Volcanic Vortex Rings: Axial Dynamics, Acoustic Features, and Their Link to Vent Diameter and Supersonic Jet Flow.

By injecting a mixture of gas and pyroclasts into the atmosphere, explosive volcanic eruptions frequently generate vortex rings, which are toroidal vortices formed by the jet's initial momentum. Here, we report high-speed imaging and acoustic measurements of vortex rings sourcing from gas-rich eruptive jets at Stromboli volcano (Italy). Volcanic vortex rings (VVRs) form at the vent together with an initial compression acoustic wave, VVRs maximum rise velocity being directly proportional to the amplitude and inversely proportional to the duration of the compression wave. The axial rise and acoustic signature of VVRs match well those predicted by recent fluid-dynamic experiments. This good match allows using the high-frequency (80-1,000 Hz) component of the jet sound and the time-dependent rise of VVRs to retrieve two key eruption parameters: the Mach number of the eruptive jets (<1.5) and vent diameter (∼0.7 m), respectively, the latter being confirmed independently by direct Uncrewed Aerial Vehicle observations.

Surface ruptures database related to the 26 December 2018, MW 4.9 Mt. Etna earthquake, southern Italy.

We provide a database of the surface ruptures produced by the 26 December 2018 Mw 4.9 earthquake that struck the eastern flank of Mt. Etna volcano in Sicily (southern Italy). Despite its relatively small magnitude, this shallow earthquake caused about 8 km of surface faulting, along the trace of the NNW-trending active Fiandaca Fault. Detailed field surveys have been performed in the epicentral area to map the ruptures and to characterize their kinematics. The surface ruptures show a dominant right-oblique sense of displacement with an average slip of about 0.09 m and a maximum value of 0.35 m. We have parsed and organized all observations in a concise database, with 932 homogeneous georeferenced records. The Fiandaca Fault is part of the complex active Timpe faults system affecting the eastern flank of Etna, and its seismic history indicates a prominent surface-faulting potential. Therefore, this database is essential for unravelling the seismotectonics of shallow earthquakes in volcanic areas, and contributes updating empirical scaling regressions that relate magnitude and extent of surface faulting.

Anomalous Discharge of Endogenous Gas at Lavinio (Rome, Italy) and the Lethal Accident of 5 September 2011.

The Rome region contains several sites where endogenous gas is brought to the surface through deep reaching faults, creating locally hazardous conditions for people and animals. Lavinio is a touristic borough of Anzio (Rome Capital Metropolitan City) that hosts a country club with a swimming pool and an adjacent basement balance tank. In early September 2011, the pool and the tank had been emptied for cleaning. On 5 September, four men descended into the tank and immediately lost consciousness. On 12 August 2012, after a long coma the first person died, the second one reported permanent damage to his central nervous system, and the other two men recovered completely. Detailed geochemical investigations show that the site is affected by a huge release of endogenous gas (CO2 ≈ 96 vol.% and H2S ≈ 4 vol.%). High soil CO2 and H2S flux values were measured near the pool (up to 898 and 7.155 g·m-2·day-1, respectively), and a high CO2 concentration (23-25 vol.%) was found at 50-70 cm depth in the soil. We were able to demonstrate that gas had been transported into the balance tank from the swimming pool through two hubs connected to the lateral overflow channels of the pool. We show also that the time before the accident (60 hr), during which the balance tank had remained closed to external air, had been largely sufficient to reach indoor nearly lethal conditions (oxygen deficiency and high concentration of both CO2 and H2S).

Quality of local school wellness policies for physical activity and resultant implementation in Pennsylvania schools.

Background: In 2006, United States public schools participating in federal school meal programs were required to adopt school wellness policies. The effect of these policies on school nutrition environments is well documented; however, evaluation of physical activity policies has received less investigation. We aimed to evaluate how district wellness policies aligned to practice for physical activity implementation in 40 schools with high obesity rates (>24%). Methods: Wellness policies were evaluated using the validated Wellness School Assessment Tool (WellSAT). Concurrently, schools completed the validated Alliance for a Healthier Generation's Healthy Schools Program (HSP) self-assessment to evaluate physical activity practices. Overall, 13 of 20 physical activity measures from WellSAT and 12 of 13 physical activity measures from HSP were aligned to match policy with practice. Results: Most policy items scored 0 or 1, indicating either 'no mention in the policy' or 'containing weak or vague language'. Corresponding HSP results indicated that school physical activity practices are 'not in place' or 'under development'. A strong, positive, correlation (r = 0.92, P < 0.001) indicated that a significant relationship exists between policy and implementation. Conclusions: Results indicate that most districts currently have weak policies regarding physical activity, limiting the potential to positively influence school-based physical activity.

Bone turnover and density in obese premenopausal women during moderate weight loss and calcium supplementation.

Bone turnover is increased during weight loss in postmenopausal women and can be suppressed with calcium supplementation. In this study, we assessed the influence of energy restriction with and without calcium supplementation (1 g/day) in premenopausal women. Thirty-eight obese premenopausal women (body mass index [BMI] of 35.0 +/- 3.9 kg/m2) completed a 6-month study of either moderate weight loss or weight maintenance. During weight loss, women were randomly assigned to either a calcium supplementation (n = 14) or placebo group (n = 14) and lost 7.5 +/- 2.5% of their body weight. The control group of women (n = 10) maintained their body weight. Total body and lumbar bone mineral density (LBMD) and content were measured by dual-energy X-ray absorptiometry (DXA) at baseline and after weight loss. Throughout the study, blood and urine samples were collected to measure bone turnover markers and hormones. During moderate energy restriction, dietary calcium intake decreased (p < 0.05) and the bone resorption marker deoxypyridinoline (DPD) increased slightly (p < or = 0.05) without evidence of bone loss. Calcium supplementation during weight loss tended to increase lumbar BMD by 1.7% (p = 0.05) compared with the placebo or weight maintenance groups. In contrast to our previous findings in postmenopausal women, premenopausal obese women who consume a low calcium diet do not lose bone over a 6-month period, whether their weight is stable or decreasing moderately.

Moderate energy restriction increases bone resorption in obese postmenopausal women.

BACKGROUND: Weight reduction reduces bone mineral density (BMD) and increases the risk of osteoporosis. OBJECTIVE: We investigated whether bone is mobilized in postmenopausal women during energy restriction and whether hormones regulate bone turnover and mass. DESIGN: Twenty-seven obese postmenopausal women with a mean (+/-SD) age of 55.9 +/- 7.9 y and body mass index (in kg/m(2)) of 33.0 +/- 3.8 completed the 6-mo study. Fourteen women followed a moderate energy-restricted diet (WL group) and 13 control subjects maintained their body weight (WM group). Body weight, bone turnover markers, serum parathyroid hormone (PTH), and dietary intake were measured throughout the study. Total-body BMD, sex hormone binding globulin, leptin, and estrone were measured at baseline and at week 25. RESULTS: In the WL group, body weight decreased by 10.2 +/- 5.5% (P < 0.001), body fat mass decreased by 18.7 +/- 11.3% (P < 0.001), and total-body BMD decreased by 1.2 +/- 1.2%; these changes were significantly different from those in the WM group (P < 0.05). Serial measurements showed chronically elevated rates of bone resorption and formation during energy restriction that were greater than in the WM group (P < 0.05). Serum sex hormone binding globulin increased and leptin decreased with weight loss (P < 0.05). Serum PTH tended to increase in the WL group but not in the WM group (P < 0.06). The reduction in fat mass with weight loss was directly associated with a decrease in serum estrone (P < 0.01, R(2) = 0.50). CONCLUSIONS: Moderate energy restriction increases bone turnover in obese postmenopausal women and may be regulated in part by alterations in serum PTH and estrone.

Calcium supplementation suppresses bone turnover during weight reduction in postmenopausal women.

Bone mobilization, lowering of bone mineral density (BMD), and osteoporotic fractures are recognized in postmenopausal women with weight loss. Because a high-calcium intake suppresses bone loss in peri- and postmenopausal women, the present randomized, double-blind, placebo-controlled study was designed to test the hypothesis that calcium supplementation prevents net bone mobilization and consequent bone mineral loss during voluntary weight reduction in obese postmenopausal women. Subjects were placed on a moderate energy-restricted diet and either calcium supplementation (1 g/day) or placebo for 6 months. Body weight, bone turnover markers (pyridinium cross-links), osteocalcin, and parathyroid hormone (PTH) were measured at treatment weeks 1-5, 7, 10, 13, 16, 20, and 25. Total body BMD, insulin-like growth factor, 25-hydroxyvitamin D, and sex hormone binding globulin (SHBG) were measured at baseline and week 25. The calcium supplemented (n = 15; age 60.9 +/- 9.4 years, body mass index [BMI] 33.2 +/- 4.6 kg/m2) and placebo (n = 16; age 55.8 +/- 8.3 years, BMI 32.9 +/- 4.5 kg/m2) groups lost similar amounts of weight over the study interval (10.2 +/- 5.3% vs. 10.0 +/- 5.2%) and both groups increased SHBG (p < 0.001). There was a statistical effect of calcium supplementation during weight loss to suppress pyridinium cross-links, osteocalcin, and PTH (p < 0.05, < 0.01, and < 0.05, respectively). Loss of BMD tended to be greater in the placebo group by 1.4% (p < 0.08) after weight loss. One gram per day calcium supplementation normalizes the increased calcium-PTH axis activity and the elevated bone turnover rate observed during moderate voluntary energy restriction in postmenopausal women.

Acute oxygen supplementation does not relieve the impairment of respiratory muscle strength in hypoxemic COPD.

STUDY OBJECTIVES: To verify whether hypoxemia affects respiratory muscle strength in the absence of malnutrition and whether such effect, if present, is reversible with an acute oxygen supplementation. DESIGN: Case series analysis, before-after trial. SETTING: Outpatient pneumology departments of two university hospitals. PATIENTS: One hundred twenty patients affected by COPD in stable conditions having actual to ideal body weight ratio of > or =90%. MEASUREMENTS AND RESULTS: Maximal inspiratory pressure (MIP) was measured at functional residual capacity level in the whole sample of subjects and during oxygen supplementation in 58 patients having a PaO2< or =60 mm Hg when breathing in room air. Predictors of MIP were assessed by a multivariate analysis. MIP values before and after oxygen supplementation were compared by a paired t test. MIP was independently correlated with FVC (p<0.001), PaO2 (p<0.01), and age (p<0.01). In the subgroup of hypoxemic patients, MIP values did not change significantly after oxygen supplementation (3.08+/-1.74 vs 3.03+/-1.91 kPa, t=0.43, not significant). CONCLUSIONS: Hypoxemia is an important negative correlate of MIP even in well-nourished COPD patients. Its effect is not reversible with an acute oxygen supplementation.

A case of pediatric systemic lupus erythematosus with early onset and unusual serologic and clinical findings.

The authors report on a case of Pediatric Systemic Lupus Erythematosus (SLE) in a female child aged 3 1/2 with a set of peculiar clinical and serologic characteristics; early onset of the disease, non-specific clinical signs, high serum levels of IgG and a clinical course characterized by the absence of renal neurological and articular involvement.

Endothelium-dependent vasorelaxation caused by various plant extracts.

In a previous study (Am J Physiol 1993;265: H774-8), we found that certain red wines and other grape products caused endothelium-dependent vasorelaxation. In the present study, aqueous extracts of a variety of vegetables, fruits, teas, nuts, herbs, and spices were tested for their endothelium-dependent relaxing ability in vitro. Rings of rat aorta, with or without an intact endothelium, were mounted in tissue baths, contracted with phenylephrine, and then exposed to diluted plant extracts. Many, but not all, extracts exhibited endothelium-dependent relaxations that were reversed by NG-monomethyl-L-arginine, a nitric oxide synthase inhibitor, which suggested involvement of nitric oxide, the endothelium-derived relaxing factor in the response. Furthermore, extracts that caused relaxation also increased tissue levels of cyclic GMP, the mediator of nitric oxide-induced vascular smooth-muscle relaxation. These results may lend further support to mounting evidence that plant foods contain compounds that, if absorbed intact and in sufficient quantities, could conceivably be beneficial in prevention of cardiovascular disease.

Experimental investigation of temperature gradients in the inner ear following argon laser exposure.

In microsurgery of the middle ear using argon laser, heat is produced on the sensorineural structures adjacent to the irradiated bones. Thermal gradients following laser applications have been measured by means of special thermocouples. The footplate was perforated by a 50 msec. ray applied both at 380 mWatt and at 460 mWatt. The maximum temperature increase registered in the labyrinthine spaces was respectively 2 degrees C. and 3.5 degrees C. Coagulation of the promontory mucosa was performed using 100 msec. impulses at 200 mWatt. At the end of a series of 12 applications the temperature increase at the level of the basal coil was 1.4 degrees C. From the above results the authors conclude that no damage is induced during laser microsurgery and that, considering the power and time values relative to impulses, the use of laser in routine clinical practice should be relatively safe.