendant trois ans (2003-2005). Les résultats montrent que l’irrigation avec les effluents purifiés et phyto-epurés a induit des changements significatifs dans les propriétés chimiques du sol qui en régulent la perméabilité et y a modifié la fraction des métaux lourds bio-disponibles., Il lavoro descrive le modifiche qualitative di un Calcaric fluvisol a seguito dell’irrigazione con acqua dolce ed effluenti suinicoli depurati (trattamento aerobico ed anaerobico, e fitodepurazione a flusso verticale). É stato valutato l’accumulo nel suolo di elementi nutritivi (azoto e fosforo) e di metalli pesanti (Cd, Co, Cr, Cu, Ni, Pb, Zn) in forma totale e biodisponibile, l’indice di stabilità di struttura degli aggregati, la conducibilità idraulica del suolo saturo e la velocità di infiltrazione in situ. Il campo sperimentale è stato diviso in tre parcelle e coltivato a mais per tre anni (2003-2005). I risultati mostrano che l’irrigazione con effluenti depurati e fitodepurati ha indotto variazioni significative nelle proprietà chimiche del suolo che ne regolano la permeabilità ed ha modificato la frazione bio-disponibile dei metalli pesanti., EQA - International Journal of Environmental Quality; Vol 5 (2010); 33-42

Nell'articolo vengono comparate le pratiche discorsive di due gruppi di lavoro all'interno della medesima istituzione (un servizio socio-psichiatrico) in rapporto all'attività di formulazione dei problemi che avviene durante le riunioni. Dal punto di vista metodologico lo studio combina una indagine etnografica con un'analisi qualitativa di otto riunioni che sono state registrate e trascritte; l'analisi qualitativa è stata condotta sulla base di tre dimensioni: la cornice di partecipazione, la polifonia, e la memoria condivisa. L'analisi mostra come i due gruppi – nonostante si muovano all'interno dello stesso quadro istituzionale – realizzino differenti organizzazioni dell'attività discorsiva. Da un lato la cornice istituzionale dà forma al lavoro discorsivo; dall'altro lato ciascun gruppo di lavoro sviluppa un repertorio di pratiche unico, in risposta ad un insieme di vincoli che includono quelli istituzionali, ma non sono da questi stessi esauriti.

This is a study about discursive practices of problem solving within a team of professionals who rehabilitate people with psycho-social problems. The study community is the team of Centro a.D., an organization located in the South of Switzerland. The research combines an ethnographic study of Centro a.D. with a qualitative analysis of recorded talk during team meetings. In particular, narrative analysis has been applied to study problem solving. An extensive history of team meetings has been considered; it was possible to recognize that some operations systematically occur in problem solving. The set of these operations is the corpus of Centro a.D’s working practices in relation to problem solving activity, i.e. layered narratives, old narratives as resources, contextualization, discursive simplification of the rehabilitation project, centralization of interaction. Examining the relationship between the problem solving activity and the institutional framework of Centro a.D., the research illustrates the extent to which problem solving is shaped by such a framework. Namely, planned solutions necessarily belong to a set of possible actions enabled by the institution and problem description must enable the planning of those kind of solutions that can be implemented within the institution. Therefore we can speak in terms of institutional narratives and non-institutional narratives: institutional narratives construct problems that open possibilities for action within a specific fragment of social reality.

In recent years, there has been a significant spread of Phytophthora infections in several countries, causing problems in the horticultural sector. In this article, cytological, histological and protein differences between resistant plants (Criollos de Morelos 334) and susceptible plants of Capsicum annuum L. infected with Phytophthora capsici were analyzed to evaluate morphological modifications and quantitative protein changes that could both be the target of infection and be involved in the response mechanism. On a morphological level, we carried out staining for cutin, cellulose, callose and to evaluate the oxidative stress of Capsicum annuum samples. Morphological information suggests that Phytophthora capsici causes severe damage to susceptible plants, but not to resistant plants, with damage limited mainly to the pith and the phloem. Differences in the deposition of callose between resistant, infected and non-infected plants were also observed, whereas this was not observed for susceptible, infected and non-infected plants. Since the deposition of callose was most intense in the xylem of infected resistant plants, this suggests that the accumulation of callose is a mechanism of resistance/defense against infection by Phytophthora capsici. One-dimensional protein analysis was performed using antibodies against TGase and actin. Uninfected susceptible plants and resistant plants (both infected and non-infected) have a very similar pattern of TGase accumulation but different from infected susceptible plants, indicating that the defensive mechanism of resistant plants might be based on the activation of specific TGase isoforms.