Environmental plastics in the context of UV radiation, climate change, and the Montreal Protocol.

There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.

Plastics in the environment in the context of UV radiation, climate change and the Montreal Protocol: UNEP Environmental Effects Assessment Panel, Update 2023.

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.

Evaluation of an interprofessional naloxone didactic and skills session with medical residents and physician assistant learners.

BACKGROUND: The CDC has reported 399,230 opioid-related deaths from 1999-2017. In 2018, the US surgeon general issued a public health advisory, advising all Americans to carry naloxone. Studies show that enhanced naloxone access directly reduces death from opioid overdose. Despite this, health care professional learners report low knowledge and confidence surrounding naloxone. Therefore, it becomes critical that medical education programs incorporate didactic and experiential sessions improving knowledge, skills and attitudes regarding harm reduction through naloxone. OBJECTIVES: 1. Describe the components and evaluation of a replicable and adaptable naloxone didactic and skills session model for medical providers; 2. Report the results of the evaluation from a pilot session with family medicine residents and physician assistant students; and 3. Share the session toolkit, including evaluation surveys and list of materials used. METHODS: In July 2017, a literature search was completed for naloxone skill training examining best practices on instruction and evaluation. A training session for family medicine residents and physician assistant learners was designed and led by University of Cincinnati College of Medicine and College of Pharmacy faculty. The same faculty designed a pre and post session evaluation form through internal review on elements targeting naloxone knowledge, attitude, and self-efficacy. RESULTS: The training session included one hour for a didactic and one hour for small group live skills demonstration in four methods of naloxone administration (syringe and ampule, nasal atomizer, branded nasal spray and auto injector). Forty-eight participants showed statistically significant (p<0.05) improvement in knowledge (67.5% to 95.9%), attitudes (71.2% to 91.2%), and self-efficacy (62.1% to 97.8%) from pre to post assessment. Forty-four of 48 participants agreed that the pace of the training was appropriate and that the information will be of use in their respective primary care practices. Supply costs for the session were USD 1,200, with the majority being reusable on subsequent trainings. CONCLUSIONS: Our study of a naloxone didactic and skills session for primary care trainees demonstrated significant improvements in knowledge, self-efficacy, and attitudes. It provides an adaptable and efficient model for delivery of knowledge and skills in naloxone administration training. The pilot data suggest that the training was efficacious.

Exposure study on UV-induced degradation of PTFE and ceramic optical diffusers.

We report on a study of the ultraviolet (UV)-induced degradation on optical grade polytetrafluoroethylene (PTFE) and ceramic diffuser samples. Long-term UV exposure may significantly alter the reflectance and lead to an error in the calibration of optical instruments. A large integrating sphere was used to irradiate the samples for 334.7 days at an irradiance level of 194.9 W/m2. Samples were qualified and measured for reflectance factor, bidirectional reflectance distribution function, and fluorescence, before and after the exposure, and at 12-week intervals during the exposure. This study revealed significant differences between the aging behavior of ceramic and PTFE samples.

Quantitative Rheometry of Thin Soft Materials Using the Quartz Crystal Microbalance with Dissipation.

In the inertial limit, the resonance frequency of the quartz crystal microbalance (QCM) is related to the coupled mass on the quartz sensor through the Sauerbrey expression that relates the mass to the change in resonance frequency. However, when the thickness of the film is sufficiently large, the relationship becomes more complicated and both the frequency and damping of the crystal resonance must be considered. In this regime, a rheological model of the material must be used to accurately extract the adhered film's thickness, shear modulus, and viscoelastic phase angle from the data. In the present work we examine the suitability of two viscoelastic models, a simple Voigt model ( Physica Scripta 1999, 59, 391-396) and a more realistic power-law model ( Langmuir 2015, 31, 4008-4017), to extract the rheological properties of a thermoresponsive hydrogel film. By changing temperature and initial dry film thickness of the gel, the operation of QCM was traversed from the Sauerbrey limit, where viscous losses do not impact the frequency, through the regime where the QCM response is sensitive to viscoelastic properties. The density-shear modulus and the viscoelastic phase angle from the two models are in good agreement when the shear wavelength ratio, d/λ n, is in the range of 0.05-0.20, where d is the film thickness and λ n is the wavelength of the mechanical shear wave at the nth harmonic. We further provide a framework for estimating the physical properties of soft materials in the megahertz regime by using the physical behavior of polyelectrolyte complexes. This provides the user with an approximate range of allowable film thicknesses for accurate viscoelastic analysis with either model, thus enabling better use of the QCM-D in soft materials research.

Paralytic ileus requiring hospitalization secondary to high-dose antipsychotic polypharmacy and benztropine.

Ileus can result from the combined activity of antipsychotic and anticholinergic medications. Despite frequent use, case reports in the literature are sparse. We present a patient who developed a paralytic ileus requiring extended hospitalization. Providers should minimize antipsychotic and concurrent anticholinergic medications, consider prophylactic bowel regimens and monitor for constipation.

On the origins of sudden adhesion loss at a critical relative humidity: examination of bulk and interfacial contributions.

The origins for abrupt adhesion loss at a critical relative humidity (RH) for polymeric adhesives bonded to inorganic surfaces have been explored using a model poly(methyl methacrylate) (PMMA) film on glass. The interfacial and bulk water concentrations within the polymer film as a function of D 2O partial pressure were quantified using neutron reflectivity. Adhesion strength of these PMMA/SiO 2 interfaces under the same conditions was quantified using a shaft loaded blister test. A drop in adhesion strength was observed at a critical RH, and at this same RH, a discontinuity in the bulk moisture concentration occurred. The moisture concentration near the interface was higher than that in the bulk PMMA, and at the critical RH, the breadth of the interfacial water concentration distribution as a function of distance from the SiO 2/PMMA interface increased dramatically. We propose a mechanism for loss of adhesion at a critical RH based upon the interplay between bulk swelling induced stress and weakening of the interfacial bond by moisture accumulation at the PMMA/SiO 2 interface.

Reduced vascular complications after percutaneous coronary interventions with a nonmechanical suture device: results from the randomized RACE study.

The objective of this study was to evaluate the safety and efficacy of a novel nonmechanical percutaneous suture device, X-Press, after diagnostic catheterization and percutaneous coronary interventions (PCIs) in the setting of glycoprotein IIb/IIIa inhibitor usage. Current percutaneous vascular suture devices remain mechanically complex and expensive and have not been shown to reduce major vascular complications. Using a 2:1 randomization scheme (2:1 ratio, device vs. compression), 393 patients undergoing diagnostic catheterization (n = 133) or PCI (n = 260) were randomized in the prospective Rapid Ambulation After Closure (RACE) study and evaluated for time to ambulation, time to hemostasis, treatment success, and incidence of major vascular complications. Glycoprotein IIb/IIIa inhibitors were used in 52% of PCI patients. There was a significant reduction in the primary efficacy endpoint of median time to ambulation for device compared to control with both diagnostic (2.2 vs. 6.2 hr; P = 0.0001) and PCI patients (4.1 vs. 14.7 hr; P = 0.0001). Device malfunction occurred in 3.1% patients without clinical sequalae. Equivalence in the primary safety endpoint, the incidence of major complications (vascular repair, ultrasound-guided compression, transfusion, or infection) at 14 days, was observed with the X-Press device (1/261; 0.4%) compared to control (3/132; 2.3%; P = 0.11). In PCI patients, half of whom received glycoprotein IIb/IIIa inhibitors, there was a significant reduction in the incidence of vascular complications in patients using the device (0/172; 0%) compared to control (3/88; 3.4%; P = 0.037). In diagnostic catheterization and PCI, a novel nonmechanical suture device reduced the time to ambulation and demonstrated equivalence in major complications compared to conventional compression techniques. The incidence of major complications after PCI was reduced with the device.