2,853 research outputs found
Real-time tissue viability assessment using near-infrared light
Despite significant advances in medical imaging technologies, there currently exist no tools to effectively assist healthcare professionals during surgical procedures. In turn, procedures remain subjective and dependent on experience, resulting in avoidable failure and significant quality of care disparities across hospitals.
Optical techniques are gaining popularity in clinical research because they are low cost, non-invasive, portable, and can retrieve both fluorescence and endogenous contrast information, providing physiological information relative to perfusion, oxygenation, metabolism, hydration, and sub-cellular content. Near-infrared (NIR) light is especially well suited for biological tissue and does not cause tissue damage from ionizing radiation or heat.
My dissertation has been focused on developing rapid imaging techniques for mapping endogenous tissue constituents to aid surgical guidance. These techniques allow, for the first time, video-rate quantitative acquisition over a large field of view (> 100 cm2) in widefield and endoscopic implementations. The optical system analysis has been focused on the spatial-frequency domain for its ease of quantitative measurements over large fields of view and for its recent development in real-time acquisition, single snapshot of optical properties (SSOP) imaging.
Using these methods, this dissertation provides novel improvements and implementations to SSOP, including both widefield and endoscopic instrumentations capable of video-rate acquisition of optical properties and sample surface profile maps. In turn, these measures generate profile-corrected maps of hemoglobin concentration that are highly beneficial for perfusion and overall tissue viability. Also utilizing optical property maps, a novel technique for quantitative fluorescence imaging was also demonstrated, showing large improvement over standard and ratiometric methods. To enable real-time feedback, rapid processing algorithms were designed using lookup tables that provide a 100x improvement in processing speed. Finally, these techniques were demonstrated in vivo to investigate their ability for early detection of tissue failure due to ischemia. Both pre-clinical studies show endogenous contrast imaging can provide early measures of future tissue viability.
The goal of this work has been to provide the foundation for real-time imaging systems that provide tissue constituent quantification for tissue viability assessments.2018-01-09T00:00:00
The Grizzly, October 30, 1981
Founders Day 100th Year of Coeducation • Board of Directors Approve Tuition Increase • Stevens Talks on Hazing to Packed House • Comment: What Eileen Stevens Didn\u27t Say • Drexel-Ursinus Offer Evening Courses at Limerick and UC • Old Men\u27s Undergoes Heating Renovations • ZX Business Society Grows • Lee Savary: Contrasting Natural and Man-made • Study Abroad Series: Seize the Day • Law of the Sea, Law of the Nations • Gridders to Enter New League in 1983 • Bears Lose Homecoming Heartbreaker • X-Country: 38 Straight W\u27s • Field Hockey Trips West Chester 3-0https://digitalcommons.ursinus.edu/grizzlynews/1065/thumbnail.jp
Comparative Assessment of the Effect of Synthetic and Natural Fungicides on Soil Respiration
As toxic pesticide residues may persist in agricultural soils and cause environmental pollution, research on natural fungicides to replace the synthetic compounds is currently increasing. The effect of the synthetic fungicide chlorothalonil and a natural potential fungicide on the soil microbial activity was evaluated here by the substrate-induced respiration by addition of glucose (SIR), as bioindicator in two soils (Eutrophic Humic Gley—GHE and Typic Eutroferric Chernosol—AVEC). The induced soil respiration parameter was followed during 28 days after soil treatment either with chlorathalonil (11 μg·g−1), or the methanolic fraction from Polymnia sonchifolia extraction (300 μg·g−1), and 14C-glucose (4.0 mg and 5.18 Bq of 14C-glucose g−1). The 14C-CO2 produced by the microbial respiration was trapped in NaOH (0.1 M) which was changed each two hours during the first 10 h, and 1, 3, 5, 7, 14 and 28 days after the treatments. The methanolic fraction of the plant extract inhibited (2.2%) and stimulated (1.8%) the respiration of GHE and AVEC, respectively, but the synthetic chlorothalonil caused 16.4% and 2.6% inhibition of the respiration, respectively of the GHE and AVEC soils. As the effects of the natural product were statistically small, this bioindicator indicates that the methanolic fraction of the Polymnia sonchifolia extract, which has fungicide properties, has no environmental effects
The Grizzly, September 18, 1981
Thomas P. Glassmoyer Elected Board President • APO Retains Highest GPA Last Spring • Chemistry, Economics, History and English Departments Receive New Faculty • Forum Programs Now \u27til Christmas • Editorial: Just Like the Good Old Days? • Message From the President: Play an Active Part • Evening in Photography Offered • Evening School Expands Computer Program • New Staff Appointments • Dr. Schultze Represents UC in Conference • UC Buying Up Main Street: New Off-Campus Housing • Anarchy in America: Let\u27s Kill All the Lawyers • Decatur Follows Shakespeare to Germany • Electric Factory Does it Again • IFC Getting it All Together • USGA Notes • Six New Faculty • Improving Relationships and Self-Image Workshop • Lacrosse Club Announces Fall Season • Gridders Kick Off \u2781 Season With Victory • Field Hockey Looking Good • Cross Country Team Off to Fast Starthttps://digitalcommons.ursinus.edu/grizzlynews/1060/thumbnail.jp
Wirtschaftspolitik und wirtschaftliche Aussichten in den Industrieländern
Der vorliegende Bericht, der neunte in dieser Reihe, ist das Ergebnis einer Konferenz unabhängiger Ökonomen aus Japan, Westeuropa und Nordamerika. Wie auch im letzten Jahr, stand die Wirtschaftspolitik, die in den Ländern dieser drei Regionen betrieben wurde, im Mittelpunkt der Gespräche. Die Konferenz fand vom 2. -4. November 1977 bei der Brookings Institution in Washington unter dem Vorsitz des Unterzeichneten statt und wurde vom Institut für Weltwirtschaft, dem Japan Economic Research Center und der Brookings Institution gefördert. Die wirtschaftspolitischen Ergebnisse dieser Tagung wurden in einer Pressemitteilung zusammengefaßt und veröffentlicht. Dieser Bericht gibt Auskunft über den Hintergrund, auf dem die wirtschaftspolitischen Empfehlungen zustande kamen. Der erste Abschnitt beschreibt die wirtschaftliche Entwicklung während des vergangenen Jahres in jeder der drei Regionen. Dabei wird der Tatsache Rechnung getragen, daß die wirtschaftliche Entwicklung dieser Länder sowohl Gemeinsamkeiten als auch Unterschiede aufweist. Anschließend wird ein Ausblick für das kommende Jahr gegeben, und die wechselseitigen Einflüsse zwischen den Regionen werden kurz untersucht. Danach folgt eine Diskussion jener Probleme, die in allen oder zumindest den meisten Ländern bestehen und einer befriedigenderen wirtschaftlichen Entwicklung im Wege stehen. Der Bericht endet mit der Darstellung der wirtschaftspolitischen Empfehlungen der Gruppe. Die Tagung und dieser Bericht wurden durch die Förderung durch den German Marshall Fund ermöglicht, dessen Präsident, Robert Gerald Livingston, der Konferenz beiwohnte. Die Teilnehmer der Konferenz, die die wirtschaftspolitischen Empfehlungen erarbeiteten, taten dies im eigenen Namen, nicht aber für die Institute, denen sie angehören. Dieser Bericht wird in Europa vom Institut für Weltwirtschaft, in Japan vom Japan Economic Research Center und in Nordamerika von der Brookings Institution publiziert. --
The Grizzly, October 2, 1981
Homecoming Celebration Takes on New Meaning • Previously Idle Appeals Procedure Finally Tested • Faculty Member\u27s Dismissal Creates Unrest • President Calls School Start \u27One of the Best Ever\u27 • Comment: I Thought This Was College • Parent Involvement Sought in Planning for the Future • Platforms for Freshman Class Elections • Greaseband Sings its Heart Out to Fortunate Few • Concert Causes Funds Loss • Transplanted Texan: Our Most Illustrious Non-Graduate • Rolling Stones Rock \u27n Roll Circus Levels JFK • Ursinus News Briefs: Postage hike finally granted; \u27Dealing with Stress\u27 offered by evening school • Campus Craziness: Sorority Pledging Begins • Red Cross Bloodmobile at HH • Women Receive Special Attention for Founder\u27s Day • Parents Day: Oct. 10 • Volleyball Holding Even • Soccer Registers First Win • Bears Surrender Lead to Tie Moravian at 10 • Hockey Pulls Out Win in Last Seconds • X-Country Makes it Look Easy . . . Againhttps://digitalcommons.ursinus.edu/grizzlynews/1062/thumbnail.jp
The Grizzly, September 25, 1981
Greaseband Tonight • Campus Welcome • Fridge Fee Unfrozen • Deutsch und Deutschland Heute: German Professor Co-authors Text • Public Speaking Exemption Exam • Books Sought by Ursinus Friends • Red Cross Bloodmobile at Helfferich Hall • Career Planning and Placement Office • Dessert Held in Union • Fast Food Service Losing Convenience • ProTheatre: Canterbury Tales Presented • Transplanted Texan: Nobody Expects the Moral Majority • School Bands Looking for Musicians • WRUC: Back on the Air? • First Coffeehouse Sparkles With Talent • Late Mail for Off-Campus Houses • [Reprinted Articles About the Greaseband] • Bear\u27s Booters Kick Off Season • Business as Usual for Cross-Country • Bears Drop 10-3 Decision to Western Maryland • Davis Leads Hockey Over Widenerhttps://digitalcommons.ursinus.edu/grizzlynews/1061/thumbnail.jp
The TESS-Keck Survey. XVI. Mass Measurements for 12 Planets in Eight Systems
With JWST's successful deployment and unexpectedly high fuel reserves,
measuring the masses of sub-Neptunes transiting bright, nearby stars will soon
become the bottleneck for characterizing the atmospheres of small exoplanets
via transmission spectroscopy. Using a carefully curated target list and more
than two years' worth of APF-Levy and Keck-HIRES Doppler monitoring, the
TESS-Keck Survey is working toward alleviating this pressure. Here we present
mass measurements for 11 transiting planets in eight systems that are
particularly suited to atmospheric follow-up with JWST. We also report the
discovery and confirmation of a temperate super-Jovian-mass planet on a
moderately eccentric orbit. The sample of eight host stars, which includes one
subgiant, spans early-K to late-F spectral types ( 5200--6200
K). We homogeneously derive planet parameters using a joint photometry and
radial velocity modeling framework, discuss the planets' possible bulk
compositions, and comment on their prospects for atmospheric characterization.Comment: Accepted for publication in The Astronomical Journal on 2023-Jun-22.
60 pages, 17 Tables, 28 Figure
The TESS-Keck Survey. XV. Precise Properties of 108 TESS Planets and Their Host Stars
We present the stellar and planetary properties for 85 TESS Objects of
Interest (TOIs) hosting 108 planet candidates which comprise the TESS-Keck
Survey (TKS) sample. We combine photometry, high-resolution spectroscopy, and
Gaia parallaxes to measure precise and accurate stellar properties. We then use
these parameters as inputs to a lightcurve processing pipeline to recover
planetary signals and homogeneously fit their transit properties. Among these
transit fits, we detect significant transit-timing variations among at least
three multi-planet systems (TOI-1136, TOI-1246, TOI-1339) and at least one
single-planet system (TOI-1279). We also reduce the uncertainties on
planet-to-star radius ratios across our sample, from a median
fractional uncertainty of 8.8 among the original TOI Catalog values to
3.0 among our updated results. With this improvement, we are able to
recover the Radius Gap among small TKS planets and find that the topology of
the Radius Gap among our sample is broadly consistent with that measured among
Kepler planets. The stellar and planetary properties presented here will
facilitate follow-up investigations of both individual TOIs and broader trends
in planet properties, system dynamics, and the evolution of planetary systems.Comment: Accepted at The Astronomical Journal; 21 pages, 9 figure
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
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