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Risso’s dolphin (Grampus griseus) is a widely distributed oceanic species; its global and regional population structure remains poorly understood. To assess their genetic diversity and connectivity in British waters, we analysed tissue samples from stranded individuals collected between 1992 and 2016 using 16 nuclear microsatellite loci and a 433-bp mitochondrial DNA (mtDNA) sequence. Microsatellite analyses (STRUCTURE, AMOVA, and PCA) consistently indicated a single genetic cluster with no significant geographic differentiation among sampling sites, suggesting a panmictic population. BayesAss results further supported high gene flow and limited isolation among regions. The mtDNA dataset identified six haplotypes with low haplotype and nucleotide diversity, showing no spatial structuring within the British Isles. Phylogenetic reconstruction revealed that all British haplotypes were endemic and formed a monophyletic clade closely related to haplotypes from the Azores in the North Atlantic. Together, the nuclear and mtDNA data indicate low genetic diversity and a lack of population subdivision among British Risso’s dolphins. These findings imply recent colonisation and high dispersal capability, consistent with patterns observed in other wide-ranging marine mammals. Continued monitoring, broader geographic sampling, and large-scale photo-identification are needed to refine understanding of Risso’s dolphin population dynamics and to inform conservation management.
The Deep South has the highest prevalence of obesity, diabetes, and hypertension in the United States, with marked disparities by race, socioeconomic status, and rurality. Addressing these disparities requires not only effective interventions, but also a translational science workforce equipped to design, implement, and scale solutions in real-world settings. The Forge AHEAD Center was established to improve cardiometabolic health outcomes across the Deep South by advancing both research and scientific workforce development. As a central component of this mission, the Center has developed the “Pilot Plus” model, an integrated framework that combines pilot funding with structured training in translational science, multidisciplinary team-based mentorship, and embedded community engagement. Early-stage investigators are supported through coordinated access to methodological expertise, including dissemination and implantation science and assessment of social determinants of health, while community stakeholders are incorporated into the research process. By aligning funding, training, and infrastructure within a single program, the Pilot Plus model addresses fragmentation in traditional research development approaches and expands access to critical resources across institutions. This model provides an adaptable framework for strengthening translational research capacity and developing a cadre of demographically varied investigators prepared to advance health outcomes in regions with a high burden of chronic disease
Recruitment for rare disease studies is challenging due to small eligible populations. Traditional clinical research management systems often lack tools to track recruitment contacts prior to enrollment. The NET-PRO study, focused on neuroendocrine tumors (NETs), implemented a participation monitoring system to enhance recruitment efficiency and representativeness.
Methods:
NET-PRO is a multicenter cohort study of 2538 adults diagnosed with gastroenteropancreatic (GEP) or lung NETs between January 2018 and September 2024. Recruitment occurred from January 2022 to February 2025 across 14 U.S. medical centers. Sites used flexible recruitment methods (email, mail, phone, in-clinic) and tracked contacts using REDCap-based tools. Participant characteristics were analyzed by enrollment mode (online or mail) and recruitment difficulty (number of contacts required prior to enrollment) using standardized mean differences, chi-square tests, and ANOVA.
Results:
Of 9279 contacted patients, 2675 consented (28.8%) and 2538 enrolled (27.4%). Most enrolled online (83.2%), while 16.8% enrolled by mail. Mail respondents were older, had lower education and income, and more comorbidities. Among those enrolled, recruitment difficulty was associated with older age, lower education and income, but not comorbidity. Over half of the most difficult-to-recruit participants enrolled online. Contact methods varied by attempt, with email dominating early contacts and phone/mail used more in later attempts.
Conclusions:
A participation monitoring tool supported flexible, multimodal recruitment and improved sample representativeness in a rare cancer study. Tracking recruitment contacts enabled adaptive strategies and may reduce bias in observational research by enabling better outreach to harder-to-reach populations.
Over 15 million children in the United States have been infected with COVID-19; nearly 2,000 have died. Approval of COVID-19 vaccines for children enabled reductions in disease severity and mortality. Disparities in vaccine adoption exist along racial, ethnic, and rural–urban lines, with lower uptake among medically underserved populations (e.g. Black, non-Hispanic White rural populations) compared to urban White populations. This study examined efforts to recruit and engage a diverse cohort as part of a vaccine communication randomized trial conducted across 15 states and compared demographic characteristics of the enrolled cohort to the broader US population. To enhance recruitment of diverse populations, eligible clinics had to serve a significant proportion of medically underserved individuals based on race, ethnicity, or geographic location. Coordinators used both traditional (in-person daily clinic schedule review) and retrospective (EHR and billing data review) recruitment methods adapted to enrich engagement with focus populations. Demographic characteristics were compared to national statistics obtained from the CDC’s Household Pulse Survey. In total, 2999 parents/caregivers were screened; 725 were randomized (24.1%). Comparing enrolled subjects to the demographics of participating states, 17.3% vs 9.8% self-identified as Hispanic, 39.6% vs 13.0% as Black. Additionally, 34.3% self-described as living in a rural area. Of the 725 randomized, 512 (70.6%) completed the baseline survey. Of these 512, 422 (82.4%) also completed the final survey of the 24-week study. This analysis demonstrates the Institutional Development Award States Pediatric Clinical Trials Network can successfully recruit and engage populations from diverse and underrepresented populations in research.
Genetic research on nicotine dependence has utilized multiple assessments that are in weak agreement.
Methods
We conducted a genome-wide association study (GWAS) of nicotine dependence defined using the Diagnostic and Statistical Manual of Mental Disorders (DSM-NicDep) in 61,861 individuals (47,884 of European ancestry [EUR], 10,231 of African ancestry, and 3,746 of East Asian ancestry) and compared the results to other nicotine-related phenotypes.
Results
We replicated the well-known association at the CHRNA5 locus (lead single-nucleotide polymorphism [SNP]: rs147144681, p = 1.27E−11 in EUR; lead SNP = rs2036527, p = 6.49e−13 in cross-ancestry analysis). DSM-NicDep showed strong positive genetic correlations with cannabis use disorder, opioid use disorder, problematic alcohol use, lung cancer, material deprivation, and several psychiatric disorders, and negative correlations with respiratory function and educational attainment. A polygenic score of DSM-NicDep predicted DSM-5 tobacco use disorder criterion count and all 11 individual diagnostic criteria in the independent National Epidemiologic Survey on Alcohol and Related Conditions-III sample. In genomic structural equation models, DSM-NicDep loaded more strongly on a previously identified factor of general addiction liability than a “problematic tobacco use” factor (a combination of cigarettes per day and nicotine dependence defined by the Fagerström Test for Nicotine Dependence). Finally, DSM-NicDep showed a strong genetic correlation with a GWAS of tobacco use disorder as defined in electronic health records (EHRs).
Conclusions
Our results suggest that combining the wide availability of diagnostic EHR data with nuanced criterion-level analyses of DSM tobacco use disorder may produce new insights into the genetics of this disorder.
Recent changes to US research funding are having far-reaching consequences that imperil the integrity of science and the provision of care to vulnerable populations. Resisting these changes, the BJPsych Portfolio reaffirms its commitment to publishing mental science and advancing psychiatric knowledge that improves the mental health of one and all.
Specimens of Tulaneia amabilia Runnegar and Horodyski n. gen n. sp. (previously Ernietta plateauensis Pflug) discovered by RJH in 1991 at a site in the Montgomery Mountains near Johnnie, Nevada, are described for the first time. All of the material from the original locality was from float, but its stratigraphic position within the lowest siliciclastic to dolostone interval of the lower member of the Wood Canyon Formation (LMWCF) was confirmed by subsequent discoveries. Because the upper part of the LMWCF contains Treptichnus pedum (Seilacher), the Ediacaran–Cambrian boundary has long been drawn at its first appearance. However, in the Esmeralda Member of the Deep Spring Formation in the White-Inyo Mountains, California, and at Mount Dunfee, Nevada, another Cambrian ichnofossil, ‘Plagiogmus’, which is now Psammichnites gigas arcuatus (Roedel), is found just beneath the nadir of the basal Cambrian isotope excursion (BACE). Because the nadir of the BACE excursion is older than ca. 539 Ma in Mexico, the oldest occurrences of Treptichnus pedum in the LMWCF are latest—not earliest—Fortunian in age, and there is no need to reduce the age of the eon boundary from ca. 539 to ca. 533 Ma. Tulaneia resembles Ernietta and other erniettomorphs in being composed of tubular modules with planar common surfaces, but its overall shape was tabular and unidirectional rather than sack or frond shaped. We also illustrate and briefly describe other trace and body fossils from the LMWCF and re-illustrate previously published specimens of Psammichnites gigas arcuatus in order to document its earliest occurrence in the Great Basin.
The new software package OpenMx 2.0 for structural equation and other statistical modeling is introduced and its features are described. OpenMx is evolving in a modular direction and now allows a mix-and-match computational approach that separates model expectations from fit functions and optimizers. Major backend architectural improvements include a move to swappable open-source optimizers such as the newly written CSOLNP. Entire new methodologies such as item factor analysis and state space modeling have been implemented. New model expectation functions including support for the expression of models in LISREL syntax and a simplified multigroup expectation function are available. Ease-of-use improvements include helper functions to standardize model parameters and compute their Jacobian-based standard errors, access to model components through standard R $ mechanisms, and improved tab completion from within the R Graphical User Interface.
To describe the effect of a Stenotrophomonas maltophilia (SM) respiratory culture nudge on antibiotic use in colonized patients.
Design:
IRB-approved quasi-experiment.
Setting:
Five acute-care hospitals in Michigan.
Patients:
Adult patients with SM respiratory culture between 01/01/2022 and 01/27/2023 (pre-nudge) and 03/27/2023–12/31/2023 (post-nudge). Patients with active community/hospital/ventilator-acquired pneumonia or who received SM-targeted antibiotics at the time of culture were excluded.
Methods:
A nudge comment was implemented 02/2023 stating: “S. maltophilia is a frequent colonizer of the respiratory tract. Clinical correlation for infection is required. Colonizers do not require antibiotic treatment.” The primary outcome was no treatment with SM-therapy; secondary outcomes were treatment with SM-therapy ≥72 hrs, length of stay, and in-hospital, all-cause mortality. Safety outcomes included antibiotic-associated adverse drug events (ADEs).
Results:
94 patients were included: 53 (56.4%) pre- and 41 (43.6%) post-nudge. Most patients were men (53, 56.4%), had underlying lung disease (61, 64.8%), and required invasive ventilatory support (70, 74.5%). Eleven (11.7%) patients resided in a long-term care facility. No treatment with SM therapy was observed in 13 (23.1%) pre- versus 32 (78.0%) post-nudge patients (P <0.001). There were no differences in secondary outcomes. Antibiotic-associated ADEs were common (33/41, 76%) in patients who received ≥72hrs of SM-therapy: fluid overload (18, 44%), hyponatremia (17, 42%), elevated SCr (12, 29%), hyperkalemia (5, 12%). After adjustment for confounders, post-nudge was associated with 11-fold increased odds of no treatment with SM-therapy (adjOR, 11.72; 95%CI, 4.18–32.83).
Conclusions:
A targeted SM nudge was associated with a significant reduction in treatment of colonization, with similar patient outcomes. SM-treated patients frequently developed antibiotic-associated ADEs.
Society of Thoracic Surgeons Congenital Heart Surgery Database is the largest congenital heart surgery database worldwide but does not provide information beyond primary episode of care. Linkage to hospital electronic health records would capture complications and comorbidities along with long-term outcomes for patients with CHD surgeries. The current study explores linkage success between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health record data in North Carolina and Georgia.
Methods:
The Society of Thoracic Surgeons Congenital Heart Surgery Database was linked to hospital electronic health records from four North Carolina congenital heart surgery using indirect identifiers like date of birth, sex, admission, and discharge dates, from 2008 to 2013. Indirect linkage was performed at the admissions level and compared to two other linkages using a “direct identifier,” medical record number: (1) linkage between Society of Thoracic Surgeons Congenital Heart Surgery Database and electronic health records from a subset of patients from one North Carolina institution and (2) linkage between Society of Thoracic Surgeons data from two Georgia facilities and Georgia’s CHD repository, which also uses direct identifiers for linkage.
Results:
Indirect identifiers successfully linked 79% (3692/4685) of Society of Thoracic Surgeons Congenital Heart Surgery Database admissions across four North Carolina hospitals. Direct linkage techniques successfully matched Society of Thoracic Surgeons Congenital Heart Surgery Database to 90.2% of electronic health records from the North Carolina subsample. Linkage between Society of Thoracic Surgeons and Georgia’s CHD repository was 99.5% (7,544/7,585).
Conclusions:
Linkage methodology was successfully demonstrated between surgical data and hospital-based electronic health records in North Carolina and Georgia, uniting granular procedural details with clinical, developmental, and economic data. Indirect identifiers linked most patients, consistent with similar linkages in adult populations. Future directions include applying these linkage techniques with other data sources and exploring long-term outcomes in linked populations.
With the rise of online references, podcasts, webinars, self-test tools, and social media, it is worthwhile to understand whether textbooks continue to provide value in medical education, and to assess the capacity they serve during fellowship training.
Methods:
A prospective mixed-methods study based on surveys that were disseminated to seven paediatric cardiology fellowship programmes around the world. Participants were asked to read an assigned chapter of Anderson’s Pediatric Cardiology 4th Edition textbook, followed by the completion of the survey. Open-ended questions included theming and grouping responses as appropriate.
Results:
The survey was completed by 36 participants. When asked about the content, organisation, and utility of the chapter, responses were generally positive, at greater than 89%. The chapters, overall, were rated relatively easy to read, scoring at 6.91, with standard deviations plus or minus 1.72, on a scale from 1 to 10, with higher values meaning better results. When asked to rank their preferences in where they obtain educational content, textbooks were ranked the second highest, with in-person teaching ranking first. Several themes were identified including the limitations of the use of textbook use, their value, and ways to enhance learning from their reading. There was also a near-unanimous desire for more time to self-learn and read during fellowship.
Conclusions:
Textbooks are still highly valued by trainees. Many opportunities exist, nonetheless, to improve how they can be organised to deliver information optimally. Future efforts should look towards making them more accessible, and to include more resources for asynchronous learning.
NASA’s all-sky survey mission, the Transiting Exoplanet Survey Satellite (TESS), is specifically engineered to detect exoplanets that transit bright stars. Thus far, TESS has successfully identified approximately 400 transiting exoplanets, in addition to roughly 6 000 candidate exoplanets pending confirmation. In this study, we present the results of our ongoing project, the Validation of Transiting Exoplanets using Statistical Tools (VaTEST). Our dedicated effort is focused on the confirmation and characterisation of new exoplanets through the application of statistical validation tools. Through a combination of ground-based telescope data, high-resolution imaging, and the utilisation of the statistical validation tool known as TRICERATOPS, we have successfully discovered eight potential super-Earths. These planets bear the designations: TOI-238b (1.61$^{+0.09} _{-0.10}$ R$_\oplus$), TOI-771b (1.42$^{+0.11} _{-0.09}$ R$_\oplus$), TOI-871b (1.66$^{+0.11} _{-0.11}$ R$_\oplus$), TOI-1467b (1.83$^{+0.16} _{-0.15}$ R$_\oplus$), TOI-1739b (1.69$^{+0.10} _{-0.08}$ R$_\oplus$), TOI-2068b (1.82$^{+0.16} _{-0.15}$ R$_\oplus$), TOI-4559b (1.42$^{+0.13} _{-0.11}$ R$_\oplus$), and TOI-5799b (1.62$^{+0.19} _{-0.13}$ R$_\oplus$). Among all these planets, six of them fall within the region known as ‘keystone planets’, which makes them particularly interesting for study. Based on the location of TOI-771b and TOI-4559b below the radius valley we characterised them as likely super-Earths, though radial velocity mass measurements for these planets will provide more details about their characterisation. It is noteworthy that planets within the size range investigated herein are absent from our own solar system, making their study crucial for gaining insights into the evolutionary stages between Earth and Neptune.
Globally, human house types are diverse, varying in shape, size, roof type, building materials, arrangement, decoration and many other features. Here we offer the first rigorous, global evaluation of the factors that influence the construction of traditional (vernacular) houses. We apply macroecological approaches to analyse data describing house features from 1900 to 1950 across 1000 societies. Geographic, social and linguistic descriptors for each society were used to test the extent to which key architectural features may be explained by the biophysical environment, social traits, house features of neighbouring societies or cultural history. We find strong evidence that some aspects of the climate shape house architecture, including floor height, wall material and roof shape. Other features, particularly ground plan, appear to also be influenced by social attributes of societies, such as whether a society is nomadic, polygynous or politically complex. Additional variation in all house features was predicted both by the practices of neighouring societies and by a society's language family. Collectively, the findings from our analyses suggest those conditions under which traditional houses offer solutions to architects seeking to reimagine houses in light of warmer, wetter or more variable climates.
Late-life depression (LLD) is common and frequently co-occurs with neurodegenerative diseases of aging. Little is known about how heterogeneity within LLD relates to factors typically associated with neurodegeneration. Varying levels of anxiety are one source of heterogeneity in LLD. We examined associations between anxiety symptom severity and factors associated with neurodegeneration, including regional brain volumes, amyloid beta (Aβ) deposition, white matter disease, cognitive dysfunction, and functional ability in LLD.
Participants and Measurements:
Older adults with major depression (N = 121, Ages 65–91) were evaluated for anxiety severity and the following: brain volume (orbitofrontal cortex [OFC], insula), cortical Aβ standardized uptake value ratio (SUVR), white matter hyperintensity (WMH) volume, global cognition, and functional ability. Separate linear regression analyses adjusting for age, sex, and concurrent depression severity were conducted to examine associations between anxiety and each of these factors. A global regression analysis was then conducted to examine the relative associations of these variables with anxiety severity.
Results:
Greater anxiety severity was associated with lower OFC volume (β = −68.25, t = −2.18, p = .031) and greater cognitive dysfunction (β = 0.23, t = 2.46, p = .016). Anxiety severity was not associated with insula volume, Aβ SUVR, WMH, or functional ability. When examining the relative associations of cognitive functioning and OFC volume with anxiety in a global model, cognitive dysfunction (β = 0.24, t = 2.62, p = .010), but not OFC volume, remained significantly associated with anxiety.
Conclusions:
Among multiple factors typically associated with neurodegeneration, cognitive dysfunction stands out as a key factor associated with anxiety severity in LLD which has implications for cognitive and psychiatric interventions.
Translatability of preclinical results remains a major obstacle in neuropsychiatric research. Even when cognitive tests in preclinical models show translational validity for human testing, with sensitivity to clinical deficits, there remains the issue of heterogeneity among human participants. Norming of performance on cognitive tasks enable corrections for any differences in performance that may arise from the influence of socioeconomic factors, and thus a more direct comparison with preclinical testing results. The 5-choice continuous performance task (5C-CPT) is a test sensitive to changes in sustained attention and cognitive control in rodent manipulations and clinical populations, including schizophrenia and bipolar disorder. Herein, we present normed results of 5C-CPT data from a cohort of human participants, enabling greater comparison to future clinical and rodent testing.
Participants and Methods:
5C-CPT data were generated from a range of participants from the Translational Methamphetamine AIDS Research Center (n=82) and a study of bipolar disorder (n=45). Participant demographics were as follows: Age M=38.5, SD=16.7, Education: M=14.5, SD=1.9, 45% female, 10% Asian, 17% African American, 27% Hispanic, and 46% non-Hispanic White. We used the test2norm R-package to create norms for each of the major outcomes from the 5C-CPT. Non-normally distributed raw scores were transformed to generate more normally distributed data needed for the norming process. Raw scores were first converted into uniform scaled scores that range from 0-20 where a higher score indicated better performance. We then generated T-score formulas, which are standardized residuals and scaled to have a mean of 50 and standard deviation of 10. The residuals are obtained from regressions, modeled using multiple fractional polynomial method (MFP), which regresses scaled scores on demographic variables, which a user wishes to control for (gender, age, education, ethnicity, etc.). MFP models allow to fit non-linear effects for numeric demographic factors (e.g., age), if such effects exist.
Results:
New, demographically corrected T-score formulas were calculated for each major outcome of the 5C-CPT: reaction time (MCL), reaction time variability (VarRT), dprime, hit rate (HR) and false-alarm rate (FAR). MFP models showed that age had a significant effect on MCL, VarRT, dprime, and HR (all p<0.01), while gender only showed a significant effect for MCL and VarRT (all p<0.05). Interestingly, education and ethnicity did not show a significant effect for any MFP model and none of the demographic factors (age, education, gender, ethnicity) were significant in the model for FAR. As defined in the test2norm package, all scaled scores had a mean of 10 and SD of 3 and all T-scores had a mean of 50 and SD of 10.
Conclusions:
The 5C-CPT is a test of attention and cognitive control available for human testing, reverse-translated from rodent studies. The normative data generated here will enable future comparisons of data without the need for additional control studies. Furthermore, comparing these normative data to manipulations will enable further comparisons to rodent testing, with manipulations relative to baseline becoming more meaningful. Thus, the 5C-CPT is a viable tool for conducting cross-species translational research toward developing novel therapeutics that treat dysfunctional attentional and cognitive control.
Blood-based biomarkers offer a more feasible alternative to Alzheimer’s disease (AD) detection, management, and study of disease mechanisms than current in vivo measures. Given their novelty, these plasma biomarkers must be assessed against postmortem neuropathological outcomes for validation. Research has shown utility in plasma markers of the proposed AT(N) framework, however recent studies have stressed the importance of expanding this framework to include other pathways. There is promising data supporting the usefulness of plasma glial fibrillary acidic protein (GFAP) in AD, but GFAP-to-autopsy studies are limited. Here, we tested the association between plasma GFAP and AD-related neuropathological outcomes in participants from the Boston University (BU) Alzheimer’s Disease Research Center (ADRC).
Participants and Methods:
This sample included 45 participants from the BU ADRC who had a plasma sample within 5 years of death and donated their brain for neuropathological examination. Most recent plasma samples were analyzed using the Simoa platform. Neuropathological examinations followed the National Alzheimer’s Coordinating Center procedures and diagnostic criteria. The NIA-Reagan Institute criteria were used for the neuropathological diagnosis of AD. Measures of GFAP were log-transformed. Binary logistic regression analyses tested the association between GFAP and autopsy-confirmed AD status, as well as with semi-quantitative ratings of regional atrophy (none/mild versus moderate/severe) using binary logistic regression. Ordinal logistic regression analyses tested the association between plasma GFAP and Braak stage and CERAD neuritic plaque score. Area under the curve (AUC) statistics from receiver operating characteristics (ROC) using predicted probabilities from binary logistic regression examined the ability of plasma GFAP to discriminate autopsy-confirmed AD status. All analyses controlled for sex, age at death, years between last blood draw and death, and APOE e4 status.
Results:
Of the 45 brain donors, 29 (64.4%) had autopsy-confirmed AD. The mean (SD) age of the sample at the time of blood draw was 80.76 (8.58) and there were 2.80 (1.16) years between the last blood draw and death. The sample included 20 (44.4%) females, 41 (91.1%) were White, and 20 (44.4%) were APOE e4 carriers. Higher GFAP concentrations were associated with increased odds for having autopsy-confirmed AD (OR=14.12, 95% CI [2.00, 99.88], p=0.008). ROC analysis showed plasma GFAP accurately discriminated those with and without autopsy-confirmed AD on its own (AUC=0.75) and strengthened as the above covariates were added to the model (AUC=0.81). Increases in GFAP levels corresponded to increases in Braak stage (OR=2.39, 95% CI [0.71-4.07], p=0.005), but not CERAD ratings (OR=1.24, 95% CI [0.004, 2.49], p=0.051). Higher GFAP levels were associated with greater temporal lobe atrophy (OR=10.27, 95% CI [1.53,69.15], p=0.017), but this was not observed with any other regions.
Conclusions:
The current results show that antemortem plasma GFAP is associated with non-specific AD neuropathological changes at autopsy. Plasma GFAP could be a useful and practical biomarker for assisting in the detection of AD-related changes, as well as for study of disease mechanisms.
We recently reported on the radio-frequency attenuation length of cold polar ice at Summit Station, Greenland, based on bi-static radar measurements of radio-frequency bedrock echo strengths taken during the summer of 2021. Those data also allow studies of (a) the relative contributions of coherent (such as discrete internal conducting layers with sub-centimeter transverse scale) vs incoherent (e.g. bulk volumetric) scattering, (b) the magnitude of internal layer reflection coefficients, (c) limits on signal propagation velocity asymmetries (‘birefringence’) and (d) limits on signal dispersion in-ice over a bandwidth of ~100 MHz. We find that (1) attenuation lengths approach 1 km in our band, (2) after averaging 10 000 echo triggers, reflected signals observable over the thermal floor (to depths of ~1500 m) are consistent with being entirely coherent, (3) internal layer reflectivities are ≈–60$\to$–70 dB, (4) birefringent effects for vertically propagating signals are smaller by an order of magnitude relative to South Pole and (5) within our experimental limits, glacial ice is non-dispersive over the frequency band relevant for neutrino detection experiments.
We assessed factors associated with increased risk to loss of follow-up with infectious diseases staff in OPAT patients. Discharge to subacute healthcare facilities is strongly associated with loss to follow-up. We did not identify sociodemographic disparities. Poor communication between OPAT providers and subacute healthcare facilities remains a serious issue.