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There have been significant changes in undergraduate civil engineering curricula in the last two decades. Key issues for university curriculum committees are selection and transference of appropriate skills and attributes for students to succeed in the industry. Despite significant changes occurring in teaching theories, civil engineering education still relies heavily on deductive instruction. Case-based teaching is one of the most widespread forms of inductive learning and this paper describes the differences between two of the most familiar types: 'case- histories' and 'case-studies'. These methods are presented using the Kansas City Hyatt Regency walkway collapse as an exemplar. The benefits of using this approach are improved retention of knowledge, better reasoning and analytical skills, development of higher-order skills, greater ability to identify relevant issues and recognize multiple perspectives, higher motivation and awareness of non-technical issues. Many of these outcomes are part of the expected attributes of civil engineers outlined by professional bodies. Key words: civil engineering, education, pedagogy, inductive teaching, case- study, case-history, constructivism, failure, problem-solving, structures. Les programmes d'enseignement de premier cycle en genie civil ont subi de grands changements au cours des deux dernieres decennies. Les questions cles pour les comites de programmes universitaires sont la selection et le transfert des connaissances et des qualites appropriees aux etudiants pour qu'ils reussissent dans l'industrie. Malgre des changements importants dans les theories d'enseignement, l'education en genie civil est encore grandement fondee sur l'apprentissage deductif. L' enseignement base sur des cas est l' une des formes les plus etendues de l' apprentissage inductif et le present article decrit les differences entre les deux types les plus familiers : l' etude des dossiers individuels et la methode des cas. Ces methodes sont presentees en utilisant l'exemple de l'effondrement de la passerelle du Hyatt Regency de Kansas City. Les avantages d' utiliser cette approche sont une retention amelioree des connaissances, de meilleures capacites analytiques et de raisonnement, le developpement de capacites d'ordre superieur, une meilleure capacite a identifier les questions pertinentes et a reconnaitre les multiples points de vue, une meilleure motivation et une sensibilisation aux questions non techniques. Plusieurs de ces resultats font partie des qualites escomptees chez les ingenieurs civils, tels que soulignees par les corps professionnels. genie civil, education, pedagogie, enseignement inductif, methode des cas, etude de dossiers individuels, constructivisme, defaillance, resolution de problemes, structures. [Traduit par la Redaction], 1. Introduction Over the last 20 years there have been significant changes in undergraduate civil engineering curricula in response to student, industry and societal needs, accrediting professional bodies and government [...]

Purpose: To identify anomalous features that impact drug delivery in the eye as a result of intravitreal injections using micro-computed tomography imaging. Methods: Three-dimensional micro-computed tomography images were acquired following an intravitreal injection of 0.03 mL of contrast agent into ex vivo porcine eyes ( n = 24). A baseline scan was acquired prior to injection to detect any abnormalities in the eyes. Acquisition continued at various time intervals up to 230 min post-injection. Results: Air bubbles were clearly visible within the vitreous of 21 eyes following injections. There was a total of 36 air bubbles in the 21 eyes and the volume of the air bubbles ranged from 0.01 µL to 1.50 µL. It was found the size of the air bubbles decreased over the scanning period. Furthermore, many of the injected boli in the eye specimens did not have the commonly assumed spherical shape; rather, a variety of other shapes resulted. Conclusion: The presence of air bubbles and inconsistent bolus shapes have indicated that intravitreal injections have high variability. It is only through the realization of these anomalous features that the efficacy of intravitreal drug delivery will be improved through a consistent and accurate injection technique. [ABSTRACT FROM AUTHOR]

Research Highlights: Simulations of treefall patterns during tornado events have been conducted, enabling the coupled effects of tornado characteristics, tree properties and soil conditions to be assessed for the first time. Background and Objectives: Treefall patterns and forest damage assessed in post-storm surveys are dependent on the interaction between topography, biology and meteorology, which makes identification of characteristic behavior challenging. Much of our knowledge of tree damage during extreme winds is based on synoptic storms. Better characterization of tree damage will provide more knowledge of tornado impacts on forests, as well as their ecological significance. Materials and Methods: a numerical method based on a Rankine vortex model coupled with two mechanistic tree models for critical wind velocity for stem break and windthrow was used to simulate tornadic tree damage. To calibrate the models, a treefall analysis of the Alonsa tornado was used. Parametric study was conducted to assess induced tornadic tree failure patterns for uprooting on saturated and unsaturated soils and stem break with different knot factors. Results: A power law relationship between failure bending moments and diameter at breast height (DBH) for the hardwood species provided the best correlation. Observed failure distributions of stem break and windthrow along the tornado track were fitted to lognormal distributions and the mean of the critical wind speeds for windthrow were found to be higher than that for stem break. Relationships between critical wind speed and tree size were negatively correlated for windthrow and positively correlated for stem break. Higher soil moisture contents and lower knot factors reduced the critical wind speeds. The simulations show varying tree fall patterns displaying forward and backward convergence, different tornado damage widths and asymmetry of the tracks. These variations were controlled by the relative magnitudes of radial and tangential tornado velocities, the ratio between translational speed and maximum rotational wind speed and the mode of failure of the trees. Conclusions: The results show the complexity of predicting tornadic damage in forests, and it is anticipated that this type of simulation will aid risk assessments for insurance companies, emergency managers and forest authorities. [ABSTRACT FROM AUTHOR]