Instability of some unsteady viscous flows

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Introduction to Morphodynamics of Sedimentary Patterns

Morphodynamics is a new discipline that investigates the formation and development of sedimentary patterns, i.e. the shapes of the cohesionless or cohesive boundaries of water bodies, evolving in response to the action of flowing water. Sedimentary patterns occur in fluvial, transitional, coastal and submarine environments. Their fascinating forms (e.g. dunes, meanders, alluvial fans, deltas, lagoons, coastal bars, tidal ridges, submarine fans) have attracted the attention of scientists. They also play a major role in fluvial, coastal and offshore engineering. The present monograph is the first of a series planned by an Editorial Committee comprising the four Authors. It provides a phenomenological introduction to the variety of patterns that will be investigated in the future Monographs. It also introduces to the mathematical theory of Morphodynamics, clarifying its nature of free boundary problem for the interface between a flowing water-sediment mixture and an erodible boundary

Saving a World Treasure: Protecting Florence from Flooding

The Committee Firenze 2016, on the occasion of the 50th anniversary of the tragic 1966 flood, invited six engineers and scientists to form an International Technical Scientific Committee (ITSC) to assess the current status of flood protection for the city of Florence and identify steps to reduce the risk of flooding facing the city. In this final Report, ITSC concludes that Florence remains at risk to significant flooding and this risk grows each day. It is not a question of whether a flood of the magnitude of 1966 or greater will occur, but when. In fact, the level of protection that exists in Florence now is not on a level appropriate to the citizens and treasures that rest within the city. If, under current conditions, a 1966-like flood occurred, the consequences to human lives, treasures, properties and community infrastructure could be much more catastrophic than they were in 1966

Determinants of Vitamin D Levels in Italian Children and Adolescents: A Longitudinal Evaluation of Cholecalciferol Supplementation versus the Improvement of Factors Influencing 25(OH)D Status

Objective. This paper aims to assess 25(OH)D levels in Italian children and adolescents identifying risk factors for 25(OH)D deficiency and to evaluate whether a normal 25(OH)D value can be restored in 25(OH)D-deficient patients. Methods. We evaluated 25(OH)D levels in 679 Italian children and adolescents (≤10, 11–20, 21–30, and >30 ng/mL were defined as severe deficiency, deficiency, insufficiency, and sufficiency, resp.). Of these, 365 25(OH)D-deficient were followed up for 1 year; 205 were treated with cholecalciferol (Arm A: 400 I.U.) and 160 by improving the environmental variables influencing 25(OH)D levels (Arm B). Results. At cross-sectional evaluation, 11.3% showed sufficiency, 30.0% insufficiency, and 58.7% 25(OH)D deficiency. Mean 25(OH)D was 19.08±8.44 ng/mL. At the enrollment time (T0), no difference was found between Arms A and B with respect to distribution and 25(OH)D levels. At end time (T1) 26.0% (29.7% in Arm A versus 20.6% in Arm B) showed sufficiency, 38.4% (42.0% versus 34.4%) insufficiency, and 35.6% (28.3% versus 45.0%) 25(OH)D deficiency. Mean 25(OH)D level was 23.71±6.83 ng/mL. Conclusions. Neither changes of lifestyle nor 400 I.U. cholecalciferol supplementation alone appears to be sufficient to restore adequate 25(OH)D levels

Hydrocortisone malabsorption due to polyethylene glycols (Macrogol 3350) in a girl with congenital adrenal insufficiency.

BACKGROUND: Primary adrenal insufficiency is relatively rare in children and, if unrecognized, may present with cardiovascular collapse, making it a potentially life-threatening entity. CASE PRESENTATION: The proposita, 11 months old of age, was admitted for lethargy and severe dehydration. Blood pressure was 62/38 mm Hg, and biochemical measurements showed hyponatraemia, hypochloraemia, hyperkalaemia, and metabolic acidaemia. Renin activity was 1484 μU/mL; cortisol, 1.03 μg/dL (normal, 5-25 μg/dL); and corticotropin (ACTH), 4832 ng/L (normal, 9-52 ng/L). Adrenal deficiency was diagnosed, and replacement therapy with glucocorticoids and mineralocorticoids was initiated. After 40 days, ACTH was 797 ng/L. During follow-up, the patient started taking macrogol twice daily for constipation and experienced a significant increase in ACTH (3262 ng/L), which dropped to 648 ng/L when macrogol was stopped. After arbitrary reintroduction of macrogol, the child presented with hypoglycaemia, lethargy, weakness, and hypotonia; ACTH was 3145 ng/L. After again stopping macrogol, her ACTH was near normalized (323 ng/L). CONCLUSION: Hydrocortisone malabsorption may be caused by macrogol use. Because chronic constipation is frequently reported in children, the possibility that macrogol contributes to adrenal crisis should be taken in account

Prognostic Impact of the Indexation of Left Ventricular Mass in Patients Undergoing Dialysis

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Chlamydia pneumoniae, overall and cardiovascular mortality in end-stage renal disease (ESRD)

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Fatty Acids Composition of Stomach Oil of Scopoli’s Shearwater (Calonectris diomedea) from Linosa’s Colony

Calonectris diomedea is a Procellariforms seabird having a very representative colony in Linosa Island (Southern Italy). The adult forms of C. diomedea produce a pasty oil from their proven- triculus to feed their chicks during the rearing period. In this work, we examined the fatty acids composition of the stomach oil of C. diomedea from Linosa Island by gas chromatography with flame ionization detection (GC-FID). The samples were collected at 20 and 70 days after hatching. Twenty different fatty acids (FAs) were identified. Saturated fatty acids (SFA) were the most abundant in percentage (41.6%) at day 20 followed by polyunsaturated fatty acids (PUFA, 38.7%) and monounsat- urated fatty acids (MUFA, 19.7%). MUFAs were the most abundant in samples collected at day 70 (53.8%), followed by SFAs (36.6%) and PUFAs (9.8%). Oleic acid (C18:1ω9) in the samples on day 70 was 4 times higher than that in the samples on day 20. The Principal Component Analysis (PCA) verified a clear separation of the stomach oil samples in two groups, according to the day of sampling. The results obtained confirm the role of FAs analysis of stomach oil to understand the ecology and breeding behaviour of C. diomedea, highlighting a resemblance with signatures recorded in marine organisms of Linosa Island