Research Brief: Job-Mobility for People with Disabilities: Impact of Employer-Paid Health Insurance

As most employers appear to make decisions to offer EHI from an economic perspective, research has yet to demonstrate how such decisions could potentially contribute to higher turnover rates as indicated by job-mobility of workers, especially among employees with disabilities. This research brief describes the results from the analysis of large national survey data examining the relationship between employer-paid health insurance and the likelihood of job-change for people with and without disabilities

Verifying the mass-metallicity relation in damped Lyman-alpha selected galaxies at 0.1<z<3.2

A scaling relation has recently been suggested to combine the galaxy mass-metallicity (MZ) relation with metallicities of damped Lyman-alpha systems (DLAs) in quasar spectra. Based on this relation the stellar masses of the absorbing galaxies can be predicted. We test this prediction by measuring the stellar masses of 12 galaxies in confirmed DLA absorber - galaxy pairs in the redshift range 0.1<z<3.2. We find an excellent agreement between the predicted and measured stellar masses over three orders of magnitude, and we determine the average offset $\langle C_{[M/H]} \rangle$ = 0.44+/-0.10 between absorption and emission metallicities. We further test if $C_{[M/H]}$ could depend on the impact parameter and find a correlation at the 5.5sigma level. The impact parameter dependence of the metallicity corresponds to an average metallicity difference of -0.022+/-0.004 dex/kpc. By including this metallicity vs. impact parameter correlation in the prescription instead of $C_{[M/H]}$, the scatter reduces to 0.39 dex in log M*. We provide a prescription how to calculate the stellar mass (M*,DLA) of the galaxy when both the DLA metallicity and DLA galaxy impact parameter is known. We demonstrate that DLA galaxies follow the MZ relation for luminosity-selected galaxies at z=0.7 and z=2.2 when we include a correction for the correlation between impact parameter and metallicity.Comment: 15 pages, 6 figures. Major revision. Accepted for publication in MNRA

Search Bias Quantification: Investigating Political Bias in Social Media and Web Search

Users frequently use search systems on the Web as well as online social media to learn about ongoing events and public opinion on personalities. Prior studies have shown that the top-ranked results returned by these search engines can shape user opinion about the topic (e.g., event or person) being searched. In case of polarizing topics like politics, where multiple competing perspectives exist, the political bias in the top search results can play a significant role in shaping public opinion towards (or away from) certain perspectives. Given the considerable impact that search bias can have on the user, we propose a generalizable search bias quantification framework that not only measures the political bias in ranked list output by the search system but also decouples the bias introduced by the different sources—input data and ranking system. We apply our framework to study the political bias in searches related to 2016 US Presidential primaries in Twitter social media search and find that both input data and ranking system matter in determining the final search output bias seen by the users. And finally, we use the framework to compare the relative bias for two popular search systems—Twitter social media search and Google web search—for queries related to politicians and political events. We end by discussing some potential solutions to signal the bias in the search results to make the users more aware of them.publishe

Motion of a Vector Particle in a Curved Spacetime. I. Lagrangian Approach

From the simple Lagrangian the equations of motion for the particle with spin are derived. The spin is shown to be conserved on the particle world-line. In the absence of a spin the equation coincides with that of a geodesic. The equations of motion are valid for massless particles as well, since mass does not enter the equations explicitely.Comment: 6 pages, uses mpla1.sty, published in MPLA, replaced with corrected typo

Assessment of Vegetative Phenology with Respect to Leaf Elongation Pattern of Avicennia Marina and Rhizophora Mucronata in Hajambro Creek, Indus Delta, Pakistan

Leaves emergence and the rate of elongation have been studied in Hajambro creek in Indus deltaic region, Pakistan. Leaves emergence was found higher during the summer months (mostly pre-monsoon period), that was March April, May and June. Leaves of A. marina that were observed from March to July, till the leaves reached their maximum length (about 77 mm), showed a gradual increase in their length, reaching maximum in April. Leaves of Avicennia marina reached their maximum length (about 77 mm) in about 113 days. The leaves showed gradual increase in their length, reaching maximum in April (0.97mm d-1). The per-day increment in length was 0.54 mm d-1. As reaching their maximum length (77mm), the per-day increment in the length gradually slower down. The leaves of Rhizophora mucronata were observed from February to November. The leaves of Rhizophora mucronata showed elongation rate of 0.24 mm d-1 from the day of the first observation till the leaves reached their maximum length (120 mm). The maximum time required by the leaves to reach their maximum length (120 mm) was 236 days. The rates of elongation of leaves are also fast in summer. The rate of elongation of the leaves was found to be highly correlated with the temperature (

The maintenance of elevated active chlorine levels in the Antarctic lower stratosphere through HCl null cycles

The Antarctic ozone hole arises from ozone destruction driven by elevated levels of ozone destroying ("active") chlorine in Antarctic spring. These elevated levels of active chlorine have to be formed first and then maintained throughout the period of ozone destruction. It is a matter of debate how this maintenance of active chlorine is brought about in Antarctic spring, when the rate of formation of HCl (considered to be the main chlorine deactivation mechanism in Antarctica) is extremely high. Here we show that in the heart of the ozone hole (16–18 km or 85–55 hPa, in the core of the vortex), high levels of active chlorine are maintained by effective chemical cycles (referred to as HCl null cycles hereafter). In these cycles, the formation of HCl is balanced by immediate reactivation, i.e. by immediate reformation of active chlorine. Under these conditions, polar stratospheric clouds sequester HNO3 and thereby cause NO2 concentrations to be low. These HCl null cycles allow active chlorine levels to be maintained in the Antarctic lower stratosphere and thus rapid ozone destruction to occur. For the observed almost complete activation of stratospheric chlorine in the lower stratosphere, the heterogeneous reaction HCl + HOCl is essential; the production of HOCl occurs via HO2 + ClO, with the HO2 resulting from CH2O photolysis. These results are important for assessing the impact of changes of the future stratospheric composition on the recovery of the ozone hole. Our simulations indicate that, in the lower stratosphere, future increased methane concentrations will not lead to enhanced chlorine deactivation (through the reaction CH4 + Cl  ⟶  HCl + CH3) and that extreme ozone destruction to levels below  ≈ 0.1 ppm will occur until mid-century

The epidemiology, antibiotic resistance and post-discharge course of peritonsillar abscesses in London, Ontario

Background: Peritonsillar abscesses (PTA) are a common complication of tonsillitis. Recent global epidemiological data regarding PTAs have demonstrated increasing antimicrobial resistance patterns. No similar studies have been conducted in Canada and no Canadian study has examined the post-discharge course of treated patients. Methods: A prospective observational study of the epidemiology, antibiotic resistance and post-discharge course of patients presenting with a peritonsillar abscess to the Emergency Department in London, Ontario over one year. A follow-up telephone survey was conducted 2-3 weeks after abscess drainage. Results: 60 patients were diagnosed with an abscess, giving an incidence of 12/100,000. 46 patients were enrolled in the study; the average duration of symptoms prior to presentation was 6 days, with 51% treated with antibiotics prior to presentation. Streptococcus pyogenes and Streptococcus anginosus were present in 56% of isolates and of those, 7/23 (32%) of specimens demonstrated resistance to clindamycin. Eight patients were treated with clindamycin and had a culture that was resistant, yet only one had recurrence. Telephone follow-up was possible for 38 patients: 51% of patients reported a return to solid food within 2 days, and 75% reported no pain by 5 days. Resolution of trismus took a week or longer for 51%. Interpretation: Clindamycin resistance was identified in a third of Streptococcus isolates, which should be taken into account when prescribing antibiotics. Routine culture appears unnecessary as patients recover quickly from outpatient drainage and empiric therapy, with less pain than expected, but trismus takes time to resolve. © 2013 Sowerby et al.; licensee BioMed Central Ltd