Four pi calibration and modeling of a bare germanium detector in a cylindrical field source

In this paper we describe a 4π cylindrical field acquisition configuration surrounding a bare (unshielded, uncollimated) high purity germanium detector. We perform an efficiency calibration with a flexible planar source and model the configuration in the 4π cylindrical field. We then use exact calculus to model the flux on the cylindrical sides and end faces of the detector. We demonstrate that the model accurately represents the experimental detection efficiency compared to that of a point source and to Monte Carlo N-particle (MCNP) calculations of the flux. The model sums over the entire source surface area and the entire detector surface area including both faces and the detector's cylindrical sides. Agreement between the model and both experiment and the MCNP calculation is within 8%.     

Lateralized response to cortical injury in the rat: Interhemispheric interaction.

Two experiments, with 92 male Sprague-Dawley rats, examined the role of interhemispheric interaction in the production of spontaneous hyperactivity following right but not left frontal cortical suction lesions. Bilateral lesions, either simultaneous or left followed 1 wk later by right, led to spontaneous hyperactivity and bilateral depletions of cortical norepinephrine concentrations. Ss given corpus callosum sectioning as neonates and frontal cortical suction lesions as adults developed spontaneous hyperactivity only when the right hemisphere was injured. Data suggest that lateralized spontaneous hyperactivity as elicited by small suction lesions of the right hemisphere does not depend on interhemispheric release or interaction and that at least the cortical mechanism is in the right hemispere itself. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A search accelerated correct intensity Fourier transform microwave spectrometer with pulsed laser ablation source

The ablation of metal surfaces in the presence of a precursor gas produces reaction products which are often difficult to predict and highly dependent on ablation conditions. This article describes the successful development and implementation of a laser ablation source-equipped Fourier transform microwave spectrometer capable of observing 4 GHz regions of spectra in a single data acquisition event. The dramatically increased speed with which regions may be searched, when compared to other high resolution microwave techniques, allows the source conditions to be the prime variable in laser ablation microwave spectroscopic studies. A second feature of the technique is that observed spectral features have correct relative intensities. This is advantageous when assigning observed spectra. The study of two metal chlorides, AgCl and AuCl, illustrate the instrument's benefits.     

Say no to government control of patient care

Healthcare reform threatens to jeopardize the role of physicians in deciding what is appropriate care for their patients. Factors outside the doctor-patient relationship, such as a global budget and limited access, will exert increasing influence on the decision-making process, according to Dr Dewberry. In this commentary, he explores the roots of this dangerous trend and suggests that physicians take an uncompromising stance against it.