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Biomedical subjects

G Giovanelli

Publications and source records attributed to G Giovanelli.

9 recordsLinked to original sources
PubMed2000

Predictive study on Tuscan extra virgin olive oil stability under several commercial conditions.

Industries aim to ensure extra virgin olive oil (EVOO) stability especially during commercial activities up to use by end consumers. The objective of this work was to set up predictive models of EVOO stability during commercial activities. Stability was studied on five lots of a batch of Tuscan virgin olive oil to simulate different commercial activities. Chemical, physical, and sensory analyses were carried out on EVOO samples. Experimental data were processed by multivariate analyses to select significant parameters and by regression analyses to set up kinetic models. A few parameters were found to be significant: hydroxytyrosol and tyrosol contents, carotenoid absorbance at 475 and 448 nm, alpha-tocopherol content, Rancimat induction time, and K(232). It was also shown that the stability of this EVOO was not significantly influenced by different uncontrolled bottling, transport, and storage conditions in supermarkets. Empirical models were set up to predict the time to reach a reference value for K(232).

Adult↗
PubMed1997

Newborns discriminate the rhythm of multisyllabic stressed words.

Three experiments were run to test whether newborns were able to discriminate different stress patterns in multisyllabic stressed Italian words that varied both in consonants and in number of syllables. A high-amplitude sucking procedure was adopted in which the experimental group heard 2 sets of stimuli alternating minute by minute, whereas the control group heard only a single set of stimuli. The results showed that stress patterns were discriminated in 2 disyllabic phonetically unvaried words (Experiment 1), in 2 trisyliabic consonant-varied words (Experiment 2), and in 2 sets of disyllabic words varied in consonants within and between words (Experiment 3). The alternation procedure proved to be suitable for examining newborns abilities of discrimination and categorization. It also lowered the participants rejection rate compared with the classic habituation procedure. The present results suggest that newborns are sensitive to words' rhythm, as carried by stress patterns, and that this prosodic information is salient even in the presence of substantial consonant variation.

Arousal↗
PubMed1997

Mt. Cimone Observatory: baseline station for the measurement of gaseous substances and radioactive tracers in the atmosphere.

An extensive research program to record atmospheric physicochemical parameters and to track climatological trends was established at a remote Alpine station at Mt. Cimone Observatory in Italy. The main features of the study are outlined briefly and the results thus far collected, including surface ozone, carbon dioxide, stratospheric NO2 and O3, and airborne radioactivity are provided.

Atmosphere↗
PubMed1987

Plasma adrenocorticotropin, cortisol, and dehydroepiandrosterone response to corticotropin-releasing factor in normal children during pubertal development.

The adrenocorticotropin (ACTH), cortisol, and dehydroepiandrosterone responses to synthetic human corticotropin-releasing factor (CRF) were studied in 28 endocrinologically healthy children (age 1-16 yr) and in six adult volunteers (age 24-42 yr). CRF was given as an intravenous bolus (1 microgram/kg body weight) between 0900 and 1000 hr. Significant increments in ACTH and cortisol levels after CRF were observed in all subjects, with an ACTH peak value of 48.2 +/- 3.4 pg/ml at 10 min (p less than 0.001). The ACTH and cortisol response patterns after CRF did not change with age or pubertal maturation and did not differ in children and in adults. In contrast, the dehydroepiandrosterone response to CRF clearly was related to the stage of pubertal development. The peak value after CRF significantly increased from puberty stage 1 to puberty stage 5 (164 +/- 18 versus 779 +/- 86 ng/100 ml, p less than 0.001). In adults, the mean dehydroepiandrosterone peak value after CRF did not differ from that of P5 children. These results show that CRF can be given safely to children. The absence of age-dependent ACTH and cortisol responses and a dehydroepiandrosterone response changing with pubertal maturation points to the existence of factors involved in the control of adrenal androgen production other than ACTH.

Adolescent↗
PubMed1975

A comparative study of serum growth hormone and plasma cortisol levels in stimulation tests with insulin and propranolol-glucagon.

Insulin and propranolol-glucagon stimulation tests were carried out on 28 children and 5 adolescents and the results of their growth hormone and plasma cortisol estimations were compared. Twenty-nine subjects with normal growth hormone reserves showed a mean maximum rise of 17.4 muU/ml of serum growth hormone in the insulin test whereas the intramuscular injection of glucagon after oral premedication with propranolol produced a rise of 38.5 muU/ml. Five subjects with normal growth hormone reserves showed a reduced hormone output in the insulin stimulation tests but normal response in the propranolol-glucagon stimulation tests. Only one subject showed a poor response in the propranolol-glucagon but normal response in the insulin stimulation test. In 30 subjects with normal adrenocortical function the mean maximum increase of plasma cortisol was 15.6 muU/ml in the insulin - and 14.9 muU/ml in the propranolol-glucagon stimulation tests, respectively. Both methods are suitable for studying the pituitary-adrenocortical interrelationships. The mechanism of the release of glucagon-induced growth hormone is not clear but the fall in blood glucose does not seem to play a major role in the process. A stress-like mechanism is equally unlikely because vegetative symptoms occurred only i a small number of subjects after intramuscular glucagon administration. It is possible that glucagon possesses a releasing-like mechanism which operates in the pituitary itself.

Adolescent↗