The Participation of Junior High School Boys in Competitive Athletics

The problem of this study was to gather information concerning interschool athletics. The chief purposes of this study were to: (1) Collect and summarize the literature written by the medical profession; (2) Collect and summarize the literature written by the educational profession; and (3) To present the research written by those involved, so that people concerned with the problem might make a better judgement on the advisability of interschool athletics at the junior high level

Spin correlations and Dzyaloshinskii-Moriya interaction in Cs2_2CuCl4_4

We report on electron spin resonance (ESR) studies of the spin relaxation in Cs$_2$CuCl$_4$. The main source of the ESR linewidth at temperatures $T \leq 150$ K is attributed to the uniform Dzyaloshinskii-Moriya interaction. The vector components of the Dzyaloshinskii-Moriya interaction are determined from the angular dependence of the ESR spectra using a high-temperature approximation. Both the angular and temperature dependence of the ESR linewidth have been analyzed using a self-consistent quantum-mechanical approach. In addition analytical expressions based on a quasi-classical picture for spin fluctuations are derived, which show good agreement with the quantum-approach for temperatures $T \geq 2J/k_{\rm B} \approx 15$ K. A small modulation of the ESR linewidth observed in the $ac$-plane is attributed to the anisotropic Zeeman interaction, which reflects the two magnetically nonequivalent Cu positions

A 15-year-old girl with a large pericardial effusion

Pericarditis is a rare manifestation of tuberculosis and can be fatal. We describe a 15-year-old girl admitted for a large pericardial effusion. Subxiphoid pericardial biopsy was performed. Biopsy samples were positive for M. tuberculosis DNA by PCR, which confirmed the diagnosis of tuberculous pericarditis

Collectieve versus individuele contracten voor natuurbeheer

In dit onderzoek staat de vraag centraal of collectieve contracten in vergelijking met individuele contracten efficiënter zijn en/of een grotere ecologische effectiviteit hebben. Daarbij is bijzondere aandacht gegeven aan de rol die agrarische natuurverenigingen kunnen spele