AVIRIS ground data-processing system

The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has been under development at JPL for the past four years. During this time, a dedicated ground data-processing system has been designed and implemented to store and process the large amounts of data expected. This paper reviews the objectives of this ground data-processing system and describes the hardware. An outline of the data flow through the system is given, and the software and incorporated algorithms developed specifically for the systematic processing of AVIRIS data are described

Discovery Learning: Development of a Unique Active Learning Environment for Introductory Chemistry

It is well established that active learning results in greater gains in student conceptual knowledge and retention compared to traditional modes of learning.  However, active learning can be very difficult to implement in a large-enrollment course due to various course and institutional barriers.  Herein, we describe the development and implementation of Discovery Learning, a novel active learning discussion/recitation for a large enrollment general chemistry course.  Drawing on the very successful cooperative learning pedagogies Process-Oriented Guided Inquiry Learning (POGIL) and Student-Centered Active Learning Environment with Upside-down Pedagogies (SCALE_UP), Discovery Learning involves students working in self-managed teams on inquiry problems in a unique learning environment, the Chemistry Discovery Center.  In this case study, we will describe the design and implementation of Discovery Learning and report data on its successes, which include increased student performance and retention

Evidence for Dynamical Changes in a Transitional Protoplanetary Disk with Mid-infrared Variability

We present multi-epoch Spitzer Space Telescope observations of the transitional disk LRLL 31 in the 2-3 Myr-old star forming region IC 348. Our measurements show remarkable mid-infrared variability on timescales as short as one week. The infrared continuum emission exhibits systematic wavelength-dependent changes that suggest corresponding dynamical changes in the inner disk structure and variable shadowing of outer disk material. We propose several possible sources for the structural changes, including a variable accretion rate or a stellar or planetary companion embedded in the disk. Our results indicate that variability studies in the infrared can provide important new constraints on protoplanetary disk behavior.Comment: 15 pages, 4 figures, accepted to ApJ Letter

Highly Variable Extinction and Accretion in the Jet-driving Class I Type Young Star PTF 10nvg (V2492 Cyg, IRAS 20496+4354)

We report extensive new photometry and spectroscopy of the highly variable young stellar object PTF 10nvg including optical and near-infrared time series data as well as mid-infrared and millimeter data. Following the previously reported 2010 rise, during 2011 and 2012 the source underwent additional episodes of brightening and dimming events including prolonged faint states. The observed high-amplitude variations are largely consistent with extinction changes having a 220 day quasi-periodic signal. Spectral evolution includes not only changes in the spectral slope but correlated variation in the prominence of TiO/VO/CO bands and atomic line emission, as well as anticorrelated variation in forbidden line emission which, along with H_2, dominates optical and infrared spectra at faint epochs. Neutral and singly-ionized atomic species are likely formed in an accretion flow and/or impact while the origin of zero-velocity atomic LiI 6707 in emission is unknown. Forbidden lines, including several rare species, exhibit blueshifted emission profiles and likely arise from an outflow/jet. Several of these lines are also seen spatially offset from the continuum source position, presumably in a shocked region of an extended jet. CARMA maps resolve on larger scales a spatially extended outflow in mm-wavelength CO. We attribute the observed photometric and spectroscopic behavior in terms of occultation of the central star as well as the bright inner disk and the accretion/outflow zones that renders shocked gas in the inner part of the jet amenable to observation at the faint epochs. We discuss PTF 10nvg as a source exhibiting both accretion-driven (perhaps analogous to V1647 Ori) and extinction-driven (perhaps analogous to UX Ori or GM Cep) high-amplitude variability phenomena.Comment: accepted to AJ - in press (74 pages

Predicting electrical conductivity in Cu/Nb composites: a combined model-experiment study

The generation of high magnetic fields requires materials with high electric conductivity and good strength properties. Cu/Nb composites are considered to be good candidates for this purpose. In this work we aim to predict, from theory, the dependence of electric conductivity on the microstructure, most notably on the layer thickness and grain sizes. We also conducted experiments to calibrate and validate our simulations. Bimetal interfaces and grain boundaries are confirmed to have the largest impact on conductivity in this composite material. In this approach, a distribution of the layer thickness is accounted for in order to better model the experimentally observed microstructure. Because layer thicknesses below the mean free path of Cu significantly degrade the conductivity, an average layer thickness larger than expected may be needed to meet conductivity requirements in order to minimize these smaller layers in the distribution. We also investigate the effect of variations in volume fraction of Nb and temperature on the material's conductivity.Comment: 19 pages, 5 figures, 2 table

Hypothalamic orexin’s role in exacerbated cutaneous vasodilation responses to an anxiogenic stimulus in a surgical menopause model

Distressing symptoms such as hot flashes and sleep disturbances affect over 70% of women approaching menopause for an average of 4-7 years, and recent large cohort studies have shown that anxiety and stress are strongly associated with more severe and persistent hot flashes and can induce hot flashes. Although high estrogen doses alleviate symptoms, extended use increases health risks, and current non-hormonal therapies are marginally better than placebo. The lack of effective non-hormonal treatments is largely due to the limited understanding of the mechanisms that underlie menopausal symptoms. One mechanistic pathway that has not been explored is the wake-promoting orexin neuropeptide system. Orexin is exclusively synthesized in the estrogen receptor rich perifornical hypothalamic region, and has an emerging role in anxiety and thermoregulation. In female rodents, estrogens tonically inhibit expression of orexin, and estrogen replacement normalizes severely elevated central orexin levels in postmenopausal women. Using an ovariectomy menopause model, we demonstrated that an anxiogenic compound elicited exacerbated hot flash-associated increases in tail skin temperature (TST, that is blocked with estrogen), and cellular responses in orexin neurons and efferent targets. Furthermore, systemic administration of centrally active, selective orexin 1 or 2 and dual receptor antagonists attenuated or blocked TST responses, respectively. This included the reformulated Suvorexant, which was recently FDA-approved for treating insomnia. Collectively, our data support the hypothesis that dramatic loss of estrogen tone during menopausal states leads to a hyperactive orexin system that contributes to symptoms such as anxiety, insomnia, and more severe hot flashes. Additionally, orexin receptor antagonists may represent a novel non-hormonal therapy for treating menopausal symptoms, with minimal side effects

A newly-described host-symbiont interaction: first record of Dinocheirus panzeri (Pseudoscorpiones: Chernetidae) associated with Cyanistes caeruleus (Paridae) nests

We report the discovery of a female Dinocheirus panzeri (Chernetidae) (C.L. Koch 1837) in a Cyanistes caeruleus (Linnaeus 1758) nest built in a wooden nestbox at Nagshead Nature Reserve, Gloucestershire, UK. The nest was collected within 24 hours post-fledging under English Nature licence 20060590 as part of a larger project and double sealed to prevent cross-contamination

Empirically testing the effectiveness of thermal imaging as a tool for identification of large mammals in the African bushveldt

Monitoring animal populations often relies on direct visual observations. This is problematic at night when spotlighting can cause misidentification and inaccurate counting. Using infrared thermography (IRT) could potentially solve these difficulties, but reliability is uncertain. Here, we test the accuracy of 24 observers, differing in experience and skill levels, in identifying antelope species from IRT photographs taken in the African bush. Overall, 38% of identifications were correct to species level and 50% were correct to genus/subfamily level. Identification accuracy depended on the confidence and skill of the observer (positive relationship), the number of animals present (positive relationship), and the distance at which it was taken (negative relationship). Species with characteristic features, horn morphology, or posture were identified with ~80% accuracy (e.g. wildebeest, kudu, impala) while others were considerably lower (e.g. blesbok, waterbuck). Experience significantly improved identification accuracy but the effect was not consistent between species and even experienced observers struggled to identify red hartebeest, reedbuck and eland. Counting inaccuracies were commonplace, particularly when group size was large. We conclude that thermal characteristics of species and experience of observers can pose challenges for African field ecologists but IRT can be used to identify and count some species accurately, especially <100m

Breast MRI Utilization in Older Patients with Newly Diagnosed Breast Cancer

Recently, use of advanced imaging modalities, such as MRI, has increased dramatically. One novel but still evolving use for MRI is in the diagnosis and clinical staging of newly diagnosed breast cancer patients. Compared with mammography, MRI is more sensitive, but less specific, and far more expensive. The purpose of this study is to examine the prevalence and predictors of MRI use for clinical staging in older women with newly diagnosed breast cancer