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Compounds containing arylpyrrole-, 1,2,4-triazole- and hydrazone structural frameworks have been widely studied and demonstrated to exhibit a wide range of pharmacological properties. Herein, an exploratory series of new 1,2,4-triazole derivatives designed by amalgamation of arylpyrrole and 1,2,4-triazole structural units via a hydrazone linkage is reported. The synthesised compounds were tested in vitro for their potential activity against Mycobacterium tuberculosis (MTB) H37Rv strain. The most promising compound 13 - the derivative without the benzene ring appended to the pyrrole unit displayed acceptable activity (MIC90 = 3.99 μM) against MTB H37Rv, while other compounds from the series exhibited modest to weak antimycobacterial activity with MIC90 values in the range between 7.0 and125 μM. Furthermore, in silico results, predicated using the SwissADME web tool, show that the prepared compounds display desirable ADME profile with parameters within acceptable range.

The importance of remote collaboration grows in an interconnected world as the reasons to avoid travel increase. The spatial rendering and collaboration capabilities of virtual and augmented reality systems are well suited for tasks such as support or training. Users can take a shared perspective to build a common understanding. Also, users may engage in face-to-face cooperation to support interpersonal communication. However, a shared perspective and face-to-face collaboration are both desirable but naturally exclude each other. We place all users at the same location to provide a shared perspective. To avoid overlapping body parts, the avatars of the other connected users are shifted to the side. A redirected body pose modification corrects the resulting inconsistencies. The implemented system is compared to a baseline of two users standing in the same location and working with overlapping avatars. The results of a user study show that the proposed modifications provide an easy to use, efficient collaboration and yield higher co-presence and the feeling of teamwork. Applying redirection techniques to other users opens up novel ways to increase social presence for local or remote collaboration.

In many fields today, it is necessary that a team has to do operational planning for a precise geographical location. Examples for this are staff work, the preparation of surveillance tasks at major events or state visits and sensor deployment planning for military and civil reconnaissance. For these purposes, Fraunhofer IOSB is developing the Digital Map Table (DigLT). When making important decisions, it is often helpful or even necessary to assess a situation on site. An augmented reality (AR) solution could be useful for this assessment. For the visualization of markers at specific geographical coordinates in augmented reality, a smartphone has to be aware of its position relative to the world. It is using the sensor data of the camera and inertial measurement unit (IMU) for AR while determining its absolute location and direction with the Global Navigation Satellite System (GNSS) and its magnetic compass. To validate the positional accuracy of AR markers, we investigated the current state of the art and existing solutions. A prototype application has been developed and connected to the DigLT. With this application, it is possible to place markers at geographical coordinates that will show up at the correct location in augmented reality at anyplace in the world. Additionally, a function was implemented that lets the user select a point from the environment in augmented reality, whose geographical coordinates are sent to the DigLT. The accuracy and practicality of the placement of markers were examined using geodetic reference points. As a result, we can conclude that it is possible to mark larger objects like a car or a house, but the accuracy mainly depends on the internal compass, which causes a rotational error that increases with the distance to the target.

Technological advances enable the development of new low vision aids. One such new technology is virtual reality (VR). Existing VR applications offer a variety of adjustments to the content and the user's environment to support people with low vision. Yet, an interaction concept to conveniently activate and control these aids is missing. Therefore, we designed and implemented an interaction concept based on user and expert feedback and evaluated it in a user study. Our application offers various aids to support residual vision and a radial menu for intuitive use of these aids. The results of the user study show that the VR application allows simple task solving comparable to a desktop computer. Furthermore, the user study gives an insight into the effects of different visual impairments on the usage of VR, since the field of view has a larger impact than visual acuity. Overall, our results indicate that VR is a suitable aid to support the individual needs of users with low vision.

A fast and reliable decision is based on the availability of a precise data basis and expert knowledge. In order to address these aspects for resource planning, we provide an intuitive situation analysis in mixed reality with a seamless transition between conventional location planning and virtual inspection of the operational environment, which in addition to a better understanding of the terrain allows for location-independent cooperation of several users. The basic idea of the presented concept comprises the intuitive application preparation in mixed reality in a realistic 3D environment combined with an efficient 2D situation overview using e.g. a large display, tablet or smartphone. The aim is to enable transparent collaboration between different system environments regardless of the location of the respective users. The aim of the idea is an improved understanding of the terrain and increased situational awareness for fast and demand-oriented location planning. The solution is based on the three building blocks. First, a user-oriented display of high-resolution 3D geodata for a better understanding of the terrain on the basis of data standards, including necessary performance optimizations for use in mixed reality environments. Second, the combination of two-dimensional and three-dimensional display of operational pictures, which allows a choice of means through the synchronization of the information between the different platforms and thus a demand-oriented deployment planning. And third, the support of content-related cooperation of remote users for fast decision making via wired or mobile networks.

Virtual environments (VE) provide immersive experiences that allow users to perceive and interact with three dimensional (3D) content. Yet, the 3D applications are often tailored for specific tasks and hardware setups such as a virtual or augmented reality (VR/AR) head mounted display (HMD). This limits the range of available content, because not every standard application (e.g. web browser, calender, office) that is available on a 2D desktop PC can be easily accessed using VR or AR. As commonly used by other systems, we capture arbitrary 2D windows from a desktop PC and display them as a 2D surface in the VE. Furthermore, we provide different techniques that aim to allow easy and fast interaction with the 2D applications in VR. For example, the work bench tool allows to copy and paste subsections of a 2D window. The copied sections are fully interactable and can be moved around and scaled to provide easy access to small menus. With the macro tool, users can create shortcuts to frequently used functions that are executed by cursor presses or hotkeys. The provided tools yield new ways of interacting with 2D interfaces. By allowing the user to easily interact with already available 2D applications, the productivity of VEs increases strongly.

Immersive output and natural input are two core aspects of a virtual reality experience. Current systems are frequently operated by a controller or gesture-based approach. However, these techniques are either very accurate but require an effort to learn, or very natural but miss haptic feedback for optimal precision. We transfer ubiquitous touch interaction with haptic feedback into a virtual environment. To validate the performance of our im- plementation, we performed a user study with 28 participants. As the results show, the movable and cheap real world object supplies an accurate touch detection that is equal to a laserpointer-based interaction with a controller. Moreover, the virtual tablet can extend the functionality of a real world tablet. Additional information can be displayed in mid-air around the touchable area and the tablet can be turned over to interact with both sides. Therefore, touch interaction in virtual environments allows easy to learn and precise system interaction and can even augment the established touch metaphor with new paradigms.

Mixed reality (MR) devices offer advantages for a wide range of applications, e.g. simulation, communication or training purposes. Local multi user applications allow users to engage with virtual worlds collaboratively, while being in the same physical room. A shared coordinate system is necessary for this local collaboration. However, current mixed reality platforms do not offer a standardized way to calibrate multiple devices. Not all systems offer the required hardware that is used by available algorithms, either because the hardware is not available or not accessible by developers. We propose an algorithm that calibrates two devices using only their tracking data. More devices can be calibrated through repetition. Two MR devices are held together and moved around the room. Our trajectory-based algorithm provides reliable and precise results when compared to SfM or marker based algorithms. The accurate, but easy to use rotational calibration gesture can be executed effortlessly in a small space. The proposed method enables local multi user collaboration for all six degrees of freedom (DOF) MR devices.

In the present study, we evaluated the phytochemical compounds and antioxidant properties of chloroform, ethanol and acetone extracts for leaves and flowers of Leonutus leonurus (L. leonurus) alongside with their cytotoxic effects on human cervical carcinoma (HeLa) cell lines. The phytochemical compounds present in the leaves and flowers of L. leonurus included; phenolics, flavonoids and alkaloids. Their radicals scavenging effects against 2, 2-diphenyl-1-picrylhydrazyl [DPPH] 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) [ABTS·+], hydrogen peroxide, nitric oxide as well as metal chelating activities showed dose-dependent activities. Gas chromatography-mass spectrometry (GCMS) analyses revealed the presence of important bioactive compounds, which are associated with antioxidant; and the extracts exhibited toxicity effect against HeLa cells. The findings from this study divulge extracts of L. leonurus as prospective sources of antioxidant and anticancer agents; and hence, further study on their neuroprotective potentials becomes imperative.

Immersive output and effortless input are two core aspects of a virtual reality (VR) experience. We transfer ubiquitous touch interaction with haptic feedback into a virtual environment (VE). The movable and cheap real world object supplies an accurate touch detection equal to a ray-casting interaction with a controller. Moreover, the virtual tablet extends the functionality of a real world tablet. Additional information is displayed in mid-air around the touchable area and the tablet can be turned over to interact with both sides. It allows easy to learn and precise system interaction and can even augment the established touch metaphor with new paradigms.

Virtual Reality opens up new possibilities as it allows to overcome real-life limitations and create novel experiences. While interacting with other people, it is beneficial to share a common view point. We modify the virtual world to allow face-to-face interaction with another person, while still retaining an optimal point of view on presented data. This is done by adapting the virtual environment independently for each user, using translation, rotation and scaling. The presented modification of the world gives a natural solution to the problems of collaborative analysis of content. It is therefore beneficial for usage in human-human interaction scenarios that support cooperative work.

Virtual Reality applications transfer users into immersive virtual environments, which can be shared with other remote or local users. Yet, multiple local users may collide, since the HMD obscures the view on the other party. To overcome this issue, a user avatar allows to estimate the location of others and to avoid collisions. However, different avatar representations can be used. We compare four avatars in a 28 participant user study. The comparison shows that the different avatars affect the number of collisions and the overall feeling of safety. As a result, local VR collaboration applications should represent the body of the user or highlight his or her location to increase user safety.

With increasing task and system complexity, it becomes necessary to support workers, e.g. performing repair tasks, from a remote location. Current approaches utilize images or a video stream combined with annotations and speech to allow collaboration with remote users. We propose a technique that gives the remote supporter the ability to see a high fidelity point cloud of a real world object in Virtual Reality (VR). The VR user can indicate points of interest via a laser pointer. The local worker sees these indications on top of the real object with an Augmented Reality (AR) headset. A preliminary user study shows that the proposed method is faster and less error-prone regarding the comprehension of the object and the communication between the users. In addition to that, the system has a higher usability. This work shows that even non-virtual, collaborative tasks can be supported by new forms of user interaction using different technologies like VR and AR.

Virtual Reality enables a new form of collaboration. It allows users to work together in the same virtual room regardless of their actual physical location. However, it is unclear which effect the physical location of the user has on task performance, the feeling of presence or immersion. We compared the collaboration of two users in the same local room and in remote rooms on the basis of a knowledge-transfer task. An instructor indicated different virtual objects using three different pointing gestures and a trainee selected the highlighted object. The results of a 28 participant user study show that the performance of the gestures in the local and remote setup is equal, according to NASA-TLX, rankings and time. Users feel equally co-present and tend to prefer the remote collaboration. The data presented in this paper shows that VR collaboration in a virtual room is independent from the physical location of the participants. This allows the development of VR applications without special consideration of the user’s location. VR systems can use the advantages of a remote collaboration, like faster reaction times, no travel expenses and no user collision, or of local collaboration, e.g. direct contact between users.

Virtual Reality systems offer great possibilities to analyze and interact with data. However, they still lack a commonly accepted, efficient text input technique that allows users to record their findings. To provide users with an efficient technique for text input, a real keyboard and the user’s hands are transferred into the virtual world. This allows real haptic feedback of the device and, as a user study shows, results in fast and accurate text writing. The proposed approach shows that a real-world ability can be transmitted directly into the virtual world without much loss.

With the emerging technologies of Virtual and Augmented Reality (VR/AR) and the increasing performance of mobile and desktop devices the amount of 3D-based applications rapidly increases. This 3D content demands for an efficient and well suited 3D interaction. Currently there are many manipulation techniques for different input and output devices, like mouse, touchscreen, gestures, 2D-based monitors or 3D-based head mounted displays (HMDs), but there is no general overview covering all interaction techniques. This paper delivers an extensive overview of different approaches and classifies these according to input device, functionality (translation, rotation, scaling, with discrete mode or modeless interaction, uni- or bi-manual). If available, evaluation results or comparisons to other techniques are presented. Each technique is then rated under the aspects of speed, beginner-friendliness and mental and physical demand.

Mitochondria are key to eukaryotic cell survival and their activity is linked to generation of reactive oxygen species (ROS) which in turn acts as both an intracellular signal and an effective executioner of cells with regards to cellular senescence. The mitochondrial molecular chaperone tumor necrosis factor receptor associated protein 1 (TRAP1) is often termed the cytoprotective chaperone for its role in cancer cell survival and protection from apoptosis. Here, we hypothesize that TRAP1 serves to modulate mitochondrial activity in stem cell maintenance, survival and differentiation.

Grid service companies in today’s liberalized electrical energy markets face the key challenge to balance cost efficiency and quality of supply under increasingly complex conditions. Therefore questions concerning process analysis and process improvement are getting more and more into focus since some years. This paper presents a full control centre operation model for High-/Medium-/Low-Voltage-grids (HV-/MV-/LV-grids) in combination with a grid operation model. The new model allows to optimise the number of control centres including the number of control stations with regard to the amount of planned (maintenance) and un-planned (incidents, outages) work in the grid.