More Than Freedom: Fighting for Black Citizenship in a White Republic, 1829-1889

How Citizenship was Defined and Defended by African American Boston In More Than Freedom: Fighting for Black Citizenship in a White Republic, 1829-1889, Stephen Kantrowitz examines the political and social activism of free, ex-slave, and fugitive slave African Americans living and ...

Comparison of Classification Algorithms and Undersampling Methods on Employee Churn Prediction: A Case Study of a Tech Company

Churn prediction is a common data mining problem that many companies face across industries. More commonly, customer churn has been studied extensively within the telecommunications industry where there is low customer retention due to high market competition. Similar to customer churn, employee churn is very costly to a company and by not deploying proper risk mitigation strategies, profits cannot be maximized, and valuable employees may leave the company. The cost to replace an employee is exponentially higher than finding a replacement, so it is in any company’s best interest to prioritize employee retention. This research combines machine learning techniques with undersampling in hopes of identifying employees at risk of churn so retention strategies can be implemented before it is too late. Four different classification algorithms are tested on a variety of undersampled datasets in order to find the most effective undersampling and classification method for predicting employee churn. Statistical analysis is conducted on the appropriate evaluation metrics to find the most significant methods. The results of this study can be used by the company to target individuals at risk of churn so that risk mitigation strategies can be effective in retaining the valuable employees. Methods and results can be tested and applied across different industries and companies

Migration strategies of shorebirds during the non-breeding season with particular reference to the Sanderling (Calidris alba)

This study comprises two parts, one based at the Wash and one at Teesside, Dye-marking of samples of oystercatcher, grey plover, knot, sanderling, dunlin, bar-tailed godwit, curlew, redshank and turnstone was undertaken to determine differences in the degree of mobility within the Wash. Most information relates to spring tide roosts. Wash Wader Ringing Group recaptures within the Wash, within a single season, were examined for sanderlings and dunlin. There were few results for grey plover, bar-tailed godwit, curlew or redshank. Results for other species indicate a range of mobility - in order of increasing mobility these are dunlin and turnstone, sanderling, oystercatcher, knot. Under lying reasons for mobility were associated with flights to spring tide roosts, increases in diurnal time spent feeding and, possibly, exploratory flights in search of unpredictable food resources. At Teesside, individually colour-ringed sanderlings were studied for differences in timing of use of Teesside and differences in degree of mobility. Generally, individuals display consistency in returning to Teesside each year and arrival and departure dates are similar from year to year for each individual. A continuum of sanderling mobility is apparent. There appears to be a balance between net advantages and disadvantages accruing from variations in mobility as estimates of survival rates indicate'. Heightened mobility was apparent by some individuals during severe winters and was interpreted as movement in search of better foraging conditions

Eligibility of patients with Staphylococcus aureus bacteraemia for early oral switch

To identify people with low-risk Staphylococcus aureus bacteraemia (SAB), the SABATO investigators screened 5063 people, finding 213 (4·2%) meeting their eligibility criteria1. This low proportion of eligible patients led the authors to question if low-risk SAB is clinically relevant. We aimed to determine the clinical relevance of the SABATO definition of low-risk SAB, and if the trial population was representative of potentially eligible real-world patients. Data was collected retrospectively for 464 consecutive adults with SAB at our institution (Supplementary Figure), approved by the South East Scotland Research Ethics Committee (23/SS/0025). We then applied the SABATO inclusion and exclusion criteria to identify potentially eligible real-world patients.Of the 464 patients in our cohort, 71 (15·3%) would have been potentially eligible for inclusion in the trial. Acquisition of SAB in these patients was mainly nosocomial (35/71, 49·3%). Key cohort characteristics reported by the trial were very similar when comparing trial participants with potentially eligible real-world patients, although the median Charlson Comorbidity Index was lower in the trial cohort (Table). An intravenous catheter was the most common source of SAB in both cohorts, but there was a higher proportion of SAB from an unknown source in the real-world group (p=0·0015). An unknown source is a risk factor for complications2,3 and further evaluation combined with intensive follow-up of early oral switch should be considered in this group.Implanted prosthetic material is a component of the IDSA definition of complicated SAB4 but with certain caveats was not an absolute exclusion criterion in the SABATO trial. Nine potentially eligible real-world patients had prosthetic material in situ (n=4 cardiac devices and n=5 orthopaedic implants). This data was not reported for trial participants but could further increase confidence in applicability of the findings. No laboratory or physiology data from the time of the index blood culture was reported but might have been helpful to quantify disease severity and guide patient selection (Supplementary Table). We suggest this supports standardised collection and reporting of cohort characteristics in SAB trials to improve comparability between studies, which is often complicated by variability in the cohort characteristics reported5.We conclude that the sub-group of low-risk SAB studied in the SABATO trial is clinically relevant and find the similarities between randomised and real-world eligible patients re-assuring. Implementation of SABATO findings should be done cautiously and studied prospectively, especially when applied to patients with SAB of unknown source who were infrequently included in the trial.<br/

Direct acoustic profiling of DNA hybridisation using HSV type 1 viral sequences

We describe the detection of specific, conserved DNA sequences of herpes simplex virus (HSV) type 1 by means of a novel, high sensitivity acoustic biosensor. Repeated assays on planar and polymeric carboxylic acid- and biotin-presenting surface chemistries enabled statistical comparison of assay specificity and sensitivity and evaluation of assay Z-factor scores. Using a three minute hybridisation with NeutrAvidin capture for signal enhancement, it was possible to detect HSV viral nucleic acids at 5.2 6 10211 M concentration. c The Royal Society of Chemistry 200

Urinary Metabolites of Organophosphate Flame Retardants: Temporal Variability and Correlations with House Dust Concentrations

Background: A reduction in the use of polybrominated diphenyl ethers (PBDEs) because of human health concerns may result in an increased use of and human exposure to organophosphate flame retardants (OPFRs). Human exposure and health studies of OPFRs are lacking. Objectives: We sought to define the degree of temporal variability in urinary OPFR metabolites in order to inform epidemiologic study design, and to explore a potential primary source of exposure by examining the relationship between OPFRs in house dust and their metabolites in urine. Methods: Nine repeated urine samples were collected from 7 men over the course of 3 months and analyzed for bis(1,3-dichloro-2-propyl) phosphate (BDCPP) and diphenyl phosphate (DPP), metabolites of the OPFRs tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and triphenyl phosphate (TPP), respectively. Intraclass correlation coefficients (ICCs) were calculated to characterize temporal reliability. Paired house dust and urine samples were collected from 45 men. Results: BDCPP was detected in 91% of urine samples, and DPP in 96%. Urinary BDCPP showed moderate-to-strong temporal reliability (ICC range, 0.55–0.72). ICCs for DPP were lower, but moderately reliable (range, 0.35–0.51). There was a weak [Spearman r (rS) = 0.31] but significant (p = 0.03) correlation between urinary BDCPP and TDCPP concentrations in house dust that strengthened when nondetects (rS = 0.47) were excluded. There was no correlation between uncorrected DPP and TPP measured in house dust (rS < 0.1). Conclusions: Household dust may be an important source of exposure to TDCPP but not TPP. Urinary concentrations of BDCPP and DPP were moderately to highly reliable within individuals over 3 months

Seeing Speech: Ultrasound-based Multimedia Resources for Pronunciation Learning in Indigenous Languages

Pronunciation is an important aspect of Indigenous language learning, and one which requires creative community-oriented solutions. Towards this end, we have developed a pronunciation learning tool that incorporates ultrasound technology to give learners a visual aid to help them articulate unfamiliar and/or challenging sounds. Ultrasound is used to create videos of a model speaker’s tongue movements during speech, which are then overlaid on videos of an external profile view of the model’s head to create ultrasound-enhanced pronunciation videos for individual words or sounds. A key advantage of these videos is that learners are able see how speech is produced rather than just hear and try to mimic it. Although ultrasound-enhanced videos were originally developed for commonly taught languages such as Japanese and French, there has been widespread interest from Indigenous communities in Western Canada to develop their own customized videos. This paper reports on three collaborations between linguists and communities in British Columbia to develop ultrasound-enhanced videos for the SENĆOŦEN, Secwepemc, and Halq’emeylem languages. These videos can give learners a new way to learn pronunciation that focuses on seeing speech, and can create new documentation of understudied sound systems for future generations.National Foreign Language Resource Cente

A map of the day-night contrast of the extrasolar planet HD 189733b

"Hot Jupiter" extrasolar planets are expected to be tidally locked because they are close (<0.05 astronomical units, where 1 AU is the average Sun-Earth distance) to their parent stars, resulting in permanent daysides and nightsides. By observing systems where the planet and star periodically eclipse each other, several groups have been able to estimate the temperatures of the daysides of these planets. A key question is whether the atmosphere is able to transport the energy incident upon the dayside to the nightside, which will determine the temperature at different points on the planet's surface. Here we report observations of HD 189733, the closest of these eclipsing planetary systems, over half an orbital period, from which we can construct a 'map' of the distribution of temperatures. We detected the increase in brightness as the dayside of the planet rotated into view. We estimate a minimum brightness temperature of 973 +/- 33 K and a maximum brightness temperature of 1212 +/- 11 K at a wavelength of 8 microns, indicating that energy from the irradiated dayside is efficiently redistributed throughout the atmosphere, in contrast to a recent claim for another hot Jupiter. Our data indicate that the peak hemisphere-integrated brightness occurs 16$\pm$6 degrees before opposition, corresponding to a hot spot shifted east of the substellar point. The secondary eclipse (when the planet moves behind the star) occurs 120 +/- 24 s later than predicted, which may indicate a slightly eccentric orbit.Comment: To appear in the May 10 2007 issue of Nature, 10 pages, 2 black and white figures, 1 colo

Preventing and lessening exacerbations of asthma in school-age children associated with a new term (PLEASANT) : Study protocol for a cluster randomised control trial

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedBackground: Within the UK, during September, there is a pronounced increase in the number of unscheduled medical contacts by school-aged children (4-16 years) with asthma. It is thought that that this might be caused by the return back to school after the summer holidays, suddenly mixing with other children again and picking up viruses which could affect their asthma. There is also a drop in the number of prescriptions administered in August. It is possible therefore that children might not be taking their medication as they should during the summer contributing to them becoming ill when they return to school. It is hoped that a simple intervention from the GP to parents of children with asthma at the start of the summer holiday period, highlighting the importance of maintaining asthma medication can help prevent increased asthma exacerbation, and unscheduled NHS appointments, following return to school in September.Methods/design: PLEASANT is a cluster randomised trial. A total of 140 General Practices (GPs) will be recruited into the trial; 70 GPs randomised to the intervention and 70 control practices of "usual care" An average practice is expected to have approximately 100 children (aged 4-16 with a diagnosis of asthma) hence observational data will be collected on around 14000 children over a 24-month period. The Clinical Practice Research Datalink will collect all data required for the study which includes diagnostic, prescription and referral data.Discussion: The trial will assess whether the intervention can reduce exacerbation of asthma and unscheduled medical contacts in school-aged children associated with the return to school after the summer holidays. It has the potential to benefit the health and quality of life of children with asthma while also improving the effectiveness of NHS services by reducing NHS use in one of the busiest months of the year. An exploratory health economic analysis will gauge any cost saving associated with the intervention and subsequent impacts on quality of life. If results for the intervention are positive it is hoped that this could be adopted as part of routine care management of childhood asthma in general practice. Trial registration: Current controlled trials: ISRCTN03000938 (assigned 19/10/12) http://www.controlled-trials.com/ISRCTN03000938/.UKCRN ID: 13572.Peer reviewe