84 research outputs found
Co-habitation and Migration: Urban Design for Bird Migratory Pathways
Urban landscapes are intricate systems interacting throughout the globe. Over the past decades, urban development has widely sprawled and fragmented flyway systems and corridors. This has led to many changes in species composition and has even caused the extinction of some animals (Marzluff 1997). Recent studies have indicated that there exists a protective or restorative design to create stepping-stone connectivity in urban areas. This study looks to understanding potential benefits in urban biodiversity, animal species protection, and urban benefits of green roof designs
Soil Bulk Density Variability in a Restored Prairie Ecosystem
Soils act as the foundation for all terrestrial biotic activity. Given this it is important to consider the factors that influence the physical makeup of soil as well as the management practices that can lead to changes and significant biological implications. Beginning in 1999 Cedarville University established a Prairie Restoration Site. In the past fifteen years work has been to done to reseed the area with native prairie grasses as well as to introduce regular disturbances that are common to prairie grasslands, such as fire. The goal of this work the goal has been to aid a system in ecological succession. In the current study, we seek to evaluate the success of this with regard to the corresponding changes in the soil environment. We look to distinguish this source of variability from the natural variability introduced by the physical landscape (slope) and the resulting soil series. To evaluate these ideas we will investigate how two factors, soil series (corresponding to slope position) and prairie restoration, affect soil bulk density.
We collected soil samples (to a depth of 15 cm) from the restored prairie as well as the adjacent area. In addition to this variable, we acquired samples in both locations across a range of three different soil series distributed within this same area. Specifically, we collected samples from the “XeB-Xenia B,” “Ra-Ragsdale,” and “Russel-Miamian - RvB2” soil types. We will use a two factor ANOVA to evaluate the impact of a change in soil series, or prairie restoration on soil bulk density
A Class of Eccentric Binaries with Dynamic Tidal Distortions Discovered with Kepler
We have discovered a class of eccentric binary systems within the Kepler data
archive that have dynamic tidal distortions and tidally-induced pulsations.
Each has a uniquely shaped light curve that is characterized by periodic
brightening or variability at time scales of 4-20 days, frequently accompanied
by shorter period oscillations. We can explain the dominant features of the
entire class with orbitally-varying tidal forces that occur in close, eccentric
binary systems. The large variety of light curve shapes arises from viewing
systems at different angles. This hypothesis is supported by spectroscopic
radial velocity measurements for five systems, each showing evidence of being
in an eccentric binary system. Prior to the discovery of these 17 new systems,
only four stars, where KOI-54 is the best example, were known to have evidence
of these dynamic tides and tidally-induced oscillations. We perform preliminary
fits to the light curves and radial velocity data, present the overall
properties of this class and discuss the work required to accurately model
these systems.Comment: 13 pages, submitted to Ap
KOI-54: The Kepler Discovery of Tidally Excited Pulsations and Brightenings in a Highly Eccentric Binary
Kepler observations of the star HD 187091 (KIC 8112039, hereafter KOI-54) revealed a remarkable light curve exhibiting sharp periodic brightening events every 41.8 days with a superimposed set of oscillations forming a beating pattern in phase with the brightenings. Spectroscopic observations revealed that this is a binary star with a highly eccentric orbit, e = 0.83. We are able to match the Kepler light curve and radial velocities with a nearly face-on (i = 5 degrees.5) binary star model in which the brightening events are caused by tidal distortion and irradiation of nearly identical A stars during their close periastron passage. The two dominant oscillations in the light curve, responsible for the beating pattern, have frequencies that are the 91st and 90th harmonic of the orbital frequency. The power spectrum of the light curve, after removing the binary star brightening component, reveals a large number of pulsations, 30 of which have a signal-to-noise ratio greater than or similar to 7. Nearly all of these pulsations have frequencies that are either integer multiples of the orbital frequency or are tidally split multiples of the orbital frequency. This pattern of frequencies unambiguously establishes the pulsations as resonances between the dynamic tides at periastron and the free oscillation modes of one or both of the stars. KOI-54 is only the fourth star to show such a phenomenon and is by far the richest in terms of excited modes.NASA, Science Mission DirectorateNASA NNX08AR14GEuropean Research Council under the European Community 227224W.M. Keck FoundationMcDonald Observator
Factors associated with mortality after proximal femoral fracture
Proximal femoral fractures are a serious complication, especially for elderly patients. Therefore, we have aimed to answer the following research question: What is the postfracture mortality rate in the elderly population and what are associated risk factors? For this, proximal femoral fractures that occurred between 1 January 2009 and 31 December 2019 were identified from the Medicare Physician Service Records database. The Kaplan–Meier (KM) method with the Fine and Gray subdistribution adaptation was used to determine rates of mortality. A semiparametric Cox regression model was applied, incorporating 23 measures as covariates to identify risk factors. The estimated 1 year mortality rate was 26.8% after head/neck fracture, 28.2% after intertrochanteric fracture, and 24.2% after subtrochanteric fracture. Male sex, age over 70 years, chronic obstructive pulmonary disease (COPD), cerebrovascular disease, chronic kidney disease, a concomitant fracture, congestive heart failure, diabetes mellitus, hypertension, insulin use, ischemic heart disease, morbid obesity, osteoporosis, tobacco dependence, and median household income were determined as risk factors for increased mortality. An early assessment of individual risk factors accessible for therapeutic treatment is crucial in the management of proximal femur fractures to aid in attempts at reducing the high mortality apparent in the elderly US population
Exile Vol. XXXVII No. 1
And It Was Sunday by Julie Gruen 1-6
Like a Lady by Grace Mulvihill 7
The Final You by Eric Franzon 8
Joseph\u27s Children by Seneca Murley 9
Ain\u27t the 1950s Anymore by Ellen Stader 10-12
Bonding Women by Shannon salser 13
Ice Man (for mami 1905-1975) by Anne Mulligan 14
The Car Salesman by Tom Ream 15
Cancelling the Bunny by Stewart Engesser 16-17
Richard Brautigan\u27s Body by Michael Payne 18-19
Dinner in Barcelona by Holly Kurtz 20
Untitled by Margaret Strachen 21
Candles by Eric Franzon 22
Summer Rules by Jim Cox 23-31
My Boat by Holly Kurtz 32
Untitled by Michael Payne 33
Half the Birds in the City by Tiffany Richardson 34-35
Down Queen Anne Hill by Julie Gruen 36-37
Your Music by Tim Emrick 38
Zephyrs by Steve Corinth 39-41
Mother by Anne Mulligan 42
As I Look to the Sky, Maize by Shannon Salser 43-45
Close Book before Striking by Sarah Verdon 46-47
Smoked by Tom Ream 48
Driving through Rain by Stewart Engesser 49-50
Contributors 51
Editorial decision is shared equally among the Editorial Board. -i
35th Yea
CLASH: Precise New Constraints on the Mass Profile of Abell 2261
We precisely constrain the inner mass profile of Abell 2261 (z=0.225) for the
first time and determine this cluster is not "over-concentrated" as found
previously, implying a formation time in agreement with {\Lambda}CDM
expectations. These results are based on strong lensing analyses of new 16-band
HST imaging obtained as part of the Cluster Lensing and Supernova survey with
Hubble (CLASH). Combining this with revised weak lensing analyses of Subaru
wide field imaging with 5-band Subaru + KPNO photometry, we place tight new
constraints on the halo virial mass M_vir = 2.2\pm0.2\times10^15 M\odot/h70
(within r \approx 3 Mpc/h70) and concentration c = 6.2 \pm 0.3 when assuming a
spherical halo. This agrees broadly with average c(M,z) predictions from recent
{\Lambda}CDM simulations which span 5 <~ 8. Our most significant
systematic uncertainty is halo elongation along the line of sight. To estimate
this, we also derive a mass profile based on archival Chandra X-ray
observations and find it to be ~35% lower than our lensing-derived profile at
r2500 ~ 600 kpc. Agreement can be achieved by a halo elongated with a ~2:1 axis
ratio along our line of sight. For this elongated halo model, we find M_vir =
1.7\pm0.2\times10^15 M\odot/h70 and c_vir = 4.6\pm0.2, placing rough lower
limits on these values. The need for halo elongation can be partially obviated
by non-thermal pressure support and, perhaps entirely, by systematic errors in
the X-ray mass measurements. We estimate the effect of background structures
based on MMT/Hectospec spectroscopic redshifts and find these tend to lower
Mvir further by ~7% and increase cvir by ~5%.Comment: Submitted to the Astrophysical Journal. 19 pages, 14 figure
Fast Mapping of Short Sequences with Mismatches, Insertions and Deletions Using Index Structures
With few exceptions, current methods for short read mapping make use of simple seed heuristics to speed up the search. Most of the underlying matching models neglect the necessity to allow not only mismatches, but also insertions and deletions. Current evaluations indicate, however, that very different error models apply to the novel high-throughput sequencing methods. While the most frequent error-type in Illumina reads are mismatches, reads produced by 454's GS FLX predominantly contain insertions and deletions (indels). Even though 454 sequencers are able to produce longer reads, the method is frequently applied to small RNA (miRNA and siRNA) sequencing. Fast and accurate matching in particular of short reads with diverse errors is therefore a pressing practical problem. We introduce a matching model for short reads that can, besides mismatches, also cope with indels. It addresses different error models. For example, it can handle the problem of leading and trailing contaminations caused by primers and poly-A tails in transcriptomics or the length-dependent increase of error rates. In these contexts, it thus simplifies the tedious and error-prone trimming step. For efficient searches, our method utilizes index structures in the form of enhanced suffix arrays. In a comparison with current methods for short read mapping, the presented approach shows significantly increased performance not only for 454 reads, but also for Illumina reads. Our approach is implemented in the software segemehl available at http://www.bioinf.uni-leipzig.de/Software/segemehl/
The Complete Genome Sequence of Thermoproteus tenax: A Physiologically Versatile Member of the Crenarchaeota
Here, we report on the complete genome sequence of the hyperthermophilic Crenarchaeum Thermoproteus tenax (strain Kra 1, DSM 2078(T)) a type strain of the crenarchaeotal order Thermoproteales. Its circular 1.84-megabase genome harbors no extrachromosomal elements and 2,051 open reading frames are identified, covering 90.6% of the complete sequence, which represents a high coding density. Derived from the gene content, T. tenax is a representative member of the Crenarchaeota. The organism is strictly anaerobic and sulfur-dependent with optimal growth at 86 degrees C and pH 5.6. One particular feature is the great metabolic versatility, which is not accompanied by a distinct increase of genome size or information density as compared to other Crenarchaeota. T. tenax is able to grow chemolithoautotrophically (CO2/H-2) as well as chemoorganoheterotrophically in presence of various organic substrates. All pathways for synthesizing the 20 proteinogenic amino acids are present. In addition, two presumably complete gene sets for NADH:quinone oxidoreductase (complex I) were identified in the genome and there is evidence that either NADH or reduced ferredoxin might serve as electron donor. Beside the typical archaeal A(0)A(1)-ATP synthase, a membrane-bound pyrophosphatase is found, which might contribute to energy conservation. Surprisingly, all genes required for dissimilatory sulfate reduction are present, which is confirmed by growth experiments. Mentionable is furthermore, the presence of two proteins (ParA family ATPase, actin-like protein) that might be involved in cell division in Thermoproteales, where the ESCRT system is absent, and of genes involved in genetic competence (DprA, ComF) that is so far unique within Archaea
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Linking soil microbial community structure to potential carbon mineralization: A continental scale assessment of reduced tillage
Potential carbon mineralization (Cmin) is a commonly used indicator of soil health, with greater Cmin values interpreted as healthier soil. While Cmin values are typically greater in agricultural soils managed with minimal physical disturbance, the mechanisms driving the increases remain poorly understood. This study assessed bacterial and archaeal community structure and potential microbial drivers of Cmin in soils maintained under various degrees of physical disturbance. Potential carbon mineralization, 16S rRNA sequences, and soil characterization data were collected as part of the North American Project to Evaluate Soil Health Measurements (NAPESHM). Results showed that type of cropping system, intensity of physical disturbance, and soil pH influenced microbial sensitivity to physical disturbance. Furthermore, 28% of amplicon sequence variants (ASVs), which were important in modeling Cmin, were enriched under soils managed with minimal physical disturbance. Sequences identified as enriched under minimal disturbance and important for modeling Cmin, were linked to organisms which could produce extracellular polymeric substances and contained metabolic strategies suited for tolerating environmental stressors. Understanding how physical disturbance shapes microbial communities across climates and inherent soil properties and drives changes in Cmin provides the context necessary to evaluate management impacts on standardized measures of soil microbial activity
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