Sicurezza nei cantieri post-sisma e prevenzione cadute dall'alto

Si considerano i rischi presenti nei cantieri della ricostruzione delle aree colpite dal sisma dell’Emilia del 2012. Il rischio dovuto a crolli improvvisi e a cadute dall’alto a causa di eventuali scosse sismiche, anche di assestamento, è considerato dal punto di vista della sicurezza degli operatori di cantiere. La strategia proposta per la mitigazione dei rischi per la sicurezza dei lavoratori è basata sulla pianificazione dell’emergenza e sulla programmazione delle fasi di cantiere. Il metodo di programmazione proposto è quello dei diagrammi tempo/spazio, integrato con la contestuale definizione dei rischi con il metodo del Risk Mapping. Il programma operativo delle opere che ne deriva, quale ad esempio il programma delle demolizioni, consente di definire per le aree di lavoro i fondamentali rischi presenti in ogni fase costruttiva, come ad esempio quello dei collasso intempestivo e quello di caduta dall’alto, e permette quindi la tempestiva azione preventiva e protettiva

Building information Modelling e Sicurezza

Il Building Information Modelling (BIM) è la capacità di progettare e controllare l’esecuzione della costruzione in un ambiente virtuale computerizzato, tridimensionale e dotato della dimensione temporale (4D), condiviso fra i principali operatori impegnati nel progetto. L’utilizzazione del BIM-4D per la sicurezza può migliorare la pianificazione della costruzione orientata alla sicurezza, fornendo layout di cantiere e piani di sicurezza più comprensibili per tutti gli operatori e può fornire una base per il controllo dell’assetto effettivo del cantiere ed essere il supporto per l’informazione, sia per l’individuazione dei fondamentali rischi presenti nel sito che per l’illustrazione delle relative misure preventive progettate. L’opportunità di utilizzare questa tecnologia per la pianificazione, la comunicazione e il controllo della sicurezza durante le fasi di costruzione è nota, ma all’atto pratico molte sono le problematiche ancora da risolvere, sia in relazione agli aspetti tecnologici/informatici che operativi

Tributyltin and mitochondria: new evidence in support of an uncoupling mechanism and further characterization of the transport mechanism

New evidence is given to support the hypothesis that the tributyltin compound (TBT) is an uncoupler of the oxidative phosphorylation in mitochondria. By means of an Arrhenius plot, it has been demonstrated that the transport kinetic of the TBT compound in mitochondria behaves in a manner which is similar to that obtained using classical uncouplers. The break point at 17 8C observed in the Arrhenius plot is interpreted as due to a phase change in the lipidic bilayer, since the TBT compound, like uncouplers and mobile carriers, is sensitive to the phospholipidic phase change. Therefore, we can confirm our previous hypothesis that, as TBT is an uncoupler it, like uncouplers, crosses the biological membranes by means of an electrophoretic mechanism. An understanding of this behaviour is essential when an explanation of the neurotoxicity of TBT is required

TCMS inhibits ATP synthesis in mitochondria: a systematic analysis of the inhibitory mechanism

The interactions of the antifouling compound TCMS (2,3,5,6-tetrachloro-4-methylsulphonyl pyridine) with rat liver mitochondria have been investigated. The results indicate that the compound inhibits ATP synthesis. Further investigations regarding the ATP syn- thesis mechanism suggest that TCMS inhibits succinic dehydrogenase of the mitochondrial respiratory chain. As the respiratory chain is similar in all living organisms, it can be concluded that the toxic effect of TCMS most likely depend on the different bioavailability of the compound and on the different importance of mitochondria in the ATP production in the animal species

A comparison between the responses of neutral red and acridine orange: Acridine Orange should be preferential and alternative to neutral red as a dye for the monitoring of contaminants by means of biological sensors

The acridine orange (AO) and neutral red (NR) dyes, commonly used as probes to measure the internal pH in acidic vesicles, are compared in this article. The comparison between the two dyes (arising from calculations taking into account their analytical constants) illustrated that the use of AO is preferential to that of NR because the AO response is sensitive over the whole pH range between 4.0 and 7.4, whereas the NR response is effective only between pHs 4.0 and 6.0. In addition, it became evident from the mitochondrial respiration response that NR, unlike AO, is a protonophore. When taken into consideration, these two properties suggest that AO is more suitable than NR as an indicator of toxicity measurements in water samples because the environmental toxic compounds induce pH changes in the acidic vesicles of biological structures that are used as environmental biosensors

Frozen mitochondria as rapid water quality bioassay

A rapid and relatively low cost bioassay, usable in routine screening water test has been developed modifying the beef heart mitochondria test. In our experiments, mitochondria (FM22) were frozen at 22 °C, instead of 80 °C (FM80), and their applicability and sensitivity was verified. The oxygen consumption was measured by a Clark elec- trode that was interfaced to a PC to collect test analysis data. Blank tests were carried out to verify the oxygen con- sumption linear fitting. Toxicity tests were performed using pure organic and inorganic compounds, such to verify the FM22 sensitivity. A piecewise regression, through an Excelâ Macro, identified the break-point in the oxygen con- sumption and calculated the toxicity. The IC50s of the tested compounds were calculated and ranged from 0.123 to 0.173 mg/l for heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and from 0.572 to 10.545 mg/l for organics (benzene, DMSO, DDE, endrin, dichloromethane, chlorobenzene, 1,2-dichlorobenzene and 1,3-dichlorobenzene). Water effluent samples were then tested. The FM22 gave different toxic reactions to them. Water samples were characterised for heavy metals. The FM22 bioassay had a higher sensitivity than the FM80 and a high reproducibility in the toxicity test with pure compounds. The FM22 test was a good predictor of toxicity for water samples; the bioassay is easy, low cost and rapid, then usable for routine tests

Assessing Environmental Impact of Green Buildings through LCA Methods: Acomparison between Reinforced Concrete and Wood Structures in the European Context

Life Cycle Assessment (LCA) can be used successfully to make decisions in sustainable building design and construction. Nevertheless, the method is rarely utilized for many reasons. First of all,in the common practice the energy consumption during the period of use is considered the main indicator of the environmental impactof buildings. Secondarily, databases relative to products, components and their installation cannot be found soeasily. The goal of this paper is tomake a comparison between two different construction technologies through Life Cycle Assessment methods, trying to understand the potentialities and the limitations of the available LCA tools. Although results may be limited to the specific context of Europe, we try to put in evidence the usefulness of the method in a design perspective, if carefully selected and adapted. The comparison regards two different structural solutions for a mid-sizedgreen building:an innovative wood structureand a reinforced concrete structure, built with a consolidated technology.According to the LCA approach,overall wood structures are environmentally less impactful thanconcrete ones, but different kinds of impact emerge in a wider perspective

Contribución al estudio de la industria quesera en la provincia de Buenos Aires

Desde el punto de vista de la higiene alimenticia, los quesos analizados, constituyen un producto de primer orden, conteniendo en reducido volumen, gran cantidad de sustancias cuaternarias y ternarias, como las albúminas y las grasas, cuerpos plásticos y dinamógenos, que además de servirnos para la formación y desarrollo de los tejidos, constituyen al mismo tiempo una fuente de calor y fuerza. La falta de adulterantes y el porcentaje en ázoe y grasa, considerando la sustancia seca, puede constituir para el higienista un alimento de elección para los individuos cuyo aparato digestivo funcione normalmente. Los elementos constitutivos de un determinado tipo de queso no pueden servirnos, por ahora, para establecer con ellos una clasificación química, porque sabemos que el mismo tipo, varía en sus componentes de una manera acentuada, según el periodo de maduración, según las razas de las vacas que producen la leche, según la clase de pasto que sirve para la alimentación, según la época de fabricación, etc., de ahí que necesitaríamos gran número de análisis del mismo tipo para sacar promedios que nos sirvieran á tal fin. Si consideramos que entre los 17 quesos analizados, 10 de los mismos están clasificados entre los blandos y los duros, dándonos por consiguiente un porcentaje del 59 % podemos decir que en la Provincia de Buenos Aires tenemos un tipo propio, especial del país, que propongo designar con el término de Semiduro. El método sistemático de análisis, las pequeñas modificaciones introducidas en el manual operatorio, la separación detallada de los diferentes nitrógenos, además de facilitar el trabajo analítico, constituye un medio para estudiar las causas de alteración y sabor en los quesos.Tesis digitalizada en SEDICI gracias a la Biblioteca Central de la Facultad de Ciencias Exactas (UNLP).Facultad de Ciencias Naturales y Muse