169,968 research outputs found
La museografia tra rovine e città. Il ruolo della musealizzazione nella dialettica tra enclave archeologica e forma urbana
No full textIl contributo, tesi di Master, indaga il ruolo dell'attività architettonica e museografica nella relazione storica tra le rovine e il tessuto urbano attraverso l'analisi dei diversi modi in cui la città si è rapportata alle vestigia del proprio passato: dalla continuità nel riutilizzo degli edifici alla costituzione dei parchi archeologici urbani, passando per gli studi e i disegni dei pensionnaires e i progetti di riqualificazione contemporanea
Evaluation of Chlorella vulgaris and Scenedesmus obliquus growth on pretreated organic solid waste digestate
No full textIn this research Scenedesmus obliquus and Chlorella vulgaris growth was tested on digestate sludge obtained from the anaerobic co-digestion treatment of the organic fraction of municipal solid waste (OFMSW) together with waste activated sludge (WAS). Digestate was diluted 1:10 and tested in three batch experimental conditions: with no pre-treatments (noPT), after centrifugation (AC) and after filtration (AUF), in order to evaluate microalgae limiting growth factors. The best growth was obtained by C. vulgaris on digestate AC compared to S. obliquus, reaching 479 ± 31 cell million ml−1 and 131 ± 12 cell million ml−1 respectively. Ammonia removal evaluated in C. vulgaris and S. obliquus cultures was 99.2% ± 0.3 and 98.146% ± 0.008 in AC condition, respectively. Considering that AUF showed similar microalgae growth values, the digestate pretreatment for microalgae growth, could be limited to centrifugation
I poeti salutano Mandela
No full text[Traduzione con commento di contributo in volume] La lunga e gloriosa vita di Nelson Mandela è stata seguita attraverso gli anni da una coorte di poeti e scrittori che ne hanno celebrato il destino di coraggio e leadership. Insieme all’encomio e all’incitamento alla resistenza e alla lotta, essi gli hanno rivolto anche avvertimenti a tener viva la speranza attraverso le atroci sofferenze, e alta la guardia rispetto ai pericoli di un cammino aspro e rischioso. Da questa ricca messe letteraria, abbiamo scelto e tradotto in italiano tre testi che provengono da tre artisti di generazioni diverse e si pongono in tre momenti storici distinti e lontani l’uno dall’altro
Toxicity of untreated wood leachates towards two saltwater organisms (Crassostrea gigas and Artemia franciscana)
No full textWood is widely used in the development of freshwater, estuarine and marine coastlines. Timbers last according to their content of naturally occurring preservatives (mostly phenols and aldehydes), produced to prevent decay from biotic agents. When untreated woods are exposed to aquatic media, leachates are generated with likely toxic effects on the target environment. The potential impact on saltwaters of leachates from some untreated timbers of both native and tropical species has been assessed. The leaching procedure was set up considering British Standard test methods for paints and OECD guidelines for wood preservatives emission scenarios. Toxicity was monitored via the acute toxicity test with the brine shrimp Artemia franciscana and the sub-chronic embryotoxicity test with the oyster Crassostrea gigas. Brine shrimps evidenced no toxic effects while oysters discriminated well among leachates: the tropical wood species showed similar or relatively lower toxic effects than the native ones according to both leaching cycles (24 and 72 h). The ecotoxicological data have been integrated with some physical and chemical parameters
Influence of storage methods, refrigeration or freezing, on the toxicity of wastewater samples to oyster embryos.
No full textOne of the main concerns in wastewater whole effluent assessment is the sampling phase and the sample chain of custody before any toxicity evaluation. The major problem is related to establishing the correct method for sample storage in order to perform toxicity bioassays. The toxicity of some domestic and glass factory industrial wastewater samples stored both by refrigeration at 4 ± 1°C for no more than three days, and freezing at -18 ± 1°C for no more than one month was compared via the embryo larval development bioassay with the oyster Crassostrea gigas. The results showed no significant differences between the toxicities of refrigerated and frozen wastewater samples. The wastewater classification, according to a score based on four toxicity classes, showed that the preservation methods did not alter the toxicity classification of the samples. In particular, it was demonstrated that the samples considered as 'not acutely toxic' after refrigeration were also found to have this classification after freezing
Effects of mineral amendments on trace elements leaching from pre-treated marine sediment after simulated rainfall events
No full textBauxite extraction by-products (red mud) were used to evaluate their potential ability to stabilize trace elements from dredged and aerated/humidified marine sediment. The investigated by-products were: bauxaline®(BX) that is a press-filtered red mud; bauxsol™(BS) that is a press-filtered red mud previously washed with excess of seawater, and gypsum neutralized bauxaline® (GBX). These materials were separately mixed to dredged composted sediment sample considering 5% and 20% sediment: stabilizer ratios. For pilot experiments, rainfall events were regularly simulated for 3 months. Concentrations of As, Mo, Cd, Cr, Zn, Cu, and Ni were analyzed in collected leachates as well as toxicity. Results showed that Cd, Mo, Zn, and Cu were efficiently stabilized in the solid matrix when 20% of BX, BS, and GBX was applied. Consequently, toxicity of leachates was lower than for the untreated sediment, meaning that contaminants mobility was reduced. A 5% GBX was also efficient for Mo, Zn and Cu stabilization. In all scenarios, As stabilization was not improved. Compared to all other monitored elements, Mo mobility seemed to depend upon temperature-humidity conditions during pilot experiments suggesting the need of further investigations
Influence of storage methods, refrigeration or freezing, on the toxicity of wastewater samples to oyster embryos
No full textOne of the main concerns in wastewater whole effluent assessment is the sampling phase and the sample chain of custody before any toxicity evaluation. The major problem is related to establishing the correct method for sample storage in order to perform toxicity bioassays. The toxicity of some domestic and glass factory industrial wastewater samples stored both by refrigeration at 4 ± 1°C for no more than three days, and freezing at -18 ± 1°C for no more than one month was compared via the embryo larval development bioassay with the oyster Crassostrea gigas. The results showed no significant differences between the toxicities of refrigerated and frozen wastewater samples. The wastewater classification, according to a score based on four toxicity classes, showed that the preservation methods did not alter the toxicity classification of the samples. In particular, it was demonstrated that the samples considered as 'not acutely toxic' after refrigeration were also found to have this classification after freezing
Overview on ecotoxicological studies performed in the Venice Lagoon (Italy)
No full textThis work reports on the state of the art of the bioindicators used to assess environmental quality (regarding
chemical pollutant impacts) in the Venice lagoon. After a brief description of the roles, advantages and limitations
of bioindicators inmarine and transitional environments and a summary of the Venice lagoon characteristics, the
ecotoxicological methods used during scientific studies and research projects in the Lagoon are reported. Since
not all data are available and no database can be formulated, the main evidence from toxicity bioassays,
biomarkers and bioaccumulation analyses since the end of the 1970s is spatially synthesized using maps and
discussed according to the four Venice lagoon basins. The majority of indicators showed that the Lido basin
(north-central lagoon), affected by the presence of the industrial area and the city ofVenice, is the onemost highly
impacted (particularly in the sites located within or in front of the industrial area, which showed very high
sediment toxicity and high levels of DNA damage). The Malamocco basin (south-central lagoon) seems to be the
least problematic. The southern basin (Chioggia basin) was shown to be impacted by urban contaminants from
the town of Chioggia. The northern basin (Treporti basin) presented both impacted sites (high toxicity and high
bioaccumulation factor) and relatively unpolluted sites (absence of toxicity, absence of imposex and lowlevels of
bioaccumulation). This review can serve as a basis on which to select pragmatic, cost-effective biomonitoring
techniques for environmental effects in lagoon ecosystems
A three year follow-up of low grade squamous intraepithelial lesions: Persistence of lesions is significantly influenced by the presence of high risk papillomaviruses
No full textA cohort of 921 patients with low-grade squamous intraepithelial lesions (LG-SILs) was studied every six months for a period of 3 years by cytology and colposcopy. Regression of the initial cell injury to a normal cytology was observed in 585/921 cases (63.5%), while cytological abnormalities were still present at the same or higher grade, after three years, in 336/921 cases (36.5%). A sample of 122 Papanicolaou (Pap}stained cervical smears from the cohort of 921 LG-SILs were processed by an in situ hybridization (ISH) assay to search for the presence of DNA of human papillomaviruses (HPVs) considered at high oncogenic risk: 16/18 and 31/35/51. HPV DNA typization was positive for 47/122 lesions (38.5%). Among these 47 lesions associated with high risk HPV DNA, 12 (25.5%) healed and 35 (74.5%) persisted. Of the 75 HPV DNA negative lesions, 46 (61.3%) healed and 29 (38.7%) persisted. The results are discussed in order to define a correct protocol of LG-SIL follow-up
- …
