We report the synthesis and characterization of a series of polyanilines (PANI) that are templated with a polymer acid at varying molecular weights. The polymer acid template of choice, poly(2-acrylamido-2-methyl-1-propanesulfonic acid), or PAAMPSA, was synthesized via conventional free-radical polymerization with molecular weights ranging from 45 kg mol 21 to 724 kg mol 21 . Subsequent aniline polymerization in the presence of PAAMPSA yielded waterdispersible, conductive PANI-PAAMPSA. The electrical conductivity of PANI-PAAMPSA increases by approximately three-fold with decreasing PAAMPSA molecular weight. This trend is accompanied by significant structural changes, including increases in PANI crystallinity and conjugation length. These conductivities (0.4-1.1 S cm 21 ) exceed the highest reported for polymer acid-doped PANI systems.

Developing information technology to democratize scientific knowledge and support citizen empowerment is a challenging task. In our case, a local community suffered from air pollution caused by industrial activity. The residents lacked the technological fluency to gather and curate diverse scientific data to advocate for regulatory change. We collaborated with the community in developing an air quality monitoring system which integrated heterogeneous data over a large spatial and temporal scale. The system afforded strong scientific evidence by using animated smoke images, air quality data, crowdsourced smell reports, and wind data. In our evaluation, we report patterns of sharing smoke images among stakeholders. Our survey study shows that the scientific knowledge provided by the system encourages agonistic discussions with regulators, empowers the community to support policy making, and rebalances the power relationship between stakeholders.

[1] New 46.8/430 MHz (V/UHF) radar meteor observations at Arecibo Observatory reveal many previously unreported features in the radar meteor return that are consistent with meteoroid fragmentation. These signature featuresobserved at both V/UHF-include strong intra-pulse and pulse-to-pulse fading as the result of interference between or among multiple meteor head-echo returns and between head-echo and impulsive "flare" event "trail-echoes". A few events are suggestive of differential ablation. These V/ UHF radar observations are particularly useful as coaxial beams enable common volume observations that remove much ambiguity in the interpretation of the observations in terms of meteoroid fragmentation. These results, combined with simple modeling and two 500 sample statistical studies, lead us to conclude that a majority of the ∼17,000 AO radar meteor events included in this study exhibit fragmentation-manifested as non-uniform lightcurvesimplying that the form of meteoroid mass flux into the upper atmosphere goes well beyond simple ablation.

CD44 is expressed on T cells where its ability to bind hyaluronan is tightly regulated. Here, we investigated when T cells bind hyaluronan during an immune response. We found that naïve, murine T cells do not bind fluoresceinated hyaluronan but are induced to bind upon antigen-induced T-cell activation in vitro and in vivo. Hyaluronan binding occurred on proliferating T cells and the percentage of hyaluronan-binding cells correlated with the strength of the activation stimulus. A small percentage of hyaluronan-binding cells persisted after in vitro activation and had a memory phenotype (CD122(+) CD44(hi)). This hyaluronan-binding population increased after culture with IL-7 or IL-15 and proliferated more rapidly than nonbinding cells. In vivo, approximately 20-30% of antigen-specific OT-I CD8(+) memory T cells in the spleen and BM bound hyaluronan. Hyaluronan binding identified memory cells that proliferated faster in IL-7 and IL-15, and enriched for CD62L(+) central memory cells. In vivo homeostatic proliferation induced hyaluronan binding on a small percentage of the most rapidly dividing cells after several cell divisions. This study demonstrates that hyaluronan binding is induced upon antigen-induced T-cell activation and occurs on a percentage of the most proliferative activated and memory T cells.

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