ENVIRONMENTAL AND BIOLOGICAL EFFECTS ON NUTRITIONAL MODE AND RESOURCE PARTITIONING IN SCLERACTINIAN CORALS

Ph.D

The economic performance of cities: a Markov-switching approach

This paper examines the determinants of employment growth in metro areas. To obtain growth rates, we use a Markov-switching model that separates a city’s growth path into two distinct phases (high and low), each with its own growth rate. The simple average growth rate over some period is, therefore, the weighted average of the high-phase and low-phase growth rates, with the weight being the frequency of the two phases. We estimate the effects of a variety of factors separately for the high-phase and low-phase growth rates, along with the frequency of the low phase. We find that growth in the high phase is related to human capital, industry mix, and average firm size. In contrast, we find that growth in the low phase is mostly related to industry mix, specifically, the relative importance of manufacturing. Finally, the frequency of the low phase appears to be related to the level of non-education human capital, but to none of the other variables. Overall, our results strongly reject the notion that city-level characteristics influence employment growth equally across the phases of the business cycle.Business cycles ; Cities and towns

Human Granulocytic Ehrlichiosis Complicating Early Pregnancy

Background. The goal of this case is to review the zoonotic infection, human granulocytic ehrlichiosis, presenting with pyrexia. Case. A 22-year-old multigravid female presented to the emergency department with a painful skin rash, high fever, and severe myalgias. The patient underwent a diagnostic evaluation for zoonotic infections due to her geographical and seasonal risk factors. Treatment of human granulocytic ehrlichiosis was successful though the patient spontaneously aborted presumably due to the severity of the acute illness. Conclusion. Treatment of human granulocytic ehrlichiosis in pregnancy presents unique challenges. Management of pyrexia during pregnancy is limited to external cooling in the setting of thrombocytopenia and elevated aminotransferases. Extensive counseling regarding teratogenic potential of medications allows the patient to weigh the pros and cons of treatment

Ticks infesting domestic dogs in the UK:a large-scale surveillance programme

Background: Recent changes in the distribution of tick vectors and the incidence of tick-borne disease, driven variously by factors such as climate change, habitat modification, increasing host abundance and the increased movement of people and animals, highlight the importance of ongoing, active surveillance. This paper documents the results of a large-scale survey of tick abundance on dogs presented to veterinary practices in the UK, using a participatory approach that allows relatively cost- and time-effective extensive data collection. Methods: Over a period of 16 weeks (April-July 2015), 1094 veterinary practices were recruited to monitor tick attachment to dogs and provided with a tick collection and submission protocol. Recruitment was encouraged through a national publicity and communication initiative. Participating practices were asked to select five dogs at random each week and undertake a thorough, standardized examination of each dog for ticks. The clinical history and any ticks were then sent to the investigators for identification. Results: A total of 12,000 and 96 dogs were examined and 6555 tick samples from infested dogs were received. Ixodes ricinus (Linnaeus) was identified on 5265 dogs (89 %), Ixodes hexagonus Leach on 577 (9.8 %) and Ixodes canisuga Johnston on 46 (0.8 %). Ten dogs had Dermacentor reticulatus (Fabricius), one had Dermacentor variabilis (Say), three had Haemaphysalis punctata Canesteini & Fanzago and 13 had Rhipicephalus sanguineus Latreille. 640 ticks were too damaged for identification. All the R. sanguineus and the single D. variabilis were on dogs with a recent history of travel outside the UK. The overall prevalence of tick attachment was 30 % (range 28-32 %). The relatively high prevalence recorded is likely to have been inflated by the method of participant recruitment. Conclusion: The data presented provide a comprehensive spatial understanding of tick distribution and species abundance in the UK against which future changes can be compared. Relative prevalence maps show the highest rates in Scotland and south west England providing a valuable guide to tick-bite risk in the UK

The Mismatch in Distributions of Vertebrates and the Plants that they Disperse

© 2018 The Authors Little is known about how mutualistic interactions affect the distribution of species richness on broad geographic scales. Because mutualism positively affects the fitness of all species involved in the interaction, one hypothesis is that the richness of species involved should be positively correlated across their range, especially for obligate relationships. Alternatively, if mutualisms involve multiple mutualistic partners, the distribution of mutualists should not necessarily be related, and patterns in species distributions might be more strongly correlated with environmental factors. In this study, we compared the distributions of plants and vertebrate animals involved in seed-dispersal mutualisms across the United States and Canada. We compiled geographic distributions of plants dispersed by frugivores and scatter-hoarding animals, and compared their distribution of richness to the distribution in disperser richness. We found that the distribution of animal dispersers shows a negative relationship to the distribution of the plants that they disperse, and this is true whether the plants dispersed by frugivores or scatter-hoarders are considered separately or combined. In fact, the mismatch in species richness between plants and the animals that disperse their seeds is dramatic, with plants species richness greatest in the in the eastern United States and the animal species richness greatest in the southwest United States. Environmental factors were corelated with the difference in the distribution of plants and their animal mutualists and likely are more important in the distribution of both plants and animals. This study is the first to describe the broad-scale distribution of seed-dispersing vertebrates and compare the distributions to the plants they disperse. With these data, we can now identify locations that warrant further study to understand the factors that influence the distribution of the plants and animals involved in these mutualisms

Pancreatectomy for non-pancreatic malignancies results in improved survival after R0 resection

<p>Abstract</p> <p>Background</p> <p>Pancreatectomy has a high morbidity but remains the only chance of cure for pancreatic cancer. Its efficacy for non-pancreatic malignancies is less clear. We reviewed our experience with pancreatectomy for non-pancreatic malignancies to determine outcomes and identify predictors of survival.</p> <p>Patients and methods</p> <p>The records of patients who underwent pancreatectomy for non-pancreatic malignancies between 1990 and 2005 were reviewed. Survival curves were constructed using the Kaplan-Meier method and compared using log-rank analysis. Cox proportional hazards was used to identify predictors of survival.</p> <p>Results</p> <p>29 patients (18 M/11 F) with a mean age of 59.9 years (range 29–86) underwent pancreatectomy for non-pancreatic malignancies. 19 (66%) primary malignancies were GI in origin. Most operations were undertaken with curative intent (76%), whereas the remainder was for symptom palliation. Pancreatectomy was completed for metastatic disease in 7 patients (24%) or en bloc to achieve negative margins in 22 patients (76%). Complete (i.e., R0) resection was achieved in 17 (59%). Perioperative mortality was 3%. Median follow-up was 15 months (range 7–172). Median overall survival was 12 months with 1-year survival of 48%. Significant predictors of improved survival by univariate analysis were R0 resection, non-GI primary, and pancreatic metastasectomy (vs. en bloc resection). Only R0 resection was predictive of long-term survival by multivariate analysis (median 21 months vs. 6).</p> <p>Conclusion</p> <p>Pancreatic resection for non-pancreatic malignancies can be completed with minimal mortality. However, incomplete resection results in poor overall survival. Pancreatectomy for non-pancreatic malignancies should only be undertaken if complete resection is possible.</p

Hyperthermic Fatigue Precedes a Rapid Reduction in Serum Sodium in an Ironman Triathlete: A Case Report

Purpose: To monitor the hydration, core temperature, and speed (pace) of a triathlete performing an Ironman triathlon. Methods: A 35-year-old experienced male triathlete participated in the Western Australian Ironman triathlon on December 1, 2006. The participant was monitored for blood Na+ concentration before the race (PRE), at the transitions (T1 and T2), halfway through the run (R21), and after the race (POST; 2hPOST). Core body temperature (Tc; pill telemetry) was recorded continuously, and running speed (s3 stride sensor) was measured during the run. Results: The participant completed the race in 11 h 38 min, in hot conditions (26.6 ± 5.8°C; 42 ± 19% rel. humidity). His Tc increased from 37.0 to 38.6°C during the 57-min swim, and averaged 38.4°C during the 335-min bike (33.5 km·h−1). After running at 12.4 km·h−1 for 50 min in the heat (33.1°C), Tc increased to 39.4°C, before slowing to 10.0 km·h−1 for 20 min. Tc decreased to 38.9°C until he experienced severe leg cramps, after which speed diminished to 6 km·h−1 and Tc fell to 38.0°C. The athlete’s blood Na+ was constant from PRE to T2 (139–140 mEq·L−1, but fell to 131 mEq·L−1 at R21, 133 mEq·L−1 at POST, and 128 mEq·L−1 at 2hPOST. The athlete consumed 9.25 L of fluid from PRE to T2, 6.25 L from T2 to POST, and lost 2% of his body mass, indicating sweat losses greater than 15.5 L. Conclusion: This athlete slowed during the run phase following attainment of a critically high Tc and experienced an unusually rapid reduction in blood Na+ that preceded cramping, despite presenting with signs of dehydration