343 research outputs found
The causal effect of a timeout at stopping an opposing run in the NBA
In the summer of 2017, the National Basketball Association reduced the number
of total timeouts, along with other rule changes, to regulate the flow of the
game. With these rule changes, it becomes increasingly important for coaches to
effectively manage their timeouts. Understanding the utility of a timeout under
various game scenarios, e.g., during an opposing team's run, is of the utmost
importance. There are two schools of thought when the opposition is on a run:
(1) call a timeout and allow your team to rest and regroup, or (2) save a
timeout and hope your team can make corrections during play. This paper
investigates the credence of these tenets using the Rubin causal model
framework to quantify the causal effect of a timeout in the presence of an
opposing team's run. Too often overlooked, we carefully consider the stable
unit-treatment-value assumption (SUTVA) in this context and use SUTVA to
motivate our definition of units. To measure the effect of a timeout, we
introduce a novel, interpretable outcome based on the score difference to
describe broad changes in the scoring dynamics. This outcome is well-suited for
situations where the quantity of interest fluctuates frequently, a commonality
in many sports analytics applications. We conclude from our analysis that while
comebacks frequently occur after a run, it is slightly disadvantageous to call
a timeout during a run by the opposing team and further demonstrate that the
magnitude of this effect varies by franchise
Diagnostic Performance of Receptor-Specific Surgical Specimen Staining Correlates with Receptor Expression Level
Intraoperative margin assessment is imperative to cancer cure but is a continued challenge to successful surgery. Breast conserving surgery is a relevant example, where a cosmetically improved outcome is gained over mastectomy, but re-excision is required in \u3e25  %   of cases due to positive or closely involved margins. Clinical translation of margin assessment modalities that must directly contact the patient or required administered contrast agents are time consuming and costly to move from bench to bedside. Tumor resections provide a unique surgical opportunity to deploy margin assessment technologies including contrast agents on the resected tissues, substantially shortening the path to the clinic. However, staining of resected tissues is plagued by nonspecific uptake. A ratiometric imaging approach where matched targeted and untargeted probes are used for staining has demonstrated substantially improved biomarker quantification over staining with conventional targeted contrast agents alone. Our group has developed an antibody-based ratiometric imaging technology using fluorescently labeled, spectrally distinct targeted and untargeted antibody probes termed dual-stain difference specimen imaging (DDSI). Herein, the targeted biomarker expression level and pattern are evaluated for their effects on DDSI diagnostic potential. Epidermal growth factor receptor expression level was correlated to DDSI diagnostic potential, which was found to be robust to spatial pattern expression variation. These results highlight the utility of DDSI for accurate margin assessment of freshly resected tumor specimens
Optimizing Fresh Specimen Staining for Rapid Identification of Tumor Biomarkers During Surgery.
Rationale: Positive margin status due to incomplete removal of tumor tissue during breast conserving surgery (BCS) is a prevalent diagnosis usually requiring a second surgical procedure. These follow-up procedures increase the risk of morbidity and delay the use of adjuvant therapy; thus, significant efforts are underway to develop new intraoperative strategies for margin assessment to eliminate re-excision procedures. One strategy under development uses topical application of dual probe staining and a fluorescence imaging strategy termed dual probe difference specimen imaging (DDSI). DDSI uses a receptor-targeted fluorescent probe and an untargeted, spectrally-distinct fluorescent companion imaging agent topically applied to fresh resected specimens, where the fluorescence from each probe is imaged and a normalized difference image is computed to identify tumor-target distribution in the specimen margins. While previous reports suggested this approach is a promising new tool for surgical guidance, advancing the approach into the clinic requires methodical protocol optimization and further validation.
Methods: In the present study, we used breast cancer xenografts and receiver operator characteristic (ROC) curve analysis to evaluate a wide range of staining and imaging parameters, and completed a prospective validation study on multiple tumor phenotypes with different target expression. Imaging fluorophore-probe pair, concentration, and incubation times were systematically optimized using n=6 tissue specimen replicates per staining condition. Resulting tumor vs. normal adipose tissue diagnostic performance were reported and staining patterns were validated via receptor specific immunohistochemistry colocalization. Optimal staining conditions were tested in receptor positive and receptor negative cohorts to confirm specificity.
Results: The optimal staining conditions were found to be a one minute stain in a 200 nM probe solution (area under the curve (AUC) = 0.97), where the choice of fluorescent label combination did not significantly affect the diagnostic performance. Using an optimal threshold value determined from ROC curve analysis on a training data set, a prospective study on xenografts resulted in an AUC=0.95 for receptor positive tumors and an AUC = 0.50 for receptor negative (control) tumors, confirming the diagnostic performance of this novel imaging technique.
Conclusions: DDSI provides a robust, molecularly specific imaging methodology for identifying tumor tissue over benign mammary adipose tissue. Using a dual probe imaging strategy, nonspecific accumulation of targeted probe was corrected for and tumor vs. normal tissue diagnostic potential was improved, circumventing difficulties with ex vivotissue specimen staining and allowing for rapid clinical translation of this promising technology for tumor margin detection during BCS procedures
Clinically relevant dual probe difference specimen imaging (DDSI) protocol for freshly resected breast cancer specimen staining
Background: Re-excision rates following breast conserving surgery (BCS) remain as high as ~ 35%, with positive margins detected during follow-up histopathology. Additional breast cancer resection surgery is not only taxing on the patient and health care system, but also delays adjuvant therapies, increasing morbidity and reducing the likelihood of a positive outcome. The ability to precisely resect and visualize tumor margins in real time within the surgical theater would greatly benefit patients, surgeons and the health care system. Current tumor margin assessment technologies utilized during BCS involve relatively lengthy and labor-intensive protocols, which impede the surgical work flow. Methods: In previous work, we have developed and validated a fluorescence imaging method termed dual probe difference specimen imaging (DDSI) to accurately detect benign and malignant tissue with direct correlation to the targeted biomarker expression levels intraoperatively. The DDSI method is currently on par with touch prep cytology in execution time (~ 15-min). In this study, the main goal was to shorten the DDSI protocol by decreasing tissue blocking and washing times to optimize the DDSI protocol to \u3c 10-min whilst maintaining robust benign and malignant tissue differentiation. Results: We evaluated the utility of the shortened DDSI staining methodology using xenografts grown from cell lines with varied epidermal growth factor receptor (EGFR) expression levels, comparing accuracy through receiver operator characteristic (ROC) curve analyses across varied tissue blocking and washing times. An optimized 8-min DDSI methodology was developed for future clinical translation. Conclusions: Successful completion of this work resulted in substantial shortening of the DDSI methodology for use in the operating room, that provided robust, highly receptor specific, sensitive diagnostic capabilities between benign and malignant tissues
Far-Red and Near-Infrared Seminaphthofluorophores for Targeted Pancreatic Cancer Imaging
Molecular probes that selectively highlight pancreatic cancer (PC) tissue have the potential to improve pancreatic ductal adenocarcinoma (PDAC) margin assessment through the selective highlighting of individual PC cells. Herein, we report a simple and unique family of systematically modified red and near-infrared fluorescent probes that exhibit a field-effect-derived redshift. Two of thirteen probes distributed to the normal mouse pancreas following systemic administration. One selectively accumulated in genetically modified mouse models of PDAC. The probe exhibited intracellular accumulation and enabled visualization of four levels of the structure, including the whole organ, resected tissue, individual cells, and subcellular organelles. In contrast to the small-molecule probes reported previously, it possesses an inherent affinity toward PDAC cells and thus does not require conjugation to any targeting agent. The fluorescent probe can thus promote new strategies not only for precision image-guided surgery, but also for PC detection, monitoring of therapeutic outcomes, and basic research
Use of interplay between A-site non-stoichiometry and hydroxide doping to deliver novel proton-conducting perovskite oxides
Funding: UK Engineering and Physical Sciences Research Council (Grant Number(s): EP/R023522, EP/R023751, EP/L017008, EP/P007821, EP/L000202, EP/R029431); Diamond Light Source (Grant Number(s): SP17198-8); Rutherford Appleton Laboratory (Grant Number(s): RB1920629).The magnitude of ionic conductivity is known to depend upon both mobility and number of available carriers. For proton conductors, hydration is a key factor in determining the charge–carrier concentration in ABO3 perovskite oxides. Despite the high reported proton mobility of calcium titanate (CaTiO3), this titanate perovskite has thus far been regarded as a poor proton conductor due to the low hydration capability. Here, the enhanced proton conductivity of the defective calcium titanate Ca0.92TiO2.84(OH)0.16 prepared by replacing lattice oxygens with hydroxyl groups via a solvothermal route is shown. Conductivity measurements in a humidified Ar atmosphere reveal that, remarkably, this material exhibits one order of magnitude higher bulk conductivity (10−4 Scm−1 at 200 °C) than hydrated stoichiometric CaTiO3 prepared by traditional solid-state synthesis due to the higher concentration of protonic defects and variation in the crystal structure. The replacement of Ca2+ by Ni2+ in the Ca1−xTi1O3−2x(OH)2x, which mostly exsolve metallic Ni nanoparticles along orthorhombic (100) planes upon reduction, is also demonstrated. These results suggest a new strategy by tailoring the defect chemistry via hydration or cation doping followed by exsolution for targeted energy applications.Publisher PDFPeer reviewe
The Grizzly, October 13, 2011
UCARE Draws More Blood, Donors • Ursinus is Talking About Author Speaks on Novel • Annual Security and Fire Safety Report Released • Alcohol-Related Hospitalizations Rise, Confuse Administration • Berman Exhibit Honors Muhlenberg Family • Ursinus GSA Provides Genuine Acceptance for All • UC\u27s Dr. Clouser Lectures on Birds\u27 Habitats • Renaissance Band Takes Students Back in Time • Opinion: New Law in Alabama Intrudes on Citizens; Tips to Avoiding the Feared Freshman 15 • UC Water Polo Stresses Fun Over Seriousness • Men\u27s Soccer Gears Up for the Stretch Run • UC Rugby Making Bigger Commitmenthttps://digitalcommons.ursinus.edu/grizzlynews/1843/thumbnail.jp
The Grizzly, October 6, 2011
Fong, CPPC Developing Strategic Plan • Study Abroad Undergoes Major Changes, Relocation • Art Department Sponsors Trip to New York City • Residence Life Sponsors First-Ever Sexual Olympics • Senior Spends Summer Researching Parkinson\u27s • International Film Festival: A Glimpse Into Other Cultures • Wismer on Wheels Offers Helping Hand • Club Promotes Suicide Awareness • Anti-anxiety Group Aims to Relieve Stress • UC Club Soccer Kicks Off First Full Season • UC Fencing Club Looking to Increase its Numbers • Coach Profile: Mark Feinberg, Swimminghttps://digitalcommons.ursinus.edu/grizzlynews/1842/thumbnail.jp
Calibrating CHIME, A New Radio Interferometer to Probe Dark Energy
The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a transit
interferometer currently being built at the Dominion Radio Astrophysical
Observatory (DRAO) in Penticton, BC, Canada. We will use CHIME to map neutral
hydrogen in the frequency range 400 -- 800\,MHz over half of the sky, producing
a measurement of baryon acoustic oscillations (BAO) at redshifts between 0.8 --
2.5 to probe dark energy. We have deployed a pathfinder version of CHIME that
will yield constraints on the BAO power spectrum and provide a test-bed for our
calibration scheme. I will discuss the CHIME calibration requirements and
describe instrumentation we are developing to meet these requirements
Canadian Hydrogen Intensity Mapping Experiment (CHIME) Pathfinder
A pathfinder version of CHIME (the Canadian Hydrogen Intensity Mapping
Experiment) is currently being commissioned at the Dominion Radio Astrophysical
Observatory (DRAO) in Penticton, BC. The instrument is a hybrid cylindrical
interferometer designed to measure the large scale neutral hydrogen power
spectrum across the redshift range 0.8 to 2.5. The power spectrum will be used
to measure the baryon acoustic oscillation (BAO) scale across this poorly
probed redshift range where dark energy becomes a significant contributor to
the evolution of the Universe. The instrument revives the cylinder design in
radio astronomy with a wide field survey as a primary goal. Modern low-noise
amplifiers and digital processing remove the necessity for the analog
beamforming that characterized previous designs. The Pathfinder consists of two
cylinders 37\,m long by 20\,m wide oriented north-south for a total collecting
area of 1,500 square meters. The cylinders are stationary with no moving parts,
and form a transit instrument with an instantaneous field of view of
100\,degrees by 1-2\,degrees. Each CHIME Pathfinder cylinder has a
feedline with 64 dual polarization feeds placed every 30\,cm which
Nyquist sample the north-south sky over much of the frequency band. The signals
from each dual-polarization feed are independently amplified, filtered to
400-800\,MHz, and directly sampled at 800\,MSps using 8 bits. The correlator is
an FX design, where the Fourier transform channelization is performed in FPGAs,
which are interfaced to a set of GPUs that compute the correlation matrix. The
CHIME Pathfinder is a 1/10th scale prototype version of CHIME and is designed
to detect the BAO feature and constrain the distance-redshift relation.Comment: 20 pages, 12 figures. submitted to Proc. SPIE, Astronomical
Telescopes + Instrumentation (2014
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