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Invaders for sale: the ongoing spread of invasive species by the plant trade industry
The sale of ornamental nonnative plants is a primary pathway of invasive plant introduction into the US. As a result, many nonnative plants have been identified as noxious weeds by federal and state governments, or as problematic invasive plants by agencies and nonprofit organizations. However, it is unclear whether identifying a species as invasive has curtailed its sale as an ornamental. Using the Google search engine and a database of nursery catalogs, we found that 61% of 1285 plant species identified as invasive in the US remain available through the plant trade, including 50% of state-regulated species and 20% of federal noxious weeds. Vendors offering invasive plants were located in all lower 48 states. The widespread availability of invasive plants in the US is likely a symptom of disjointed state regulations that fail to protect ecosystems and economies. Regional regulation coupled with outreach to growers and consumers is needed to reduce the ongoing propagation of invasive plants in the US
A -adic RanSaC algorithm for stereo vision using Hensel lifting
A -adic variation of the Ran(dom) Sa(mple) C(onsensus) method for solving
the relative pose problem in stereo vision is developped. From two 2-adically
encoded images a random sample of five pairs of corresponding points is taken,
and the equations for the essential matrix are solved by lifting solutions
modulo 2 to the 2-adic integers. A recently devised -adic hierarchical
classification algorithm imitating the known LBG quantisation method classifies
the solutions for all the samples after having determined the number of
clusters using the known intra-inter validity of clusterings. In the successful
case, a cluster ranking will determine the cluster containing a 2-adic
approximation to the "true" solution of the problem.Comment: 15 pages; typos removed, abstract changed, computation error remove
Frequency down conversion through Bose condensation of light
We propose an experimental set up allowing to convert an input light of
wavelengths about into an output light of a lower frequency. The
basic principle of operating relies on the nonlinear optical properties
exhibited by a microcavity filled with glass. The light inside this material
behaves like a 2D interacting Bose gas susceptible to thermalise and create a
quasi-condensate. Extension of this setup to a photonic bandgap material (fiber
grating) allows the light to behave like a 3D Bose gas leading, after
thermalisation, to the formation of a Bose condensate. Theoretical estimations
show that a conversion of into is achieved with an input
pulse of about with a peak power of , using a fiber grating
containing an integrated cavity of size about .Comment: 4 pages, 1 figure
Exploring How Counselor Education Programs Support Site Supervisors
CACREP standards require counselor education programs to provide site supervisors with orientation, consultation, and professional development opportunities (PD). Using a nonexperimental descriptive design, we collected data from a national sample of CACREP-accredited programs (N=46, 13.3% response rate) via an online descriptive survey to explore how programs provide such opportunities to site supervisors. The survey contained open-ended and multiple-choice items addressing orientation, consultation, PD, and participants’ opinions on how their program addressed the three domains. We analyzed numerical data using descriptive statistics and open-ended responses using content analysis. We found that most programs offered orientation, consultation, and PD, though site supervisor engagement and methods of implementation varied considerably. Implications for research and practice are discussed in light of the findings
Amplification of High-Order Rainbows of a Cylinder with an Elliptical Cross Section
The intensity of high-order rainbows for normally incident light and certain rotation angles of a cylinder with an elliptical cross section is greatly amplified with respect to the intensity for a circular cross-sectional cylinder. The amplification is due to a number of the internal reflections occurring past the critical angle for total internal reflection, and the effect is especially strong for odd-order rainbows, beginning with the third order. Experimentally, the fourth-and the fifth-order rainbows of a nearly elliptical cross-sectional glass rod were observed and analyzed. (C) 1998 Optical Society of America
Sarcoidosis: Hiding in Plain Sight
Introduction: Sarcoidosis is a systemic disease that can masquerade as many conditions. Due to its often patchy distribution, myocardial biopsy is only ∼30% sensitive. Herein we present a case of sarcoidosis diagnosed from an extra-cardiac biopsy years after the onset of cardiomyopathy.
Case Report: A 54 year old man initially presented with dyspnea and fatigue due to new onset HFrEF of 20%. He had a significant family history of SCD. His workup revealed non-obstructive CAD, a myxomatous mitral valve with bileaflet prolapse and moderate regurgitation, and a cystic structure attached to the tricuspid valve. Given his frequent ventricular ectopy, he was discharged on guideline therapy for HFrEF and a wearable cardioverter defibrillator. Genetic testing for dilated cardiomyopathies revealed EYA4 and TTN variants of unknown significance. A cardiac MRI a few months later demonstrated no abnormal late gadolinium enhancement and persistent systolic dysfunction, so he underwent AICD implant. His course was further complicated by recurrent admissions for supraventricular and ventricular tachyarrhythmias. A cardiopulmonary exercise stress test demonstrated low-risk results. Further evaluation noted prolonged AV conduction. A RHC revealed mild post-capillary pulmonary hypertension and a mildly decreased cardiac index at 2.01 L/min/m2. Months later, he underwent CRT-D upgrade. He started improving functionally until he developed left eyelid swelling, initially thought to be lymphoma. An orbital biopsy revealed non-caseating granulomas. A PET/CT demonstrated FDG uptake within subcarinal lymph nodes but no cardiac uptake. Initially he declined immunomodulatory therapy, but as his symptoms worsened, he started corticosteroids and transitioned to mycophenolate mofetil due to intolerance of methotrexate. Due to disease progression on repeat FDG-PET, he was switched to infliximab. The diagnosis of sarcoidosis can be difficult due to its variable presentation, including heart block, heart failure, ventricular arrhythmias and sudden cardiac death. Cardiac involvement occurs in 25% of cases. Our case was complicated by a cMRI that was negative for cardiac involvement, which emphasizes the importance of complimentary inflammatory imaging with FDG-PET. A multidisciplinary approach is needed that engages sarcoid specialists for earlier diagnosis to ensure rapid initiation of therapy to reduce end-organ dysfunction
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