Hard x-ray polarimetry with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI)

Although designed primarily as a hard X-ray imager and spectrometer, the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is also capable of measuring the polarization of hard X-rays (20-100 keV) from solar flares. This capability arises from the inclusion of a small unobstructed Be scattering element that is strategically located within the cryostat that houses the array of nine germanium detectors. The Ge detectors are segmented, with both a front and rear active volume. Low energy photons (below about 100 keV) can reach a rear segment of a Ge detector only indirectly, by scattering. Low energy photons from the Sun have a direct path to the Be and have a high probability of Compton scattering into a rear segment of a Ge detector. The azimuthal distribution of these scattered photons carries with it a signature of the linear polarization of the incident flux. Sensitivity estimates, based on simulations and in-flight background measurements, indicate that a 20-100 keV polarization sensitivity of less than a few percent can be achieved for X-class flares

Reversible skew laurent polynomial rings and deformations of poisson automorphisms

A skew Laurent polynomial ring S = R[x(+/- 1); alpha] is reversible if it has a reversing automorphism, that is, an automorphism theta of period 2 that transposes x and x(-1) and restricts to an automorphism gamma of R with gamma = gamma(-1). We study invariants for reversing automorphisms and apply our methods to determine the rings of invariants of reversing automorphisms of the two most familiar examples of simple skew Laurent polynomial rings, namely a localization of the enveloping algebra of the two-dimensional non-abelian solvable Lie algebra and the coordinate ring of the quantum torus, both of which are deformations of Poisson algebras over the base field F. Their reversing automorphisms are deformations of Poisson automorphisms of those Poisson algebras. In each case, the ring of invariants of the Poisson automorphism is the coordinate ring B of a surface in F-3 and the ring of invariants S-theta of the reversing automorphism is a deformation of B and is a factor of a deformation of F[x(1), x(2), x(3)] for a Poisson bracket determined by the appropriate surface

Amish Economic Transformations: New Forms of Income and Wealth Distribution in a Traditionally “Flat” Community

The basic contours of the Amish economic transformation over the past few decades have been well documented, including the demographic squeeze that pushed many Amish out of farming, their embrace of cottage industries and, to a lesser extent, factory labor, and the social and cultural dilemmas created by successful entrepreneurship. Yet the effects of increasing market entanglement on the distribution of income and assets in Amish communities are still poorly understood. In this exploratory study, we draw on publicly available data from the U.S. Census, the Ohio Amish Directory, and records from real estate transactions to map out the distribution of income and land wealth in one predominantly Amish-populated Census Tract in Holmes County, OH. Our findings illustrate economic differentiation within the Amish community, as well as the ways in which affiliation and church leadership are associated with land holdings. Our case study raises important questions about growing economic inequalities that merit further exploration

Amish Economic Transformations: New Forms of Income and Wealth Distribution in a Traditionally “Flat” Community

The basic contours of the Amish economic transformation over the past few decades have been well documented, including the demographic squeeze that pushed many Amish out of farming, their embrace of cottage industries and, to a lesser extent, factory labor, and the social and cultural dilemmas created by successful entrepreneurship. Yet the effects of increasing market entanglement on the distribution of income and assets in Amish communities are still poorly understood. In this exploratory study, we draw on publicly available data from the U.S. Census, the Ohio Amish Directory, and records from real estate transactions to map out the distribution of income and land wealth in one predominantly Amish-populated Census Tract in Holmes County, OH. Our findings illustrate economic differentiation within the Amish community, as well as the ways in which affiliation and church leadership are associated with land holdings. Our case study raises important questions about growing economic inequalities that merit further exploration

Rapid ice discharge from southeast Greenland glaciers

This is the published version, also available here: http://dx.doi.org/10.1029/2004GL019474.[1] Interferometric synthetic-aperture radar (InSAR) observations of southeast Greenland glaciers acquired by the Earth Remote Sensing Satellites (ERS-1/2) in 1996 were combined with ice sounding radar data collected in the late 1990s to estimate a total discharge of 46 ± 3 km3 ice per year between 62°N and 66°N, which is significantly lower than a mass input of 29 ± 3 km3 ice per year calculated from a recent compilation of snow accumulation data. Further north, Helheim Glacier discharges 23 ± 1 km3/yr vs 30 ± 3 km3/yr accumulation; Kangerdlugssuaq Glacier discharges 29 ± 2 km3/yr vs 23 ± 2 km3/yr; and Daugaard-Jensen Glacier discharges 10.5 ± 0.6 km3/yr vs 10.5 ± 1 km3/yr. The mass balance of east Greenland glaciers is therefore dominated by the negative mass balance of southeast Greenland glaciers (−17 ± 4 km3/yr), equivalent to a sea level rise of 0.04 ± 0.01 mm/yr. Warmer and drier conditions cannot explain the imbalance which we attribute to long-term changes in ice dynamics

Improving undergraduate STEM education: The efficacy of discipline-based professional development

We sought to determine whether instructional practices used by undergraduate faculty in the geosciences have shifted from traditional teacher-centered lecture toward student-engaged teaching practices and to evaluate whether the national professional development program On the Cutting Edge (hereinafter Cutting Edge) has been a contributing factor in this change. We surveyed geoscience faculty across the United States in 2004, 2009, and 2012 and asked about teaching practices as well as levels of engagement in education research, scientific research, and professional development related to teaching. We tested these self-reported survey results with direct observations of teaching using the Reformed Teaching Observation Protocol, and we conducted interviews to understand what aspects of Cutting Edge have supported change. Survey data show that teaching strategies involving active learning have become more common, that these practices are concentrated in faculty who invest in learning about teaching, and that faculty investment in learning about teaching has increased. Regression analysis shows that, after controlling for other key influences, faculty who have participated in Cutting Edge programs and who regularly use resources on the Cutting Edge website are statistically more likely to use active learning teaching strategies. Cutting Edge participants also report that learning about teaching, the availability of teaching resources, and interactions with peers have supported changes in their teaching practice. Our data suggest that even one-time participation in a workshop with peers can lead to improved teaching by supporting a combination of affective and cognitive learning outcomes

Defect generation and deconfinement on corrugated topographies

We investigate topography-driven generation of defects in liquid crystals films coating frozen surfaces of spatially varying Gaussian curvature whose topology does not automatically require defects in the ground state. We study in particular disclination-unbinding transitions with increasing aspect ratio for a surface shaped as a Gaussian bump with an hexatic phase draped over it. The instability of a smooth ground state texture to the generation of a single defect is also discussed. Free boundary conditions for a single bump are considered as well as periodic arrays of bumps. Finally, we argue that defects on a bump encircled by an aligning wall undergo sharp deconfinement transitions as the aspect ratio of the surface is lowered.Comment: 24 page

Music therapy for end-of-life care: An updated systematic review.

BACKGROUND: Music therapy during palliative and end-of-life care is well established and positive benefits for patients have been reported. AIM: Assess the effectiveness of music therapy versus standard care alone or standard care in combination with other therapies for improving psychological, physiological and social outcomes among adult patients in any palliative care setting. DATA SOURCES: In order to update an existing Cochrane systematic review, we searched MEDLINE, CINAHL, EMBASE, PsycINFO, CENTRAL, ClinicalTrials.gov register and Current Controlled Trials register to identify randomised or quasi-randomised controlled trials published between 2009 and April 2015. Nine electronic music therapy journals were searched from 2009 until April 2015, along with reference lists and contact was made with key experts in music therapy. Only studies published in English were eligible for inclusion. Two reviewers independently screened titles, abstracts, assessed relevant studies for eligibility, extracted data and judged risk of bias for included studies. Disagreements were resolved through discussion with a third reviewer. Data were synthesised in Revman using the random effects model. Heterogeneity was assessed using I(2). RESULTS: Three studies were included in the review. Findings suggest that music therapy may be effective for helping to reduce pain in palliative care patients (standard mean deviation = -0.42, 95% confidence interval = -0.68 to -0.17, p = 0.001). CONCLUSION: Available evidence did not support the use of music therapy to improve overall quality of life in palliative care. While this review suggests that music therapy may be effective for reducing pain, this is based on studies with a high risk of bias. Further high-quality research is required

Estradiol and its metabolites and their association with knee osteoarthritis

Objective To determine if levels of endogenous estrogen or estrogen metabolites are associated with an increased risk of developing knee osteoarthritis (OA) in women. Methods Serum estradiol (E 2 ) and 2 urinary estrogen metabolites (2-hydroxyestrone and 16Α-hydroxyestrone) with radiographically defined prevalent and incident knee OA in 842 white and African American women from the Southeast Michigan Arthritis Cohort. Results The mean age and body mass index (BMI) of women in the cohort were 42.3 years and 28.5 kg/m 2 , respectively. Women who developed radiographically defined knee OA had significantly greater odds of having baseline endogenous early follicular phase estradiol concentrations in the lowest tertile (0.86; OR 1.86, 95% CI 1.01–3.44 compared with women with ratios in the 0.54–0.86 range), after adjustment for other covariates. Conclusion There were significant associations of lower baseline serum estradiol and urinary 2-hydroxyestrone with developing knee OA in middle-aged women.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55806/1/22005_ftp.pd

A generalizable data-driven multicellular model of pancreatic ductal adenocarcinoma.

BACKGROUND: Mechanistic models, when combined with pertinent data, can improve our knowledge regarding important molecular and cellular mechanisms found in cancer. These models make the prediction of tissue-level response to drug treatment possible, which can lead to new therapies and improved patient outcomes. Here we present a data-driven multiscale modeling framework to study molecular interactions between cancer, stromal, and immune cells found in the tumor microenvironment. We also develop methods to use molecular data available in The Cancer Genome Atlas to generate sample-specific models of cancer. RESULTS: By combining published models of different cells relevant to pancreatic ductal adenocarcinoma (PDAC), we built an agent-based model of the multicellular pancreatic tumor microenvironment, formally describing cell type-specific molecular interactions and cytokine-mediated cell-cell communications. We used an ensemble-based modeling approach to systematically explore how variations in the tumor microenvironment affect the viability of cancer cells. The results suggest that the autocrine loop involving EGF signaling is a key interaction modulator between pancreatic cancer and stellate cells. EGF is also found to be associated with previously described subtypes of PDAC. Moreover, the model allows a systematic exploration of the effect of possible therapeutic perturbations; our simulations suggest that reducing bFGF secretion by stellate cells will have, on average, a positive impact on cancer apoptosis. CONCLUSIONS: The developed framework allows model-driven hypotheses to be generated regarding therapeutically relevant PDAC states with potential molecular and cellular drivers indicating specific intervention strategies