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Faster-Than-Nyquist Signaling for Next-Generation Wireless: Principles, Applications, and Challenges
No full textFuture wireless networks are expected to deliver ultra-high throughput for supporting emerging applications. In such scenarios, conventional Nyquist signaling may falter. As a remedy, faster-than-Nyquist (FTN) signaling facilitates the transmission of more symbols than Nyquist signaling without expanding the time-frequency resources. We provide an accessible and structured introduction to FTN signaling, covering its core principles, theoretical foundations, unique advantages, open facets, and its road map. Specifically, we present promising coded FTN results and highlight its compelling advantages in integrated sensing and communications (ISAC), an increasingly critical function in future networks. We conclude with a discussion of open research challenges and promising directions
Exploring the intersection between collective and hierarchical leadership in online team meetings in Turkey
No full textComparison of Mathematical Modeling Approaches for Hot Air Drying and Photovoltaic/Thermal Assisted Heat Pump (PV/T-HP) Dryer Systems in Drying Capia Red Pepper (Capsicum annuum L. cv. Capia) Wastes
No full textLarge amounts of capia red pepper (Capsicum annuum L. cv. Capia) by-products, including stems, placenta, and seeds, are generated during food processing and often discarded despite their rich bioactive content. Drying process can be used to preserve food waste for longer periods by removing moisture as quickly as possible. Photovoltaic/thermal assisted heat pump (PV/T-HP) systems can be used to dry food waste in the shortest time and with low energy consumption. This study compares hot air drying and photovoltaic/thermal-assisted heat pump (PV/T-HP) systems for drying these residues, with a focus on mathematical modeling and quality preservation. Drying experiments were first conducted at 40°C, 50°C, 60°C, and 70°C using a hot air dryer to determine the optimal temperature, which was then applied in the PV/T-HP system (50°C). Five drying models were evaluated, with the Midilli and Kucuk model showing the best performance for both systems (R2: 0.99). PV/T-HP drying better preserved antioxidant activity (stems: 29.049 μM TEAC; seeds: 3.052; placenta: 15.381) and total phenolic content (stems: 200.37 mg GAE/100 g DW; seeds: 6.85; placenta: 38.21) compared to hot air drying. It also minimized color degradation, enhancing visual quality. These results highlight PV/T-HP drying as an energy-efficient, sustainable method for converting pepper waste into value-added ingredients, with reliable modeling supporting process optimization
An Inquiry into Intercultural Competence, Its Assessment and Enhancement: An Interview with Dr. Darla Deardorff
No full textUse of polysaccharide-based aerogels in iced tea clarification process
No full textPolysaccharide-based aerogels, particularly those produced from chitosan and xanthan gum, offer a sustainable and efficient alternative for clarifying ready-to-drink (RTD) tea infusions. In this study, the aerogels were applied to black and green teas to reduce turbidity and tea cream formation during 20 days of storage. Key quality attributes were evaluated, including clarity (transmittance, tea cream), color (L∗, a∗, b∗, ΔE), and catechin content. Water mobility assessed by NMR relaxation and diffusion, molecular interactions with tea components examined by FTIR. Chitosan aerogels significantly reduced cream formation and helped maintain color stability in black tea. In green tea, however, they caused more noticeable color changes, reflected by higher ΔE values, though catechin losses remained moderate. FTIR results showed surface-level interactions between aerogels and tea components such as proteins and polyphenols. NMR relaxometry also indicated reduced water mobility after treatment, supporting surface adsorption. Xanthan gum aerogels produced similar clarity improvements, although color shifts were slightly more pronounced in green tea. Despite these effects, both aerogels preserved essential quality characteristics. Overall, food-grade polysaccharide aerogels serve as effective alternatives to conventional adsorbents. Their porous structure allows selective removal of turbidity-related compounds, while their easy handling and biodegradability make them promising options for beverage clarification
Understanding the relationship between locus of control and pedestrian behaviors: moderating effects of personality
No full textRecent statistics on pedestrian safety in public traffic underline the vulnerability of pedestrians in urban traffic settings. Few studies have investigated the influences of individual difference variables on pedestrian behaviors, and no prior study explored these behaviors in relation to locus of control. The present study is the first one exploring the relations that prevail between locus of control, personality traits and pedestrian behaviors. It adopts a multidimensional approach to locus of control considering it as an individual difference variable. Participants (n = 250; MAGE = 25.33 [SD = 9.92]; 66% female) were asked to fill out questionnaires on locus of control, personality traits and pedestrian behaviors. The data were analyzed using correlation matrix analysis and moderation analysis in Jamovi. The results of the moderation analyses indicate that in addition to main effects, several interaction effects were present in the set of moderations including chance as the predictor variable. Specifically, at average and high (but not low) levels of agreeableness, as the perception of chance controlling the events increased, aggressive violations also increased. Also, at average and high levels of both conscientiousness and agreeableness, the relationship between chance locus and positive behaviors was non-significant. However, at low levels of these personality traits, increase in the perception of chance controlling the events was associated with decreased positive behaviors. Significant interaction terms highlight the importance of personality traits in influencing the degree of relationship between locus of control and pedestrian behaviors
EnSCAN: ENsemble Scoring for prioritizing CAusative variaNts across multiplatform GWASs for late-onset alzheimer's disease
No full textLate-onset Alzheimer's disease (LOAD) is a progressive and complex neurodegenerative disorder of the aging population. LOAD is characterized by cognitive decline, such as deterioration of memory, loss of intellectual abilities, and other cognitive domains resulting from due to traumatic brain injuries. Alzheimer's Disease (AD) presents a complex genetic etiology that is still unclear, which limits its early or differential diagnosis. The Genome-Wide Association Studies (GWAS) enable the exploration of individual variants' statistical interactions at candidate loci, but univariate analysis overlooks interactions between variants. Machine learning (ML) algorithms can capture hidden, novel, and significant patterns while considering nonlinear interactions between variants to understand the genetic predisposition for complex genetic disorders. When working on different platforms, majority voting cannot be applied because the attributes differ. Hence, a new post-ML ensemble approach was developed to select significant SNVs via multiple genotyping platforms. We proposed the EnSCAN framework using a new algorithm to ensemble selected variants even from different platforms to prioritize candidate causative loci, which consequently helps improve ML results by combining the prior information captured from each dataset. The proposed ensemble algorithm utilizes the chromosomal locations of SNVs by mapping to cytogenetic bands, along with the proximities between pairs and multimodel Random Forest (RF) validations to prioritize SNVs and candidate causative genes for LOAD. The scoring method is scalable and can be applied to any multiplatform genotyping study. We present how the proposed EnSCAN scoring algorithm prioritizes candidate causative variants related to LOAD among three GWAS datasets
Bond-based peridynamic fatigue analysis of ductile materials with Neuber’s plasticity correction
No full textThis study introduces an approach for performing bond-based (BB) peridynamic (PD) fatigue analysis of ductile materials. Existing BB PD fatigue models do not account for the effect of plastic deformation. The current approach addresses this by incorporating Neuber’s plasticity correction concept into the fatigue model. Neuber’s correction adjusts the stress and strain predictions of the PD elastic solution to account for local plastic deformation around crack tips. The PD fatigue simulations demonstrate the effectiveness of this method and improvements in fatigue life predictions by considering local plasticity effects. The numerical results first examine the response of a ductile plate without a crack under quasi-static monotonic loading. Subsequently, specimens exhibiting Mode I and mixed-mode crack propagation paths due to cyclic loading are analyzed. The PD predictions accurately capture the test data. Additionally, the model specifically investigates the effect of a stop hole on fatigue life
Reflective problem posing instructions for preservice mathematics teachers to elicit characteristics of the modelling problems: context vis-a-vis content
No full textThis study portrays the qualitative potential of three iterative reflective problem posing instructions for preservice teachers to elicit the characteristics of mathematical modelling problems. The instructions are characterised by a problem posing prompt and different forms of reflective practices, reflection-on-action, reflection-in-action, and reflection on reflection-in-action. Each instruction was administered to a distinct cohort of 24 preservice mathematics teachers who worked in pairs to pose a modelling problem and provided a written reflection. A total of 36 modelling problems and associated reflections were analysed through content and thematic analysis. While content analysis was held separately for each instruction to elicit the task characteristics, thematic analysis compared these three sets of content analysis to reveal patterns that denote the potential role of the different forms of reflection for incorporating the task characteristics into modelling problems. The findings indicated an aptitude for the context to be a medium for developing mathematical insight, relying on the context-content balance and open-endedness nature of the modelling problems. Furthermore, preservice teachers' reflective articulation addressed the sources of openness (i.e., multiplicity of solution methods, acceptable answers, assumptions, and realistic considerations) and ways operating with the open-ended nature of the modelling problems. Hence, reflective problem posing instructions demonstrated a form of educational support for posing modelling problems, the implications of which are further discussed
