18,531 research outputs found
Addition of Sodium Bicarbonate to Irrigation Solution May Assist in Dissolution of Uric Acid Fragments During Ureteroscopy
Introduction: We hypothesized that adding sodium bicarbonate (bicarb) to normal saline (NS) irrigation during ureteroscopy in patients with uric acid (UA) nephrolithiasis may assist in dissolving small stone fragments produced during laser lithotripsy. In vitro testing was performed to determine whether dissolution of UA fragments could be accomplished within 1 hour.
Materials and Methods: In total 100% UA renal calculi were fragmented, filtered, and separated by size. Fragment sizes were <0.5 mm and 0.5 to 1 mm. Similar amounts of stone material were agitated in solution at room temperature. Four solutions were tested (NS, NS +1 ampule bicarb/L, NS +2, NS +3). Both groups were filtered to remove solutions after fixed periods. Filtered specimens were dried and weighed. Fragment dissolution rates were calculated as percent removed per hour. Additional testing was performed to determine whether increasing the temperature of solution affected dissolution rates.
Results: For fragments <0.5 mm, adding 2 or 3 bicarb ampules/L NS produced a dissolution rate averaging 91% ± 29% per hour. This rate averaged 226% faster than NS alone. With fragments 0.5 to 1 mm, addition of 2 or 3 bicarb ampules/L NS yielded a dissolution rate averaging 22% ± 7% per hour, which was nearly five times higher than NS alone. There was a trend for an increase in mean dissolution rate with higher temperature but this increase was not significant (p = 0.30).
Conclusions: The addition of bicarbonate to NS more than doubles the dissolution rate of UA stone fragments and fragments less than 0.5 mm can be completely dissolved within 1 hour. Addition of bicarb to NS irrigation is a simple and inexpensive approach that may assist in the dissolution of UA fragments produced during ureteroscopic laser lithotripsy. Further studies are needed to determine whether a clinical benefit exists
RURAL ECONOMIC DEVELOPMENT FOR COMMUNITY SELF-RELIANCE
Community/Rural/Urban Development,
Feeding Records of Aphids (Hemiptera: Aphididae) From Wisconsin
Basic to our understanding of any animal and its habitat requirements is knowing what it eats. Reported here are observations of feeding by 27 species of aphids encountered in Wisconsin over 1992-2002
Feeding Records of Aphids (Hemiptera: Aphididae) From Wisconsin, Supplement
Basic to our understanding of any animal and its habitat requirements is knowing what it eats. Reported here are observations of feeding by 24 species of aphids encountered in Wisconsin over 2002-2010
Space-based tests of gravity with laser ranging
Existing capabilities in laser ranging, optical interferometry and metrology,
in combination with precision frequency standards, atom-based quantum sensors,
and drag-free technologies, are critical for the space-based tests of
fundamental physics; as a result, of the recent progress in these disciplines,
the entire area is poised for major advances. Thus, accurate ranging to the
Moon and Mars will provide significant improvements in several gravity tests,
namely the equivalence principle, geodetic precession, PPN parameters
and , and possible variation of the gravitational constant . Other
tests will become possible with development of an optical architecture that
would allow proceeding from meter to centimeter to millimeter range accuracies
on interplanetary distances. Motivated by anticipated accuracy gains, we
discuss the recent renaissance in lunar laser ranging and consider future
relativistic gravity experiments with precision laser ranging over
interplanetary distances.Comment: 14 pages, 2 figures, 1 table. To appear in the proceedings of the
International Workshop "From Quantum to Cosmos: Fundamental Physics Research
in Space", 21-24 May 2006, Warrenton, Virginia, USA
http://physics.jpl.nasa.gov/quantum-to-cosmos
Book Review
Review of Legal Limits of Authority over the Pupil, Edward C. Bolmeier, Michie Co. 197
Reconsidering the Apologetic Purpose of Luke-Acts
The Gospel of Luke and Acts of the Apostles are two critical works in the Bible. Together, these two books make up approximately twenty seven percent of the New Testament. Their literary contribution to what is known about the origins of Christianity and its rapid spread in major cities of the Roman Empire is immeasurable. It is appropriate that so much has been written regarding these two key books’ origins, genre, and purpose. Yet, with all that has been written, there is still much debate about this subject. Should these two books be treated separately, as two different genres, or should they be treated as one unified work? Thomas Phillips does well when he states, “The question of the genre(s) of Luke and Acts may seem like a mere scholarly trifle, but one’s answer to this question does have interpretive implications.” This dissertation contends that Luke and Acts (hereafter known as Luke-Acts) is a single, continuous work, divided into two volumes. As a continuous work, this study suggests that there is an apologetic purpose behind the making of Luke-Acts, which includes defending the legitimacy of Christianity and the innocence of Paul. This purpose makes what appear to be superfluous details crucial points of evidence
Characterization of noncontact piezoelectric transducer with conically shaped piezoelement
The characterization of a dynamic surface displacement transducer (IQI Model 501) by a noncontact method is presented. The transducer is designed for ultrasonic as well as acoustic emission measurements and, according to the manufacturer, its characteristic features include a flat frequency response range which is from 50 to 1000 kHz and a quality factor Q of less than unity. The characterization is based on the behavior of the transducer as a receiver and involves exciting the transducer directly by transient pulse input stress signals of quasi-electrostatic origin and observing its response in a digital storage oscilloscope. Theoretical models for studying the response of the transducer to pulse input stress signals and for generating pulse stress signals are presented. The characteristic features of the transducer which include the central frequency f sub o, quality factor Q, and flat frequency response range are obtained by this noncontact characterization technique and they compare favorably with those obtained by a tone burst method which are also presented
Book Review
Review of Legal Limits of Authority over the Pupil, Edward C. Bolmeier, Michie Co. 197
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