Fuels with low octane number: water injection as knock control method.

The present paper deals with the study of water effect on the combustion of fuels with low Octane Number in Internal Combustion Engines. In particular, this study was carried out using a variable volumetric compression ratio CFR fuel engine. ASTM Standards for Motor and Research methods were followed to determine fuels and fuel-water mixture Octane Number. CFR fuel engine intake manifold was modified to install water injection. Different water/fuel mass ratios were used and Research and Motor Methods Octane Number and pollutant emissions were measured. In particular, water to fuel mass flow ratio was imposed from 0 to 1.5. Increasing the water/fuel mass ratio an increment in octane number was registered and this behaviour is evident for each base octane number studied. At the same time a reduction in the NOx emissions was registered due to both in-cylinder temperature reduction and water chemical interaction with NOx. Analysing in-cylinder pressure traces highlighted that water presence reduces pressure oscillation within the cylinder engine. On the basis of the results it is possible to state that water is able to control detonation in the fuel combustion and an increment of the octane number is registered.

[Registry of genetic and malformative diseases in the province of Macerata]. / Registro delle malattie genetiche e malformative della provincia di Macerata.

OBJECTIVES: The aim of this epidemiological research is to evaluate the prevalence of genetic diseases and malformative syndromes in paediatric population living in the Macerata county. MATERIAL AND METHODS: All the data were collected through a careful analysis of a specific questionnaire sent to all the family paediatricians. RESULTS: 23,379 children living in Macerata county, aged 0 to 9 years, were evaluated (93.8% of all this paediatric population). Among those were found N 400 cases of genetic diseases and malformative syndromes: Malformations Tot.N. 255 cases (63.3% of the reported cases); Malformative Syndromes Tot. N. 55 cases (27.8% of the reported cases); Endocrinology and Metabolic Diseases Tot. N. 41 cases (10.3% of the reported cases); Osteochondrodysplasia Tot. N. 22 cases (5.7% of the reported cases); Other Tot. N. 28 cases (7.0% of the reported cases); Male population was found more affected than female: M/F ratio = 1.4. The analysis of the data showed an increasing trend in detecting these pathological conditions, consistent with the increase in geographic altitude (3 areas considered): 0-100 meter = 0.88%; 100-600 m.a.s. = 1.34%; over 600 m.a.s. = 1.88%. CONCLUSION: The knowledge of the number of children affected by genetic and malformative diseases in the Macerata county is relevant in order to establish a Genetic Service with the aim to better support the medical assistance of these patients and counselling service for the families.

Effects of isolation on interferon production and hematological and immunological parameters.

A 27-year-old woman was maintained in an isolated state for 131 days in Carlsbad Caverns, New Mexico. Her diet was vitamin D-depleted. Determinations on the effects of such isolation on levels and activities of peripheral blood cells that are important for hematological homeostasis and immunological function were carried out. Throughout the duration of the study, the percentage of lymphoid cells that expressed CD3, CD4, CD8, CD19, Leu 8, and other markers remained relatively constant although the absolute numbers of these cells varied. Although the percentage of natural killer (NK) cells did not vary, the activity of these cells did change. NK cell activity became elevated as the isolation study progressed. Production of interferon-gamma (IFN-gamma) in response to mitogen stimulation was higher than expected throughout the isolation periods, but returned to the normal range after termination of the isolation. Red and white cell counts dropped significantly upon entering isolation, but soon returned to normal.