High Volume Research Articles

Soil-aggregate-cement mixtures for base pavement layers: A strength and stiffness characterization

Pavements subjected to high volume load require a robust structure. In Brazil, cemented base layer is usually used instead of asphalt concrete thick layer due to cost issues. Soil-aggregate-cement (SAC) mixture is an alternative in pavement application, but the lack of design and dosage protocols hinders the understanding of the parameters influencing its mechanical behavior. This study presents a mechanical characterization of SAC mixtures in terms of strength (UCS and ITS) and stiffness (Mr), focusing on integrating the needs of pavement design to dosage purposes. For this, different SAC mixtures are produced, varying the soil-aggregate proportion (30:70 and 20:80) and cement content (3, 5 and 7 %). Mechanical properties were measured on cured mixtures at 0, 7 and 28 days and compared to structural responses of hypothetical pavements computed by mechanistic analysis. The results indicate a potential for using SAC mixtures in base layers due to their higher strength and stiffness. Predictive models relating ITS x UCS, Mr x UCS, and Mr x ITS with good statistical fit were proposed to assist researchers and engineers in selecting mixtures more adequate and durable for pavement applications, based on the concept of limiting the tensile stress acting on the cemented base course.

New Insights Into Hepatic Impairment (HI) Trials.

Hepatic impairment (HI) trials are traditionally part of the clinical pharmacology development to assess the need for dose adaptation in people with impaired metabolic capacity due to their diseased liver. This review aimed at looking into the data from dedicated HI studies, cluster these data into various categories and connect the effect by HI with reported pharmacokinetics (PK) properties in order to identify patterns that may allow waiver, extrapolations, or adapted HI study designs. Based on a ratio ≥ 2 or ≤ 0.5 in AUC or Cmax between hepatically impaired participants/healthy controls these were considered "positive" or "negative". In case of more than one HI severity stratum per compound included in the HI trial, the comparison of the AUC ratios for mild, moderate, or severe HI were used to investigate the increase across HI categories. For the in total 436 hits, relevant PK information could be retrieved for 273 compounds of which 199 were categorized negative, 69 positive ups and 5 positive downs. Fourteen out of 69 compounds demonstrated a steep increase in the AUC ratios from mild to severe HI. Compounds demonstrating a steep increase typically had a high plasma protein binding of > 95%, high volume of distribution, lower absolute bioavailability, minor elimination via the kidneys, were predominantly metabolized by CYP3A4 or CYP2D6 and the majority of these compounds were substrates of OATP1B1. While for compounds with steep increase studies in all severity strata may be warranted they may also offer the potential to estimate the appropriate doses in an HI trial. On the other hand, for compounds with slow or no increase across HI severity strata, reduced HI trials may be justified, e.g. only testing PK in moderate HI.

Commercial kitchen operations produce a diverse range of gas-phase reactive nitrogen species.

Gas-phase reactive nitrogen species (Nr) are important drivers of indoor air quality. Cooking and cleaning are significant direct sources indoors, whose emissions will vary depending on activity and materials used. Commercial kitchens experience regular high volumes of both cooking and cleaning, making them ideal study locations for exploring emission factors from these sources. Here, we present a total Nr (tNr) budget and contributions of key species NO, NO2, acidic Nr (primarily HONO) and basic Nr (primarily NH3) using novel instrumentation in a commercial kitchen over a two-week period. In general, highest tNr was observed in the morning and driven compositionally by NO, indicative of cooking events in the kitchen. The observed HONO and basic Nr levels were unexpectedly stable throughout the day, despite the dynamic and high air change rate in the kitchen. After summing the measured NOx, HONO and Nr,base fractions, there was on average 5 ppbv of Nr unaccounted for, expected to be dominated by neutral Nr species. Using co-located measurements from a proton transfer reaction mass spectrometer (PTR-MS), we propose the identities for these major Nr species from cooking and cleaning that contributed to Nr,base and the neutral fraction of tNr. When focused specifically on cooking events in the kitchen, a vast array of N-containing species was observed by the PTR-MS. Reproducibly, oxygenated N-containing class ions (C1-12H3-24O1-4N1-3), consistent with the known formulae of amides, were observed during meat cooking and may be good cooking tracers. During cleaning, an unexpectedly high level of chloramines was observed, with monochloramine dominating the profile, as emitted directly from HOCl based cleaners or through surface reactions with reduced-N species. For many species within the tNr budget, including HONO, acetonitrile and basic Nr species, we observed stable levels day and night despite the high air change rate during the day (>27 h-1). The stable levels for these species point to large surface reservoirs which act as a significant indoor source, that will be transported outdoors with ventilation.

Plastic additives affect estrogenic pathways and lipid metabolism in precision - cut - liver slices in Atlantic cod (Gadus morhua).

The overall aim of the present study was to determine if exposure to three high volume plastic additives, including diethylhexyl phthalate (DEHP), bisphenol A (BPA) and benzotriazoles (BT), have the potential to promote adverse effects in Atlantic cod (G. morhua). Ex vivo precision cut - liver slices (PCLS) from six male juvenile Atlantic cod were exposed to four concentrations of mono-(2-ethylhexyl)-phthalate (MEHP, the main metabolite of DEHP), BPA and BT both singly and in mixtures ranging from 0.1 to 100μM (MEHP), 0.022-22μM (BPA) and 0.042-42μM (BT). Histology and transmission electron microscopy (TEM) were used to assess pathological changes and ultrastructure of the exposed liver tissue. Vitellogenin (Vtg) produced by the hepatic tissue was analyzed using ELISA, and the transcription levels of selected biomarker genes (vtg1, esr1, cyp1a, scdb, aclya, fabp1a, acox1, hnf4a and cebp) were measured using Quantitative real-time polymerase chain reaction (Q-PCR). An estrogenic effect was observed with a significant upregulation of the vtg1 and esr1 genes and increase in Vtg protein synthesis following exposure to BPA and a mixture of the selected compounds. The hnf4a showed a significant downregulation following mixture exposure, where the BPA was suspected to be the main driver for this response although not inducing a significant downregulation in the single component exposure. There was no significant difference between the mixture exposure and the individual compound exposures, nevertheless a tendency of an antagonistic mixture effect for the biomarkers of estrogenic effect (vtg1, esr1 and Vtg), and possibly synergistic or additive effect on the lipid metabolism related gene hnf4a, warrants further investigation.

Development of Water-Cured Alkali-Activated Concrete with a High Volume of Silica-Rich Waste Limestone Powder and GGBS and Fly Ash Materials: Strength, Durability, and Life Cycle Assessment

Development of Water-Cured Alkali-Activated Concrete with a High Volume of Silica-Rich Waste Limestone Powder and GGBS and Fly Ash Materials: Strength, Durability, and Life Cycle Assessment

Potential use of high-volume of slag in pervious concrete: technical assessment and sustainability analysis

ABSTRACT Large porosity and interconnected pore structure allow pervious concrete to find interesting applications in urban pavement. At the same time, accounting for the exorbitant greenhouse gas emissions associated with Portland cement production, the application of supplementary cementitious materials (SCMs) in pervious concrete has received significant attention in studies. This research investigates the feasibility of developing pervious concrete by substituting a high volume of Portland cement with slag. Different mixtures were made to investigate the effects of high-volume slag content (60% and 80%), fine aggregate incorporation (10% and 15%) and combined use of SCMs (high-volume slag + silica fume) in pervious concrete. Concretes were tested for void content, compressive strength, permeability and abrasion resistance. Based on the results, although the compressive strength of pervious concrete was decreased by the inclusion of high-volume slag, it can be compensated to some extent by increasing the curing age. Furthermore, by decreasing the material cost and CO2 emissions up to 8.2% and 61.2% over plain pervious concrete, respectively, utilisation of high-volume slag can produce relatively more cost-effective and eco-friendly pervious concrete. In general, combined use of slag + silica fume or incorporation of fine aggregate at the optimum replacement ratio can be suggested to obtain higher strength and acceptable permeability in high-volume slag pervious concrete.

Analysis on Management Strategies and Digital Transformations with the Help of Web Tracking Tools at DTDC, Bangalore

This study examines how DTDC, a leading logistics and courier company, has utilized web tracking tools to implement digital transformation strategies. The paper explores the integration of management strategies with cutting-edge digital tools to enhance operational efficiency, customer satisfaction, and decision-making. By analysing the role of web tracking systems, this paper sheds light on their impact on organizational agility, data-driven culture, and market competitiveness. The evaluation of digital transformers with web tracking practices are crucial due to the city's role as a major commercial hub in India, characterized by high volume shipping demands and complex logistics networks. Web tracking strategies in this region are imperative for maintaining timely delivery schedules, optimizing inventory turnover, and minimizing operational costs. This study delves into the various aspects of chi square tools examining how strategies such as layout optimization, technological integration, workforce management, and supply chain coordination contribute to enhancing organizational efficiency. Keywords: Digital Transformation, Web Tracking Tools, Management Strategies, DTDC Logistics, Operational Efficiency, Customer Experience, Data Analytics.

Effect of linear low density plyethylene on the physico‐mechanical properties of multiphase space domestic waste composites prepared by hot pressing

AbstractTypical space domestic waste (SWL‐10%, SWL‐25%, SWL‐40%, SWL‐50%) added with different proportions of linear low density polyethylene (LLDPE) was used as raw material to prepare high‐stability composite materials by heating and compression molding. The hot pressing of LLDPE and space waste not only effectively reduces volume, but also yields composite material with superior physical and mechanical properties. This study investigated the impact of hot pressing process on the stability of composites prepared from multiphase space domestic waste. The physical and mechanical properties of these compressed blocks were analyzed, while scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the composites' properties. Our results demonstrate that BSWL‐40% (hot pressing temperature (160 °C), LLDPE addition ratio (50%)) composite achieves a volume reduction rate as high as 96%, with an initial density increase by 16.1%. Furthermore, the compressive strength and impact strength of BSWL‐50% composites increased by 19% (6.85 MPa) and 71% (14.3 KJ/m2). These improvements can be attributed to enhanced physical/mechanical interlocking structure at a temperature of 160 °C based on SEM analysis findings. Fourier transmission infrared spectroscopy also confirmed the presence of ester bonds between LLDPE and space domestic waste materials.Highlights Solid‐plastic composites were successfully prepared by hot pressing. LLDPE particles were added to domestic waste for composite fabrication. The BSWL‐40% composite achieved a high volume reduction of 96%. The stability of the composite was judged by physical and mechanical properties. The BSWL‐50% composite exhibited superior mechanical properties.

Single-Cell Analysis in Cerebrovascular Research: Primed for Breakthroughs and Clinical Impact.

Data generated using single-cell RNA-sequencing has the potential to transform understanding of the cerebral circulation and advance clinical care. However, the high volume of data, sometimes generated and presented without proper pathophysiological context, can be difficult to interpret and integrate into current understanding of the cerebral circulation and its disorders. Furthermore, heterogeneity in the representation of brain regions and vascular segments makes it difficult to compare results across studies. There are currently no standards for tissue collection and processing that allow easy comparisons across studies and analytical platforms. There are no standards either for single-cell data analysis and presentation. This topical review introduces single-cell RNA-sequencing to physicians and scientists in the cerebrovascular field, with the goals of highlighting opportunities and challenges of applying this technology in the cerebrovascular field and discussing key concepts and knowledge gaps that can be addressed by single-cell RNA-sequencing.

The Use of Artificial Intelligence in Aviation: A Bibliometric Analysis

The bibliometric analysis of 395 articles selected from the Web of Science (WoS) database between 2004 and 2024 is designed to provide a foundation for future research by mapping scientific collaborations, conceptual clusters, citation relationships, and intellectual structures in the research area, highlighting the international scope of the research area, and identifying emerging trends and influential studies. The results show that dominant topics such as machine learning, deep learning, aviation safety, atmospheric modeling, and anomaly detection are being studied in academia, highlighting the central role of AI in improving aviation safety and operational efficiency. High-impact journals such asIEEE Access and Aerospace have emerged as leading platforms, while Transportation Research Part C and the Journal of Air Transport Management are prominent in logistics and aviation-focused research. China and the United States lead aerospace and AI research with high publication volumes and significant impact. Italy contributes fewer publications but makes a notable impact, while the United Kingdom plays an important role in this field with active research efforts. Institutions such as Nanjing University of Aeronautics, Astronautics, and Vanderbilt University play an important role in advancing the field. These data show that, on both a journal and country basis, certain centers and countries have assumed dominant roles in the global research agenda in aerospace and AI, which have directly contributed to the formation of the aerospace ecosystem. These results provide important clues as to where future research will focus, and show that research communities are increasingly collaborating.

Androgen receptor pathway inhibitors vs. docetaxel chemotherapy for metastatic hormone-sensitive and first-line castration resistant prostate cancer

PurposeNo currently available phase III trial compared docetaxel vs. androgen receptor pathway inhibitors (ARPI) regarding cancer-control outcomes in metastatic hormone-sensitive prostate cancer (mHSPC). Moreover, few is known about the effect of sequential therapies in mHSPC and subsequent metastatic castration resistant prostate cancer (mCRPC).MethodsWe relied on the FRAMCAP database and compared docetaxel vs. ARPI in mHSPC patients regarding time to mCRPC (ttCRPC) and overall survival (OS). Sensitivity analyses addressed high volume mHSPC patients. Finally, sequential therapies were compared regarding progression-free survival (PFS) and OS in first-line mCRPC.ResultsOf 419 included mHSPC patients, 25% received docetaxel vs. 75% ARPI. ARPI patients were significantly older (71 vs. 66 years), and harbored lower baseline PSA (38 vs. 183 ng/ml, both p ≤ 0.002). Median ttCRPC was significantly longer for ARPI than for docetaxel-treated patients (30 vs. 17 months, hazard ratio [HR]: 0.49, p < 0.001). In OS analyses, ARPI patients also exhibited significantly longer OS, relative to docetaxel patients (96 vs. 50 months, HR: 0.67, p = 0.03). After multivariable adjustment in Cox regression models, no difference between both treatments remained in both analyses (all p > 0.05). In sensitivity analyses of high volume mHSPC patients only, also no ttCRPC or OS differences were observed for ARPI vs. docetaxel (all p > 0.05). Regarding sequential therapies, no PFS and OS differences were observed for all and specifically high volume mHSPC patients, when ARPI-ARPI vs. ARPI-docetaxel vs. docetaxel-ARPI treatments were compared (all p > 0.05).ConclusionIn real-world setting, ARPI treatment performs comparable to docetaxel chemotherapy in mHSPC. Therefore, docetaxel should only be used in triplet therapy. Moreover, no differences for sequential therapies of ARPI/docetaxel combinations in first-line mCRPC were observed.

Laparoscopic Reversal of Roux-en-Y Gastric Bypass with Hand-Sewn Gastro-Gastrostomy and Resection of the Alimentary Limb.

Roux-en-Y gastric bypass (RYGB) reversal might be necessary to alleviate refractory surgical or nutritional complications, such as postprandial hypoglycemia, malnutrition, marginal ulceration, malabsorption, chronic diarrhea, nausea and vomiting, gastro-esophageal reflux disease, chronic pain, or excessive weight loss. The surgical technique of RYGB reversal is not standardized; potential strategies include the following: (1) gastro-gastrostomy: hand-sewn technique, linear stapler, circular stapler; (2) handling of the Roux limb: reconnection or resection (if remaining intestinal length ≥ 4 m). We demonstrate the surgical technique of a laparoscopic reversal of RYGB with hand-sewn gastro-gastrostomy and resection of the alimentary limb with the aim of improving the patient's quality of life. The gastric pouch is horizontally divided proximal to the previous staple line. A hand-sewn end to end anastomosis is created between the distal gastric pouch and the horizontal part of the gastric remnant adjacent to the lesser curve. The posterior wall is sutured in two layers. The anterior layer is closed with continuous 3-0 PDS full-thickness stitches over a 36-French oro-gastric calibration bougie. After evaluation of intestinal limbs and ruling out of hernial defects, the alimentary limb is divided just above the jejuno-jejunal Roux-anastomosis and is resected. Reversal of RYGB is a precious treatment option for otherwise unmanageable postbariatric complications in well-selected cases. The operation should be performed in high volume bariatric centers after multidisciplinary patient preparation. The early and late complications of the reversal are higher than the rates seen in primary MBS; therefore, patients should be informed and monitored accordingly to ensure the best achievable outcomes.

Urban traffic accidents in Isfahan city: a study of prehospital response time intervals

IntroductionTraffic accidents are a major public health concern worldwide, resulting in significant injuries, fatalities, and economic costs. In urban zones, traffic accident dynamics can vary significantly due to population density, infrastructure, and emergency response capabilities. The present study was conducted to determine the time intervals of prehospital emergencies in traffic accidents by separating the 15 zones of Isfahan city, Iran.MethodsThis descriptive study was conducted in 2023. The sampling approach involved a census that included all prehospital emergency missions that occurred in the second half of 2022. A total of 7613 missions were examined. To collect the data, a checklist covering demographic characteristics and mission-specific features was utilized. The information was recorded in an Excel spreadsheet and described via the prehospital emergency information system.ResultsAfter analyzing 7,613 urban missions, it was determined that Zone 12 had the highest number of prehospital emergency missions in all three time periods: morning, afternoon, and evening. Therefore, all the times (reaction time, response time, scene time, transfer time, and hospitalization time) were in accordance with prehospital emergency time standards in Iran.ConclusionOn the basis of the findings of this study, it is crucial to identify zones with greater population movement, highways, or high traffic volume and establish bases in suitable locations whenever feasible. Additionally, in zones with a greater number of missions, there should be an appropriate number of ambulances in proportion to the mission volume.

EVALUATION OF THE ANIONIC POLYMER ADDITION IN THE CLARIFICATION OF REAL EFFLUENT FROM THE HYDROPHILIC COTTON BLEACHING

Water, essential for maintaining life, is widely used in industrial processes, generating high volumes of industrial liquid effluents. These, if not treated properly end up contaminating water bodies and causing serious damage to the environment. Among the technologies applied to industrial effluent treatment, physical-chemical treatments are usually accompanied by auxiliary products. In this context, the present work aimed to evaluate the influence of anionic polyacrylamide addition as a coagulation aid of industrial effluent clarification from the bleaching process of cotton hydrophilic. Based on preliminary assays, a Central Rotational Composite Design (DCCR) was developed for the coagulant/flocculant combination, evaluating pH, turbidity, and color. The results obtained showed that anionic polymer improved the treatment performance, forming larger, heavier, and more stable flakes, which resulted in better removal of turbidity (29.7%) and color (33.09%) when compared to the treatment without its addition (22% and 25%) respectively. They also speed up the decanting process, reducing the consumption of primary coagulant and contributing to the effluent parameters being following the discharge standards stipulated by legislation, proving its efficiency as a coagulation aid.

Preparation and Performance Optimization of High Times Volume Expandable Graphite Gel Material for Mining Use

Preparation and Performance Optimization of High Times Volume Expandable Graphite Gel Material for Mining Use

Biochar Adsorption: A Green Approach to PFAS Contaminant Removal

ABSTRACTThe widespread use of PFAS in nonstick cookware, hydrophobic textiles, stain‐resistant fabrics, cosmetics, and floor coverings has led to their persistent presence in wastewater streams, posing significant human health and ecological risks. Exposure to PFAS is linked to adverse reproductive outcomes and elevated blood pressure in pregnant individuals, and it negatively impacts aquatic ecosystems, particularly algal populations and microbial communities. This evaluation focuses on biochar's efficacy and cost‐efficiency in removing PFAS from water, highlighting its potential as a sustainable remediation method. Biochar's high microporous volumes (0.1–1.0 cm³/g), aromaticity, and surface oxygen‐containing functional groups make it effective for PFAS adsorption. Various biochar production methods, such as pyrolysis of biomass waste, and innovative modification techniques like acid treatment, ball milling, and metal nanoparticle incorporation are explored to enhance PFAS adsorption capacity. The mechanisms, kinetics, and thermodynamics of PFAS adsorption onto biochar are examined, providing insights into molecular‐level interactions and adsorption isotherms. Furthermore, machine learning models are utilized to understand the impact of processing parameters on PFAS removal efficiency. The review also presents toxicological studies on the harmful effects of PFAS exposure on organisms and humans, emphasizing the urgent need for effective remediation strategies. Ultimately, the potential of biochar‐based approaches in treating PFAS‐contaminated water is underscored by optimizing its physicochemical properties through innovative production and modification methods, along with predictive modeling of adsorption behavior.

Improving Cancer Diagnosis in Alberta, Canada: A Qualitative Study of Emergency Department Healthcare Providers’ Perspectives on Diagnosing Cancer in the Emergency Setting

Cancer is the leading cause of death in Canada, with diagnoses increasing annually. In Alberta, many cancer cases are detected in emergency departments, often at advanced stages. Despite the significant role of emergency departments in cancer diagnosis, limited research exists on the experiences of healthcare providers in this context. This qualitative study aimed to explore the perspectives of physicians and nurses working in emergency departments in Edmonton and Calgary regarding cancer diagnosis. Semi-structured interviews were conducted with 17 physicians and nurses, recruited through convenience and snowball sampling. Data collection continued until thematic saturation was reached. Interviews were analyzed thematically using an inductive, iterative process. Three main themes emerged: the acute care focus of the emergency department, its unsuitability for cancer diagnosis, and the need for systemic improvements to better support patients with suspected cancer. Participants highlighted challenges related to high patient volumes, the emotional burden of delivering cancer diagnoses, and barriers to effective communication and patient interaction in a fast-paced, high-pressure environment. The findings suggest the need for systemic reforms, including stronger primary care and improved care coordination, to alleviate pressure on emergency departments and enhance both patient outcomes and healthcare provider well-being.

Enhancing mass vaccination programs with queueing theory and spatial optimization.

Mass vaccination is a cornerstone of public health emergency preparedness and response. However, injudicious placement of vaccination sites can lead to the formation of long waiting lines or queues, which discourages individuals from waiting to be vaccinated and may thus jeopardize the achievement of public health targets. Queueing theory offers a framework for modeling queue formation at vaccination sites and its effect on vaccine uptake. We developed an algorithm that integrates queueing theory within a spatial optimization framework to optimize the placement of mass vaccination sites. The algorithm was built and tested using data from a mass dog rabies vaccination campaign in Arequipa, Peru. We compared expected vaccination coverage and losses from queueing (i.e., attrition) for sites optimized with our queue-conscious algorithm to those used in a previous vaccination campaign, as well as to sites obtained from a queue-naïve version of the same algorithm. Sites placed by the queue-conscious algorithm resulted in 9-32% less attrition and 11-12% higher vaccination coverage compared to previously used sites and 9-19% less attrition and 1-2% higher vaccination coverage compared to sites placed by the queue-naïve algorithm. Compared to the queue-naïve algorithm, the queue-conscious algorithm placed more sites in densely populated areas to offset high arrival volumes, thereby reducing losses due to excessive queueing. These results were not sensitive to misspecification of queueing parameters or relaxation of the constant arrival rate assumption. One should consider losses from queueing to optimally place mass vaccination sites, even when empirically derived queueing parameters are not available. Due to the negative impacts of excessive wait times on participant satisfaction, reducing queueing attrition is also expected to yield downstream benefits and improve vaccination coverage in subsequent mass vaccination campaigns.

Highly Efficient Removal of Cr(VI) by Biochar Derived from Vietnamese Young Durian Fruit: Comparison of Traditional and Microwave-Assisted Pyrolysis.

This study compares the material characteristics and evaluates the Cr(VI) adsorption capacity of biochar derived from a novel byproduct (young durian fruit, YDF), synthesized using two pyrolysis methods (traditional and microwave-assisted). The optimal pyrolysis conditions for porosity were 800 °C and 800 W for 30 min, respectively. The traditional pyrolysis method yielded a very high surface area and pore volume (668 m2/g; 0.332 cm3/g). XRD patterns and FTIR spectra demonstrated structural and functional group differences, significantly impacting the Cr(VI) removal efficiency in water. pH was a critical factor with optimal adsorption at pH 2.0. The adsorption process reached equilibrium at 180 and 100 min at initial concentrations of 100 and 125 mg/L for biochar synthesized by traditional and microwave-assisted pyrolysis, respectively. The adsorption mechanisms proposed based on modern analytical methods include adsorption-reduction, ion exchange, electrostatic interaction, and surface complexation. Industrial wastewater containing chromium was effectively treated under natural conditions (pH = 5.88; Co = 129.9 mg/L) using biochar synthesized via microwave, achieving a Qe of 21.41 mg/g. The research results pave the way for new directions in the synthesis and application of biochar in environmental treatment, specifically using young fruit materials and microwave methods.

Individual-, Hospital-, and Community-Level Factors Associated with Sudden Unexpected Infant Death Among Infants Born Preterm in 5 US States.

To investigate individual-, hospital-, and community-level factors associated with sudden unexpected infant death (SUID) among infants born preterm. The following linked dataset from 5 states (California, Michigan, Oregon, Pennsylvania, and South Carolina) from 2005 through 2020 was used: (1) infant birth and death certificates; (2) maternal and infant birth hospitalization discharge records; (3) birthing hospital data from the American Hospital Association; and (4) community-level data from the Social Vulnerability Index (SVI).) Multivariable models were used to assess the independent association between these multilevel factors and SUID, adjusting for several maternal and infant characteristics. Overall, we found that maternal demographic factors (race and ethnicity, education, insurance) and infant gestational age were significant predictors of SUID. There was no difference in SUID odds by state, urban influence code, and maternal complications of pregnancy. Compared with mothers who lived in areas with the lowest SVI, those who resided in the highest SVI were more likely to experience SUID. There was no difference in SUID odds between infants who did or did not experience one or more complications of prematurity. For hospital-level factors, there was no difference in SUID odds among infants cared for in teaching vs nonteaching hospitals or in low vs high volume preterm birth hospitals. Individual- and community-level factors were associated with SUID among infants born preterm. The neonatal intensive care unit hospitalization may provide a critical window of opportunity to engage families about SUID-risk reducing practices.