bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Design of an Avatar in a Multiplayer Serious Game
Authors: Jakob Rebekka , Schmücker Vanessa , Joan Eiler Tanja , Grensing Florian , Brück Rainer 
Published: September 2022

Abstract
Avatars are often used to represent people in the virtual world. In the process, they can also have numerous psychological influences on the users. Therefore, this paper discusses a multiplayer application in virtual reality and how a appealing avatar could be designed in it. In a small study with six persons the application was tested competitively in teams of two, the users filled out a questionnaire and answered some additional questions. While an increase in motivation was observed in all participants, the choice of the preferred avatar was not uniform. Thus, this showed that an appealing avatar for everyone could not simply be determined, but personal preferences and experience must be taken into account.
Topology-optimized patient-specific osteosynthesis plates
Authors: Maintz Michaela , Seiler Daniel , Thieringer Florian M. , Wild Michael de 
Published: September 2022

Abstract
Patient-specific osteosynthesis plates can be used to reduce complications related to bone fracture treatment, such as infection, malocclusion and fatigue fractures of plates and screws. However, the implant design process is tedious. We propose a semi-automatic workflow to computationally design patient-specific titanium osteosynthesis plates for mandibular angle fractures. In this process, the plate stiffness is maximized while the mass is reduced. Two plate designs with different numbers of screw holes (implant #1 with four holes, implant #2 with eight holes) were generated with identical topology optimization settings and compared in a finite element model simulating various biomechanical masticatory loads. Differences in von Mises stresses in the implants and screws were observed. The load case of clenching the jaw on the opposite side of the fracture showed the highest stress distribution in implant #1 and higher peak stresses in implant #2. Stress concentrations were observed in sharp corners of the implant and could be reduced using local stress-based topology optimization. We conclude that the design process is an effective method to generate patientspecific implants.
Preliminary validation system for cuffless blood pressure measurement
Authors: Gonçalves Seabra Ana Carolina , Ferreira da Silva Alexandre , Stieglitz Thomas , Belen Amado-Rey Ana 
Published: September 2022

Abstract
The development of a non-invasive, cuffless, continuous, wearable device for the measurement of blood pressure is a complex endeavour due to the high specificity at each measuring site and the need for high accuracy. Proof-ofconcept and validation of a prototype should be performed at an early stage for functionality assessment. Additionally, the emergence of biological computer models allows for in-silico research, which results should be verified in a practical experiment. To grant an optimal preliminary assessment of a prototype, this work aimed to develop and validate accurate in-vitro and ex-vivo arterial models, with simple construction and easily available components. The comparison between a silicone tube and a porcine artery as a mimicked human radial artery was based on the stiffness parameter. Flow pressure is controlled by a centrifugal heart-like pump. Pressure values are extracted with ultrasound and a commercial piezoresistive pressure sensor is used for pressure validation. The porcine artery showed much more realistic stiffness values (·=15.360) than the silicon tube (·=543.420), which was very stiff in comparison to the typical in-vivo radial artery stiffness (·=9.5). The decrease in stiffness of 97.173 % (from the silicone tube to the porcine artery) led to an acute decrease in the derived pressure error. This work serves as guidelines for the development of a low-budget arm phantom, as the simple setup allowed for a primary validation of a proof-of-concept ultrasound-based sensor for the measurement of pressure.
Cross-spectral analysis quantifies the segmental coordination in unstable sitting
Authors: Roberts Brad , Vette Albert 
Published: September 2022

Abstract
Introduction: Low back pain(LBP) affects many individuals and is known to be associated with impaired trunk control. While LBP can be associated by treating underlying trunk impairments, a better understandinf of the mechanistic origin of the disorder is required. Trunk control has been commonly studied via an unstable sitting paradigm. Knowledge on how the base of support and body segments work together to complete the unstable sitting task, and how this is modified in individuals with LBP, could be utilized when designing interventions for this population. Our obiective was to characterize the segmental coordination in non-impaired unstable sitting as elicited via a wobble board(WB) paradigm. Methods: WB, pelvis, and trunk motion were recorded in fifteen non-disabled participants sitting on a wobble board. We used cross-spectral analysis to quantify the coordination of the anterior-posterior angular kinematics of the wobble board, pelvis, and trunk. Results: During unstable sitting, the motion of the pelvis was followed by that of the trunk(one-eighth-cycle delay) and wobble board(half-cyclw delay) at frequenties between 1 and 2 Hz. Conclusion: Future work should utilize the knowledge gained in this study when creating rehabilitation interventions for individuals with LBP.
Clinical utility of gait stability measures: Selection and preliminary evaluation of the margin of stability
Authors: Hall Jeremy C. , Roberts Brad W.R. , Bahari Hosein , Forero Juan , Rouhani Hossein , Hebert Jacqueline S. , Vette Albert H. 
Published: September 2022

Abstract
Introduction: gait-related falls account for most falls in the elderly. The identification of individuals at risk of falling due to unstable gait requires clinically feasible measures that can detect impairments in gait. Our obiective was to : (1) assess the feasibility for clinical implementation of existing gait stability measures and selected measures to detect gait impairments. Methods: Nine measures were assessed for clinical feasibility, with only the margin of stability(MOS) being selected for evaluation. Ground reactions and motion of the lower body were recorded in fifteen non-disabled and three disabled participants during treadmil walking. Media-lateral MOS was calculated and compared between the non-disabled and disabled participants to evaluate its ability to detect gait impairments. Results: MOS values at heel strike(HS) and at the point between HS and contralateral toe-off with minimum MOS deviated between participants with lower limb impaiments and non-disabled participants. Conclusion: MOS at HS demonstrated the greatest potential to assess fall risk. Additional work is required before MOS can be recommanded for clinical use.
Development of a Venous Collapse Prevention Device for Blood Draw
Authors: Liu Jan , Heumann Maximilian , Stewart Kent W. , Pott Peter P. 
Published: September 2022

Abstract
Blood sampling typically involves puncturing a superficial vein with a needle and then creating a vacuum (e. g., with a syringe) to transfer the blood from the venous system to the collection container. In some cases, the venous walls collapse due to excessive vacuum generated. In this work, a device is presented that prevents venous collapse and can be combined with any blood collection system available on the market. The mechanism of preventing venous collapse is based on a tubular segment interconnected between the needle and the syringe, which collapses at a lower vacuum pressure than the vein. The prototype was tested and evaluated using a test rig that simulates venous blood draw. The experiments proved the functionality of the device on a vein phantom.
Development of a compact sterilization and shredding machine for infectious or toxic wastes (MACS 800)
Authors: Taraschuk Igor , Reuter Thomas , Luft Conrad , Modaleck Toni 
Published: September 2022

Abstract
The amount of the toxic waste generated in the hospitals and medical facilities is steadily increasing. Although, the centralized disposal or waste management service solutions for the removal of toxic waste are available in highly developed industrialized countries; this does not, however, apply to the developing and emerging countries. For this reason, a compact sterilization and shredding machine was developed. The steam sterilization used (temperatures of 134 °C + 4 K and pressures of 480 to 3500 mbar) complies with the recognized procedure of the Robert Koch Institute (without chemical substances). Thus, it was possible to transform the infectious or toxic waste into non-hazardous household waste. The microbiological and physical test results show that the machine meets the requirements for sterilization of class C solid and liquid clinical wastes. The capacity of the machine is maximum 400 liters of waste per cycle, with an average cycle time of about 1 hour. It is possible to process contaminated materials both loose and in sealed disposal containers (C-boxes).
Improved Global Navigation Satellite System filtering methods for the mobile six-minute walk test
Authors: Ogris Maximilian , Edegger Kurt , Rzepka Angelika , Ziegl Andreas , Schreier Günter 
Published: September 2022

Abstract
Heart failure (HF) is a chronic disease with high hospitalizations rates and increased mortality. The six-minute walk test (6MWT) is a standardized method to assess the functional health of HF patients by measuring the distance walked in six minutes [1]. The improved 6MWT with new filter algorithms, based on the development of smartphone application [9], can be used everywhere with a good global navigation satellite system (GNSS) signal. This paper tests multiple filtering approaches to reduce the measured distance error in the application.We were able to decrease the average relative error of the application from 4.5% to 2.0%. Additionally, the number of experiments with relative error over our chosen clinically significant difference of 5% is reduced by 90%. Keeping these results in mind, the system can be considered clinically acceptable.
A concept and technical requirements for the Temi platform supporting care and nursing
Authors: Weigand Christian , Flemming Daniel , Zweyer Georg , Borutta Paul , Hofmann Fabian , Wieland Georg , Hayir Erdem , Seuß Dominik , Wittenberg Thomas 
Published: September 2022

Abstract
With a growing number of people in need of care and the shortage of skilled workers, caregivers express the desire for improved support to reduce physical strain and psychological stress. One task for burden relieve is documentation of nursing actions and treatment processes, as this can be done in parallel with the action. Hence tools capturing information in real time could improve information sharing. Also, contactless assessment of patients’ vital signs and emotions is desirable. Thus, the idea is to enhance an existing mobile platform, which can follow the nurse, includes a voice-controlled assistant, and be able for wireless (e.g., via Bluetooth) assessment of vital data from patients in its direct vicinity. Using the Temi telepresence robot as an open technical platform, we provide and discus requirements for this platform to potentially aid and relief to medical staff within caring and elderly homes, with respect to voice-control, Bluetooth-based vital data collection, interfaces to a digital patient manager and automated emotion recognition. The presented concept and the rating of the associated technologies leads to the conclusion that - if adequately implemented and installed - the caregivers could potentially receive noticeable relief from them. Nevertheless, as next steps, the examined technologies and ideas must be completely implemented, thoroughly fused with each other, and evaluated to provide a real support system for clinical care and assisted documentation.
Investigation of everyday influencing factors on the variability of exhaled breath profiles in healthy subjects
Authors: Fachet Melanie , Lowitzki Simon , Reckzeh Marie-Louise , Walles Thorsten , Hoeschen Christoph 
Published: September 2022

Abstract
Introduction: The human breath is an accurate but complex read-out of many physiological processes in the organism that can be monitored via volatile organic compounds (VOCs) in the exhaled air. However, there are many confounding variables that limit the transfer and application of breath analysis to become a clinical procedure. Method: This work aims to establish a systematic procedure for sampling and characterization of various everyday influences of healthy subjects using proton transfer reaction-mass spectrometry (PTR-MS). In order to limit the influencing factors on the breath profile, a standard analysis procedure for sampling and evaluation of the exhaled breath samples was developed. The correlations between the selected experimental conditions and the resulting VOC profiles were investigated using a non-parametric Wilcoxon rank sum test. Results: In addition to the relevant influence of methodological experimental parameters, interesting insights into the effect of everyday factors on the exhalat gas were obtained and discussed. Furthermore, subject and condition-specific differences were found in the exhaled air of male and female subjects. Conclusion: With a more robust, standardized and reproducible breath sampling protocol, breath analysis is a promising non-invasive tool towards a system-wide understanding and personalized diagnosis and treatment of a wide range of diseases.
Susceptibility artifacts evaluation for non-metallic biopsy needles in a biological-engineered 3D tumor model
Authors: Al-Maatoq Marwah , Fachet Melanie , Walles Heike , Hoeschen Christoph 
Published: September 2022

Abstract
Nowadays, needle artifacts are an essential restriction for MRI-guided interventions, as they influence the visually perceived needle size and needle destination. Standard MRI needles made of Nickel-Titanium (NiTi) alloys still produce massive artifacts in MRI due to materials’ interactions with the magnetic environment. The use of non-metallic materials can reduce these artifacts. Therefore, we propose a nonmetallic concept of a coaxial needle design concept with a fiber-enforced inner core and an outer polymeric hollow sheet. This work aims to evaluate the artifact performance of the proposed needles in a custom-made three-dimensional (3D) tumor model with a relevant size and thickness for medical interventions under MRI guidance using a 3T field strength with a T1-weighted gradient-echo sequence. Three coaxial MRcompatible needles were inserted in the custom-made 3D tissue phantom, one standard needle from NiTi, and two proposed non-metallic needles. Artifact’s width and length were measured for each needle. Overall, the non-metallic needles showed significantly lower artifacts than the standard NiTi needle inside the 3D tumor model.
Work space analysis of a new instrument for Natural Orifice Transluminal Endoscopic Surgery (NOTES)
Authors: Bachmann Ada L. , Giacoppo Giuliano A. , Pott Peter P. 
Published: September 2022

Abstract
Minimally invasive procedures such as Natural Orifice Transluminal Endoscopic Surgery (NOTES) require powerful, small, and flexible instruments. A cable-driven instrument was developed, which is able to retract tissue to create sufficient space for an actual operation (e.g. cholecystectomy). In this paper, the work space of a developed instrument is presented. The work space is calculated using direct kinematics equations and verified by measurement using an electromagnetic (EM) tracking system. The angular orientation of the instrument can be up to 85° with a length of the active section of 60 mm. However, a longitudinal rotation up to 17° becomes apparent. This is due to the characteristics of the steel cable used for actuation. Nevertheless, the instrument reaches the intended work space. Further measurements are necessary to evaluate the instrument’s behavior under payload and whether this affects the work space.
Evaluation of spatio-temporal electrocutaneous warning signals
Authors: Dölker Eva-Maria , Bernhard Maria Anne , Daniswara Indra , Haueisen Jens 
Published: September 2022

Abstract
Acoustic or visual warning signals for workers in hazardous situations might fail under loud and/or lowvisibility work situations. A warning system that uses electrocutaneous stimulation can overcome this problem. The aim of this pilot study was to find spatio-temporal stimulation patterns for appropriate electrical warning. Eight electrode pairs were attached to the upper right arm of 16 participants. The stimulation was conducted with bi-phasic rectangular pulses of 150 μs and an amplitude of up to 25 mA. Pulse intervals that generate a single pulse, pulsating, vibrating, and continuous perception as well as varying spatial patterns (e.g. alternating between electrode pairs or circumferentially around the arm) were investigated and evaluated with regard to alertness, discomfort, and urgency. The pilot study revealed that a stimulation signal that generates a vibrating perception and is applied as a circumferential signal around the arm showed the highest values of alertness and is therefore considered a potential warning pattern for future studies with larger study groups.
Differentiation of COVID-19 Conditions using Mediastinum Shape in Chest X-ray Images
Authors: Kumar Tulo Sukanta , Govindarajan Satyavratan , Ramu Palaniappan , Swaminathan Ramakrishnan 
Published: September 2022

Abstract
In this work, an attempt has been made to analyze the shape variations in mediastinum for differentiation of Coronavirus Disease-2019 (COVID-19) and normal conditions in chest X-ray images. For this, the images are obtained from a publicly available dataset. Segmentation of mediastinum from the raw images is performed using Reaction Diffusion Level Set (RDLS) method. Shape-based features are extracted from the delineated mediastinum masks and are statistically analyzed. Further, the features are fed to two classifiers, namely, multi-layer perceptron and support vector machine for differentiation of normal and COVID-19 images. From the results, it is observed that the employed RDLS method is able to delineate mediastinum from the raw chest Xray images. Eight shape features are observed to be statistically significant. The mean values of these features are found to be distinctly higher for COVID-19 images as compared to normal images. Area under the curve of greater than 76.9% is achieved for both the classifiers. It appears that mediastinum could be used as a region of interest for computerized detection and mass screening of the disease.
IEEE 11073 SDC for Pandemics like COVID-19: Example Implementation of an Isolation Room
Authors: Kasparick Martin , Schackmann Dennis , Klotz Tobias , Ritz Fabian , Golatowski Frank , Rethfeldt Michael , Neumuth Thomas , Timmermann Dirk , Rockstroh Max 
Published: September 2022

Abstract
Treating patients in an intensive care unit (ICU) isolation room is full of challenges for the caregivers and the patients. While this is known for years, the COVID-19 pandemic has highlighted these challenges as if under a burning glass - intensified by a high number of patients at the same time. The risk of infection for the caregivers is very high inside the isolation room and the time spent for putting on and taking off personal protective equipment (PPE) is enormous. Thus, every treatment that can be performed from the anteroom of the isolation room at the same quality level as if being inside the isolation room is a potential building block for solving the challenges. However, data like vital signs have to be provided to the anteroom, alarms have to be transferred to the right caregiver at the right place, and controlling medical device parameters from the anteroom are prerequisites. The new IEEE 11073 Service-oriented Device Connectivity (SDC) series of standards is a key technology to realize this. Therefore, this paper presents an example implementation of IEEE 11073 SDC-based ICU isolation rooms by means of a demonstrator. Such systems can significantly reduce the amount of time the caregivers have to spend in the isolation room and reduce the number of clothing (PPE) changes while providing care at a level of a non-isolation room. As a midterm goal these are steps for the vision of a “silent/quiet ICU”.
Thermal annealing of injection molded VHMW PLLA
Authors: Oschatz Stefan , Arbeiter Daniela , Schultz Selina , Fiedler Nicklas , Grabow Niels 
Published: September 2022

Abstract
In this study, DSC experiments were used to elaborate an annealing protocol for injection molded very high molecular weight (VHMW) PLLA with two molecular masses, 320,000 g/mol and 700,000 g/mol. The initial material obtained from the injection molding process was found to be highly amorphous and not in thermodynamic equilibrium state, as distinct cold crystallization and enthalpy relaxation were observed in DSC data. Thermal annealing to 85 °C for 60 - 90 min under controlled conditions using a DSC device showed to be sufficient to stabilize the polymer and increase the crystallinity to up to 50 %. Annealing did not result in any signs of thermal decomposition. The elaborated thermal treatment has been transferred to manual annealing of large specimen geometries for subsequent DMA analysis.
Design study of dynamic mechanical test bench specimen grips
Authors: Fiedler Nicklas , Arbeiter Daniela , Kleine Thomas , Grabow Niels 
Published: September 2022

Abstract
The characterization of mechanical properties of materials used in biomedical applications is essential for performance evaluation. In addition to quasi-static tests, dynamic tests extend the range of methods and allow predictions of failure, as well as information on durability. Appropriate specimen grips according to the test sample geometry are crucial for a reliable examination of mechanical testing and therefore valid experimental data. In particular, the investigation of polymers is challenging, as properties show major differences depending on temperature and applied loading rate. This could result in slipping or tearing of samples in the specimen grip area. Numerical simulations of reference grips, as well as alternative custom designs, were performed evaluating damage due to the clamping process and to provide appropriate specimen grips for future dynamic-mechanical investigations of materials with variable properties. Both the results of the numerical simulation and preliminary tests with 3D-printed prototypes show a distinct improvement in specimen clamping. Plastic deformation and local stress peaks were reduced while maintaining the same tightening torque.
PLLA crystallization kinetics in dependence of molecular weight
Authors: Arbeiter Daniela , Grabow Niels , Oschatz Stefan 
Published: September 2022

Abstract
The effect of molecular weight Mwon the polymorphous crystallization and melting behavior of poly(Llactide) PLLA (L206, L210 and L214) were systemically studied by differential scanning calorimetry (DSC). Melting and reorganization of conformationally disordered crystals (α′-phase) of PLLA are analyzed with respect to the cooling rate qcin a range between about 4 and 50 K/min and the heating rate qhin a range between about 5 and 200 K/min. It was shown that the α′- to α-crystalline phase transition prior to the dominant melting depends on cooling rate qcand Mw. Unlike very high-MwPLLA L214, for low-MwPLLA L206 crystallized at high qc, the α′-form crystals only partially transformed into the α-modification, and certain amounts of α′-form crystals melted directly without α′- to α-transition during the heating process. With increasing qc, the melting of PLLA L210 changed from phase-transition- and -melting mechanism to the common melt-recrystallization mechanism. It was also found that the polymorphism of PLLA significantly affected the crystallization kinetics. Consequently, the reorganization of α′-crystals into stable α- crystals could be inhibited by fast heating (qh> 150 K/min).