A Landowner’s Guide to Common North American Predators of Upland-nesting Birds

Predation has been identified as a key factor limiting upland-nesting bird reproductive success in many studies. These results suggest that the effects of predation could be reduced by establishing and maintaining suitable nesting habitats. In several studies, habitat management alone was able to maintain populations of upland-nesting birds at or slightly above threshold believed necessary to sustain populations. However, additional studies also have shown that avian populations increased substantially after predator populations were reduced or nesting birds were protected by restricting predator access through the use of electric fencing or creating nesting islands. These practices, however, need to be implemented in combination with good habitat management if optimum benefits are to be realized

Infinities within graviton scattering amplitudes

We present unitarity as a method for determining the infinities present in graviton scattering amplitudes. The infinities are a combination of IR and UV. By understanding the soft singularities we may extract the UV infinities and relate these to counter-terms in the effective action. As an demonstration of this method we rederive the UV infinities present at one-loop when gravity is coupled to matter.Comment: revised versio

Slow dynamics and aging in a non-randomly frustrated spin system

A simple, non-disordered spin model has been studied in an effort to understand the origin of the precipitous slowing down of dynamics observed in supercooled liquids approaching the glass transition. A combination of Monte Carlo simulations and exact calculations indicates that this model exhibits an entropy vanishing transition accompanied by a rapid divergence of time scales. Measurements of various correlation functions show that the system displays a hierarchy of time scales associated with different degrees of freedom. Extended structures, arising from the frustration in the system, are identified as the source of the slow dynamics. In the simulations, the system falls out of equilibrium at a temperature $T_{g}$ higher than the entropy-vanishing transition temperature and the dynamics below $T_{g}$ exhibits aging as distinct from coarsening. The cooling rate dependence of the energy is also consistent with the usual glass formation scenario.Comment: 41 pages, 16 figures. Bibliography file is correcte

Factors associated with advanced colorectal cancer differ between young and older adults in England: A population-based cohort study

Aim: Advanced stage presentation of colorectal cancer is associated with poorer survival outcomes, particularly among young adults. This study aimed to determine whether demographic risk factors for advanced stage presentation differed between young and older adults.Method: Individual‐level data on all incident colorectal cancers in people aged 20 years and above were extracted from the National Cancer Registration and Analysis Service database for the years 2012 to 2015. Patients were divided into two cohorts: young‐onset colorectal cancer (YOCC) if aged 20–49 years and older‐onset colorectal cancer (OOCC) if aged 50 years and above. Logistic regression was used to identify risk factors for advanced stage presentation, defined as TNM Stage III or IV, in each cohort.Results: There were 7075 (5.2%) patients in the YOCC cohort and 128 345 (94.8%) patients in the OOCC cohort. Tumours in the YOCC cohort were more likely to be at an advanced stage (67.2% vs 55.3%, P < 0.001) and located distally (63.7% vs 55.4%, P < 0.001). No demographic factor was consistently associated with advanced stage presentation in the YOCC cohort. Among the OOCC cohort, increased social deprivation [OR (Index of Multiple Deprivation quintile 5 vs 1) = 1.11 (95% CI 1.07–1.16), P < 0.001], Black/Black British ethnicity [OR (baseline White) = 1.25 (95% CI 1.11–1.40), P < 0.001] and residence in the East Midlands [OR (baseline London) = 1.11 (95% CI 1.04–1.17), P = 0.001] were associated with advanced stage presentation.Conclusion: Demographic factors associated with advanced disease were influenced by age. The effects of social deprivation and ethnicity were only observed in older adults and mirror trends in screening uptake. Targeted interventions for high‐risk groups are warranted