An Analysis of Potential Parallel Evolution between Two Spatial Scales of Balsam Poplar, Populus balsamifera

Local adaptation to climate provides strong evidence for the operation of natural selection. When climate gradients are shared, there is a potential for parallelism of local adaptation. By studying this potential parallelism, we gain insight into the balance between natural selection and gene flow operating within a given system. Here, I explore the idea of potential parallel evolution of local adaptation between a broad spatial scale and a fine spatial scale within Populus balsamifera. To do this, we grew trees from both spatial scales in a common garden and measured selected bud phenology traits (growing season length, bud set, bud flush, and leaf flush). These traits were first analyzed with linear mixed models to determine if there were significant clinal relationships between traits and source climate. Then the models of broad spatial scale individuals were used to predict trait values for the fine spatial scale individuals to determine if broad-scale relationships can accurately predict those of the fine scale. The results showed significant clinal relationships for the broad scale, but not for the fine scale. These broad-scale relationships successfully estimated the trait values of the fine scale but often left considerable variation unexplained. These results suggest that at the broad scale, there is a clinal relationship between phenology and source climate. The fine-scale individuals fall within this trend; however, they show no relationship of their own. Thus, selection is able to overcome the homogenizing effects of gene flow at broad spatial scales, but at fine spatial scales, the strength of gene flow cannot be overcome by selection. This study provides new insight into the evolutionary drivers operating at these spatial scales within P. balsamifera

Cognitive loading affects motor awareness and movement kinematics but not locomotor trajectories during goal-directed walking in a virtual reality environment.

The primary purpose of this study was to investigate the effects of cognitive loading on movement kinematics and trajectory formation during goal-directed walking in a virtual reality (VR) environment. The secondary objective was to measure how participants corrected their trajectories for perturbed feedback and how participants' awareness of such perturbations changed under cognitive loading. We asked 14 healthy young adults to walk towards four different target locations in a VR environment while their movements were tracked and played back in real-time on a large projection screen. In 75% of all trials we introduced angular deviations of ±5° to ±30° between the veridical walking trajectory and the visual feedback. Participants performed a second experimental block under cognitive load (serial-7 subtraction, counter-balanced across participants). We measured walking kinematics (joint-angles, velocity profiles) and motor performance (end-point-compensation, trajectory-deviations). Motor awareness was determined by asking participants to rate the veracity of the feedback after every trial. In-line with previous findings in natural settings, participants displayed stereotypical walking trajectories in a VR environment. Our results extend these findings as they demonstrate that taxing cognitive resources did not affect trajectory formation and deviations although it interfered with the participants' movement kinematics, in particular walking velocity. Additionally, we report that motor awareness was selectively impaired by the secondary task in trials with high perceptual uncertainty. Compared with data on eye and arm movements our findings lend support to the hypothesis that the central nervous system (CNS) uses common mechanisms to govern goal-directed movements, including locomotion. We discuss our results with respect to the use of VR methods in gait control and rehabilitation

Use of Motor Abundance in Young and Older Adults during Dual-Task Treadmill Walking

Contains fulltext : 110120.pdf (publisher's version ) (Open Access)Motor abundance allows individuals to perform any task reliably while being variable in movement's particulars. The study investigated age-related differences in this feature when young adults (YA) and older adults (OA) performed challenging tasks, namely treadmill walking alone and while performing a cognitive task. A goal function for treadmill walking was first defined, i.e., maintain constant speed at each step, which led to a goal equivalent manifold (GEM) containing all combinations of step time and step length that equally satisfied the function. Given the GEM, amounts of goal-equivalent and non-goal-equivalent variability were afterwards determined and used to define an index providing information about the set of effective motor solutions relative to the GEM. The set was limited in OA compared to YA in treadmill walking alone, indicating that OA made less flexible use of motor abundance than YA. However, this differentiation between YA and OA disappeared when concurrently performing the cognitive task. It is proposed that OA might have benefited from cognitive compensation

Impact of immunogenicity on clinical efficacy and toxicity profile of biologic agents used for treatment of inflammatory arthritis in children compared to adults

The treatment of inflammatory arthritis has been revolutionised by the introduction of biologic treatments. Many biologic agents are currently licensed for use in both paediatric and adult patients with inflammatory arthritis and contribute to improved disease outcomes compared with the pre-biologic era. However, immunogenicity to biologic agents, characterised by an immune reaction leading to the production of anti-drug antibodies (ADAs), can negatively impact the therapeutic efficacy of biologic drugs and induce side effects to treatment. This review explores for the first time the impact of immunogenicity against all licensed biologic treatments currently used in inflammatory arthritis across age, and will examine any significant differences between ADA prevalence, titres and timing of development, as well as ADA impact on therapeutic drug levels, clinical efficacy and side effects between paediatric and adult patients. In addition, we will investigate factors associated with differences in immunogenicity across biologic agents used in inflammatory arthritis, and their potential therapeutic implications

Moving to capture children’s attention: developing a methodology for measuring visuomotor attention

Attention underpins many activities integral to a child’s development. However, methodological limitations currently make large-scale assessment of children’s attentional skill impractical, costly and lacking in ecological validity. Consequently we developed a measure of ‘Visual Motor Attention’ (VMA) - a construct defined as the ability to sustain and adapt visuomotor behaviour in response to task-relevant visual information. In a series of experiments, we evaluated the capability of our method to measure attentional processes and their contributions in guiding visuomotor behaviour. Experiment 1 established the method’s core features (ability to track stimuli moving on a tablet-computer screen with a hand-held stylus) and demonstrated its sensitivity to principled manipulations in adults’ attentional load. Experiment 2 standardised a format suitable for use with children and showed construct validity by capturing developmental changes in executive attention processes. Experiment 3 tested the hypothesis that children with and without coordination difficulties would show qualitatively different response patterns, finding an interaction between the cognitive and motor factors underpinning responses. Experiment 4 identified associations between VMA performance and existing standardised attention assessments and thereby confirmed convergent validity. These results establish a novel approach to measuring childhood attention that can produce meaningful functional assessments that capture how attention operates in an ecologically valid context (i.e. attention's specific contribution to visuomanual action)

The changing global distribution and prevalence of canine transmissible venereal tumour.

BACKGROUND: The canine transmissible venereal tumour (CTVT) is a contagious cancer that is naturally transmitted between dogs by the allogeneic transfer of living cancer cells during coitus. CTVT first arose several thousand years ago and has been reported in dog populations worldwide; however, its precise distribution patterns and prevalence remain unclear. RESULTS: We analysed historical literature and obtained CTVT prevalence information from 645 veterinarians and animal health workers in 109 countries in order to estimate CTVT's former and current global distribution and prevalence. This analysis confirmed that CTVT is endemic in at least 90 countries worldwide across all inhabited continents. CTVT is estimated to be present at a prevalence of one percent or more in dogs in at least 13 countries in South and Central America as well as in at least 11 countries in Africa and 8 countries in Asia. In the United States and Australia, CTVT was reported to be endemic only in remote indigenous communities. Comparison of current and historical reports of CTVT indicated that its prevalence has declined in Northern Europe, possibly due to changes in dog control laws during the nineteenth and twentieth centuries. Analysis of factors influencing CTVT prevalence showed that presence of free-roaming dogs was associated with increased CTVT prevalence, while dog spaying and neutering were associated with reduced CTVT prevalence. Our analysis indicated no gender bias for CTVT and we found no evidence that animals with CTVT frequently harbour concurrent infectious diseases. Vincristine was widely reported to be the most effective therapy for CTVT. CONCLUSIONS: Our results provide a survey of the current global distribution of CTVT, confirming that CTVT is endemic in at least 90 countries worldwide. Additionally, our analysis highlights factors that continue to modify CTVT's prevalence around the world and implicates free-roaming dogs as a reservoir for the disease. Our analysis also documents the disappearance of the disease from the United Kingdom during the twentieth century, which appears to have been an unintentional result of the introduction of dog control policies.This is the author's accepted manuscript. The final version of this article has been published by BioMed Central: http://www.biomedcentral.com/1746-6148/10/168

Is age a barrier to chemotherapy? Rates of treatment in older patients with breast, colon or lung cancer in England in 2014: A national registry study

Background Survival from cancer in older patients is poorer in the UK than other countries with similar health systems and wealth possibly due to undertreatment and increased toxicities in this specific population. This population-based observational study describes factors affecting systemic anticancer treatment (SACT) use in older patients in England. Methods We identified patients aged ≥70 with stage II-III breast cancer, stage III colon cancer and stage IIIB-IV non-small cell lung cancer (NSCLC) diagnosed in 2014 from a dataset collected by the National Health Service in England. We used logistic regression to estimate factors affecting likelihood of receiving SACT and performed separate regression analyses for each disease, adjusting for age, gender, stage at diagnosis, pathological features, performance status, Charlson comorbidity index, ethnicity and socioeconomic group. We assessed 2-year overall survival (OS) using Kaplan-Meier method. Case mix adjusted treatment rates and workload volume were calculated at hospital level and presented using funnel plots, stratified by age groups (<70 and ≥70) to allow for assessment of variation between centres. Results 36892 patients were identified: 19879 with stage II-III breast cancer, 5292 with stage III colon cancer and 11721 with stage IIIB-IV NSCLC. Patients over 70 were less likely to receive SACT compared to those aged under 70: breast 11.7% vs 64.6%, p < 0.001; colon 37.4% vs 79%, p < 0.001; NSCLC 33.5% vs 60.2%, p < 0.001. 2-year OS for patients receiving SACT was similar for patients aged ≥70 and <70: breast 91.5% (95% CI: 89.3%-93.2%) vs 96.4% (95% CI: 95.9%-96.7%); colon 84.8% (95% CI: 82.6%-86.8%) vs 88.3% (95% CI: 86.7%-89.8%); NSCLC 16.7% (95% CI: 15.1%-18.4%) vs 19.8% (95%CI: 18.5%-21.1%). Patients receiving SACT had better OS than those untreated. SACT rates varied widely between hospitals after adjusting for case-mix across all ages. Conclusions Our study suggests that several factors affect the likelihood of receiving SACT but after adjusting for these, age remains determinant. Identifying hospitals with significantly lower SACT rates should prompt local review of multidisciplinary team practice

A genome assembly of the American black bear, Ursus americanus, from California

The American black bear, Ursus americanus, is a widespread and ecologically important species in North America. In California, the black bear plays an important role in a variety of ecosystems and serves as an important species for recreational hunting. While research suggests that the populations in California are currently healthy, continued monitoring is critical, with genomic analyses providing an important surveillance tool. Here we report a high-quality, near chromosome-level genome assembly from a U. americanus sample from California. The primary assembly has a total length of 2.5 Gb contained in 316 scaffolds, a contig N50 of 58.9 Mb, a scaffold N50 of 67.6 Mb, and a BUSCO completeness score of 96%. This U. americanus genome assembly will provide an important resource for the targeted management of black bear populations in California, with the goal of achieving an appropriate balance between the recreational value of black bears and the maintenance of viable populations. The high quality of this genome assembly will also make it a valuable resource for comparative genomic analyses among black bear populations and among bear species