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Smartphone-based voice wellness index application for dysphonia screening and assessment: development and reliability /
No full textObjective This study aimed to develop a Voice Wellness Index (VWI) application combining the acoustic voice quality index (AVQI) and glottal function index (GFI) data and to evaluate its reliability in quantitative voice assessment and normal versus pathological voice differentiation. Study design Cross-sectional study. Methods A total of 135 adult participants (86 patients with voice disorders and 49 patients with normal voices) were included in this study. Five iOS and Android smartphones with the "Voice Wellness Index" app installed were used to estimate VWI. The VWI data obtained using smartphones were compared with VWI measurements computed from voice recordings collected from a reference studio microphone. The diagnostic efficacy of VWI in differentiating between normal and disordered voices was assessed using receiver operating characteristics (ROC). Results With a Cronbach's alpha of 0.972 and an ICC of 0.972 (0.964–0.979), the VWI scores of the individual smartphones demonstrated remarkable inter-smartphone agreement and reliability. The VWI data obtained from different smartphones and a studio microphone showed nearly perfect direct linear correlations (r = 0.993–0.998). Depending on the individual smartphone device used, the cutoff scores of VWI related to differentiating between normal and pathological voice groups were calculated as 5.6–6.0 with the best balance between sensitivity (94.10–95.15%) and specificity (93.68–95.72%), The diagnostic accuracy was excellent in all cases, with an area under the curve (AUC) of 0.970–0.974. Conclusion The “Voice Wellness Index” application is an accurate and reliable tool for voice quality measurement and normal versus pathological voice screening and has considerable potential to be used by healthcare professionals and patients for voice assessment
What entrepreneurial decisions enable the breeding of digital platform unicorns? /
No full textDigital platforms have revolutionized business sectors; however, despite their significant success, platform unicorns remain rare. While extensive research exists on digital platform growth, it is uncertain what entrepreneurial decisions achieve unicorn status. We address the research question of what combination of complementary entrepreneurial decisions increases and decreases the likelihood of becoming a platform unicorn. The study examines 125 digital mental health platform ventures, including 12 unicorns, using the Dealroom database and decision tree methodology. We provide combinations of complementary decisions concerning fundraising timing, funding sources, digital technologies, and business model choices that affect a platform venture's probability of becoming a unicorn. The study offers decision profiles for navigating the uncertainties of the digital age. We discuss implications for strategic entrepreneurship and a judgment‐based approach
Sustainable preservation of plant-based meat analogues using distinct conifer needle aqueous extracts /
No full textThe increasing demand for sustainable and clean-label foods has intensified the search for natural preservatives that are capable of replacing synthetic additives. In this study, an exploratory assessment of two distinct spruce needle aqueous extracts were conducted—an aqueous extract of Picea pungens (NWE-1) and an aqueous extract of Picea abies obtained after prior supercritical CO2 treatment (NWE-2)—and both were investigated as potential bioactive ingredients for plant-based meat analogues. Using UPLC–MS, both extracts were comprehensively characterized, revealing a diverse array of phenolic acids, flavonoids, and glycosides. Even though NWE-2 contained a broader range of bioactive compounds, NWE-1 exhibited superior antibacterial performance (total microbial count (TMC)—4.94 log CFU/g), effectively limiting microbial contamination and ensuring product stability for up to 16 days of storage below the typical spoilage threshold (6.0–7.0 log CFU/g). Sensory analysis indicated that the model plant-based meat analogue matrix tolerated up to 3% (w/w) inclusion of NWE-1 and 5% (w/w) inclusion of NWE-2 before significant degradation of flavor and overall acceptability occurred. By utilizing conifer needles as an underexploited side-stream biomass, this work offers an approach for the valorization of conifer needle material through combined green extraction and food application, contributing to circular and resource-efficient processing concepts. The study provides an exploratory perspective on the potential role of forest-derived resources in the development of natural preservatives and their possible contribution to more sustainable food preservation strategies within a circular bioeconomy framework
Heterogeneity in students’ perceptions of teaching quality: a marker of adaptive teaching? /
No full textBackground Students attending the same class can vary greatly in their perceptions of the teaching quality of the same lessons with the same teacher; however, the current understanding of heterogeneity in students’ perceptions of teaching quality, its sources, and implications remains limited. Aims This study investigated whether heterogeneity in students' perceptions of teaching quality within classes may indicate that the teacher's instruction is not equally adaptive for all students. Sample We used longitudinal data from the TALIS Global Teaching InSights study (N = 19,659 students, N = 679 mathematics teachers, across eight countries). Methods We ran multigroup latent change score models to examine the effect of student-reported adaptive teaching on (a) teaching quality ratings (clarity of instruction, autonomy support, student-teacher relationships, cognitive engagement, support for learning, support for competence, and classroom disruptions) and, importantly, (b) heterogeneity in students’ perceptions of these dimensions. Results Our findings revealed that adaptive teaching predicted lower heterogeneity in students’ perceptions—particularly regarding autonomy support, clarity of instruction, and, to some extent, support for learning, support for competence, and student–teacher relationships. Adaptive teaching was related to less classroom disruptions and more heterogeneous perceptions of disruptions within classes. Conclusions Our findings indicate that adaptive teaching can explain the extent of heterogeneity in students’ perceptions of several teaching quality dimensions. This underscores the substantive value of considering heterogeneity in student perceptions as a meaningful construct
Tikslumo vertinimas skaitmeninėje odontologijoje: intraoralinių skenerių ir papildytos realybės panaudojimas.
No full textCurrently, the surface quality of scans generated by intraoral scanners is typically evaluated using best-fit global alignment techniques, most commonly iterative closest point (ICP) algorithms. However, these methods often encounter difficulties when dealing with the complex morphology of individual dental surfaces, thereby limiting the reliability of accuracy assessments in clinical research. Meanwhile, augmented reality (AR) headsets—particularly Microsoft HoloLens 2—have been successfully implemented in various medical fields, yet their application in dentistry, especially in implantology, remains insufficiently explored, notably in terms of accuracy. Evaluating the performance of the HoloLens 2 in computer-guided dynamic navigation systems is crucial, as even minimal deviations can substantially affect procedural precision and, consequently, treatment outcomes. In this doctoral thesis, a set of guidelines was developed for the comprehensive accuracy assessment of intraoral scanners. The proposed framework encompasses reference object creation, scanning procedures, and reverse engineering techniques to analyze surface deviations and structural discrepancies. This workflow effectively differentiates the scan quality of intraoral and laboratory scanner systems, revealing distinct accuracy levels across various surface types. Additionally, the potential of augmented reality for dynamic navigation systems was examined using a reference-free evaluation approach. While integration proved feasible, accuracy deviations exceeding 1 mm in registration and visual perception restrict its clinical applicability for implant placement procedures, thereby limiting its practical utility
Phosphogypsum additive as shrinkage-reducing agent in ordinary portland cement-based mortar /
No full textPhosphogypsum, a by-product of phosphate fertilizer production, has shown promising potential as a shrinkage-reducing additive in ordinary Portland cement-based mortar. The incorporation of low PG dosages (≤6%) enhances early hydration, slightly increases the hydration peak temperature, and promotes the formation of additional ettringite and bound-water-rich hydrates, contributing to improved early performance. PG also substantially reduces drying shrinkage—from 0.0397 mm/m (reference) to −0.1600 mm/m at 15% PG—through ettringite-induced expansion and pore refinement, demonstrating its effectiveness as a shrinkage-reducing agent. Thermal analysis (XRD/TG–DTA) confirms that PG modifies hydration chemistry by increasing low-temperature dehydration while reducing portlandite and carbonate phase formation due to clinker dilution. As a result, Ca(OH)2 content decreases from 11.89 wt% for the reference mix to 8.55 wt% at 15% PG. However, higher PG levels (>9%) negatively affect strength: at 15% PG, flexural and compressive strength decrease by 38% and 47%, respectively, due to clinker dilution, excess ettringite, and unreacted gypsum. All compositions maintained durability levels corresponding to roughly 300–450 freeze–thaw cycles. Overall, PG effectively reduces shrinkage and alters hydration behavior while offering environmental benefits through industrial waste valorization. Nevertheless, high replacement levels compromise mechanical performance, underscoring the importance of optimizing PG dosage to balance shrinkage control, strength, and sustainability
Debt thresholds and unemployment nexus: a study on fiscal–monetary policy interactions across the EU member states /
No full textThis study examines the regime-dependent threshold between fiscal and monetary policy interactions across the EU-27 states, utilizing quarterly data from 2000 to 2025. A fixed-effects panel threshold regression model has been adopted in this study, using endogenously determined debt thresholds, to assess how budget, debt, money supply, inflation, and fluctuations in interest rates interact under different debt regimes. This analysis also incorporates shock dummy variables following mild recessions and inflationary pressures, the global financial crisis, the sovereign debt crisis, the COVID-19 pandemic, and recent energy price and inflationary shocks. Consequently, three major findings emerge: firstly, fiscal deficits increase unemployment across both regimes, but their positive contribution is significantly reduced by 81% in high-debt regimes. Therefore, conventional Ricardian equivalence has been supported throughout this study in terms of precautionary savings and crowding-out impacts, which further contribute to intensifying with alternative debt regimes. Secondly, monetary variables, in this paper, have demonstrated limited direct effects on unemployment mitigation that highlight the transmission mechanisms under high-debt regimes. Thirdly, the effectiveness of crisis response critically depends on existing fiscal spaces, while the debt regime is interconnected with labor market outcomes. The main findings of the study provide empirical support for the Maastricht debt criterion of 60% as a structural threshold, which is a benchmark for a fundamental shift in the policy transmission mechanism. This study has identified rules and regulations for uniform fiscal consolidation as insufficient; rather, state-contingent governance frameworks have been highly recommended for managing asymmetrical fiscal–monetary policy interactions across different debt regimes. Furthermore, it contributes to the reformation of the more impactful fiscal and monetary policy interaction rule under a monetary union
Advancing geothermal energy recovery through reactive transport modelling and horizontal well analysis: a case study of Lithuanian reservoirs /
No full textThe study underpins the geothermal energy potential of Cambrian reservoirs in Lithuania, which utilizes the use of reactive transport modelling to examine how different reinjection temperatures and flow rates affect mineral changes. The results are then applied to design field development plans, using petroleum engineering methods such as horizontal wells and induced fracturing. The research study indicates that there are some changes in porosity and permeability over time due to mineral dissolution and precipitation because of injection rates, but no adverse effect of re-injection temperature was observed. Hence, a reinjection temperature of 40 °C is geochemically stable and suitable for long-term operation, with no significant effect on mineral behavior. Moreover, application of horizontal wells proves that there is a significant increase in water production and power (thermal) output due to improved reservoir exposure. Hydraulic fracturing further enhanced the performance and flow rates, concluding that, among all the sites studied, Nausodis demonstrated the highest thermal output, while Genciai showed the lowest potential due to limited reservoir temperature and productivity. Thus, research aims to improve power output by studying how well design, reinjection methods, and chemical reactions affect the reservoir, and it shows that using horizontal wells, fracturing, and proper reinjection temperature can help increase geothermal energy recovery in Lithuania
Sustainable polyhydroxyalkanoates in the bioeconomy: a review of recent advances in production innovations, economic feasibility, and patents landscape /
No full textIn light of the global environmental crisis caused by traditional plastics and their pollution, there is an urgent need for sustainable alternatives to plastics derived from fossil fuels. Polyhydroxyalkanoates (PHA) is a microbial intracellular energy reserve with the potential to replace petroleum-based plastics and reduce environmental pollution. PHA exhibits mechanical and thermal properties comparable to petroplastics, with the added advantages of biodegradability and biocompatibility. Furthermore, their physicochemical versatility makes them suitable for a wide range of applications, including eco-friendly packaging, agricultural mulch films, and innovative medical devices. However, large-scale PHA adoption remains constrained by production costs, as well as by challenges in scalability, feedstock supply, and downstream extraction, which all culminate in an uncompetitive minimum selling price (MSP) estimated at $4-8/kg. Considering the aforementioned, this review aimed to provide a comprehensive evaluation of strategies for enhancing PHA production efficiency within a circular bioeconomy framework. It examines intrinsically diverse microbial communities that produce PHA, fermentation strategies, feedstock diversification, and green recovery techniques. It also evaluated emerging application trends and industrial potential, focusing on more than 20 PHA-related patents filed between 2020 and 2025. Finally, this study examined the economic feasibility of PHA production and identified feasible pathways toward more cost-competitive adoption of the biopolymer