Eruption of volcanoes is associated with the emission of great energy through the propagation of atmospheric waves up into space. These waves cause significant disturbances in the ionosphere, a region that contains a large number of ions and electrons and is important in providing communications through radio waves and satellites. Disturbances may cause the formation of Equatorial Plasma Bubbles and low-density pockets, leading to signal distortion, time delays, and sometimes, loss of signals in satellites. The Global Positioning System (GPS) becomes inaccurate due to these disturbances since GPS uses information on the positions of user locations. Satellite-based services like the internet and telephony may be affected by the disturbances in the ionosphere caused by a high number of electrons. Prediction of these disturbances makes it possible to plan ways of mitigating against them during future eruptions. Total Electron Content (TEC) data used in this research were mainly obtained from the BAKO station in Indonesia, in addition to other latitudes, in order to prove the universality of the model. The Hybrid Machine Learning and Deep Learning (ML-DL) Model, which is a combination of Light Gradient Boosting Machine (LightGBM) and Long Short-Term Memory networks (LSTM) algorithms, was designed based on a weighted average and applied in forecasting TEC values. Performance of the model was compared with other independent models, i.e., individual LightGBM and LSTM, as well as the conventional Autoregressive (AR) and Multiple Linear Regression (MLR) models. Four evaluation measures were used in evaluating the performance of models. This study aims to assess the performance of the Hybrid ML-DL Model in predicting TEC during ionospheric disturbances caused by volcanic eruptions. TEC prediction was done in six major eruptions, including Mt. Kelud (2014), Mt. Sinabung (2016), Mt. Semeru (2021), Mt. Ruang (2024), Mt. Etna (2013), and Mt. La Soufriere (2021). The Hybrid ML-DL Model consistently performs better than the individual LightGBM and LSTM models and the traditional AR and MLR models in predicting TEC values. For example, during the Mt. Ruang eruption, which was the highest eruption disturbance analyzed with a maximum disturbance of 100-110 TECU between April 16th and May 7th, 2024, the Hybrid ML-DL Model scored an RMSE of 2.841 TECU, which was much lower than RMSE values of LightGBM (3.484 TECU), LSTM (5.084 TECU), MLR (5.345 TECU) and AR Model (6.285 TECU). The Hybrid ML-DL Model showed the least value in three performance evaluation criteria, including NRMSE (0.030), MBD (0.546 TECU), and RLE (0.069) among other models.
Transgene-free gene-editing has transformed the genomic landscape of crops by enabling targeted, precise, and predictable genetic outcomes without integrating any foreign DNA into the host genome. It has significantly reduced production time and costs, and the regulatory burden for transgene-free gene-edited crops, while improving social acceptance compared with classical transgenic crops. This review compares the transgene-free gene-edited, transgenic, and cisgenic crops. We also focus on core methods for developing transgene-free gene-edited crops, particularly ribonucleoprotein (RNP), transient expression, the transgene killer method, and HI-edit technology. We highlight the practical examples summarizing CRISPR applications for transgene-free gene-edited crops, including cereals, legumes, and oilseeds, and horticultural crops. We also analyze the rapidly evolving global regulatory landscape of transgene-free gene-edited crops, including the recent European Union movement towards differentiated oversight for certain "new genomic techniques (NGTs)" that do not introduce foreign DNA, while maintaining the strict risk assessment for complex modifications. We also summarize the social, ethical, and public perception aspects of transgene-free gene-edited crops compared with traditional GMOs. Finally, we highlight the emerging role of AI in developing precise transgene-free gene-edited crops and the contributions these crops make to global food security. Collectively, this evidence supports the growing role of transgene-free gene-edited crops in scientific developments and real-world agricultural deployment, with remaining bottlenecks in delivery for recalcitrant crops, scalable and universal regulation, detection and traceability of the Cas footprints, and equitable access.
Availability of the hepatitis B virus (HBV) vaccine in the United States since 1982 and recommendations for universal/catch-up vaccination of infants and children since the 1990s may be associated with lower HBV prevalence among people with human immunodeficiency virus (HIV; PWH) born after 1980. Active HBV infection prevalence, defined as the proportion of patients with a positive hepatitis B surface antigen result, was assessed among PWH at entry into a clinical cohort. Patients were categorized into birth-year cohorts of 1940-1959, 1960-1979, or 1980-1999 and then further dichotomized into pre- and post-1980 birth-year cohorts. Log binomial regression was used to assess the association of birth-year cohort with hepatitis B surface antigen positivity, adjusting for race/ethnicity, HIV infection risk factor, baseline HIV viral load and CD4+ cell count, HBV active therapy, and year of/age at cohort entry. Among 5598 PWH, most were male (67%) and Black (77%), with a mean age (SD) of 39.7 (9.6) years at cohort entry. Approximately a third of the participants (30%) identified as men who have sex with men, and 39% reported a history of injection drug use. At cohort entry, the majority had a CD4+ cell count <350/µL and a viral load >1000 copies/mL. The HBV prevalence was 6.7% overall but varied by birth-year cohort: 6.2% for 1940-1959, 7.9% for 1960-1979, and 2.6% for 1980-1999. The risk of HBV infection was lower in the post-1980 than in the pre-1980 cohort (adjusted prevalence ratio, 0.19 [95% confidence interval, .09- .42]). PWH born after 1980 had a lower prevalence of HBV coinfection than those born before 1980, supporting the potential impact of universal childhood HBV vaccination.
Phenotypic plasticity is a universal property of living organisms, denoting the ability of a single genotype to produce different phenotypes in response to environmental variation (Bradshaw, 1965). This fundamental property is particularly relevant for plants which, due to their sessile nature, must rapidly respond to accommodate effects of global change on their development, growth, and reproduction (Schneider et al., 2026). Therefore, there has been a recent growing interest to uncover the genetic and molecular mechanisms underpinning phenotypic plasticity, with particular focus on agronomically relevant focal traits in different crops (Li et al., 2021; Liu et al., 2021).
The US Defense Health Agency (DHA) maintains five Institutional Review Boards (IRBs) within the Office of Human Research Protection Human Research Protection Program (HRPP) to oversee the research portfolio. DHA researchers completed the IRB Researcher Assessment Tool (IRB-RAT) to share their perceptions of IRB performance and identify areas where future process improvement efforts can be focused. This study was a cross-sectional programme evaluation and IRB determination was received. Participants were asked to complete the IRB-RAT. The primary outcome was the performance gap score, calculated for each item as Actual minus Ideal. Linear mixed-effects models were used to analyse responses and to evaluate institutional variability. An electronic invitation to complete the IRB-RAT was sent to 5960 registered DHA Electronic IRB system (EIRB) users between May and October 2025. Of those, 473 responded. Analysis identified the most important Ideal characteristics as (Q1) timeliness, (Q4) providing complete explanations for changes and (Q25) not using its power to suppress research. The largest performance gap scores were (Q1) timeliness, (Q24) being an ally rather than a hurdle and (Q15) accountability for errors or delays. Items identified for process improvement were (Q1) timeliness, (Q4) providing complete explanations for changes, (Q24) being an ally rather than a hurdle and (Q22) understanding and acting within their scope of function. There were significant differences across the five IRBs. Performance was not uniform across the DHA. The IRB-RAT effectively captured respondents' perceptions of DHA IRB performance. Timeliness was a universal concern and improvements within IRB scope of function and providing explanations for changes should help minimise delays. Additional work is needed to understand why DHA researchers view the IRB as a hurdle, not an ally. The DHA IRBs must harmonise best practices across the five IRBs and develop future process improvement projects to address researchers' concerns.
Short-form video platforms have become a central psychological environment in university life, yet their mental health significance cannot be explained by total screen time alone. This hypothesis-and-theory article develops the Motivation-Affordance-Capacity-Outcome framework (MACO) to explain why similar short-form video duration may produce protective, neutral, problematic, or clinically meaningful outcomes among university students. MACO is revised here as a shorter, more testable, and platform-specific framework. Its distinctive contribution rests on three mechanisms: session-in-context analysis, motivational drift, and algorithmic feedback loops. The framework argues that entry motives are translated by short-form-video affordances into engagement modes; that self-regulatory capacity and baseline vulnerability shape whether use remains flexible; and that algorithmic feedback can stabilize either adaptive or maladaptive patterns over repeated sessions. The article clarifies how MACO differs from I-PACE, the active-passive model, compensatory Internet use theory, and differential susceptibility approaches by generating comparative predictions about short-form video versus long-form video, text forums, traditional television, and general social media. It also specifies falsifiable propositions, disconfirmation criteria, and operational indicators for constructs such as motivational drift, socially saturated loneliness, perceived algorithmic agency, and motivational alignment. Particular attention is given to Chinese and East Asian university contexts as theoretically important boundary conditions rather than assumed universal settings. The framework supports interventions that move beyond generic screen-time reduction toward motive-specific diagnosis, digital mindfulness, sleep-protective friction, credibility support, platform design changes, and culturally responsive mental health education.
Socioeconomic factors and atypical femur fracture (AFF) risk during bisphosphonate treatment are poorly understood. Among Danish bisphosphonate users, medium, and long educational levels were associated with lower AFF rates, with medium education remaining associated with lower AFF risk after adjustment, even within a universal healthcare system. Atypical femur fracture (AFF) is a rare but serious fracture type associated with bisphosphonate (BP) treatment. While clinical risk factors are well studied, socioeconomic factors among BP users remain unexplored. We therefore examined whether income and educational level were associated with AFF risk in Denmark. We included all radiologically confirmed AFF cases from 2010 to 2014, identified through blinded reviews of potential AFFs among individuals aged ≥ 50 years, and register-data for a random sample of the general population ≥ 50 (n = 100,253). Health, income, and education data were obtained from Danish national registers. We estimated incidence rates (IR), incidence rate ratios (IRR), and hazard ratios (HR) using Cox regression. Among 164 AFF cases, 116 had BP exposure, and exposure was higher among AFF cases than in the background population (70.7% vs. 7.9%, p < 0.05). The AFF IR among BP users was 32.5 per 10,000 person-years (CI 27.1-39.0). Crude AFF rates differed by income and education, but income was not associated with AFF risk in adjusted Cox regression. BP users with medium or long education had a lower IRR than those with low/missing education (medium: IRR (CI): 0.56 (0.36-0.86); long: IRR (CI): 0.53 (0.28-0.95)). In age- and sex-adjusted Cox analyses, medium education remained associated with a lower AFF risk 0.63 (0.41-0.96). Socioeconomic differences in AFF rates were observed among BP users, but adjusted analyses did not support an independent association between income and AFF risk. Medium education was associated with lower AFF risk after adjustments.
Surfactants, essential chemicals in daily life, are widely utilized across industries, from pharmaceuticals to agriculture, leading to their extensive presence in soils and aquatic environments. Meanwhile, as microbial metabolites, surfactants play a crucial role in enhancing nutrient utilization and promoting the rapid growth of microorganisms. This study aimed to use anionic, nonionic, and cationic surfactants to promote the growth of autotrophic microorganisms and break through the bottleneck of low microbial CO2 fixation efficiency. Among them, only anionic surfactants exhibited significant and universal promoting effects, with a maximum enhancement of 59 %-95 % on autotrophic strains utilizing the Calvin cycle. Furthermore, anionic surfactants, in combination with autotrophic microorganisms, were applied as amendments to improve soil, effectively increasing soil organic carbon content by 27 %-54 %. The long-term effects of these amendments depend on several mechanisms: promoting the Calvin cycle, enhancing soil organic carbon metabolism, facilitating nutrient transport, and reducing the abundance of genes associated with surfactant-degrading enzymes. This study contributes to a deeper understanding of the impacts of surfactants on the environmental CO2 fixation capacity and introduces a novel approach for enhancing soil carbon sink capacity.
Congenital Cytomegalovirus (cCMV) infection is the leading non-genetic cause of sensorineural hearing loss in newborns. Systematic nationwide screening programmes are lacking. Antiviral valganciclovir therapy could improve auditory outcomes if initiated within the first 30 days of life, making timely diagnosis crucial. To address this, we investigated whether a hearing screening-based protocol is suitable. Between 2015 and 2019, newborns, aged ≤21 days, with repeated abnormal newborn hearing screening (NHS) were prospectively enrolled at University Hospital Frankfurt. Oral mucosal swabs were tested for CMV DNA by real-time PCR, with confirmatory urine and blood diagnostics in positive cases. Of 2741 infants presenting for repeat NHS, 2059 (75.1%) showed normal bilateral findings. Of the 682 (24.9%) with abnormal results, 575 (84.3%) were aged >21 days and thus ineligible. A total of 107 infants (3.9%) met both criteria-abnormal NHS and aged ≤21 days-of whom 100 entered per-protocol analysis. Two (2%) were confirmed as cCMV-positive and received valganciclovir. Among the 48 infants who additionally underwent DBS testing, diagnostic sensitivity and specificity were 100%. The presented NHS-driven cCMV protocol reliably identified cCMV-infected newborns to offer timely antiviral therapy. In the absence of universal cCMV screening, this targeted approach offers a challenging but WHO screening-criteria-compliant strategy to enable timely antiviral intervention.
Epilepsy has been attributed to be a most common universal brain neurological disorder afflicting more than 50 million people globally. Neural network is known to be hyperexcitable and hypersynchronous which ultimately result in seizures. Bibliographic databases for peer reviewed journals were searched for key words like epilepsy, seizures, neurological disorders, gut microbiota brain axis, antiepileptic phytomedicines and diagnostic tools. Current review brings forth the putative mechanism to understand the etiological and other vital factors during epileptic seizures and further advancements in the management of the epilepsy along with the role of gut microbiota and herbal medicines in the management of epilepsy. Modern strategies adopted for epilepsy diagnosis and therapeutic treatment methods would certainly pave a way for the neuroscientists to formulate a strategy for comprehensive assessment of epilepsy patients and finding a sustainable cure for the disease through basic and translational research.
Since its inclusion in the Sustainable Development Goals in 2015, the global health target of achieving Universal Health Coverage (UHC) has largely stalled. This article contends that one of the reasons for this lacking progress refers to the fact that the current definition of UHC does not sufficiently account for the transnational realities of global health. This article seeks to develop a more conceptually robust understanding of what UHC is, and what is normatively required to achieve it. In this context, the article proposes a novel definition of UHC that is adapted to the transnational realities of global health and advances an understanding of UHC as a global distributive justice norm. This normative theorising draws on literature in global distributive justice, which has largely been neglected in research and policy-led efforts to understand UHC. In this reconceptualisation, the article accentuates three required discursive shifts: from 'good health' to 'fair health'; from 'assistance' to 'duty'; and from 'cost' to 'investment'. To illustrate the conceptual and empirical validity of this reconceptualisation of UHC, it is then empirically applied to the activities of the Drugs for Neglected Diseases initiative (DNDi) in its health system strengthening efforts on Chagas disease in Latin America.
Crossovers (COs) ensure proper chromosome segregation during meiosis and generate genetic diversity. COs are non-uniformly distributed along chromosomes and almost universally suppressed in centromere-proximal regions, notably creating an important bottleneck for plant breeding. The mechanism of this CO suppression is still not fully understood, but the chromatin state is a contributing factor. Here we identify three factors that actively limit proximal CO in Arabidopsis thaliana: the cohesion establishment factor CTF18, the centromeric cohesin protector SGO2 and the deSUMOylase SPF2. The mutation of these factors allows both the formation of COs in the centromere-proximal region where they were completely absent in the wild type and the enhancement of their frequency where they were rare. COs can be further increased by combining these mutations together or with mutation in the DNA methylase CMT3, suggesting that multiple mechanisms prevent proximal COs in parallel. The identification of the very conserved CTF18, SGO2 and SPF2 as suppressors of centromere-proximal COs highlights the importance of cohesin turnover in this process and opens up new possibilities for plant breeding.
Objectives: To examine the association of contextual school performance, individual educational delay, and socioeconomic conditions with untreated dental caries and tooth loss in Brazilian adolescents. Methods: Data from two nationally representative surveys (SB Brasil, 2010, n = 11,895; 2023, n = 9181 after exclusions). Outcomes were untreated caries and any tooth loss from the DMFT index. Contextual exposure was a Public School Performance Score (PSPS) derived by principal component analysis of school dropout, grade retention, and the Basic Education Development Index. Multilevel logistic models estimated odds ratios (ORs) per 1-unit SD increase in the PSPS for each survey year, adjusting for sex, age, equivalised income, educational delay, municipal income tertiles, and water fluoridation. Results: The PSPS distribution shifted rightwards between surveys (median rose from 0.99 to 2.43), reflecting improvements in IDEB and reductions in dropout and grade retention. In 2010, a 1-SD higher PSPS was associated with significantly lower odds of untreated caries (OR = 0.92, 95%CI 0.84, 0.99) and tooth loss (OR = 0.88, 95%CI 0.81, 0.97). By 2023, the associations had weakened and were no longer statistically significant: caries OR = 0.97 (95%CI 0.86, 1.10); tooth loss OR = 0.95 (95%CI 0.83, 1.08). The year-by-score and cross-level interactions were not statistically significant. Conclusion: The contextual gradient in oral health associated with school performance observed in 2010 was not detectable in 2023, despite overall improvements in educational indicators. Clinical Significance: Even when average school performance rises, additional school-based oral health strategies may be needed to maintain the health gradient, as universal improvements do not automatically translate into reduced inequalities.
Why do some ambitious social health insurance reforms get enacted, while others stall, even within the same country, and under similar structural constraints? This article compares Kenya's failed 2004 National Social Health Insurance Fund Bill, with the reform enacted in 2023. It combines Kingdon's Multiple Streams Approach (MSA) with political economy and populism theory, drawing on 48 elite interviews, and policy documents. Using outcome-explaining process tracing, the study explains why enactment became possible in 2023 but not 2004. MSA highlights how adoption depends on coupling across problem, policy and politics streams. Kenya's case shows that in executive-dominant presidential systems, leaders can also make this coupling happen. Three mechanisms distinguished the 2023 episode: (i) executive dominance and institutional bypass, that compressed procedures and reduced veto points; (ii) elite re-alignment including a fiscal gatekeeper buy-in, which ensured a supportive political settlement; and (iii) populist strategy that moralised inequities, delegitimised opponents and justified expedited enactment. In 2004, the reform faced executive and elite fragmentation, which enabled organised resistance and presidential veto. By integrating MSA with political economy and populism theory, this study conceptualises populism as a coupling mechanism that can align streams by reshaping political feasibility and coalition incentives. Empirically, it provides a rare within-country comparison of health financing reform enactment in an LMIC, clarifying how power, elite bargains, and political strategies shape whether redistributive reforms become law. While these three mechanisms helped ensure the reform's enactment, they risk limiting the reform's ability to increase coverage, specifically for the informal sector populations that it aimed at serving.
Acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), are life-threatening inflammatory syndromes driven by dysregulated pulmonary innate immune responses, with bacterial pneumonia and non-pulmonary sepsis representing the leading etiologies. Despite decades of extensive preclinical and clinical research, no disease-modifying pharmacological therapies have been established for ALI/ARDS, with all-cause mortality remaining persistently between 40% and 60%. The onset and progression of ALI/ARDS are universally accompanied by robust release of the endogenous catecholamines epinephrine (EPI) and norepinephrine (NE), which signal via adrenergic receptors (ARs) expressed on nearly all structural and immune cell populations in the lung. ARs are G protein-coupled receptors (GPCRs) that serve as the core molecular interface between the sympathetic nervous system (SNS) and pulmonary innate immunity, modulating inflammatory responses, barrier integrity, and pathogen clearance within the lung. Recent seminal studies have delineated central neural circuits governing lung inflammation via sympathetic-adrenergic signaling, defined cell subset-specific bidirectional functions of ARs activation, and yielded critical mechanistic insights into the longstanding adrenergic paradox, substantially advancing our neuroimmunological understanding of ALI/ARDS pathogenesis. In this review, we systematically delineate the cell-type-specific and disease context-dependent roles of ARs subtypes in regulating pulmonary innate immune responses in both direct (pneumonia-induced) and indirect (sepsis-induced) ALI/ARDS. We critically integrate the canonical and non-canonical signaling pathways of ARs, and address the longstanding "adrenergic paradox"-the context-dependent bidirectional effects of ARs signaling, which can both suppress excessive inflammation and impair host antibacterial defense. We further examine the translational challenges of ARs-targeted therapies, including the failure of prior clinical trials, and provide a mechanistic framework for the development of optimized therapeutic strategies for ALI/ARDS.
Two-dimensional (2D) macromolecules are atomically thin materials capable of forming crumpled configurations with complex topologies, defining a new paradigm in macromolecular mechanics. Here, we unveil a universal negative size effect, where smaller sheets yield substantially stronger load-bearing capabilities than larger ones. Coarse-grained molecular dynamics simulations demonstrate a negative scaling between compression pressure or modulus and the Föppl-von Kármán number, with the power index determined by crumpling density but independent of material type. Energy analysis indicates that smaller sheets form dense ridge networks with minimal self-folding, enabling efficient load transfer and energy absorption. During densification, a constant ridge-to-vertex increment ratio of 1.5 preserves the superior ridge density of small sheets. Experiments on paper, aluminum foil, polydimethylsiloxane (PDMS), and silicone rubber confirm this behavior across disparate length scales and across material classes. This work reveals the mechanics underlying size-dependent crumpling in 2D macromolecules and provides principles for designing structural metamaterials with tunable load-bearing characteristics.
The early detection of Severe Combined Immunodeficiency (SCID) and X-linked agammaglobulinemia (XLA) prevents fatal outcomes. This study presents the first pilot TREC/KREC newborn screening (NBS) program in southern Kazakhstan, a high-birth-rate region, to establish local reference ranges and assess operational viability. A multiplex real-time PCR assay was used to quantify T-cell (TREC) and kappa-deleting recombination excision circles (KRECs) from dried blood spots of 5000 unselected neonates. Biomarkers were normalized to copies per 106 cells using albumin as a diploid reference gene. Regional 0.5th percentile cut-offs were established (TREC < 3165 copies/106 cells and KREC < 2554 copies/106 cells), and gender and gestational age did not significantly impact biomarker levels. While a low birth weight (≤2500 g) significantly reduced KREC levels, the extreme lower distribution tails remained unaffected, validating the use of universal, unstratified thresholds. Applying these cut-offs yielded an optimal 1.0% initial recall rate. Consistent with global incidence rates, no true positive cases were identified. The established assay and universal percentile cut-offs demonstrate high levels of analytical reliability and demographic stability. This pilot confirms the regional pediatric healthcare infrastructure's readiness for a routine, population-based NBS program without the need for complex algorithms.
Although socioeconomic inequalities in oral health persist despite universal dental care, the role of social determinants remains unclear. Social capital may influence oral frailty, but evidence is limited, particularly regarding individual- and community-level social capital and differences by socioeconomic status (SES). This study examined these associations among community-dwelling older adults. We analyzed longitudinal data from the Japan Gerontological Evaluation Study (JAGES) collected at baseline (2019) and follow-up (2022), including 31,378 older adults. Social capital was assessed across three domains: civic participation, social cohesion, and reciprocity at individual and community levels. Oral frailty was estimated using a validated predictive model incorporating age, remaining teeth, chewing ability, and swallowing function. Multivariable logistic regression analyses examined associations between individual- and community-level social capital and oral frailty risk, as well as the interaction effects of social capital, stratified by SES, on oral frailty risk across SES groups. All models were adjusted for potential confounders, including sex, age, education, household composition, and chronic conditions. Over three years, 21.6% of participants developed oral frailty risk, with a higher incidence among low-SES participants (24.6%) than among high-SES participants (19.9%). At the higher individual level, higher health-related social capital and social cohesion were significantly associated with lower odds of oral frailty risk across SES groups. Higher civic participation was also associated with lower oral frailty risk across SES groups, with a stronger association observed among low-SES participants. At the community level, higher civic participation was associated with lower oral frailty risk in the overall sample and among low-SES participants. A significant interaction between SES and individual-level civic participation was observed, while no significant interactions were found for other social capital measures. Individual-level health-related social capital was associated with a lower risk of oral frailty among older adults. Furthermore, the inverse association between civic participation and oral frailty was stronger among individuals with low socioeconomic status, suggesting that promoting social participation may be a promising strategy for reducing socioeconomic inequalities in oral frailty.
Sustainable head and neck cancer (HNC) surgery is challenged by environmental impact, workforce shortages, inequitable access to advanced techniques, and policy constraints. Addressing these areas is critical for equitable, high-quality care. This structured narrative review synthesizes evidence on environmental sustainability, workforce development, technological innovation, health policy, and socioeconomic determinants in HNC surgery, without aiming to provide a systematic or exhaustive evidence synthesis. Sources included peer-reviewed literature, global workforce surveys, and international policy reports, with a focus on disparities between high-income countries (HICs) and low- and middle-income countries (LMICs). Operating rooms produce up to 70% of hospital solid waste and consume 3-6 times more energy than other units; reusable instruments and improved waste segregation can reduce carbon footprints by over 50%. Workforce shortages are severe in LMICs, where subspecialty training is scarce; global partnerships, bidirectional education, and simulation-based learning can expand local capacity. Telemedicine, artificial intelligence, and three-dimensional printing enhance surgical planning, training, and access but may widen disparities without equitable deployment. Policy tools-including diagnosis-related groups, bundled payments, and universal coverage-affect access and innovation uptake. Pandemic preparedness underscores the value of resilient systems with flexible staffing and telehealth integration. HNC surgery requires coordinated action across environmental, workforce, technological, socioeconomic, and policy domains; however, future systematic reviews are needed to comprehensively map the evidence base and assess its methodological quality. Embedding sustainability in clinical practice, ensuring equitable innovation access, and aligning reimbursement with high-value care can strengthen system resilience, improve outcomes, and support long-term surgical service viability.
This study aims to investigate the accuracy and precision of an optical measurement method based on backlight video analysis for measuring gap distances between tendon stumps in a rigid tendon model. A rigid 3D-printed tendon model was sutured and subjected to traction using a universal mechanical testing machine. The gap between stumps was filmed in frontal and lateral planes with backlight illumination and a simple mirror system. A custom software program calculated gap distances from the recorded videos and the optical measurements were compared with mechanical testing machine measurements to assess precision and accuracy. The mean difference (bias) in the frontal plane was -0.01 mm (SD: 0.01 mm) and in the lateral plane was 0.04 mm (SD: 0.03 mm). Bland-Altman analysis showed limits of agreement (LoA) of 0.04 mm in the frontal plane and 0.06 mm in the lateral plane. Measurements between planes showed a very strong correlation with a Spearman's rho correlation test of 1.000 (p<0.001). The optical method showed errors on the order of hundredths of a millimeter and proved to be both precise and accurate, validating a new method for gap measurement in biomechanical tendon studies. Level of Evidence IV; Experimental Validation Study. Este estudo tem como objetivo investigar a acurácia e a precisão de um método de mensuração óptica baseado na análise de vídeo com retroiluminação para medir as distâncias do afastamento entre cotos tendíneos em um modelo tendíneo rígido. Um modelo tendíneo rígido impresso em 3D foi suturado e submetido à tração em uma máquina universal de ensaios mecânicos. O espaço entre os cotos foi filmado nos planos frontal e lateral com retroiluminação e um sistema simples de espelho. Um software personalizado calculou as distâncias do espaço a partir dos vídeos gravados, e as mensurações ópticas foram comparadas com as mensurações da máquina de ensaios mecânicos para avaliar a precisão e a acurácia. A diferença média, ou viés, no plano frontal foi de -0,01 mm (DP: 0,01 mm) e, no plano lateral, de 0,04 mm (DP: 0,03 mm). A análise de Bland-Altman apresentou limites de concordância (LoA) de 0,04 mm no plano frontal e de 0,06 mm no plano lateral. As mensurações entre os planos apresentaram correlação muito forte, com coeficiente rho de Spearman de 1,000 (p<0,001). O método óptico apresentou erros da ordem de centésimos de milímetro e demonstrou ser preciso e acurado, validando um novo método para mensuração do espaço em estudos biomecânicos de tendões. Nível de Evidência IV; Estudo de Validação Experimental.