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Cognitive behavioral training reverses the effect of pain exposure on brain-network activity
Repeated sensory exposures shape the brain's function and its responses to environmental stimuli. An important clinical and scientific question is how exposure to pain affects brain network activity and whether that activity is modifiable with training. We sought to determine whether repeated pain exposure would impact brain-network activity and whether these effects can be reversed by cognitive behavioral training (CBT). Healthy subjects underwent 8 experimental sessions on separate days where they received painful thermal stimuli. They were randomly assigned to groups receiving either CBT (Regulate group, n=17) or a non-pain-focused treatment (Control group, n=13). Before and after these sessions, participants underwent functional MRI (fMRI) during painful stimulation and at rest. The effect of repeated pain over time in the Control group was a decrease in the neurotypical pain-evoked default mode network (DMN) deactivation. The Regulate group did not show these DMN effects but rather had decreased deactivation of the right ventrolateral prefrontal cortex (R vlPFC) of the executive control network. In the Regulate group, reduced pain-evoked DMN deactivation was associated with greater individual reduction in pain intensity and unpleasantness over time. Finally, the Regulate group showed enhanced resting functional connectivity between areas of the DMN and executive control network over time, compared to the Control group. Our study demonstrates that trainable cognitive states can alter the effect of repeated sensory exposure on the brain. The findings point to the potential utility of cognitive training to prevent changes in brain network connectivity that occur with repeated pain experience
The Evaluation and Followup of Children Referred to Pediatric Endocrinologists for Short Stature
Objective. To characterize the pediatric endocrinologists' evaluation and followup of short-statured patients.
Study Design. Observational study of 21,548 short-statured children (April 1996 to December 1999). Baseline demographics, laboratory testing, height standard deviation score (SDS), target height, and height relative to target height were analyzed at initial and return visits with the specialist. Patients were scheduled for at least one return visit and no recombinant human growth hormone therapy was administered. Results. Mean patient age was 8.6 years with a mean height SDS of −2.1. Patients were predominantly male (69%), prepubertal (73%), and white (76%). Few screening tests were obtained during initial evaluation. Nearly 40% of children did not return for their second scheduled visit. The follow-up rate was unrelated to demographics or degree of short stature. Conclusions. Low return rates limit specialists' ability to monitor growth or obtain laboratory testing over time. Further studies are needed to determine which tests should be obtained at the initial clinic visit as well as the basis for the low return rate in this group of children
Actin and dynamin2 dynamics and interplay during clathrin-mediated endocytosis.
Clathrin-mediated endocytosis (CME) involves the recruitment of numerous proteins to sites on the plasma membrane with prescribed timing to mediate specific stages of the process. However, how choreographed recruitment and function of specific proteins during CME is achieved remains unclear. Using genome editing to express fluorescent fusion proteins at native levels and live-cell imaging with single-molecule sensitivity, we explored dynamin2 stoichiometry, dynamics, and functional interdependency with actin. Our quantitative analyses revealed heterogeneity in the timing of the early phase of CME, with transient recruitment of 2-4 molecules of dynamin2. In contrast, considerable regularity characterized the final 20 s of CME, during which ∼26 molecules of dynamin2, sufficient to make one ring around the vesicle neck, were typically recruited. Actin assembly generally preceded dynamin2 recruitment during the late phases of CME, and promoted dynamin recruitment. Collectively, our results demonstrate precise temporal and quantitative regulation of the dynamin2 recruitment influenced by actin polymerization
International expert workshop on the analysis of the economic and public health impacts of air pollution: workshop summary.
Forty-nine experts from 18 industrial and developing countries met on 6 September 2001 in Garmisch-Partenkirchen, Germany, to discuss the economic and public health impacts of air pollution, particularly with respect to assessing the public health benefits from technologies and policies that reduce greenhouse gas (GHG) emissions. Such measures would provide immediate public health benefits, such as reduced premature mortality and chronic morbidity, through improved local air quality. These mitigation strategies also allow long-term goals--for example, reducing the buildup of GHG emissions--to be achieved alongside short-term aims, such as immediate improvements in air quality, and therefore benefits to public health. The workshop aimed to foster research partnerships by improving collaboration and communication among various agencies and researchers; providing a forum for presentations by sponsoring agencies and researchers regarding research efforts and agency activities; identifying key issues, knowledge gaps, methodological shortcomings, and research needs; and recommending activities and initiatives for research, collaboration, and communication. This workshop summary briefly describes presentations made by workshop participants and the conclusions of three separate working groups: economics, benefits transfer, and policy; indoor air quality issues and susceptible populations; and development and transfer of dose-response relationships and exposure models in developing countries. Several common themes emerged from the working group sessions and subsequent discussion. Key recommendations include the need for improved communication and extended collaboration, guidance and support for researchers, advances in methods, and resource support for data collection, assessment, and research
The Tsimane Health and Life History Project: Integrating Anthropology and Biomedicine
The Tsimane Health and Life History Project, an integrated bio-behavioral study of the human life course, is designed to test competing hypotheses of human life-history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a highfertility, kin-based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well-being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project’s goals, history, and main findings since its inception in 2002. We reflect on the implications of current findings and highlight the need for more coordinated ethnographic and biomedical study of contemporary nonindustrial populations to address broad questions that can situate evolutionary anthropology in a key position within the social and life sciences
Deep ACS Imaging in the Globular Cluster NGC6397: Dynamical Models
We present N-body models to complement deep imaging of the metal-poor
core-collapsed cluster NGC6397 obtained with the Hubble Space Telescope. All
simulations include stellar and binary evolution in-step with the stellar
dynamics and account for the tidal field of the Galaxy. We focus on the results
of a simulation that began with 100000 objects (stars and binaries), 5%
primordial binaries and Population II metallicity. After 16 Gyr of evolution
the model cluster has about 20% of the stars remaining and has reached
core-collapse. We compare the color-magnitude diagrams of the model at this age
for the central region and an outer region corresponding to the observed field
of NGC6397 (about 2-3 half-light radii from the cluster centre). This
demonstrates that the white dwarf population in the outer region has suffered
little modification from dynamical processes - contamination of the luminosity
function by binaries and white dwarfs with non-standard evolution histories is
minimal and should not significantly affect measurement of the cluster age. We
also show that the binary fraction of main-sequence stars observed in the
NGC6397 field can be taken as representative of the primordial binary fraction
of the cluster. For the mass function of the main-sequence stars we find that
although this has been altered significantly by dynamics over the cluster
lifetime, especially in the central and outer regions, that the position of the
observed field is close to optimal for recovering the initial mass function of
the cluster stars (below the current turn-off mass). More generally we look at
how the mass function changes with radius in a dynamically evolved stellar
cluster and suggest where the best radial position to observe the initial mass
function is for clusters of any age.Comment: 34 pages, 11 figures, submitted to AJ, companion paper to 0708.403
The Dynamical State and Mass-Concentration Relation of Galaxy Clusters
We use the Millennium Simulation series to study how the dynamical state of
dark matter halos affects the relation between mass and concentration. We find
that a large fraction of massive systems are identified when they are
substantially out of equilibrium and in a particular phase of their dynamical
evolution: the more massive the halo, the more likely it is found at a
transient stage of high concentration. This state reflects the recent assembly
of massive halos and corresponds to the first pericentric passage of
recently-accreted material when, before virialization, the kinetic and
potential energies reach maximum and minimum values, respectively. This result
explains the puzzling upturn in the mass-concentration relation reported in
recent work for massive halos; indeed, the upturn disappears when only
dynamically-relaxed systems are considered in the analysis. Our results warn
against applying simple equilibrium models to describe the structure of rare,
massive galaxy clusters and urges caution when extrapolating scaling laws
calibrated on lower-mass systems, where such deviations from equilibrium are
less common. The evolving dynamical state of galaxy clusters ought to be
carefully taken into account if cluster studies are to provide precise
cosmological constraints.Comment: 8 Pages. Minor changes to match published versio
PET and SPECT Imaging of the Brain: History, Technical Considerations, Applications, and Radiotracers
Advances in nuclear medicine have revolutionized our ability to accurately diagnose patients with a wide array of neurologic pathologies and provide appropriate therapy. The development of new radiopharmaceuticals has made possible the identification of regional differences in brain tissue composition and metabolism. In addition, the evolution of 3-dimensional molecular imaging followed by fusion with computed tomography and magnetic resonance imaging have allowed for more precise localization of pathologies. This review will introduce single photon emission computed tomography and positron emission tomographic imaging of the brain, including the history of their development, technical considerations, and a brief overview of pertinent radiopharmaceuticals and their applications
Grid-Enabling a Vibroacoustic Analysis Application
This paper describes the process of grid-enabling a vibroacoustic analysis application using the Globus Toolkit 3.2.1. This is the first step in a project intended to grid-enable a suite of tools being developed as a service-oriented architecture for spacecraft telemetry analysis. Many of the applications in the suite are compute intensive and would benefit from significantly improved performance. In this paper we show the advantage of using Globus to grid-enable a single tool in a vibroacoustic analysis flow, with the result that using as few as eleven nodes, that tool’s runtime improved by a factor of eight. While communication overhead does affect performance, these results also indicate that coordinated communication and execution scheduling as part of workflow management would be able to significantly improve overall efficiency. In the larger context, our experience also shows that the service-oriented architecture approach, using grid computing tools, can provide a more flexible system design, in addition to improved performance and increased utilization of resources. We also provide some lessons learned in using the Globus Toolkit
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