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Many migratory species are in decline across their geographical ranges. Single‐population studies can provide important insights into drivers at a local scale, but effective conservation requires multi‐population perspectives. This is challenging because relevant data are often hard to consolidate, and state‐of‐the‐art analytical tools are typically tailored to specific datasets.We capitalized on a recent data harmonization initiative (SPI‐Birds) and linked it to a generalized modelling framework to identify the demographic and environmental drivers of large‐scale population decline in migratory pied flycatchers (Ficedula hypoleuca) breeding across Britain.We implemented a generalized integrated population model (IPM) to estimate age‐specific vital rates, including their dependency on environmental conditions, and total and breeding population size of pied flycatchers using long‐term (34–64 years) monitoring data from seven locations representative of the British breeding range. We then quantified the relative contributions of different vital rates and population structure to changes in short‐ and long‐term population growth rate using transient life table response experiments (LTREs).Substantial covariation in population sizes across breeding locations suggested that change was the result of large‐scale drivers. This was supported by LTRE analyses, which attributed past changes in short‐term population growth rates and long‐term population trends primarily to variation in annual survival and dispersal dynamics, which largely act during migration and/or nonbreeding season. Contributions of variation in local reproductive parameters were small in comparison, despite sensitivity to local temperature and rainfall within the breeding period.We show that both short‐ and long‐term population changes of British breeding pied flycatchers are likely linked to factors acting during migration and in nonbreeding areas, where future research should be prioritized. We illustrate the potential of multi‐population analyses for informing management at (inter)national scales and highlight the importance of data standardization, generalized and accessible analytical tools, and reproducible workflows to achieve them. [ABSTRACT FROM AUTHOR]

Background: To describe the 2- to 4-year visual and microperimetry outcomes of autologous retinal pigment epithelium (RPE)-choroid graft in patients with neovascular age-related macular degeneration (AMD). Methods: In this retrospective cohort study, 12 patients with subfoveal neovascular AMD who had undergone autologous RPE-choroid graft between August 2004 and June 2005 were reviewed. Change in visual acuity (VA), contrast sensitivity (CS), fixation stability and retinal sensitivity on microperimetry after 2–3 years and the rates of late postoperative complications were examined. Results: Patients were followed for 26–48 months (mean, 39). Median preoperative VA (logMAR) was 0.87 but declined to 1.43 (1 year), 1.46 (2 years) and 1.38 (3 years), P = 0.001. Median CS (logCS) was 0.75 preoperatively but declined to 0.45 at 2 years. Six patients had serial microperimetry. Fixation stability declined in 1 but improved in 2 patients. All 6 had decline in retinal sensitivity over the graft during follow up. Retinal detachment did not occur after 12 months but 8 developed epiretinal membrane, 12 had cystic retinal change over the graft and 4 developed recurrent choroidal neovascularization. However, 10 grafts retained autofluorescence signal at 18–48 months of follow up. Conclusions: Autologous RPE-choroid graft can maintain VA, stable fixation and retinal sensitivity in some patients for over 3 years. The spatial correlation between graft autofluorescence, outer retinal structures on optical coherence tomography and retinal sensitivity are consistent with photoreceptor cell rescue. However, we caution the use of this technique as there is high complication rate and delayed loss of retinal function. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the extent of cortical functional preservation following retinal pigment epithelium (RPE) transplantation in the Royal College of Surgeons (RCS) rat using single-wavelength optical imaging and spectroscopy. The cortical responses to visual stimulation in transplanted rats at 6 months post-transplantation were compared with those from age-matched untreated dystrophic and non-dystrophic rats. Our results show that cortical responses were evoked in non-dystrophic rats to both luminance changes and pattern stimulation, whereas no response was found in untreated dystrophic animals to any of the visual stimuli tested. In contrast, a cortical response was elicited in most of the transplanted rats to luminance changes and in many of those a response was also evoked to pattern stimulation. Although the transplanted rats did not respond to high spatial frequency information we found evidence of preservation in the cortical processing of luminance changes and low spatial frequency stimulation. Anatomical sections of transplanted rat retinas confirmed the capacity of RPE transplantation to rescue photoreceptors. Good correlation was found between photoreceptor survival and the extent of cortical function preservation determined with optical imaging techniques. This study determined the efficacy of RPE transplantation to preserve visual cortical processing and established optical imaging as a powerful technique for its assessment. [ABSTRACT FROM AUTHOR]

Investigates the status of the European Economic Community (EEC) monetary policy. Criticisms against the lack of move by the EEC to enact a regional unit of currency and capital market; Provisions of the Community's Barbe Plan.

The article offers information on the Cooperative Extension (CE) as a partnership between land-grant universities and the U.S. Department of Agriculture (USDA) in 2018. CE comprises of a network of educators, outreach professionals and publicly engaged scientists with the extension and interdisciplinary research efforts spanning human resource, ecological and agricultural fields.

Schwann cells, the myelin-forming glial cells of the peripheral nervous system, wrap around axons to form multiple polarized domains that provide electrical insulation of fibers in a manner that ensures rapid saltatory nerve conduction. Here we report expression of the junctional adhesion molecule (JAM)-C in Schwann cells at junctions between adjoining myelin lamellae and demonstrate that its absence in JAM-C deficient mice results in loss of integrity of the myelin sheath in ∼20% of axonal fibers. In line with this finding, JAM-C deficiency led to defective nerve conductance (100% and 34% reduction after stimulation at 5V and 10V, respectively) and behavioral abnormalities (17% and 20% reduction in stride lengths and grip strength assays, respectively). These results suggest that JAM-C plays an important role in maintaining the structural integrity of myelin sheaths, a finding that provides novel insight to the pathogenesis of peripheral neuropathies. [ABSTRACT FROM AUTHOR]