Persistence-driven durotaxis: Generic, directed motility in rigidity gradients

Cells move differently on substrates with different elasticities. In particular, the persistence time of their motion is higher on stiffer substrates. We show that this behavior will result in a net transport of cells directed up a soft-to-stiff gradient. Using simple random walk models with controlled persistence and stochastic simulations, we characterize this propensity to move in terms of the durotactic index measured in experiments. A one-dimensional model captures the essential features of this motion and highlights the competition between diffusive spreading and linear, wavelike propagation. Since the directed motion is rooted in a non-directional change in the behavior of individual cells, the motility is a kinesis rather than a taxis. Persistence-driven durokinesis is generic and may be of use in the design of instructive environments for cells and other motile, mechanosensitive objects.Comment: 5 pages, 4 figure

Matrix elasticity in vitro controls muscle stem cell fate in vivo

Almost every laboratory that grows mammalian cells today grows their cells on tissue culture plastic, which was introduced to cell culture decades ago based on properties such as inertness, transparency, and so forth. However, plastic is rigid and unlike the many soft tissues in the body. Polymer gel systems that mimic the softness of various tissues have been developed over the past decade to test and understand the effects of rigidity on cells such as muscle cells. One recent study even shows that muscle stem cells expand much better in vitro on muscle-mimetic gels and that such cells prove optimal for engraftment in muscle

The Vehicle, Spring 2000

Vol. 41, No. 2 Table of Contents UntitledMatthew A. Thomaspage 4 Fred\u27s PenAutumn Williamspage 5 tomatoesDave Moutraypage 6 AFRICABusinge Roger Godfreypage 7 seeking OutKim Hunterpage 8 Razorblade, Crystal I.Jason Brownpage 9 UntitledMegan Guernseypage 10 CoyoteAutumn Williamspage 11 BaptizedStephanie Carpenterpage 13 BrotherTara Coburnpage 14 My 1984Dave Moutraypage 15 what little boys and girls are made ofKristi Brownfieldpage 17 To GerriMegan Guernseypage 19 JunieJoe Raabpage 20 BeatWes Paytonpage 21 MercyAutumn Williamspage 23 TravelingDenise Fitzerpage 24 UntitledMatthew A. Thomaspage 25 a story of rapeAnnie Whitepage 26 Teddy RhexisPaul Austerpage 30https://thekeep.eiu.edu/vehicle/1074/thumbnail.jp

The Vehicle, Spring 2000

Vol. 41, No. 2 Table of Contents UntitledMatthew A. Thomaspage 4 Fred\u27s PenAutumn Williamspage 5 tomatoesDave Moutraypage 6 AFRICABusinge Roger Godfreypage 7 seeking OutKim Hunterpage 8 Razorblade, Crystal I.Jason Brownpage 9 UntitledMegan Guernseypage 10 CoyoteAutumn Williamspage 11 BaptizedStephanie Carpenterpage 13 BrotherTara Coburnpage 14 My 1984Dave Moutraypage 15 what little boys and girls are made ofKristi Brownfieldpage 17 To GerriMegan Guernseypage 19 JunieJoe Raabpage 20 BeatWes Paytonpage 21 MercyAutumn Williamspage 23 TravelingDenise Fitzerpage 24 UntitledMatthew A. Thomaspage 25 a story of rapeAnnie Whitepage 26 Teddy RhexisPaul Austerpage 30https://thekeep.eiu.edu/vehicle/1074/thumbnail.jp

Indications for thyroid FNA and pre-FNA requirements: A synopsis of the National Cancer Institute Thyroid Fine-Needle Aspiration State of the Science Conference

The National Cancer Institute (NCI) sponsored the NCI Thyroid Fine-Needle Aspiration (FNA) State of the Science Conference on October 22–23, 2007 in Bethesda, MD. The 2-day meeting was accompanied by a permanent informational website and several on-line discussions between May 1 and December 15, 2007 ( http://thyroidfna.cancer.gov ). This document summarizes the indications for performing an FNA of a nodule discovered by physical examination or an imaging study; the indications for using ultrasound versus palpation for guidance when performing a thyroid FNA; the issues surrounding informed consent for thyroid FNA; and the information required on a requisition form that accompanies a thyroid FNA specimen. ( http://thyroidfna.cancer.gov/pages/info/agenda/ ) Diagn. Cytopathol. 2008;36:390–399. © 2008 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58658/1/20827_ftp.pd

Duke Surgery Patient Safety: an open-source application for anonymous reporting of adverse and near-miss surgical events

BACKGROUND: Studies have shown that 4% of hospitalized patients suffer from an adverse event caused by the medical treatment administered. Some institutions have created systems to encourage medical workers to report these adverse events. However, these systems often prove to be inadequate and/or ineffective for reviewing the data collected and improving the outcomes in patient safety. OBJECTIVE: To describe the Web-application Duke Surgery Patient Safety, designed for the anonymous reporting of adverse and near-miss events as well as scheduled reporting to surgeons and hospital administration. SOFTWARE ARCHITECTURE: DSPS was developed primarily using Java language running on a Tomcat server and with MySQL database as its backend. RESULTS: Formal and field usability tests were used to aid in development of DSPS. Extensive experience with DSPS at our institution indicate that DSPS is easy to learn and use, has good speed, provides needed functionality, and is well received by both adverse-event reporters and administrators. DISCUSSION: This is the first description of an open-source application for reporting patient safety, which allows the distribution of the application to other institutions in addition for its ability to adapt to the needs of different departments. DSPS provides a mechanism for anonymous reporting of adverse events and helps to administer Patient Safety initiatives. CONCLUSION: The modifiable framework of DSPS allows adherence to evolving national data standards. The open-source design of DSPS permits surgical departments with existing reporting mechanisms to integrate them with DSPS. The DSPS application is distributed under the GNU General Public License

Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times $10^{-22}$.Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July 200

Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers

We study frequency dependent (FD) input-output schemes for signal-recycling interferometers, the baseline design of Advanced LIGO and the current configuration of GEO 600. Complementary to a recent proposal by Harms et al. to use FD input squeezing and ordinary homodyne detection, we explore a scheme which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are sub-optimal among all possible input-output schemes, provide a global noise suppression by the power squeeze factor, while being realizable by using detuned Fabry-Perot cavities as input/output filters. At high frequencies, the two schemes are shown to be equivalent, while at low frequencies our scheme gives better performance than that of Harms et al., and is nearly fully optimal. We then study the sensitivity improvement achievable by these schemes in Advanced LIGO era (with 30-m filter cavities and current estimates of filter-mirror losses and thermal noise), for neutron star binary inspirals, and for narrowband GW sources such as low-mass X-ray binaries and known radio pulsars. Optical losses are shown to be a major obstacle for the actual implementation of these techniques in Advanced LIGO. On time scales of third-generation interferometers, like EURO/LIGO-III (~2012), with kilometer-scale filter cavities, a signal-recycling interferometer with the FD readout scheme explored in this paper can have performances comparable to existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi

Search for gravitational wave bursts in LIGO's third science run

We report on a search for gravitational wave bursts in data from the three LIGO interferometric detectors during their third science run. The search targets subsecond bursts in the frequency range 100-1100 Hz for which no waveform model is assumed, and has a sensitivity in terms of the root-sum-square (rss) strain amplitude of hrss ~ 10^{-20} / sqrt(Hz). No gravitational wave signals were detected in the 8 days of analyzed data.Comment: 12 pages, 6 figures. Amaldi-6 conference proceedings to be published in Classical and Quantum Gravit

Quantum state preparation and macroscopic entanglement in gravitational-wave detectors

Long-baseline laser-interferometer gravitational-wave detectors are operating at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within a broad frequency band. Such a low classical noise budget has already allowed the creation of a controlled 2.7 kg macroscopic oscillator with an effective eigenfrequency of 150 Hz and an occupation number of 200. This result, along with the prospect for further improvements, heralds the new possibility of experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical behavior of objects in the realm of everyday experience - using gravitational-wave detectors. In this paper, we provide the mathematical foundation for the first step of a MQM experiment: the preparation of a macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum state, which is possible if the interferometer's classical noise beats the SQL in a broad frequency band. Our formalism, based on Wiener filtering, allows a straightforward conversion from the classical noise budget of a laser interferometer, in terms of noise spectra, into the strategy for quantum state preparation, and the quality of the prepared state. Using this formalism, we consider how Gaussian entanglement can be built among two macroscopic test masses, and the performance of the planned Advanced LIGO interferometers in quantum-state preparation