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Mobile information technology is changing the education landscape by offering learners the opportunity to engage in asynchronous, ubiquitous instruction. While there is a proliferation of mobile content management systems being developed for the mobile Web and stand-alone mobile applications, few studies have addressed learner expectations and usage intent in consuming digital documents from online content providers and digital libraries with specific emphasis on formal instruction. Understanding usage intent and actual usage of a mobile learning agent as a result of ease of use and usefulness of mobile devices will be addressed in this study. A research framework for instructional technology usage is proposed to help better articulate critical success factors in implementing formal learning using a mobile device, specifically an electronic reader or a tablet computer.

Fishways designed for salmonids often restrict passage by non-salmonids, and effective tools are needed both to identify passage problems for nontarget species and to inform remediation planning. In this case study, we used migration histories from 2170 radio-tagged adult Pacific lamprey (Entosphenus tridentatus) to identify locations of poor passage (bottlenecks) at a large, multifishway dam. Over 10 years, 49% of tagged lamprey that entered fishways failed to pass the dam. Models accounting for repeated attempts by individual lamprey indicated successful passage strongly depended on attempted passage route. Success also varied with time of fishway entry, water temperature, and lamprey body size. Most failed passage attempts terminated in lower fishway segments, but extensive seasonal shifts in bottleneck locations were detected. Ranking metrics helped prioritize bottlenecks and identified sites where structural or operational modifications should improve lamprey passage. Our integration of spatially intensive monitoring with novel analytical techniques was critical to understanding the complex relationships among fishway features, environmental variation, and lamprey behavior. The prioritization framework can be applied to a wide range of fish passage assessments. Les passes migratoires concues pour les salmonides restreignent souvent le passage d'autres poissons, et des outils efficaces sont necessaires pour cerner les problemes associes au passage d'especes non visees et eclairer la planification de mesures correctives. Dans la presente etude de cas, nous avons utilise les historiques de migration de 2170 lamproies du Pacifique (Entosphenus tridentatus) adultes munies de radio-emetteurs pour cerner les lieux de passage difficiles (goulots d'etranglement) a un important barrage comptant plusieurs passes. Sur une periode de 10 ans, 49% des lamproies munies d'emetteurs qui entraient dans ces passes ne reussissaient pas a remonter le barrage. Des modeles tenant compte de tentatives multiples par les memes lamproies ont indique que le succes du passage dependait fortement de la voie de passage employee. Le taux de succes variait egalement selon le moment de l'entree dans la passe, la temperature de l'eau et la taille du corps de la lamproie. La plupart des tentatives de passage infructueuses prenaient fin dans des sections avals des passes, mais d'importantes variations saisonnieres de l'emplacement des goulots d'etranglement ont ete decelees. Le classement des differents parametres a aide a etablir la priorite des goulets et a cerner les sites ou des modifications structurales ou operationnelles devraient ameliorer le passage des lamproies. L'integration d'une surveillance spatiale fine et de nouvelles techniques analytiques s'est averee essentielle a une meilleure comprehension des liens complexes entre les caracteristiques des passes a poissons, les variations des conditions du milieu et le comportement des lamproies. Le cadre d'etablissement de la priorite peut etre applique a un vaste eventail devaluations de passes a poissons. [Traduit par la Redaction], Introduction River systems worldwide have been fragmented by dams and other anthropogenic obstacles that restrict fish movements (Nilsson et al. 2005). A diverse array of fishways and other passage systems [...]

Pacific lamprey, Lampetra tridentata, has declined precipitously throughout their range in the Columbia River basin of North America. Tribal Nations and Federal and State agencies are engaged in efforts to restore these fish. Understanding whether Pacific lamprey emit and detect migratory pheromones is particularly important for these restoration efforts. Using behavioural assays, we demonstrated that migratory adult Pacific lamprey are attracted to odors emanating from their larval conspecifics. We then identified putative pheromones released by larval Pacific lamprey. Chemical analysis of the conditioned water from larval lamprey using liquid chromatography--mass spectrometry (LC-MS) revealed that the Pacific lamprey can release petromyzonamine disulfate (PADS), petromyzosterol disulfate (PSDS), and petromyzonol sulfate (PZS). Electro-olfactogram studies further demonstrated that adult Pacific lamprey can smell those bile acid compounds. Our data strongly indicate that the Pacific lamprey employ a chemical communication system mediated by a mixture of bile acids, as evidenced by pheromonal functions of the bile acid compounds in guiding migratory adult sea lamprey to the spawning streams. Comprehensive understanding of the chemical communications involved in lamprey migratory behavior may lead to improved scientific approaches for restoration efforts. La lamproie du Pacifique, Lampetra tridentata, a diminue de facon rapide dans l'ensemble de leur aire de repartition dans le bassin du Columbia en Amerique du Nord. Les agences des nations tribales, des etats et du gouvernement federal se sont engagees dans des efforts pour la restauration de ces poissons. Dans ces efforts de restauration, il est particulierement important de connaitre si les lamproies du Pacifique emettent et detectent des pheromones de migration. A l'aide de tests comportementaux, nous avons demontre que les lamproies du Pacifique migratrices sont attirees par les odeurs emises par les larves de leur propre espece. Nous avons ensuite identifie les hormones putatives emises par les larves des lamproies du Pacifique. L'analyse chimique par chromatographie en phase liquide et spectrometrie de masse (LC-MS) de l'eau conditionnee par les larves de lamproies montre que les lamproies du Pacifique peuvent emettre du bisulfate de petromyzonamine (PADS), du bisulfate de petromyzosterol (PSDS) et du sulfate de petromyzonol (PZS). Des l'electroolfactogrammes demontrent en plus que les lamproies du Pacifique adultes peuvent sentir ces composes d'acides biliaires. Nos donnees indiquent clairement que la lamproie du Pacifique utilise un systeme de communication chimique par l'intermediaire d'un melange d'acides biliaires, comme le demontre la fonction de pheromone exercee par le melange d'acides biliaires pour guider les lamproies marines migratrices vers leurs cours d'eau de fraie. Une comprehension globale des communications chimiques impliquees dans le comportement migrateur des lamproies peut mener a des approches scientifiques ameliorees dans les efforts de restauration. [Traduit par la Redaction], Introduction The Pacific lamprey Lampetra (Entosphenus) tridentata has declined throughout much of its range in the Columbia River basin of North America (Close et al. 2002). Concerns about the declining [...]

Conservation and management of Pacific Lamprey Entosphenus tridentatus and other imperiled lamprey species could include the use of chemosensory cues to attract or repel migrating adults. For restoration programs, using cues to help guide lamprey through fishway entrances might improve passage of adult lamprey at dams. In contrast, odors might repel unwanted invasive Sea Lamprey Petromyzon marinus in the Laurentian Great Lakes from spawning habitats or improve trapping efficiency. We conducted bioassays with Pacific Lamprey in a two-choice maze to evaluate the behavioral response of preovulatory adult females to introduced chemical cues and changes in flow. During overnight tests, for each female we measured the number of entries into each arm of the maze and the amount of time spent in each arm after application of natural odors from prespawning conspecifics (males and females) in one of the arms. Using the same methods, we also tested whether adult females were attracted to natural odor from spermiating males, to a synthesized (artificially produced) component of a Sea Lamprey sex pheromone (3-keto petromyzonol sulfate), or to an attraction flow (12 L/min as reference). In all tests, the lamprey showed consistent nocturnal activity, typically moving from sunset until sunrise and remaining inactive during daylight hours. For natural odors, the number of entries and the amount of time females spent in the treatment arm were not significantly different between control and treatment periods. However, females spent significantly less time in the treatment arm with the synthesized 3-keto petromyzonol sulfate than when we delivered no odor. Females showed strong, positive responses to the attraction flow and with our assay, we could identify significant behavioral responses when the differences between the control and experimental means were greater than 15–20%. The response of lampreys to sex pheromones may be species-specific, with Pacific Lamprey less likely to respond to conspecific odors than Sea Lamprey. [ABSTRACT FROM AUTHOR]