339 research outputs found
Contraceptive Efficacy of a Novel Intrauterine Device (IUD) in White-Tailed Deer
Overabundant white-tailed deer (Odocoileus virginianus) pose risks to property, health, and safety of human beings. Public concerns about lethal management can impair efforts to address these issues, particularly in urban settings. Several techniques developed for reducing reproductive output of deer have limited utility because they require repeated dosing to achieve permanent effect and face uncertain regulatory approval for use beyond experimentation. From 10 August 2006 through 30 December 2007, we evaluated the contraceptive efficacy of copper-containing intrauterine devices (IUDs) implanted trans-cervically in white-tailed deer at the E.S. George Reserve in Pinckney, Michigan. Intrauterine devices were implanted before (n = 9) and shortly after (n = 10) the breeding season. Post-breeding season IUD treatment was in conjunction with a 5 cm3 dose of 5 mg/ml prostaglandin F2α (PGF2α), delivered subcutaneously. Intrauterine devices reduced pregnancy rates when administered prior to breeding (P \u3c 0.001) and prevented pregnancy for up to 2 years (the duration of the study). Two of 8 does that received IUDs prior to the breeding season and survived to the end of the study became pregnant (due to loss of the implant) during the second year while all (n = 16) does without implants conceived. Cervical changes associated with early pregnancy made trans-cervical implantation after the breeding season challenging, and resulted in improperly placed IUDs in 2 treated does. The apparent expulsion of IUDs by pregnant does that received the combined treatment after breeding suggests IUD treatment should be limited to the pre-breeding season. Intrauterine devices show potential as a tool for small-scale deer population management via non-steroidal reproductive inhibition
Superconducting Gatemon Qubit based on a Proximitized Two-Dimensional Electron Gas
The coherent tunnelling of Cooper pairs across Josephson junctions (JJs)
generates a nonlinear inductance that is used extensively in quantum
information processors based on superconducting circuits, from setting qubit
transition frequencies and interqubit coupling strengths, to the gain of
parametric amplifiers for quantum-limited readout. The inductance is either set
by tailoring the metal-oxide dimensions of single JJs, or magnetically tuned by
parallelizing multiple JJs in superconducting quantum interference devices
(SQUIDs) with local current-biased flux lines. JJs based on
superconductor-semiconductor hybrids represent a tantalizing all-electric
alternative. The gatemon is a recently developed transmon variant which employs
locally gated nanowire (NW) superconductor-semiconductor JJs for qubit control.
Here, we go beyond proof-of-concept and demonstrate that semiconducting
channels etched from a wafer-scale two-dimensional electron gas (2DEG) are a
suitable platform for building a scalable gatemon-based quantum computer. We
show 2DEG gatemons meet the requirements by performing voltage-controlled
single qubit rotations and two-qubit swap operations. We measure qubit
coherence times up to ~2 us, limited by dielectric loss in the 2DEG host
substrate
Increased stress in Asiatic black bears relates to food limitation, crop raiding, and foraging beyond nature reserve boundaries in China
AbstractAsiatic black bears (Ursus thibetanus) are declining throughout much of their range. In China they are partially protected by a nature reserve system and rely heavily on hard mast as a food source prior to winter denning. Bears may compensate for mast shortages by raiding agricultural crops and killing livestock, mainly outside reserves where they are exposed to increased threats of poaching. We hypothesized that stress would vary with availability of high-quality refugia and fluctuations in mast abundance. We collected fecal samples from free-ranging bears in and around nature reserves in southwestern China, recorded habitat characteristics at each fecal sample location, and quantified abundance of hard mast. We used feces for genetic and endocrine analysis and identified 106 individuals. Feces collected outside reserves, or in agricultural fields within reserves, contained elevated concentrations of glucocorticoid metabolites compared to samples collected in intact, mast-producing forests within reserves. Relationships with habitat variables indicated that the hypothalamicâpituitaryâadrenal (HPA) axis of the Asiatic black bear is responsive to human activity, abundance of hard mast, extent of forest cover, and quality of diet. Our findings demonstrate biological reactions of a large mammal to variable forest quality, human threats, and foraging relative to boundaries of protected areas
Hierarchical Hough all-sky search for periodic gravitational waves in LIGO S5 data
We describe a new pipeline used to analyze the data from the fifth science
run (S5) of the LIGO detectors to search for continuous gravitational waves
from isolated spinning neutron stars. The method employed is based on the Hough
transform, which is a semi-coherent, computationally efficient, and robust
pattern recognition technique. The Hough transform is used to find signals in
the time-frequency plane of the data whose frequency evolution fits the pattern
produced by the Doppler shift imposed on the signal by the Earth's motion and
the pulsar's spin-down during the observation period. The main differences with
respect to previous Hough all-sky searches are described. These differences
include the use of a two-step hierarchical Hough search, analysis of
coincidences among the candidates produced in the first and second year of S5,
and veto strategies based on a test.Comment: 7 pages, 2 figures, Amaldi08 proceedings, submitted to JPC
A core outcome set for localised prostate cancer effectiveness trials
Objective:
To develop a core outcome set (COS) applicable for effectiveness trials of all interventions for localised prostate cancer.
Background:
Many treatments exist for localised prostate cancer, although it is unclear which offers the optimal therapeutic ratio. This is confounded by inconsistencies in the selection, definition, measurement and reporting of outcomes in clinical trials.
Subjects and methods:
A list of 79 outcomes was derived from a systematic review of published localised prostate cancer effectiveness studies and semi-structured interviews with 15 prostate cancer patients. A two-stage consensus process involving 118 patients and 56 international healthcare professionals (HCPs) (cancer specialist nurses, urological surgeons and oncologists) was undertaken, consisting of a three-round Delphi survey followed by a face-to-face consensus panel meeting of 13 HCPs and 8 patients.
Results:
The final COS included 19 outcomes. Twelve apply to all interventions: death from prostate cancer, death from any cause, local disease recurrence, distant disease recurrence/metastases, disease progression, need for salvage therapy, overall quality of life, stress urinary incontinence, urinary function, bowel function, faecal incontinence, sexual function. Seven were intervention-specific: perioperative deaths (surgery), positive surgical margin (surgery), thromboembolic disease (surgery), bothersome or symptomatic urethral or anastomotic stricture (surgery), need for curative treatment (active surveillance), treatment failure (ablative therapy), and side effects of hormonal therapy (hormone therapy). The UK-centric participants may limit the generalisability to other countries, but trialists should reason why the COS would not be applicable. The default position should not be that a COS developed in one country will automatically not be applicable elsewhere.
Conclusion:
We have established a COS for trials of effectiveness in localised prostate cancer, applicable across all interventions which should be measured in all localised prostate cancer effectiveness trials
Integration of selectively grown topological insulator nanoribbons in superconducting quantum circuits
We report on the precise integration of nm-scale topological insulator
Josephson junctions into mm-scale superconducting quantum circuits via
selective area epitaxy and local stencil lithography. By studying dielectric
losses of superconducting microwave resonators fabricated on top of our
selective area growth mask, we verify the compatibility of this in situ
technique with microwave applications. We probe the microwave response of
on-chip microwave cavities coupled to topological insulator-shunted
superconducting qubit devices and observe a power dependence that indicates
nonlinear qubit behaviour. Our method enables integration of complex networks
of topological insulator nanostructures into superconducting circuits, paving
the way for both novel voltage-controlled Josephson and topological qubits.Comment: 11 pages, 6 figure
A Catering Theory of Analyst Bias
We posit a theory that runs counter to how conventional wisdom thinks about analyst bias, that it is the result of distorted incentives by "the system" - especially upstream factors like the analysts' employers. We suggest that analysts are also heavily influenced by what investors believe, the purported victims of analyst bias. We adapt Mullainathan-Shleifer's theory of media bias to build a theory of how analysts cater to what investors believe. The theory also predicts that competition among analysts does not reduce their bias. We provide empirical support for this theory, using an enormous dataset built from over 6.5 million analyst estimates and 42.8 million observations on investor holdings, which we argue is a proxy for what they believe. We use a simultaneous-equations model for estimation, with instruments to rule out alternative interpretations of the direction of causality. For additional robustness, we investigate the time series of analyst bias and heterogeneity in investor beliefs from 1987 through 2003. Dickey-Fuller tests show that both have unit roots, but we establish that cointegration hold. Further, we employ a vector-autoregressive model to show Granger - causality between the two
UBVRI Light Curves of 44 Type Ia Supernovae
We present UBVRI photometry of 44 type-Ia supernovae (SN Ia) observed from
1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence
Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics. The
data set comprises 2190 observations and is the largest homogeneously observed
and reduced sample of SN Ia to date, nearly doubling the number of
well-observed, nearby SN Ia with published multicolor CCD light curves. The
large sample of U-band photometry is a unique addition, with important
connections to SN Ia observed at high redshift. The decline rate of SN Ia
U-band light curves correlates well with the decline rate in other bands, as
does the U-B color at maximum light. However, the U-band peak magnitudes show
an increased dispersion relative to other bands even after accounting for
extinction and decline rate, amounting to an additional ~40% intrinsic scatter
compared to B-band.Comment: 84 authors, 71 pages, 51 tables, 10 figures. Accepted for publication
in the Astronomical Journal. Version with high-res figures and electronic
data at http://astron.berkeley.edu/~saurabh/cfa2snIa
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