859 research outputs found
Social Factors Driving Grouping Dynamics in Bighorn Sheep Ewe
Understanding and predicting movement is critical for conservation planning and disease risk mitigation, and important environmental drivers of animal movement have received extensive attention in the ecological literature. Social factors surrounding group fission and fusion events also directly affect movement. However, these events are infrequently measured in the wild and rarely linked to underlying mechanisms such as relatedness, agreement in reproductive status, or shared life stage. While some social factors cannot be directly observed in the field, individual animals congregating in groups and moving about a landscape can. In animal societies, groups may merge together in a fusion event, and a group may split in a fission event. These events, repeating over time within a population, constitute fission-fusion dynamics. Here, we study group structure and how individuals navigate the social environment that structure imposes, using a long-term, individual-level dataset on female bighorn sheep gathered at the Confederated Salish and Kootenai Tribal (CSKT) Bison Range in Montana, USA. In Chapter 2, we describe three dimensions of fission-fusion dynamics that clarify the context that informs an individual’s social environment: group size, composition, and spatial cohesion in this population. In Chapter 3, we relate these group attributes from the previous chapter to social processes and underlying drivers using a discrete choice model. Our analysis opens a door for understanding how social mechanisms precipitate observed space use behaviors, with implications for how we view animal societies in research. We find that general group-level attributes like group size and demographic makeup along with specific, dyadic social attributes like mother and cohort relationships each influence bighorn sheep group configurations at the Bison Range and drive fission and fusion events
Understanding Interactions Between Butterflies and their Floral Resources in Iowa Grasslands
Grasslands provide habitat for many animal species and serve to improve soil and water quality. These ecosystem services have an impact on humans through economic, health, and aesthetic avenues. Given historic and ongoing losses of grasslands to row crop agriculture and development, it is essential to better understand the complex relationships between grassland animals and their environment in order to conserve and restore grassland habitat. This research focused on improving the understanding of interactions between grassland butterflies and their environment. Topics explored include landscape history and management (with an emphasis on the effect of fire as a management tool), nectar production, flower diversity, and butterfly abundance patterns and behavior. We analyzed butterfly activity in grassland plots as a function of floral resources (nectar volume and concentration). This research was conducted in three grassland types: 1) remnant prairies, 2) reconstructed prairies, and 3) moderately grazed cattle pastures. Within these grasslands, plant diversity and management varied. Flower diversity appears to affect butterfly abundance and behavior, and fire as maintenance is having an effect on nectar resources. This work will provide an improved understanding of the interactions between butterflies and their resources, and it will inform decision-makers interested in managing grasslands for pollinators
Infantile Penis in the Canine
An eleven-month-old intact male Doberman with infantile penis, phimosis, and resultant urine burns to the preputial mucosa was surgically corrected by shortening the prepuce and corecting the phimosis, allowing normal extrusion of the penis on urination
Recombinant interleukin-1β dilates steelhead trout coronary microvessels : effect of temperature and role of the endothelium, nitric oxide and prostaglandins
© 2015. Published by The Company of Biologists Ltd. Acknowledgements We thank Wenjuan Xu and Xin Xu (Hein Lab) for their excellent instruction in microvessel techniques, Dr David Heeley (Biochemistry Department, MUN) for assistance with selecting an appropriate (non-vasoactive) protein stabilizer, Dr Zou (SFIRC, Aberdeen) for advice with regards to the use of rIL-1β and Gordon Nash (Gamperl Lab) for his assistance with the rIL-1β purification protocol. Funding This research was supported by a Natural Sciences and Engineering Research Council of Canada Discovery Grant [RGPIN249926] and Accelerator Supplement [RGPAS412325-2011] to A.K.G. a National Institutes of Health Grant [EY018420] to T.W.H., and a doctoral fellowship from Fundaçã o para a Ciência e a Tecnologia, Portugal [SFRH/BD/27497/2006] to I.A.S.F.C. Deposited in PMC for release after 12 months.Peer reviewedPublisher PD
A Longitudinal Study of Bacterial Contamination in Retail Meats and Meat Products
Beginning in September 1975, and with records continuing through May, 1997, a laboratory class in food safety has been conducted at Iowa State University in 2-week rotations of 6–9 students each. As a component of the class, inspections has been made of local food establishments and a total of 825 meats and meat products have been purchased for microbiological laboratory cultures, with 77.6% positive for total aerobic plate counts, 55.3% positive for fecal coliforms, and 54.9% positive for Staphylococcus aureus. Titers ranged between 102.3 and 107.2 colony forming units (CFU) per gram. Analysis by 5-year periods has identified no progress over the 23 year period in lower prevalence or lower titers of contamination by these bacteria
Survival of Selected Viruses on Processed Pork Products
Contamination of food with viruses of human health significance is primarily due to human carriers. While cooking or fermenting and drying will inactivate viruses, products can be contaminated post-processing. The data show that the changes produced in pork products by processing will have little effect in decreasing viral numbers if post-processing contamination occurs
Cytokine-mediated blood brain barrier disruption as a conduit for cancer/chemotherapy-associated neurotoxicity and cognitive dysfunction
Neurotoxicity is a common side effect of chemotherapy treatment, with unclear molecular mechanisms. Clinical studies suggest that the most frequent neurotoxic adverse events affect memory and learning, attention, concentration, processing speeds and executive function. Emerging preclinical research points toward direct cellular toxicity and induction of neuroinflammation as key drivers of neurotoxicity and subsequent cognitive impairment. Emerging data now show detectable levels of some chemotherapeutic agents within the CNS, indicating potential disruption of blood brain barrier integrity or transport mechanisms. Blood brain barrier disruption is a key aspect of many neurocognitive disorders, particularly those characterized by a proinflammatory state. Importantly, many proinflammatory mediators able to modulate the blood brain barrier are generated by tissues and organs that are targets for chemotherapy-associated toxicities. This review therefore aims to explore the hypothesis that peripherally derived inflammatory cytokines disrupt blood brain barrier permeability, thereby increasing direct access of chemotherapeutic agents into the CNS to facilitate neuroinflammation and central neurotoxicity.Hannah R. Wardill, Kimberley A. Mander, Ysabella Z.A. Van Sebille, Rachel J. Gibson, Richard M. Logan, Joanne M. Bowen, and Stephen T. Soni
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