An inexpensive, 3D‐printable breast muscle meter for field ornithologists

The size of the pectoral muscle is an important component of body condition in birds and has been linked to indices of fitness and migratory performance. Bauchinger et al. (2011. Journal of Ornithology 152: 507–514) developed, calibrated, and validated an aluminum “muscle meter” device that estimates the size of pectoral muscles noninvasively. To make this tool more widely available, we created a CAD model from 3D‐scan data of the aluminum muscle meter that can be 3D‐printed in durable plastic for ~ $30 USD. We tested this device on seven species of songbirds in Jamaica, The Bahamas, Cameroon, Equatorial Guinea, and Michigan. We demonstrate that the breast muscle meter measurements are (1) repeatable among users, (2) correlated with a four‐category visual breast muscle scoring system, and (3) correlated with scaled mass index (an index of body condition). Muscle scores from our device outperformed the traditional four‐category muscle scoring system in predicting scaled mass index. Finally, with our device, we quantified the increasing breast muscle size of American Redstarts (Setophaga ruticilla) from March through May as they prepared for spring migration. Given the precision of the 3D‐scanning hardware used to generate our 3D image for printing, we produced a plastic muscle meter that is as precise and useful as the aluminum original, but more cost‐effective and widely available.     

A cross-sectional study of pain sensitivity,disease-activity assessment,mental health,and fibromyalgia status in rheumatoid arthritis

IntroductionPain remains the most important problem for people with rheumatoid arthritis (RA). Active inflammatory disease contributes to pain, but pain due to non-inflammatory mechanisms can confound the assessment of disease activity. We hypothesize that augmented pain processing, fibromyalgic features, poorer mental health, and patient-reported 28-joint disease activity score (DAS28) components are associated in RA.MethodsIn total, 50 people with stable, long-standing RA recruited from a rheumatology outpatient clinic were assessed for pain-pressure thresholds (PPTs) at three separate sites (knee, tibia, and sternum), DAS28, fibromyalgia, and mental health status. Multivariable analysis was performed to assess the association between PPT and DAS28 components, DAS28-P (the proportion of DAS28 derived from the patient-reported components of visual analogue score and tender joint count), or fibromyalgia status.ResultsMore-sensitive PPTs at sites over or distant from joints were each associated with greater reported pain, higher patient-reported DAS28 components, and poorer mental health. A high proportion of participants (48%) satisfied classification criteria for fibromyalgia, and fibromyalgia classification or characteristics were each associated with more sensitive PPTs, higher patient-reported DAS28 components, and poorer mental health.ConclusionsWidespread sensitivity to pressure-induced pain, a high prevalence of fibromyalgic features, higher patient-reported DAS28 components, and poorer mental health are all linked in established RA. The increased sensitivity at nonjoint sites (sternum and anterior tibia), as well as over joints, indicates that central mechanisms may contribute to pain sensitivity in RA. The contribution of patient-reported components to high DAS28 should inform decisions on disease-modifying or pain-management approaches in the treatment of RA when inflammation may be well controlled.     

Evaluating spatially explicit viability of a declining ruffed grouse population

Species associated with early successional habitats have experienced dramatic declines in the eastern United States as a result of land use changes and human disruption of natural disturbance regimes. Consequently, active management is required to create early successional habitat and promote plant and animal communities that depend on periodic forest disturbance. Ruffed grouse (Bonasa umbellus) depend on recently disturbed forest habitat, and have experienced dramatic declines over the last half-century. Although ruffed grouse are extensively studied, little effort has been made to link population dynamics with habitat management at landscape scales. We used stochastic, spatially explicit population models that combined landscape conditions derived from a Geographic Information System with demographic data, and applied the model to a declining ruffed grouse population in Rhode Island, USA. We identified vital rates that influence ruffed grouse population dynamics using baseline models constructed with current demographic rates and landscape conditions, and assessed the effect of landscape-scale forest management alternatives on population persistence by running multiple management simulations. Baseline models typically predicted population decline, and we concluded that vital rates (survival and recruitment) had a greater influence on population persistence than did dispersal capability, carrying capacity, or initial population size. Management simulations predicted greater population persistence under a scenario where high-quality habitat was provided in fewer large blocks as opposed to many small blocks, and the rate at which we allowed ruffed grouse to colonize newly created habitat had a substantial impact on management success. Populations of ruffed grouse in the eastern United States are likely to continue to decline given current disturbance regimes, and our work provides a link between ruffed grouse demography and landscape-scale habitat conditions to support management decisions. © 2011 The Wildlife Society.