1,781 research outputs found
The influence of rifle carriage on the kinetics of human gait
The influence that rifle carriage has on human gait has received little attention in the published literature. Rifle carriage has two main effects, to add load to the anterior of the body and to restrict natural arm swing patterns. Kinetic data were collected from 15 male participants, with 10 trials in each of four experimental conditions. The conditions were: walking without a load (used as a control condition); carrying a lightweight rifle
simulator, which restricted arm movements but applied no additional load; wearing a 4.4 kg diving belt, which allowed arms to move freely; carrying a weighted (4.4 kg)
replica SA80 rifle. Walking speed was fixed at 1.5 m/s (+5%) and data were sampled at 400 Hz. Results showed that rifle carriage significantly alters the ground reaction forces produced during walking, the most important effects being an increase in the impact peak and mediolateral forces. This study suggests that these effects are due to the increased range of motion of the body’s centre of mass caused by the impeding of natural arm swing patterns. The subsequent effect on the potential development of injuries in rifle carriers is unknown
Design by immersion: A transdisciplinary approach to problem-driven visualizations
While previous work exists on how to conduct and disseminate insights from problem-driven visualization work and design studies, the literature does not address how to accomplish these goals in transdisciplinary teams in ways that advance all disciplines involved. In this paper we introduce and define a new methodological paradigm we call design by immersion, which provides an alternative perspective on problem-driven visualization work. Design by immersion embeds transdisciplinary experiences at the center of the visualization process by having visualization researchers participate in the work of the target domain (or domain experts participate in visualization research). Based on our own combined experiences of working on cross-disciplinary, problem-driven visualization projects, we present six case studies that expose the opportunities that design by immersion enables, including (1) exploring new domain-inspired visualization design spaces, (2) enriching domain understanding through personal experiences, and (3) building strong transdisciplinary relationships. Furthermore, we illustrate how the process of design by immersion opens up a diverse set of design activities that can be combined in different ways depending on the type of collaboration, project, and goals. Finally, we discuss the challenges and potential pitfalls of design by immersion
A novel reversed phase high performance liquid chromatography method to accurately determine low concentrations of curcumin in rat plasma
Due to its lipophilic nature, curcumin levels in plasma are very low after oral administration, and therefore hard to detect.
A number of chromatographic methods, including LC/MS have been developed. Although the LC/MS method is sensitive,
the matrix effect can be difficult to handle. Furthermore, LC/MS equipment is relatively expensive compared to the
conventional RP-HPLC. Therefore, the aim of this study was to develop a sensitive and reliable method for the
determination of curcumin concentration in plasma using an RP-HPLC. Curcuma longa extract was used which contains
three curcuminoids. The method started by selection of mobile phase to optimally separate the curcuminoids. The best
mobile phase composition was used to analyze the plasma samples. Rat plasma was spiked with curcumin and processed
for protein precipitation followed by liquid-liquid extraction of curcuminoids and an internal standard, emodin.
Chromatogaphic separation of curcuminoids and emodin was achieved using a Knauer C-18 column (250 x 4.6 mm;
particle size: 5µm) and a gradient program of mobile phase of three solvents, methanol -acetonitrile-1% acetic acid. A
gradient elution was applied with increasing the ratio of the volume percentages of acetonitrile to acetic acid from 50/45
to 53/42 during 5 minute and thereafter elution was isocratic for 15 minute. The methanol concentration was kept constant
at 5 vol-% during the whole run. The method was validated according to the FDA guidelines.The method was selective,
with an excellent resolution (Rs value > 2.5). The peak shape of both curcumin and emodin were symmetric with a tailing
factor of 0.9-1.1. The method linearity (correlation coefficient of 0.999) was demonstrated at 6 to 200 ng/mL. The intra and inter-day precision was 5.90-8.50% and 5.37-11.26%, respectively; the intra- and inter-day accuracy was 92.47-103.61% and 96.17-105.70%, respectively. In conclusion, the RP-HPLC method meets the validation requirements as described in the FDA guidelines and is applicable to accurately quantify curcumin concentrations as low as 6 ng/mL in rat plasma samples
A novel reversed phase high performance liquid chromatography method to accurately determine low concentrations of curcumin in rat plasma
Due to its lipophilic nature, curcumin levels in plasma are very low after oral administration, and therefore hard to detect.
A number of chromatographic methods, including LC/MS have been developed. Although the LC/MS method is sensitive,
the matrix effect can be difficult to handle. Furthermore, LC/MS equipment is relatively expensive compared to the
conventional RP-HPLC. Therefore, the aim of this study was to develop a sensitive and reliable method for the
determination of curcumin concentration in plasma using an RP-HPLC. Curcuma longa extract was used which contains
three curcuminoids. The method started by selection of mobile phase to optimally separate the curcuminoids. The best
mobile phase composition was used to analyze the plasma samples. Rat plasma was spiked with curcumin and processed
for protein precipitation followed by liquid-liquid extraction of curcuminoids and an internal standard, emodin.
Chromatogaphic separation of curcuminoids and emodin was achieved using a Knauer C-18 column (250 x 4.6 mm;
particle size: 5µm) and a gradient program of mobile phase of three solvents, methanol -acetonitrile-1% acetic acid. A
gradient elution was applied with increasing the ratio of the volume percentages of acetonitrile to acetic acid from 50/45
to 53/42 during 5 minute and thereafter elution was isocratic for 15 minute. The methanol concentration was kept constant
at 5 vol-% during the whole run. The method was validated according to the FDA guidelines.The method was selective,
with an excellent resolution (Rs value > 2.5). The peak shape of both curcumin and emodin were symmetric with a tailing
factor of 0.9-1.1. The method linearity (correlation coefficient of 0.999) was demonstrated at 6 to 200 ng/mL. The intra and inter-day precision was 5.90-8.50% and 5.37-11.26%, respectively; the intra- and inter-day accuracy was 92.47-103.61% and 96.17-105.70%, respectively. In conclusion, the RP-HPLC method meets the validation requirements as described in the FDA guidelines and is applicable to accurately quantify curcumin concentrations as low as 6 ng/mL in rat plasma samples
BigWig and BigBed: enabling browsing of large distributed datasets
Summary: BigWig and BigBed files are compressed binary indexed files containing data at several resolutions that allow the high-performance display of next-generation sequencing experiment results in the UCSC Genome Browser. The visualization is implemented using a multi-layered software approach that takes advantage of specific capabilities of web-based protocols and Linux and UNIX operating systems files, R trees and various indexing and compression tricks. As a result, only the data needed to support the current browser view is transmitted rather than the entire file, enabling fast remote access to large distributed data sets
Target Mass Monitoring and Instrumentation in the Daya Bay Antineutrino Detectors
The Daya Bay experiment measures sin^2 2{\theta}_13 using functionally
identical antineutrino detectors located at distances of 300 to 2000 meters
from the Daya Bay nuclear power complex. Each detector consists of three nested
fluid volumes surrounded by photomultiplier tubes. These volumes are coupled to
overflow tanks on top of the detector to allow for thermal expansion of the
liquid. Antineutrinos are detected through the inverse beta decay reaction on
the proton-rich scintillator target. A precise and continuous measurement of
the detector's central target mass is achieved by monitoring the the fluid
level in the overflow tanks with cameras and ultrasonic and capacitive sensors.
In addition, the monitoring system records detector temperature and levelness
at multiple positions. This monitoring information allows the precise
determination of the detectors' effective number of target protons during data
taking. We present the design, calibration, installation and in-situ tests of
the Daya Bay real-time antineutrino detector monitoring sensors and readout
electronics.Comment: 22 pages, 20 figures; accepted by JINST. Changes in v2: minor
revisions to incorporate editorial feedback from JINS
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