Objective
The objectives of the study were to optimize three cartilage-dedicated sequences for in vivo knee imaging at 7.0 T ultra-high-field (UHF) magnetic resonance imaging (MRI) and to compare ...imaging performance and diagnostic confidence concerning osteoarthritis (OA)-induced changes at 7.0 and 3.0 T MRI.
Materials and methods
Optimized MRI sequences for cartilage imaging at 3.0 T were tailored for 7.0 T: an intermediate-weighted fast spin-echo (IM-w FSE), a fast imaging employing steady-state acquisition (FIESTA) and a T1-weighted 3D high-spatial-resolution volumetric fat-suppressed spoiled gradient-echo (SPGR) sequence. Three healthy subjects and seven patients with mild OA were examined. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), diagnostic confidence in assessing cartilage abnormalities, and image quality were determined. Abnormalities were assessed with the whole organ magnetic resonance imaging score (WORMS). Focal cartilage lesions and bone marrow edema pattern (BMEP) were also quantified.
Results
At 7.0 T, SNR was increased (
p
< 0.05) for all sequences. For the IM-w FSE sequence, limitations with the specific absorption rate (SAR) required modifications of the scan parameters yielding an incomplete coverage of the knee joint, extensive artifacts, and a less effective fat saturation. CNR and image quality were increased (
p
< 0.05) for SPGR and FIESTA and decreased for IM-w FSE. Diagnostic confidence for cartilage lesions was highest (
p
< 0.05) for FIESTA at 7.0 T. Evaluation of BMEP was decreased (
p
< 0.05) at 7.0 T due to limited performance of IM-w FSE.
Conclusion
Gradient echo-based pulse sequences like SPGR and FIESTA are well suited for imaging at UHF which may improve early detection of cartilage lesions. However, UHF IM-w FSE sequences are less feasible for clinical use.
There is a critical gap in our nation's ability to accurately measure and manage the quality of medical care. A robust healthcare quality information system (HQIS) has the potential to address this ...deficiency through the capture, codification, and analysis of information about patient treatments and related outcomes. Because non-technical issues often present the greatest challenges, this paper provides an overview of these socio-technical issues in building a successful HQIS, including the human, organizational, and knowledge management (KM) perspectives. Through an extensive literature review and direct experience in building a practical HQIS (the National Comprehensive Cancer Network Outcomes Research Database system), we have formulated an "informatics blueprint" to guide the development of such systems. While the blueprint was developed to facilitate healthcare quality information collection, management, analysis, and reporting, the concepts and advice provided may be extensible to the development of other types of clinical research information systems.
What Does the Geometry of the Hβ BLR Depend On? Villafaña, Lizvette; Williams, Peter R.; Treu, Tommaso ...
Astrophysical journal/The Astrophysical journal,
05/2023, Letnik:
948, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Abstract
We combine our dynamical modeling black-hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover ...individual scale factors,
f
, used in traditional reverberation-mapping analyses. We extend our sample by including prior results from Code for AGN Reverberation and Modeling of Emission Lines (
caramel
) studies that have utilized our methods. Aiming to improve the precision of black-hole mass estimates, as well as uncover any regularities in the behavior of the broad-line region (BLR), we search for correlations between
f
and other AGN/BLR parameters. We find (i) evidence for a correlation between the virial coefficient
log
10
(
f
mean
,
σ
)
and black-hole mass, (ii) marginal evidence for a similar correlation between
log
10
(
f
rms
,
σ
)
and black-hole mass, (iii) marginal evidence for an anticorrelation of BLR disk thickness with
log
10
(
f
mean
,
FWHM
)
and
log
10
(
f
rms
,
FWHM
)
, and (iv) marginal evidence for an anticorrelation of inclination angle with
log
10
(
f
mean
,
FWHM
)
,
log
10
(
f
rms
,
σ
)
, and
log
10
(
f
mean
,
σ
)
. Last, we find marginal evidence for a correlation between line-profile shape, when using the root-mean-square spectrum,
log
10
(
FWHM
/
σ
)
rms
, and the virial coefficient,
log
10
(
f
rms
,
σ
)
, and investigate how BLR properties might be related to line-profile shape using
caramel
models.
The adenine nucleotide transporter 1 gene (ANT1) encodes an inner mitochondrial membrane protein that transports ATP into the cell. Mutations within ANT1 produce a syndrome of chronic progressive ...external ophthalmoplegia (CPEO) in humans. Ant1 knockout (Ant1-/-) mice develop cardiomyopathy and mitochondrial myopathy of limb muscles. Because the extraocular muscles (EOM) are preferentially affected in human CPEO, the objective of this study was to determine whether Ant1-/- mice also exhibit an EOM mitochondrial myopathy.
ANT isoform expression of isolated EOMs, EOM morphology and mitochondrial content, mitochondrial structure and function, ocular motility in intact mice, and contractile performance in isolated muscle preparations were examined.
Ant1-/- EOMs had the typical appearance of mitochondrial myopathy, including increase in mitochondrial size, number, and oxidative phosphorylation (OXPHOS) staining. However, there were no measurable ocular motor abnormalities in intact Ant1-/- mice, and their isolated EOMs did not show evidence of increased fatigability. EOMs of wild-type mice exhibited higher levels of Ant2 mRNA compared with hindlimb muscle, which may compensate for the Ant1 loss in mutant mouse EOMs and account for the normal EOM function.
The Ant1-/- mice provide a model in which to study CPEO pathology and compensatory mechanisms.
Improved Analysis of Timber Rivet Connections Stahl, Douglas C; Wolfe, Ronald W; Begel, Marshall
Journal of structural engineering (New York, N.Y.),
08/2004, Letnik:
130, Številka:
8
Journal Article
Recenzirano
Timber rivets are fasteners for glued-laminated timber construction that were first sanctioned for use in the United Stated by adoption in the 1997 National Design Specification for Wood Construction ...(NDS). Rivet connections can exhibit a brittle failure when a volume of wood bounded by the perimeter of the rivets pulls out from the timber, or a ductile failure due to a combination of fastener yielding and localized wood crushing. The NDS approach to the former failure mode is so complex that closed form solution is not possible and designers must refer to limited tabular data, and the NDS approach to the latter failure mode is inconsistent with the approach used for other dowel fasteners. This paper describes an improved analysis based on the capacity of wood failure planes and the well-established dowel fastener yield model. Results of tests of large rivet connections highlighting the crossover from ductile to brittle failure modes verify the analysis. In addition, these results provide the first data for timber rivets in Southern Pine glued-laminated timber.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Since 1989, City of Hope National Medical Center (COH), located in Duarte, California, and a member of the National Comprehensive Cancer Network, has prohibited smoking anywhere on the 100-acre ...campus. Because little published information is available on smoke-free campuses (SFCs), we investigated the attitudes of COH employees toward the SFC and attempted to answer the question of whether a difference in employee smoking behavior occurred and was attributable to the SFC policy. An anonymous survey was sent to all 2787 campus employees using both Web-based data entry and scannable paper forms. Employees with network access were contacted by e-mail and those without computers were contacted in person. Respondents were asked questions regarding their attitudes toward the SFC and about their smoking history and current smoking behavior. A total of 1356 responses (48.7%) were received. One hundred (7.4%) respondents were current smokers, 242 (17.8%) were ex-smokers, and 1014 (74.8%) were nonsmokers. Smokers and ex-smokers smoked a mean of 2.4 fewer cigarettes (95% CI, 1.8 to 3.1; P < .0001) on workdays than on days off, with evidence of a small amount of compensatory smoking (one cigarette per day). Of the smoking employees, 61.6% believed that the SFC reduced their cigarette consumption, and 42.2% quit smoking while employed at COH between 1989 and 2002. Of all respondents, 92.6% supported the COH SFC policy. High acceptance was consistent across gender, ethnicity, job type, and educational level. COH's SFC policy is strongly supported by employees and may decrease cigarette consumption and facilitate smoking cessation among smoking employees. This information may be useful to NCCN and other medical centers in assessing current and planning future campus smoking policies.
Waste wood sent to landfills represents a potentially valuable resource for construction materials. This paper reports progress in the use of recycled wood aggregate for concrete block. The project ...goal was to use standard concrete block manufacturing procedures to produce a lightweight block meeting the requirements of ASTM C129 for non-loadbearing concrete masonry. Trial cylinders were made in a laboratory simulation of block plant processes to evaluate admixtures and wood treatments, then promising mixes were used to make several batches of blocks in a commercial plant. Cylinders and blocks were tested for compressive strength, and the blocks were subjected to wet-dry cycling. Results indicate that weight, strength, and durability targets were met. Questions remain regarding the economic performance of the product, and further study is required to evaluate the effect of curing blocks in the uncontrolled exterior conditions typical of the block industry.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The 5$^{\prime}$ noncoding region of poliovirus RNA contains an internal ribosome entry site (IRES) for cap-independent initiation of translation. Utilization of the IRES requires the participation ...of one or more cellular proteins that mediate events in the translation initiation reaction, but whose biochemical roles have not been defined. In this report, we identify a cellular RNA binding protein isolated from the ribosomal salt wash of uninfected HeLa cells that specifically binds to stem-loop IV, a domain located in the central part of the poliovirus IRES. The protein was isolated by specific RNA affinity chromatography, and 55% of its sequence was determined by automated liquid chromatography-tandem mass spectrometry. The sequence obtained matched that of poly(rC) binding protein 2 (PCBP2), previously identified as an RNA binding protein from human cells. PCBP2, as well as a related protein, PCBP1, was over-expressed in Escherichia coli after cloning the cDNAs into an expression plasmid to produce a histidine-tagged fusion protein. Specific interaction between recombinant PCBP2 and poliovirus stem-loop IV was demonstrated by RNA mobility shift analysis. The closely related PCBP1 showed no stable interaction with the RNA. Stem-loop IV RNA containing a three nucleotide insertion that abrogates translation activity and virus viability was unable to bind PCBP2.
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