2,622 research outputs found
Interactions with combined chemical cues inform harvester ant foragers' decisions to leave the nest in search of food.
Social insect colonies operate without central control or any global assessment of what needs to be done by workers. Colony organization arises from the responses of individuals to local cues. Red harvester ants (Pogonomyrmex barbatus) regulate foraging using interactions between returning and outgoing foragers. The rate at which foragers return with seeds, a measure of food availability, sets the rate at which outgoing foragers leave the nest on foraging trips. We used mimics to test whether outgoing foragers inside the nest respond to the odor of food, oleic acid, the odor of the forager itself, cuticular hydrocarbons, or a combination of both with increased foraging activity. We compared foraging activity, the rate at which foragers passed a line on a trail, before and after the addition of mimics. The combination of both odors, those of food and of foragers, is required to stimulate foraging. The addition of blank mimics, mimics coated with food odor alone, or mimics coated with forager odor alone did not increase foraging activity. We compared the rates at which foragers inside the nest interacted with other ants, blank mimics, and mimics coated with a combination of food and forager odor. Foragers inside the nest interacted more with mimics coated with combined forager/seed odors than with blank mimics, and these interactions had the same effect as those with other foragers. Outgoing foragers inside the nest entrance are stimulated to leave the nest in search of food by interacting with foragers returning with seeds. By using the combined odors of forager cuticular hydrocarbons and of seeds, the colony captures precise information, on the timescale of seconds, about the current availability of food
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Sipping Fuel and Saving Lives: Increasing Fuel Economy without Sacrificing Safety
Demonstrates how new fuel-efficiency technologies make it possible, and advisable, to significantly increase the fuel economy of motor vehicles without compromising their safety
The hippocampus reevaluated in unconscious learning and memory: at a tipping point?
Classic findings from the neuropsychological literature invariably indicated that performances on tests of memory that can be accomplished without conscious awareness were largely spared in amnesia, while those that required conscious retrieval (e.g., via recognition or recall) of information learned in the very same sessions was devastatingly impaired. Based on reports of such dissociations, it was proposed that one of the fundamental distinctions between memory systems is whether or not they support conscious access to remembered content. Only recently have we come to realize that the putative systemic division of labor between conscious and unconscious memory is not so clean. A primary goal of this review is to examine recent evidence that has been advanced against the view that the hippocampus is selectively critical for conscious memory. Along the way, consideration is given to criticisms that have been levied against these findings, potential explanations for differences in the reported results are proposed, and methodological pitfalls in investigations of unconscious memory are discussed. Ultimately, it is concluded that a tipping point has been reached, and that while conscious recollection depends critically on hippocampal integrity, the reach of the hippocampus extends to unconscious aspects of memory performance when relational memory processing and representation are required
Lisa Madigan Follow Up From Thomas Greene
This exchange of letters also includes supporting exhibits to the Att. General\u27s testimonal responses
Algal food and fuel coproduction can mitigate greenhouse gas emissions while improving land and water-use efficiency
The goals of ensuring energy, water, food, and climate security can often conflict.Microalgae (algae) are
being pursued as a feedstockfor both food and fuels—primarily due to algae’s high areal yield and ability
to grow on non-arable land, thus avoiding common bioenergy-food tradeoffs. However, algal cultivation
requires significant energy inputs that may limit potential emission reductions.We examine the tradeoffs
associated with producing fuel andfood from algae at the energy–food–water–climate nexus.We use the
GCAM integrated assessment model to demonstrate that algalfood production can promote reductions
in land-use change emissions through the offset of conventional agriculture. However,fuel production,
either via co-production of algal food and fuel or complete biomass conversion to fuel, is necessary to
ensure long-term emission reductions, due to the high energy costs of cultivation. Cultivation of salt–
water algae for food products may lead to substantial freshwater savings; but, nutrients for algae
cultivation will need to be sourced from waste streams to ensure sustainability. By reducing the land
demand of food production, while simultaneously enhancingfood and energy security, algae can further
enable the development of terrestrial bioenergy technologies including those utilizing carbon capture and
storage. Our results demonstrate that large-scale algae research and commercialization efforts should
focus on developing both food and energy products to achieve environmental goals.https://iopscience.iop.org/article/10.1088/1748-9326/11/11/114006/metaPublished versio
An alternative to the alternatives: considering a progressive possibility for alternative schools
This dissertation is an exploration of alternative schools that are offered to students who might otherwise be kicked out or drop out of public schools. I examine the more traditional options offered by public school systems, as well as more unusual schools that offer a democratic education. My primary research question is: How can a high school create an engaging education around the values of peace and justice? After a discussion of my methods and how they have changed over the course of this project, I look at the history of democratic and progressive schooling, and compare and contrast that history with contemporary practices in public school. Then I look at the philosophy underlying school practices and policy. I examine how neoliberalist policies impact schools today, and then envision the philosophy of an alternative school that better serve students who do not experience success in more traditional public schools. From there I explore current practices, both in traditional schools and in schools that aim to provide a democratic education for students. I look at the benefits of providing an authentic, democratic, multicultural education that incorporates social justice and what I term spirit-learning, which aims to offer tools to students so that they learn how to create peace in their own, personal lives as they learn to work towards creating peace in their communities and in the world they will inherit
Comparison of diet quality, physical activity and biochemical values of older adults either reporting or not reporting use of lipid-lowering medication
Objectives: The aim of this study was to compare standard lipid profile, reported dietary intake, and physical activity in older adults who reported taking or not taking a lipid-lowering medication, namely statins.
Design: Cross-sectional study utilizing baseline data collected from a subsample of a larger randomized clinical trial, The Study of Exercise and Nutrition in Older Rhode Islanders (SENIOR) Project.
Participants and Setting: A total of 115 participants, 33 males and 82 females, over the age of 60, community-dwelling, primarily retired, and from East Providence, Rhode Island and surrounding communities in Rhode Island and Massachusetts.
Measurements: Height and weight were measured and used to calculate body mass index. Waist circumference was measured. Medical history and medication use surveys were completed. Dietary assessment was done via three 24 hour recalls using NDS-R. The Yale Physical Activity Survey was used to determine energy expenditure during exercise and a physical activity summary score. Fasting blood samples were obtained to determine lipid profile.
Results: 37 participants (32.2%) reported taking lipid-lowering medication, statins exclusively, and 78 (67.8%) reported not taking any lipid-lowering medication. Participants who reported taking statins had better lipid profiles than those participants who reported not taking statins but had significantly lower intakes of vitamin B12, vitamin K, calcium, and potassium. There were no differences between groups on reported physical activity. However, the mean intakes for both groups did not meet the Dietary Reference Intakes for multiple nutrients.
Conclusion: Older adults need additional education on the importance of lifestyle changes in reducing CHD risk, whether taking lipid-lowering medications or not
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