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Transcription of Vernon Bailey's field notes for his 1909 trip to Lincoln Co., Coos Co., and Curry Co., Oregon with notes about biological survey records
The outstanding scientist, R.A. Fisher:His views on eugenics and race
R.A. Fisher was one of the greatest scientists of the 20th century (Fig. 1). He was a man of extraordinary ability and originality whose scientific contributions ranged over a very wide area of science, from biology through statistics to ideas on continental drift, and whose work has had a huge positive impact on human welfare. Not surprisingly, some of his large volume of work is not widely used or accepted at the current time, but his scientific brilliance has never been challenged. He was from an early age a supporter of certain eugenic ideas, and it is for this reason that he has been accused of being a racist and an advocate of forced sterilisation (Evans 2020). His promotion of eugenics has recently caused various organisations to remove his name from awards and dedications of buildings (Tarran 2020; Rothamsted Research 2020; Society for the Study of Evolution 2020; Gonville and Caius College 2020). A primary aim of this paper is to conduct a careful analysis of his own writings in these areas. Our purpose is neither to defend nor attack Fisher’s work in eugenics and views on race, but to present a careful account of their substance and nature.Publisher PDFPeer reviewe
Red giant collisions in the galactic centre
We simulate collisions involving red-giant stars in the centre of our galaxy.
Such encounters may explain the observed paucity of highly luminous red giants
within the central 0.2pc. The masses of the missing stars are likely to be in
the range 2 to 8 solar masses. Recent models of the galactic centre cluster's
density and velocity distributions are used to calculate two-body collision
rates. In particular we use stellar-evolution models to calculate the number of
collisions a star will have during different evolutionary phases. We find that
the number of two-body collisions per star is \lo 1 in the central 0.1 to 0.2
pc, depending strongly on the galactocentric radius. Using a 3D numerical
hydrodynamics code (SPH) we simulate encounters involving cluster stars of
various masses with 2 and 8 solar-mass red giants. The instantaneous mass loss
in such collisions is rarely enough to destroy either giant. A fraction of the
collisions do, however, lead to the formation of common envelope systems where
the impactor and giant's core are enshrouded by the envelope of the giant. Such
systems may evolve to expel the envelope, leaving a tight binary; the original
giant is destroyed. The fraction of collisions that produce common envelope
systems is sensitive to the local velocity dispersion and hence galactocentric
radius. Using our collision-rate calculations we compute the time-scales for a
giant star to suffer such a collision within the galactic centre. These
time-scales are >10^{9-10}years and so are longer than the lifetimes of stars
more-massive than 2 solar masses. Thus the observed paucity of luminous giants
is unlikely to be due to the formation of common envelope systems as a result
of two-body encounters involving giant stars.Comment: 10 pages, 11 figures, MNRAS (in press
Effects of Shielding on Properties of Eddy Current Probes with Ferrite Cup Cores
In eddy current inspection the ability to detect small defects depends on the sensitivity of the system and on the relative sizes of the probe and the defect. To detect defects on the opposite surface the probe radius should be at least as great as the thickness of the material. This limits the sensitivity to small defects that can be achieved by decreasing the probe size. Assuming the instrumentation is a given, further sensitivity can be achieved by improving the sensitivity of the probe itself.</p
加令と膵 第1編 加令に伴う膵外分泌機能の変化 Pancreozymin secretin testによる年令層別生理値の設定 第2編 加令に伴う膵管造影像の変化 第3編 機能と形態から見た膵の老化
The Electric Dipole Moment of the Muon in a Two Higgs Doublet Model
The electric dipole moment of the muon () is evaluated in a two Higgs
doublet model with a softly broken discrete symmetry. The leading contributions
from both one loop and two loop diagrams are considered. For close to one, contributions from two loop diagrams involving the
quark and the boson dominate; while for \tan\beta \agt 10,
contributions from two loop diagrams involving the quark and the
lepton are dominant. In these two regions, . For
8 \agt \tan\beta \agt 4, significant cancellation occurs among the
contributions from two loop diagrams and the one loop contribution dominates
for . For \tan\beta \agt 15, the calculated can be
close to the reach of a recently proposed experiment at the Brookhaven National
Laboratory.Comment: 16 pages, REVTeX, 7 Postscript Figures, To be published in Physical
Review
Changing Politics: Towards a New Democracy
In October 2014 the PSA joint-funded a Consultation event ‘Changing Politics – Towards a New Democracy’ with St. George’s House. The Chair of the PSA, Professor Matthew Flinders, chaired the event which brought together participants from a range of fields (including academics, think tankers and practitioners in several policy areas). Today, St. George’s House has published a report which highlights the main themes emerging from the discussion as well as some conclusions and recommendations. It identifies several areas where changes are urgently needed to reinvigorate democracy. The report concludes that to fully succeed in addressing the growth of political apathy and disengagement, parties and leaders must forget their differences and join citizens, academics, charities and others to address this problem with all available energy and resources
Earthquakes: from chemical alteration to mechanical rupture
In the standard rebound theory of earthquakes, elastic deformation energy is
progressively stored in the crust until a threshold is reached at which it is
suddenly released in an earthquake. We review three important paradoxes, the
strain paradox, the stress paradox and the heat flow paradox, that are
difficult to account for in this picture, either individually or when taken
together. Resolutions of these paradoxes usually call for additional
assumptions on the nature of the rupture process (such as novel modes of
deformations and ruptures) prior to and/or during an earthquake, on the nature
of the fault and on the effect of trapped fluids within the crust at
seismogenic depths. We review the evidence for the essential importance of
water and its interaction with the modes of deformations. Water is usually seen
to have mainly the mechanical effect of decreasing the normal lithostatic
stress in the fault core on one hand and to weaken rock materials via
hydrolytic weakening and stress corrosion on the other hand. We also review the
evidences that water plays a major role in the alteration of minerals subjected
to finite strains into other structures in out-of-equilibrium conditions. This
suggests novel exciting routes to understand what is an earthquake, that
requires to develop a truly multidisciplinary approach involving mineral
chemistry, geology, rupture mechanics and statistical physics.Comment: 44 pages, 1 figures, submitted to Physics Report
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