4,350 research outputs found
The Ecology and Evolution of Patience in Two New World Monkeys
Decision making often involves choosing between small, short-term rewards and large, long-term rewards. All animals, humans included, discount future rewards-the present value of delayed rewards is viewed as less than the value of immediate rewards. Despite its ubiquity, there exists considerable but unexplained variation between species in their capacity to wait for rewards-that is, to exert patience or self-control. Using two closely related primates-common marmosets (Callithrix jacchus) and cotton-top tamarins (Saguinus oedipus)-we uncover a variable that may explain differences in how species discount future rewards. Both species faced a self-control paradigm in which individuals chose between taking an immediate small reward and waiting a variable amount of time for a large reward. Under these conditions, marmosets waited significantly longer for food than tamarins. This difference cannot be explained by life history, social behaviour or brain size. It can, however, be explained by feeding ecology: marmosets rely on gum, a food product acquired by waiting for exudate to flow from trees, whereas tamarins feed on insects, a food product requiring impulsive action. Foraging ecology, therefore, may provide a selective pressure for the evolution of self-control.Psycholog
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Visual Representation in the Wild: How Rhesus Monkeys Parse Objects
Visual object representation was studied in free-ranging rhesus monkeys. To facilitate comparison with humans, and to provide a new tool for neurophysiologists, we used a looking time procedure originally developed for studies of human infants. Monkeys' looking times were measured to displays with one or two distinct objects, separated or together, stationary or moving. Results indicate that rhesus monkeys used featural information to parse the displays into distinct objects, and they found events in which distinct objects moved together more novel or unnatural than events in which distinct objects moved separately. These findings show both common-alities and contrasts with those obtained from human infants. We discuss their implications for the development and neural mechanisms of higher-level vision.Psycholog
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An electronic family health history tool to identify and manage patients at increased risk for colorectal cancer: protocol for a randomized controlled trial.
BackgroundColorectal cancer is the fourth most commonly diagnosed cancer in the United States. Approximately 3-10% of the population has an increased risk for colorectal cancer due to family history and warrants more frequent or intensive screening. Yet, < 50% of that high-risk population receives guideline-concordant care. Systematic collection of family health history and decision support may improve guideline-concordant screening for patients at increased risk of colorectal cancer. We seek to test the effectiveness of a web-based, systematic family health history collection tool and decision support platform (MeTree) to improve risk assessment and appropriate management of colorectal cancer risk among patients in the Department of Veterans Affairs primary care practices.MethodsIn this ongoing randomized controlled trial, primary care providers at the Durham Veterans Affairs Health Care System and the Madison VA Medical Center are randomized to immediate intervention or wait-list control. Veterans are eligible if assigned to enrolled providers, have an upcoming primary care appointment, and have no conditions that would place them at increased risk for colorectal cancer (such as personal history, adenomatous polyps, or inflammatory bowel disease). Those with a recent lower endoscopy (e.g. colonoscopy, sigmoidoscopy) are excluded. Immediate intervention patients put their family health history information into a web-based platform, MeTree, which provides both patient- and provider-facing decision support reports. Wait-list control patients access MeTree 12 months post-consent. The primary outcome is the risk-concordant colorectal cancer screening referral rate obtained via chart review. Secondary outcomes include patient completion of risk management recommendations (e.g. colonoscopy) and referral for genetic consultation. We will also conduct an economic analysis and an assessment of providers' experience with MeTree clinical decision support recommendations to inform future implementation efforts if the intervention is found to be effective.DiscussionThis trial will assess the feasibility and effectiveness of patient-collected family health history linked to decision support to promote risk-appropriate screening in a large healthcare system such as the Department of Veterans Affairs.Trial registrationClinicalTrials.gov, NCT02247336 . Registered on 25 September 2014
Global Climate Change, Food Security and the U.S. Food System
Climate change influences on the major pillars of food security. Each of the four elements of food security (availability,access,utilization,andstability) is vulnerable to changes in climate. For example,reductions in production related to regional drought influence food availability at multiple scales. Changes in price influences the ability of certain populations to purchase food (access). Utilization maybe affected when production zones shift, reducing the availability of preferred or culturally appropriate types of food within a region. Stability of the food supply may be highly uncertain given an increased incidence of extreme climatic events and their influence on production patterns
A Novel Approach to Constrain the Escape Fraction and Dust Content at High Redshift Using the Cosmic Infrared Background Fractional Anisotropy
The Cosmic Infrared Background (CIB) provides an opportunity to constrain
many properties of the high redshift (z>6) stellar population as a whole. This
background, specifically, from 1 to 200 microns, will contain any information
about the era of reionization and the stars responsible for producing these
ionizing photons. In this paper, we look at the fractional anisotropy delta I/I
of this high redshift population, which is the ratio of the magnitude of the
fluctuations (delta I) and the mean intensity (I). We show that this can be
used to constrain the escape fraction of the population as a whole. The
magnitude of the fluctuations of the CIB depend on the escape fraction, while
the mean intensity does not. This results in lower values of the escape
fraction producing higher values of the fractional anisotropy. This difference
is predicted to be larger at the longer wavelengths bands (above 10 microns),
albeit it is also much harder to observe in that range. We show that the
fractional anisotropy can also be used to separate a dusty from a dust-free
population. Finally, we discuss the constraints provided by current
observations on the CIB fractional anisotropy.Comment: 8 pages, 4 figures, accepted to ApJ, some clarifications added,
matches accepted versio
The Child Guidance Center
The child guidance center is the most recent manifestation of the interest in child welfare that has distinguished social thought in recent years. The close relationship of behavior and personality maladjustments to delinquency, crime, and insanity has made the guidance clinic a valuable agency for general social welfare.
It is the purpose of this study to indicate to some degree the need for scientific child guidance, to show how child guidance centers have developed, how they are operating, and what they are trying to accomplish. This account is primarily descriptive of the typical workings of the more important clinics in the field, because these serve as models for most of the smaller centers.
Sources of material have been for the most part the re ports and descriptions of those who are actively engaged in child guidance work. Additional information was obtained by investigation of available Milwaukee resources in child guidance
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