Koc University 4 articles published in JoVE Developmental Biology Left Atrial Ligation in the Avian Embryo as a Model for Altered Hemodynamic Loading During Early Vascular Development Bortecine Sevgin*1, Merve Nur Coban*1, Faruk Karatas2, Kerem Pekkan1,2 1Department of Biomedical Sciences and Engineering, Koc University, 2Department of Mechanical Engineering, Koc University Here, we present a detailed visual protocol for executing the left atrial ligation (LAL) model in the avian embryo. The LAL model alters the intracardiac flow, which changes wall shear stress loading, mimicking hypoplastic left heart syndrome. An approach to overcome the challenges of this difficult microsurgery model is presented. Biology Culturing, Freezing, Processing, and Imaging of Entire Organoids and Spheroids While Still in a Hydrogel Olgu Enis Tok1,2, Gamze Demirel2,3, Yusuf Saatci1, Zeynep Akbulut3,5, Ozgecan Kayalar6, Ranan Gulhan Aktas2,3,4 1Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, 2Cellorama, 3Cancer and Stem Cell Research Center, Maltepe University, 4Department of Histology and Embryology, School of Medicine, Maltepe University, 5Department of Medical Biology, School of Medicine, Maltepe University, 6School of Medicine, Koc University The present study describes methodologies for culturing, freezing, thawing, processing, staining, labeling, and examining entire spheroids and organoids under various microscopes, while they remain intact in a hydrogel within a multipurpose device. Developmental Biology Transuterine Fetal Tracheal Occlusion Model in Mice Emrah Aydın1,2, Rashika Joshi3, Marc Oria1, Foong-Yen Lim1, Brian Michael Varisco3, Jose Luis Peiro1 1The Division of Critical Care Medicine, Department of Pediatrics, Cincinnati Children’s Hospital Medical Center Various animal models of congenital diaphragmatic hernia and fetal tracheal occlusion present advantages and disadvantages regarding ethical issues, cost, surgical difficulty, size, survival rates, and availability of genetic tools. This model provides a new tool to study the impact of both tracheal occlusion and increased luminal pressure on lung development. Behavior Automated, Quantitative Cognitive/Behavioral Screening of Mice: For Genetics, Pharmacology, Animal Cognition and Undergraduate Instruction C. R. Gallistel1, Fuat Balci1,2, David Freestone1,3, Aaron Kheifets1, Adam King4 1Department of Psychology, Rutgers University, 2Department of Psychology, Koç University, 3Center for Neural Science, New York University, 4Department of Mathematics & Computer Science, Fairfield University Fully automated system for measuring physiologically meaningful properties of the mechanisms mediating spatial localization, temporal localization, duration, rate and probability estimation, risk assessment, impulsivity, and the accuracy and precision of memory, in order to assess the effects of genetic and pharmacological manipulations on foundational mechanisms of cognition in mice.