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Biomedical subjects

O Sala

Publications and source records attributed to O Sala.

At least 19 recordsLinked to original sources
PubMed2001

Ecological forecasts: an emerging imperative.

Planning and decision-making can be improved by access to reliable forecasts of ecosystem state, ecosystem services, and natural capital. Availability of new data sets, together with progress in computation and statistics, will increase our ability to forecast ecosystem change. An agenda that would lead toward a capacity to produce, evaluate, and communicate forecasts of critical ecosystem services requires a process that engages scientists and decision-makers. Interdisciplinary linkages are necessary because of the climate and societal controls on ecosystems, the feedbacks involving social change, and the decision-making relevance of forecasts.

Agriculture↗
PubMed2000

A resonance Raman investigation on the interaction of styrene and 4-methyl styrene oligomers on sulphated titanium oxide.

In order to understand the nature of the interaction that gives rise to the yellow-orange colour observed when styrene or 4-methyl styrene are put in contact with sulphated TiO2, the resonance Raman spectra of such systems, including deuterated styrene (ring-deuterated d5 and perdeuterated d8) and allylbenzene were investigated. In all cases a substantial enhancement of the ring v(CC) stretching mode was observed. A charge transfer process involving a transition from the ring pi-electrons to the empty d-pi orbitals of titanium was ascribed responsible for the absorption in the visible. Two types of resonance Raman spectra were observed depending on the excitation wavelength, which can be explained by the presence of two kinds of oligomers, saturated and unsaturated, on the surface of the oxide with the former giving rise to a Raman enhancement at a higher excitation energy.

Polymers↗
PubMed2000

Evidences for a localized chromophore in the Ti(IV)/squarate complex: a resonance Raman investigation.

The present work continues a previous investigation on the interaction of oxocarbonic anions with highly charged metal ions. When squarate or croconate solutions are added to Ti(IV) acidic solutions, a rather strong and broad band shows up that is not present in the optical spectrum of the reagents. Excitation of the Raman spectrum of the resulting coloured solutions close to their absorption maxima leads to the enhancement of several modes of the oxocarbon. In particular the totally symmetric nu(C=O) mode of the Ti(IV)/squarate or croconate complexes shows an outstanding enhancement, a completely different behaviour of that observed in the Raman spectrum of the free oxocarbons, where the nu(CO) modes are barely observed. Such result indicates a rather strong Ti(IV)-oxocarbon interaction via the CO moieties with the formation of a strongly allowed LMCT (ligand to metal charge transfer) state. In addition the rather selective enhancement of the nu(CO) modes strongly suggests that the chromophore involved in the LMCT state is highly localized in the Ti(IV)-CO moieties of the complexes and that the enhancement mechanism involved is very likely the one described by Albrecht's A term, i.e. Franck-Condon one state mechanism.

Spectrum Analysis, Raman↗
PubMed1994

Cobalt exposure in 'hard metal' and diamonds grinding tools manufacturing and in grinding processes.

Cobalt is considered to play a major role in the development of 'hard metal' interstitial lung disease, asthma and other adverse health effects. A survey of occupational exposure of workers is a fundamental step to obtain exposure-response information and for preventive action. Process related exposure assessment was performed before and after technical control in small and medium size factories in a large surveillance programme. Cobalt containing airborne dusts were sampled by performing multiple measurements at the workplace of each process in which the types of job and duration of exposure were similar. Samples were analyzed by atomic absorption spectroscopy. Very high exposure levels encountered before technical control were significantly lowered with efficient local exhaust ventilation plant in 'hard metal' and grinding processes, but sometimes the TLV of 0.05 mg/m3 were exceeded. In the manufacture of grinding tools, major steps in cobalt control by local ventilation was not able to keep exposure below the TLV; exposures from 0.12 to 0.75 mg/m3 were recurrent and these need control strategies.

Air Pollutants, Occupational↗
PubMed1994

Exposure to cobalt in the welding process with stellite.

In some small factories producing moulds for ceramic tiles using a cobalt alloy (stellite), environmental and biological (CoU) monitoring was conducted for eight workers employed in gas-shielded arc (MAG) and oxy-acetylene welding processes. During oxy-acetylene braze-welding, the exposure to cobalt is very low as are urinary cobalt concentrations. On the other hand, during the MAG welding process, the exposure levels can exceed the TLV-TWA levels and correlated well with CoU at the end of a working shift. Two MAG welders followed for two consecutive weeks, showed different patterns of urinary cobalt excretion: under the same environmental conditions, the higher CoU was found in the worker with greater past exposure. This aspect needs further evaluation before adopting CoU as a current indicator of occupational exposure to the metal.

Air Pollutants, Occupational↗
PubMed1994

Cobalt powdersintering industry (stone cutting diamond wheels): a study of environmental-biological monitoring, workplace improvement and health surveillance.

This communication deals with an aspect of occupational hygiene in a factory producing granite cutting diamond wheels by sintering, in moulds, of fine cobalt powder. The factory has been studied between 1988 and 1991; the Department of Preventive and Occupational Medicine of the Local Sanitary Unit of Reggio Emilia has followed the evolution of the local exhaust ventilation equipment supplied by the employer in that period. At the same time, the following measurements and observations were carried out: (a) cobalt exposure by personal sampling, (b) airborne cobalt measurements by area sampling, (c) biological monitoring of cobalt in urine, (d) health surveillance.

Adult↗
PubMed1976

Tumour-host relationship and its implications in the treatment and long-term prognosis of laryngeal cancer. Critical observations on the TNM system of tumour classification.

The choice of surgical and/or X-ray treatment of a laryngeal cancer is usually established by taking into consideration the site of the tumor and its extension. The histologic type is considered only when this is easily identifiable, whereas the histologic grade of cellular differentiation and the tumour-host relationship are always erroneously disregarded. These latter factors are of a basic importance in establishing a "tailor-made" therapeutic programme for each patient and the long-term prognosis. The above factors have led to a new critical approach to laryngeal cancer and have also made it possible to obtain some practical results: 1 degrees the correct definition of the verrucous squamous cell carcinoma of the larynx, which is the result of the highest local defensive reaction to tumour growth (mediated by thymus-dependent lymphocytes); 2 degrees a criticism of the present trend to perform a more conservative surgery decided only opon the basis of the site and extension of the neoplasm; conservation surgery must be adopted for patients with an intense cellular immune response around the tumour and with a moderate histologic grade of malignancy; 3 degrees a criticism of the present criteria in establishing the long-term survival, which do not include the early immune response; 4 degrees the necessity of a systematic histologic study of the surgical specimen so as to evaluate the intensity of the immune reaction both around the tumour and in regional lymph nodes. In the light of these new data, the TNM system of tumour classification is now outdated, as witnessed by the constant efforts to adapt it to the unpredictable behaviour of malignant disease.

Carcinoma, Squamous Cell↗