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Collaborative Computation in Self-Organizing Particle Systems
Many forms of programmable matter have been proposed for various tasks. We
use an abstract model of self-organizing particle systems for programmable
matter which could be used for a variety of applications, including smart paint
and coating materials for engineering or programmable cells for medical uses.
Previous research using this model has focused on shape formation and other
spatial configuration problems (e.g., coating and compression). In this work we
study foundational computational tasks that exceed the capabilities of the
individual constant size memory of a particle, such as implementing a counter
and matrix-vector multiplication. These tasks represent new ways to use these
self-organizing systems, which, in conjunction with previous shape and
configuration work, make the systems useful for a wider variety of tasks. They
can also leverage the distributed and dynamic nature of the self-organizing
system to be more efficient and adaptable than on traditional linear computing
hardware. Finally, we demonstrate applications of similar types of computations
with self-organizing systems to image processing, with implementations of image
color transformation and edge detection algorithms
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Addition of Inflammatory Biomarkers Did Not Improve Diabetes Prediction in the Community: The Framingham Heart Study
Background: Prior studies have reported conflicting findings with regard to the association of biomarkers in the prediction of incident type 2 diabetes. We evaluated 12 biomarkers as possible diabetes predictors in the Framingham Heart Study. Methods and results: Biomarkers representing inflammation (C-reactive protein, interleukin-6, monocyte chemoattractant protein-1, tumor necrosis factor receptor 2, osteoprotegerin, and fibrinogen), endothelial dysfunction (intercellular adhesion molecule-1), vascular damage (CD40-ligand, P-selectin, and lipoprotein-associated phospholipase A2 mass and activity), and oxidative stress (urinary isoprostanes) were measured in participants without diabetes attending the Offspring seventh (n=2499) or multiethnic Omni second (n=189) examination (1998â2001). Biomarkers were loge transformed and standardized. Multivariable logistic regression tested each biomarker in association with incident diabetes at a follow-up examination (the Offspring eighth and Omni third examination; mean 6.6 years later), with adjustment for age, sex, cohort, body mass index, fasting glucose, systolic blood pressure, high-density lipoprotein cholesterol, triglycerides, and smoking. C statistics were evaluated with and without inflammatory markers. In 2638 participants (56% women, mean age 59 years), 162 (6.1%) developed type 2 diabetes. All biomarkers, excluding osteoprotegerin, were associated with the outcome with adjustment for age, sex, and cohort; however, none remained significant after multivariable adjustment (all P>0.05). The c statistic from the model including only clinical covariates (0.89) did not statistically significantly improve after addition of biomarkers (all P>0.10). Conclusions: Biomarkers representing different inflammatory pathways are associated with incident diabetes but do not remain statistically significant after adjustment for established clinical covariates. Inflammatory biomarkers might not be an effective resource to predict type 2 diabetes in community-based samples
Preface
The University of Pennsylvania Working Papers in Linguistics (PWPL) is an occasional series published by the Penn Linguistics Club, the graduate student organization of the Linguistics Department of the University of Pennsylvania. The series has included volumes of previously unpublished work, or work in progress, by linguists with an ongoing affiliation with the Department, as well as volumes of papers from the NWAVE conference and the Penn Linguistics Colloquium.
The current PWPL series editors are Jim Alexander, Alexis Dimitriadis, Na-ÂâRae Han, Elsi Kaiser, Michelle Minnick Fox, Christine Moisset, and Alexander Williams
Preface
The University of Pennsylvania Working Papers in Linguistics (PWPL) is an occasional series published by the Penn Linguistics Club, the graduate student organization of the Linguistics Department of the University of Pennsylvania. The series has included volumes of previously unpublished work, or work in progress, by linguists with an ongoing affiliation with the Department, as well as volumes of papers from the NWAVE conference and the Penn Linguistics Colloquium.
The current PWPL series editors are Jim Alexander, Alexis Dimitriadis, Na-ÂâRae Han, Elsi Kaiser, Michelle Minnick Fox, Christine Moisset, and Alexander Williams
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Pericardial Fat is Associated With Atrial Conduction: The Framingham Heart Study
Background: Obesity is associated with altered atrial electrophysiology and a prominent risk factor for atrial fibrillation. Body mass index, the most widely used adiposity measure, has been related to atrial electrical remodeling. We tested the hypothesis that pericardial fat is independently associated with electrocardiographic measures of atrial conduction. Methods and Results: We performed a crossâsectional analysis of 1946 Framingham Heart Study participants (45% women) to determine the relation between pericardial fat and atrial conduction as measured by P wave indices (PWI): PR interval, P wave duration (Pâduration), P wave amplitude (Pâamplitude), P wave area (Pâarea), and P wave terminal force (Pâterminal). We performed sexâstratified linear regression analyses adjusted for relevant clinical variables and ectopic fat depots. Each 1âSD increase in pericardial fat was significantly associated with PR interval (β=1.7 ms, P=0.049), Pâduration (β=2.3 ms, P<0.001), and Pâterminal (β=297 ÎźV¡ms, P<0.001) among women; and Pâduration (β=1.2 ms, P=0.002), Pâamplitude (β=â2.5 ÎźV, P<0. 001), and Pâterminal (β=160 ÎźV¡ms, P=0.002) among men. Among both sexes, pericardial fat was significantly associated with Pâduration in analyses additionally adjusting for visceral fat or intrathoracic fat; a similar but nonâsignificant trend existed with Pâterminal. Among women, pericardial fat was significantly associated with P wave area after adjustment for visceral and intrathoracic fat. Conclusions: Pericardial fat is associated with atrial conduction as quantified by PWI, even with adjustment for extracardiac fat depots. Further studies are warranted to identify the mechanisms through which pericardial fat may modify atrial electrophysiology and promote subsequent risk for arrhythmogenesis
Distinct EEG amplitude suppression to facial gestures as evidence for a mirror mechanism in newborn monkeys
At birth, human infants and newborns of other primate species demonstrate the capacity to attend and to respond to facial stimuli provided by a caregiver. Newborn infants are also capable of exhibiting a range of facial expressions. Identification of the neural underpinnings of these capacities represents a formidable challenge in understanding social development. One possible neuronal substrate is the mirror-neuron system assumed to activate shared motor cortical representations for both observation and production of actions. We tested this hypothesis by recording scalp electroencephalogram (EEG) from 1â7 days old newborn rhesus macaques who were observing and producing facial gestures. We found that 5â6 Hz EEG activity was suppressed both when the infants produced facial gestures and while they were observing facial gestures of a human experimenter, but not when they were observing non-biological stimuli. These findings demonstrate the presence of neural reactivity for biological, communicatively-relevant stimuli which may be a likely signature of neuronal mirroring. The basic elements of the mirror-neuron system appear to operate from the very first days of life and contribute to the encoding of socially relevant stimuli
Early social experience affects neural activity to affiliative facial gestures in newborn nonhuman primates
A fundamental issue in cognitive neuroscience is how the brain encodes the actions and intentions of others. The discovery of an action-production-perception mechanism underpinning such a capacity advanced our knowledge of how these processes occur; however, no study has examined how the early postnatal environment may shape action-production-perception. Here, we examined the effects of social experience on action-production-perception in 3-day-old rhesus macaques that were raised either with or without their biological mothers. We measured the neonatal imitation skills and brain electrical activity responses, while infants produced and observed facial gestures. We hypothesized that early social experiences may shape brain activity, as assessed via electroencephalogram suppression in the Îą band (5-7 Hz in infants, known as the mu rhythm) during action observation, and lead to more proficient imitation skills. Consistent with this hypothesis, the infants reared by their mothers were more likely to imitate lipsmacking (LS) - a natural, affiliative gesture - and exhibited greater mu rhythm desynchronization while viewing LS gestures than the nursery-reared infants. These effects were not found in response to tongue protrusion, a meaningless gesture, or a nonsocial control. These data suggest that socially enriched early experiences in the first days after birth increase brain sensitivity to socially relevant actions
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