18,667 research outputs found
Consumption of Organic Foods from a Life History Perspective: An Exploratory Study among Danish Consumers
No summary availabl
Halflife of 56Ni in cosmic rays
A measurement of the 56Ni cosmic ray abundance has been discussed as a
possible tool to determine the acceleration time scale of relativistic
particles in cosmic rays. This conjecture will depend on the halflife of
totally ionized 56Ni which can only decay by higher-order forbidden
transitions. We have calculated this halflife within large-scale shell model
calculations and find t_{1/2} \approx 4 \times 10^4 years, only slightly larger
than the currently available experimental lower limit, but too short for 56Ni
to serve as a cosmic ray chronometer.Comment: 3 pages, 1 figur
Review of literature relating to the modeling of soil temperatures based on meteorological factors
Abstracts of 72 papers, journal articles, and other publications are presented. The applicabilities of each is assessed for use in improving winterkill parameters for a winter wheat model
The admission of religious nonconformists to the universities of Oxford and Cambridge and to degrees in those universities, 1828--1871
Drivers and Driver Assistance Systems: How Well do They Match?
New technology is appearing in vehicles that increasingly allows them to “know” where they are, their relationships to other vehicles on the road, and whether a crash is imminent. At the same time, and more quickly, drivers are becoming more connected to the world outside their cars through similar advances in electronic technology. The first trend promises to help drivers prevent crashes while the second raises fears of increasingly chaotic driving as drivers’ minds are elsewhere than on the driving task. Whether the promise of crash avoidance or the fear of driving chaos is realized depends on how drivers actually drive and whether the assumptions made about how they drive are correct. In fact, the US has not seen increases in crash risk as drivers’ use of electronics has increased nor are all crash avoidance systems having the expected benefits. In addition to exploring these data, the presentation will address some of the assumptions made about driving (e.g., that driving is difficult, that it requires fully conscious attention, that drivers will respond to information about their vehicles, and others) and whether those assumptions appear to fit the data on crash avoidance and distracted driving. It also will discuss “old” technology (e.g., roundabout intersections and automated enforcement) that may complement vehicle electronics in bringing drivers’ wandering attentions back to the road
Host-microbe interactions in non-native estuarine anemones: biogeography and temperature
Non-native species are increasing in prevalence around the world, resulting in negative economic and ecological impacts. However, the broad distributions of non-native species also offer a system for investigating the response of host-associated microbial communities to environmental factors across a range of ecological scales. At the broadest scale, I investigated the geography of microbial communities in the non-native estuarine anemone Diadumene lineata on the west coast of the United States of America. Across latitudes, microbial community composition was very similar and displayed a high percentage of Klebsiella spp. at all sites. However, the communities in California tended to exhibit higher richness, Shannon-Wiener diversity, and beta-dispersion than the communities in Oregon and Washington, driven by an abundance of Desulfobacterota. In a stress experiment, where three anemone species (Diadumene lineata, Diadumene leucolena, and Metridium senile) were subjected to a gradient from 0-40°C to evaluate each species’ capacity for buffering their microbial community against thermal stress, I found species-specific patterns across temperatures, with only M. senile exhibiting evidence of buffering at moderate temperatures. In contrast, D. lineata and D. leucolena did not appear to be buffering their microbial communities, with D. lineata displaying unique community compositions across temperatures, while the communities on D. leucolena generally exhibited high beta-dispersion. Finally, I isolated anemone-associated bacteria on a novel medium made of anemone tissue and measured their growth from 30-40°C, identifying candidates for beneficial host-microbe interactions in warm environments. The anemone-based medium overwhelmingly selected for the genera Pseudoalteromonas and Peribacillis, regardless of anemone host species. Peribacillus spp. were particularly thermal tolerant, growing similarly from 30-40°C, while Pseudoalteromonas spp. grew well from 30-35°C. The remaining tested genera preferred 30°C, however one of the Litoreibacter sp. produced a putative melanin that may protect cells against thermal stress. This is the first study exploring microbial communities in the non-native estuarine anemone D. lineata and lays the foundation for an expanded global assessment of latitudinal gradients, investigating how additional abiotic factors like genotype and pH drive microbial community composition, and directly testing beneficial host-microbe interactions with isolated bacteria
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