University of Massachusetts Boston

About: University of Massachusetts Boston is a education organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Health care. The organization has 6541 authors who have published 12918 publications receiving 411731 citations. The organization is also known as: UMass Boston.

An optically pumped 2.5 μm GeSn laser on Si operating at 110 K

Abstract: This paper reports the demonstration of optically pumped GeSn edge-emitting lasers grown on Si substrates The whole device structures were grown by an industry standard chemical vapor deposition reactor using the low cost commercially available precursors SnCl4 and GeH4 in a single run epitaxy process Temperature-dependent characteristics of laser-output versus pumping-laser-input showed lasing operation up to 110 K The 10 K lasing threshold and wavelength were measured as 68 kW/cm2 and 2476 nm, respectively Lasing characteristic temperature (T0) was extracted as 65 K

The Impact of Emotional Tone, Message, and Broadcast Parameters in Youth Anti-smoking Advertisements

Abstract: Objectives. In the context of controversy regarding the optimal characteristics of anti-smoking advertisements for youth, this study examines the impact on recall and perceived effectiveness of variations in the message, emotional tone, reach and frequency of broadcast, remoteness of broadcast, and characteristics of the adolescent audience such as changes in smoking behavior, ownership of cigarette promotional items, and demographic variables. Method. A two-wave longitudinal survey of a population-based sample of 618 Massachusetts youth 12 to 15 years old was carried out in 1993 and 1997. A Generalized Estimating Equation (GEE) approach was used to model the recall and perceived effectiveness of eight advertisements as a function of viewer and ad characteristics. Results. Advertisements featuring messages about serious health consequences which had been independently rated as high in negative emotion were more likely to be recalled and were perceived as more effective by youth survey respondents than ads...

Topographical Mapping of the Rainbow Trout (Oncorhynchus mykiss) Microbiome Reveals a Diverse Bacterial Community with Antifungal Properties in the Skin

Abstract: The mucosal surfaces of wild and farmed aquatic vertebrates face the threat of many aquatic pathogens, including fungi. These surfaces are colonized by diverse symbiotic bacterial communities that may contribute to fight infection. Whereas the gut microbiome of teleosts has been extensively studied using pyrosequencing, this tool has rarely been employed to study the compositions of the bacterial communities present on other teleost mucosal surfaces. Here we provide a topographical map of the mucosal microbiome of an aquatic vertebrate, the rainbow trout (Oncorhynchus mykiss). Using 16S rRNA pyrosequencing, we revealed novel bacterial diversity at each of the five body sites sampled and showed that body site is a strong predictor of community composition. The skin exhibited the highest diversity, followed by the olfactory organ, gills, and gut. Flectobacillus was highly represented within skin and gill communities. Principal coordinate analysis and plots revealed clustering of external sites apart from internal sites. A highly diverse community was present within the epithelium, as demonstrated by confocal microscopy and pyrosequencing. Using in vitro assays, we demonstrated that two Arthrobacter sp. skin isolates, a Psychrobacter sp. strain, and a combined skin aerobic bacterial sample inhibit the growth of Saprolegnia australis and Mucor hiemalis, two important aquatic fungal pathogens. These results underscore the importance of symbiotic bacterial communities of fish and their potential role for the control of aquatic fungal diseases.

Turning on the Protonation-First Pathway for Electrocatalytic CO2 Reduction by Manganese Bipyridyl Tricarbonyl Complexes

Abstract: Electrocatalytic reduction of CO2 to CO is reported for the complex, {fac-MnI([(MeO)2Ph]2bpy)(CO)3(CH3CN)}(OTf), containing four pendant methoxy groups, where [(MeO)2Ph]2bpy = 6,6′-bis(2,6-dimethoxyphenyl)-2,2′-bipyridine. In addition to a steric influence similar to that previously established [Sampson, M. D. et al. J. Am. Chem. Soc. 2014, 136, 5460−5471] for the 6,6′-dimesityl-2,2′-bipyridine ligand in [fac-MnI(mes2bpy)(CO)3(CH3CN)](OTf), which prevents Mn0–Mn0 dimerization, the [(MeO)2Ph]2bpy ligand introduces an additional electronic influence combined with a weak allosteric hydrogen-bonding interaction that significantly lowers the activation barrier for C–OH bond cleavage from the metallocarboxylic acid intermediate. This provides access to the thus far elusive protonation-first pathway, minimizing the required overpotential for electrocatalytic CO2 to CO conversion by Mn(I) polypyridyl catalysts, while concurrently maintaining a respectable turnover frequency. Comprehensive electrochemical and comp...