An analysis of the atmospheric propagation of underground-explosion-generated infrasonic waves based on the equations of fluid dynamics: Ground recordings.

An investigation on the propagation of underground-explosion-generated infrasonic waves is carried out via numerical simulations of the equations of fluid dynamics. More specifically, the continuity, momentum, and energy conservation equations are solved along with the Herzfeld-Rice equations in order to take into account the effects of vibrational relaxation phenomena. The radiation of acoustic energy by the ground motion caused by underground explosions is initiated by enforcing the equality, at ground level, between the component of the air velocity normal to the Earth's surface and the normal velocity of the ground layer. The velocity of the ground layer is defined semi-empirically as a function of the depth of burial and of the yield. The effects of the depth and of the source energy on the signals recorded in the epicentral zone are first discussed. The tropospheric and stratospheric infrasonic phases traveling at a long-range are then analyzed and explained. Synthesized ground waveforms are finally discussed and compared to those recorded at the I45RU station of the International Monitoring System after the 2013 North-Korean test. Good agreement is found between numerical results and experimental data, which motivates the use of infrasound technologies alongside seismic techniques for the characterization of underground explosions.

The New Stories/New Cultures after-school enrichment program: a direct cultural intervention.

This article describes the organization, curriculum, and outcomes for New Stories/New Cultures, an activity-based program for after-school enrichment in five schools in the low-income neighborhood near a major American university. The program encourages students (70% Hispanic-American, 30% African-American) to experience themselves as producers of culture, not just as consumers. Its methods include (a) creative team use of video equipment and other expressive media and (b) lessons about media literacy (i.e., making critical choices about images and activities depicted in popular culture and commercials). Outcome measures with the cohort of fifth and sixth graders support the programs occupation-based philosophy. They show that students are more likely to experience themselves as building skills when engaged in activities that are both challenging and enjoyable. The students reported greatest engagement and enjoyment in activities that were creative, team-based, and involving media production. These same activities were correlated with increased self-esteem. The term direct cultural intervention is used to describe the application of occupational principles and critical perspectives to provide a population with conceptual tools and skills for interpreting and successfully navigating the social world.

Pinacidil, a new vasodilator, in the treatment of mild to moderate essential hypertension.

Twenty three patients with essential hypertension who were uncontrolled on diuretic and/or beta-receptor antagonist therapy were treated additionally with the vasodilator, pinacidil, in an open study. Significant reduction in mean blood pressure was achieved. Supine and erect systolic and diastolic blood pressure fell by 44/25 mmHg and 37/24 mmHg respectively over the study period of 12 weeks. Side-effects such as dizziness, headache, facial flushing and mild oedema were experienced by 10 patients during the study, all of which were mild and transient and did not require withdrawal from pinacidil therapy. Pinacidil is an effective and well tolerated agent in the treatment of essential hypertension.

Pharmacokinetics and bioavailability of pinacidil capsules in human volunteers.

Pinacidil is a new and potent vasodilator, which has recently been used in the treatment of various forms of hypertension. In this study pharmacokinetic parameters were determined following administration of intravenous (0.2 mg/kg) and capsule (12.5 mg) formulations of pinacidil to twelve healthy volunteers. The serum half-life (t1/2) and volume of distribution (Vd) of pinacidil were 2.04 +/- 0.40 h and 1.4 +/- 0.4 l/kg respectively, while the elimination rate constant (k el) was 0.34 +/- 0.07 h-1. The mean bioavailability of pinacidil (capsule formulation) was 57% +/- 16 S.D. Mild side-effects such as dizziness, headache and fatigue were noted in two volunteers following intravenous administration of pinacidil, while no side-effects were reported with the oral formulation.