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There is an urgent need for low-cost and simple-to-use tools for identifying substandard and falsified medicines. In this work we demonstrate “Disintegration Fingerprinting” (DF), a technique that identifies pills, tablets, caplets, and other solid-dosage drugs based on how the drug disintegrates and dissolves in liquid. The DF hardware consists of a water-filled transparent plastic cup atop a conventional magnetic stirrer. An inexpensive sensor mounted on the outside of the cup shines infrared light into the cup and measures the amount of light that is reflected back to the sensor. When a pill is added to the stirred water, the pill begins to disintegrate into particles that swirl around inside the cup. Whenever one of these particles passes near the infrared sensor, the particle reflects additional light back to the sensor and creates a millisecond-duration peak in a plot of sensor output vs. time. The number of particles in the water changes over time as the particles continue to disintegrate and (in some cases) eventually dissolve away. By plotting the number of particles detected vs. time, we create a Disintegration Fingerprint that can be used to identify the drug product. In a proof-of-concept study, we used DF to analyze 96 pills from 32 different drug products (including antibiotics, opioid and non-opioid analgesics, antidepressants, anti-inflammatories, antiemetics, antihistamines, decongestants, muscle relaxants, expectorants, sleep aids, cold medicines, antacids, hormonal birth control, and dietary supplements, as well as a simulated falsified drug product). We found that DF correctly identified 90% of these pills, and the technique can even distinguish name-brand and generic versions of the same drug. By providing a fast (60-minute), inexpensive ($33 USD), and easy-to-use tool for identifying substandard and falsified medicines, Disintegration Fingerprinting can play an important role in the fight against fake drugs.more » « lessFree, publicly-accessible full text available August 19, 2026
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There has been growing recognition of the importance of engaging communities in environmental health research. Among the various methods of community-engaged research, one approach is to work with community ambassadors – people who are active and well connected in their communities – to facilitate scientists’ interactions with community members. Drawing on our own experiences as community ambassadors in the WellHome Study, an investigation of indoor air quality in West London, UK, we offer 3 key insights to scientists interested in this model of community-engaged research. We argue, first, that community ambassadors can help scientists build trust and engage research participants. Second, we note the value of fully integrating community ambassadors into a project team and present suggestions for how this may be accomplished. Third, we underscore the importance of remunerating community ambassadors and the need for careful reflection on the amount and form of compensation. While much has been written about the advantages and challenges of community-engaged research, this commentary brings the voice of community members to the fore of these discussions. It highlights how the community ambassador model can bring mutual benefits, furthering research goals while also providing a meaningful experience for community members.more » « less
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This study examines biodegradability (BD) and optimum conditions for the solid-state anaerobic digestion (SS-AD) of organic solid poultry waste (organs, intestines, offal, and unprocessed meat) to maximize biomethane production. Three main parameters, substrate-to-inoculum (S/I) ratio, pH, and temperature, were evaluated for the SS-AD of organic solid poultry waste. pH was evaluated at non-adjusted pH, initially adjusted pH, and controlled pH conditions at a constant S/I ratio of 0.5 and temperature of 35 ± 1 °C. The S/I ratios were examined at (0.3, 0.5, 1, and 2) at a controlled pH of ≈7.9 and temperature of 35 ± 1 °C. The temperature was assessed at mesophilic (35 ± 1 °C) and thermophilic (55 ± 1 °C) conditions with a constant S/I ratio of 0.5 and controlled pH of ≈7.9. The results demonstrate that the highest biomethane production and BD were achieved with a controlled pH of ≈7.9 (689 ± 10 mg/L, 97.5 ± 1.4%). The initially adjusted pH (688 ± 14 mg/L, 97.3 ± 1.9%) and an S/I ratio of 0.3 (685 ± 8 mg/L, 96.8 ± 1.2%) had approximately equivalent outcomes. The thermophilic conditions yielded 78% lower biomethane yield than mesophilic conditions. The challenge of lower biomethane yield under thermophilic conditions will be resolved in future studies by determining the rate-limiting step. These observations highlight that SS-AD is a promising technology for biomethane production from solid organic poultry waste.more » « lessFree, publicly-accessible full text available July 1, 2026
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Free, publicly-accessible full text available May 6, 2026
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Free, publicly-accessible full text available June 13, 2026
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Abstract On 4 February 1976, a Mw 7.5 earthquake along the Motagua fault, Guatemala, ruptured ~230 km of the North American and Caribbean plate boundary. Today, the plate boundary remains poorly monitored, and the 1976 earthquake is still not fully understood. Here, we present seismic reflection profiles and radiometrically dated sediment core data from six lakes around the Motagua fault, together with reports of destruction and a quasi-dynamic rupture model, which show that the 1976 earthquake experienced strong directivity that impacted the distribution of shaking. The earthquake left behind a detailed record of event deposits (EDs) in five of the six study lakes. Thicker EDs are present in Lake Atitlán, near the terminus of the earthquake rupture, whereas thinner EDs were found in lakes off-axis of the rupture direction. We argue that EDs can be utilized to constrain asymmetrical distribution of shaking during earthquakes and that paleoseismic studies should consider directivity as a factor controlling the thickness of EDs.more » « lessFree, publicly-accessible full text available September 10, 2026
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Free, publicly-accessible full text available June 9, 2026
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Free, publicly-accessible full text available May 6, 2026
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Free, publicly-accessible full text available May 1, 2026
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Free, publicly-accessible full text available May 1, 2026
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