Public Health and Healthcare

Abstract: Background/Objectives: Aluminum-adjuvanted vaccines are widely used in pediatric immunization, yet particle size and distribution are critical but under-standardized quality attributes. Methods: This study aimed to establish and validate a laser diffraction particle size analysis for evaluating particle size consistency and stability of inactivated enterovirus 71 (EV71) vaccine and adsorbed acellular diphtheria–tetanus–pertussis (DTaP) vaccine. Results: EV71 vaccine stock solution (40–350 nm) and aluminum adjuvant (75–600 nm) exhibited distinct distributions, with the final product showing bimodal distribution (50–14,000 nm): main peak at 0.1–0.2 μm (~65%) and secondary peak at 0.3–3 μm (~14%). DTaP final product (2000–20,000 nm) showed significant aggregation with 79.6% at 3–8 μm and 15.7% at >8 μm. Four EV71 batches (A1–A4) showed uneven inter-batch consistency (D50: 100, 132, 103, 103 nm; CV 13.8%), while intra-batch CVs were acceptable (3.9% for EV71, 8.0% for DTaP). Long-term stability at 4°C revealed gradual aggregation: EV71 D50 increased from 100 nm to 134 nm over 60 days, with >0.2 μm aggregates increasing from 0.03% to 1.50%; DTaP showed severe tailing at day 60 (>50 μm particles: 2.8%). Accelerated studies showed 37°C caused slight enlargement, whereas −20°C induced marked aggregation (EV71 D50: ~37 μm, CV 16.1%; DTaP D50: ~45 μm, CV 13.8%). Conclusions: Laser particle size analysis is a robust, reliable tool for assessing particle size consistency and stability of aluminum-adjuvanted vaccines. It supports process control, batch release, and stability monitoring to improve vaccine quality and safety.

Abstract: Oral squamous cell carcinoma (OSCC) remains a major contributor to global head and neck cancer morbidity and mortality. This review examines the epidemiological aspects of OSCC and the biological mechanisms through which established exposures (e.g., tobacco, alcohol, betel/areca nut, socioeconomic and selected viral infections etc.) and emerging determinants (oral microbiome dysbiosis, host genetics/epigenetics, and immune dysfunction) converge to initiate and promote malignant transformation. We emphasize that OSCC risk is probabilistic and multifactorial: incidence rises markedly with age and cumulative exposures, yet the majority of individuals risk exposed to these risk factors will not develop disease. Mechanistically, carcinogen-driven DNA damages intersects with dysbiosis characterized by enrichment of periodontal pathobionts (notably Porphyromonas gingivalis and Fusobacterium nucleatum), which can sustain chronic inflammation, increase local generation of acetaldehyde and nitrosamines, and promote immune evasion via expansion of immunosuppressive cell populations and checkpoint signaling. We summarize recurrent molecular and genetic alterations in OSCC and highlight progress in early detection, including adjunctive visualization, optical and vibrational spectroscopy, and liquid-biopsy approaches using salivary and blood-based biomarkers. Finally, we discuss prevention opportunities spanning risk-factor modification, historical cultural practices, oral hygiene to mitigate dysbiosis (pH modulation and probiotics), and dietary/nutritional strategies. Integrating exposure history with microbial and molecular profiling may enable risk-stratified screening and prevention paradigms for OSCC.

Abstract: The need to reduce harmful emissions and fossil fuel consumption has spurred the development of environmentally friendly technologies in the energy, industrial, and transportation sectors. One approach to addressing this problem is the active adoption of electric and hybrid powertrains in transportation, partially replacing internal combustion engines with them. With the development of electric transport, the growth of energy availability and the increase in mileage, the problem of ensuring optimal thermal conditions for the operation of engines, electronics, batteries and other equipment of electric vehicles is becoming increasingly important. This article examines methods for thermal management of electric vehicle equipment and the feasibility of using heat pipes and thermosyphons for these purposes. Based on the information obtained, the goal was to propose an effective, compact device for passive cooling of heat-loaded components in electric vehicles. The design and test results of an aluminum loop thermosyphon with two evaporators are presented. This loop thermosyphon is capable of simultaneously removing heat from two sources and transferring it to a single heat sink, thus replacing two thermosyphons and increasing the compactness of the thermal management system.

Abstract: Foodborne mycotoxins are toxic secondary metabolites produced by filamentous fungi. At sufficient concentrations, ingested mycotoxins have been found to disrupt the microbiome and exert toxic effects on gastrointestinal, hepatic, renal, and other tissues. Toddlers are particularly vulnerable to ill effects due to increased intake relative to lower body weight and immature detoxification, metabolic, and immune function. Despite this susceptibility, their adverse health effects remain under-recognized in public health sectors, and data on mycotoxin contamination in foods marketed to young children in North America remain sparse. To investigate this, 118 food products, including cereals, snacks, pasta, first foods, juices, and staple ingredients, were purchased at retail and analyzed for 34 mycotoxins using liquid chromatography–tandem mass spectrometry. The results were compared with United States Food and Drug Administration (FDA) regulatory thresholds and European Tolerable Daily Intake (TDI) limits. At least one mycotoxin was detected in 88 percent of products, with a mean of 3.8 per item and a maximum of 13; 26 of 34 analytes were identified. Multi-toxin contamination was common, many products exceeded FDA and TDI limits, and many remain unregulated. These findings highlight regulatory gaps in food safety and underscore the need for stronger child-focused oversight, particularly regarding emerging mycotoxins and multi-toxin contamination.

Abstract: Background: The Dietary Inflammatory Index (DII®) is a commonly used tool to assess diet-related inflammation. Higher DII scores are associated with increased cardiovascular disease risk in large observational cohorts yet, controlled-trial evidence evaluating cardiovascular outcomes across DII levels is scarce. This secondary analysis examined cross-sectional differences and longitudinal associations between dietary inflammatory potential and cardiovascular outcomes in healthy Australian adults. Methods: In a double-blind randomised crossover trial, 50 participants consumed 60 mL/day of either high-phenolic (320 mg/kg) or low-phenolic (86 mg/kg) olive oil for two 3-week intervention periods, separated by a 2-week washout. Anthropometry (weight, height, waist circumference, BMI) and cardiovascular outcomes (i.e., blood pressure, lipids, oxidised LDL, and HDL-cholesterol efflux capacity) were measured at four timepoints. DII and energy-adjusted DII (E-DIITM) scores were calculated from 3-day food diaries at baseline and follow-up of each 3-week intervention phase. Linear mixed-effects models compared cardiovascular outcomes across DII tertiles (low, medium, high) adjusting for intervention, period, sequence, age, sex, and waist circumference. Results: Forty-three participants completed the study. At baseline, BMI, waist circumference, systolic blood pressure, total cholesterol, and LDL differed significantly across DII tertiles (p<0.05). Across the study period, cardiovascular outcomes did not differ between medium or high versus low DII tertiles, and no significant time-by-tertile interactions were observed (all p>0.05). DII values remained stable across timepoints, while E-DII decreased modestly within individuals in both intervention periods. Conclusions: In this healthy cohort, DII was not associated with adverse short-term changes in cardiovascular outcomes. Longer-duration studies with greater contrast in dietary inflammatory potential are warranted to clarify the relationship between DII and cardiovascular health.

Abstract: Background/Objectives: The use of IgM- and IgA-enriched intravenous immunoglobulins (eIg) in septic shock remains controversial due to the lack of high-quality evidence, despite indications from observational studies and meta-analyses suggesting potential benefit. Identifying patients who may respond favorably and determining whether extended treatment could be useful are ongoing challenges. This study evaluates baseline predictors and early treatment-related trends associated with outcomes in septic shock patients receiving eIg, with particular focus on immunoglobulin levels and norepinephrine (NE) requirements. Methods: This observational analysis used data from the multicenter SORRISO registry, including 248 septic shock patients treated with eIg from 2015 to 2022. Baseline clinical and biochemical variables were recorded at the start of eIg infusion (D0). Trends in IgA, IgG, IgM, lactate, and NE dose were assessed between D0 and D4. Restricted cubic spline (RCS) models examined non-linear associations with mortality, and Kaplan–Meier analyses evaluated 28‑day survival according to parameter trends. Statistical significance was defined as p < 0.05. Results: RCS curves showed no prognostic value at D0 for INR, CRP, PCT, IgA, or IgG. Lactate (p = 0.005) and platelet count (p = 0.001) demonstrated significant associations with mortality, while IgM (p = 0.076) and NE (p = 0.059) approached significance. Of 209 evaluable patients, NE requirements decreased in 191 (NE‑DOWN) and increased in 18 (NE‑UP). Survival was 67% in the NE‑DOWN group vs. 23% in NE‑UP (p < 0.0001). No D0 variable reliably predicted NE trajectory. In conclusion, among septic shock patients treated with eIg, increasing NE requirements during the first four days were strongly associated with higher mortality. Baseline biomarkers did not predict vasopressor trends.

Abstract: Generalized anxiety disorder (GAD) is characterized by persistent, excessive, and difficult-to-control worry. The Contrast Avoidance Model (CAM) proposes that individuals with GAD use worry to sustain negative emotional arousal, thereby avoiding sharp negative emotional contrasts that would otherwise follow unexpected adverse events. A virtual reality (VR) protocol was developed to simulate such contrasts by alternating guided relaxation with brief anxiety-inducing scenarios (skyline plank, crowded elevator, and loose dog encounter). This study evaluated the usability and feasibility of this protocol in 20 subclinical adults aged 18–45 (GAD-7 ≥ 5) using a Meta Quest 3 headset and Polar H10 heart rate sensor. Exposure segments produced a significant decrease in RMSSD (β = −0.185, p < .001), confirming reduced parasympathetic activity during anxiety induction, whereas heart rate did not differ significantly between conditions. Subjectively, exposure increased SUDS (β = 2.23, p < .001) and SAM arousal (β = 1.95, p < .001), and decreased SAM valence (β = −2.68, p < .001) and dominance (β = −1.70, p = .005). Higher baseline anxiety was associated with attenuated heart rate reactivity, consistent with CAM predictions. Presence was sufficient for emotional engagement, cybersickness was low, and qualitative feedback yielded concrete design refinements. These results establish a foundation for clinical investigation of contrast-based VR interventions for GAD.

Abstract: Background: Variation in suspected adverse drug reactions (SARs) linked to different batches of COVID-19 vaccines has been reported in several countries, including the Czech Republic, Denmark, Sweden, and the USA. However, SAR data from spontaneous reporting systems are subject to under-reporting and other biases. To investigate the potential association between vaccine batches and adverse reactions using an unequivocal endpoint, we examined the temporal relationship between all-cause mortality (ACM) and COVID-19 vaccine type and batch up to three months after vaccination.Methods: We analysed nationwide data from the Czech Republic on vaccine type and batch, together with corresponding three-month ACM data. Cluster analysis was used to assess age- and sex-specific differences in ACM within and across vaccine batches and types. We also investigated the relationship between ACM and SAR rates for the same batches.Results: During a 21-month period (December 2020 to September 2022), vaccine batches clustered according to their three-month age- and sex-adjusted ACM rates for the four products administered (Comirnaty, Spikevax, Vaxzevria, and Jcovden). For Comirnaty, Spikevax, and Vaxzevria, a clear temporal pattern was observed, with earlier batches showing significantly higher ACM rates. A strong correlation was found between batches that clustered by ACM and those previously identified as clustering by SARs, across all vaccine products except Jcovden.Conclusions: Data from the Czech Republic show a clear association between administered COVID-19 vaccine batches and 3-month ACM rates for Comirnaty, Spikevax, and Vaxzevria, with earlier batches linked to notably higher ACM. A strong correlation between batch-associated ACM and SAR rates for Comirnaty and Spikevax supports the validity of these batch-related safety signals and warrants further investigation using individual-level patient data.

Abstract: Background/Objectives: This study describes the development and validation of the Danish Sentence Test (DAST), a Danish-language, adaptive speech-in-noise test constructed from a linguistically balanced corpus using a template-based method. This approach enables controlled linguistic variation while maintaining lexical consistency and may serve as a model for developing similar speech materials in other languages. Methods: Sentences spoken by one female talker from the DAST corpus were sorted into 44 balanced lists of 20 sentences using a psychometric optimization procedure. Speech reception thresholds (SRTs) were measured in 20 normal-hearing participants using headphone playback with speech-shaped noise. Results: The mean SRT across lists was −5.3 dB SNR, with list means within ±0.5 dB of the grand average. The average within-subject standard deviation was 0.7 dB, and the grand average psychometric slope was 18.5%/dB. A relatively small training effect was observed, consistent with the use of linguistically varied, low‑predictability material. Conclusions: DAST provides a linguistically rich and psychometrically well-controlled speech-in-noise test with substantially more material than existing Danish corpora. The template-based method and optimization approach may be of broader methodological interest for developing speech materials in other languages. DAST complements existing Danish-language tests and enables more extensive assessments of speech understanding, including studies requiring large numbers of non-repeated sentence lists.

Abstract: The incidence of insulin resistance and its complications is rising across societies worldwide, making its treatment a significant economic challenge. The disease is multifactorial, and its pathophysiology varies accordingly. Genetic factors, aging, and coexisting diseases are major contributors to its development. Among the coexisting conditions are autoimmune diseases and other conditions requiring treatment with therapeutic agents, some of which can induce insulin resistance. Research indicates that the free radical theory plays a significant role in initiating this complex cycle and in shaping the full clinical picture of diabetes syndrome. In this work, we discuss the pathophysiology of insulin resistance, the role of free radicals in its etiology, and drug treatments for diseases that may contribute to insulin resistance. We also explore the antioxidant effects of vitamin D and oral hypoglycemic agents, as well as their notable adverse effects, including cobalamin (vitamin B12) deficiency. A total of 147 scientific studies, including comprehensive meta-analyses, have been selected to address these questions and have been analyzed and discussed objectively to minimize scientific bias and confusion. This narrative work will help doctors and primary health caregivers envision the dimensions of diabetes syndrome from multiple perspectives and update their knowledge about the significance of vitamin D as an effective tool to combat insulin resistance.

Abstract: Background: Substance Use Disorder (SUD) is characterized by recurrent craving episodes frequently associated with emotional dysregulation and altered reward processing. This study aimed to evaluate whether emotional states associated with craving episodes can be detected through automated facial emotion recognition during controlled emotional induction. Methods: Forty-one participants completed a 14-day ecological momentary assessment (EMA) monitoring anxiety and craving levels, followed by an emotional induction task using standardized stimuli from the EmoMadrid database and addiction-related images. Facial expressions were recorded and analyzed in real time using a computational facial emotion recognition model trained on the FER-2013 dataset. Results: Participants with SUD exhibited significantly reduced positive emotional valence and activation in response to positive stimuli compared with HC (p &lt; 0.01). Item-level analyses revealed that most differences occurred in stimuli depicting social interactions. Positive emotions and energy were linked to less intense cravings and shorter substance use. People with SUD showed more fear and less disgust in their facial expressions than controls (p = 0.02). Conclusions: These results suggest that people with SUD have changes in how they process emotions, showing less response to positive things and unique facial expressions related to craving.

Abstract: High consumption of ultra-processed foods (UPFs) contributes to the growing burden of non-communicable disease, yet many consumers struggle to recognise and interpret levels of processing. Digital tools using artificial intelligence (AI) offer potential to support nutrition literacy and UPF awareness. This study explored user perceptions, usability and cultural relevance of a Human Interference Scoring System (HISS)-based mobile application designed to classify foods and support reflection on food quality and dietary choices. A qualitative study was conducted in New Zealand, where participants used the HISS app for three days followed by semi-structured interviews. Thirty-one participants were recruited via social media and word of mouth, including adolescents (n=13), tertiary students (n=9), and Māori and Pacific health coaches (n=9). Transcripts were analysed using inductive thematic analysis. Three evaluative categories were identified: positive user experiences (intuitive interface, perceived AI accuracy, enhanced nutrition literacy, visual feedback, inclusivity of cultural foods); challenges (technical issues, database gaps, limited depth for advanced users); and suggested improvements (expanded food database, enhanced logging, culturally tailored education, optional advanced features). Participants reported increased awareness of UPF intake and reflection on food choices. The HISS app was perceived as usable, acceptable and relevant across diverse user groups, particularly for those with lower nutrition literacy. Addressing technical limitations and expanding functionality may enhance engagement and applicability. AI-enabled, culturally responsive food classification tools such as HISS show promise as scalable health promotion approaches to support UPF awareness and dietary reflection in community and clinical settings.

Abstract: Background: Retained surgical items (RSIs) remain preventable never events associated with failures in counting processes, communication, documentation, and perioperative safety culture. Although patient safety in the operating room has been widely studied in healthcare teams, evidence remains limited regarding how these competencies are developed during undergraduate surgical instrumentation training, particularly in Latin American settings. Objective. To assess knowledge, safe practices, and perceived safety culture related to RSI prevention among surgical instrumentation students in clinical training at a university in Barranquilla, Colombia. Methods. A quantitative cross-sectional study was conducted among students in advanced semesters of a Surgical Instrumentation program. Data were collected through a structured, self-administered questionnaire that included sociodemographic characteristics, knowledge of RSI prevention, safe perioperative practices, perceived safety culture, and need for further training. The instrument showed good internal consistency (Cronbach’s alpha = 0.88) in the 48 completed questionnaires analyzed. Descriptive statistics were calculated for all variables. Because of sample size and ordinal outcomes, Mann-Whitney U, Kruskal-Wallis H, and Spearman’s rho were used. Results. A total of 48 complete questionnaires were analyzed. Mean age was 21.10 years (SD 2.25), and 75.0% of participants were women. Global knowledge scores were high (mean 8.60/9; SD 0.92), with ceiling effects across several items. Safe practices (mean 4.58/5; SD 0.63) and safety culture (mean 4.67/5; SD 0.49) were also high overall. However, lower-performing items were institutional count documentation, verification during staff handovers, and requesting a formal count pause. Knowledge scores were significantly higher among students reporting prior training in count/recording procedures (p=0.018). The strongest association was a moderate positive correlation between safety culture and safe practices (rho=0.520; p<0.001). Conclusions. Surgical instrumentation students showed strong theoretical knowledge and favorable self-reported preventive practices regarding RSI prevention. Nonetheless, important gaps persisted in handover verification, institutional documentation, and count-pause activation. The positive association between safety culture and safe practices suggests that undergraduate perioperative education should integrate technical counting skills with structured communication, supervision, teamwork, and speaking-up behaviors.

Abstract: Accurate reconstruction of epidemic dynamics is challenging when reported infection data are incomplete or affected by significant under-reporting. Excess mortality indicators provide an alternative source of information that can be used to infer epidemic trajectories. In this study, we propose a regularized inverse calibration framework for a SEIRD epidemi-ological model using excess mortality data. The calibration problem is formulated as an inverse problem and stabilized through a Gaussian functional regularization that constrains the admissible epidemic trajectories. This approach reduces sensitivity to noise in mortality observations and prevents oscillatory solutions typically associated with ill-posed param-eter estimation. The model is numerically integrated using a fourth-order Runge–Kutta scheme and calibrated against mortality data from Catalonia. Cross-context validation is further performed using mortality data from Ecuador to assess the structural robust-ness of the approach. The results show that the regularized calibration produces smooth and epidemiologically consistent epidemic trajectories while maintaining agreement with observed mortality patterns. The proposed framework provides a robust methodology for reconstructing epidemic dynamics from mortality indicators and may contribute to improved epidemiological surveillance in situations where case reporting is limited or unreliable.

Abstract: Medical schools play a significant role in cultivating an inclusive health system. In 2019, the University of Miami Miller School of Medicine was ranked as the 6th best graduate school in the U.S. for Diversity when the Racial Justice Report Card assigned this institution lowest grade possible. To better understand perceptions of inclusivity among students, faculty, and staff, a campus-wide evaluation was conducted. A mixed-methods survey was administered to query perceptions of on-campus discrim-ination and overall campus climate. In addition to multiple choice items, participants were invited to detail their experiences in an open-ended format. Among 1,612 re-spondents, the majority were women (67%) over the age of 60-years (60%). Two-thirds of respondents were staff, 20% faculty, and 12% students. Quantitative analyses showed significant associations among race, gender, and perception of campus cli-mate. Three major themes emerged from analysis of the open-ended items: (1) inclu-sion & belonging; (2) upward mobility; and (3) the minority tax. A lacking sense of be-longing was reported across all demographic groups, with Black respondents express-ing the ‘minority tax’ was disproportionately imposed, burdening them with the un-compensated task of fostering an inclusive culture. Results demonstrate the value of U.S. Medical Schools’ assessing the cultural climate to yield findings that guide devel-opment and implementation of institutional strategies that advance an inclusive cul-ture. Progress evaluations from external reviewers would further support future inclu-sivity-enhancement efforts and may ultimately lead to an improved cultural climate at U.S. medical schools.

Abstract: Upper respiratory tract infections such as the common cold are highly prevalent and impose a substantial health and economic burden, with many individuals relying on over-the-counter (OTC) medications for symptomatic relief despite limited real‑world evidence on perceived effectiveness. This non‑interventional, retrospective, cross‑sectional survey evaluated the product attributes most valued when selecting cold and flu medications and assessed perceptions of the effectiveness, quality‑of‑life impact, and overall attitudes toward MED‑LEMON. A total of 249 adults completed a structured questionnaire covering symptom relief priorities, medication attributes, perceived effectiveness, quality of life outcomes, and post-intake attitudes. Relief of fever, sore throat, headache, and sinus congestion, along with fast action, long‑lasting relief, and ease of use, were identified as key drivers of OTC cold and flu medication choice. MED‑LEMON was widely perceived as effective, with over 90% of participants reporting overall symptom improvement and strong relief of pain, headache, and fever. Adherence to the recommended dosing regimen was associated with better symptom control and improved quality of life, including sleep, emotional well‑being, and daily functioning. Overall attitudes toward MED‑LEMON were highly positive. From a public health perspective, these findings highlight the role of effective OTC treatments in supporting health promotion and responsible self-care during cold/flu period.

Abstract: Background: The aim of this study was to investigate the effect of 2% chitosan nanoparticles (NPs) as an irrigating solution during pulp revascularization of immature dog teeth using histological and histomorphometric analyses. Materials and Methods: Pulp necrosis and periapical pathosis were induced in 52 incompletely formed roots in four dogs (6-8 months age). These teeth were randomly allocated to Group I (n = 20; irrigation with NaOCl + EDTA), Group II (n = 20; irrigation with NaOCl + chitosan NPs), DAP was used as a medication in both groups. Positive control (6 roots): teeth with induced periapical infections, no treatment procedure, and left open. Negative control (6 roots): teeth that were left untreated for the normal maturation process. Each experimental group was subdivided into 2 divisions in accordance with the post-treatment evaluation periods (1- 3 months). The experimental teeth were re-entered following the infection period and disinfected using the assigned irrigation and medication protocol, and the access cavities were sealed. After the evaluation period, medication was removed, and blood clot formation was created through over-instrumentation. Mineral trioxide aggregate (MTA) was applied, followed by glass ionomer restoration (GIC). Results: At both 1 and 3 months, Group II demonstrated significantly superior histological organization and higher collagen-positive area percentages compared with Group I (p &lt; 0.01), while the negative control showed the highest values and the positive control the lowest. Conclusion: Irrigation with 2% chitosan NPs significantly improved regenerative outcomes compared with the conventional NaOCl/EDTA protocol in immature canine teeth.

Abstract: Wound infections result from contamination of a compromised skin following either intentional or accidental trauma. Failure of wound to heal can be due to mixed infections, with huge impact on global healthcare finances. For surveillance purposes, this investigation looks at wound infections and their susceptibility to antibiotics. Data obtained from the Microbiology laboratory achieves for the years 2014 and 2019 were wound characteristics, patient demographics and causative bacteria pathogen. Also retrieved from the -80° C freezer were 270 Gram-negative bacteria isolates from wounds that formed part of patient care. Vitek Compact 2 was used for bacteria IDs and AST testing. Wound swabs were in majority (74.07%) followed by bedsore samples (12.22%). Others were tissue cultures (6.3%), skin swab (3.7%) necrotizing fasciitis (1.48%), foot swabs (1.10%) and cervical wounds (1.11%). Isolated pathogens included Pseudomonas aeruginosa (33.6%), Escherichia coli (24.78%), Acinetobacter baumannii (21.85%), Klebsiella pneumoniae (17.65%), Proteus mirabilis (1,7%) and Morganelli morganii (0.41%). Most isolates had become MDR after 5-years with extensive (100%) resistance to β-lactam and fluoroquinolone. Only tigecycline and amikacin maintained their antimicrobial activity for the period with some bacteria species. Suitable therapeutic options were few irrespective of the year of isolation particularly among the ESKAPE isolates. Overall results demonstrates that after a 5-year period about 75% of the isolates of the bacteria pathogens had become resistant to most of the antibiotics used for their management.

Abstract: Traditional MRI systems rely on large liquid-helium baths to maintain superconductivity, requiring complex infrastructure, quench pipes, and ongoing helium supply management. Modern “dry” or micro-helium MRI magnets replace this approach with conduction cooling and sealed helium volumes of only a few liters or less. These systems drastically reduce helium dependence, eliminate routine refilling, simplify installation, and lower lifetime operating costs. The major practical advance comes from moving from open helium baths to sealed systems rather than from differences between small helium volumes (e.g., 0.7 vs. 7 liters). Smaller volumes mainly influence safety margins and resilience during power interruptions rather than routine clinical operation.

Abstract: Rapid antigen tests targeting SARS-CoV-2 nucleocapsid protein were essential for decentralised testing during the COVID-19 pandemic. Independent performance evaluations are critical to guide regulatory approval and implementation, particularly in resource-limited settings. This study presents a retrospective analytical and operational evaluation of two instrument-based fluorescent immunoassays (FIA): the PCL COVID-19 Ag Rapid FIA (PCL Inc., South Korea) and LumiraDx SARS-CoV-2 Ag Test (LumiraDx Ltd., UK). Analytical sensitivity was determined using recombinant nucleocapsid protein and viral cultures. Clinical performance was assessed using residual clinical specimens (n=110) with RT-PCR as reference, stratified by cycle threshold (Ct). Operational characteristics were assessed using a structured Likert framework. Overall sensitivity was 63% (51-73) for PCL and 95% (88-99) for LumiraDx. For Ct≤25, sensitivity increased to 93% and 100%. Specificity was ≥97% for both. LumiraDx maintained sensitivity (83-94%) at Ct 25-30, whereas PCL detected no positives in this range. Limit of detection was 0.039 nM (PCL) and 0.6 pM (LumiraDx). Operational usability was high for both (90% PCL, 87% LumiraDx). LumiraDx showed higher analytical sensitivity across a broader viral load range, supporting primary diagnostic use, whereas PCL was limited to high viral loads. This provides a reproducible framework for rapid diagnostic assessment during emerging outbreaks.