As an important technique for data pre-processing, outlier detection plays a crucial role in various real applications and has gained substantial attention, especially in medical fields. Despite the importance of outlier detection, many existing methods are vulnerable to the distribution of outliers and require prior knowledge, such as the outlier proportion. To address this problem to some extent, this article proposes an adaptive mini-minimum spanning tree-based outlier detection (MMOD) method, which utilizes a novel distance measure by scaling the Euclidean distance. For datasets containing different densities and taking on different shapes, our method can identify outliers without prior knowledge of outlier percentages. The results on both real-world medical data corpora and intuitive synthetic datasets demonstrate the effectiveness of the proposed method compared to state-of-the-art methods.

In the early stages of 3D design, sketches are used to quickly conceptualize ideas and gain insight into problems and possible solutions. Computer-aided design tools are widely used for 3D modeling and design, but their required precision and 2D mouse and screen-based interface inhibit the flow of ideas. A study was conducted to explore the efficiency of hand tracking and virtual reality (VR) for 3D object manipulations in conceptual design. Based on existing research on conceptual design and hand gestures, an intuitive hand-based interaction model is proposed. An experiment on basic 3D manipulation shows that participants using a simple VR and hand-tracking interface prototype have similar performance to those using a traditional mouse and screen interface. For the improvement of gestural conceptual design interfaces, the relevant issues are identified.

Magnetic resonance microscopy (MRM) is an imaging modality that allows for noninvasive acquisition of high-resolution images in intact opaque animals. The zebrafish (Danio rerio) is an important model organism for the study of vertebrate biology. However, optical in vivo studies in zebrafish are restricted to very early developmental stages due to the opacity of the juvenile and adult stages. Application of high resolution MRM has not yet been explored in adult zebrafish. In this study we applied and optimized high resolution MRM methods to examine anatomical structures noninvasively in adult zebrafish. Clear morphological proton images were obtained by T(2)-weighted spin echo and rapid acquisition with rapid acquisition with relaxation enhancement (RARE) sequences which revealed many anatomical details in the entire intact zebrafish at a magnetic field strength of 9.4 T. In addition, in vivo imaging of adult zebrafish revealed sufficient anatomical details. To our knowledge this is the first report of the application of high resolution MRM to study detailed anatomical structures in adult zebrafish.

There is no agreement, in the chick, about the number of the endocardial cushions within the outflow tract or their pattern of fusion. Also, little is known of their relative contributions to the formation of the arterial valves, the subpulmonary infundibulum, and the arterial valvar sinuses. As the chick heart is an important model for studying septation of the outflow tract, our objective was to clarify these issues. Normal septation of the outflow tract was studied in a series of 60 staged chick hearts, by using stained whole‐mount preparations, serial sections, and scanning electron microscopy. A further six hearts were examined subsequent to hatching. At stage 21, two pairs of endocardial cushions were seen within the developing outflow tract. One pair was positioned proximally, with the other pair located distally. By stage 25, a third distal cushion had developed. This finding was before the appearance of two further, intercalated, endocardial cushions, also distally positioned, which were first seen at stage 29. In the arterial segment, the aortic and pulmonary channels were separated by the structure known as the aortopulmonary septum. The dorsal limb of this septum penetrated the distal dorsal cushion, whereas the ventral limb grew between the remaining two distal cushions, both of which were positioned ventrally. The three distal endocardial cushions, and the two intercalated endocardial cushions, contributed to the formation of the leaflets and sinuses of the arterial roots. The two proximal cushions gave rise to a transient septum, which later became transformed into the muscular component of the subpulmonary infundibulum. Concomitant with these changes, an extracardiac tissue plane was formed which separated this newly formed structure from the sinuses of the aortic root. Our study confirms that three endocardial cushions are positioned distally, and two proximally, within the developing outflow tract of the chick. The pattern of the distal cushions, and the position of the ventral limb of the aortopulmonary septum, differs significantly from that seen in mammals. Anat Rec 264:273–283, 2001.