An Easy-to-Use Protocol for Segmenting and 3-D Printing Craniofacial CT-Images Using Open-Source Software

Introduction: Stereolithography, also known as 3D printing (3DP), is a versatile and useful technology with many healthcare applications. While 3DP has gained tremendous popularity, it remains a daunting and perceptibly time-consuming process for the inexperienced user, with most turning to commercially printed products. Commercial vendors are expensive. We propose that 3DP is feasible for the inexperienced user with the appropriate knowledge and tools. Methods: A 3DP protocol was created for model design and printing using open-source software and a low-cost desktop printer. It was betatested by 3 inexperienced users. The fidelity of the protocol was then tested in direct comparison to industry models made for 3 patients undergoing mandibular distraction osteogenesis, using standard cephalometric measurements. Results: All inexperienced testers were able to successfully create a 3D model using the easy-to-follow protocol without the use of any other resources. The models were created in a mean time of 170 minutes. All cephalometric measurements on the open-source printed models were equal to within 0.5 to 1.0 mm of the respective industry models. Conclusions: As the 3DP process is simplified and desktop printers and materials become more affordable, we anticipate that its implementation will become more commonplace. We describe a step-by-step, protocol using open-source software and affordable materials to create 3D models.

A Wi-Fi–Based Mask-Type Laryngoscope for Telediagnosis During the COVID-19 Pandemic: Instrument Validation Study (Preprint)

BACKGROUND Owing to the COVID-19 pandemic, social distancing has become mandatory. Wireless endoscopy in contactless examinations promises to protect health care workers and reduce viral spread. OBJECTIVE This study aimed to introduce a contactless endoscopic diagnosis system using a wireless endoscope resembling a mask. METHODS The Wi-Fi–based contactless mask endoscopy system comprises a disposable endoscope and a controller. First, the effective force applied by the tip during insertion was evaluated in a simple transoral model consisting of a force sensor on a simulated oropharynx wall. Second, the delay in video streaming was evaluated by comparing the frame rate and delays between a movement and its image over direct and Wi-Fi connections. Third, the system was applied to a detailed laryngopharyngeal tract phantom. RESULTS The smartphone-controlled wireless endoscopy system was successfully evaluated. The mean, maximum, and minimum collision forces against the wall of the transoral model were 296 mN (30 gf), 363 mN (37 gf), and 235 mN (24 gf), respectively. The delay resulting from the wireless connection was 0.72 seconds. Using the phantom, an inexperienced user took around 1 minute to orient the endoscope to a desired area via the app. CONCLUSIONS Device articulation does not pose a significant risk of laryngopharyngeal wall penetration, and latency does not significantly impede its use. Contactless wireless video streaming was successful within the access point range regardless of the presence of walls. The mask endoscope can be controlled and articulated wirelessly, minimizing contact between patients and device operators. By minimizing contact, the device can protect health care workers from infectious viruses like the coronavirus. CLINICALTRIAL

Reliability and minimal detectable change of the ‘Imperial Spine’ marker set for the evaluation of spinal and lower limb kinematics in adults

Objectives As a step towards the comprehensive evaluation of movement in patients with low back pain, the aim of this study is to design a marker set (three rigid segment spine, pelvic and lower limb model) and evaluate the reliability and minimal detectable change (MDC) of this marker set in healthy adults during gait and sit to stand (STS) tasks using three dimensional motion capture. Results The ‘Imperial Spine’ marker set was used to assess relative peak angles during gait and STS tasks using the minimum recommended sample size (n = 10) for reliability studies with minimum Intraclass Correlation Coefficient (ICC) of 0.70, optimum ICC 0.90 and 9 trials replicated per subject per task. Intra- and inter-tester reliability between an experienced and inexperienced user was examined. ICC, mean, standard error (SEM), Bland Altman 95% limits of agreement (LOA) and MDC were computed. ICC values demonstrated excellent intra- and inter-tester reliability in both tasks, particularly in the sagittal plane (majority ICCs > 0.80). SEM measurements were lower in gait (0.8–5.5°) than STS tasks (1°-12.6°) as were MDC values. LOA demonstrated good agreement. The ‘Imperial Spine’ marker set is reliable for use in healthy adults during functional tasks. Future evaluation in patients is required.

Incorrect Simulation Results in OpenModelica

An adequacy of mathematical modelling of the technical object dynamics is always a challenge, and a user can make up his mind about the modelling package using simple test schemes. The article presents the schemes that are quite common from the point of view of an inexperienced user, but have specifics in mathematical modelling. The features of the schemes are that therein failures of equilibrium equations (such as the first Kirchhoff law) and continuity (such as the second Kirchhoff law) can occur. These features can lead to incorrect results when using the OpenModelica package, while the domestic PA9 and PRADIS packages used in modelling these schemes give the correct result. The article presents two simple schemes, the simulation result of which can be a priori estimated, and provides simulation results for three packages - OpenModelica, PA9, and PRADIS.

Simplified Analysis for Multiple Input Systems: A Toolbox Study Illustrated on F-16 Measurements

This paper introduces a nonparametric, nonlinear system identification toolbox called SAMI (simplified analysis for multiple input systems) developed for industrial measurements of vibro-acoustic systems with multiple inputs. It addresses the questions related to the user-friendly (semi-)automatic processing of multiple-input, multiple-output measurements with respect to the design of an experiment and the analysis of the measured data. When the proposed toolbox is used, with minimal user interaction, it is easily possible (a) to decide whether the underlying system is linear or not, (b) to decide whether the linear framework is still adequate to be used, and (c) to tell an inexperienced user how much can be gained using an advanced nonlinear framework. The toolbox is illustrated on openly accessible F-16 ground vibration testing measurements.

A user-friendly, high-throughput tool for the precise fluorescent quantification of deoxyribonucleoside triphosphates from biological samples

Cells maintain a fine-tuned, dynamic concentration balance in the pool of deoxyribonucleoside 5′-triphosphates (dNTPs). This balance is essential for physiological processes including cell cycle control or antiviral defense. Its perturbation results in increased mutation frequencies, replication arrest and may promote cancer development. An easily accessible and relatively high-throughput method would greatly accelerate the exploration of the diversified consequences of dNTP imbalances. The dNTP incorporation based, fluorescent TaqMan-like assay published by Wilson et al. has the aforementioned advantages over mass spectrometry, radioactive or chromatography based dNTP quantification methods. Nevertheless, the assay failed to produce reliable data in several biological samples. Therefore, we applied enzyme kinetics analysis on the fluorescent dNTP incorporation curves and found that the Taq polymerase exhibits a dNTP independent exonuclease activity that decouples signal generation from dNTP incorporation. Furthermore, we found that both polymerization and exonuclease activities are unpredictably inhibited by the sample matrix. To resolve these issues, we established a kinetics based data analysis method which identifies the signal generated by dNTP incorporation. We automated the analysis process in the nucleoTIDY software which enables even the inexperienced user to calculate the final and accurate dNTP amounts in a 96-well-plate setup within minutes.

Automatic Reproduction of Natural Head Position Using a Portable 3D Scanner Based on Immediate Calibration

This paper developed a new method to easily record and automatically reproduce the 3D natural head position (NHP) of patients using a portable 3D scanner based on immediate calibration. We first optically scanned the patient’s face using a portable 3D scanner, and the scanned model was easily aligned with the global horizon based on an immediate calibration procedure using a developed calibration plate. The 3D patient NHP Computed Tomography(CT) model was reproduced automatically by performing registration between the CT model and the optically scanned model in the NHP using a modified coherent point drift (CPD) algorithm. In a phantom experiment, we evaluated the developed method’s accuracy using the error between the true and the calculated orientations in roll, pitch, and yaw directions. The mean difference was −0.05 ± 0.13°, 0.08 ± 0.22°, and −0.05 ± 0.18° in the roll, pitch, and yaw directions, respectively. The measured roll, pitch, and yaw directions were not significantly different from the true directions (p > 0.05). The calibration procedure for aligning the scanner coordinate system was easy enough for an inexperienced user to operate, and the 3D NHP CT model could be reproduced automatically. The developed method could be used for diagnosing and treating orthognathic patients with facial asymmetry accurately and conveniently in dental clinics.

A Perceptual Computing Based Gesture Controlled Quadcopter for Visual Tracking and Transportation

One of the fundamental challenges faced by an inexperienced user in portable unmanned aerial vehicle (UAV) such as quadcopters is flight control, often leading to crashes. Addressing this challenge, and leveraging upon the technological advancement in perceptual computing and computer vision, this research presents a modular system that allows for hand gesture based flight control of UAV, alongside a transport mechanism for portable objects. In addition to ascertain smooth flight control by avoiding obstacles in navigation path, real-time video feedback is relayed from the UAV to user, thus allowing him/her to take appropriate actions. This paper presents the design implementation by discussing the various sub-systems involved, inter system communication, and field tests to ascertain operation. As presented from testing results, the proposed system provides efficient communication between the subsystems for smooth flight control, while allowing for safe transport of portable objects.

PRINCIPLES OF DEVELOPING A USER INTERFACE FOR MOBILE MAPPING APPLICATIONS

The article deals with the development of a user interface for mobile mapping applications. For the inexperienced user, a convenient and attractive user interface is one of the main conditions for successful work with a mobile cartographic application, so it is necessary to consider in detail the question of what exactly such an interface should become. Taking into account the analysis and existing experience in the development of interfaces for working with cartographic applications, all the general requirements for interfaces of mobile applications were collected and considered in order to identify and formulate the basic principles necessary for the development of an interface of cartographic applications. The proposed principles can be divided into three groups: principles defining the general issues of building the interface of mobile mapping applications, their structure as a whole, and user interaction; principles defining the design of the interface of mobile mapping applications; principles defining the development of mobile mapping applications, taking into account the peculiarities of their use and new technical capabilities.

OpenZmeter: An Efficient Low-Cost Energy Smart Meter and Power Quality Analyzer

Power quality and energy consumption measurements support providers and energy users with solutions for acquiring and reporting information about the energy supply for residential, commercial, and industrial sectors. In particular, since the average number of electronic devices in homes increases year by year and their sensitivity is very high, it is not only important to monitor the total energy consumption, but also the quality of the power supplied. However, in practice, end-users do not have information about the energy consumption in real-time nor about the quality of the power they receive, because electric energy meters are too expensive and complex to be handled. In order to overcome these inconveniences, an innovative, open source, low-cost, precise, and reliable power and electric energy meter is presented that can be easily installed and managed by any inexperienced user at their own home in urban or rural areas. The system was validated in a real house over a period of two weeks, showing interesting results and findings which validate our proposal.