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Objective To collect real-world data to demonstrate the safety and performance of Arrowg+ard Blue® /Arrowg+ard Blue Plus® (AGB/AGB+) central venous catheters (CVCs). Methods This observational, retrospective study involved patients who required AGB/AGB+ CVCs at designated general hospitals in USA (22), UK (19) and Germany (2). Data were extracted from electronic medical records. There were no specific inclusion/exclusion criteria. Primary endpoint was successful treatment without an adverse event (AE). Secondary endpoint was rate of AEs. Results In total, 384 cases were included from 43 centres and most patients (74%) were >35 years of age. A success rate of 99%, and an overall AE rate of 0.8% were observed. Moreover, the overall infection rate was lower than typically reported for standard catheters. In addition, power injection of contrast media was successful in all 51 cases. Conclusions This study indicates the AGB/AGB+ CVCs perform as intended with a high success rate and few AEs. Further large-scale, controlled studies are required to confirm our findings.

The creation of personalized avatars that may be morphed to simulate realistic changes in body size is useful when studying self-perception of body size. One drawback is that these methods are resource intensive compared to rating scales that rely upon generalized drawings. Little is known about how body perception ratings compare across different methods, particularly across differing levels of personalized detail in visualizations. This knowledge is essential to inform future decisions about the appropriate tradeoff between personalized realism and resource availability. The current study aimed to determine the impact of varying degrees of personalized realism on self-perception of body size. We explored this topic in young adult women, using a generalized line drawing scale, as well as several types of personalized avatars, including 3D textured images presented in immersive virtual reality (VR). Body perception ratings using generalized line drawings were often higher than responses using individualized visualization methods. While the personalized details seemed to help with identification, there were few differences among the three conditions containing different amounts of individualized realism (e.g., photo-realistic texture). These results suggest that using scales based on personalized texture and limb dimensions are beneficial, although presentation in immersive VR may not be essential.

Past work has suggested that perception of object distances in natural scenes depends on the environmental surroundings, even when the physical object distance remains constant. The cue bases for such effects remain unclear and are difficult to study systematically in real-world settings, given the challenges in manipulating large environmental features reliably and efficiently. Here, we used rendered scenes and crowdsourced data collection to address these challenges. In 4 experiments involving 452 participants, we investigated the effect of room width and depth on egocentric distance judgments. Targets were placed at distances of 2-37 meters in rendered rooms that varied in width (1.5-40 meters) and depth (6-40 meters). We found large and reliable effects of room width: Average judgments for the farthest targets in a 40-meter-wide room were between 16-33% larger than for the same target distances seen in a 1.5-meter-wide hallway. Egocentric distance cues and focal length were constant across room widths, highlighting the role of environmental context in judging distances in natural scenes. Obscuring the fine-grained ground texture, per se, is not primarily responsible for the width effect, nor does linear perspective play a strong role. However, distance judgments tended to decrease when doors and/or walls obscured more distant regions of the scene. We discuss how environmental features may be used to calibrate relative distance cues for egocentric distance judgments.

When navigating by path integration, knowledge of one's position becomes increasingly uncertain as one walks from a known location. This uncertainty decreases if one perceives a known landmark location nearby. We hypothesized that remembering landmarks might serve a similar purpose for path integration as directly perceiving them. If this is true, walking near a remembered landmark location should enhance response consistency in path integration tasks. To test this, we asked participants to view a target and then attempt to walk to it without vision. Some participants saw the target plus a landmark during the preview. Compared with no-landmark trials, response consistency nearly doubled when participants passed near the remembered landmark location. Similar results were obtained when participants could audibly perceive the landmark while walking. A control experiment ruled out perceptual context effects during the preview. We conclude that remembered landmarks can enhance path integration even though they are not directly perceived. (Contains 4 tables, 2 figures and 1 footnote.)

In order to gain insight into the nature of human spatial representations, the current study examined how those representations are affected by blind rotation. Evidence was sought on the possibility that whereas certain environmental aspects may be updated independently of one another, other aspects may be grouped (or chunked) together and updated as a unit. Participants learned the locations of an array of objects around them in a room, then were blindfolded and underwent a succession of passive, whole-body rotations. After each rotation, participants pointed to remembered target locations. Targets were located more precisely relative to each other if they were (a) separated by smaller angular distances, (b) contained within the same regularly configured arrangement, or (c) corresponded to parts of a common object. A hypothesis is presented describing the roles played by egocentric and allocentric information within the spatial updating system. Results are interpreted in terms of an existing neural systems model, elaborating the model's conceptualization of how parietal (egocentric) and medial temporal (allocentric) representations interact. (Contains 7 figures, 3 tables and 6 footnotes.)

D. R. Proffitt and colleagues (e. g., D. R. Proffitt, J. Stefanucci, T. Banton, & W. Epstein, 2003) have suggested that objects appear farther away if more effort is required to act upon them (e.g., by having to throw a ball). The authors attempted to replicate several findings supporting this view but found no effort-related effects in a variety of conditions differing in environment, type of effort, and intention to act. Although they did find an effect of effort on verbal reports when participants were instructed to take into account nonvisual (cognitive) factors, no effort-related effect was found under apparent- and objective-distance instruction types. The authors' interpretation is that in the paradigms tested, effort manipulations are prone to influencing response calibration because they encourage participants to take nonperceptual connotations of distance into account while leaving perceived distance itself unaffected. This in no way rules out the possibility that effort influences perception in other contexts, but it does focus attention on the role of response calibration in any verbal distance estimation task. (Contains 3 tables, 4 figures and 1 footnote.)

Human spatial representations of object locations in a room-sized environment were probed for evidence that the object locations were encoded relative not just to the observer (egocentrically) but also to each other (allocentrically). Participants learned the locations of 4 objects and then were blindfolded and either (a) underwent a succession of 70[degree] and 200[degree] whole-body rotations or (b) were fully disoriented and then underwent a similar sequence of 70[degree] and 200[degree] rotations. After each rotation, participants pointed to the objects without vision. Analyses of the pointing errors suggest that as participants lost orientation, represented object directions generally "drifted" off of their true directions as an ensemble, not in random, unrelated directions. This is interpreted as evidence that object-to-object (allocentric) relationships play a large part in the human spatial updating system. However, there was also some evidence that represented object directions occasionally drifted off of their true directions independently of one another, suggesting a lack of allocentric influence. Implications regarding the interplay of egocentric and allocentric information are considered. (Contains 5 footnotes, 6 figures, and 2 tables.)

When navigating by path integration, knowledge of ones position becomes increasingly uncertain as one walks from a known location. This uncertainty decreases if one perceives a known landmark location nearby. We hypothesized that remembering landmarks might serve a similar purpose for path integration as directly perceiving them. If this is true, walking near a remembered landmark location should enhance response consistency in path integration tasks. To test this, we asked participants to view a target and then attempt to walk to it without vision. Some participants saw the target plus a landmark during the preview. Compared with no-landmark trials, response consistency nearly doubled when participants passed near the remembered landmark location. Similar results were obtained when participants could audibly perceive the landmark while walking. A control experiment ruled out perceptual context effects during the preview. We conclude that remembered landmarks can enhance path integration even though they are not directly perceived.

Path integration is a process in which observers derive their location by integrating self-motion signals along their locomotion trajectory. Although the medial temporal lobe (MTL) is thought to take part in path integration, the scope of its role for path integration remains unclear. To address this issue, we administered a variety of tasks involving path integration and other related processes to a group of neurosurgical patients whose MTL was unilaterally resected as therapy for epilepsy. These patients were unimpaired relative to neurologically intact controls in many tasks that required integration of various kinds of sensory self-motion information. However, the same patients (especially those who had lesions in the right hemisphere) walked farther than the controls when attempting to walk without vision to a previewed target. Importantly, this task was unique in our test battery in that it allowed participants to form a mental representation of the target location and anticipate their upcoming walking trajectory before they began moving. Thus, these results put forth a new idea that the role of MTL structures for human path integration may stem from their participation in predicting the consequences of one's locomotor actions. The strengths of this new theoretical viewpoint are discussed.

Classroom Web sites have the potential to support and enhance student learning by targeting 21st century skills, such as collaboration among teachers, students, parents, and other teachers, media literacy, and interpersonal and self-directional skills, as well as thinking and problem-solving skills. Web 2.0 tools such as blogs, vokis, and podcasts enhance teacher Web sites to prepare students for the future. By making learning a social event, teachers help to keep students engaged with course material. In addition, teachers are supporting 21st century skills through the posting of student work so that classmates may comment on and refine one another's products. In this paper, the authors report on their study of classroom Web sites to determine whether they specifically support 21st century skills. Preliminary findings suggest that classroom Web sites are not meeting the needs of the 21st century student. Additional findings highlight that most classroom teachers are self-taught in terms of Web-site development. Based on their findings, the authors developed recommendations for educators who want to produce a classroom Web site aligned with the standards for learning in the 21st century. (Contains 1 table and 16 online resources.)