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Echoes of the sea around us—Human hopes in the balance
Earth’s human life-support system shows signs of failing. Human capacity to alter landscapes and the atmosphere is reaching catastrophic levels. Only the oceans seemed to be beyond control, but still they are not beyond human influence. Limited experience in protecting nature’s integrity, health, and resilience in seascapes offers the potential to reverse sliding global environmental conditions by providing realistic expectations, offering moral fortitude, stimulating imagination, and proffering hope. The ocean’s capacity to evoke human awe and inspiration may be sufficient to focusmankind on the global existential threats we face. It is now vital to heed Rachael Carson’s 1937 prescient observation “Against this cosmic background the lifetime of a particular plant or animal appears not as a drama complete in itself but only as a brief interlude in a panorama of endless change.” The world will keep spinning, whether people are able to enjoy the ride or not
Fiber optic vibration transducer and analyzer Patent
Fiber optic transducers for monitoring and analysis of vibration in aerospace vehicles and onboard equipmen
Systematic variation of the 12CO/13CO ratio as a function of star-formation rate surface density
We show that the12CO/13CO intensity ratio in nearby galaxies varies
systematically as a function of the star formation rate surface density and gas
surface density. The same effect is observed in different transitions, and in
the 12CO/C18O ratio, while the 13CO/C18O ratio appears to remain constant as a
function of the star formation rate surface density. We discuss the cause of
these variations, considering both changes in the physical state of the gas,
and chemical changes that lead to abundance variations. We used the observed
correlations with C18O to suggest that abundance variations are unlikely to be
causing the systematic trend observed with the star formation rate surface
density, and thus that the mean gas temperature and/or velocity dispersion are
systematically higher in higher star-formation rate surface density regions. We
present the best fitting relations between the star formation rate surface
density and the 12CO/13CO and 12CO/C18O ratios, and discuss how this effect can
help us predict CO isotope emission from galaxies across the known universe.Comment: 7 pages, 4 figures, accepted to MNRA
Fatigue failure load indicator
An indicator for recording the load at which a fatigue specimen breaks during the last cycle of a fatigue test is described. A load cell is attached to the specimen which is alternately subjected to tension and compression loads. The output of the load cell which is proportional to the load on the specimen is applied to the input of a peak detector. Each time the specimen is subjected to a compression load, means are provided for applying a positive voltage to the rest of the peak detector to reset it. During the last cycle of the tension load the peak detector measures the maximum load on the specimen. Means are provided for disconnecting the load cell from the peak detector when there is a failure in the specimen
Race and Policing: An Agenda for Action
This paper is organized into two parts -- Strategic Voice and Tactical Agency. Strategic Voice argues that problems of race in policing cannot be resolved by the police alone. Other people must help by understanding and ameliorating the social conditions that cause race to be associated with crime and hence become a dilemma for American policing. Rather than accepting these conditions as givens, police leaders with their powerful collective voice should actively call attention to what needs to be changed. Tactical Agency outlines what the police can do on their own initiative to deal with the operational dilemmas of race -- in the communities they serve and in their own organizations
Conformal Inflation Coupled to Matter
We formulate new conformal models of inflation and dark energy which
generalise the Higgs-Dilaton scenario. We embed these models in unimodular
gravity whose effect is to break scale invariance in the late time Universe. In
the early Universe, inflation occurs close to a maximum of both the scalar
potential and the scalar coupling to the Ricci scalar in the Jordan frame. At
late times, the dilaton, which decouples from the dynamics during inflation,
receives a potential term from unimodular gravity and leads to the acceleration
of the Universe. We address two central issues in this scenario. First we show
that the Damour-Polyalov mechanism, when non-relativistic matter is present
prior to the start of inflation, sets the initial conditions for inflation at
the maximum of the scalar potential. We then show that conformal invariance
implies that matter particles are not coupled to the dilaton in the late
Universe at the classical level. When fermions acquire masses at low energy,
scale invariance is broken and quantum corrections induce a coupling between
the dilaton and matter which is still small enough to evade the gravitational
constraints in the solar system.Comment: 24 page
Investigating jet and jet-like artefacts from Prehistoric Scotland: the National Museums Scotland project
Two-dimensional double-quantum spectroscopy: peak shapes as a sensitive probe of carrier interactions in quantum wells
We identify carrier scattering at densities below which it has previously
been observed in semiconductor quantum wells. These effects are evident in the
peakshapes of 2D double-quantum spectra, which change as a function of
excitation density. At high excitation densities (
carriers/,cm) we observe untilted peaks similar to those reported in
previous experiments. At low excitation densities (< carriers
cm) we observe narrower, tilted peaks. Using a simple simulation, we
show that tilted peak-shapes are expected in double-quantum spectra when
inhomogeneous broadening is much larger than homogeneous broadening, and that
fast pure-decoherence of the double-quantum coherence can obscure this peak
tilt. These results show that carrier interactions are important at lower
densities than previously expected, and that the `natural' double-quantum
peakshapes are hidden by carrier interactions at the excitation densities
typically used. Furthermore, these results demonstrate that analysis of 2D
peak-shapes in double-quantum spectroscopy provides an incisive tool for
identifying interactions at low excitation density
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