622 research outputs found
La sicurezza sul lavoro nelle attività svolte all’estero
Il contributo affronta le problematiche connesse alla tutela della salute e sicurezza sul lavoro in caso di attività svolte all’estero. In particolare, la prima sezione procede a un inquadramento della materia alla luce delle fonti internazional-privatistiche che intervengono in presenza di rapporti di lavoro con elementi di internazionalità , giungendo ad includere le norme italiane in tema di salute e sicurezza fra quelle di applicazione necessaria. La seconda sezione approfondisce gli obblighi disciplinati dal d.lgs. n. 81/2008, concentrando l’attenzione sull’attività di valutazione e documentazione dei principali rischi geo-politici connessi allo svolgimento delle missioni all’estero. Nonostante la diversità di situazioni di natura prevenzionale con le quali i datori di lavoro potrebbero doversi confrontare, appare sempre molto apprezzabile la predisposizione di specifici protocolli nei quali definire le procedure da seguire, le tempistiche da rispettare e la documentazione da produrre. The contribution addresses the issues related to the protection of health and safety in the workplace in case of activities carried out abroad. In particular, the first section provides a better framework for the subject in the light of the international-private sources that deal with employment relationships characterised by some elements of internationality. As a result, also the Italian occupational health and safety standards appear to be implementing rules. The second section examines the obligations provided by the legislative decree n. 81/2008, by focusing on the assessment and on the report of the main geo-political risks connected with work activities performed abroad. Despite the diversity of the preventive situations that employers might face, it seems crucial to prepare specific protocols in which to define the procedures to be followed, the timing to be respected and the documentation to be produced
La sicurezza sul lavoro nelle attività svolte all’estero
Il contributo affronta le problematiche connesse alla tutela della salute e sicurezza sul lavoro in caso di attività svolte all’estero. In particolare, la prima sezione procede a un inquadramento della materia alla luce delle fonti internazional-privatistiche che intervengono in presenza di rapporti di lavoro con elementi di internazionalità , giungendo ad includere le norme italiane in tema di salute e sicurezza fra quelle di applicazione necessaria. La seconda sezione approfondisce gli obblighi disciplinati dal d.lgs. n. 81/2008, concentrando l’attenzione sull’attività di valutazione e documentazione dei principali rischi geo-politici connessi allo svolgimento delle missioni all’estero. Nonostante la diversità di situazioni di natura prevenzionale con le quali i datori di lavoro potrebbero doversi confrontare, appare sempre molto apprezzabile la predisposizione di specifici protocolli nei quali definire le procedure da seguire, le tempistiche da rispettare e la documentazione da produrre
ESTree db: a Tool for Peach Functional Genomics
BACKGROUND: The ESTree db represents a collection of Prunus persica expressed sequenced tags (ESTs) and is intended as a resource for peach functional genomics. A total of 6,155 successful EST sequences were obtained from four in-house prepared cDNA libraries from Prunus persica mesocarps at different developmental stages. Another 12,475 peach EST sequences were downloaded from public databases and added to the ESTree db. An automated pipeline was prepared to process EST sequences using public software integrated by in-house developed Perl scripts and data were collected in a MySQL database. A php-based web interface was developed to query the database. RESULTS: The ESTree db version as of April 2005 encompasses 18,630 sequences representing eight libraries. Contig assembly was performed with CAP3. Putative single nucleotide polymorphism (SNP) detection was performed with the AutoSNP program and a search engine was implemented to retrieve results. All the sequences and all the contig consensus sequences were annotated both with blastx against the GenBank nr db and with GOblet against the viridiplantae section of the Gene Ontology db. Links to NiceZyme (Expasy) and to the KEGG metabolic pathways were provided. A local BLAST utility is available. A text search utility allows querying and browsing the database. Statistics were provided on Gene Ontology occurrences to assign sequences to Gene Ontology categories. CONCLUSION: The resulting database is a comprehensive resource of data and links related to peach EST sequences. The Sequence Report and Contig Report pages work as the web interface core structures, giving quick access to data related to each sequence/contig
The Human EST Ontology Explorer: a tissue-oriented visualization system for ontologies distribution in human EST collections
<p>Abstract</p> <p>Background</p> <p>The NCBI dbEST currently contains more than eight million human Expressed Sequenced Tags (ESTs). This wide collection represents an important source of information for gene expression studies, provided it can be inspected according to biologically relevant criteria. EST data can be browsed using different dedicated web resources, which allow to investigate library specific gene expression levels and to make comparisons among libraries, highlighting significant differences in gene expression. Nonetheless, no tool is available to examine distributions of quantitative EST collections in Gene Ontology (GO) categories, nor to retrieve information concerning library-dependent EST involvement in metabolic pathways. In this work we present the Human EST Ontology Explorer (HEOE) <url>http://www.itb.cnr.it/ptp/human_est_explorer</url>, a web facility for comparison of expression levels among libraries from several healthy and diseased tissues.</p> <p>Results</p> <p>The HEOE provides library-dependent statistics on the distribution of sequences in the GO Direct Acyclic Graph (DAG) that can be browsed at each GO hierarchical level. The tool is based on large-scale BLAST annotation of EST sequences. Due to the huge number of input sequences, this BLAST analysis was performed with the aid of grid computing technology, which is particularly suitable to address data parallel task. Relying on the achieved annotation, library-specific distributions of ESTs in the GO Graph were inferred. A pathway-based search interface was also implemented, for a quick evaluation of the representation of libraries in metabolic pathways. EST processing steps were integrated in a semi-automatic procedure that relies on Perl scripts and stores results in a MySQL database. A PHP-based web interface offers the possibility to simultaneously visualize, retrieve and compare data from the different libraries. Statistically significant differences in GO categories among user selected libraries can also be computed.</p> <p>Conclusion</p> <p>The HEOE provides an alternative and complementary way to inspect EST expression levels with respect to approaches currently offered by other resources. Furthermore, BLAST computation on the whole human EST dataset was a suitable test of grid scalability in the context of large-scale bioinformatics analysis. The HEOE currently comprises sequence analysis from 70 non-normalized libraries, representing a comprehensive overview on healthy and unhealthy tissues. As the analysis procedure can be easily applied to other libraries, the number of represented tissues is intended to increase.</p
Eficiência de protocolos de extração de RNA em diferentes tecidos do cafeeiro
In order to use sensitive techniques of molecular biology, such as the study of differentially expressed genes, a highqualityRNA in suitable quantities is necessary. Due to the presence of several varieties and often expressive quantities of secondarycompounds in plants, there is no standard method for the isolation of nucleic acids that can be used for all species. Polyphenols andpolysaccharides are the compounds that interfere the most in the extraction process, and when they are present, a low-quality RNAis produced. Four RNA extraction methods (CTAB method, Hot Borate, CONCERT and Tri Reagent), in four different coffee tissues(root, leaf, flower and fruit) were tested in this work, aiming at determining which method is more efficient. It was observed that theCTAB and Hot Borate methods, in which PVP and/or -mercaptoethanol were added and precipitation with LiCl was performed,presented more pure RNA, with no degradation observed in any of the tissues, being suitable for further gene expression analysis.High-quality RNA was not obtained from any tissue in the extraction with Tri Reagent, which includes the use of phenol, and thusexpression analysis was disturbed. The CTAB macroextraction method presented samples with the highest RNA quality and largestquantities in all tissues. Future works need to be carried out aiming the standardization of this macroextraction method.Para a utilização de tĂ©cnicas sensĂveis de biologia molecular, como o estudo de genes diferencialmente expressos, Ă©necessário a obtenção de um RNA de boa qualidade e em quantidades adequadas. Devido Ă presença de grandes variedades, efrequentemente grande quantidade de compostos secundários em plantas, nĂŁo existe um mĂ©todo padrĂŁo para o isolamento de ácidosnuclĂ©icos que possa ser utilizado para todas as espĂ©cies. Os polifenĂłis e os polissacarĂdeos sĂŁo os compostos de maior interferĂŞnciano processo de extração, e quando presentes geram um RNA de baixa qualidade. Nesse trabalho foram testados quatro mĂ©todos deextração de RNA (MĂ©todo CTAB, Borato quente, CONCERT e Tri Reagente), em quatro diferentes tecidos de cafĂ© (raiz, folha, flor efruto), objetivando-se determinar qual mĂ©todo Ă© mais eficiente. Foi observado que os mĂ©todos, CTAB e Borato quente, que possuĂama adição PVP e/ou -mercaptoetanol, e precipitação com LiCl, foram os que apresentaram RNAs mais puros e sem degradação emtodos os tecidos, e puderam ser utilizados para a análise de expressĂŁo gĂŞnica. Com a extração utilizando o TriReagente, que tem comobase o fenol, nĂŁo foi obtido RNA de boa qualidade em todos os tecidos e consequentemente nĂŁo foi possĂvel a análise de expressĂŁo. OmĂ©todo de macroextração CTAB foi o que apresentou amostras com RNA de melhor qualidade e em grandes quantidades em todosos tecidos. Trabalhos posteriores precisam ser realizados a fim de padronizar esse mĂ©todo para microextração
Experiences on corrosion inhibitors for reinforced concrete
Corrosion of carbon steel reinforcement is the most important cause of premature failure on reinforced concrete structures. Prevention of corrosion is primarily achieved in the design phase by using high quality concrete and adequate cover. Additional prevention methods are adopted when severe environmental conditions occur or on structures
requiring very long service life. Among these methods, corrosion inhibitors seem to offer a simple and cost effective prevention technique. They may be used both as a preventative techniques, if added to fresh concrete, and as a repair system, if applied on hardened concrete.
The performance of corrosion inhibitors for reinforced concrete structures affected by chloride induced and carbonation corrosion has been studied at PoliLaPP, Laboratory of Corrosion of materials "P. Pedeferri" of the Department of Chemistry, Materials and
Chemical Engineering "G. Natta", Politecnico di Milano, in the last 15 years.
Organic commercial admixed corrosion inhibitors delayed the occurrence of chloride induced corrosion. This result is related to two effects: reduction of the rate of chloride transport into concrete and increase of the critical chloride threshold.
Commercial migrating corrosion inhibitors (MCI) are able to delay time-to-corrosion of passive rebars in concrete subjected to chlorides ponding; this effect is mainly related to the reduction of chlorides diffusion coefficient. MCI can reduce the corrosion rate after
corrosion initiation only in carbonated concrete, nevertheless efficiency is low and residual corrosion rate is not negligible.
Commercial MCI can penetrate into concrete mainly through capillary sorption but penetration depth is limited to 20 mm.
The results obtained with nitrite-based inhibitor confirm literature data: the inhibitor is effective if the molar ratio [NO2 ]/[Cl ] is higher than 0.5-0.6; in carbonated concrete, due to insufficient amount of inhibitor, no significant effect has been observed on corrosion rate.
Among the tested organic substances, compounds containing carboxylic group showed the best results solution tests: pitting potential, time-to-corrosion and critical chloride content are similar to those obtained with sodium nitrite. In concrete tests, only one amine and one amino acid showed good performance increasing the critical chlorides threshold with respect to the reference condition. For carboxylate substances, a strong link was found between inhibiting properties and molecular structure
Ontology-based, Tissue MicroArray oriented, image centered tissue bank
<p>Abstract</p> <p>Background</p> <p>Tissue MicroArray technique is becoming increasingly important in pathology for the validation of experimental data from transcriptomic analysis. This approach produces many images which need to be properly managed, if possible with an infrastructure able to support tissue sharing between institutes. Moreover, the available frameworks oriented to Tissue MicroArray provide good storage for clinical patient, sample treatment and block construction information, but their utility is limited by the lack of data integration with biomolecular information.</p> <p>Results</p> <p>In this work we propose a Tissue MicroArray web oriented system to support researchers in managing bio-samples and, through the use of ontologies, enables tissue sharing aimed at the design of Tissue MicroArray experiments and results evaluation. Indeed, our system provides ontological description both for pre-analysis tissue images and for post-process analysis image results, which is crucial for information exchange. Moreover, working on well-defined terms it is then possible to query web resources for literature articles to integrate both pathology and bioinformatics data.</p> <p>Conclusions</p> <p>Using this system, users associate an ontology-based description to each image uploaded into the database and also integrate results with the ontological description of biosequences identified in every tissue. Moreover, it is possible to integrate the ontological description provided by the user with a full compliant gene ontology definition, enabling statistical studies about correlation between the analyzed pathology and the most commonly related biological processes.</p
Mechanisms of oxygenation responses to proning and recruitment in COVID-19 pneumonia
Purpose This study aimed at investigating the mechanisms underlying the oxygenation response to proning and recruitment maneuvers in coronavirus disease 2019 (COVID-19) pneumonia. Methods Twenty-five patients with COVID-19 pneumonia, at variable times since admission (from 1 to 3 weeks), underwent computed tomography (CT) lung scans, gas-exchange and lung-mechanics measurement in supine and prone positions at 5 cmH(2)O and during recruiting maneuver (supine, 35 cmH(2)O). Within the non-aerated tissue, we differentiated the atelectatic and consolidated tissue (recruitable and non-recruitable at 35 cmH(2)O of airway pressure). Positive/negative response to proning/recruitment was defined as increase/decrease of PaO2/FiO(2). Apparent perfusion ratio was computed as venous admixture/non aerated tissue fraction. Results The average values of venous admixture and PaO2/FiO(2) ratio were similar in supine-5 and prone-5. However, the PaO2/FiO(2) changes (increasing in 65% of the patients and decreasing in 35%, from supine to prone) correlated with the balance between resolution of dorsal atelectasis and formation of ventral atelectasis (p = 0.002). Dorsal consolidated tissue determined this balance, being inversely related with dorsal recruitment (p = 0.012). From supine-5 to supine-35, the apparent perfusion ratio increased from 1.38 +/- 0.71 to 2.15 +/- 1.15 (p = 0.004) while PaO2/FiO(2) ratio increased in 52% and decreased in 48% of patients. Non-responders had consolidated tissue fraction of 0.27 +/- 0.1 vs. 0.18 +/- 0.1 in the responding cohort (p = 0.04). Consolidated tissue, PaCO2 and respiratory system elastance were higher in patients assessed late (all p < 0.05), suggesting, all together, "fibrotic-like" changes of the lung over time. Conclusion The amount of consolidated tissue was higher in patients assessed during the third week and determined the oxygenation responses following pronation and recruitment maneuvers
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