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The 1930s origins of California's Farmworker-Church alliance
In the 1930s, Social Gospel ministers in the Los Angeles area organized to help farmworkers in Southern California. The reformist pastors worked across class, denominational, and racial lines and transcended language barriers as they built urban, coastal support for immigrant farmworkers in interior valleys. In the end, they failed, largely because employers were able to use the Communist affiliations of the farmworker union leaders to Red-bait and intimidate the ministers. Only when a later generation of labor leaders distanced their movement from Communism and grounded it in Christian rhetoric and imagery would this religious-labor alliance achieve victory
Foreword
The land trust community and governments at all levels have become married to conservation easements as their land conservation tool of choice. The numbers speak for themselves: as of the date of this writing, there were reportedly 1,700 land trusts that have protected twelve million acres of land by use of conservation easements. The bulk of this growth both in conservation easements and the land trusts that deploy them has occurred since the 1980s when federal income tax incentives became more fully utilized by conservation easement donors. But the parties to this marriage have become complacent and inattentive in the face of a rapidly changing world resulting from global ecological catastrophes such as climate change and accelerated species extinction
The Invisible Forest: Conservation Easement Databases and the End of the Clandestine Conservation of Natural Lands
Olmsted talks about invisible forest refers to forest lands -- and, for that matter, any other land types -- protected by a perpetual conservation easement, the existence and location of which are concealed from the public, whether deliberately or because of the opaque nature of the easement process. Because easements, like other forms of deeds, must be recorded at the local land registry or recorder\u27s office, they can never be made undiscoverable. But, despite the efforts of some states and conservation organizations to compile conservation easement data for public consumption, there are few functional systems that comprehensively track and provide easy access to conservation easement data
Registered and antiregistered phase separation of mixed amphiphilic bilayers
We derive a mean-field free energy for the phase behaviour of coupled bilayer
leaflets, which is implicated in cellular processes and important to the design
of artificial membranes. Our model accounts for amphiphile-level structural
features, particularly hydrophobic mismatch, which promotes antiregistration
(AR), in competition with the `direct' trans-midplane coupling usually studied,
promoting registration (R). We show that the phase diagram of coupled leaflets
allows multiple \textit{metastable} coexistences, then illustrate the kinetic
implications with a detailed study of a bilayer of equimolar overall
composition. For approximate parameters estimated to apply to phospholipids,
equilibrium coexistence is typically registered, but metastable antiregistered
phases can be kinetically favoured by hydrophobic mismatch. Thus a bilayer in
the spinodal region can require nucleation to equilibrate, in a novel
manifestation of Ostwald's `rule of stages'. Our results provide a framework
for understanding disparate existing observations, elucidating a subtle
competition of couplings, and a key role for phase transition kinetics in
bilayer phase behaviour.Comment: Final authors' version. Important typo in Eq. A24 corrected. To
appear in Biophysical Journa
Instability and front propagation in laser-tweezed lipid bilayer tubules
We study the mechanism of the `pearling' instability seen recently in
experiments on lipid tubules under a local applied laser intensity. We argue
that the correct boundary conditions are fixed chemical potentials, or surface
tensions \Sigma, at the laser spot and the reservoir in contact with the
tubule. We support this with a microscopic picture which includes the intensity
profile of the laser beam, and show how this leads to a steady-state flow of
lipid along the surface and gradients in the local lipid concentration and
surface tension (or chemical potential). This leads to a natural explanation
for front propagation and makes several predictions based on the tubule length.
While most of the qualitative conclusions of previous studies remain the same,
the `ramped' control parameter (surface tension) implies several new
qualitative results. We also explore some of the consequences of front
propagation into a noisy (due to pre-existing thermal fluctuations) unstable
medium.Comment: 12 page latex + figures using epsf.sty to be published in Journal de
Physique II, January 199
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