Feeding behavior of white sharks (Carcharodon carcharias) around a cage diving vessel and the implications for conservation

Honors (Bachelor's)Ecology and Evolutionary BiologyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/107779/1/bromilam.pd

Seagrass Survivor. Subjects: Life Science / Biology, Environmental Science, Marine / Ocean Science Grades: 6-8

This role-play and decision-making game allows students to simulate predator-prey interactions between fish and blue crabs in a seagrass bed. Students will then make inferences about the influence of habitat and body size on juvenile blue crab survival

Digesting Data - Subjects: Life Science / Biology Grade Level: 6-8

This lesson plan encourages students to become scientific investigators to determine which fish species are important predators of juvenile blue crabs in Chesapeake Bay. Students will have the opportunity to practice using triple-beam balances and draw conclusions based on their data

Printing the Ties that Bind

This book brings together essays from scholars working on the first century of French print culture, with a particular focus on the networks formed by authors, editors, translators and printers in the earliest years of print technology. The volume is structured around the themes of collection and translation. The first part of the book examines the gathering of sources, the creation of anthologies and collections and the efforts of collectors to create a legacy. The second part deals with translation and the ways in which editors present a text to a new audience, either in a different language, as part of a different culture or through images that translate the text visually. Together, the essays raise important questions about early modern French culture, revealing how texts are the products both of the networks that create them and of those that distribute, read and interpret them after publication

Medical Education In South Africa

A CAJM article on the training of health personnel in South Africa.The object of medical education is to provide men and women trained to a standard adequate to meet the needs of a medical service to the community which it serves. In a young country like South Africa it is relatively easy to study the development of medical education over the last 200 years. It is without embarrassment that I must point out j that the early history of medical education in >' South Africa is virtually the history of the establishment of the Faculty of Medicine in the University of Cape Town

Juvenile Blue Crab Survival in Nursery Habitats: Predator Identification and Predation Impacts in Chesapeake Bay

Predator populations can have significant impacts on prey recruitment success and prey population dynamics through consumption. Young, inexperienced prey are often most vulnerable to predation due to their small size and limited evasion capabilities. to reduce the risk of predation, new recruits and young juveniles typically settle in structured nursery habitats, such as seagrass beds, which promote higher survival by acting as refuges from predators. Thus, successful recruitment to the adult portion of the population is often dependent on the availability of suitable nursery habitat. In this thesis, I used field tethering experiments and gut content analyses to assess the role of habitat, body size, finfish predation, and cannibalism on the survival of one of the most ecologically and economically important species in Chesapeake Bay: the blue crab Callinectes sapidus. In field tethering experiments, survival probability of juvenile blue crabs in York River nursery habitats (i.e. seagrass beds, sand flats) increased significantly and additively with crab size and SAV cover. Images of predation events during tethering experiments revealed cannibalism by adult blue crabs to be a major source of juvenile mortality. Gut content analyses from three field studies identified seven predators of juvenile blue crabs in lower Chesapeake Bay nursery habitats: adult blue crabs, striped bass Morone saxatilis, red drum Sciaenops ocellatus, silver perch Bairdiella chrysoura, weakfish Cynoscion regalis, Atlantic croaker Micropogonias undulatus, and oyster toadfish Opsanus tau. Using frequency of consumption and diet proportion metrics, I determined striped bass, red drum, and silver perch to be the most impactful finfish predators on juvenile mortality, in addition to cannibalism. Atlantic croaker and oyster toadfish play minor roles in juvenile mortality in Chesapeake Bay nursery habitats. The probability of juvenile crabs being present in a predator’s gut was also significantly higher in seagrass beds than in unvegetated sand flats. Food web dynamics are an important aspect of ecosystem-based fisheries management. Understanding the ecological interactions between populations, and their environment, can provide insight into natural population fluctuations of valuable fishery species such as the blue crab. This thesis demonstrated the positive effects of body size and SAV cover on juvenile crab survival, indicating the importance of seagrass nursery habitat for blue crab population dynamics in Chesapeake Bay. However, despite the predator refuge offered by SAV, high densities of predators and prey in seagrass beds resulted in greater consumption of juveniles in those habitats. Key predators of juvenile blue crabs were also identified and their relative impacts were estimated. The predator-prey relationships revealed in this thesis were integrated into a revised food web for blue crabs in Chesapeake Bay, in the hopes of informing future ecosystem-based management efforts

New liquid chromatographic methods for the analysis of cationic tensides

Cationic tensides are important oleochemicals that are used to prevent adulteration of pharmaceutical preparations and personal care products, as well as being the conditioning agents in domestic fabric softeners. The widespread use of these materials requires quantitative methods for characterising them in raw materials and fully formulated products, whilst "down-the-drain" release necessitates similar methods for trace environmental analysis. Unfortunately, current methods used to quantify cationic tensides are generally non-specific, problematic, or are ill-suited to environmental analysis. There is currently no generic method that can be applied to the quantitation of these materials in all necessary matrices. The aim of this work was to develop new liquid chromatographic (LC) methods for the analysis of the cationic preservative and fabric conditioner actives, before attempting to build the foundations of generic cationic tenside analysis. The development of a new normal phase LC method is reported for the quantitation of the cationic actives present in domestic fabric conditioners. The method yielded high resolution and repeatability, and allowed the quantitation of the homologues endemic in commercial samples. Subsequent hyphenation with mass spectrometry demonstrated the potential for the quantitation of these materials in environmental matrices. -The optimisation and validation of a reverse phase LC method for the analysis of cationic tenside preservatives is reported. Excellent repeatability and resolution were again attained, whilst the new method was also found to demonstrate the inherent sensitivity required for trace environmental analysis. Subsequent hyphenation unfortunately showed that method sensitivity was compromised by ion-suppression, highlighting the need for compromise in the development of LC/MS methods. For both methods, stationary and mobile phase parameters were varied to assess the influence on analyte resolution, and also to gauge the potential for developing a generic liquid chromatographic method for the analysis of these materials. It was observed that many of the commonly held beliefs on the analysis of cationic tensides by reverse phase LC were misconceived. As a result, new insights were made into cationic tenside analysis, which should facilitate the development of a generic LC method applicable to the quantitation of cationic tensides and their hydrophilic biodegradation products in the future

Mechanisms governing ontogenetic habitat shifts: role of trade-offs, predation, and cannibalism for the blue crab

Nursery habitats play a major role in the population dynamics of marine and estuarine species, with the blue crab Callinectes sapidus serving as a model invertebrate. The current paradigm of blue crab habitat use postulates that juvenile survival decreases with size in submerged aquatic vegetation (SAV) due to a reduction in suitably scaled refuge, triggering an ontogenetic shift from SAV to unvegetated habitats. However, alternative mechanisms for this habitat shift have not been examined. We evaluated the paradigm of blue crab habitat use by conducting field tethering experiments in York River (Virginia, USA) nursery habitats using a broad range of juvenile size and SAV cover. Cameras were deployed to identify key predators of juvenile blue crabs and to assess the relative importance of predation and cannibalism as sources of juvenile mortality. Probability of survival increased significantly and additively with crab size and SAV cover. The absence of an interaction between crab size and SAV cover is inconsistent with the current paradigm. Rather, the ontogenetic habitat shift by juvenile blue crabs is likely driven by a density-dependent trade-off between predation risk and foraging efficiency. In images of predation events, adult blue crabs, northern puffers Sphoeroides maculatus, striped burrfish Chilomycterus schoepfi, and oyster toadfish Opsanus tau were identified as predators of juveniles in seagrass beds and sand flats. The high frequency of successful predation events by adult blue crabs suggests that cannibalism is an important source of juvenile mortality and may be as, or more influential, to blue crab population dynamics than finfish predation

The practical management of emergencies in primary care: Taking simulation out of the classroom and into real-life environments

Life threatening emergencies in the community are relatively infrequent and therefore provide a challenge for doctors in keeping up-to-date and maintaining confidence. Training in managing emergencies typically takes place through role play and classroom based simulation. In this project, we took simulation out of the classroom and into community environments where emergencies actually occur creating 'real-life' scenarios. These included the practical management of meningitis, anaphylaxis, hypoglycaemia, convulsions and cardiac arrest. Doctors had to find and utilize the equipment in their surgeries and were asked to physically draw up the appropriate medication. The simulation training was led by a GP and a Consultant in Intensive Care Medicine. Participants' confidence in managing emergencies significantly increased after the workshops. Qualitative feedback illustrated the need for more simulation based learning: "I hope this can be done regularly as it will make a huge difference to patient care", "Excellent - life like to make more memorable", "Good to use the actual surgery equipment". Many of the participants knew the theory of what to do but lacked the practical skills to efficiently manage emergency scenarios. Training doctors through simulation needs to be taken out of the classroom and into real life environments. This is particularly important for 'time critical illnesses' where delays can have a direct impact on morbidity and mortality