4,640 research outputs found
Miniature Resistance Measurement Device for Structural Health Monitoring of Reinforced Concrete Infrastructure
A vast amount of civil infrastructure is constructed using reinforced concrete, which can be susceptible to corrosion, posing significant risks. Corrosion of reinforced concrete has various causes, with chloride ingress known to be a major contributor. Monitoring this chloride ingress would allow for preventative maintenance to be less intrusive at a lower cost. Currently, chloride sensing methods are bulky and expensive, leaving the majority of concrete infrastructures unmonitored. This paper presents the design and fabrication of a miniature, low-cost device that can be embedded into concrete at various locations and depths. The device measures localized concrete resistance, correlating to the chloride ingress in the concrete using equations listed in this paper, and calculated results from two experiments are presented. The device benefits from a four-probe architecture, injecting a fixed frequency AC waveform across its outer electrodes within the cement block. Voltage across the internal electrodes is measured with a microcontroller and converted to a resistance value, communicated serially to an external computer. A final test showcases the ability of the device for three-dimensional mass deployment
International standardisation of the test of masticating and swallowing solids in children
The Test of Masticating and Swallowing Solids (TOMASS) is a validated assessment tool measuring the efficiency of solid bolus intake by four quantitative parameters: discrete bites, masticatory cycles, swallows and time to ingest a single cracker. A normative database for adults (20-80+ years) has previously been established. The objective of this study was to investigate the applicability and reliability of the TOMASS in children and adolescents (TOMASS-C) and to establish the normative database for this younger population. We collected data from 638 participants (male: 311, female: 327) in five age groups (4-18\ua0years) with five different but very similar test crackers in four countries. Significant effects of bolus type (cracker), age group and gender on the TOMASS parameters were identified, requiring stratification of the TOMASS-C database by these variables. Intra-rater reliability was excellent (ICC\ua0>\ua00.94) for all parameters; inter-rater reliability was moderate for "number of swallows" (ICC\ua0=\ua00.54), good for "bites" (ICC\ua0=\ua00.78) and "time" (ICC\ua0=\ua00.82), and excellent for "masticatory cycles" (ICC\ua0=\ua00.96). The "Test of Masticating and Swallowing Solids in Children (TOMASS-C)" was identified to be a reliable diagnostic tool for the comprehensive measurement of discrete oral stage components of solid bolus ingestion, standardised by a large normative database that covers age groups from preschoolers to young adults. While differences between gender groups were less pronounced than in the adult population, previous results relating to changes in masticatory and swallowing as a function of age are confirmed by our data
Increase in Clostridium difficile–related Mortality Rates, United States, 1999–2004
Reported mortality rates from Clostridium difficile disease in
the United States increased from 5.7 per million population in 1999 to 23.7 per
million in 2004. Increased rates may be due to emergence of a highly virulent
strain of C. difficile. Rates were higher for whites than for
other racial/ethnic groups
Single Electron Elliptic Flow Measurements in Au+Au Collisions from STAR
Recent measurements of elliptic flow (v_2) and the nuclear modification
factor (R_{CP}) of strange mesons and baryons in the intermediate p_T domain in
Au+Au collisions demonstrate a scaling with the number of constituent-quarks.
This suggests hadron production via quark coalescence from a thermalized parton
system. Measuring the elliptic flow of charmed hadrons, which are believed to
originate rather from fragmentation than from coalescence processes, might
therefore change our view of hadron production in heavy ion collisions.
While direct v_2 measurements of charmed hadrons are currently not available,
single electron v_2 at sufficiently high transverse momenta can serve as a
substitute. At transverse momenta above 2 GeV/c, the production of single
electrons from non-photonic sources is expected to be dominated by the decay of
charmed hadrons. Simulations show a strong correlation between the flow of the
charmed hadrons and the flow of their decay electrons for p_T > 2 GeV/c.
We will present preliminary STAR results from our single electron v_2
measurements from Au+Au collisions at RHIC energies.Comment: 10 pages, 7 figures Proceedings of the Hot Quarks 2004 Conference,
July 18-24 2004, Taos Valley, New Mexico, USA to be published in Journal of
Physics
Regulation of the Epstein-Barr virus DNA polymerase gene.
The gene (pol) encoding the Epstein-Barr virus (EBV) DNA polymerase is a member of the "early" class of viral genes which are expressed shortly after activation of latent virus infection. First, mRNA from the EBV-producing cell line, B95-8, treated with 12-O-tetradecanoylphorbol-13-acetate and sodium butyrate to induce lytic replication and expression of this gene was analyzed. Northern (RNA) analysis revealed a message of 3.7 kb found only in induced cells. 5' mapping of pol mRNA by S1 nuclease and primer extension analyses indicates that transcription initiates at tightly clustered sites within a G + C-rich region 126 bp upstream of the open reading frame. The same initiation region was identified in two other EBV-infected cell lines, P3HR1 and Raji, after induction. Second, a 1.29-kb genomic fragment containing this region, when cloned upstream of the chloramphenicol acetyltransferase reporter gene, demonstrated promoter activity in lymphoid cells cotransfected with pEBV-RZ, a genomic expression construct that includes genes for the EBV immediate-early transactivator proteins, BZLF-1 and BRLF-1. Within the upstream 1.29-kb sequence, two regions of 140 bp and 101 bp appear to be needed for promoter activity. These results demonstrate that unlike most EBV genes studied thus far, the pol gene contains multiple transcriptional start sites. The upstream regulatory region of the promoter for the pol gene does not contain canonical promoter elements such as TATA and CAAT boxes and, furthermore, is not constitutively active but requires transactivation by two or more viral proteins
SPIRITS 16tn in NGC 3556: A heavily obscured and low-luminosity supernova at 8.8 Mpc
We present the discovery by the SPitzer InfraRed Intensive Transients Survey
(SPIRITS) of a likely supernova (SN) in NGC 3556 at only 8.8 Mpc, which,
despite its proximity, was not detected by optical searches. A luminous
infrared (IR) transient at mag (Vega), SPIRITS 16tn is
coincident with a dust lane in the inclined, star-forming disk of the host.
Using IR, optical, and radio observations, we attempt to determine the nature
of this event. We estimate 8 - 9 mag of extinction, placing it
among the three most highly obscured IR-discovered SNe to date. The [4.5] light
curve declined at a rate of 0.013 mag day, and the color
grew redder from 0.7 to 1.0 mag by 184.7 days post discovery.
Optical/IR spectroscopy shows a red continuum, but no clearly discernible
features, preventing a definitive spectroscopic classification. Deep radio
observations constrain the radio luminosity of SPIRITS 16tn to erg s Hz between 3 - 15 GHz, excluding many
varieties of radio core-collapse SNe. A type Ia SN is ruled out by the observed
red IR color, and lack of features normally attributed to Fe-peak elements in
the optical and IR spectra. SPIRITS 16tn was fainter at [4.5] than typical
stripped-envelope SNe by 1 mag. Comparison of the spectral energy
distribution to SNe II suggests SPIRITS 16tn was both highly obscured, and
intrinsically dim, possibly akin to the low-luminosity SN 2005cs. We infer the
presence of an IR dust echo powered by a peak luminosity of the transient of erg s erg s,
consistent with the observed range for SNe II. This discovery illustrates the
power of IR surveys to overcome the compounding effects of visible extinction
and optically sub-luminous events in completing the inventory of nearby SNe.Comment: 25 pages, 10 figures, submitted to Ap
Minimum Information about a Neuroscience Investigation (MINI) Electrophysiology
This module represents the formalized opinion of the authors and the CARMEN consortium, which identifies the minimum information required to report the use of electrophysiology in a neuroscience study, for submission to the CARMEN system (www.carmen.org.uk).

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