39,359 research outputs found
Botanical Latin: History, Grammar, Syntax, Terminology and Vocabulary. William T. Stearn. London and Edinburgh: Thomas Nelson and Sons, Ltd., 1966. xiv, 566pp.($14.75)
Excerpt: As W. T. Stearn reminds us in the preface to this attractive and welcome work, the realm of literature which a knowledge of botanical Latin opens to botanists is a strange barbarous place for classicists; invited into it as an interpreter, a good classical scholar may well feel like Alice meeting Humpty Dumpty through the looking-glass. The same perplexity is experienced by the entomologist; those of us educated in the Latin of Cicero and Pliny are ill equipped to name new species or even to translate Latin descriptions, as biological Latin developed long ago into a stylized form not easily conquered without a specific aid
Seven Illustrations from Maurice Sand\u27s Le Monde des Papillons (1867)
Excerpt: The tailpieces and rear cover illustration in this issue are six vignettes and the frontispiece from a popular nineteenth-century French work for beginning amateur lepidopterists, Maurice Sand\u27s Le monde des papillons (Paris, 1867). The frontispieces (our rear cover) depicts a melange of collecting equipment, including a ring net for aerial collecting, a folding sweeping net, an entomological satchel, various forceps, a pupa-digging spud, a collecting tin for larvae, a lantern, a collecting box into which adult specimens were pinned, and several items which have disappeared from our modern list of paraphernalia
Raman intensity as a probe of concentration near a crystal growing in solution
The feasibility of using Raman spectral scattering signals for measurements of concentration profiles near a crystal interface during growth or dissolution is discussed. With KH2PO4 (KDP) as a test material, optical multichannel analyzer (OMA) detection of a solute Raman vibrational band provided direct quantification of solute concentration with band intensity. The intersection of incident laser and Raman collection optics provided 3-D selective point measurements of the solution concentration field. Unlike many other techniques, the Raman band intensity is not sensitive to the typical temperature variations. Precision calibration of Raman intensity versus KDP concentration with less than 1 pct standard deviation error levels was demonstrated. A fiber optic, which sampled incident laser intensity and coupled it to the OMA, provided a fully synchronized monitor of fluctuations in laser power to correlate with observed Raman signals. With 1 W of laser power at the sample, good data statistics required eight repeated data collections at approximately 2.5 min collection. The accumulated time represents the concentration measurement time at one spatial location. Photomicroscopy documented a 30 micrometer diameter by 200 micrometer of laser Raman scattering region in the solution near the crystal surface. The laser beam was able to approach up to 25 micrometer from the crystal surface. However, a crystal surface reflected intensity contribution was weakly detectable. Nucleated microcrystals were seen in the crystal-growing solution. These microcrystals convect right up to the crystal surface and indicate no quiet diffusion region under normal gravity conditions. Translation of the solution cell with respect to the optics caused systematic intensity errors
A failsafe analysis using NASTRAN's piecewise linear analysis and a nine node linear crack element
A two-dimensional crack element was implemented into NASTRAN as a user dummy element and used to study failsafe characteristics of the C5A fuselage. The element is formulated from Reitsner's functional requiring that it satisfy compatability with the linear boundary displacement elements in NASTRAN. Its accuracy is demonstrated by analyzing for the stress intensity factors of two simple crack configurations for which there are classic solutions
Dark Matter In Disk Galaxies II: Density Profiles as Constraints on Feedback Scenarios
The disparity between the density profiles of galactic dark matter haloes
predicted by dark matter only cosmological simulations and those inferred from
rotation curve decomposition, the so-called cusp-core problem, suggests that
baryonic physics has an impact on dark matter density in the central regions of
galaxies. Feedback from black holes, supernovae and massive stars may each play
a role by removing matter from the centre of the galaxy on shorter timescales
than the dynamical time of the dark matter halo. Our goal in this paper is to
determine constraints on such feedback scenarios based on the observed
properties of a set of nearby galaxies.
Using a Markov Chain Monte Carlo (MCMC) analysis of galactic rotation curves,
via a method developed in a previous paper, we constrain density profiles and
an estimated minimum radius for baryon influence, , which we couple with a
feedback model to give an estimate of the fraction of matter within that radius
that must be expelled to produce the presently observed halo profile. We show
that in the case of the gas rich dwarf irregular galaxy DDO 154, an outflow
from a central source (e.g. a black hole or star forming region) could produce
sufficient feedback on the halo without removing the disk gas.
We examine the rotation curves of 8 galaxies taken from the THINGS data set
and determine constraints on the radial density profiles of their dark matter
haloes. For some of the galaxies, both cored haloes and cosmological cusps are excluded. These intermediate central slopes require
baryonic feedback to be finely tuned. We also find for galaxies which exhibit
extended cores in their haloes (e.g. NGC 925), the use of a split power-law
halo profile yields models without the unphysical, sharp features seen in
models based on the Einasto profile.Comment: 17 pages, 19 figures Submitted to MNRA
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Evaluating the transition of e-Government: A review of local authorities in England
The goal of e-Government is seen as a panacea for governmental authorities. The emerging needs of citizens, their inclusion and engagement in policy development, political and participatory processes have meant new perspectives on e-Government are required. This paper seeks to identify and evaluate the preparedness of 10 UK-based local authorities to transition from basic e-Government to a more sophisticated and integrated e-Government. A categorical assessment of e-Government characteristics is made and these authorities are ranked accordingly. Our findings reveal the majority of local authorities sampled had reached a high percentage of informational and transactional e-Government but few had reached the interactional level and none had achieved assimilation. This suggests that local authorities seem to have focused on basic e-Government services. There is a need now to forge ahead to integration and assimilation of e-Government in order to address the critical objectives of citizen inclusion and engagement, and alignment of institutional processes to provide an infrastructure for the transition to e-governance and e-knowledge
Work intensification and employment insecurity in professional work
Professional work is a category of employment that has traditionally been associated with high levels of worker autonomy, economic and social status. During the past decade, changes in customer expectations, government policy
and technology have generated pressures resulting in enhancement of the quality and efficiency of service provision, expansion in task requirements and a need for higher levels of discretion. In this sense, professional work has been upgraded. However, the changes have also led to a deterioration in the economic and social status of professional work, adversely impacting on the social and psychological well-being of professional workers. This paper
examines these developments in five professions including two established professions (lawyers and pharmacists), one aspiring profession (midwives) and two emerging professions (counselling psychologists and human resource managers). The empirical findings are based on a survey of 1270 professional workers conducted in 2000 and 2001
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