The importance of sample size in marine megafauna tagging studies.

Telemetry is a key, widely used tool to understand marine megafauna distribution, habitat use, behavior, and physiology; however, a critical question remains: "How many animals should be tracked to acquire meaningful data sets?" This question has wide-ranging implications including considerations of statistical power, animal ethics, logistics, and cost. While power analyses can inform sample sizes needed for statistical significance, they require some initial data inputs that are often unavailable. To inform the planning of telemetry and biologging studies of marine megafauna where few or no data are available or where resources are limited, we reviewed the types of information that have been obtained in previously published studies using different sample sizes. We considered sample sizes from one to >100 individuals and synthesized empirical findings, detailing the information that can be gathered with increasing sample sizes. We complement this review with simulations, using real data, to show the impact of sample size when trying to address various research questions in movement ecology of marine megafauna. We also highlight the value of collaborative, synthetic studies to enhance sample sizes and broaden the range, scale, and scope of questions that can be answered.

Tracking apex marine predator movements in a dynamic ocean.

Pelagic marine predators face unprecedented challenges and uncertain futures. Overexploitation and climate variability impact the abundance and distribution of top predators in ocean ecosystems. Improved understanding of ecological patterns, evolutionary constraints and ecosystem function is critical for preventing extinctions, loss of biodiversity and disruption of ecosystem services. Recent advances in electronic tagging techniques have provided the capacity to observe the movements and long-distance migrations of animals in relation to ocean processes across a range of ecological scales. Tagging of Pacific Predators, a field programme of the Census of Marine Life, deployed 4,306 tags on 23 species in the North Pacific Ocean, resulting in a tracking data set of unprecedented scale and species diversity that covers 265,386 tracking days from 2000 to 2009. Here we report migration pathways, link ocean features to multispecies hotspots and illustrate niche partitioning within and among congener guilds. Our results indicate that the California Current large marine ecosystem and the North Pacific transition zone attract and retain a diverse assemblage of marine vertebrates. Within the California Current large marine ecosystem, several predator guilds seasonally undertake north-south migrations that may be driven by oceanic processes, species-specific thermal tolerances and shifts in prey distributions. We identify critical habitats across multinational boundaries and show that top predators exploit their environment in predictable ways, providing the foundation for spatial management of large marine ecosystems.

Dive behaviour and foraging effort of female Cape fur seals Arctocephalus pusillus pusillus.

While marine top predators can play a critical role in ecosystem structure and dynamics through their effects on prey populations, how the predators function in this role is often not well understood. In the Benguela region of southern Africa, the Cape fur seal (Arctocephalus pusillus pusillus) population constitutes the largest marine top predator biomass, but little is known of its foraging ecology other than its diet and some preliminary dive records. Dive information was obtained from 32 adult females instrumented with dive recorders at the Kleinsee colony (29°34.17' S, 16°59.80' E) in South Africa during 2006-2008. Most dives were in the depth range of epipelagic prey species (less than 50 m deep) and at night, reflecting the reliance of Cape fur seals on small, vertically migrating, schooling prey. However, most females also performed benthic dives, and benthic diving was prevalent in some individuals. Benthic diving was significantly associated with the frequency with which females exceeded their aerobic dive limit. The greater putative costs of benthic diving highlight the potential detrimental effects to Cape fur seals of well-documented changes in the availability of epipelagic prey species in the Benguela.

Career satisfaction of physical therapy faculty during their pretenure years.

BACKGROUND AND PURPOSE: The purpose of this study was to compile information about and define variables that are influential in the career satisfaction of tenure-track, full-time, physical therapy faculty who have been employed in academia for 5 years or less but who do not yet have tenure. SUBJECTS AND METHODS: An investigator-developed instrument was used to collect the data. The self-report instrument contained 80 items in four categories: demographics, social supports, teaching, and scholarly activity. Questionnaires were sent to junior physical therapy faculty at the 127 physical therapist schools in the United States and Puerto Rico listed by the American Physical Therapy Association in 1993. There were 163 responses to the survey, representing an estimated 85% of the population of junior faculty as defined by this survey. RESULTS: Eighty-three percent of junior faculty surveyed were satisfied with having taken an academic position, despite feelings of loneliness, tenure anxiety, heavy work loads, and the desire for more guidance from colleagues. CONCLUSION AND DISCUSSION: Social and collegial supports such as relationship with senior faculty and experienced colleagues are key elements influencing faculty satisfaction. Information is given that could be utilized by directors and faculty who are planning to guide the professional development of new faculty.

Clinical measurement of head and shoulder posture variables.

A reliable method that is practical for clinical use for measuring head posture in standing has not been demonstrated in the literature. The purposes of this study were: 1) to produce a reliable method for measuring sagittal plane head and shoulder posture that is practical for clinical use and 2) to perform a pilot study to compare means between a nonpatient sample and a sample of people who have a history of recurring cervical pain. A method of measuring sagittal plane postural alignment of the head and shoulder in relationship to the lateral malleolus was developed using a carpenter's tri-square with a line level attached to the horizontal arm and a goniometer with a line level attached to the horizontal arm. Horizontal measures were taken with the tri-square from a vertical reference point to the tragus of the ear, to the shoulder axis, and to the lateral malleolus. Angular measures were taken with the goniometer of C7-tragus with the horizontal and tragus-corner of the eye with the horizontal. A reliability study was performed by two therapists with 15 non-patient subjects. Intraclass correlation coefficients measuring interrater reliability for horizontal and angular measures were as follows: 1) tragus to lateral malleolus: R = .87; 2) shoulder to lateral malleolus: R = .91;3) tragus to shoulder: R = .7;4) angle tragus-eye-horizon: R = .68; and 5) angle C7-tragus-horizon: R = .34. In the pilot study, 41 nonpatient subjects (11 males and 30 females, 20-45 years) and 10 patient subjects with cervical pain (one male and nine females, 23-43 years) were measured. Means calculated for horizontal distances (in cm) were: 1) tragus to lateral malleolus (nonpatients: 8.14; patients: 6.65);2) shoulder to lateral malleolus (nonpatients: 5.47; patients: 5.98); and 3) tragus to shoulder (nonpatients: 2.78; patients: .56). Means calculated for angular measures were: 1) tragus-eye-horizon (nonpatients: 18.78 degrees; patients: 21.57 degrees) and 2) C7-tragus-horizon (nonpatients: 49.34 degrees; patients: 49.43 degrees). No statistically significant differences were found between the two samples in this pilot study using an independent two-sample t test. This study demonstrates a reliable and practical method for taking postural measurements in the clinic and describes a pilot study for comparing a patient and a nonpatient sample.

A distance learning model in a physical therapy curriculum.

In response to the rural health initiative established in 1991, the University of Kentucky has developed an innovative distance learning program of physical therapy instruction that combines classroom lecture and discussion via compressed video technology with laboratory experiences. The authors describe the process of planning, implementing, and evaluating a specific distance learning course in pathomechanics for the professional-level master's-degree physical therapy students at the University of Kentucky. This presentation may serve as a model for teaching distance learning. Descriptions of optimal approaches to preclass preparation, scheduling, course delivery, use of audiovisual aids, use of handout material, and video production are given. Special activities that may enhance or deter the achievement of the learning objectives are outlined, and a problem-solving approach to common problems encountered is presented. An approach to evaluating and comparing course outcomes for the distance learnere is presented. For this particular course, there was no statistically significant difference in the outcome measures utilized to compare the distance learners with the on-site learners.

The chewing robot: a new biologically-inspired way to evaluate dental restorative materials.

This paper presents a novel in vitro dental wear simulator based on 6-6 parallel kinematics to replicate mechanical wear formation on dental materials and components, such as individual teeth, crowns or bridges. The human mandible, guided by a range of passive structures moves with up to six degrees of freedom (DOF). Currently available wear simulators lack the ability to perform these complex chewing movements. In addition simulators are unable to replicate the normal range of chewing forces as they have no control system able to mimic the natural muscle function controlled by the human central nervous system. Such discrepancies between true in vivo and simulated in vitro movements will influence the outcome and reliability of wear studies using such approaches. This paper summarizes the development of a new dynamic jaw simulator based on the kinematics of the human jaw.

Influence of fungicides and irrigation practice on aflatoxin in peantus before digging.

Peanuts grown under dryland conditions where drought stress occurred accumulated more aflatoxin before digging than peanuts grown under irrigation. Kernels became more susceptible to Aspergillus flavus and A. parasiticus invasion when the soil moisture in the pod zone approached levels at which moisture moved from the pod into the soil and the kernel moisture dropped below 31%. Isolation frequencies of these aspergilli from fresh-dug kernels were lowest in 1968 (maximum of 3%). In 1967 and 1969, maximum percentages of 100 and 74, respectively, were noted. Kernel infestation was correlated with degree of aflatoxin contamination. Dryland fresh-dug kernels contained a maximum of 35,800 parts per billion aflatoxin while a maximum of 50 parts per billion was detected in kernels from irrigated plots. In 1969 A. flavus infestation was as high as 59% in peanuts from irrigated plots; however, no aflatoxin was detected. Absence of aflatoxin in these samples is attributed to the higher kernel moisture content which reduced the aflatoxin-producing potential of A. flavus. Statistical analysis of the data revealed no significant differences in degree of fungal infestation, production levels, and grade factors between any fungicide treatments.