Toward effective and ethical drug abuse prevention policies: The case against indiscriminate drug testing

For an increasing breadth of organizational domains, a negative illicit drug screen result has become the final and paramount criterion for admission and/or continuing participation. Such a policy is vigorously promoted to the private sector by government and vendors of testing services as an inexpensive and vital tool for suppressing drug abuse. This policy, however, can been shown to be at once empirically unwarranted, methodologically dubious, constitutionally impermissible, and ethically unsustainable. Reducing the harm attributable to illicit intoxication is a legitimate and worthy social goal. The ends, however, cannot justify such means of indiscriminate and intrusive surveillance

Size Regulation within the Germline of the Developing Egg Chamber

The relationship between the size of a cell and the size of its intracellular structures must be precisely regulated for proper development and functioning of the mature organism; however, the mechanisms that establish and maintain this relationship are not known. Much of the work on organelle size scaling has focused on individual cells or organelles, with some looking at how size scaling is maintained during development. However, it is not known whether the size of multiple organelles is coordinately regulated, and how cell size and organelle size are regulated within a syncytium or group of connected cells. Because many cell types exist within a syncytium, understanding size scaling in this context is important. We have used the developing fruit fly egg chamber as a model system to study the size relationship between multiple structures within the germline syncytium throughout oogenesis. The developing egg chamber contains a cluster of 16 germ cells connected by intercellular bridges, or ring canals. It has been observed that the size of the germline ring canals exhibits spatial variation with the smallest ring canals at the anterior of the egg chamber and the largest ring canals at the posterior near the oocyte. Recent work has also confirmed that nurse cells and their nuclei show a similar size distribution within the germline. Therefore, it is interesting to consider whether the size of these structures may be coordinately regulated, and whether altering the size of one structure (either throughout the germline or clonally) would impact the size of the other structure. We have used a combination of RNAi (Pendulin, Dacapo, or Ctf4), overexpression (Pendulin) and mosaic analysis (myc and arpC1) to try to alter either nuclear size or ring canal size in some or all cells within the germline. We used Fiji to measure the diameter of the ring canals, the size of the nurse cell nuclei (which has been used as a proxy for cell size), and the overall dimensions of the egg chamber. Preliminary data suggest that altering nuclear size within the entire germline does impact ring canal size, and that in mosaic tissue, there is typically a correlation between cell size, nuclear size, and ring canal size. In the future, we hope to further explore whether the size of these structures is coordinately regulated, and if so, to identify the underlying mechanisms that are involved

On deformation of electron holes in phase space

This Letter shows that for particularly shaped background particle distributions momentum exchange between phase space holes and the distribution causes acceleration of the holes along the magnetic field. In the particular case of a non-symmetric ring distribution (ring with loss cone) this acceleration is nonuniform in phase space being weaker at larger perpendicular velocities thus causing deformation of the hole in phase space.Comment: Original MS in EPL style, 1 Figur

Spectral and spatial observations of microwave spikes and zebra structure in the short radio burst of May 29, 2003

The unusual radio burst of May 29, 2003 connected with the M1.5 flare in AR 10368 has been analyzed. It was observed by the Solar Broadband Radio Spectrometer (SBRS/Huairou station, Beijing) in the 5.2-7.6 GHz range. It proved to be only the third case of a neat zebra structure appearing among all observations at such high frequencies. Despite the short duration of the burst (25 s), it provided a wealth of data for studying the superfine structure with millisecond resolution (5 ms). We localize the site of emission sources in the flare region, estimate plasma parameters in the generation sites, and suggest applicable mechanisms for interpretating spikes and zebra-structure generation. Positions of radio bursts were obtained by the Siberian Solar Radio Telescope (SSRT) (5.7 GHz) and Nobeyama radioheliograph (NoRH) (17 GHz). The sources in intensity gravitated to tops of short loops at 17 GHz, and to long loops at 5.7 GHz. Short pulses at 17 GHz (with a temporal resolution of 100 ms) are registered in the R-polarized source over the N-magnetic polarity (extraordinary mode). Dynamic spectra show that all the emission comprised millisecond pulses (spikes) of 5-10 ms duration in the instantaneous band of 70 to 100 MHz, forming the superfine structure of different bursts, essentially in the form of fast or slow-drift fibers and various zebra-structure stripes. Five scales of zebra structures have been singled out. As the main mechanism for generating spikes (as the initial emission) we suggest the coalescence of plasma waves with whistlers in the pulse regime of interaction between whistlers and ion-sound waves. In this case one can explain the appearance of fibers and sporadic zebra-structure stripes exhibiting the frequency splitting.Comment: 11 pages, 5 figures, in press; A&A 201