Initial Prototype Research Articles

Prototype Development of Final Year Project Management System to Monitor Student’s Performance

The university requires students to complete a comprehensive software development project in their final year of study in all Information Technology (IT) and Computer Science (CS) programmes, run by the Faculty of Computing & Multimedia (FCOM), Universiti Poly-Tech Malaysia. As the number of students increases by semester, manual procedures for managing student projects become a major issue. Ineffective supervision and monitoring of student progress are more likely to occur as the number of students to supervise per lecturer also increase. This circumstance may contribute to an increase in the number of students who will fail to complete project development within the time frame specified. A log book is currently used to document meetings and discussions between supervisors and students. Although a detailed schedule has been proposed, a monitoring process that triggers specific actions to ensure all deadlines are met is required. The objective of this research is to improve project monitoring and supervision by developing a prototype of a web-based Final Year Project Management System (FYPMS). The initial prototype is built on the dashboard approach concept, where students can see their progress and lecturers can use this centralized system to monitor students' performance. This system’s users are divided into three groups: students, lecturers, and coordinators where they can communicate efficiently and effectively by using this system. By using the FYPMS, the faculty can look forward to better project management, improved supervision, fewer project delays, and a more efficient final year project process.

User Requirements in Developing a Novel Dietary Assessment Tool for Children: Mixed Methods Study.

The prevalence of childhood obesity and comorbidities is rising alarmingly, and diet is an important modifiable determinant. Numerous dietary interventions in children have been developed to reduce childhood obesity and overweight rates, but their long-term effects are unsatisfactory. Stakeholders call for more personalized approaches, which require detailed dietary intake data. In the case of primary school children, caregivers are key to providing such dietary information. However, as school-aged children are not under the full supervision of one specific caregiver anymore, data are likely to be biased. Recent technological advancements provide opportunities for the role of children themselves, which would serve the overall quality of the obtained dietary data. This study aims to conduct a child-centered exploratory sequential mixed methods study to identify user requirements for a dietary assessment tool for children aged 5 to 6 years. Formative, nonsystematic narrative literature research was undertaken to delineate initial user requirements and inform prototype ideation in an expert panel workshop (n=11). This yielded 3 prototype dietary assessment tools: FoodBear (tangible piggy bank), myBear (smartphone or tablet app), and FoodCam (physical camera). All 3 prototypes were tested for usability by means of a usability task (video analyses) and user experience (This or That method) among 14 Dutch children aged 5 to 6 years (n=8, 57% boys and n=6, 43% girls). Most children were able to complete FoodBear's (11/14, 79%), myBear's (10/14, 71%), and FoodCam's (9/14, 64%) usability tasks, but all children required assistance (14/14, 100%) and most of the children encountered usability problems (13/14, 93%). Usability issues were related to food group categorization and recognition, frustrations owing to unsatisfactory functioning of (parts) of the prototypes, recall of food products, and the distinction between eating moments. No short-term differences in product preference between the 3 prototypes were observed, but autonomy, challenge, gaming elements, being tablet based, appearance, social elements, and time frame were identified as determinants of liking the product. Our results suggest that children can play a complementary role in dietary data collection to enhance the data collected by their parents. Incorporation of a training program, auditory or visual prompts, reminders and feedback, a user-friendly and intuitive interaction design, child-friendly food groups or icons, and room for children's autonomy were identified as requirements for the future development of a novel and usable dietary assessment tool for children aged 5 to 6 years. Our findings can serve as valuable guidance for ongoing innovations in the field of children's dietary assessment and the provision of personalized dietary support.

Three-Dimensional Printed Annular Ring Aperture-Fed Antenna for Telecommunication and Biomedical Applications

The design of the aperture-fed annular ring (AFAR) microstrip antenna is presented. This proposed design will ease the fabrication and usability of the 3D-printed and solderless 2D materials. This antenna consists of three layers: the patch, the slot within the ground plane as the power transfer medium, and the microstrip line as the feeding. The parameters of the proposed design are investigated using the finite element method FEM to achieve the 50 Ω impedance with the maximum front-to-back ratio of the radiation pattern. This study was performed based on four steps, each investigating one parameter at a time. These parameters were evaluated based on an initial design and prototype. The optimized design of 3D AFAR attained S11 around 17 dB with a front-to-back ratio of more than 30 dB and a gain of around 3.3 dBi. This design eases the process of using a manufacturing process that involves 3D-printed and 2D metallic materials for antenna applications.

Rapid prototyping of FBG-based optical sensors for vibration analysis of mechatronic systems

The detection and study of vibrations play a fundamental role in the monitoring and safety of engineering systems. This is especially true in the aerospace sector, where the operating environment is often hostile, and the constraints on weights and dimensions are very tight. For these reasons, the research and application of sensors based on optical signal transmission are becoming increasingly important. The opportunity to implement distributed measurements along a single optical fiber, the small size and weight, and the high resistance to electromagnetic interference make this technology an ideal candidate for the development of next-generation aerial platforms. In this paper, the authors focus on designing and developing a novel sensor that employs Fiber Bragg Grating (FBG) for vibration detection. Their primary aim is to explore the potential and constraints of this technology and build an initial prototype for testing purposes. Additionally, the project enabled the authors to experiment with rapid prototyping techniques that rely on 3D printing and additive manufacturing. The impact of various design choices, such as materials, geometry, and manufacturing, on the demonstrator sensitivity was explored by analysing the problem mathematically. A Matlab script was developed to estimate dimensions, weights, and dynamic performances, and modelling FEM was used for validation.

A novel semi-supervised prototype network with two-stream wavelet scattering convolutional encoder for TBM main bearing few-shot fault diagnosis

Accurately sensing the main bearing state and diagnosing fault types is crucial to ensure the safe operation of the main drive system of tunnel boring machines. Currently, the research on large-scale bearing fault diagnosis in industrial scenarios is severely limited by the quality and quantity of monitoring data. Conventional external vibration monitoring devices are difficult to adapt to complex and harsh working conditions of excavation equipment, and constantly changing low-speed and heavy-load operating conditions make similar labeled samples very scarce. To tackle this concern, we propose a semi-supervised prototype network with the two-stream wavelet scattering convolutional encoder (TWSCE-SSPN) based on roller state signals. By fusing radial and axial features of rollers using the two-stream structure and employing wavelet scattering transform and attention mechanism in the convolutional feature encoder, the model exhibits excellent feature mapping capabilities. Following the semi-supervised meta-learning paradigm, the proposed model uses the prototype generated by unlabeled sample features to modify the initial prototype generated by labeled sample features to augment the accuracy of classification in few-shot learning. The integrated sensing roller main bearing testbed was set up and fault datasets were established to verify the few-shot classification and anti-noise ability of the algorithm. Experimental results show that TWSCE-SSPN achieved 98.17 % accuracy at 1 shot, which is at least 18.17 % higher than existing methods. Furthermore, even under a signal-to-noise ratio of 0 dB, the few-shot recognition accuracy can remain 91.83 %. This verifies the superiority of the model in diagnosing main bearing faults under few-shot and strong noise conditions.

Hazardous and Toxic Material Decontamination Facility Training in Virtual Reality

Patient decontamination is the act of removing or neutralising hazardous substances from an affected individual. To ensure adequate emergency preparedness, regulations require hospitals to train personnel in decontamination procedures regularly. To supplement in-person training, a virtual reality (VR) system is being developed for the training of hospital staff members in the mass decontamination of hazardous and toxic materials (HAZMAT) and/or radioactively contaminated casualties. As a demonstration of the concept, a primary VR prototype is designed to help users familiarize themselves with a chemical scanner tool, intended for examining victims for residual chemical hazards. This initial prototype showcases the benefits of using VR to create training simulations, complementing existing decontamination training methods in a secure and cost-effective manner. The proposed approach features a modularized user-centric design, a novel scanning simulation, and a high-realism virtual environment and workflow to enhance training effectiveness. A pilot user study and assessment suggest that new users were able to achieve a significant level of competency with VR, compared to users who underwent traditional training.

Kinase inhibitor pulldown assay (KiP) for clinical proteomics

Protein kinases are frequently dysregulated and/or mutated in cancer and represent essential targets for therapy. Accurate quantification is essential. For breast cancer treatment, the identification and quantification of the protein kinase ERBB2 is critical for therapeutic decisions. While immunohistochemistry (IHC) is the current clinical diagnostic approach, it is only semiquantitative. Mass spectrometry-based proteomics offers quantitative assays that, unlike IHC, can be used to accurately evaluate hundreds of kinases simultaneously. The enrichment of less abundant kinase targets for quantification, along with depletion of interfering proteins, improves sensitivity and thus promotes more effective downstream analyses. Multiple kinase inhibitors were therefore deployed as a capture matrix for kinase inhibitor pulldown (KiP) assays designed to profile the human protein kinome as broadly as possible. Optimized assays were initially evaluated in 16 patient derived xenograft models (PDX) where KiP identified multiple differentially expressed and biologically relevant kinases. From these analyses, an optimized single-shot parallel reaction monitoring (PRM) method was developed to improve quantitative fidelity. The PRM KiP approach was then reapplied to low quantities of proteins typical of yields from core needle biopsies of human cancers. The initial prototype targeting 100 kinases recapitulated intrinsic subtyping of PDX models obtained from comprehensive proteomic and transcriptomic profiling. Luminal and HER2 enriched OCT-frozen patient biopsies subsequently analyzed through KiP-PRM also clustered by subtype. Finally, stable isotope labeled peptide standards were developed to define a prototype clinical method. Data are available via ProteomeXchange with identifiers PXD044655 and PXD046169.

Conversation-based hybrid UI for the repertory grid technique: A lab experiment into automation of qualitative surveys

A frequent use of conversational user interfaces (CUIs) today is improving the users’ experience with online quantitative surveys. In this paper, we explore the use of CUIs in qualitative surveys. As a concrete use case, we adopt a specific, well-structured, qualitative research method called the repertory grid technique (RGT). We developed a hybrid user interface (HUI) that combines a graphical user interface (GUI) with a CUI to automate the distinct stages in a RGT survey. A pilot study was used to verify the feasibility of the approach and to fine-tune interface aspects of an initial prototype. In this paper, we report the results of a within-subject lab experiment with 24 participants that aimed to establish the performance and UX in a realistic context of a more advanced prototype. We observed a small decrease in UX in some hedonistic aspects, but also confirmed that the HUI performs similarly to a human agent in most pragmatic aspects. These results provide support for our hypothesis that automating qualitative surveys is possible with proper interface design. We hope that our work can inspire other researchers to design additional tools for qualitative survey automation, especially now that generative AI systems, such as ChatGPT, open up interesting new ways for computer systems to interact with users in natural language.

Promoting Stress Management among Students in Higher Education: Evaluating the Effectiveness of a Persuasive Time Management Mobile App

In recent years, there has been a notable rise in the development of mobile apps to deliver stress management interventions. However, the prevailing design of most available stress management apps leans towards an emotion-focused coping approach, primarily targeting the regulation of stress-induced negative emotions. Given that the perception of time shortage is a major source of stress among students in higher education, we adopted a problem-focused coping approach that targets tackling student stress via time management. Our work evolved through four main phases. First, we previously conducted a large-scale study involving 502 students, constructing five structural equation models (SEMs) to pinpoint the most effective time management factor in promoting the perception of control over time. Second, based on the findings, we designed and developed a persuasive mobile app (SortOut) to promote effective time management behavior among the target users. Before the development phase, the initial app prototype was evaluated and refined with students (n = 69). In the final phase, this paper focuses on the culmination of our work, wherein we assessed the app’s effectiveness through a 4-week field study involving 34 students. Subsequently, we conducted one-on-one interviews with 11 students to delve into their experiences and feedback. The results revealed that, after using the app, students demonstrated improvement in time management behavior, higher academic self-confidence, and lower stress compared to the baseline. Students in the early and later stages of behavior change (based on the Transtheoretical Model (TTM)) reported similar positive outcomes. Moreover, students perceived the app as straightforward and easy to use; they were not tense or pressured while using the app, which is especially vital for stress management interventions. Thematic analysis showed that the app encouraged organizational thought and behavior and aided students in managing their time and workload, increasing the commitment toward task completion. The study findings suggest that the app helped students engage in effective time management behavior with an improved perception of control over time. Such improved perception is instrumental in promoting student confidence and well-being. Guided by the study findings, we provided actionable design recommendations and future research directions to facilitate the development of impactful persuasive time and stress management interventions.

The “Effect of Marangoni Convection on Heat Transfer in Phase Change Materials” experiment: Design and performance of the cuboidal cell

The experiment “Effect of Marangoni Convection on Heat Transfer in Phase Change Materials” aims to investigate the efficacy of thermal Marangoni convection in augmenting the heat transfer rate of passive phase change materials (PCMs) that incorporate a free surface in microgravity; the so-called thermocapillary-enhanced PCMs. Compared to thermal conduction, thermocapillary flows can increase heat transport by a factor of two or more. In addition to advancing scientific understanding, the experiment seeks to evaluate the practical feasibility of using thermocapillary-enhanced PCMs as passive thermal control devices for space missions and assess possible implementation challenges. By analyzing different PCM samples, the experiment will provide crucial insights into the heat and mass transport mechanisms of thermocapillary flows during melting and solidification. The present article primarily describes the design, thermal control and ground results of the cuboidal cell of the experiment. We illustrate here the comprehensive approach towards developing space experiments adhering to rigorous and demanding scientific and technical requirements. Along with the validation of an initial experiment prototype, the evaluation of ground tests is also addressed. The hardware developed demonstrates an adequate performance, while the obtained scientific results are coherent and compliant with the established requirements; the feasibility of the proposed design is thus demonstrated.

Exploration of Film and Television Cultural Communication Strategies in the Digital Era

Abstract Based on the information digital technology and Internet platform of new media, this paper discusses how they accelerate the change of film and television culture communication. This paper first constructed a clustering index system for film and television culture communication, then adopted the improved K-prototype algorithm to determine the clustering center, and calculated the distance between the research data and the initial prototype. Then, the total loss function is used to cluster the data. The Analysis shows that between 2013 and 2023, the box office of movies and TV shows will increase by an average of 616 million yuan per year, and the number of moviegoers will increase by 958 million in 11 years. The study also found that the themes of entertainment (p=0.004<0.05) and traditional culture (p=0.042<0.05) had a significant negative impact on the breadth of communication. In contrast, the themes of treasure hunting and adventure (p=0.006<0.05) significantly negatively affected communication participation. Based on these findings, the paper puts forward suggestions for the future development of film and television culture communication strategies, which provides a valuable reference for the practice and data support of film and television culture communication.

STELO: A New Modular Robotic Gait Device for Acquired Brain Injury-Exploring Its Usability.

In recent years, the prevalence of acquired brain injury (ABI) has been on the rise, leading to impaired gait functionality in affected individuals. Traditional gait exoskeletons are typically rigid and bilateral and lack adaptability. To address this, the STELO, a pioneering modular gait-assistive device, was developed. This device can be externally configured with joint modules to cater to the diverse impairments of each patient, aiming to enhance adaptability and efficiency. This study aims to assess the safety and usability of the initial functional modular prototype, STELO, in a sample of 14 ABI-diagnosed participants. Adverse events, device adjustment assistance and time, and gait performance were evaluated during three sessions of device use. The results revealed that STELO was safe, with no serious adverse events reported. The need for assistance and time required for device adjustment decreased progressively over the sessions. Although there was no significant improvement in walking speed observed after three sessions of using STELO, participants and therapists reported satisfactory levels of comfort and usability in questionnaires. Overall, this study demonstrates that the STELO modular device offers a safe and adaptable solution for individuals with ABI, with positive user and therapist feedback.

MamoRef: an optical mammography device using whole-field CW diffuse reflectance. Presentation, validation and preliminary clinical results

Objective. MamoRef is an mammography device that uses near-infrared light, designed to provide clinically relevant information for the screening of diseases of the breast. Using low power continuous wave lasers and a high sensitivity CCD (Charge-coupled device) that captures a diffusely reflected image of the tissue, MamoRef results in a versatile diagnostic tool that aims to fulfill a complementary role in the diagnosis of breast cancer providing information about the relative hemoglobin concentrations as well as oxygen saturation. Approach. We present the design and development of an initial prototype of MamoRef. To ensure its effectiveness, we conducted validation tests on both the theoretical basis of the reconstruction algorithm and the hardware design. Furthermore, we initiated a clinical feasibility study involving patients diagnosed with breast disease, thus evaluating the practical application and potential benefits of MamoRef in a real-world setting. Main results. Our study demonstrates the effectiveness of the reconstruction algorithm in recovering relative concentration differences among various chromophores, as confirmed by Monte Carlo simulations. These simulations show that the recovered data correlates well with the ground truth, with SSIMs of 0.8 or more. Additionally, the phantom experiments validate the hardware implementation. The initial clinical findings exhibit highly promising outcomes regarding MamoRef’s ability to differentiate between lesions. Significance. MamoRef aims to be an advancement in the field of breast pathology screening and diagnostics, providing complementary information to standard diagnostic techniques. One of its main advantages is the ability of determining oxy/deoxyhemoglobin concentrations and oxygen saturation; this constitutes valuable complementary information to standard diagnostic techniques. Besides, MamoRef is a portable and relatively inexpensive device, intended to be not only used in specific medical imaging facilities. Finally, its use does not require external compression of the breast. The findings of this study underscore the potential of MamoRef in fulfilling this crucial role.

Development of a Biology E-Module Based on Google Sites on Circulatory System and Digestive System Material

Technological developments have a big influence on the learning process. Various positive influences can be seen with technological developments, one of which is electronic learning media. The existence of electronic-based media has a positive impact on learning because of the various advantages it has. In reality in the field, there are still many biology teachers who do not use electronic learning media in the learning process. Learning media that does not utilize technology tends not to attract students' attention due to its monotonous nature. Based on these reasons, researchers developed electronic learning media in the form of e-modules based on Google sites. E-module is able to visualize and clarify various abstract concepts. E-modules can help teachers to facilitate students in learning and support the learning process. The development of a Google Sites-based e-module was created using the Plomp model which consists of 3 stages, namely the initial investigation stage (preliminary research), the development or prototyping phase (development or prototyping phase), and the assessment phase (assessment phase). The results of the e-module development show that the overall validation value of the Google Sites-based e-module is 86.40% (very valid) from experts. Furthermore, the practicality assessment given by the teacher towards the Google Sites-based e-module showed an average result of 96.25% (very practical).

Prototyping an ionization source for non-engineers.

Novel mass spectrometry (MS) based analytical platforms have enabled scientists to detect and quantify molecules within biological and environmental samples more accurately. Novel MS instrumentation starts as a prototype and, after years of development, can become a commercial product to be used by the larger MS community. Without the initial prototype, many MS-based instruments today would not be produced. Additionally, biotechnology companies are the main drivers for research, development, and production of novel instruments, but the tools for prototyping instrumentation have never been more accessible. Here, we present a tutorial on prototyping instrumentation through the case study of developing the Next Generation IR-MALDESI source to show that an engineering degree is not required to design and construct a prototype instrument with modern hardware and software. We discuss the prototyping process, the necessary skills required for efficient prototyping, and information about common hardware and software used within initial prototypes.

EARLY DEVELOPMENT OF BIO-EXPERIENTIAL TECHNOLOGY TO SUPPORT PERSONS WITH DEMENTIA AND CARE PARTNERS AT HOME

Abstract Bio-experiential approaches offer an interactive, multisensory, immersive environmental experience using technology and physical design to promote mind-body wellness. These designs have the potential to provide an in-home solution to help persons living with dementia and their care-partners manage challenges including agitation, conflict, stress, and difficult emotions (e.g., grief). This presentation discusses a partnership between an interdisciplinary academic team and a creative design and technology studio that has pioneered bio-experiential designs. This partnership’s mission is to develop a free interactive, immersive bio-experiential platform that offers a positive and engaging experience for both persons living with dementia and their care-partner(s). Our team iteratively developed an initial prototype using multiple strategies rooted in user-centered design, including a literature review, design thinking workshop with the full team, and two focus groups with clinicians (N=10; neurologists, geriatric psychiatrists, geriatricians, neuropsychologists, social workers, occupational therapists). Early development emphasized safety to minimize risk of increased agitation or other neuropsychiatric symptoms (e.g., hallucinations, sleep impairments). Key recommendations to enhance safety and usability included simple calming visuals and sounds, personalized experiences, familiar stimuli, and multisensory engagement (e.g., music, tactile stimuli). Increasing accessibility was also discussed related to ease of use and availability of platforms (e.g., laptop, television). We are now preparing for “live” iterative usability testing of our prototype (i.e., beta testing) with a diverse group of persons living with dementia and care-partner(s) before efficacy testing. The larger goal is implementation and wide dissemination as well as adaptations for other neurodegenerative conditions. *Dr. Vranceanu and Ritchie are co-senior authors.

Validity and Practicality of SSCS-Based Student Worksheet on Ecology Material and Environmental Change

This research aims to produce student worksheet based on SSCS (Search, Solve, Create and Share). This type of research is development research using the Plomp model. The development stage of this model starts from the initial investigation stage, the development or prototyping stage, and the assessment stage. The instruments used in this development research were teacher questionnaire sheets, student response questionnaire sheets, self-evaluation sheets, and SSCS-based LKPD validation sheets (Search, Solve, Create and Share) by experts, as well as SSCS-based LKPD practicality assessment sheets (Search, Solve, Create and Share) which is filled in by teachers and students. The results showed that the SSCS-based LKPD (Search, Solve, Create and Share) was very valid with a score of 86.31%. The practicality assessment of student assessment in field trials (group evaluation) with a score of 92.00% with very practical criteria, and the practicality assessment by the teacher obtained a score of 96.00% with very practical criteria. It can be concluded that the LKPD based on SSCS (Search, Solve, Create and Share) that has been developed is included in the category of very valid and very practical.

Pediatric Delirium Educational Tool Development With Intensive Care Unit Clinicians and Caregivers in Canada: Focus Group Study.

Pediatric intensive care unit (PICU)-associated delirium contributes to a decline in postdischarge quality of life, with worse outcomes for individuals with delayed identification. As delirium screening rates remain low within PICUs, caregivers may be able to assist with early detection, for which they need more education, as awareness of pediatric delirium among caregivers remains limited. This study aimed to develop an educational tool for caregivers to identify potential delirium symptoms during their child's PICU stay, educate them on how to best support their child if they experience delirium, and guide them to relevant family resources. Web-based focus groups were conducted at a tertiary pediatric hospital with expected end users of the tool (ie, PICU health care professionals and caregivers of children with an expected PICU length of stay of over 48 h) to identify potential educational information for inclusion in a family resource guide and to identify strategies for effective implementation. Data were analyzed thematically to generate requirements to inform prototype development. Participants then provided critical feedback on the initial prototype, which guided the final design. In all, 24 participants (18 health care professionals and 6 caregivers) attended 7 focus groups. Participants identified five informational sections for inclusion: (1) delirium definition, (2) key features of delirium (signs and symptoms), (3) postdischarge outcomes associated with delirium, (4) tips to inform family-centered care, and (5) education or supportive resources. Participants identified seven design requirements: information should (1) be presented in an order that resembles the structure of the clinical discussion around delirium; (2) increase accessibility, recall, and preparedness by providing multiple formats; (3) aim to reduce stress by implementing positive framing; (4) minimize cognitive load to ensure adequate information processing; (5) provide supplemental electronic resources via QR codes; (6) emphasize collaboration between caregivers and the health care team; and (7) use prompting questions to act as a call to action for caregivers. Key design requirements derived from end-user feedback were established and guided the development of a novel pediatric delirium education tool. Implementing this tool into regular practice has the potential to reduce distress and assist in the early recognition and treatment of delirium in the PICU domain. Future evaluation of its clinical utility is necessary.

Co-Design of a Virtual Reality Multiplayer Adventure Game for Adolescents With Autism Spectrum Disorder: Mixed Methods Study.

Virtual reality (VR) adventure games can offer ideal technological solutions for training social skills in adolescents with autism spectrum disorder (ASD), leveraging their support for multisensory and multiplayer interactions over distance, which may lower barriers to training access and increase user motivation. However, the design of VR-based game environments for social skills training is still understudied and deserves the deployment of an inclusive design approach to ensure its acceptability by target users. We aimed to present the inclusive design process that we had followed to develop the Zentastic VR adventure game to foster social skills training in adolescents with ASD and to investigate its feasibility as a training environment for adolescents. The VR game supports multiplayer training sessions involving small groups of adolescents and their therapists, who act as facilitators. Adolescents with ASD and their therapists were involved in the design and in an explorative acceptability study of an initial prototype of the gaming environment, as well as in a later feasibility multisession evaluation of the VR game final release. The feasibility study demonstrated good acceptability of the VR game by adolescents and an enhancement of their social skills from baseline to posttraining. The findings provide preliminary evidence of the benefits that VR-based games can bring to the training of adolescents with ASD and, potentially, other neurodevelopmental disorders.

Performance of optimized prototype LUMIPULSE G immunoassays for plasma pTau181 and pTau217

AbstractBackgroundThere is a need for automated random access plasma phosphorylated Tau (pTau) methods that reflect AD pathology with consistent performance. LUMIPULSE (LP) assays could offer a solution. Initial prototype pTau181 and pTau217 LP assays showed lower clinical performance versus Quanterix Homebrew assays (Poster #79533 – P4‐06). This new study presents optimized pTau181 and pTau217 LP assays, showing data on their analytical and clinical performance compared to the initial prototype method (Ref) and an in‐house pTau181 Quanterix Homebrew assay.MethodPlasma pTau181 and pTau217 LP assays were developed using recombinant pTau181 mAb RD‐070, resp. pTau217 mAb RD‐085, combined with an ALP‐Fab conjugate from recombinant N‐terminal Tau mAb RD‐073. In the optimized automated protocol, an assay specific diluent (ASD) is added (20%) to the sample to increase signal specificity. Analytical and clinical performance of the reference versus ASD‐treated prototypes to distinguish AD from controls was evaluated using 40 CSF‐confirmed AD‐dementia and 40 age‐matched healthy volunteer plasma samples.ResultAnalytical performance: Both optimized pTau181 and pTau217 LP tests demonstrated high precision comparable to their reference assays (inter‐run %CV on 3 neat plasma samples < 7.4). LLOQ was not affected by ASD‐treatment. Clinical performance: pTau181 LP assays demonstrated comparable AUC and median fold change with (AUC 0.828, fold change 1.9) and without ASD (AUC 0.823, fold change 1.5) while the SIMOA assay demonstrated a higher AUC (0.866) and fold change (2.9). For pTau217, the performance improved from an initial AUC of 0.918 to 0.935, and a fold change of 3.72 instead of initially 2.76. (Figure 1). All assays correlated strongly (p<0.00001) (Table 1); highest correlations among them were observed with the pTau217 ASD‐treated assay.ConclusionUsing an assay specific diluent resulted in improved clinical performance for the pTau217 prototype LUMIPULSE assay, in line with other published pTau217 assays. We did not achieve improved performance of the pTau181 LP assay with the ASD addition. Most important to emphasize, a performant pTau217 assay prototype is under development on an fully automated, scalable platform. Next steps include verification of performance in additional well‐characterized AD cohorts and characterization of lot consistency and robustness of the pTau181 and pTau217 N‐terminal LUMIPULSE assays.