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Over the course of the past two decades, attrition within the US governmental public health workforce has passed concerning and become dire. The practice sector has struggled to recruit and retain new talent, despite the infusion of considerable federal investment in workforce expansion initiatives. In 2020, Emory University's Rollins School of Public Health partnered with the Georgia Department of Public Health to establish the Rollins Epidemiology Fellowship Program. Initially created to recruit and place early-career master of public health-level epidemiologists into Georgia's public health system for COVID-19 pandemic response, the two-year service-learning program has evolved into an effective and replicable model of direct academic involvement in strengthening the governmental public health workforce. Here we describe the program's structure and early results, spotlighting it for consideration by the federal government and other jurisdictions interested in directly engaging academia in efforts to revitalize the public health workforce.

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Lung biopsies are often used to aid in the diagnosis of cancers. However, the procedure carries the dual risk of air (pneumothorax) or blood (hemothorax) filling the pleural cavity, increasing the risk of a collapsed lung and chest intubation. This work demonstrates the effectiveness of a polyurethane-based shape memory polymer foam as a biopsy tract sealant. The impact of diameter, length, pore size, and shape memory effect was evaluated to determine the ideal device design for tract sealing. Characterization in an in vitro benchtop lung model identified that diameter had the largest influence on sealing efficacy, while the length of the device had little to no impact. Finally, evaluation of deployment force demonstrated that devices fabricated from the shape memory polymer foams were easier to deploy than elastic foams. Following characterization, down-selected device designs were combined with radiopaque markers for use in image-guided based procedures. Furthermore, the introduction of the markers or sterilization did not impact the ability of the devices to seal the biopsy tract and led to a decrease in the deployment force. Overall, these results demonstrate the potential for polyurethane-based shape memory foam devices to serve as biopsy tract sealant devices that aim to reduce complications, such as pneumothorax, from occurring.

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AIMS: To evaluate the association of physical activity (PA) with atrial fibrillation (AF) incidence in an elderly population. METHODS: We studied 5166 participants of the Atherosclerosis Risk in Communities cohort examined in 2011-2013 free of AF. Self-reported PA was evaluated with a validated questionnaire. Weekly minutes of leisure-time moderate to vigorous physical activity (MVPA) were calculated and categorized using the 2018 Physical Activity Guidelines for Americans (no activity [0 min/week], low [> 0- < 150 min/week], adequate [150- < 300 min/week], high [≥ 300 min/week]). Incident AF through 2019 was ascertained from hospital discharges and death certificates. Cox models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for AF by levels of physical activity adjusting for potential confounders. RESULTS: The mean (SD) age for the sample was 75 (5) years (59% female, 22% Black). During a mean (SD) follow-up time of 6.3 (2.0) years, 703 AF events were identified. The association of MVPA with AF incidence showed a U-shaped relationship. Compared to those not engaging in MVPA, individuals with low MVPA had a 23% lower hazard of AF (HR = 0.77; 95% CI 0.61, 0.96), while those with adequate MVPA had a 14% lower hazard (HR 0.86; 95% CI 0.69, 1.06). High levels of MVPA were not associated with AF risk (HR 0.97; 95% CI 0.78, 1.20). CONCLUSION: This study suggests that being involved in low to moderate levels of MVPA is associated with lower AF risk, with no evidence of increased risk of AF in those with higher levels of MVPA.

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The ability to treat complex medical issues often requires dynamic and versatile materials. Electrospinning is a fabrication technique which produces nano-/microfibers that can mimic the extracellular matrix of many biological tissues while shape memory polymers allow for geometric changes in devices upon implantation. Here, we present the fabrication of electrospun polyurethane which exhibits the shape memory effect. To improve the mechanical and shape memory properties of this system, we incorporate vinyl side chains in the polymer backbone which enable crosslinking via thiol-ene click chemistry post fabrication. We also discuss a novel technique to improve photoinitiated crosslinking for electrospun materials. A material with these properties is potentially beneficial for various medical applications, such as vascular anastomosis, and the characterization of this material will be valuable in directing those applications.

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Shape memory polymer foams have been used in a wide range of medical applications, including, but not limited to, vessel occlusion and aneurysm treatment. This unique polymer system has been proven to shape-fill a void, which makes it useful for occlusion applications. While the shape memory polymer foam has superior performance and healing outcomes compared to its leading competitors, some device applications may benefit from longer material degradation times, or degradation-resistant formulations with increased fibrous encapsulation. In this study, biostable shape memory polymer foams were synthesized, and their physical and chemical properties were characterized as an initial evaluation of feasibility for vascular occlusion applications. After characterizing their shape memory behavior in an aqueous environment, degradation of this polymer system was studied in vitro using accelerated oxidative and hydrolytic solutions. Results indicated that the foams did not lose mass under oxidative or hydrolytic conditions, and they maintained high shape recovery in aqueous in vitro models. These degradation-resistant systems have potential for use in vascular occlusion and other wound healing applications that benefit from permanent, space-filling shape memory behavior.

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The goal of this work was to develop a shape memory polymer (SMP) foam with visibility under both X-ray and magnetic resonance imaging (MRI) modalities. A porous polymeric material with these properties is desirable in medical device development for applications requiring thermoresponsive tissue scaffolds with clinical imaging capabilities. Dual modality visibility was achieved by chemically incorporating monomers with X-ray visible iodine-motifs and MRI visible monomers with gadolinium content. Physical and thermomechanical characterization showed the effect of increased gadopentetic acid (GPA) on shape memory behavior. Multiple compositions showed brightening effects in pilot, T1-weighted MR imaging. There was a correlation between the polymeric density and X-ray visibility on expanded and compressed SMP foams. Additionally, extractions and indirect cytocompatibility studies were performed to address toxicity concerns of gadolinium-based contrast agents (GBCAs). This material platform has the potential to be used in a variety of medical devices.

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Shape memory polymer (SMP) foams are a promising material for hemostatic dressings due to their biocompatibility, high surface area, excellent shape recovery, and ability to quickly initiate blood clotting. Biodegradable SMP foams could eliminate the need for a secondary removal procedure of hemostatic material from the patients' wound, further facilitating wound healing. In this study, we developed hydrolytically and oxidatively biodegradable SMP foams by reacting polyols (triethanolamine or glycerol) with 6-aminocaproic acid or glycine to generate foaming monomers with degradable ester bonds. These monomers were used in foam synthesis to provide highly crosslinked SMP foam structures. The ester-containing foams showed clinically relevant thermal properties that were comparable to controls and excellent shape recovery within eight min. Triethanolamine-based ester-containing foams showed interconnected porous structure along with increased mechanical strength. Faster hydrolytic and oxidative biodegradation rates were achieved in ester-containing foams in comparison to controls. These biodegradable SMP foams with clinically applicable thermal properties possess great potential as an effective hemostatic device for use in hospitals or on battlefields.

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We employ a concentric sphere Mie scattering model to describe light scattering by pulmonary alveoli and airway surface liquid (ASL). Using this layered sphere model, we compare alveolar scattering at different points along the respiratory cycle and observe the effect of ASL thickness on light scattering in the lung. We have also extrapolated the model to investigate alveolar scattering in various animal models of pulmonary disease. This model of pulmonary light scattering can estimate in vivo optical properties for normal and pathological states, potentially aiding the design of optical systems for diagnosis and investigation of pulmonary pathologies.

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Despite a number of clinically available hemostats, uncontrolled bleeding is the primary cause of trauma-related death. Shape-memory polymer (SMP) foams have a number of desirable properties for use as hemostats, including shape recovery to enable delivery into bleed sites, biocompatibility, and rapid blood clotting. To expand upon this material system, the current work aims to incorporate phenolic acids, which are honey-based antimicrobial agents, into SMP foams. We showed that cinnamic acid (CA) can be utilized as a monomer in SMP synthesis to provide foams with comparable pore structure and retained cytocompatibility. The addition of CA enabled tuning of thermal and shape-memory properties within clinically relevant ranges. Furthermore, the modified foams demonstrated initial and sustained antimicrobial effects against gram-positive and gram-negative bacteria. These multifunctional scaffolds demonstrate potential for use as hemostats to improve upon current hemorrhage treatments and provide a new tool in tuning the biological and material properties of SMP foams.

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OBJECTIVE: Interventions to support healthy gestational weight gain are often ineffective. The objective was to develop a model of how pregnant Latinas-who have a higher risk of poor maternal and neonatal weight-related outcomes-conceptualize healthy gestational weight gain, providing guidance for future interventions. METHOD: Ten focus groups with 50 pregnant Latinas were conducted by a native Spanish-speaking female moderator. On the basis of participant responses, we used grounded theory to inductively develop a personal conceptual framework for gestational weight gain. RESULTS: Commonly identified barriers to being active and healthy eating included negative emotions, body image, physical discomfort, low energy, and lack of motivation. Women identified sociocultural issues such as a sense of isolation from family (among immigrants) and the degree of perceived social support as important contributors to health behaviors. Two personal health schemas emerged from participant responses. The "mother-child health schema" describes the degree to which participants recognized the interrelatedness of health needs for baby and for themselves. The "attention to gestational weight gain schema" describes how a respondent's attention to and perceived importance of gestational weight gain influences health-related behaviors during pregnancy. CONCLUSIONS: Women's sociocultural and interpersonal context influence weight-related behaviors through the lens of personal health schemas. Understanding how cognitive aspects relate to traditional behavioral determinants suggests several opportunities for intervention, such as focusing on healthy behaviors instead of numerical targets for healthy weight gain. Although derived from Spanish-speaking Latin-American women, these results may also be potential leverage points for other minority groups. (PsycINFO Database Record

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Highly porous, open-celled shape memory polymer (SMP) foams are being developed for a number of vascular occlusion devices. Applications include abdominal aortic and neurovascular aneurysm or peripheral vascular occlusion. A major concern with implanting these high surface area materials in the vasculature is the potential to generate unacceptable particulate burden, in terms of number, size, and composition. This study demonstrates that particulate numbers and sizes in SMP foams are in compliance with limits stated by the most relevant standard and guidance documents. Particulates were quantified in SMP foams as made, postreticulation, and after incorporating nanoparticles intended to increase material toughness and improve radiopacity. When concentrated particulate treatments were administered to fibroblasts, they exhibited high cell viability (100%). These results demonstrate that the SMP foams do not induce an unacceptable level of risk to potential vascular occlusion devices due to particulate generation.

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To investigate the delivery of hydrophobic therapeutic agents, a novel class of interpenetrating networks (IPNs) were synthesized and composed of two networks: methacrylic acid grafted with poly(ethylene glycol) tethers, P(MAA-g-EG), and poly(n-butyl acrylate) (PBA). The hydrophilic P(MAA-g-EG) networks are pH-responsive hydrogels capable of triggered release of an encapsulated therapeutic agent, such as a low molecular weight drug or a protein, when it passes from the stomach (low pH) to upper small intestine (neutral pH). PBA is a hydrophobic homopolymer that can affect the IPN swelling behavior, the therapeutic agent loading efficiencies in IPNs, and solute release profiles from IPNs. In dynamic swelling conditions, IPNs had greater swelling ratios than P(MAA-g-EG), but in equilibrium swelling conditions the IPN swelling ratio decreased with increasing PBA content. Loading efficiencies of the model therapeutic agent fluorescein ranged from 21 - 44%. Release studies from neat P(MAA-g-EG) and the ensuing IPNs indicated that the transition from low pH (2.0) to neutral pH (7.0) triggered fluorescein release. Maximum fluorescein release depended on the structure and hydrophilicity of the carriers used in these studies.

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Brosnan and de Waal [Nature 425:297-299, 2003] reported that capuchin monkeys responded negatively to unequal reward distributions between themselves and another individual when comparing their own rewards with that of their partner. It was suggested that social emotions provided the underlying motivation for such behavior and that this inequity aversion is specific to the social domain. However, alternative hypotheses such as the "frustration effect" or the "food expectation hypothesis" may provide more parsimonious explanations for Brosnan and de Waal's [Nature 425:297-299] results, while others have argued that these findings are not congruent with the Fehr-Schmidt inequity aversion model cited by the authors. The claim that inequity aversion behavior is specific to the social domain has also been questioned, as primates also develop expectations about rewards in the absence of partners, and react negatively when those expectations are violated. In this study, a modified Dictator game was used to investigate whether capuchins would exhibit either disadvantageous inequity aversion behavior or reference-dependent expectancy violation in social and nonsocial conditions, respectively. When given the choice between an equitable and an inequitable outcome, the subjects showed disadvantageous inequity aversion behavior, choosing the equitable outcome significantly more in the social condition. In the nonsocial condition, however, subjects did not show negative expectancy violation resulting from the formation of reference-dependent expectations, choosing the equitable outcome at chance levels. These results suggest that capuchins attend to differential payoffs and that they are averse to inequity, which is disadvantageous to themselves.

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