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Implementazione della Direttiva Quadro sulle acque (2000/60/CE) attraverso l'utilizzo dei macroinvertebrati bentonici.
Get PDFLo studio si concentra sullo studio della fauna a macroinvertebrati, per definire, attraverso l’utilizzo del macrobentos, lo stato/potenziale ecologico di alcuni corpi lacustri, come richiesto dalla Direttiva 2000/60/CE. Campioni biologici, di granulometria e chimica delle acque e dei sedimenti sono stati prelevati in 10 laghi appartenenti a due regioni italiane (Piemonte e Sardegna) seguendo il protocollo di campionamento nazionale.
Ai dati biologici sono stati applicati indici di diversità, di equitabilità e di ricchezza: questi mostrano che i laghi naturali presentano una comunità più eterogenea rispetto agli invasi. Le analisi statistiche (generalized linear mixed effect model e multivariata) applicate ai dati biologici e abiotici mostrano che l’ossigeno è il fattore che maggiormente influenza la comunità, ma è comunque l’insieme di più fattori a determinare la densità e la diversità di comunità, infatti anche la tipologia di sedimento influenza la ricchezza in specie di questi ambienti. L’applicazione dell’Indice di Qualità Bentonico ha inoltre permesso di evidenziare una buona separazione tra laghi profondi con scarso e buon contenuto di ossigeno a livello del fondo, e di fissare i valori di riferimento delle diverse classi di qualità ecologica secondo le richieste della Direttiva Acque. Questo ha quindi permesso ai macroinvertebrati di essere inseriti nel Decreto Classificazione (D. M. 260/2010). Le prime applicazioni del metodo Lake Habitat Survey, utile ai fini di una classificazione idro-morfologica degli ambienti lacustri, mostrano l’esistenza di correlazioni tra questo metodo e la composizione della comunità a macroinvertebrati
Reputation assessment in collaborative environments.
Get PDFThe popularity of open collaboration platforms is strongly related to the popularity of Internet: the growing of the latter (in technology and users) is a spring to the former.
With the advent of Web 2.0, not only the Internet users became from passive receiver of published content to active producer of content, but also active reviewers and editors of content.
With the increase of popularity of these platforms, some new interesting problems arise related on how to choose the best one, how to choose the collaborators and how evaluate the quality of the final work.
This evolution has brought much benefit to the Internet community, especially related to the availability of free content, but also gave rise to the problem of how much this content, or these people, may be trusted.
The purpose of this thesis is to present different reputation systems suitable for collaborative environments; to show that we must use very different techniques to obtain the best from the data we are dealing with and, eventually, to compare reputations systems and recommender systems and show that, under some strict circumstances, they become similar enough and we can just make minor adjustment to one to obtain the other
Inward rectifier potassium current in dopaminergic periglomerular cells of mouse olfactory bulb.
Get PDFInward rectifier potassium (Kir) channels are important for neuronal signalling and membrane excitability. In this work, patch-clamp techniques were used to characterize Kir channels in mouse dopaminergic (DA) periglomerular (PG) cells. These interneurons are critically placed at the entry of the bulbar circuitry, in contact with terminals of olfactory sensory neurons and with dendrites of projection neurons.
Perforated-patch configuration was adopted to record Kir current in DA-PG cells in thin slice. IKir could be distinguished from the hyperpolarization-activated current by showing full activation in < 10 ms, no inactivation, suppression by Ba2+ in a typical voltage-dependent manner and reversal potential nearly coincident with EK.
DA-PG cells are autorhythmic and are target of numerous afferents releasing a variety of neurotransmitters, although their properties and role remain elusive. Depolarization induced by Ba2+ blocks spontaneous activity, although the Kir current is not an essential component of the pacemaker machinery.
The current is negatively modulated by intracellular cAMP, as shown by a decrease of its amplitude induced by forskolin. Several neuromodulatory effects were tested on the Kir current of DA-PG cell. Activation of metabotropic receptors - known to be present on these cells - shows that the current can be modulated by a multiplicity of pathways. The Kir current can be increased, as observed with agonists of muscarinic, α1 noradrenergic and GABAA receptors, or IKir modulation can caused the opposite effect, i.e. agonists of D2, 5-HT and histamine receptors.
These characteristics of the Kir currents provide the basis for additional flexibility of DA-PG cells signaling and function
Declinazioni del "femminile" nell'antimodernismo tedesco. Ludwig Klages e i suoi contemporanei (1893-1933).
No full textAt the beginning of the 20th century, Johann Jakob Bachofen’s notion of the Maternal as the origin of all things opened a broader scholarly debate in which gender categories became critical tools against modernity. According to each scholar’s political view point, the Feminine is now perceived as the repressed Other of European history, a utopian alternative to modernity, linked to ideas such as archaism, naturalness or backwardness. The present study is an attempt to trace and explain the persistence of the Feminine in German Anti-Modernism and is something else than a contribution to the debate about the historical existence of matriarchies and the linked political and social implications.
Within this framework the reception of the matriarchy and of Bachofen’s theories by Ludwig Klages is compared with that of his contemporaries. Indeed, Klages’ radical employment of Bachofen’s matriarchy, considered as ‘feminine principle’ against the instrumental rationalism of the ‘masculine’ modernity, has a significant impact on his time. First of all his influence can be perceived in the so called Munich Cosmic Circle, of which Klages was one of the founder members together with Alfred Schuler and Karl Wolfskehl. Stefan George and the members of his Circle were also inspired by his work, as later the theorists of the Frankfurt School, especially Walter Benjamin, Max Horkheimer, Theodor Adorno and Ernst Bloch. Klages’ use of the “Feminine” is also compared with that of the feminist movement active in the same historical period, including the particular point of view supported by Franziska zu Reventlow in her novels.
Starting from the above-mentioned comparisons, the present study aims at demonstrating that the male-female dualism is crucial for the paradigmatic “struggle” for Bachofen and at defining the nature of the crisis of modernity
L'aumento del tono endocannabinoide, secondario al blocco del catabolismo di anandamide e 2-arachidonoilglicerolo, induce analgesia e modula l'attivazione gliale in un modello animale di emicrania.
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The transition process of industrial clusters in developing counties. A comparative study of furniture clusters in Damietta and Brianza.
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New approaches to cancer vaccination and immunotherapy, based on the optimization of the presentation of tumor antigens and stimulation of CD4 positive T helper cells.
Get PDFRecently we have shown that a number of murine tumors arising from mice of the Balb/c (MHC H-2d) strain, induced to express MHC class II molecule after transfection with CIITA (MHC class II transactivator) ( Accolla R.S. et al. 1986) can be rejected effectively, generating tumor specific T helper cell (TH) triggering, immunological memory and protection even against parental tumor (Meazza R. et al. 2003 ; Frangione V. et al. 2010; Mortara L. et al. 2006) . The aims of my PhD thesis were: a) - to assess whether the same results can be extended to tumors of different MHC background (H-2b); b) - to investigate, using knock-out C57Bl mice for dendritic cells, whether CIITA transfected tumor cells can act as “surrogate APC” for their tumor antigens in vivo. To this end, LLC (Lewis lung carcinoma, H-2b) cells were stably transfected with CIITA and selected for expression of MHC class II molecules. Parental tumor cells and CIITA-transfected cells (LLC-CIITA) were injected subcutaneously into C57/BL6 mice and tumor take and growth kinetics were assessed. Mice injected with LLC-CIITA cells were tumor-free for longer time than mice injected with parental tumor cells. The growth kinetics and the size of CIITAexpressing tumors were significantly reduced compared to the parental tumor.
Adoptive cell transfer of purified CD4+ TH cells from mice injected with LLCCIITA into naïve mice demonstrated that these cells were able to protect from LLC parental tumor growth. Taken together these results strongly suggest that, similarly to H-2d strain, also H-2b tumors can be rejected if expressing CIITAmediated MHC class II molecules, confirming the general applicability of our tumor vaccination model. To achieve the second goal we performed in vivo experiments in a novel transgenic mouse model named CD11.c DOG, in which it is possible to induce a conditional depletion of dendritic cells (DC) by diphtheria toxin (DT) treatment. These mice express the diphtheria toxin receptor (DTR) under the control of the promoter of the CD11c molecule, expressed preferentially in DC. Once injected with DT, dendritic cells are eliminated for the period of treatment up to 12 days. DT-treated CD11c.DOG mice where injected with LLC-CIITA tumor cells and tumor take and tumor growth was followed during time. We found that LLC-CIITA cells can be recognized and rejected better than parental tumor even in CD11c-DOG mice.
These results suggest that CIITA-tumor cells may act in vivo as surrogate APCs for their own tumor antigens and trigger and adaptive immune response mediated by CD4+ TH cells
Development of engineered nanoparticles for biomedical and industrial applications.
Get PDFIn this work four nanoparticle systems were designed: two for medical and two for industrial applications.
The purpose of the first part of my study concerns the manufacture of a NPs-enzyme system for cancer therapy: Fe3O4 NPs@APTES-DAAO. This system combine the magnetic properties of iron oxide nanoparticles (Fe3O4 NPs) with the ROS generating enzyme D-amino acid oxidase (DAAO) in order to efficiently direct the enzyme into the tumor and kill tumor cells.
The second medical system designed consists in magnetic iron oxide nanoparticles conjugated with the antibiotics teicoplanin. Similar to the previous system, Fe3O4 NPs@Teicoplanin wants to takes advantage of the magnetic character of NPs for a specific targeting of the antibiotic.
The two systems for industrial application were composed of Fe3O4 NPs conjugated to a cephalosporin C acylase (VAC) and a L-aspartate oxidase (LASPO) respectively. In industrial enzymatic application processes, immobilization of enzymes can offer several advantages, including the ability to be used repeatedly, improvement of enzyme stability and broadening the optimum pH range of enzyme. The first system Fe3O4 NPs@APTES-VAC allows the one-step conversion of cephalosporin C in 7-aminocephalosporanic acid, which is the precursor of in semisynthetic cephalosporins antibiotics. The second system Fe3O4 NPs@APTES-LASPO allows the resolution of a racemic mixture of D, L-aspartate
Multi-level approaCh to the study of exposure to nanoparticles.
No full textBackground and aims
Exposure to nanoaerosols (particles with diameter below 100 nm) is an important topic in epidemiological and toxicological studies and is deemed to be a major risk affecting human health, both for general population (exposed to “ultrafine particles” - UFP) and for workers (involved in the production or application of manufactured nanomaterials -MNM- and nanoparticles - NP). In fact, high concentrations of airborne nano-sized particles are associated with increased pulmonary and cardiovascular mortality. Further, recent studies assesse that UFP and NP can reach the deeper region of the respiratory system and overcome the alveolar barrier and enter the bloodstream, contributing to increased risk of cancer, thrombosis, and cardiovascular diseases. An increasing number of studies are indicating that the health risk deriving from exposure to airborne nanoaerosols is not adequately addressed by conventional exposure evaluation methods and strategies capable of measuring exposure against these attributes. In fact, in recent years, society has become increasingly sensitive to individual risks, and thus data on the exposure needs to be personalized. Therefore, airborne particle studies were performed in the recent years to identify the main UFP and NP sources and to characterize population exposure. In this regard, personal monitoring is considered as the only way to obtain accurate exposure data, which are critical to further reduce exposure misclassification in epidemiological studies. The drawback of such method, however, is the high cost of implementation and the associated small number of observations that tends to produce sample biases. For this reason, personal monitoring is often used as a complement in exposure models to assess air pollution exposures in health studies. These models use personal or household exposure monitoring, and appear well-suited to overcome the problem of achieving population representative samples while understanding the role of exposure variation at the individual level. The monitoring and characterization techniques discussed in this thesis aims to evaluate nanoaerosols exposure in terms of mass, surface-area and/or number concentration. These methods were developed and used to exposure characterization both in environmental and occupational settings. The goal of this PhD project is firstly to perform an exposure assessment of UFP using innovative techniques and strategies. Secondly, it will be shown that microenvironmental models are effective tool, capable to model exposure to UFP in populations and sub populations. Finally, newly developed strategies and techniques are applied in occupational settings, in order to perform an occupational exposure assessment for workers involved in the production or application of MNM and NP.
Materials and methods
Exposure to airborne pollutants can be determined using indirect exposure models or through a direct approach (i.e. air quality measurements). In this study, UFP concentrations in different urban microenvironments (ME) were firstly measured by personal monitoring in repeated sampling campaigns, along fixed routes in two Italian cities, in order to measure personal exposure in
transport MEs. Measurements followed a multi-parametric and multi-metric approach, including on-line monitoring of UFP Particle Number Concentration (PNC), mean diameter (mean d) and lung-deposited surface area (LDSA). Secondly, average daily UFP exposure of adult Milan subpopulations (defined on the basis of gender and then for age, employment or educational status), in different exposure scenarios (typical working day in summer and winter) were simulated using a microenvironmental stochastic simulation model. The basic concept of this kind of model is that time-weighted average exposure is defined as the sum of partial microenvironmental exposures, which are determined by the product of UFP concentration and time spent in each microenvironment. Furthermore, this thesis describes the development of an instrumental approach for measurement of NP exposures in occupational settings, which takes into account the major potential route of exposure and factors that may influence biological activity and potential toxicity of nanomaterials and incorporates a risk management approach: different methods were used to measure and assess occupational exposures to engineered nanoparticles (NP) with a multi-parametric approach: the first method involved off-line gravimetric analysis of filter samples collected with Low Pressure Impactor. The second method used different, hand-held, direct-reading instruments to obtain a time series of particle number concentrations (PNC), mean diameter and surface-area concentration for NP.
Results and conclusions
This thesis provides important insights into UFP exposure in urban environments, that should be considered in developing additional and larger studies on population’s exposure. First, continuous real-time monitoring provided the information necessary to define the influence of local sources or changes in local circumstances on UFP concentrations. In addition, continuous monitoring allowed for the evaluation of short-term particle concentrations and demonstrated temporal and spatial variability for the studied urban microenvironments. Further, the simulation model, used to estimate the average daily UFP exposure of adult subpopulations in a major Italian urban area and in different exposure scenarios, have defined that demographic and socio-demographic factors (e.g., gender, age, profession, instruction level), as well as environmental patterns, have to be considered as major determinants of pollutant exposure in urban environments. Furthermore, this research detected UFP levels and average particle sizes and their seasonal variability, as well as comprehensive information on average particle number and mass concentrations, sizes and surface area in various microenvironments within urban areas, which is fundamental to evaluate the variability of human exposure in urban environments and to support the relevance of traffic-related exposure for health. Thus, findings derived from this study may represent an important tool in the definition of health and social implication of UFP exposure for general population and to provide complete and accurate exposure assessment data for risk assessors, including exposure metrics, mostly relevant as health effects indicators. Finally, regarding occupational settings, this study defined an experimental protocol, which was intended to be useful in determining potential exposure to engineered nanomaterials and nanoparticles in the workplace with complementary approaches. These information may also be used to determine whether engineering controls are effective in preventing release of the engineered nanomaterials to the workplace atmosphere