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Abstract The development of machine learning models has led to an abundance of datasets containing quantum mechanical (QM) calculations for molecular and material systems. However, traditional training methods for machine learning models are unable to leverage the plethora of data available as they require that each dataset be generated using the same QM method. Taking machine learning interatomic potentials (MLIPs) as an example, we show that meta-learning techniques, a recent advancement from the machine learning community, can be used to fit multiple levels of QM theory in the same training process. Meta-learning changes the training procedure to learn a representation that can be easily re-trained to new tasks with small amounts of data. We then demonstrate that meta-learning enables simultaneously training to multiple large organic molecule datasets. As a proof of concept, we examine the performance of a MLIP refit to a small drug-like molecule and show that pre-training potentials to multiple levels of theory with meta-learning improves performance. This difference in performance can be seen both in the reduced error and in the improved smoothness of the potential energy surface produced. We therefore show that meta-learning can utilize existing datasets with inconsistent QM levels of theory to produce models that are better at specializing to new datasets. This opens new routes for creating pre-trained, foundation models for interatomic potentials.

Aim: To quantify financial toxicity and out-of-pocket costs for patients with HNC in Australia and explore their relationship with health-related quality of life (HRQoL). Methods: A cross-sectional survey was administered to patients with HNC 1–3 years after radiotherapy at a regional hospital in Australia. The survey included questions on sociodemographics, out-of-pocket expenses, HRQoL, and the Financial Index of Toxicity (FIT) tool. The relationship between high financial toxicity scores (top quartile) and HRQoL was explored. Results: Of the 57 participants included in the study, 41 (72%) reported out-of-pocket expenses at a median of AUD 1796 (IQR AUD 2700) and a maximum of AUD 25,050. The median FIT score was 13.9 (IQR 19.5) and patients with high financial toxicity (n = 14) reported poorer HRQoL (76.5 vs. 114.5, p < 0.001). Patients who were not married had higher FIT scores (23.1 vs. 11.1, p = 0.01), as did those with lower education (19.3 vs. 11.1, p = 0.06). Participants with private health insurance had lower financial toxicity scores (8.3 vs. 17.6, p = 0.01). Medications (41%, median AUD 400), dietary supplements (41%, median AUD 600), travel (36%, median AUD 525), and dental (29%, AUD 388) were the most common out-of-pocket expenses. Participants living in rural locations (≥100 km from the hospital) had higher out-of-pocket expenses (AUD 2655 vs. AUD 730, p = 0.01). Conclusion: Financial toxicity is associated with poorer HRQoL for many patients with HNC following treatment. Further research is needed to investigate interventions aimed at reducing financial toxicity and how these can best be incorporated into routine clinical care.

The purpose of this study is to test, for the first time, the association between spatial social polarization and incarceration among people who inject drugs (PWID) in 19 large U.S. metropolitan statistical areas (MSAs) in 2015. PWID were recruited from MSAs for the Centers for Disease Control and Prevention's 2015 National HIV Behavioral Surveillance. Administrative data were used to describe the ZIP-code areas, counties, and MSAs where PWID lived. We operationalized spatial polarization using the Index of Concentration at the Extremes (ICE), a measure that reflects polarization in race and household income at the ZIP-code level. We tested the association between spatial polarization and odds of past-year arrest and detainment using multilevel multivariable models. We found 37% of the sample reported being incarcerated in the past year. Report of past-year incarceration varied by race/ethnicity: 45% of non-Hispanic white PWID reported past-year incarceration, as did 25% of non-Hispanic Black PWID, and 43% of Hispanic/Latino PWID (N = 9047). Adjusted odds ratios suggest that Black PWID living in ZIP-code areas with a higher ICE score, meaning more white and affluent, had higher odds of past-year incarceration, compared to white PWID. In previous research, incarceration has been found to be associated with HIV acquisition and can deter PWID from engaging in harm reduction activities.

BackgroundEfforts to mitigate HIV transmission among gay and bisexual men have not been sufficient to level persistent racial inequities which now extend to the use of daily oral pre-exposure prophylaxis (PrEP) for HIV prevention. Community-involved ethnographic research is crucial to galvanizing collaboration between patients, researchers, and policymakers to identify the social determinants of emerging PrEP inequities. In partnership with community key informants, we conducted a Rapid Ethnographic Assessment (REA) of multilevel PrEP use determinants among young Black gay and bisexual (YBGBM) men in the metropolitan Atlanta area to inform the development and coordination of local HIV programs.MethodsIn the assessment, we drew upon the perspectives of local clinicians, community-based organization leaders, health educators, and PrEP clients to identify barriers and facilitators to PrEP use among YBGBM through interviews (N = 23). Data were collected from September 2020 -to January 2021 and were analyzed through a staged deductive-inductive thematic analysis. The themes were later summarized and presented to community stakeholder participants to facilitate member-checking.ResultsOur analyses revealed structural, cultural, relationship, and developmental factors which shaped PrEP use. The most prominent being "ease of access to PrEP" (structural level), "provider support" (interpersonal), and "life-stage traits" (individual). Our results also contribute novel information concerning the axes of intersectional stigma (spatial, racial, sexual identity, and HIV) among YBGBM in Atlanta and its divergent effects on PrEP use.ConclusionIncreased PrEP use among YBGBM, particularly among those living in the south, is essential to ending the domestic HIV epidemic. Altogether, our results emphasize the need for PrEP program modifications, which increase flexibility in methods and modes of access and are culturally adapted to the needs of YBGBM. There is also a need for resources that holistically focus on mental health, trauma, and racism as critical components of support.

Objective: The objective of the study is to investigate which neurologic complications affect clinical outcomes the most following cervical deformity (CD) surgery. Methods: CD patients (C2-C7 Cobb >10°, CL >10°, cSVA >4 cm or chin-brow vertical angle >25°) >18 years with follow-up surgical and health-related quality of life (HRQL) data were included. Descriptive analyses assessed demographics. Neurologic complications assessed were C5 motor deficit, central neurodeficit, nerve root motor deficits, nerve sensory deficits, radiculopathy, and spinal cord deficits. Neurologic complications were classified as major or minor, then: intraoperative, before discharge, before 30 days, before 90 days, and after 90 days. HRQL outcomes were assessed at 3 months, 6 months, and 1 year. Integrated health state (IHS) for the neck disability index (NDI), EQ5D, and modified Japanese Orthopaedic Association (mJOA) were assessed using all follow-up time points. A subanalysis assessed IHS outcomes for patients with 2Y follow-up. Results: 153 operative CD patients were included. Baseline characteristics: 61 years old, 63% female, body mass index 29.7, operative time 531.6 ± 275.5, estimated blood loss 924.2 ± 729.5, 49% posterior approach, 18% anterior approach, 33% combined. 18% of patients experienced a total of 28 neurologic complications in the postoperative period (15 major). There were 7 radiculopathy, 6 motor deficits, 6 sensory deficits, 5 C5 motor deficits, 2 central neurodeficits, and 2 spinal cord deficits. 11.2% of patients experienced neurologic complications before 30 days (7 major) and 15% before 90 days (12 major). 12% of neurocomplication patients went on to have revision surgery within 6 months and 18% within 2 years. Neurologic complication patients had worse mJOA IHS scores at 1Y but no significant differences between NDI and EQ5D (0.003 vs. 0.873, 0.458). When assessing individual complications, central neurologic deficits and spinal cord deficit patients had the worst outcomes at 1Y (2.6 and 1.8 times worse NDI scores, P = 0.04, no improvement in EQ5D, 8% decrease in EQ5D). Patients with sensory deficits had the best NDI and EQ5D outcomes at 1Y (31% decrease in NDI, 8% increase in EQ5D). In a subanalysis, neurologic patients trended toward worse NDI and mJOA IHS outcomes (P = 0.263, 0.163). Conclusions: 18% of patients undergoing CD surgery experienced a neurologic complication, with 15% within 3 months. Patients who experienced any neurologic complication had worse mJOA recovery kinetics by 1 year and trended toward worse recovery at 2 years. Of the neurologic complications, central neurologic deficits and spinal cord deficits were the most detrimental.

Summary: Here, we present a step-by-step protocol for three-dimensional reconstruction of astrocyte morphology, applied to the central amygdala oxytocin receptor-expressing astrocytes. This includes RNAse-free perfusion, combination of RNAscope and immunohistochemistry, and confocal imaging. This protocol provides detailed information about tissue handling and a comprehensive description of the RNAScope technique to label rat and mouse oxytocin receptor mRNA. We also describe three-dimensional reconstruction that allows the assessment of more than 70 different cellular parameters, powerful for studying astrocyte morphology and astrocyte-astrocyte interactions.For complete details on the use and execution of this protocol, please refer to Wahis et al. (2021) and Althammer et al. (2020).

This report reflects on a follow-on initiative from the AHRC-funded project “Fifty Years of British Music Video” designed to explore a collaboration between Cuba’s dance, film, and music cultures to create non-performance-based dance videos. Facilitated by service company Island Pictures, we worked with a young director, Giselle Garcia Castro, dancers at Danza Contemporánea de Cuba, and leading Cuban rap artist Telmary. The result was a single-shot video for Telmary’s “Soy el Verso” (2018), filmed in the dance studio, based on an improvisation guided by Giselle, and inspired by the José Martí poem in the song. The video fulfilled PI Caston’s ambition to break down the barrier between “dance film” and “music video” by building the choreography from the lyrics and making it the centre of the exercise. It endorsed Caston’s conceptual aim to encourage practitioners to identify and articulate their own narrative and iconography. The team also produced a fifteen-minute documentary of the process including interviews with filmmakers, teachers and students. The project demonstrated that academic collaboration with artistic communities can stimulate new creative practices and economic development. It also showed how creative industries researchers can use networks established by institutions such as the British Council and British Embassies to exchange media practice.

Consider the following higher order difference equation \begin{equation*} x(n+1)= f(n,x(n))+g(n,x(n-k))+b(n), \qquad n=0, 1, \dots \end{equation*} where $f(n,x), g(n,x): \{0, 1, \dots \}\times [0, \infty) \rightarrow [0,\infty)$ are continuous functions in $x$ and periodic functions with period $\omega$ in $n$, $\{b(n)\}$ is a real sequence, and $k$ is a nonnegative integer. We show that under proper conditions, every nonnegative solution of the equation is quasi-periodic with period $\omega$. Applications to some other difference equations derived from mathematical biology are also given.

Abstract Background There is a paucity of literature regarding the implementation of enhanced recovery after surgery (ERAS) protocols for open lumbar spine fusions. We implemented an ERAS program for 1–2-level lumbar spine fusion surgery and identified areas that might benefit from perioperative interventions to improve patient satisfaction and outcomes. Methods This institutionally approved quality improvement (QI) ERAS program for lumbar spine fusion was designed for all neurosurgical patients 18 years and older scheduled for 1 or 2 level primary lumbar fusions. The ERAS bundle contained elements such as multimodal analgesia including preoperative oral acetaminophen and gabapentin, postoperative early mobilization and physical therapy, and a prophylactic multimodal antiemetic regimen to decrease postoperative nausea and vomiting. No fluid management or hemodynamic parameters were included. Pre-ERAS and post-ERAS data were compared with regard to potential confounders, compliance with the ERAS bundle, and postoperative outcomes. Results A total of 230 patients were included from October 2013 to May 2017. The pre-ERAS phase consisted of 123 patients, 11 patients during the transition period, and 96 serving as post-ERAS patients. The pre-ERAS and post-ERAS groups had comparable demographics and comorbidities. Compliance with preoperative and intraoperative medication interventions was relatively good (~ 80%). Compliance with postoperative elements such as early physical therapy, early mobilization, and early removal of the urinary catheter was poor with no significant improvement in post-ERAS patients. There was no significant change in the amount of short-acting opioids used, but there was a decrease in the use of long-acting opioids in the post-ERAS phase (14.6 to 5.2%, p = 0.025). Post-ERAS patients required fewer rescue antiemetic medications in the recovery room compared to pre-ERAS patients (40 to 24%). There was no significant difference in postoperative pain scores or hospital length of stay between the two groups. Conclusions Implementing an ERAS bundle for 1–2-level lumbar fusion had minimal effect in decreasing length of stay, but a significant decrease in postoperative opioid and rescue antiemetic use. This ERAS bundle showed mixed results likely secondary to poor ERAS protocol compliance. Going forward, this QI project will look to improve post-operative ERAS implementation to improve patient outcomes.

Consider the delay differential equation with a forcing term \[\tag{\(\ast\)} x'(t)=-f(t,x(t))+g(t,x(t-\tau ))+r(t), \quad t \geq 0\] where \(f(t,x): [0,\infty) \times [0,\infty) \to \mathbb{R}\), \(g(t,x): [0,\infty) \times [0,\infty) \to [0,\infty)\) are continuous functions and \(\omega\)-periodic in \(t\), \(r(t): [0,\infty) \to\mathbb{R}\) is a continuous function and \(\tau \in (0,\infty)\) is a positive constant. We first obtain a sufficient condition for the existence of a unique nonnegative periodic solution \(\tilde{x}(t)\) of the associated unforced differential equation of Eq. (\(\ast\)) \[\tag{\(\ast\ast\)} x'(t)=-f(t,x(t))+g(t,x(t-\tau)), \quad t \geq 0.\] Then we obtain a sufficient condition so that every nonnegative solution of the forced equation (\(\ast\)) converges to this nonnegative periodic solution \(\tilde{x}(t)\) of the associated unforced equation(\(\ast\ast\)). Applications from mathematical biology and numerical examples are also given.

Peer-led team learning (PLTL), specifically the model known as ‘Workshops’, has been shown to contribute positively and significantly to student success in STEM courses across subjects (Gosser et al., 2001). Our research adds to the SOTL literature describing the effectiveness of Workshops by reporting on the changes in student leaders. We examine the level to which leaders acquired new skills in effective teaching and describe the pedagogical interactions in the groups they led as a result of the combination of training and experience facilitating first-year Calculus Workshop sections. This was a semester-long study on twenty-two Workshop leaders for two multi-section, introductory calculus courses at a small research university. Our method is a novel overlay of two metrics that allows, with some forethought, a robust analysis of Workshop leader outcomes that would complement any assessment of PLTL implementation faculty might choose to undertake.

Protocatechuic acid, or 3,4-dihydroxybenzoic acid, is produced by both soil and marine bacteria in the free form and as the iron binding component of the siderophore petrobactin. The soil bacterium, Bacillus thuringiensis kurstaki ATCC 33679, contains the asb operon, but does not produce petrobactin. Iron restriction resulted in diminished B. thuringiensis kurstaki ATCC 33679 growth and the production of catechol(s). The gene product responsible for protocatechuic acid (asbF) and its receptor (fatB) were expressed during stationary phase growth. Gene expression varied with growth temperature, with optimum levels occurring well below the Bacillus anthracis virulence temperature of 37 °C. Regulation of protocatechuic acid suggests a possible role for this compound during soil growth cycles.

The most severe complication of yttrium-90 therapy is gastrointestinal ulceration caused by extrahepatic dispersion of microspheres. Standard pretreatment planning requires extensive angiographic evaluation of the hepatic circulation and embolization of hepatoenteric collaterals; however, in patients with severe renal insufficiency, this evaluation may lead to acute renal failure. In order to minimize iodinated contrast utilization in a patient with preexisting severe renal insufficiency, the authors describe the use of a balloon catheter for temporary occlusion of the common hepatic artery to induce transient redirection of flow of the hepatoenteric arteries towards the liver, in lieu of conventional coil embolization.

ABSTRACT Objective: To develop a version of the Lumbar Stiffness Disability Index (LSDI), translated into Portuguese and culturally adapted for the Brazilian population. Methods: The well-established process of translation into Portuguese and back translation into English was used together with cultural adaptation. Results: Five bilingual translators (English and Portuguese) performed the translation of the Lumbar Stiffness Disability Index (LSDI) from English to Portuguese based on interactive discussions used to arrive at a consensus translation. The translated version of LSDI was then translated into English by a native English-speaking translator who did not know the concepts involved in LSDI. The original LSDI and back translation were compared by a committee formed by the translators responsible for translating the original into Portuguese and a North-American spine surgeon, and because they were considered equivalent, the final version of the LSDI translated into Portuguese and culturally adapted was defined. Conclusions: In order to facilitate global and cross-cultural comparisons of the influence of lumbar stiffness related to spinal arthrodesis in daily activities, this study presents a version of LSDI that has been translated into Portuguese and culturally adapted for the Brazilian population. Level of Evidence; Not Applicable. Prospective Study.