Genotype-environment associations support a mosaic hybrid zone between two tidal marsh birds

Local environmental features can shape hybrid zone dynamics when hybrids are bounded by ecotones or when patchily distributed habitat types lead to a corresponding mosaic of genotypes. We investigated the role of marsh-level characteristics in shaping a hybrid zone between two recently diverged avian taxa – Saltmarsh (Ammodramus caudacutus) and Nelson\u27s (A. nelsoni) sparrows. These species occupy different niches where allopatric, with caudacutus restricted to coastal marshes and nelsoni found in a broader array of wetland and grassland habitats and co-occur in tidal marshes in sympatry. We determined the influence of habitat types on the distribution of pure and hybrid sparrows and assessed the degree of overlap in the ecological niche of each taxon. To do this, we sampled and genotyped 305 sparrows from 34 marshes across the hybrid zone and from adjacent regions. We used linear regression to test for associations between marsh characteristics and the distribution of pure and admixed sparrows. We found a positive correlation between genotype and environmental variables with a patchy distribution of genotypes and habitats across the hybrid zone. Ecological niche models suggest that the hybrid niche was more similar to that of A. nelsoni and habitat suitability was influenced strongly by distance from coastline. Our results support a mosaic model of hybrid zone maintenance, suggesting a role for local environmental features in shaping the distribution and frequency of pure species and hybrids across space

Genotype-environment associations support a mosaic hybrid zone between two tidal marsh birds

Local environmental features can shape hybrid zone dynamics when hybrids are bounded by ecotones or when patchily distributed habitat types lead to a corresponding mosaic of genotypes. We investigated the role of marsh-level characteristics in shaping a hybrid zone between two recently diverged avian taxa – Saltmarsh (Ammodramus caudacutus) and Nelson\u27s (A. nelsoni) sparrows. These species occupy different niches where allopatric, with caudacutus restricted to coastal marshes and nelsoni found in a broader array of wetland and grassland habitats and co-occur in tidal marshes in sympatry. We determined the influence of habitat types on the distribution of pure and hybrid sparrows and assessed the degree of overlap in the ecological niche of each taxon. To do this, we sampled and genotyped 305 sparrows from 34 marshes across the hybrid zone and from adjacent regions. We used linear regression to test for associations between marsh characteristics and the distribution of pure and admixed sparrows. We found a positive correlation between genotype and environmental variables with a patchy distribution of genotypes and habitats across the hybrid zone. Ecological niche models suggest that the hybrid niche was more similar to that of A. nelsoni and habitat suitability was influenced strongly by distance from coastline. Our results support a mosaic model of hybrid zone maintenance, suggesting a role for local environmental features in shaping the distribution and frequency of pure species and hybrids across space

2015 researcher's mini-symposium

Postgraduate researchers from the Faculties of Science, Engineering, Medicine & Surgery and Health Sciences gathered for a forum to present their research interests. The symposium was held in the afternoon of 30 January 2015 in the Engineering Lecture Theatre. The symposium promoted multi-disciplinary networking between various university faculties. Participants were invited based on research topic diversity and gender balance.peer-reviewe

Study of Convective Heat Transfer in Grinding Applied to Tool Carbide

The grinding temperature is of great importance for the quality and integrity of machined cemented carbide tool. Tool edge surfaces may be damaged by softening or being stressed, hardened, burned, or cracked. Former research on grinding temperature prediction often made assumptions to simplify heat convection due to the grinding fluid. However, these simplifying assumptions can sometimes undermine the mathematical relationships between grinding conditions and surface temperature, particularly in low-temperature grinding where fluid convection is most important. This paper is an attempt to provide an improved comprehensive thermal model for the prediction of contact temperatures and for monitoring and control of thermal damage. Based on previous thermal model research, this paper tackles a key element of the thermal model for temperature prediction. It proposes a convective heat transfer model based on the classic theory of turbulent flow passing a plate. Theoretical predictions from the thermal model of turbulent flow developed in this paper are compared with experimental values. Predictions are further compared with values from a previously published laminar flow model. And it is shown that the new model leads to a significant reduction in predicted temperatures. The results suggest that the thermal model for the turbulent flow provides a reasonable estimate of predicted temperature values within the region of the fluid boiling temperature. The estimates appear to be an improvement compared with the laminar flow thermal model. The turbulent flow thermal model is considered to improve estimates of background contact temperatures in grinding cemented carbide

Effects of visual feedback on orthopaedic rehabilitation

Currently, functional outcome following total knee arthroplasty (TKA) is not fully restored, with the majority of TKA patients exhibiting lower functional outcome scores than their healthy counterparts [1]. A contributing factor to limited functional outcome may be the nature of the rehabilitation provided as there is still some controversy regarding the most appropriate methods for rehabilitation delivery [2]. Providing patients with visual feedback during rehabilitation has had a positive effect in other patient populations such as stroke survivors [3] and therefore may also improve the efficacy of orthopaedic rehabilitation. The aim of this study was to develop a visual feedback tool based on real time data from 3D motion capture for routine clinical use. Further aims included determining if provision of augmented feedback was acceptable to patients and whether it had a positive effect on functional outcome. Visual feedback using motion analysis was successfully delivered in a routine clinical environment and was widely acceptable to patients. Further, provision of visual feedback appeared to lead to improved knee range of motion in the sagittal plane in comparison to control patients. However, larger scale studies are required to confirm these positive effects

Incidence and Prevalence of Chronic Obstructive Pulmonary Disease among Aboriginal Peoples in Alberta, Canada

Background Chronic obstructive pulmonary disease (COPD) is a major respiratory disorder, largely caused by smoking that has been linked with large health inequalities worldwide. There are important gaps in our knowledge about how COPD affects Aboriginal peoples. This retrospective cohort study assessed the epidemiology of COPD in a cohort of Aboriginal peoples relative to a non-Aboriginal cohort. Methods We used linkage of administrative health databases in Alberta (Canada) from April 1, 2002 to March 31, 2010 to compare the annual prevalence, and the incidence rates of COPD between Aboriginal and non-Aboriginal cohorts aged 35 years and older. Poisson regression models adjusted the analysis for important sociodemographic factors. Results Compared to a non-Aboriginal cohort, prevalence estimates of COPD from 2002 to 2010 were 2.3 to 2.4 times greater among Registered First Nations peoples, followed by the Inuit (1.86 to 2.10 times higher) and the Métis (1.59 to 1.67 times higher). All Aboriginal peoples had significantly higher COPD incidence rates than the non-Aboriginal group (incidence rate ratio [IRR]: 2.1; 95% confidence interval [CI]: 1.97, 2.27). COPD incidence rates were higher in First Nation peoples (IRR: 2.37; 95% CI: 2.19, 2.56) followed by Inuit (IRR: 1.92; 95% CI: 1.64, 2.25) and Métis (IRR: 1.49; 95% CI: 1.32, 1.69) groups. Conclusions We found a high burden of COPD among Aboriginal peoples living in Alberta; a province with the third largest Aboriginal population in Canada. Altogether, the three Aboriginal peoples groups have higher prevalence and incidence of COPD compared to a non-Aboriginal cohort. The condition affects the three Aboriginal groups differently; Registered First Nations and Inuit have the highest burden of COPD. Reasons for these differences should be further explored within a framework of social determinants of health to help designing interventions that effectively influence modifiable COPD risk factors in each of the Aboriginal groups

The EVIL-MC Model for Ellipsoidal Variations of Planet-Hosting Stars and Applications to the HAT-P-7 System

We present a new model for Ellipsoidal Variations Induced by a Low-Mass Companion, the EVIL-MC model. We employ several approximations appropriate for planetary systems to substantially increase the computational efficiency of our model relative to more general ellipsoidal variation models and improve upon the accuracy of simpler models. This new approach gives us a unique ability to rapidly and accurately determine planetary system parameters. We use the EVIL-MC model to analyze Kepler Quarter 0-2 (Q0-2) observations of the HAT-P-7 system, an F-type star orbited by a nearly Jupiter-mass companion. Our analysis corroborates previous estimates of the planet-star mass ratio q = (1.10 +/- 0.06) x 10^(-3), and we have revised the planet's dayside brightness temperature to 2680 +10/-20 K. We also find a large difference between the day- and nightside planetary flux, with little nightside emission. Preliminary dynamical+radiative modeling of the atmosphere indicates this result is qualitatively consistent with high altitude absorption of stellar heating. Similar analyses of Kepler and CoRoT photometry of other planets using EVIL-MC will play a key role in providing constraints on the properties of many extrasolar systems, especially given the limited resources for follow-up and characterization of these systems. However, as we highlight, there are important degeneracies between the contributions from ellipsoidal variations and planetary emission and reflection. Consequently, for many of the hottest and brightest Kepler and CoRoT planets, accurate estimates of the planetary emission and reflection, diagnostic of atmospheric heat budgets, will require accurate modeling of the photometric contribution from the stellar ellipsoidal variation.Comment: Accepted to ApJ; minor revisions to original submission; An IDL version of the EVIL-MC model is publicly available at http://www.lpl.arizona.edu/~bjackson/idl_code/index.htm

Deep and Frequent Phenotyping study protocol: an observational study in prodromal Alzheimer's disease.

INTRODUCTION: Recent failures of potential novel therapeutics for Alzheimer's disease (AD) have prompted a drive towards clinical studies in prodromal or preclinical states. However, carrying out clinical trials in early disease stages is extremely challenging-a key reason being the unfeasibility of using classical outcome measures of dementia trials (eg, conversion to dementia) and the lack of validated surrogate measures so early in the disease process. The Deep and Frequent Phenotyping (DFP) study aims to resolve this issue by identifying a set of markers acting as indicators of disease progression in the prodromal phase of disease that could be used as indicative outcome measures in proof-of-concept trials. METHODS AND ANALYSIS: The DFP study is a repeated measures observational study where participants will be recruited through existing parent cohorts, research interested lists/databases, advertisements and memory clinics. Repeated measures of both established (cognition, positron emission tomography (PET) imaging or cerebrospinal fluid (CSF) markers of pathology, structural MRI markers of neurodegeneration) and experimental modalities (functional MRI, magnetoencephalography and/or electroencephalography, gait measurement, ophthalmological and continuous smartphone-based cognitive and other assessments together with experimental CSF, blood, tear and saliva biomarkers) will be performed. We will be recruiting male and female participants aged >60 years with prodromal AD, defined as absence of dementia but with evidence of cognitive impairment together with AD pathology as assessed using PET imaging or CSF biomarkers. Control participants without evidence of AD pathology will be included at a 1:4 ratio. ETHICS AND DISSEMINATION: The study gained favourable ethical opinion from the South Central-Oxford B NHS Research Ethics Committee (REC reference 17/SC/0315; approved on 18 August 2017; amendment 13 February 2018). Data will be shared with the scientific community no more than 1 year following completion of study and data assembly.NIH

Surface Nano-structured Coating for Improved Performance of Axial Piston Pumps

The work starts from the consideration that most of the power losses in a hydraulic pump is due to frictional losses made by the relative motion between moving parts. This fact is particularly true at low operating velocities, when the hydraulic lift effect must be able to maintain a minimum clearance in meatus to limit the volumetric losses. The potential of structured coatings at nanoscale, with super-hydrophobic and oleophobic characteristics, has never been exploited before in an industrial application. The work studies the potential application of nano-coating on piston slippers surface in a real industrial case. The aim is to develop a new industrial solution to increase the energetic efficiency of hydraulic pump used in earthmoving machines. The proposed solution is investigated using a dedicated test bench, designed to reproduce real working conditions of the pump. The results showa reduction of friction coefficient while changing working pressure and rotation velocity

Kepler eclipsing binary stars. VII. the catalogue of eclipsing binaries found in the entire Kepler data set

The primary Kepler Mission provided nearly continuous monitoring of ~200,000 objects with unprecedented photometric precision. We present the final catalog of eclipsing binary systems within the 105 deg2 Kepler field of view. This release incorporates the full extent of the data from the primary mission (Q0-Q17 Data Release). As a result, new systems have been added, additional false positives have been removed, ephemerides and principal parameters have been recomputed, classifications have been revised to rely on analytical models, and eclipse timing variations have been computed for each system. We identify several classes of systems including those that exhibit tertiary eclipse events, systems that show clear evidence of additional bodies, heartbeat systems, systems with changing eclipse depths, and systems exhibiting only one eclipse event over the duration of the mission. We have updated the period and galactic latitude distribution diagrams and included a catalog completeness evaluation. The total number of identified eclipsing and ellipsoidal binary systems in the Kepler field of view has increased to 2878, 1.3% of all observed Kepler targets