3,266 research outputs found
STABILIZZAZIONE CHIMICO-BIOLOGICA DEI FANGHI DI DEPURAZIONE MEDIANTE LETTI FILTRANTI VEGETATI
Il lavoro di tesi proposto è una ricerca mirata alla disidratazione e stabilizzazione di fanghi biologici mediante una specie vegetale, Phragmites australis, in letti drenanti già presenti negli impianti di depurazione.
La macrofita radicata partecipa alla disidratazione, mediante evapotraspirazione, del fango di depurazione e crea le giuste condizioni affinché i batteri presenti nella rizosfera compiano una progressiva mineralizzazione e stabilizzazione della sostanza organica.
Gli impianti di depurazione utilizzati per questa sperimentazione sono localizzati nella provincia di Pisa (Oratoio e La Fontina) e rappresentano realtà medio-grandi (10.000-30.000 ae). Sono state utilizzate vasche di supero preesistenti negli impianti, opportunamente impermeabilizzate, ricoperte da un substrato granulare (ghiaia) su cui sono stati impiantati i rizomi di Phragmites australis. Dopo circa un mese le piante si sono adattate e sono state pronte a ricevere i fanghi semiliquidi.
Le analisi sono state effettuate sia sui fanghi che sulle piante a cadenza trimestrale per l’intero arco di un anno.
Sono stati monitorati parametri chimico-fisici e biologici indicativi del ciclo dei principali nutrienti (N, P, C). Inoltre, particolare attenzione è stata rivolta all’analisi delle quantità di metalli pesanti assorbiti dalle macrofite impiantate.
I risultati preliminari mostrano il successo del processo di disidratazione e stabilizzazione dei fanghi. Infatti l’ azione della Phragmites australis ha portato:
1. una notevole diminuzione del volume (circa 80%) dei fanghi immessi nei letti,
2. lo sviluppo di colonie microbiche che hanno innescato i processi di mineralizzazione e umificazione della sostanza organica.
Notevoli sono i vantaggi economici ed ecologici ottenuti attraverso questo processo
Come NGN-A e concorrenza possono coesistere
2008-06-27Sardegna Ricerche, Edificio 2, Località Piscinamanna 09010 Pula (CA) - ItaliaNGN'08: Workshop su Next generation networks: architetture e serviz
Advanced neuroimaging methods and biomarkers applied to preclinical models of multiple sclerosis and amyothropic lateral sclerosis
New paradigms are developed in magnetic resonance imaging for the advanced diagnosis of neurodegenerative diseases. In particular, multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) preclinical research poorly focuses on functional connectivity in brain. Available animal models of MS and ALS are extensively used for analysis such drug testing and discovery of underlying mechanisms of pathogenesis. These diseases present, since neuronal lesions formation and neuroinflammation, a multilevel heterogeneity in mechanism of neurodegeneration and brain connectivity still not well understood. Moreover, they play a key role in pharmacological research, from the identification of a therapy target to the in vivo validation of the efficacy. More recently alterations in synchronized brain activity at rest in MS patients have been reported. At the best of our knowledge, functional imaging has not been applied yet in the assessment of new therapies in the preclinical models for MS and ALS. In this study, we aim to develop an innovative platform based on functional MRI in the resting state (rsfMRI), for the pre-clinical evaluation of new markers in MS and ALS. Moreover, the advancing in MRI techniques could assess new criteria of sensitivity and specificity in diagnosis; an additional analysis on diffusion MRI outcomes in MS preclinical models is added to this study
BIO-ECOLOGICAL AND ANATOMICAL ASPECTS OF THE EUROPEAN EEL ANGUILLA ANGUILLA (L. 1758)
Catadromous fish are considered important species for their ecological, economical, and cultural value. Because their complex life cycle, they are subjected to cumulative effects of anthropogenic threats that resulted in worldwide decline since the beginning of the 20th century.
Among the most iconic catadromous species, the European eel Anguilla anguilla (L.) has aroused considerable interest since ancient times, though, to date, many aspects of its life cycle remain relatively unknown. A. anguilla showed a progressively decline since the 1970s. Starting from 2007, has been protected by the European Council Regulation 1100/2007, and successively classified as Critically Endangered (CR). Although conspicuous efforts have been conducted, to implement knowledge and identify possible solutions to preserve the future survivorship of A. anguilla, there is an urgent need to gain further insights into its life history.
A review of the bibliography allowed me to obtain an updated state of the art of knowledge about the European eel life cycle, biology, ecology, allowing me to identify main topics that structured my thesis project. Topics have been developed with the general aim of providing a contribution to the implementation of the knowledge of the bio-ecology and anatomy of this species in relation to the various environmental and anthropic factors through a multidisciplinary approach that involved numerous sampling activities accompanied by complex data collection, laboratory experiments, and statistical analyses.
First, I demonstrated the presence of synaptic development in the olfactory bulb, in terms of morphology and density of dendritic spines, that is shaped according to a pattern linked to the migratory life stages of the European eel (glass eels and silver eels).
Second, I described the glass eels’ migration temporal peak for the first time in the central-western Mediterranean in relation to the effects of main environmental factors. I also identified a spatio-temporal variability between four sites in the western Mediterranean in terms of the peak of recruitment and the biometric and pigmentation patterns of glass eels. Moreover, I tested new floating traps as an alternative sampling method in three Sardinian estuaries to further deepen glass eels’ recruitment dynamics in Sardinia.
Third, I analysed eels’ survival and growth performances during a rearing experiment with wild glass eels. I estimated recapture and growth rates on marked and unmarked farmed eels after restocking after a four-year study. Results suggest a good readjustment to the wild environment and demonstrated that this technique could represents a valid alternative restocking approach. Furthermore, I studied eels’ growth also in terms of otoliths’ shape differences. I found a distinct clustering among rivers and lagoons, with more rounded otoliths shapes in eels from rivers than lagoons, but with annual body growth quicker in lagoons than in rivers, showing that eel’s growth can differ according to habitat types. I fitted Von Bertalanffy’s growth curves for female and male eels from a Sardinian stream, that exhibited the already-known sexual dimorphism in growth parameters with higher values in females.
Finally, I pinpointed an overall decrease in eels’ occurrence in the Sardinian river network because of dams’ building features and the time from their construction.
Achieved results might have several implications beyond the regional interest and add new points from which to start further investigations that, over specific actions, may guide the implementation of new studies and appropriate monitoring programs. Findings highlighted also an urgent need for collaboration between the various stakeholders, researchers, decision-makers, authorities, professionals, and common people as an essential step to creating a sense of awareness on the criticalities that impact this species and the need to mitigate them
Clupdate: uno strumento per l'aggiornamento del cluster Arcosu
Per permettere l’aggiornamento degli host con i file presenti nell’archivio, è stato creato il programma Clupdate. CLUPDATE_ROOT, con le sue sottodirectory, rispecchia la struttura stessa del cluster. Ogni host è presente o con una sua sottodirectory oppure in quanto appartenente a una categoria (gruppo di host) con una propria sottodirectory. Clupdate si utilizza specificando la destinazione (come un host o una categoria di host), un file da trasferire (o una cartella o un "glob", cioè "path" con "wild cards") e delle opzioni di funzionamento (copia ricorsiva dei file, crea backup dei file sostituiti etc).Given a file that describes the hierarchy of precedence between computer names and category names, and give a directory in which each subdirectory corresponds to a computer or a catergory (a set of computers), and assuming that the hierarchy has a tree structure, manipulates information concerning the hierarchy and concerning the files found in the subdirectories
System for backup on redundant fileservers
A pair of computers have been configured as redundant file servers. These computers are also used to backup files. User files, exported using NFS, are placed on fast hard disks (type SCSI), whereas much larger, though slower hard disks (type SATA) are used for backup of these files. This technical report describes the implementation of the system of file backup.Un paio di computer sono stati configurati come file server ridondanti. Questi computer sono usati anche per il backup (archiviazione) dei file. I file degli utenti, disponibili ad altri computer tramite NFS, risiedono su dischi (hard disk) veloci (tipo SCSI), mentre dischi molto pi`u grandi per`o lenti (tipo SATA) sono usati per il backup di questi file. Questo rapporto tecnico descrive l’implementazione del sistema di backup dei file
A model of second-degree Virtual Cut Nodes applied to Complex Networks in Ecological Landscape
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Follicular nodules (Thy3) of the thyroid: is total thyroidectomy the best option?
BACKGROUND: Identification of the best management strategy for nodules with Thy3 cytology presents particular problems for clinicians. This study investigates the ability of clinical, cytological and sonographic data to predict malignancy in indeterminate nodules with the scope of determining the need for total thyroidectomy in these patients. METHODS: The study population consisted of 249 cases presenting indeterminate nodules (Thy3): 198 females (79.5%) and 51 males (20.5%) with a mean age of 52.43 ± 13.68 years. All patients underwent total thyroidectomy. RESULTS: Malignancy was diagnosed in 87/249 patients (34.9%); thyroiditis co-existed in 119/249 cases (47.79%) and was associated with cancer in 40 cases (40/87; 45.98%). Of the sonographic characteristics, only echogenicity and the presence of irregular margins were identified as being statistically significant predictors of malignancy. 52/162 benign lesions (32.1%) and 54/87 malignant were hypoechoic (62.07%); irregular margins were present in 13/162 benign lesions (8.02%), and in 60/87 malignant lesions (68.97%). None of the clinical or cytological features, on the other hand, including age, gender, nodule size, the presence of microcalcifications or type 3 vascularization, were significantly associated with malignancy. CONCLUSIONS: The rate of malignancy in cytologically indeterminate lesions was high in the present study sample compared to other reported rates, and in a significant number of cases Hashimoto’s thyroiditis was also detected. Thus, considering the fact that clinical and cytological features were found to be inaccurate predictors of malignancy, it is our opinion that surgery should always be recommended. Moreover, total thyroidectomy is advisable, being the most suitable procedure in cases of multiple lesions, hyperplastic nodular goiter, or thyroiditis; the high incidence of malignancy and the unreliability of intraoperative frozen section examination also support this preference for total over hemi-thyroidectomy
Utilisation d'essais à 50Hz pour valider l'échauffement de GIS à 60Hz
International audienceLes appareillages haute tension sous enveloppe métallique (PSEM) développés en France subissent des essais d'échauffement généralement effectués à 50 Hz avant leur commercialisation. La question traitée dans cet article concerne la possibilité d'utiliser les résultats de ces essais pour conclure sur les performances de ces dispositifs pour des applications 60 Hz tout comme cela existe pour les appareillages ouverts. Des mesures de pertes ainsi que des modélisations électromagnétiques sont présentées et permettent d'établir des règles de passage d'un dispositif à l'autre
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