Simulation-based randomized trial of medical emergency cognitive aids.

BACKGROUND: Medical emergencies are complex and stressful, especially for the young and inexperienced. Cognitive aids (CA) have been shown to facilitate management of simulated medical emergencies by experienced teams. In this randomized trial we evaluated guideline adherence and treatment efficacy in simulated medical emergencies managed by residents with and without CA. METHODS: Physicians attending educational courses executed simulated medical emergencies. Teams were randomly assigned to manage emergencies with or without CA. Primary outcome was risk reduction of essential working steps. Secondary outcomes included prior experience in emergency medicine and CA, perceptions of usefulness, clinical relevance, acceptability, and accuracy in CA selection. Participants were grouped as "medical" (internal medicine and neurology) and "perioperative" (anesthesia and surgery) regarding their specialty. The study was designed as a prospective randomized single-blind study that was approved by the ethical committee of the University Duisburg-Essen (19-8966-BO). TRIAL REGISTRATION: DRKS, DRKS00024781. Registered 16 March 2021-Retrospectively registered, http://www.drks.de/DRKS00024781 . RESULTS: Eighty teams participated in 240 simulated medical emergencies. Cognitive aid usage led to 9% absolute and 15% relative risk reduction. Per protocol analysis showed 17% absolute and 28% relative risk reduction. Wrong CA were used in 4%. Cognitive aids were judged as helpful by 94% of the participants. Teams performed significantly better when emergency CA were available (p < 0.05 for successful completion of critical work steps). Stress reduction using CA was more likely in "medical" than in "perioperative" subspecialties (3.7 ± 1.2 vs. 2.9 ± 1.2, p < 0.05). CONCLUSIONS: In a high-fidelity simulation study, CA usage was associated with significant reduction of incorrect working steps in medical emergencies management and was characterized by high acceptance. These findings suggest that CA for medical emergencies may have the potential to improve emergency care.

Tuning the formation of discrete coordination nanostructures.

Novel surface coordination nanostructures based on cyanosexiphenyl molecules are assembled on a gold surface and investigated by scanning tunneling microscopy and density functional theory. Their formation can be tuned by varying the surface temperature during deposition. Diffusing gold adatoms act as coordination centers for the cyano groups present on one end of the nonsymmetrical molecules.

Moving nanostructures: pulse-induced positioning of supramolecular assemblies.

For the development of nanoscale devices, the manipulation of single atoms and molecules by scanning tunneling microscopy is a well-established experimental technique. However, for the construction of larger and higher order structures, it is important to move not only one adsorbate but also several at the same time. Additionally, a major issue in standard manipulation experiments is the strong mechanical interaction of the tip apex and the adsorbate, which can damage the system under investigation. Here, we present a purely electronic excitation method for the controlled movement of a weakly interacting assembly of a few molecules. By applying voltage pulses, this supramolecular nanostructure is moved in a controlled manner without losing its collective integrity. Depending on the polarity and location of the applied voltage, the movement can be driven in predefined directions. Our gentle purely electronic approach for the controlled manipulation of nanostructures opens new ways to construct molecular devices.

STM manipulation of a subphthalocyanine double-wheel molecule on Au(111).

A new class of double-wheel molecules is manipulated on a Au(111) surface by the tip of a scanning tunneling microscope (STM) at low temperature. The double-wheel molecule consists of two subphthalocyanine wheels connected by a central rotation carbon axis. Each of the subphthalocyanine wheels has a nitrogen tag to monitor its intramolecular rolling during an STM manipulation sequence. The position of the tag can be followed by STM, allowing us to distinguish between the different lateral movements of the molecule on the surface when manipulated by the STM tip.

Synthesis and STM imaging of symmetric and dissymmetric ethynyl-bridged dimers of boron-subphthalocyanine bowl-shaped nanowheels.

The future's wheel: A new class of wheels, based on subphthalocyanine fragments, for future incorporation in functional nanovehicles is reported (see figure). The syntheses of a symmetric wheel, a nitrogen-tagged wheel, and their ethynyl-bridged homodimers are presented. Theoretical calculations and STM imaging demonstrate the advantage of a bowl-shaped structure and the efficiency of the tag for STM imaging.

Tiled++: an enhanced tiled hi-res display wall.

In recent years, high-resolution displays have become increasingly important to decision makers and scientists because large screens combined with a high pixel count facilitate content rich, simultaneous display of computer-generated imagery and high-definition video data from multiple sources. Tiled displays are attractive due to their extended screen real estate, scalability, and low cost. LCD panels are usually preferred over projectors because of their superior resolution. One of the drawbacks of LCD-based tiled displays is the fact that users sometimes get distracted by the screens' bezels, which cause discontinuities in rendered images, animations, or videos. Most conventional solutions either ignore the bezels and display all pixels, causing objects to become distorted, or eliminate the pixels that would normally fall under the bezels, causing pixels to be missing in the display of static images. In animations, the missing pixels will eventually reappear when the object moves, providing an experience that is similar to looking through a French window. In this paper, we present a new scalable approach that leads neither to discontinuities nor to significant loss of information. By projecting onto the bezels, we demonstrate that a combination of LCD-based tiled displays and projection significantly reduces the bezel problem. Our technique eliminates ambiguities that commonly occur on tiled displays in the fields of information visualization, visual data analysis, human-computer interaction, and scientific data display. It improves the usability of multimonitor systems by virtually eliminating the bezels. We describe a setup and provide results from an evaluation experiment conducted on a 3 x 3 and on a 10 x 5 tiled display wall.

Visualization of osseointegration of maxilla and mandible dental implants.

PURPOSE: We present a new, hybrid visualization method that can assist in assessing the degree of osseointegration of dental implants. METHOD: The method is based on radiographic imaging, three-dimensional (3-D) volume reconstruction, and color coding of bone density. It provides both a 3-D image of the titanium implant and the implant site, and a two-dimensional (2-D) profile of the lingual and buccal sides of the implant, exposing possible weaknesses in the supporting bone structure. The visualization procedure described here consists of 2-D cross-sectional CT imaging, 3-D gradient-based hardware-accelerated volume rendering using 3-D texture mapping, implant site extraction using 3-D selection of a 2-D cross-sectional, tri-linearly interpolated 2-D image, computation of a bone density profile and line integral along the implant, and 3-D hybrid rendering of the implant site and the derived bone density information in its anatomical context. This method has been demonstrated to be successful in enabling the mapping of information derived from virtual bone density measurements onto a geometric object, thus providing the necessary information to relate other information from mechanical testing or simulations to the respective site. RESULTS: A high-resolution scan of a cadaver was used as a reference data set. The hybrid view, a combination of 2-D density profile and 3-D color-coded density rendering, turned out to be very intuitive and easy to interpret. The 2-D view was also useful for relating standard 2-D X-ray imaging with enhanced 3-D imaging of bone density. On top of this, our image-based method was used for cross-validation of a mechanical testing method. It turned out that the results from mechanical testing of osseointegration were very well correlated with the results from our image-based 2-D and 3-D methods. CONCLUSIONS: Since these two methods work in completely different ways (mechanical vs. radiographic) and the results came out are the same, the results provide evidence that both methods for assessing the degree and location of osseointegration are valid. Further studies using additional scans on living subjects will be conducted to provide additional evidence. Cost-efficient X-ray imaging can be used to replace the simulated implant-aligned 2-D X-ray views that were obtained from a 3-D scan.

[Prehospital noninvasive ventilation in a 102-years old patient]. / Kasuistik interaktiv - Respiratorische Insuffizienz bei 102-Jährigem: Intubation vs. NIV in der Präklinik.

Guidelines for the therapy of cardiogenic pulmonary edema or acute exacerbation of COPD imply the use of noninvasive ventilation (NIV). Clinical studies show a decrease in intubation frequency, mortality and length of stay with inhospital NIV. First prehospital reports show a safe and feasible use of NIV in this setting. We report the case of a 102-year old patient who was successfully treated with preclinical NIV.

A novel method for visualization of entire coronary arterial tree.

The complexity of the coronary circulation especially in the deep layers largely evades experimental investigations. Hence, virtual/computational models depicting structure-function relation of the entire coronary vasculature including the deep layer are imperative. In order to interpret such anatomically based models, fast and efficient visualization algorithms are essential. The complexity of such models, which include vessels from the large proximal coronary arteries and veins down to the capillary level (3 orders of magnitude difference in diameter), is a challenging visualization problem since the resulting geometrical representation consists of millions of vessel segments. In this study, a novel method for rendering the entire porcine coronary arterial tree down to the first segments of capillaries interactively is described which employs geometry reduction and occlusion culling techniques. Due to the tree-shaped nature of the vasculature, these techniques exploit the geometrical topology of the object to achieve a faster rendering speed while still handling the full complexity of the data. We found a significant increase in performance combined with a more accurate, gap-less representation of the vessel segments resulting in a more interactive visualization and analysis tool for the entire coronary arterial tree. The proposed techniques can also be applied to similar data structures, such as neuronal trees, airway structures, bile ducts, and other tree-like structures. The utility and future applications of the proposed algorithms are explored.

Analysis of large-scale brain data for brain-computer interfaces.

We present a systematic technique for extraction of useful information from large-scale neural data in the context of brain-computer interfaces. The technique is based on a direct linear discriminant analysis, recently developed for face recognition problems. We show that this technique is capable of extracting useful information from brain data in a systematic fashion and can serve as a general analytical tool for other types of biomedical data, such as images and collections of images (movies). The performance of the method is tested on intracranial electroencephalographic data recorded from the human brain.