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Comprehensive evaluation of battery cooling mechanisms including two-phase immersion with 3M™ NOVEC™-7000 and 7100
Get PDFEffective thermal management is critical for ensuring the safety, performance, and lifespan of lithium-ion batteries (LIBs), particularly in high-demand applications such as electric vehicles. This study presents a comparative experimental evaluation of five battery thermal management strategies—natural and forced air convection, cold plate cooling, and single-phase (3M™ NOVEC™ 7100) and two-phase (3 M™ NOVEC™ 7000) immersion cooling, each tested without and with porous structures to enhance coolant distribution and boiling behaviour. A distinguishing feature of this work is the use of a realistic 24-cell (12S2P) battery pack, significantly larger than typical laboratory-scale tests, enabling a more practical assessment of intra-pack thermal gradients. Temperatures were recorded from seven spatially distributed locations to capture nonuniformities within the pack during operation. A key innovation is the integration of porous compression pads within immersion-cooled configurations. These structures enhance fluid transport, improve capillary liquid retention, and promote vapor venting, resulting in marked improvements in thermal uniformity. Among the methods tested, natural convection resulted in excessive peak temperatures (>60 °C) and poor distribution, while forced convection provided only marginal gains. Cold plates showed localized cooling but failed to address internal localised thermal gradients effectively. Single-phase immersion cooling with porous media improved uniformity but showed elevated surface temperatures due to limited conductive pathways through the porous layer. In contrast, two-phase immersion cooling, enhanced by latent heat effects and porous structures, achieved the lowest maximum temperatures (<36 °C) and the most uniform thermal profile. These findings establish two-phase immersion cooling with porous enhancement as a scalable, effective, and safety-oriented solution for next-generation battery systems, offering improved performance, lifespan, and integration potential for real-world applications.<br/
Mechanical performance of cold isostatic pressed W-6Ni-4Cu alloy with graphene reinforcements
Get PDFWe have assessed the manufacturability and impact of adding graphene platelets in contents of x = 0, 0.01, 0.05, 0.1 wt.% to W-6Ni-4Cu as a model ‘ductile phase toughened’ tungsten heavy alloy (WHA). These alloys are potential candidates for future nuclear technologies and other structural applications in high-temperature radiation environments. Graphene additions were studied as potential reinforcement and to increase the interface density for mechanical and radiation tolerance of the alloy. The materials were produced successfully by cold isostatic pressing of the pre-mixed powders at a compaction pressure of 140 MPa, followed by liquid phase sintering at 1450-1500 °C under reducing 75% H2/ 25% N2 atmosphere. The graphene platelets are located at the Ni/Cu matrix-W grain and W-W grain interfaces. The material’s density and surface roughness degrade when increasing the graphene content beyond 0.05 wt.%. This is coupled with a sharp reduction in tensile strength and elongation for 0.10 wt.% graphene, whereas those properties undergo an overall increasing trend with graphene content for x ≤ 0.05 wt.%. During tensile deformation of W-6Ni-4Cu (i.e. x = 0), strain localizes primarily in the ductile Ni/Cu matrix and at the matrix-W and W-W interfaces, with crack formation observed at W-W interfaces. However, graphene platelets enhance the load transfer from the matrix to the W grains, and also from grain to grain, therefore promoting a higher degree of cleavage inside the W grains. Graphene additions and cold isostatic pressing offer an avenue to enhance the WHA performance for applications in structures under ever demanding service environments
Biofluid-based predictors of post-concussion symptoms:a narrative review of mild traumatic brain injury biomarkers
Get PDFMild traumatic brain injury can disrupt brain function and is associated with high morbidity and healthcare utilization. While many individuals recover from mild traumatic brain injury, a significant proportion experience long-term sequelae, collectively known as post-concussion syndrome. Symptoms of post-concussion syndrome include headache, dizziness, insomnia, cognitive processing difficulties and mental health disturbances. The disease burden is augmented by the current lack of objective measures to accurately predict long-term symptoms and deficits, providing an opportunity to utilize biomarkers in biofluids. A large proportion of available diagnostic clinical tools are subjective symptom scores. This review aims to explore current fluid biomarkers, grouped by clinical symptoms. With the available literature, we have discovered a wide range of fluid biomarkers that have been investigated for predicting post-traumatic headache, including neuropeptides; sleep disturbances, such as cortisol and melatonin; vestibular disturbances, including interleukin-6 and neurone-specific enolase; and vomiting, such as S100B. Along with physical symptoms, biomarkers investigated for predicting cognitive disturbances include inflammatory markers, S100B, neurofilament light chain, tau, microRNA and hormones. Biomarkers to predict mental health disturbances may include brain-derived neurotrophic factor, tau and cortisol. By utilizing such biomarkers, there is capacity to adopt a personalized medicine approach to facilitate early interventions for those most in need while also identifying individuals with a favourable prognosis who can safely return to their normal activities
Folklore narratives and IPO outcomes
Get PDFOur primary contribution to the finance literature is the introduction of folklore narratives as a major factor in influencing corporate outcomes. Using the initial public offering (IPO) underpricing as the main focus, we demonstrate that folklore narratives depicting lower tolerance toward antisocial behavior are associated with lower IPO underpricing. The relation between folklore narratives and IPO pricing is independent of indicators of trust, religion, culture, societal preferences, or institutional democracy. This relation is weaker in countries with a more transparent information environment and following reforms that improve disclosure and corporate governance. Folklore narratives on punishment for antisocial behavior are also related to enhanced information disclosure, lower agency problems, better long-term performance for IPO firms, higher proceeds raised and free float, and overall IPO activity in the market. Collectively, we show that informal institutions, such as folklore narratives, exert a strong influence on IPO outcomes globally
A Global Survey of Quinacrine Use in Systemic and Cutaneous Lupus Erythematosus
No full textObjective: Experiences with the antimalarial quinacrine for systemic and cutaneous lupus erythematosus (SLE and CLE) remain under-explored. We evaluated and compared dermatologists' and rheumatologists' experiences with quinacrine in managing SLE and/or CLE.Methods: We sent a structured survey to 102 lupus specialists within the Systemic Lupus International Collaborating Clinics (SLICC) and the Canadian Network for Improved Outcomes in Systemic Lupus Erythematosus (CaNIOS), and 200 members of the Rheumatologic Dermatology Society (RDS). Participants responded to questions on self-reported quinacrine prescription history, perceived clinical benefit, reasons for drug discontinuation, and barriers to prescribing.Results: A total of 20 dermatologists from RDS and 40 SLICC and CaNIOS members responded to the survey. All RDS participants (100%) had previously prescribed quinacrine, compared to 17/40 (43%) of SLICC/CaNIOS participants. The majority of quinacrine prescribers (100% RDS, 12/17 [71%] SLICC/CaNIOS) had prescribed quinacrine in combination with another antimalarial. Hydroxychloroquine or chloroquine intolerance (65% RDS, 47% SLICC/CaNIOS) and retinal toxicity (50% RDS, 24% SLICC/CaNIOS) were other reasons for prescribing quinacrine. Clinical benefit was reported by 19/20 (95%) of RDS and 12/17 (71%) of SLICC/CaNIOS clinicians, and discontinuations were less frequent among RDS (5/20 [25%] reported none) compared to SLICC/CaNIOS (all 17 reported ≥ 1). Availability and cost of quinacrine were primary prescribing barriers.Conclusion: Surveyed dermatologists and rheumatologists differed in their experience with quinacrine for CLE and SLE, respectively. Availability remains a key barrier to prescribing, underscoring the need to address supply issues and conduct further research to optimize quinacrine use in SLE and CLE.</p
Measurements of differential cross-sections of <i>WbWb</i> production in the dilepton channel in <i>pp</i> collisions at √<i>s</i> = 13 TeV using the ATLAS detector
Get PDFAt the Large Hadron Collider, the WbWb final state is expected to be dominated by tt- production with a contribution from single-top processes. Differential cross-sections for WbWb production in the dilepton decay channel are measured at the particle level as a function of various kinematic variables. The analysis is based on data from proton-proton collisions at a centre-of-mass energy of √s = 13$ TeV, recorded by the ATLAS detector at the Large Hadron Collider over the period from 2015 to 2018, corresponding to an integrated luminosity of 140 fb−1. Measurements are performed within the fiducial phase-space defined by the presence of two b-jets and one electron and one muon of opposite charges. The differential cross-sections are corrected for detector effects and unfolded to the particle level. Results are compared with predictions from Monte Carlo event generators at next-to-leading order in perturbative quantum chromodynamics. These measurements provide valuable constraints on the modelling of WbWb production and the interference between doubly resonant and singly resonant WbWb production
Protocol for a review of statistical methods used to estimate risk ratios and risk differences in parallel cluster randomised trials
No full textBackgroundCluster randomised trials randomise groups of individuals, such as clinics, schools, or communities, and are used when interventions apply at the group level, when individual-level interventions risk contamination between participants, or to reflect real-world implementation. When outcomes are binary, treatment effects may be expressed as relative measures (such as odds ratios or risk ratios) or absolute measures (such as risk differences). CONSORT guidelines recommend reporting both, but risk ratios and risk differences are often underreported compared to odds ratios. Estimating these measures in cluster trials is more complex than in individually randomised trials, requiring appropriate handling of clustering, convergence issues, and small sample corrections. There is currently little empirical evidence describing which statistical methods are used to estimate these effect measures in published cluster trials.MethodsThis protocol describes the planned methods for a methodological review of published cluster randomised trials. We will use an existing database of 800 trials conducted in low- and middle-income countries. From this, we will identify a subset of trials with a parallel design and a binary primary outcome. Trials reporting a risk ratio or risk difference for the primary outcome will undergo further detailed data extraction. We will summarise the methods used to estimate these effects, including how clustering and small sample sizes were handled, and whether estimates were adjusted for covariates.DiscussionThis review will provide the first detailed description of how risk ratios and risk differences are currently estimated and reported in cluster randomised trials. The findings will inform the development of methodological guidance and help identify gaps in reporting and implementation. This is particularly important as interest grows in improving estimand specification and the clarity of statistical analysis plans
Novel scroll tip modification:development and validation of scroll expander for compressed-air energy storage
Get PDFScroll expanders are promising components for micro-scale Compressed-Air Energy Storage (mCAES) systems due to their compactness, oil-free operation, and high efficiency. However, their performance is highly sensitive to both scroll geometry and the matching of built-in volume ratio (Rv) with operating pressure. This study investigates a novel scroll tip modification called Lip Spoiler (LS) and is aimed at improving expansion ratio, eliminating suction blockage, and enabling efficient expansion within shorter scroll lengths. A fully deterministic 1-D MATLAB model was adapted and experimentally validated using three scroll expander prototypes with different built-in volume ratios (Rv = 3.5, 3.0, and 2.5). Results show that reducing Rv from 3.5 to 2.5, in consistent with a 3-bara inlet pressure, achieves adaptive expansion, leading to a 12 % increase in isentropic efficiency and a 27 % improvement in power output. Incorporating the LS tip design at Rv = 2.5 further enhances performance, reaching 72 % efficiency and 176 W output, representing a 32 % power gain compared to the baseline design. These findings demonstrate that both precise volume ratio selection and scroll tip optimization are critical for maximizing scroll expander performance in CAES systems, offering a scalable and efficient solution for renewable energy storage
Can AI streamers’ perseverance and exceptional intelligence overcome KOLs’ viewership moat?
Get PDFTo examine the optimal live-streaming model for manufacturers and its influencing factors under artificial intelligence (AI) conditions, this study introduces two variables: the intelligence level of AI streamers and livestream duration sensitivity. Two models are constructed, solved using optimization theory, and evaluated through comparative and sensitivity analyses. The findings are as follows: (1) Compared with Key Opinion Leader (KOL) live streaming, AI live streaming does not always lead to higher profits for manufacturers. AI streamers with greater endurance and intelligence are preferred only under specific conditions. (2) Manufacturers will opt for AI live streaming under four scenarios: high livestream duration sensitivity, moderate livestream duration sensitivity with high-intelligence AI streamers, high commission rates with low livestream duration sensitivity, high commission rates combined with moderate livestream duration sensitivity and low-intelligence AI streamers. (3) Although AI live streaming can effectively lower live streaming costs, manufacturers do not necessarily implement price reduction strategies accordingly. Only when both livestream duration sensitivity and the intelligence level of AI streamers are low do manufacturers potentially reduce prices to compensate for any negative experiences resulting from suboptimal live-streaming effects. Additionally, the study further explores four different scenarios, including KOLs' fixed fees, AI streamers with higher intelligence than KOLs, one-time investment costs for AI live-streaming, and AI streamers without popularity, thereby validating the robustness of the constructed model
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