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A Policy Analysis of Large Carnivore Responses to Habitat Fragmentation and Human – Carnivore Conflicts in the High Divide
The Northern Rockies contain upwards of 10 million acres of the most pristine land left in the Lower 48 states. A continuous landscape is necessary to preserve the function and beauty of the ecosystems found in this area. The High Divide is an essential wildlife corridor that enables the movement of organisms to and from three of these major ecosystems in the Northern Rockies. In recent years, residential development has increased fragmentation of the High Divide, impeding animal movement through the area. This restriction is especially significant for gray wolves (Canis lupus) and grizzly bears (Ursus arctos horribilis) as they are apex predators that have large movement patterns and major roles in ecosystem function and biodiversity. This project analyzes the issue by mapping predator ranges and residential development data using ArcGIS to visualize the extent of overlap. It then investigates the effectiveness of current and alternative management schemes through a policy analysis to determine what strategies are most effective in conserving wolves and grizzly bears with minimal landscape fragmentation while also protecting people and their property
A case of chronic myelogenous leukemia in pregnancy characterized by a complex translocation t(9;22;11)(q34;q11.2;q13)
The management of chronic myelogenous leukemia during pregnancy requires balancing the well-being of the mother with that of the fetus. We report a case of a 26-year-old lady who was diagnosed with chronic myelogenous leukemia (CML) at 15 weeks gestation and who had an atypical chromosome t(9;22;11) (q34;q11.2;q13) translocation. She was observed through the remainder of the pregnancy and the disease remained stable; she delivered a normal boy. Treatment with imatinib mesylate was initiated shortly after delivery and she went into molecular complete remission. We discuss the course of the disease and suggest guidelines for managing pregnancy with respect to the currently available agents imatinib, dasatinib and nilotinib
Social Venture Business Model Archetypes: Five Vehicles for Creating Economic and Social Value
Social ventures balance the economic and social dimensions of value creation to alleviate the problems created by shared collective issues. While much is known about economic value creation in conventional firms, little empirical work has focused on social ventures. As the number of social entrepreneurs continues to increase, the challenge of creating both economic and social value has emerged as an important research topic. In this article, we examine 124 social ventures from around the world to gain insight into ways social ventures pursue economic and social value creation. Five social venture business model archetypes emerge from the data. We conclude with implications for both theory and practice, and promising areas for future research
HadISD: a quality-controlled global synoptic report database for selected variables at long-term stations from 1973--2011
[Abridged] This paper describes the creation of HadISD: an automatically
quality-controlled synoptic resolution dataset of temperature, dewpoint
temperature, sea-level pressure, wind speed, wind direction and cloud cover
from global weather stations for 1973--2011. The full dataset consists of over
6000 stations, with 3427 long-term stations deemed to have sufficient sampling
and quality for climate applications requiring sub-daily resolution. As with
other surface datasets, coverage is heavily skewed towards Northern Hemisphere
mid-latitudes.
The dataset is constructed from a large pre-existing ASCII flatfile data bank
that represents over a decade of substantial effort at data retrieval,
reformatting and provision. These raw data have had varying levels of quality
control applied to them by individual data providers. The work proceeded in
several steps: merging stations with multiple reporting identifiers;
reformatting to netCDF; quality control; and then filtering to form a final
dataset. Particular attention has been paid to maintaining true extreme values
where possible within an automated, objective process. Detailed validation has
been performed on a subset of global stations and also on UK data using known
extreme events to help finalise the QC tests. Further validation was performed
on a selection of extreme events world-wide (Hurricane Katrina in 2005, the
cold snap in Alaska in 1989 and heat waves in SE Australia in 2009). Although
the filtering has removed the poorest station records, no attempt has been made
to homogenise the data thus far. Hence non-climatic, time-varying errors may
still exist in many of the individual station records and care is needed in
inferring long-term trends from these data.
A version-control system has been constructed for this dataset to allow for
the clear documentation of any updates and corrections in the future.Comment: Published in Climate of the Past, www.clim-past.net/8/1649/2012/. 31
pages, 23 figures, 9 pages. For data see
http://www.metoffice.gov.uk/hadobs/hadis
Voltage-dependent behavior of a "ball-and-chain" gramicidin channel
This is the published version. Copyright 1997 by Elsevier.The channel-forming properties of two analogs of gramicidin, gramicidin-ethylenediamine (gram-EDA), and gramicidin-N,N-dimethylethylenediamine (gram-DMEDA) were studied in planar lipid bilayers, using protons as the permeant ion. These peptides have positively charged amino groups tethered to their C-terminal ends via a linker containing a carbamate group. Gram-DMEDA has two extra methyl groups attached to the terminal amino group, making it a bulkier derivative. The carbamate groups undergo thermal cis-trans isomerization on the 10–100-ms time scale. The conductance behavior of gram-EDA is found to be markedly voltage dependent, whereas the behavior of gram-DMEDA is not. In addition, voltage affects the cis-trans ratios of the carbamate groups of gram-EDA, but not those of gram-DMEDA. A model is proposed to account for these observations, in which voltage can promote the binding of the terminal amino group of gram-EDA to the pore in a "ball-and-chain" fashion. The bulkiness of the gram-DMEDA derivative prevents this binding
A near-infrared spectroscopic screening of the red giant populations in omega Centauri
Near-infrared spectra of 21 giants in omega Centauri, spanning the whole
range of metallicities observed in this cluster, are presented. This work is
part of a coordinated photometric and spectroscopic campaign in the optical and
in the infrared, aimed at studying the complex stellar population of omega
Centauri and understanding its formation and chemical evolution. By analyzing
the several CO and OH molecular bands and atomic lines in the spectra of the
selected giants, metal abundances and abundance ratios have been obtained. The
existence of three major metallicity regimes at [Fe/H]=-1.6, -1.2 and
[Fe/H]<-0.5 has been confirmed. The most metal-rich stars in our sample show a
lower (if any) alpha-enhancement when compared to the more metal-poor
components, suggesting that they should have formed in a medium significantly
polluted by type Ia supernova ejecta. Isotopic carbon abundances have been also
inferred, providing an average 13C/12C=4, which clearly indicates that
extra-mixing processes occurred in the stellar interiors during the ascent on
the Red Giant Branch.Comment: 22 pages, 7 .ps figures. aastex. Accepted for pubilcation in the
Astrophysical Journa
Interaction-based quantum metrology showing scaling beyond the Heisenberg limit
Quantum metrology studies the use of entanglement and other quantum resources
to improve precision measurement. An interferometer using N independent
particles to measure a parameter X can achieve at best the "standard quantum
limit" (SQL) of sensitivity {\delta}X \propto N^{-1/2}. The same interferometer
using N entangled particles can achieve in principle the "Heisenberg limit"
{\delta}X \propto N^{-1}, using exotic states. Recent theoretical work argues
that interactions among particles may be a valuable resource for quantum
metrology, allowing scaling beyond the Heisenberg limit. Specifically, a
k-particle interaction will produce sensitivity {\delta}X \propto N^{-k} with
appropriate entangled states and {\delta}X \propto N^{-(k-1/2)} even without
entanglement. Here we demonstrate this "super-Heisenberg" scaling in a
nonlinear, non-destructive measurement of the magnetisation of an atomic
ensemble. We use fast optical nonlinearities to generate a pairwise
photon-photon interaction (k = 2) while preserving quantum-noise-limited
performance, to produce {\delta}X \propto N^{-3/2}. We observe super-Heisenberg
scaling over two orders of magnitude in N, limited at large N by higher-order
nonlinear effects, in good agreement with theory. For a measurement of limited
duration, super-Heisenberg scaling allows the nonlinear measurement to overtake
in sensitivity a comparable linear measurement with the same number of photons.
In other scenarios, however, higher-order nonlinearities prevent this crossover
from occurring, reflecting the subtle relationship of scaling to sensitivity in
nonlinear systems. This work shows that inter-particle interactions can improve
sensitivity in a quantum-limited measurement, and introduces a fundamentally
new resource for quantum metrology
Multiple populations in Omega Centauri: a cluster analysis of spectroscopic data
Omega Cen is composed of several stellar populations. Their history might
allow us to reconstruct the evolution of this complex object. We performed a
statistical cluster analysis on the large data set provided by Johnson and
Pilachowski (2010). Stars in Omega Cen divide into three main groups. The
metal-poor group includes about a third of the total. It shows a moderate O-Na
anticorrelation, and similarly to other clusters, the O-poor second generation
stars are more centrally concentrated than the O-rich first generation ones.
This whole population is La-poor, with a pattern of abundances for n-capture
elements which is very close to a scaled r-process one. The metal-intermediate
group includes the majority of the cluster stars. This is a much more complex
population, with an internal spread in the abundances of most elements. It
shows an extreme O-Na anticorrelation, with a very numerous population of
extremely O-poor and He-rich second generation stars. This second generation is
very centrally concentrated. This whole population is La-rich, with a pattern
of the abundances of n-capture elements that shows a strong contribution by the
s-process. The spread in metallicity within this metal-intermediate population
is not very large, and we might attribute it either to non uniformities of an
originally very extended star forming region, or to some ability to retain a
fraction of the ejecta of the core collapse SNe that exploded first, or both.
As previously noticed, the metal-rich group has an Na-O correlation, rather
than anticorrelation. There is evidence for the contribution of both massive
stars ending their life as core-collapse SNe, and intermediate/low mass stars,
producing the s-capture elements. Kinematics of this population suggests that
it formed within the cluster rather than being accreted.Comment: Accepted for publication in Astronomy and Astrophysic
Remnant Fermi surface in the presence of an underlying instability in layered 1T-TaS_2
We report high resolution angle-scanned photoemission and Fermi surface (FS)
mapping experiments on the layered transition-metal dichalcogenide 1T-TaS_2 in
the quasi commensurate (QC) and the commensurate (C) charge-density-wave (CDW)
phase. Instead of a nesting induced partially removed FS in the CDW phase we
find a pseudogap over large portions of the FS. This remnant FS exhibits the
symmetry of the one-particle normal state FS even when passing from the
QC-phase to the C-phase. Possibly, this Mott localization induced transition
represents the underlying instability responsible for the pseudogapped FS
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