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Electrochemical depolymerization of lignin catalyzed by biomass-based magnetic-electrocatalyst
(2026) Chi, Jingzhi; Kang, Kang; Fatehi, Peadram
The depletion of fossil resources has intensified the search for sustainable carbon feedstocks, placing lignin, the most abundant renewable aromatic macromolecule in nature, at the center of modern biorefineries and circular bioeconomy strategies. Despite its enormous potential, lignin valorization remains challenging because its highly cross-linked three-dimensional architecture and exceptional chemical stability hinder efficient depolymerization and selective conversion. Electrochemical oxidation has emerged as an attractive alternative to conventional thermochemical approaches by operating under mild conditions without requiring strong chemical oxidants. Nevertheless, practical implementation remains constrained by two persistent challenges: heterogeneous powder catalysts are difficult to separate from reaction media after electrolysis, while inefficient mass transfer at the solid–liquid interface limits catalytic performance. To address these limitations, this thesis develops a novel strategy in which waste maple wood (MW) and the metal-rich industrial residue red mud (RM) are co-pyrolyzed to produce a low-cost magnetic biochar (MBC) heterogeneous electrocatalyst. Systematic optimization of the synthesis conditions identified M-MBC–5/1–900, prepared at 900 °C with a MW-to-RM mass ratio of 5 : 1, as the most active catalyst. During high-temperature carbothermic reduction, the iron oxides originally present in RM are transformed in situ into highly active zero-valent iron (α-Fe0) and iron carbide (Fe3C) nanophases, which become uniformly embedded within a highly graphitized carbon framework possessing a hierarchical mesoporous architecture. At the same time, the silica network derived from the intrinsic Si–O species in RM provides robust structural support, effectively suppressing nanoparticle sintering and agglomeration throughout pyrolysis. The resulting catalyst combines abundant accessible active sites with excellent structural stability, features that were consistently reflected in its superior electrochemical performance during repeated experiments. To account for the remarkable catalytic activity observed in alkaline electrolytes, experimental evidence directs our attention to the interfacial characteristics of MBC. The graphitized carbon matrix is proposed to establish strong π–π stacking and hydrophobic interactions with the aromatic backbone of lignin, overcoming electrostatic repulsion and promoting efficient enrichment of lignin molecules at the catalyst surface. Once concentrated at the electrochemical interface, lignin appears to undergo a distinctly time-dependent oxidation pathway likely dominated by reactive oxygen species, particularly hydroxyl radicals (·OH). During the initial 0–2 h of electrolysis, selective depolymerization is inferred to preferentially cleave the susceptible β–O–4 aryl ether bonds and Cα–Cβ linkages, fragmenting the polymeric backbone into value-added aromatic compounds, including vanillin, together with a limited amount of acetate. Extending the electrolysis period to 4–6 h fundamentally changes the reaction trajectory. The accumulated intermediates are deduced to undergo extensive over-oxidation, during which irreversible ring-opening (de-aromatization) reactions likely convert aromatic monomers into low-molecular-weight organic acids (LMWOAs), including formate, acetate, and various dicarboxylic acids. This progressive transformation is strongly supported by gel permeation chromatography (GPC), whose refractive index (RI) profiles reveal continuous fragmentation of the lignin macromolecular network. After 6 h of electrolysis, the Mw decreases dramatically from 2759 to 530 g mol–1, corresponding to an 80.8% reduction and providing compelling evidence for the highly efficient degradation of lignin. These findings collectively demonstrate that MBC electrocatalytic system offers advantages extending well beyond catalytic activity alone. The co-pyrolysis strategy lowers the specific energy requirement for catalyst synthesis by more than 50%, while electrolysis conducted under ambient conditions at an optimized lignin concentration of 5 g L–1 further reduces the overall energy demand of the conversion process. Equally significant is the incorporation of in situ generated magnetic nanophases, which impart excellent room-temperature magnetic responsiveness and enable rapid separation of the catalyst from the reaction mixture using only an external magnetic field. By simultaneously addressing catalyst recovery, mass-transfer limitations, and catalytic efficiency, this work establishes an integrated and economically viable platform for electrochemical lignin valorization. The proposed MBC catalyst therefore provides both fundamental mechanistic insights and practical technological support for advancing the sustainable and industrial-scale utilization of lignin within future circular biorefineries.
Influence of menthol nasal inhalation on self-paced cycling time-trial performance, perceptual and physiological responses in active adult males and females
(2026) Mayer, Tyson J.; Kivi, Derek; Henderson, Zachariah; Klarner, Taryn; Sinden, Kathryn
Menthol has been investigated as a perceptual ergogenic aid because it produces a cooling sensation without directly reducing core or skin temperature. However, nasal inhalation remains underexplored during self-paced endurance exercise, particularly in studies examining sex-based differences. This study examined the effects of repeated menthol nasal inhalation and sex on performance, perceptual, and physiological responses during self-paced cycling in physically active adults. Forty participants (20 males and 20 females) completed a pseudo-randomized, counterbalanced study consisting of a familiarization session and two experimental trials: menthol and control. During each trial, participants completed a 15-minute self-paced cycling time trial at an individualized resistance. Menthol vapour or air was administered nasally for 5 seconds at 0, 5, and 10 minutes. Performance outcomes included total distance and distance normalized to body mass. Perceptual outcomes included ratings of perceived exertion (RPE), thermal sensation (TS), and respiratory comfort (RC), while the physiological outcome was heart rate (HR). RPE, TS, RC, and HR were averaged across the 5-, 10-, and 15-minute time points. Performance and HR were analysed using 2 × 2 mixed-design ANOVAs, whereas RPE, TS, and RC were analysed using Wilcoxon signed-rank tests, with Mann–Whitney U tests used to compare condition-related changes between sexes. Participants covered a greater total distance during menthol than control, F(1, 38) = 7.65, p = .009, ηp² = .168, and achieved a greater normalized distance, F(1, 38) = 7.63, p = .009, ηp² = .167. Significant Condition × Sex interactions indicated larger performance improvements among females. Within the perceptual domain, RPE did not differ significantly between conditions (p = .054), whereas TS (p = .029) and RC (p = .041) were significantly lower during menthol, indicating cooler thermal sensations and less respiratory discomfort. Condition-related changes in TS (p = .039) and RC (p = .024) differed significantly between sexes, with larger responses among females. Within the physiological domain, mean HR was significantly higher during menthol (p = .016), with no significant Condition × Sex interaction. These findings indicate that repeated menthol nasal inhalation influences performance, perceptual, and physiological responses during self-paced cycling, with sex contributing to the magnitude of selected performance and perceptual responses.
The effect of kinesiology tape on countermovement jump performance in recreationally active and varsity volleyball females
(2026) Bosinger, Brandon; Kivi, Derek; Przysucha, Eryk; Read, Taryn Klarner
Context: The countermovement jump (CMJ) is commonly used to assess lower-extremity explosive performance and stretch-shortening cycle (SSC)-related force-time characteristics in volleyball athletes. Although kinesiology tape (KT) has been proposed to influence muscle function through mechanical and sensory effects, research examining its influence on vertical jump performance has produced inconsistent findings. Most previous jumping studies have also focused on jump height or isolated kinetic measures, while the effects of KT applied specifically to the superficial quadriceps on phase-specific CMJ mechanics remain unclear. Objective: To examine the effects of acute bilateral KT application to the superficial quadriceps on vertical power and CMJ performance assessed through phase-specific kinetic, kinematic, and temporal characteristics between recreationally active females and competitive female volleyball athletes. Design: Two-group, pre-test post-test mixed design. Method: Twenty-four females participated, including 12 recreationally active participants (21.8 ± 2.0 years) and 12 competitive volleyball athletes (19.9 ± 2.0 years). KT was applied bilaterally to the rectus femoris, vastus lateralis, and vastus medialis with approximately 25% stretch. Participants completed three maximal-effort CMJs under no-tape and KT conditions, with condition order randomized and counterbalanced within each group. Vertical ground reaction force was recorded at 1000 Hz using an Advanced Mechanical Technology, Inc. force platform and processed using MATLAB. Dependent variables included jump height, reactive strength index (RSI), peak unweighting velocity, countermovement depth, braking rate of force development (RFD), vertical ground reaction force (vGRF) at zero velocity, peak propulsion power, total time to take-off, and unweighting, braking, and propulsion phase times. Separate 2 x 2 mixed ANOVAs were conducted for each dependent variable, with follow-up simple effects tests performed when significant interactions were identified. Statistical significance was established at α = .05. Results: No significant main effect of taping condition was identified for jump height, RSI, peak propulsion power, braking RFD, vGRF at zero velocity, peak unweighting velocity, countermovement depth, total time to take-off, braking time, or propulsion time. Peak propulsion power demonstrated a significant main effect of group (F(1,22) = 7.76, p < .05, η² = .26), with the competitive volleyball group producing greater values than the recreationally active group regardless of taping condition. Unweighting phase time demonstrated a significant Group x Taping Condition interaction (F(1,22) = 7.41, p < .05, ηp² = .25). Follow-up analysis indicated that mean unweighting time decreased from 0.61 s in the no-tape condition to 0.56 s with KT in the competitive volleyball group (t(11) = 2.97, p < .05, d = .86), whereas no significant change occurred in the recreationally active group. The reduction in unweighting time was not accompanied by improvements in subsequent kinetic variables, jump height, or RSI. Conclusions: Acute bilateral KT applied to the superficial quadriceps with 25% stretch did not provide evidence of improved CMJ performance or the measured phase-specific force-time characteristics in recreationally active females or competitive female volleyball athletes. Although KT reduced unweighting time in the competitive volleyball group, the isolated temporal change was not accompanied by enhanced kinetic output or jump performance. Competitive volleyball athletes demonstrated greater peak propulsion power than recreationally active females, but this difference did not correspond with significantly greater jump height or RSI. These findings are specific to the acute quadriceps KT application and stretch magnitude examined.
Trauma, ableism, and the CODA experience in educational contexts
(2026) McLetchie, Ashley; Mastrangelo, Sonia; Narine, Caroline; Lovell-Johnston, Meridith; Snodden, Kristin
This qualitative phenomenological study explored how ableist societal structures influence the identity development, lived experiences, and well-being of Children of Deaf Adults (CODA), with particular attention to educational contexts. Guided by Critical Disability Theory and Stuart Shanker’s Self-Regulation Framework, the study examined how systemic barriers contribute to both hardship and resilience among CODAs and how educational systems can better recognize and support them. Eight adult CODAs between the ages of 20 and 34 participated in semi-structured interviews and completed a demographic questionnaire. This study contributes to the limited body of research on CODAs by centering their voices and lived experiences. It recommends recognizing CODAs as Multiple Language Learners (MLLs), improving educator knowledge of Deaf culture and bilingual language development, ensuring accessible communication for Deaf parents, increasing Deaf and CODA representation within curricula, and expanding culturally responsive mental health supports. Ultimately, the findings call for educational and social systems that move beyond accommodation toward equity, cultural validation, and meaningful inclusion for CODAs and their families.
A comparative structural workflow for investigating structural features associated with immunoglobulin E cross-reactivity between cow’s milk and respiratory lipocalin allergens
(2026) Peter, Ikebek S.; Floriano, Wely; Dayer, Guillem; Oba, Gabriel; Rafferty, Steven
Background: Cow’s milk allergy and allergic asthma can occur in the same individuals, but it is not well understood at the molecular level. Bovine β-lactoglobulin (Bos d 5) is a major cow’s milk allergen and a member of the lipocalin protein family. Several clinically important respiratory allergens are lipocalins. Their shared fold provides a basis for comparing surfaces that may be relevant to IgE recognition. Objective: To develop a structural workflow for comparing Bos d 5 IgE-binding regions with corresponding regions in milk, respiratory and human lipocalins. Methods: Literature-reported linear IgE-binding regions of Bos d 5 and the conformational epitope defined from the Bos d 5 IgE–Fab complex were mapped onto homologous lipocalin structures using structural alignment. In parallel, comparative Fab–query allergen models were generated by positioning each query structure in the binding orientation defined by the Bos d 5 IgE–Fab complex. Structural and physicochemical descriptors were calculated after standardized preparation without additional energy minimization (RAW) and with minimization (MIN). Similarity to Bos d 5 was assessed using principal component analysis (PCA), Euclidean distance-based ranking, and group comparisons using permutation tests. Results: The dataset comprised the Bos d 5 reference structure (n = 1), respiratory allergens (n = 23), human lipocalins (n = 18), and β-lactoglobulin (βLG) homologs (n = 17 Across mapped linear IgE-binding regions, non-bovine ruminant βLGs most frequently ranked closest to Bos d 5, occupying the top rank in 8 of 12 analyses under the RAW protocol and 7 of 12 analyses under the MIN protocol. For the mapped conformational epitope region, non-bovine ruminant βLGs showed the smallest median distance to Bos d 5 under both protocols (RAW: 0.82; MIN: 1.10). The comparison with respiratory allergens was significant under RAW (p = 0.0311), but not under MIN (p = 0.0774). In the MIN composite analysis, median distances were 1.60 for non-bovine ruminant β-lactoglobulins, 4.46 for respiratory allergens and 4.51 for human lipocalins. Several respiratory lipocalins, including Fel d 4, Can f 4, Mus m 1, Fel d 7, and Cav p 1, repeatedly appeared among nearer neighbors in selected descriptor sets; however, this pattern was not consistent across all descriptor sets. Conclusion: This study developed a reproducible structural comparison workflow for evaluating IgE-binding surface similarity across homologous lipocalins. Application to Bos d 5 consistently recovered close similarity among non-bovine ruminant βLGs, as expected from their close evolutionary and structural relationship. A subset of respiratory lipocalins showed partial structural similarity in selected analyses, but this pattern was not consistent across all comparisons. The workflow therefore provides a way to prioritize candidate proteins and surface regions for experimental testing of IgE binding and possible cross-reactivity.