The Column Density Distribution Function at z=0 from HI Selected Galaxies

We have measured the column density distribution function, f(N), at z=0 using 21-cm HI emission from galaxies selected from a blind HI survey. f(N) is found to be smaller and flatter at z=0 than indicated by high-redshift measurements of Damped Lyman-alpha (DLA) systems, consistent with the predictions of hierarchical galaxy formation. The derived DLA number density per unit redshift, dn/dz =0.058, is in moderate agreement with values calculated from low-redshift QSO absorption line studies. We use two different methods to determine the types of galaxies which contribute most to the DLA cross-section: comparing the power law slope of f(N) to theoretical predictions and analysing contributions to dn/dz. We find that comparison of the power law slope cannot rule out spiral discs as the dominant galaxy type responsible for DLA systems. Analysis of dn/dz however, is much more discriminating. We find that galaxies with log M_HI < 9.0 make up 34% of dn/dz; Irregular and Magellanic types contribute 25%; galaxies with surface brightness > 24 mag arcsec^{-2} account for 22% and sub-L* galaxies contribute 45% to dn/dz. We conclude that a large range of galaxy types give rise to DLA systems, not just large spiral galaxies as previously speculated.Comment: 13 pages, low resolution figures in the appendix, MNRAS accepte

Local Column Density Distribution Function from HI selected galaxies

The cross-section of sky occupied by a particular neutral hydrogen column density provides insight into the nature of Lyman-alpha absorption systems. We have measured this column density distribution at z=0 using 21-cm HI emission from a blind survey. A subsample of HI Parkes All Sky Survey (HIPASS) galaxies have been imaged with the Australia Telescope Compact Array (ATCA). The contribution of low HI mass galaxies 10^7.5 to 10^8 M_solar is compared to that of M_star (10^10 to 10^10.5 M_solar) galaxies. We find that the column density distribution function is dominated by low HI mass galaxies with column densities in the range 3x10^18 to 2x10^20 cm^-2. This result is not intuitively obvious. M_star galaxies may contain the bulk of the HI gas, but the cross-section presented by low HI mass galaxies 10^7.5 to 10^8 M_solar is greater at moderate column densities. This result implies that moderate column density Lyman-alpha absorption systems may be caused by a range of galaxy types and not just large spiral galaxies as originally thought.Comment: 5 pages, including 1 figure. To appear in "Extragalactic Gas at Low Redshift" (ASP Conf. Series, Weymann Conf.

Fabrication and Characterization of a Magnetohydrodynamic Micropump from Polydimethylsiloxane (PDMS)

Microfluidics is a growing area of study in recent years, particularly for lab-on-a-chip applications. Fluids must oftentimes be transported from one location on the chip to another. This study focuses on the fabrication and characterization of a magnetohydrodynamic micropump. The device was fabricated in the Rose-Hulman Institute of Technology MiNDS facility, and consisted of a PDMS channel and titanium electrodes supported on a glass slide with a permanent magnet. An Arduino microcontroller capable of pulse width modulation (PWM) was used to control the electrical potential. An electrode design that spanned the full length of the channel was successful in driving fluid motion. Erioglaucine disodium salt blue dye was used to track the fluid motion through the channel, and appeared to have a greater impact on the apparent fluid velocity than sodium chloride. Of the PWM duty cycles tested, 75% had the highest apparent fluid velocity. The titanium that contacted the fluid anodized, indicating it is best suited for disposable applications

Evolution of damped Lyman alpha kinematics and the effect of spatial resolution on 21-cm measurements

We have investigated the effect of spatial resolution on determining pencil-beam like velocity widths and column densities in galaxies. Three 21-cm datasets are used, the HIPASS galaxy catalogue, a subset of HIPASS galaxies with ATCA maps and a high-resolution image of the LMC. Velocity widths measured from 21-cm emission in local galaxies are compared with those measured in intermediate redshift Damped Lyman alpha (DLA) absorbers. We conclude that spatial resolution has a severe effect on measuring pencil-beam like velocity widths in galaxies. Spatial smoothing by a factor of 240 is shown to increase the median velocity width by a factor of two. Thus any difference between velocity widths measured from global profiles or low spatial resolution 21-cm maps at z=0 and DLAs at z>1 cannot unambiguously be attributed to galaxy evolution. The effect on column density measurements is less severe and the values of dN/dz from local low-resolution 21-cm measurements are expected to be overestimated by only ~10 per cent.Comment: 5 pages, 6 figures, accepted for publication in MNRAS letter

Diffusion MRI and Pharmacological Enhancement of Motor Recovery after Stroke

The primary goal of these studies is to enhance recovery of motor function following stroke and to understand the relationship between dMRI measures and the cellular, functional, and behavioral changes acutely and chronically following rehabilitation. We hypothesize that dMRI will be a sensitive tool to identify microstructural changes acutely and chronically following stroke and that promoting mitochondria biogenesis will lead to better functional recovery and induce structural and functional plasticity following rehabilitative training. Towards this goal, we used a combination of sensitive behavioral, immunohistochemical and mitochondrial-related molecular markers, and diffusion magnetic resonance imaging (dMRI) to investigate the time course of acute and chronic stroke effects. We were able to detect acute changes in dMRI metrics and correlate those changes with functional and morphological plasticity following stroke. Our work has shown that mean kurtosis, a dMRI metric, increased acutely after stroke and persists days poststroke in the lesion core. We found strong correlations between mean diffusivity and astrogliosis in the perilesional stroke area. There were no correlations between dendritic and axonal surface densities and dMRI metrics acutely following stroke. However, behavioral-induced and learning-induced neural plasticity was not detected with dMRI changes chronically in perilesional grey matter or white matter. Our studies have revealed mitochondria dysfunction that persists for at least six days post stroke in ipsilesional cortex and striatum following a focal sensorimotor (SMC) ischemic lesion. Therefore, we proposed that pharmacologically enhancing mitochondria function and biogenesis would promote recovery after stroke when administered early after stroke. We found that giving a drug known to induce mitochondria biogenesis, formoterol, a FDA approved long-lasting β2-adrenergic receptor agonist, twenty-four hours after SMC ischemic lesions caused a full restoration of markers of mitochondria function in the striatum three days post stroke and stimulates a partial recovery of functional markers in the cortex six days post-stroke. Our studies revealed that animals given formoterol (0.1mg/kg) combined with motor rehabilitative training (RT) daily for 15 days leads to better recovery of motor function than animals given vehicle treatment and RT. These data demonstrate that stimulating mitochondria biogenesis acutely after stroke enhances functional motor recovery

The Ideal Deal: How Local Governments Can Get More for Their Economic Development Dollar

This handbook is designed to provide local economic development practitioners with an important tool. It takes the reader step-by-step through the different elements of contracts that treat public incentive packages as a quid pro quo for public benefits. Each section discusses a different element of the ideal deal: valuation of public costs and benefits, performance standards, disclosure and oversight, and enforcement. In each section we provide detailed examples of model provisions used by local governments in their incentive legislation, ordinances, and contracts -- information that has not before been obtained or recorded in any systematic way. These examples are meant to both illustrate the key principles for negotiating ideal deals and also serve as templates for actual contract language. They are supplemented with commentary culled from interviews conducted with local government officials, academic studies, and reports by watchdog organizations around the country.https://repository.law.umich.edu/books/1004/thumbnail.jp

The Ideal Deal: How Local Governments Can Get More for Their Economic Development Dollar

This handbook is designed to provide local economic development practitioners with an important tool. It takes the reader step-by-step through the different elements of contracts that treat public incentive packages as a quid pro quo for public benefits. Each section discusses a different element of the ideal deal: valuation of public costs and benefits, performance standards, disclosure and oversight, and enforcement. In each section we provide detailed examples of model provisions used by local governments in their incentive legislation, ordinances, and contracts -- information that has not before been obtained or recorded in any systematic way. These examples are meant to both illustrate the key principles for negotiating ideal deals and also serve as templates for actual contract language. They are supplemented with commentary culled from interviews conducted with local government officials, academic studies, and reports by watchdog organizations around the country.https://repository.law.umich.edu/books/1004/thumbnail.jp

Leveraging Interactive Maps as a Resource Discovery Tool: Envisioning a Repository, Collection or Series with a Map-driven Interface

Those of us with Digital Commons sites may already have download based live-maps embedded on one or more landing pages of our collections. What if we created a map for end-users to search our series in new ways? In this sandbox, two members of the LSRD-SIS executive board come together to share a show-and-tell-style tour of 3 map-based interfaces for a variety of legal resources, from in-house developed examples to a larger database provider like HeinOnline. Through these examples, we hope attendees will engage in brainstorming ways we could creatively integrate maps to leverage them as a more user-centered discovery tool for our organization’s own legal repository collections. We want these examples help repository administrators and librarians to collectively contemplate how transferrable and logistically plausible it would be to design similar UX experiences that work with our repositories; pivoting from a map displaying live-downloads of what others have found to a version of this style search tool that lets site visitors use the map to explore our collections in new ways. This short informal paper introduces the three primary examples for discussion: 1. Local Nebraska Laws Map - LibGuides backend, public user focused 2. Call All Papers Map - Drupal backend, faculty user focused 3. State Constitution\u27s Illustrated - HeinOnline resources we are all familiar wit