85 research outputs found

    Store-directed price promotions and communications strategies improve healthier food supply and demand: impact results from a randomized controlled, Baltimore City store-intervention trial

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    Abstract Objective Small food store interventions show promise to increase healthy food access in under-resourced areas. However, none have tested the impact of price discounts on healthy food supply and demand. We tested the impact of store-directed price discounts and communications strategies, separately and combined, on the stocking, sales and prices of healthier foods and on storeowner psychosocial factors. Design Factorial design randomized controlled trial. Setting Twenty-four corner stores in low-income neighbourhoods of Baltimore City, MD, USA. Subjects Stores were randomized to pricing intervention, communications intervention, combined pricing and communications intervention, or control. Stores that received the pricing intervention were given a 10–30 % price discount by wholesalers on selected healthier food items during the 6-month trial. Communications stores received visual and interactive materials to promote healthy items, including signage, taste tests and refrigerators. Results All interventions showed significantly increased stock of promoted foods v . control. There was a significant treatment effect for daily unit sales of healthy snacks ( β =6·4, 95 % CI 0·9, 11·9) and prices of healthy staple foods ( β =–0·49, 95 % CI –0·90, –0·03) for the combined group v . control, but not for other intervention groups. There were no significant intervention effects on storeowner psychosocial factors. Conclusions All interventions led to increased stock of healthier foods. The combined intervention was effective in increasing sales of healthier snacks, even though discounts on snacks were not passed to the consumer. Experimental research in small stores is needed to understand the mechanisms by which store-directed price promotions can increase healthy food supply and demand

    Generative Pedagogies: Activating Learners through Student-centered Practices

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    This collective dissertation contains the efforts of a group of curious, committed, and creative educators on the hunt for high-impact instructional approaches that empower and emancipate learners. Although each study within the dissertation is anchored in its own setting--and those settings represent a diverse collection of learning sites--a single thread connects them all: Each study inquires into the impact of a generative pedagogy. By “generative,” we mean to highlight methods that focus on helping learners of all kinds develop creativity and take ownership over their learning, approaches that will help them build agency and grow skills simultaneously. Here, we explore the complex relationships between attitudes and outcomes in several different ways. These studies investigate the efficacy of workshop model instruction, divergent thinking protocols, and explicit growth mindset instruction for students with disabilities in English Language Arts (ELA) classrooms, the impact of choice- and studio-based approaches in Art classrooms, and the overall impact of growth mindset characteristics on teachers’ attitudes and career paths. Generally speaking, these variables were found to have a significant, positive impact on both attitudes and outcomes. Additionally, some of these methods emerged as equity-building practices, working well overall but even better for students in demographic groups that often lag behind. Taken together, these approaches represent a perspective that honors learners as co-constructors of their own knowledge and makes salient a set of skills and habits that can contribute powerfully toward each individual learner’s success

    Variability in Microbial Community Composition and Function Between Different Niches Within a Coral Reef

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    To explore how microbial community composition and function varies within a coral reef ecosystem, we performed metagenomic sequencing of seawater from four niches across Heron Island Reef, within the Great Barrier Reef. Metagenomes were sequenced from seawater samples associated with (1) the surface of the coral species Acropora palifera, (2) the surface of the coral species Acropora aspera, (3) the sandy substrate within the reef lagoon and (4) open water, outside of the reef crest. Microbial composition and metabolic function differed substantially between the four niches. The taxonomic profile showed a clear shift from an oligotroph-dominated community (e.g. SAR11, Prochlorococcus, Synechococcus) in the open water and sandy substrate niches, to a community characterised by an increased frequency of copiotrophic bacteria (e.g. Vibrio, Pseudoalteromonas, Alteromonas) in the coral seawater niches. The metabolic potential of the four microbial assemblages also displayed significant differences, with the open water and sandy substrate niches dominated by genes associated with core house-keeping processes such as amino acid, carbohydrate and protein metabolism as well as DNA and RNA synthesis and metabolism. In contrast, the coral surface seawater metagenomes had an enhanced frequency of genes associated with dynamic processes including motility and chemotaxis, regulation and cell signalling. These findings demonstrate that the composition and function of microbial communities are highly variable between niches within coral reef ecosystems and that coral reefs host heterogeneous microbial communities that are likely shaped by habitat structure, presence of animal hosts and local biogeochemical conditions.Human Frontier Science Program (Strasbourg, France) (Grant RGY0089/2011

    Heteroatom and side chain effects on the optical and photophysical properties: ultrafast and nonlinear spectroscopy of new Naphtho[1,2-b:5,6-b ']difuran donor polymers

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    The photophysical and electronic properties of four novel conjugated donor polymers were investigated to understand the influence of heteroatoms (based on the first two member chalcogens) in the polymer backbone. The side chains were varied as well to evaluate the effect of polymer solubility on the photophysical properties. The donor–acceptor polymer structure is based on naptho[1,2-b:5,6-b′]difuran as the donor moiety, and either 3,6-di(furan-2-yl)-1,4-diketopyrrolo[3,4-c]pyrrole or 3,6-di(thiophen-2-yl)-1,4-diketopyrrolo[3,4-c]pyrrole as the acceptor moiety. Steady-state absorption studies showed that the polymers with the furan moiety in the backbone displayed a favorable tendency of capturing more solar photons when used in a photovoltaic device. This is observed experimentally by the higher extinction coefficient in the visible and near-infrared regions of these polymers relative to that of their thiophene counterparts. The excitonic lifetimes were monitored using ultrafast dynamics, and the results obtained show that the type of heteroatom π-linker used in the backbone affects the decay dynamics. Furthermore, the side chain also plays a role in determining the fluorescence decay time. Quantum chemical simulations were performed to describe the absorption energies and transition characters. Two-photon absorption cross sections (TPA-δ) were analyzed with the simulations, illustrating the planarity of the backbone in relation to its torsional angles. Because of the planarity in the molecular backbone, the polymer with the furan π-linker showed a higher TPA-δ relative to that of its thiophene counterpart. This suggests that the furan compound will display higher charge transfer (CT) tendencies in comparison to those of their thiophene analogues. The pump–probe transient absorption technique was employed to probe the nonemissive states (including the CT state) of the polymers, and unique activities were captured at 500 and 750 nm for all of the studied compounds. Target and global analyses were performed to understand the dynamics of each peak and deduce the number of components responsible for the transient behavior observed respectively. The results obtained suggest that the furan π-linker component of a donor and acceptor moiety in a conjugated polymer might be a more suitable candidate compared with its more popular chalcogenic counterpart, thiophene, for use as donor materials in bulk heterojunction photovoltaic devices.Support for this investigation is provided by the National Science Foundation (DMR-1709005) Polymers (TGIII) and (DMR 1410088/1640297) Polymers (MJE). (DMR-1709005 - National Science Foundation; DMR 1410088/1640297 - National Science Foundation)Accepted manuscrip

    Evaluating the impact of fluorination on the electro-optical properties of cross-conjugated benzobisoxazoles

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    Published as part of The Journal of Physical Chemistry virtual special issue “William M. Jackson Festschrift”.Six 2,4,6,8-tetrarylbenzo[1,2-d:4,5-d′]bisoxazoles (BBOs) were synthesized: three bearing phenyl substituents at the 2- and 6-positions and three bearing perfluorophenyl groups at those positions. The influence of perfluoro-aryl group substitution on the physical, optical, and electronic properties of 2,4,6,8-tetrarylbenzo[1,2-d:4,5-d′]bisoxazoles (BBO) was evaluated using both experimental and theoretical methods. The density functional theory (DFT) model was found to be well-matched to the experimental optical data, as evidenced by the UV–vis spectra. Both cyclic voltammetry (CV) and ultraviolet photoelectron spectroscopy (UPS) were used to determine the position of the HOMO with varying results. The values obtained by CV were deeper than those obtained via UPS and correlated well with the theoretical calculations. However, the UPS values were more consistent with the expected outcomes for a system with segregated frontier molecular orbitals (FMOs). The UPS results are also supported by the electrostatic potential maps, which indicate that the electron density within the LUMO and HOMO is nearly completely localized along the 2,6- or 4,8-axis, respectively. The summation of the results indicates that strongly electron-withdrawing groups can be used to selectively tune the LUMO level with minor perturbation of the HOMO, something that is challenging to accomplish in typical donor–acceptor systems.We thank Dr. Norman Lee, Stephon Betts, and Dr. Paul Ralifo from the Chemical Instrumentation Facility at Boston University for compound analysis. We also thank Margaret Chern from the Dennis Lab at Boston University for assistance in obtaining fluorescence lifetimes and quantum yields. Next, we thank Volodimyr Duzhko at the Center for Electronic Materials and Devices at the University of Massachusetts-Amherst. We also thank the National Science Foundation (CHE-141373, CHE-1640298, and CHE-1413207) as well a supercomputer allocation by the Extreme Science and Engineering Discovery Environment (XSEDE) for the Comet supercomputer cluster provided by the San Diego Supercomputing Center (DMR-160146) for supporting this work. (CHE-141373 - National Science Foundation; CHE-1640298 - National Science Foundation; CHE-1413207 - National Science Foundation)Accepted manuscrip

    Custom fitted compression garments enhance recovery from muscle damage in rugby players

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    PURPOSE: To evaluate the effects of custom fitted compression garments (CG) on recovery from muscle damage in rugby players. METHODS: Forty-five players were tested for lower body strength, power, and indices of muscle-damage before completing a damaging protocol (20 x 20 m sprints with 5 m deceleration, 100 drop-jumps). Players were randomly assigned to wear either custom fitted (CF, n = 13), or standard sized CG (SSG, n = 16), or to received sham ultrasound therapy (CON, n = 16) immediately post-exercise. Players were re-tested immediately, then after 24 h and 48 h. RESULTS: Strength recovery was significantly different between groups (F = 2.7, p = 0.02), with only CF recovering to baseline values by 48 h (p = 0.973). Time x condition effects were also apparent for creatine kinase activity (χ = 30.4, p < 0.001) and mid-thigh girth (F = 3.7, p = 0.005), with faster recovery apparent in CF compared to both CON and SSG (p < 0.05). CONCLUSIONS: Custom fitted CG improved strength recovery and indices of muscle damage in rugby players, compared to controls and standard sized garments. PRACTICAL APPLICATIONS: Athletes and coaches would be advised to use appropriately fitted CG to enhance strength recovery following damaging exercise

    HAWAII ALGAL BIOFUEL

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    This report investigates the feasibility and affordability of producing algae-derived biofuel in Hawaii for military aviation. The authors evaluated methods for cultivation of algae, investigated the processes necessary to locally refine bio-oil into bio-kerosene, researched the environmental impacts of cultivation and refinement facilities in Hawaii, and studied the resultant cost per gallon of bio-kerosene production. Based on the current state of technology and the proposed system of systems architecture, this report estimates that bio-kerosene can be produced for $8.00 - 22.87/gal, indicating that although this system is technically feasible, it is unlikely to be affordable at current fuel prices without ongoing subsidy or further technical innovation.http://archive.org/details/hawaiialgalbiofu109453289

    State of the climate in 2018

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    In 2018, the dominant greenhouse gases released into Earth’s atmosphere—carbon dioxide, methane, and nitrous oxide—continued their increase. The annual global average carbon dioxide concentration at Earth’s surface was 407.4 ± 0.1 ppm, the highest in the modern instrumental record and in ice core records dating back 800 000 years. Combined, greenhouse gases and several halogenated gases contribute just over 3 W m−2 to radiative forcing and represent a nearly 43% increase since 1990. Carbon dioxide is responsible for about 65% of this radiative forcing. With a weak La Niña in early 2018 transitioning to a weak El Niño by the year’s end, the global surface (land and ocean) temperature was the fourth highest on record, with only 2015 through 2017 being warmer. Several European countries reported record high annual temperatures. There were also more high, and fewer low, temperature extremes than in nearly all of the 68-year extremes record. Madagascar recorded a record daily temperature of 40.5°C in Morondava in March, while South Korea set its record high of 41.0°C in August in Hongcheon. Nawabshah, Pakistan, recorded its highest temperature of 50.2°C, which may be a new daily world record for April. Globally, the annual lower troposphere temperature was third to seventh highest, depending on the dataset analyzed. The lower stratospheric temperature was approximately fifth lowest. The 2018 Arctic land surface temperature was 1.2°C above the 1981–2010 average, tying for third highest in the 118-year record, following 2016 and 2017. June’s Arctic snow cover extent was almost half of what it was 35 years ago. Across Greenland, however, regional summer temperatures were generally below or near average. Additionally, a satellite survey of 47 glaciers in Greenland indicated a net increase in area for the first time since records began in 1999. Increasing permafrost temperatures were reported at most observation sites in the Arctic, with the overall increase of 0.1°–0.2°C between 2017 and 2018 being comparable to the highest rate of warming ever observed in the region. On 17 March, Arctic sea ice extent marked the second smallest annual maximum in the 38-year record, larger than only 2017. The minimum extent in 2018 was reached on 19 September and again on 23 September, tying 2008 and 2010 for the sixth lowest extent on record. The 23 September date tied 1997 as the latest sea ice minimum date on record. First-year ice now dominates the ice cover, comprising 77% of the March 2018 ice pack compared to 55% during the 1980s. Because thinner, younger ice is more vulnerable to melting out in summer, this shift in sea ice age has contributed to the decreasing trend in minimum ice extent. Regionally, Bering Sea ice extent was at record lows for almost the entire 2017/18 ice season. For the Antarctic continent as a whole, 2018 was warmer than average. On the highest points of the Antarctic Plateau, the automatic weather station Relay (74°S) broke or tied six monthly temperature records throughout the year, with August breaking its record by nearly 8°C. However, cool conditions in the western Bellingshausen Sea and Amundsen Sea sector contributed to a low melt season overall for 2017/18. High SSTs contributed to low summer sea ice extent in the Ross and Weddell Seas in 2018, underpinning the second lowest Antarctic summer minimum sea ice extent on record. Despite conducive conditions for its formation, the ozone hole at its maximum extent in September was near the 2000–18 mean, likely due to an ongoing slow decline in stratospheric chlorine monoxide concentration. Across the oceans, globally averaged SST decreased slightly since the record El Niño year of 2016 but was still far above the climatological mean. On average, SST is increasing at a rate of 0.10° ± 0.01°C decade−1 since 1950. The warming appeared largest in the tropical Indian Ocean and smallest in the North Pacific. The deeper ocean continues to warm year after year. For the seventh consecutive year, global annual mean sea level became the highest in the 26-year record, rising to 81 mm above the 1993 average. As anticipated in a warming climate, the hydrological cycle over the ocean is accelerating: dry regions are becoming drier and wet regions rainier. Closer to the equator, 95 named tropical storms were observed during 2018, well above the 1981–2010 average of 82. Eleven tropical cyclones reached Saffir–Simpson scale Category 5 intensity. North Atlantic Major Hurricane Michael’s landfall intensity of 140 kt was the fourth strongest for any continental U.S. hurricane landfall in the 168-year record. Michael caused more than 30 fatalities and 25billion(U.S.dollars)indamages.InthewesternNorthPacific,SuperTyphoonMangkhutledto160fatalitiesand25 billion (U.S. dollars) in damages. In the western North Pacific, Super Typhoon Mangkhut led to 160 fatalities and 6 billion (U.S. dollars) in damages across the Philippines, Hong Kong, Macau, mainland China, Guam, and the Northern Mariana Islands. Tropical Storm Son-Tinh was responsible for 170 fatalities in Vietnam and Laos. Nearly all the islands of Micronesia experienced at least moderate impacts from various tropical cyclones. Across land, many areas around the globe received copious precipitation, notable at different time scales. Rodrigues and Réunion Island near southern Africa each reported their third wettest year on record. In Hawaii, 1262 mm precipitation at Waipā Gardens (Kauai) on 14–15 April set a new U.S. record for 24-h precipitation. In Brazil, the city of Belo Horizonte received nearly 75 mm of rain in just 20 minutes, nearly half its monthly average. Globally, fire activity during 2018 was the lowest since the start of the record in 1997, with a combined burned area of about 500 million hectares. This reinforced the long-term downward trend in fire emissions driven by changes in land use in frequently burning savannas. However, wildfires burned 3.5 million hectares across the United States, well above the 2000–10 average of 2.7 million hectares. Combined, U.S. wildfire damages for the 2017 and 2018 wildfire seasons exceeded $40 billion (U.S. dollars)

    Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.

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    Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
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