bluuebunny/crossref_metadata_2025_split huggingface dataset:
Segmentation of cardiac cine MR images of left and right ventricles: Interactive semiautomated methods and manual contouring by two readers with different education and experience
Authors: Sardanelli Francesco , Quarenghi Matteo , Di Leo Giovanni , Boccaccini Leonardo , Schiavi Angelo 
Published: February 2008

AbstractPurposeTo test interactive semiautomated methods (ISAM) vs. manual contouring (MC) in segmenting cardiac cine MR images.Materials and MethodsShort‐axis images of 10 consecutive patients (1.5–81.5 years of age) were evaluated by a trained radiologist (R1) and a low‐trained engineer (R2). Each of them performed four independent reading sessions: two using ISAM and two using MC. Left ventricle (LV) myocardial mass (LVMM), LV ejection fraction (LVEF), and right ventricle (RV) ejection fraction (RVEF) were obtained. Bland‐Altman analysis and Wilcoxon test were used.ResultsThe bias ± 2 standard deviations (SD) of ISAM vs. MC for LVMM (g) was –5.7 ± 13.4 (R1) and –5.5 ± 26.3 (R2); for LVEF (%) it was –1.4 ± 13.0 and –2.9 ± and 6.8; for RVEF (%) it was 2.6 ± 17.0 and 1.0 ± 16.7. Considering both readers/methods, intraobserver bias ± 2 SD ranged from 0.3 ± 25.3 to –6.8 ± 23.0, from 0.2 ± 8.0 to –4.4 ± 15.8, and from –0.0 ± 26.4 to –4.6 ± 27.8, respectively. Interobserver bias ± 2 SD was –25.9 ± 46.0 (ISAM) and 26.1 ± 36.4 (MC), –1.4 ± 8.6 (ISAM) and 0.1 ± 17.9 (MC), and 0.7 ± 23.3 and 2.3 ± 29.8, respectively. Larger SDs were systematically found for RVEF vs. LVEF. Segmentation times: five minutes for LV with ISAM (both readers); for LV with MC, six (R1) vs. nine minutes (R2) (P < 0.001); five to six minutes for RV (both methods /readers). R2 significantly reduced LV segmentation times from nine (MC) to five minutes (ISAM) (P < 0.001).ConclusionA highly reproducible LV segmentation was performed in a short time by R1. The advantage of ISAM vs. MC for LV segmentation was a time saving only for R2. For RVEF, a lower reproducibility was observed for both methods and readers. J. Magn. Reson. Imaging 2008. © 2008 Wiley‐Liss, Inc.
White matter microstructural abnormalities in children with spina bifida myelomeningocele and hydrocephalus: A diffusion tensor tractography study of the association pathways
Authors: Hasan Khader M. , Eluvathingal Thomas J. , Kramer Larry A. , Ewing‐Cobbs Linda , Dennis Maureen , Fletcher Jack M. 
Published: February 2008

AbstractPurposeTo quantify microstructural abnormalities in the major association pathways of children affected by spina bifida myelomeningocele (SBM) and shunted hydrocephalus using whole‐brain diffusion tensor imaging (DTI).Materials and MethodsThe institutional review board approved this Health Insurance Portability and Accountability Act (HIPAA)‐compliant study and written informed consent/assent were obtained prior to the study. The 69 participants included 38 children with SBM and shunted hydrocephalus (age mean ± SD = 12.30 ± 2.10 years; 22 boys; 10 left‐handed) and 31 age‐ and sex‐matched normally‐developing children (11.56 ± 2.72 years; 15 boys, four left‐handed). Diffusion tensor tractography (DTT) was performed to delineate and quantify bilaterally four major association pathways (arcuate, inferior longitudinal, inferior frontooccipital, and uncinate fasciculi).ResultsThe group with SBM did not exhibit the pattern of age‐related decreases in the diffusivities observed in the controls. The transverse and axial diffusivities were significantly elevated in most of the white matter pathways of the participants with SBM. The fractional anisotropy (FA) was significantly lower in most of the association pathways. Many of the association pathways were not traceable in some participants with SBM compared to the controls at the selected FA thresholds.ConclusionDTT revealed diffusion tensor characteristics of abnormal development (nonvisualization/poor visualization of tracts, ↓ FA, ↑ diffusivities), impairment in myelination (↑ transverse diffusivity) as well as abnormalities in intrinsic axonal characteristics and extraaxonal/extracellular space (↑ axial diffusivity) in the association pathways of the SBM children. The differences in the diffusion metrics observed in the children with SBM are suggestive of abnormal white matter development and persistent degeneration with increased age. J. Magn. Reson. Imaging 2008. © 2008 Wiley‐Liss, Inc.
An algorithm for thorough background subtraction from high‐resolution LC/MS data: application for detection of glutathione‐trapped reactive metabolites
Authors: Zhang Haiying , Yang Yanou 
Published: February 2008

AbstractA control sample background‐subtraction algorithm was developed for thorough subtraction of background and matrix‐related signals in high‐resolution, accurate mass liquid chromatography/mass spectrometry (LC/MS) data to reveal ions of interest in an analyte sample. This algorithm checked all ions in the control scans within a specified time window around the analyte scan for potential subtraction of ions found in that analyte scan. Applying this method, chromatographic fluctuations between runs were dealt with and background and matrix‐related signals in the sample could be thoroughly subtracted. The effectiveness of this algorithm was demonstrated using four test compounds, clozapine, diclofenac, imipramine, and tacrine, to reveal glutathione (GSH)‐trapped reactive metabolites after incubation with human liver microsomes supplemented with GSH (30 µMcompound, 45‐min incubation). Using this algorithm with a ± 1.0 min control scan time window, a ± 5 ppm mass error tolerance, and appropriate control samples, the GSH‐trapped metabolites were revealed as the major peaks in the processed LC/MS profiles. Such profiles allowed for comprehensive and reliable identification of these metabolites without the need for any presumptions regarding their behavior or properties with respect to mass spectrometric detection. The algorithm was shown to provide superior results when compared to several commercially available background‐subtraction algorithms. Many of the metabolites detected were doubly charged species which would be difficult to detect with traditional GSH adduct screening techniques, and thus, some of the adducts have not previously been reported in the literature. Copyright © 2008 John Wiley & Sons, Ltd.
Polymethylmethacrylate particles inhibit osteoblastic differentiation of MC3T3‐E1 osteoprogenitor cells
Authors: Chiu Richard , Ma Ting , Smith R. Lane , Goodman Stuart B. 
Published: February 2008

AbstractOrthopedic wear debris has been implicated as a significant inhibitory factor of osteoblast differentiation. Polymethylmethacrylate (PMMA) particles have been previously shown to inhibit the differentiation of osteoprogenitors in heterogeneous murine marrow stromal cell cultures, but the effect of PMMA particles on pure osteoprogenitor populations remains unknown. In this study, we challenged murine MC3T3‐E1 osteoprogenitor cells with PMMA particles during their initial differentiation in osteogenic medium. MC3T3‐E1 cultures challenged with PMMA particles showed a gradual dose‐dependent decrease in mineralization, cell number, and alkaline phosphatase activity at low particle doses (0.038–0.150% v/v) and complete reduction of these outcome parameters at high particle doses (≥0.300% v/v). MC3T3‐E1 cultures challenged with a high particle dose (0.300% v/v) showed no rise in these outcome parameters over time, whereas cultures challenged with a low particle dose (0.075% v/v) showed a normal or reduced rate of increase compared to controls. Osteocalcin production was not significantly affected by particles at all doses tested. MC3T3‐E1 cells grown in conditioned medium from particle‐treated MC3T3‐E1 cultures showed a significant reduction in mineralization only. These results indicate that direct exposure of MC3T3‐E1 osteoprogenitors to PMMA particles results in suppression of osteogenic proliferation and differentiation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:932–936, 2008
An evaluation of the psychometric properties of the traumatic events questionnaire in primary care patients
Authors: Crawford Eric F. , Lang Ariel J. , Laffaye Charlene 
Published: February 2008

AbstractThis study examined the reliability of reports of traumatic experiences across the Traumatic Events Questionnaire (TEQ; S. Vrana & D. Lauterbach, 1994) and the Composite International Diagnostic Interview (CIDI; World Health Organization, 1998), and evaluated other psychometric properties of the TEQ in 154 primary care patients. Agreement rates for various traumatic experiences were moderate to substantial, with sexual abuse showing 87% agreement, and other forms of trauma exhibiting rates from 81–74%. The TEQ yields a trauma intensity score, which produced stronger correlations with self‐reported PTSD symptoms and problematic anger than the sum of traumas experienced. Trauma intensity also proved to be a powerful predictor of posttraumatic stress disorder (PTSD) diagnostic status. Results support the TEQ as a measure of traumatic exposure in primary care populations.
PTSD symptom clusters associated with physical health and health care utilization in rural primary care patients exposed to natural disaster
Authors: Polusny Melissa A. , Ries Barry J. , Schultz Jessica R. , Calhoun Patrick , Clemensen Lisa , Johnsen Ingrid R. 
Published: February 2008

AbstractThis study investigated the influence of exposure to a tornado disaster and disaster‐related posttraumatic stress disorder (PTSD) symptomatology on physical health complaints and primary health care utilization among rural medical patients. One‐hundred five patients completed self‐report measures assessing disaster exposure, PTSD symptoms, and self‐reported physical health complaints. Objective rates of health care utilization were gathered by a review of medical records. Tornado disaster exposure and generalized psychological distress were associated with physical health complaints one year following the disaster. After controlling for age, gender, and levels of predisaster health care utilization, PTSD Cluster C (avoidance) symptoms were associated with increased rates of postdisaster health care utilization. Implications of these findings for interventions within the medical system are discussed.
Assessing risk of violent behavior among veterans with severe mental illness
Authors: Elbogen Eric B. , Beckham Jean C. , Butterfield Marian I. , Swartz Marvin , Swanson Jeffrey 
Published: February 2008

AbstractAlthough empirical research has examined factors associated with increased violence risk among individuals with severe mental illness (SMI) and among veterans without SMI, less attention has been devoted to identifying violence risk factors among veterans with SMI. Using multivariable analysis of a large pooled sample of individuals with SMI, this study examines violence risk factors of N = 278 veterans with SMI. In multivariate modeling, violence by veterans with SMI was associated with head injury, posttraumatic stress disorder (PTSD), substance abuse, and homelessness. Results support the view clinicians assessing violence risk among veterans with SMI should consider a combination of characteristics empirically related to violence by non‐veterans with SMI (e.g., homelessness) and veterans without SMI (e.g., PTSD).
Indirect exposure to the September 11 terrorist attacks: Does symptom structure resemble PTSD?
Authors: Suvak Michael , Maguen Shira , Litz Brett T. , Silver Roxane Cohen , Holman E. Alison 
Published: February 2008

AbstractThe authors conducted confirmatory factor analyses of reports of posttraumatic stress reactions using a national probability sample of individuals indirectly exposed to the terrorist attacks of September 11, 2001 (n = 675). Reactions at three time points in the year after the attacks were best accounted for by a lower‐order, 4‐factor solution (Reexperiencing, Strategic Avoidance, Emotional Numbing, and Hyperarousal Symptoms). Indirect exposure to a traumatic event appears to induce a response with a similar symptom structure as responses to direct exposure.
Traumatized youth and substance abuse treatment outcomes: A longitudinal study
Authors: Williams Julie K. , Smith Douglas C. , Gotman Nathan , Sabri Bushra , An Hyonggin , Hall James A. 
Published: February 2008

AbstractThis longitudinal study examined whether youth with high traumatic stress (HTS) respond differently to outpatient substance abuse treatment compared to youth without HTS at intake, and at 3 and 6 months following intake. Data were analyzed using a mixed‐effects two‐part model to fit repeated data with zero saturation. Clients in both groups significantly increased their odds of abstinence and full symptom remission of substance problems from baseline to 6 months. Of youth still using substances, the group with HTS reduced substance use significantly more than substance users without HTS. Recommendations for future research are provided.
Persisting posttraumatic stress disorder symptoms and their relationship to functioning in Vietnam veterans: A 14‐year follow‐up
Authors: Koenen Karestan C. , Stellman Steven D. , Sommer John F. , Stellman Jeanne Mager 
Published: February 2008

AbstractThe authors examined the longitudinal association between persisting posttraumatic stress disorder (PTSD) symptoms and multiple domains of life functioning in a community sample of 1,377 American Legionnaire Vietnam veterans first assessed in 1984 and followed‐up 14 years later. Almost 30 years after their return from Vietnam, 10% of veterans continued to experience severe PTSD symptoms. At all levels of combat exposure, persisting severe PTSD symptoms were associated with worse family relationships, more smoking, less life satisfaction and happiness, more mental health service use, and more nonspecific health complaints at the 14‐year follow‐up. Further investigation is needed to determine whether the PTSD‐functioning relationship is causal and if successful treatment of PTSD is associated with improvement in functioning.
Deployment stressors and posttraumatic stress symptomatology: Comparing active duty and National Guard/Reserve personnel from Gulf War I
Authors: Vogt Dawne S. , Samper Rita E. , King Daniel W. , King Lynda A. , Martin James A. 
Published: February 2008

AbstractThe increased use of National Guard and Reserve (NG/R) military personnel in current conflicts raises the question of whether deployment experiences and their associations with posttraumatic stress symptomatology differ for active duty and NG/R military personnel. To date, very few studies are available on this topic. Moreover, it is unclear whether the impact of military status differs for women and men. We addressed these research issues in a sample of 311 female and male Gulf War I veterans. Several differences were observed in deployment stressor exposures and results based on differential associations generally suggested more negative impacts of deployment experiences for active duty women and NG/R men. The potential role of unit cohesion in explaining these findings is discussed.
Changes in psychiatric status and service use associated with continued compensation seeking after claim determinations for posttraumatic stress disorder
Authors: Sayer Nina A. , Spoont Michele , Nelson David B. , Clothier Barb , Murdoch Maureen 
Published: February 2008

AbstractThis study examined changes in psychiatric status and use of VA mental health services after the adjudication of Department of Veterans Affairs (VA) disability claims for posttraumatic stress disorder (PTSD) in a sample of 101 veteran claimants. Hypotheses were based on the premise that the claims process may create incentives for veterans to demonstrate illness. After the PTSD claim determination, half the sample had filed or planned to file a claim for a rating increase or an appeal and thus remained compensation seeking. Contradicting the authors' hypotheses, psychiatric status did not improve and treatment drop‐out rates did not increase among veterans who were no longer compensation seeking after the claim determination. Results have implications for the design and direction of future research.
Acute stress symptoms during the second Lebanon war in a random sample of Israeli citizens
Authors: Cohen Miri , Yahav Rivka 
Published: February 2008

AbstractThe aims of this study were to assess prevalence of acute stress disorder (ASD) and acute stress symptoms (ASS) in Israel during the second Lebanon war. A telephone survey was conducted in July 2006 of a random sample of 235 residents of northern Israel, who were subjected to missile attacks, and of central Israel, who were not subjected to missile attacks. Results indicate that ASS scores were higher in the northern respondents; 6.8% of the northern sample and 3.9% of the central sample met ASD criteria. Appearance of each symptom ranged from 15.4% for dissociative to 88.4% for reexperiencing, with significant differences between northern and central respondents only for reexperiencing and arousal. A low ASD rate and a moderate difference between areas subjected and not subjected to attack were found.
Flow of a non‐linear (density‐gradient‐dependent) viscous fluid with heat generation, viscous dissipation and radiation
Authors: Massoudi Mehrdad , Phuoc Tran X. 
Published: February 2008

AbstractIn this paper, we study the flow of a compressible (density‐gradient‐dependent) non‐linear fluid down an inclined plane, subject to radiation boundary condition. The convective heat transfer is also considered where a source term, similar to the Arrhenius type reaction, is included. The non‐dimensional forms of the equations are solved numerically and the competing effects of conduction, dissipation, heat generation and radiation are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Removing undersampling artifacts in DCE‐MRI studies using independent components analysis
Authors: Martel A.L. , Chan R.W. , Ramsay E. , Plewes D.B. 
Published: February 2008

AbstractIn breast MRI mammography both high temporal resolution and high spatial resolution have been shown to be important in improving specificity. Adaptive methods such as projection reconstruction time‐resolved imaging of contrast kinetics (PR‐TRICKS) allow images to be reconstructed at various temporal and spatial resolutions from the same data set. The main disadvantage is that the undersampling, which is necessary to produce high temporal resolution images, leads to the presence of streak artifacts in the images. We present a novel method of removing these artifacts using independent components analysis (ICA) and demonstrate that this results in a significant improvement in image quality for both simulation studies and for patient dynamic contrast‐enhanced (DCE)‐MRI images. We also investigate the effect of artifacts on two quantitative measures of contrast enhancement. Using simulation studies we demonstrate that streak artifacts lead to pronounced periodic oscillations in pixel concentration curves which, in turn, lead to increased errors and introduce bias into heuristic measurements. ICA filtering significantly reduces this bias and improves accuracy. Pharmacokinetic modeling was more robust and there was no evidence of bias due to the presence of streak artifacts. ICA filtering did not significantly reduce the errors in the estimated pharmacokinetic parameters; however, the chi‐squared error was greatly reduced after ICA filtering. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Implementation of a physical activity intervention for people with rheumatoid arthritis: A case study
Authors: van den Berg M.H. , van der Giesen F.J. , van Zeben D. , van Groenendael J.H.L.M. , Seys P.E.H. , Vliet Vlieland T.P.M. 
Published: February 2008

AbstractObjectives: To investigate the potential facilitators and barriers regarding the implementation on a larger scale of an internet‐based physical activity intervention which had previously proved to be effective in a randomized, controlled trial concerning sedentary patients with rheumatoid arthritis (RA).Methods: Assuming a central delivery of the intervention by two trained physical therapists in four regions in the Netherlands, the following activities were employed: the recruitment of potential participants (RA patients), the acquisition of cooperation from referring rheumatologists and the acquisition of reimbursement from regional health insurance companies. Evaluation was done by means of the Reach, Evaluation, Adoption, Implementation and Maintenance framework, of which the following three dimensions were considered relevant: Reach (the number of potential participants), Adoption (readiness for adopting the programme in real life among rheumatologists) and Implementation (the extent to which the intervention could be delivered as intended). Evaluation measures comprised a postal survey among 927 patients with RA in two regions, a telephone survey among rheumatology centres in four regions and consultations with five regional health insurance companies.Results: Seventy‐six out of 461 responding RA patients (20%) met the original study inclusion criteria (being sedentary and having access to the internet) and were interested in participation. However, the potential costs of the purchase of a bicycle ergometer and the interference with patients' current physical therapy were obstacles for eligible patients actually to participate. Rheumatologists in four out of five rheumatology centres were willing to participate. All five health insurance companies were willing to reimburse the guidance and feedback by the physical therapist, and the costs of the internet site (estimated costs €271 [£203] per patient per year), but not the bicycle ergometer (estimated costs €350 [£262]), provided that current physical therapy would be discontinued.Conclusions: Facilitators for the implementation of an internet‐based physical activity intervention were: (i) a considerable proportion of RA patients were eligible and interested in the programme; (ii) the majority of rheumatologists were willing to refer patients; and (iii) health insurance companies were willing partially to reimburse the intervention. Barriers were the additional costs for patients and their unwillingness to discontinue current physical therapy. These findings underscore the need for additional research into barriers to participation in physical activity interventions among patients with RA, and in reimbursement strategies in particular. Copyright © 2008 John Wiley & Sons, Ltd.
Radiofrequency coils for magnetic resonance microscopy
Authors: Neuberger Thomas , Webb Andrew 
Published: February 2008

AbstractGiven the several orders of magnitude fewer spins per voxel for MR microscopy than for conventional MRI, efficient coil design is important to obtain sufficient signal‐to‐noise within reasonable data acquisition times. As MR microscopy is typically performed using very high magnetic fields, coil design must also incorporate the effects of increased component losses and skin‐depth‐dependent resistance, as well as radiation losses and phase effects for coils when conductor dimensions constitute a substantial fraction of the electromagnetic wavelength. For samples much less than 1 mm in size, wire solenoids or microfabricated planar coils are used. For samples with diameters of several millimeters, saddle, birdcage, Alderman–Grant or millipede coils become the preferred choice. Recent advances in multiple‐coil probes and phased arrays have been used to reduce data acquisition time and/or increase sample throughput, and small superconducting coils have shown significant improvements in signal‐to‐noise over equivalently sized room‐temperature coils. Copyright © 2008 John Wiley & Sons, Ltd.