Encounter Rates Research Articles

Comorbid depression and anxiety and their association with health care resource utilization among individuals with type 1 diabetes in the United States.

Type 1 diabetes mellitus (T1DM) is a prevalent chronic endocrine disorder and accounts for 5%-10% of all diabetes cases worldwide. T1DM can have a substantial impact on health care utilization. Although it is well known that individuals with diabetes are at a greater risk of mental health disorders, specific evidence addressing the health care burden of comorbid depression/anxiety in people affected by T1DM is lacking. To assess health care resource utilization (HCRU) among adults with T1DM and comorbid depression or anxiety. We identified individuals aged 18 to 64 with a T1DM diagnosis from January 1, 2017, to December 31, 2021, using a 25% random sample of the IQVIA PharMetrics Plus for Academics database. The index date was the date of the first medical claim with a T1DM diagnosis. Eligibility required continuous medical and prescription coverage for 12 months before (baseline) and after (follow-up) the index date. Comorbid depression/anxiety and baseline characteristics were assessed during the baseline period. The following 2 mutually exclusive groups were created: individuals with T1DM and comorbid depression/anxiety, and those with only T1DM. To balance baseline demographic and clinical characteristics between the groups, we implemented 1:1 propensity-score matching. We assessed all-cause, diabetes-related, and major adverse cardiovascular event-related HCRU during the follow-up period. Logistic (binary) and negative binomial (count) regression models examined the association between comorbid depression/anxiety and HCRU across types of health care settings. Out of 6,491 eligible individuals with T1DM, 1,168 (18%) had either depression or anxiety. In the matched cohort of 2,314 individuals, those with T1DM and comorbid depression/anxiety had significantly higher odds of all-cause emergency department visits (odds ratio = 1.67; 95% CI = 1.39-2.00) and higher rates of physician office visits (incidence rate ratio = 1.37; 95% CI = 1.27-1.47) and other outpatient encounters (incidence rate ratio = 1.23; 95% CI = 1.13-1.34) than those with only T1DM. Findings were similar for diabetes-related and major adverse cardiovascular event-related HCRU. Comorbid depression/anxiety among individuals with T1DM results in significantly higher HCRU than T1DM alone. The findings underscore the importance of effective management of comorbid depression/anxiety in the T1DM population.

Trends in Medical Encounters Involving Cannabis-Related Disorders Among US Medicare Beneficiaries, 2017-2022.

Objectives. To characterize cannabis-related disorder medical encounter trends in the US Medicare population during 2017 to 2022. Methods. We conducted a descriptive study, which included 56 624 432 beneficiaries aged 65 years or older and 10 247 953 aged 18 to 64 years with disability. All were continuously enrolled in Medicare (Fee-for-Service or Advantage) for 183 or more days before the first day of the calendar year. We identified cannabis-related disorder encounters using International Classification of Diseases, 10th Revision, Clinical Modification diagnosis codes and computed annual encounter rates per 10 000 beneficiaries. We used the Mann-Kendall test to analyze trends over time. Results. Annual cannabis-related disorder encounter trends among beneficiaries aged 65 years or older ranged from 15.9 (95% confidence interval [CI] = 15.8, 16.0) to 39.3 (95% CI = 39.1, 39.5) per 10 000. Rates among beneficiaries aged 18 to 64 years with disability ranged from 274.8 (95% CI = 273.6, 276.0) to 373.7 (95% CI = 372.3, 375.2) per 10 000. Rates increased over time across both groups, with average annual increases of 4.3 (95% CI = 3.3, 5.3; P = .01) and 17.1 (95% CI = 11.0, 23.2; P = .02) per 10 000, respectively. Conclusions. Further work is needed to explore the impact of coexisting medical conditions on outcomes that result from cannabis-related disorders. (Am J Public Health. 2024;114(S8):S694-S697. https://doi.org/10.2105/AJPH.2024.307729).

Trends in Urinary Tract Infection Management in Women.

Urinary tract infections (UTIs) are a common cause of health care utilization in the United States. The coronavirus disease 2019 (COVID-19) pandemic accelerated virtual care for UTIs. This retrospective cohort study analyzes more than 1.2 million encounters for UTI based on diagnosis codes, examining temporal trends focusing on virtual compared with in-person encounters, antibiotic dispensation rates, and culture-confirmed UTIs. From 2015 to 2022, UTI encounters increased by 325.9%, with a majority occurring at virtual visits. The rate of UTI encounters per 1,000 adult female patients increased by 241.6%. Antibiotic dispensation rates increased, surpassing the rise in rate of positive urine cultures, suggesting increasing use of empiric antibiotics. Our findings underscore the importance of balancing telemedicine's accessibility with maintaining antibiotic stewardship and highlight the need for updated guidelines.

Running with the bulls

Context. Stars and planets form in regions of enhanced stellar density, subjecting protoplanetary discs to gravitational perturbations from neighbouring stars. Observations in the Taurus star-forming region have uncovered evidence of at least three recent, star-disc encounters that have truncated discs (HV/DO Tau, RW Aurigae, and UX Tau), raising questions about the frequency of such events. Aims. We aim to assess the probability of observing truncating star-disc encounters in Taurus. Methods. We generated a physically motivated dynamical model including binaries and a spatial-kinematic substructure to follow the historical dynamical evolution of the Taurus star-forming region. We used this model to track star-disc encounters and the resulting outer disc truncation over the lifetime of Taurus. Results. A quarter of discs are truncated below 30 au by dynamical encounters, but this truncation mostly occurs in binaries over the course of a few orbital periods, on a timescale ≲0.1 Myr. Nonetheless, some truncating encounters still occur up to the present age of Taurus. Strongly truncating encounters (ejecting ≳10 percent of the disc mass) occur at a rate ∼10 Myr−1, sufficient to explain the encounter between HV and DO Tau ∼0.1 Myr ago. If encounters that eject only ∼1 percent of the disc mass are responsible for RW Aurigae and UX Tau, then they are also expected with encounter rate Γenc ∼ 100–200 Myr−1. However, the observed sample of recent encounters is probably incomplete, since these examples occurred in systems that are not consistent with a random drawing from the mass function. One more observed example would statistically imply additional physics, such as replenishment of the outer disc material. Conclusions. The marginal consistency of the frequency of observed recent star-disc encounters with theoretical expectations underlines the value of future large surveys searching for external structures associated with recent encounters. The outcome of such a survey offers a highly constraining, novel probe of protoplanetary disc physics.

Differential relative catchability of wild‐ and hatchery‐origin steelhead in the Deschutes River, Oregon

AbstractObjectiveWe assessed the relative proportions of wild‐ and hatchery‐origin summer steelhead Oncorhynchus mykiss caught by sport anglers in the Deschutes River, Oregon. Our objective was to evaluate if steelhead of wild or hatchery origin were equally or disproportionately captured by sport anglers relative to the overall run composition.MethodsWe conducted access‐based angler creel surveys of the Deschutes River steelhead fishery during 2000–2019 and 2021 to observe reported catch of wild and hatchery steelhead. We collated fishery‐independent hatchery‐wild composition data from three locations (two dams and one fish trap) bounding the fishery area we creel sampled. We then used a series of mixed‐effect logistic regression models fit to compare angler catch of wild‐ and hatchery‐origin steelhead relative to their composition at the fishery‐independent sampling locations.ResultThe best‐fit model suggests that anglers were more than twice as likely to observe a wild steelhead in their catch as compared with the chance of the fishery‐dependent sampling sites to observe a wild steelhead. Across all years, wild steelhead were 27–31% of the stock composition at the fishery‐independent sampling sites yet averaged 65% of angler catch.ConclusionDisproportionately high encounter rates of wild‐origin summer steelhead suggest that any adverse impacts associated with catch‐and‐release fishing may be magnified by this effect. We explore some potential mechanisms that could account for this difference and hypothesize that a difference in catchability between wild and hatchery steelhead is the most likely mechanism driving the observed patterns. Regardless of the mechanism, annual catch of wild steelhead is proportionally greater than expectations, given wild steelhead run size compared with that of hatchery steelhead.

A gamma-ray stacking survey of Fermi-LAT undetected globular clusters

ABSTRACT We present evidence for $\gamma$-ray emission from a stacked population of 39 high-latitude globular clusters (GCs) not detected in the Fermi Point Source Catalogue, likely attributable to populations of millisecond pulsars within them. In this work, we use 13 yr of data collected by the Large Area Telescope aboard the Fermi Gamma-Ray Space Telescope to search for a cumulative signal from undetected GCs and compared them to control fields (CFs), selected to match the celestial distribution of the target clusters so as to distinguish the $\gamma$-ray signal from background emission. The joint likelihood distribution of the GCs has a significant separation ($\sim 4\sigma$) from that of the CFs. We also investigate correlations between detected cluster luminosities and other cluster properties such as distance, the number of millisecond pulsars associated with each cluster, and stellar encounter rate but find no significant relationships.

Habitat Utilization of Endemic Green Pit Viper (<i>Peltopelor trigonocephalus</i>) in the Wet Zone, Sri Lanka

The endemic arboreal pit viper Peltopelor trigonocephalus is restricted to three climatic zones of Sri Lanka. In this study, the habitat utilization of P. trigonocephalus was investigated by active search and the quadrate method between April 2021 and March 2022. Data on 49 individuals of P. trigonocephalus were collected from riparian, forest, and open habitats. A high encounter rate was recorded in riparian habitats which included areas with thick vegetation. Based on Principal Component Analysis, some habitat variables were key determining factors of microhabitat preference of this species. Ambient temperature, distance to stream, canopy cover and light intensity were significantly affecting the occupied microhabitat structure. Ambushing behavior was more prominent and time-consuming than other behaviors, with 42.59% of recorded sit-and-wait hunting activity. The results of this research indicate that P. trigonocephalus actively selects and utilizes the most suitable macro and microhabitats in wet zones, providing crucial insights for the conservation and management of the species as well as its natural habitat.

Predator-prey space use and landscape features influence movement behaviors in a large-mammal community.

Predator hunting strategies, such as stalking versus coursing behaviors, are hypothesized to influence antipredator behaviors of prey and can describe the movement behaviors of predators themselves. Predators and prey may alter their movement in relation to predator hunting modes, yet few studies have evaluated how these strategies influence movement behaviors of free-ranging animals in a multiple-predator, multiple-prey system. We fit hidden Markov models (HMM) with movement data derived from >400 GPS-collared ungulates and large predators in eastern Washington, USA. We used these models to test our hypotheses that stalking (cougars [Puma concolor]) and coursing (gray wolves [Canis lupus]) predators would exhibit different broad-scale movement behaviors consistent with their respective hunting strategies in areas that increased the likelihood of encountering or capturing ungulate prey (e.g., habitats selected by deer [Odocoileus spp.]). Similarly, we expected that broadscale movement behaviors of prey would change in response to background levels of predation risk associated with each predator's hunting strategy. We found that predators and ungulate prey adjusted their broadscale movements in response to one another's long-term patterns of habitat selection but not based on differences in predator-hunting strategies. Predators changed their movement behaviors based on the type of prey, whereas ungulates generally reduced movement in areas associated with large predators, regardless of the predator's hunting strategy. Both predator and prey movements varied in response to landscape features but not necessarily based on habitat that would facilitate specific hunting behaviors. Our results suggest that predators and prey adjust their movements at broad temporal scales in relation to long-term patterns of risk and resource distributions, potentially influencing their encounter rates with one another at finer spatiotemporal scales. Habitat features further influenced changes in movement, resulting in a complex combination of movement behaviors in multiple-predator, multiple-prey systems.

Encounter based energy sharing in wildlife communication systems

In this work, the concept of peer-to-peer energy sharing in wildlife communication systems is explored. In this context, wild animals can share energy wirelessly besides their data communications as they opportunistically come into range of each other. Our goal is to find a way to balance the energy among the nodes and minimize this energy loss. We propose a novel encounter-based energy-sharing scheme, called EBES, that utilizes single and multi-hop transmission to achieve energy balance, minimize energy losses, and maximize the lifetime of the wildlife communication system. EBES is based on a variety of parameters, including the amount of energy left in the system and the nodes’ encounter rate, and buffer sizes. In the simulation studies, we considered a wildlife communication network that is involved in data communication and applied EBES over the opportunistic routing protocols such as EBR, Spray&Wait, and Epidemic resulting in a network lifetime increase of 35% and improving the routing protocols performance. Additionally, we compared EBES with the other well-known energy balancing techniques that also contribute to data communication such as EA-Epidemic, EERPFAnt, and OE-OLSR and the results show the remaining energy was improved by 31%, 26%, and 15%, respectively.

Real-world evidence study on the impact of SPECT MPI, PET MPI, cCTA and stress echocardiography on downstream healthcare utilisation in patients with coronary artery disease in the US.

Coronary artery disease (CAD) is associated with a large clinical and economic burden. However, consensus on the optimal approach to CAD diagnosis is lacking. This study sought to compare downstream healthcare resource utilisation following different cardiac imaging modalities, to inform test selection for CAD diagnosis. Claims and electronic health records data from the Decision Resources Group Real-World Evidence US Data Repository were analysed for 2.5 million US patients who underwent single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI), positron emission tomography myocardial perfusion imaging (PET MPI), coronary computed tomography angiography (cCTA), or stress echocardiography between January 2016 and March 2018. Patients were stratified into nine cohorts based on suspected or existing CAD diagnosis, pre-test risk, and prior events or interventions. Downstream healthcare utilisation, including additional diagnostic imaging, coronary angiography, and cardiac-related health system encounters, was compared by cohort and index imaging modality. Among patients with suspected CAD diagnosed within 3 months of the index test, PET MPI was associated with lower downstream utilisation; 25-37% of patients who underwent PET MPI required additional downstream healthcare resources compared with 40-49% of patients who received SPECT MPI, 35-41% of patients who underwent cCTA, and 44-47% of patients who received stress echocardiography. Patients who underwent PET MPI experienced fewer acute cardiac events (5.3-9.4%) and generally had lower rates of healthcare encounters (0.8-4.1%) and invasive coronary angiography (ICA, 15.4-24.2%) than those who underwent other modalities. SPECT MPI was associated with more downstream ICA (31.3-38.2%) and a higher rate of cardiac events (9.5-13.2%) compared with PET MPI (5.3-9.4%) and cCTA (6.9-9.9%). Across all cohorts, additional diagnostic imaging was 1.6 to 4.7 times more frequent with cCTA compared with PET MPI. Choice of imaging modality for CAD diagnosis impacts downstream healthcare utilisation. PET MPI was associated with lower utilisation across multiple metrics compared with other imaging modalities studied.

Droughts reshape apex predator space use and intraguild overlap.

Droughts are increasing in frequency and severity globally due to climate change, leading to changes in resource availability that may have cascading effects on animal ecology. Resource availability is a key driver of animal space use, which in turn influences interspecific interactions like intraguild competition. Understanding how climate-induced changes in resource availability influence animal space use, and how species-specific responses scale up to affect intraguild dynamics, is necessary for predicting broader community-level responses to climatic changes. Although several studies have demonstrated the ecological impacts of drought, the behavioural responses of individuals that scale up to these broader-scale effects are not well known, particularly among animals in top trophic levels like large carnivores. Furthermore, we currently lack understanding of how the impacts of climate variability on individual carnivore behaviour are linked to intraguild dynamics, in part because multi-species datasets collected at timescales relevant to climatic changes are rare. Using 11 years of GPS data from four sympatric large carnivore species in southern Africa-lions (Panthera leo), leopards (Panthera pardus), African wild dogs (Lycaon pictus) and cheetahs (Acinonyx jubatus)-spanning 4 severe drought events, we test whether drought conditions impact (1) large carnivore space use, (2) broad-scale intraguild spatial overlap and (3) fine-scale intraguild interactions. Drought conditions expanded space use across species, with carnivores increasing their monthly home range sizes by 35% (wild dogs) to 66% (leopards). Drought conditions increased the amount of spatial overlap between lions and subordinate felids (cheetahs and leopards) by up to 119%, but only lion-cheetah encounter rates were affected by these changes, declining in response to drought. Our findings reveal that drought has a clear signature on the space use of multiple sympatric large carnivore species, which can alter spatiotemporal partitioning between competing species. Our study thereby illuminates the links between environmental change, animal behaviour and intraguild dynamics. While fine-scale avoidance strategies may facilitate intraguild coexistence during periodic droughts, large carnivore conservation may require considerable expansion of protected areas or revised human-carnivore coexistence strategies to accommodate the likely long-term increased space demands of large carnivores under projected increases in drought intensity.

LMC-driven Anisotropic Boosts in Stream–Subhalo Interactions

Dark matter subhalos are predicted to perturb stellar streams; stream morphologies and dynamics can, therefore, constrain the mass distribution of subhalos. Using FIRE-2 simulations of Milky Way–mass galaxies, we demonstrate that the presence of an LMC analog significantly changes stream–subhalo encounter rates. The LMC analog brings in many subhalos, increasing encounter rates for streams near the massive satellite by 10%–40%. Additionally, the LMC analog displaces the host from its center of mass (inducing reflex motion), which causes a north–south asymmetry in the density and radial velocity distributions of subhalos. This asymmetry, combined with the presence of LMC-analog subhalos, causes encounter rates at the same distance to vary by 50%–70% across the sky, particularly in regions opposite the LMC analog. Furthermore, the LMC analog induces a density wake in the host's dark matter halo, further boosting the encounter rates near the LMC analog. We also explore how stream orbital properties affect encounter rates, finding up to a 50% increase for streams moving retrograde to the LMC analog’s orbit in the opposite quadrant. Finally, we report the encounter rates for Milky Way streams within the context of our simulations, both with and without the presence of an LMC analog. The dependence of encounter rates on stream location, orbit, and their position relative to the LMC has important implications for where to search for streams with spurs and gaps in the Milky Way.

Outpatient Rehabilitation Utilization After Major Limb Loss in Adults Receiving Care in the Military Health System From 2001 to 2017

ObjectiveTo investigate exposures associated with outpatient rehabilitation encounters among Military Health System (MHS) beneficiaries with major limb loss. DesignRetrospective, cohort study. SettingAmerican military treatment facilities and civilian health care facilities that accept TRICARE benefits. ParticipantsAdult MHS beneficiaries with major limb amputation(s) acquired between January 2001 and September 2017 (N=5161). InterventionsNot applicable. Main Outcome MeasuresThis exploratory analysis investigated associations between outpatient rehabilitation care and demographic and amputation characteristics in MHS beneficiaries with major limb loss. ResultsMost beneficiaries were aged 55-64 (36%), male (73%) and retirees/dependents (60%) with enlisted sponsor rank (88%) and single limb loss (89%). The active/reserve beneficiaries were younger, majority male, and more likely to be diagnosed with incident behavioral health conditions. Unadjusted negative binomial regression models revealed increased rates of outpatient rehabilitation encounters in active-duty service members (ADSMs) than in retirees/dependents (rate ratio, 10.02; 95% confidence interval, 9.30-10.80). The rate ratios for sex, sponsor rank, limb(s) lost, incident behavioral health condition, incident traumatic brain injury, incident posttraumatic stress disorder, and outpatient care setting were attenuated after stratification by beneficiary category. Enlisted ADSMs had increased rates of outpatient rehabilitation encounter days compared with officers, whereas retirees/dependents with enlisted sponsors had decreased than those with officer sponsors. ADSMs who accessed outpatient care in direct and private care settings demonstrated high rates of outpatient rehabilitation encounters compared with those who only sought care from private care settings (rate ratio, 4.60; 95% confidence interval, 2.95-6.81). ConclusionsThis study suggests that MHS beneficiaries with major limb loss use outpatient rehabilitation services differently, based on active/reserve duty or retiree/dependent status. This study is the first of its kind to quantify outpatient rehabilitation utilization for military beneficiaries with all-cause major limb loss and may inform MHS policymakers on the rehabilitation needs for combat- and noncombat-related amputee populations.

Thirty-day healthcare encounters after elective uterine artery embolization for fibroids with and without superior hypogastric nerve block

To evaluate how the implementation of superior hypogastric nerve block (SHNB) during uterine artery embolization (UAE) for uterine fibroids impacts same-day discharge and healthcare encounters (HE) within 30 days. 240 patients who underwent successful UAE for fibroids between January 2018 and December 2022 were retrospectively reviewed. HE within 30 days, including emergency department (ED) and urgent care visits, admissions, and readmissions, were categorized as early (0-7 days of discharge) and late (8-30 days of discharge), and related or unrelated to interventional radiology (IR) care. Factors associated with same-day discharge and HE were identified with univariate analyses. Rates of HE based on SHNB status were compared using chi-square tests. Mean age was 46 ± 5 years; 125 patients received UAE with SHNB. Patients who underwent SHNB were significantly more likely to undergo same-day discharge (113/125, 90%) compared to those without SHNB (55/115, 48%) (p<0.001). There were no factors associated with rates of all-cause 30-day HE, including SHNB status (SHNB 17% (21/125) vs no SHNB 10% (12/115), p=0.20). A majority of HE were due to an IR-related cause (26/33, 79%), including abdominal or pelvic pain (22/33, 67%), nausea, vomiting, or poor oral intake (18/33, 55%), and vaginal bleeding (4/33, 12%). Comparing SHNB to no SHNB patients, there was no difference in the proportion of IR-related HE (17/21 (81%) vs 9/12 (75%), p=0.69). UAE with SHNB is associated with significantly higher rates of same-day discharge but similar rates of 30-day healthcare encounters, compared to UAE alone.

Long-term opioid prescribing and the incidence of opioid-related hospitalizations or emergency department visits among patients with metastatic cancer.

200 Background: Many patients with metastatic cancer experience cancer-related pain which is commonly managed using opioids. Although opioids are an effective tool for cancer pain management, their use can result in adverse effects which may be related to long-term use and are understudied in this population. Therefore, we aimed to describe long-term opioid prescribing (LTOP) practices among patients with metastatic cancer and investigate the incidence of opioid-related hospitalizations and emergency department (ED) visits among recipients of long-term prescribing. Methods: This retrospective cohort study used population-based data from Alberta, Canada to identify patients diagnosed with stage IV cancers between 2004-2017 who had at least 1-year of follow-up and were opioid naïve at diagnosis. LTOP was defined as receipt of a ≥90-day supply of opioids with less than a 30-day gap in supply within a 180-day period. Prescribing practices were characterized according to timing (early vs. end-of-life [EoL] onset), morphine equivalent dose, duration, and concurrent medication use. The EoL phase of disease was defined as the year preceding death. The incidence rate of opioid-related encounters was compared between different characteristics of LTOP. Results: The study included a total of 10927 patients, 2521 (23%) of whom received long-term opioid prescribing after diagnosis. LTOP became more common as patients approached EoL, with most patients (53%) having LTOP initiated only within their last year of life. 85 patients (3.4%) experienced an opioid-related hospitalization or ED visit after initiation of LTOP, with an incidence rate of 2.36 (95% CI 1.92, 2.86) encounters per 100 person-years. Higher opioid dosage and concurrent prescribing of anxiolytics, benzodiazepines, antidepressants, and neuroleptic medications were significantly associated with a higher incidence of opioid-related encounters. Conclusions: Long-term opioid prescribing is commonly experienced by patients living with metastatic cancer as a chronic disease. The concurrent use of psychoactive drugs during LTOP was associated with experiencing opioid-related hospitalizations/ED visits.

High hospitalization rates and risk factors among frail patients with cirrhosis: A 10-year population-based cohort study

Cirrhosis-related inpatient hospitalizations have increased dramatically over the past decade. We used a longitudinal dataset capturing a large metropolitan area in the US from 2011-2021 to evaluate contemporary hospitalization rates and risk factors among frail patients with cirrhosis. We conducted a retrospective, longitudinal cohort study using the Chicago Area Patient-Centered Outcomes Research Network (CAPriCORN) database, an electronic health record (EHR) repository that aggregates de-duplicated data across seven healthcare systems in the Chicago metropolitan area, from 2011-2021. The primary outcome of our study was the rate of hospitalization encounters. Frailty was defined by the Hospital Frailty Risk Score. Hospitalization rates were reported per 100 patients per year and a multivariable logistic regression analysis identified predictors of annual hospitalization probability. During the study period, of 36,971 patients, 16,265 patients (44%) were hospitalized (compensated: 18.4%, decompensated: 81.6%). Hospitalization rates were highest in patients with decompensated cirrhosis, reaching nearly 77.3 hospitalizations/100 patients per year. Hospitalization rates among patients with compensated cirrhosis were also high (14.2 vs. 77.3 hospitalization/100 patients per year), with odds of annual hospitalization three times (OR 3.1; 95%CI 2.9-3.4) as high among compensated patients with intermediate frailty and five times (OR 5.2; 95%CI 4.5-6.0) as high among those with severe frailty (compared to compensated patients with low frailty). Compensated and decompensated cirrhosis patients with intermediate to severe frailty face a substantially increased odds of annual hospitalizations compared to those with low frailty. Future work should focus on targeted interventions to incorporate routine frailty screenings into cirrhosis care and to ultimately minimize high hospitalization rates.

Seasonal changes in the abundance and distribution of large terrestrial mammals in old Oyo National Park, Nigeria

Seasonal distribution of large terrestrial mammals in African protected areas is shaped by factors such as food and water availability, breeding cycles, and predation risks. This study utilised encounter rates derived from diurnal distance sampling to examine seasonal variations in the abundance and distribution of these mammals within Old Oyo National Park, Nigeria. Notably, the abundance and distribution in the Marguba range, characterised by mixed open savanna woodland, differed significantly between the dry and wet seasons, as well as among various sub-habitats and ranges during the dry season. The impact of key factors—(1) resource availability (food and water) and/or (2) poaching threat—remains critical and potentially influential in driving these seasonal differences. Further investigation to ascertain the effect of poaching and determine the impact of other controlling factors is crucial. Understanding the effects of these factors is essential for the effective and sustainable management and conservation of large terrestrial mammals in the study area.

Discovery of a Millisecond Pulsar Associated with Terzan 6

Observations show that globular clusters (GCs) might be among the best places to find millisecond pulsars (MSPs). However, the GC Terzan 6 seems to be an exception without any pulsar discovered, although its high stellar encounter rate suggests that it harbors dozens of them. We report the discovery of the first radio pulsar, PSR J1750–3116A, likely associated with Terzan 6 in a search of C-band (4–8 GHz) data from the Robert C. Byrd Green Bank Telescope with a spin period of 5.33 ms and dispersion measure (DM) ≃ 383 pc cm−3. The mean flux density of this pulsar is approximately 3 μJy. The DM agrees well with predictions from the Galactic free electron density model, assuming a distance of 6.7 kpc for Terzan 6. PSR J1750–3116A is likely an isolated MSP, potentially formed through dynamical interactions, considering the core-collapsed classification and the exceptionally high stellar encounter rate of Terzan 6. This is the highest radio frequency observation that has led to the discovery of a pulsar in a GC to date. While L-band (1–2 GHz) observations of this cluster are unlikely to yield significant returns due to propagation effects, we predict that further pulsar discoveries in Terzan 6 will be made by existing radio telescopes at higher frequencies.

Floating active carpets drive transport and aggregation in aquatic ecosystems

Communities of swimming microorganisms often thrive near liquid–air interfaces. We study how such ‘active carpets’ shape their aquatic environment by driving biogenic transport in the water column beneath them. The hydrodynamic stirring that active carpets generate leads to diffusive upward fluxes of nutrients from deeper water layers, and downward fluxes of oxygen and carbon. Combining analytical theory and simulations, we examine the biogenic transport by studying fundamental metrics, including the single and pair diffusivity, the first passage time for particle pair encounters and the rate of particle aggregation. Our findings reveal that the hydrodynamic fluctuations driven by active carpets have a region of influence that reaches orders of magnitude further in distance than the size of the organisms. These non-equilibrium fluctuations lead to a strongly enhanced diffusion of particles, which is anisotropic and space dependent. Fluctuations also facilitate encounters of particle pairs, which we quantify by analysing their velocity pair correlation functions as a function of distance between the particles. We found that the size of the particles plays a crucial role in their encounter rates, with larger particles situated near the active carpet being more favourable for aggregation. Overall, this research broadens our comprehension of aquatic systems out of equilibrium and how biologically driven fluctuations contribute to the transport of fundamental elements in biogeochemical cycles.

Abstract B067: A mixed-methods health services analysis of disparities and social vulnerabilities in childhood cancer survivors’ long-term follow-up care

Abstract Pediatric cancer affects &amp;gt;15,000 US children annually. Treatment advances have led to an increase in those surviving the disease, and these patients must be managed to control their long-term comorbidities. Unfortunately, a majority are nonadherent to post-treatment care guidelines and become lost to follow-up. This is especially true for those from underserved backgrounds, including survivors who are Black and Latine. To help understand this disparity, we studied the organization and delivery of pediatric cancer survivorship care at an urban comprehensive cancer center. Research included: 1) a qualitative study exploring healthcare barriers and facilitators of survivors’ adherence to long-term follow-up care, as determined by N=31 key informants (pediatric oncology care providers, administrators), and; 2) a retrospective cohort study (2007- 2020) among N&amp;gt;350 survivors (10% Black, 28% Latine, 12% Asian; 47% from vulnerable neighborhoods) assessing social determinants of health (SDoH) and its cofactors, adjusted for vital status. Interviews were recorded, transcribed, and thematically analyzed using software (K&amp;gt;.70). Three major themes emerged in survivors’ adherence: 1) healthcare system-level influences (69%), SDoH (25%), and intra/interpersonal factors (16%). At the system-level, informants noted opportunities to strengthen adherence, especially for survivors from underserved backgrounds, including the provision of greater social support (14%), easing appointment scheduling (11%), offering high-quality ambulatory and specialty care within the system upon entering young adulthood (12%), and cultural competency training for staff (6%). Among SDoH, informants noted transportation and geographic challenges in accessing the healthcare system (25%), insurance coverage for follow-up care (17%), and strengthening trust with marginalized communities (17%). For intra/interpersonal factors, time- and age-related changes in survivors’ medical needs were acknowledged as barriers to be overcome (28%), along with providing greater patient education (11%) and heightened salience of follow-up care (17%). Conversely, the provider-patient relationship was noted as a strength in promoting adherence (23%). Retrospective cohort results revealed that survivors’ attendance at dedicated clinics was suboptimal (52% &amp;gt;= 2 years off-therapy), as were rates of system-wide ambulatory care encounters 3+ and 5+ years post-therapy. At the bivariate level, non-Hispanic Black survivors (68%), adolescents (58%), and those with CNS tumors (81%) had the lowest likelihood of survivorship clinic attendance (p&amp;lt;.05)–underscoring qualitative findings on SDoH. Area-level SDoH indices were unrelated to the cohort’s adherence, highlighting qualitative findings on intra/interpersonal barriers and facilitators. These data lend insights into transformations possible within the organization and delivery of healthcare to young survivors, especially those from underrepresented backgrounds, including greater attention to SDoH and strengthening cultural competence among health system employees. Citation Format: Marcelo Sleiman Jr, Tara Suntum, Nina Kadan-Lottick, Brianna Miller, Mary R Yockel, Arnold Potosky, Chiranjeev Dash, Adil Alaoui, Burton Appel, Ken Tercyak. A mixed-methods health services analysis of disparities and social vulnerabilities in childhood cancer survivors’ long-term follow-up care [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B067.