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Recent Submissions

Hot-water immersion enhances vertical-jump performance, lower-limb power, and stretch-shortening cycle
(Human Kinetics, 2025-09-16) Rodrigues, Patrick; Lawley, JS; Zovilé, GCF; Jaén-Carrillo, D
Purpose: This study aimed to (a) examine the effects of hot-water immersion (HWI) on vertical-jump performance, lower-limb power, and stretch-shortening cycle responses and (b) evaluate temperature-dependent responses by comparing 2 HWI conditions (40 °C vs 42 °C). Methods: Twenty healthy, physically active participants (12 male and 8 female; age 25.1 (2.7) y; body mass index 22.6 [1.1] kg/m²) completed countermovement-jump (CMJ) and drop-jump assessments before, after, and 15 minutes after a 45-minute water-immersion session at either 34 °C (control), 40 °C, or 42 °C in a randomized order. CMJ outcomes included jump height, peak force, and peak power, while drop-jump outcomes included jump height, reactive strength index, and vertical stiffness. Results: CMJ height increased following a 45-minute HWI session at both 40 °C and 42 °C (P < .001, d = 1.09; P < .001, d = 1.77), with no differences between the 2 conditions (P = .515). Similar improvements were found for peak power and force. At 15 minutes post–water immersion, all performance measures returned to baseline and did not differ from the control condition. For the drop-jump tests, a main effect of temperature was observed. HWI at 42 °C significantly increased drop-jump height (P = .004; d = 0.71), whereas 40 °C did not (P = .205). Reactive strength index increased following both 40 °C (P = .002; d = 0.74) and 42 °C (P < .001; d = 0.91) conditions. No significant changes were observed in vertical stiffness. Conclusion: Both HWI conditions, 40 °C and 42 °C, improved CMJ performance (height, force, and power) and reactive strength index, while only HWI at 42 °C enhanced drop-jump height. These effects were transient, returning to baseline within 15 minutes postimmersion.
Providing access to socially mediated reinforcement in AOD treatment: Effects on recovery-oriented behaviour in community alcohol and other drug treatment
(The University of Waikato, 2026) MacLean, Morgan; Blackmore, Tania
Reinforcement-based interventions are effective in AOD treatment, but many rely on resource-intensive procedures or abstinence-based contingencies. This study examined whether increasing access to clinician-delivered socially mediated reinforcement (SMR) between counselling sessions was associated with behaviour consistent with recovery within a community AOD service. A non-concurrent multiple-baseline-across-participants design was used with five taiohi ages 18 to 23 years receiving community AOD counselling in Aotearoa NZ. Participants received one personalised, noncontingent supportive message each week during the intervention phase. Recovery goal engagement was the primary outcome, with session attendance and ADOM scores examined as secondary measures. Visual data analysis did not demonstrate a functional relationship between SMR and the outcome measures. However, some participants showed increases in recovery progress, goal engagement, and treatment attendance that were maintained across treatment. Participant disengagement and missing data limited the interpretation of results. Findings support further investigation of SMR within community AOD settings.
Effects of different triggering mechanisms on pulse shaping of a TMS pulse generator based on supercapacitor energy storage
(IEEE, 2025) Raju, Soniya; Kularatna, Nihal; Wilson, Marcus T.; Steyn-Ross, D. Alistair
High-voltage pulse generators are useful in many applications such as transient surge simulators, electric fence energizers, and transcranial magnetic stimulation (TMS) systems. Traditionally they are based on a high-voltage DC power supply with or without voltage multipliers for raising the voltage to several thousand volts. In contrast to these complex and costly approaches, we use a pre-charged supercapacitor followed by a step-up transformer and associated output circuitry to develop an inexpensive and flexible high-voltage pulse generator for applications in transcranial magnetic stimulation. Our new approach is to use the high-power delivery capability of commercial supercapacitors. In this work, we explore the advantages of different waveforms applied to the MOSFET associated with the secondary stage of the circuit topology and how they affect the final pulse shape.
Identifying biological fluids using hyperspectral near-infrared imaging and machine learning for forensics analysis
(IEEE, 2025) Faisal, Shah; Ooi, Melanie Po-Leen; Kuang, Ye Chow; Thawdar, Yaminn; Abeysekera, Sanush K.; Reutemann, Peter; Fletcher, Dale; Fleming, Rachel; McClelland, Heather
Near-infrared hyperspectral imaging captures subtle spatial and spectral characteristics of biological fluids on fabrics for forensics analysis. It is a non-destructive approach that could potentially be used for onsite crime scene investigations. However, current data processing methods lack the accuracy and sensitivity required for real-world applications. This paper utilised a 900-1700nm hyperspectral camera to capture blood, semen, and urine fluids that were systematically applied onto a patterned rayon fabric. Multi-Later Perception (MLP) and 1D Convolutional Neural Network (1D-CNN) classifiers were then trained to identify them. A dual evaluation approach, combining machine learning model evaluation metrics (F1-score and accuracy) with uncertainty quantification (Entropy-based and Modal Predictionbased) was then used to assess the performance of the classifiers. The results indicated that the MLP slightly outperformed the 1DCNN for fluid-specific classification tasks, achieving slightly better accuracy and F1-score and lower uncertainty in predictions.
Supercapacitor based TMS pulse generator design - Experimental results versus Matlab MOSFET simulation model
(IEEE, 2025) Raju, Soniya; Kularatna, Nihal; Wilson, Marcus T.; Steyn-Ross, D. Alistair
Supercapacitors are ideal for short-term energy storage due to their high instantaneous power capability. Unlike traditional high-voltage DC power supplies typically used in transcranial magnetic stimulation (TMS) applications, a precharged supercapacitor module can serve as a cost-effective alternative for building a pulse generator with adjustable waveform capabilities. This approach utilizes a supercapacitor module with a capacitor bank rated at a few hundred farads and 10 V, combined with a step-up transformer-based converter and medium-voltage MOSFETs to meet TMS requirements. The output of this pulse generator, including the effects of varying gate voltages, can be accurately predicted using a robust model. This paper presents the design of a MOSFET model, incorporating a newly derived equation that effectively captures the subthreshold, near-threshold, and above-threshold regions of the MOSFET operation. Experimental results are provided and compared with Matlab model simulations, demonstrating the model's accuracy and effectiveness.