Validation of Clinical Dynamic Contrast-Enhanced Magnetic Resonance Imaging Perfusion Modeling and Neoadjuvant Chemotherapy Response Prediction in Breast Cancer Using FDG and Cu-DOTA-Trastuzumab Positron Emission Tomography Studies.

Purpose: Perfusion modeling presents significant opportunities for imaging biomarker development in breast cancer but has historically been held back by the need for data beyond the clinical standard of care (SoC) and uncertainty in the interpretability of results. We aimed to design a perfusion model applicable to breast cancer SoC dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) series with results stable to low temporal resolution imaging, comparable with published results using full-resolution DCE-MRI, and correlative with orthogonal imaging modalities indicative of biophysical markers.

Methods: Subsampled high-temporal-resolution DCE-MRI series were run through our perfusion model and resulting fits were compared for consistency.

Neural correlates of semantic number: A cross-linguistic investigation.

One aspect of natural language comprehension is understanding how many of what or whom a speaker is referring to. While previous work has documented the neural correlates of number comprehension and quantity comparison, this study investigates semantic number from a cross-linguistic perspective with the goal of identifying cortical regions involved in distinguishing plural from singular nouns. Three fMRI datasets are used in which Chinese, French, and English native speakers listen to an audiobook of a children's story in their native language.

Stochastic modeling of influenza spread dynamics with recurrences.

We present results of a study of a simple, stochastic, agent-based model of influenza A infection, simulating its dynamics over the course of one flu season. Building on an early work of Bartlett, we define a model with a limited number of parameters and rates that have clear epidemiological interpretation and can be constrained by data. We demonstrate the occurrence of recurrent behavior in the infected number [more than one peak in a season], which is observed in data, in our simulations for populations consisting of cohorts with strong intra- and weak inter-cohort transmissibility.

The evolving Japanese: the dual structure hypothesis at 30.

The population history of Japan has been one of the most intensively studied anthropological questions anywhere in the world, with a huge literature dating back to the nineteenth century and before. A growing consensus over the 1980s that the modern Japanese comprise an admixture of a Neolithic population with Bronze Age migrants from the Korean peninsula was crystallised in Kazurō Hanihara's influential 'dual structure hypothesis' published in 1991. Here, we use recent research in biological anthropology, historical linguistics and archaeology to evaluate this hypothesis after three decades.

Spatio-temporal dynamics of Host-Virus competition: A model study of influenza A.

We present results of a study of the early-time response of the innate immune system to influenza virus infection in an agent-based model (ABM) of epithelial cell layers. We find that the competition between the anti-viral immune response and viral antagonism can lead to viral titers non-monotonic in the initial infection fraction as found in experiments. Our model includes a coarse-grained version of intra-cellular processes and inter-cellular communication via cytokine and virion diffusion.

Impact of after-hours telemedicine on hospitalizations in a skilled nursing facility.

Skilled nursing facilities (SNFs) are increasingly being called upon to prevent avoidable hospitalizations. Primary care provider (PCP) bedside assessment for change of condition in SNF patients is believed to improve care and reduce unnecessary hospitalizations, but PCPs are not always available on site in an SNF. This study addresses the potential clinical and financial impacts of an after-hours physician coverage service enabled by technology, TripleCare (TC), to prevent avoidable hospitalizations.

The ultrasound brain helmet: feasibility study of multiple simultaneous 3D scans of cerebral vasculature.

We describe early stage experiments to test the feasibility of an ultrasound brain helmet to produce multiple simultaneous real-time three-dimensional (3D) scans of the cerebral vasculature from temporal and suboccipital acoustic windows of the skull. The transducer hardware and software of the Volumetrics Medical Imaging (Durham, NC, USA) real-time 3D scanner were modified to support dual 2.5 MHz matrix arrays of 256 transmit elements and 128 receive elements which produce two simultaneous 64 degrees pyramidal scans.

Autonomous surgical robotics using 3-D ultrasound guidance: feasibility study.

The goal of this study was to test the feasibility of using a real-time 3D (RT3D) ultrasound scanner with a transthoracic matrix array transducer probe to guide an autonomous surgical robot. Employing a fiducial alignment mark on the transducer to orient the robot's frame of reference and using simple thresholding algorithms to segment the 3D images, we tested the accuracy of using the scanner to automatically direct a robot arm that touched two needle tips together within a water tank. RMS measurement error was 3.

Improving catalytic function by ProSAR-driven enzyme evolution.

We describe a directed evolution approach that should find broad application in generating enzymes that meet predefined process-design criteria. It augments recombination-based directed evolution by incorporating a strategy for statistical analysis of protein sequence activity relationships (ProSAR). This combination facilitates mutation-oriented enzyme optimization by permitting the capture of additional information contained in the sequence-activity data.