Analysis Of Radiographic Data Research Articles

Measurement of mix at the fuel–ablator interface in indirectly driven capsule implosions on the National Ignition Facility

The interface between the capsule ablator and fuel ice layer is susceptible to hydrodynamic instabilities. The subsequent mixing of hot ablator material into the ice reduces fuel compression at stagnation and is a candidate for reduced capsule performance. The ability to diagnose ice–ablator mix is critical to understanding and improving stability at this interface. Combining the crystal backlighter imager with the single line of sight camera on the National Ignition Facility (NIF) allows direct measurement of ice–ablator mix by providing multiple quasi-monochromatic radiographs of layered capsule implosions per experiment with high spatial (∼12 μm) and temporal (∼35 ps) resolution. The narrow bandwidth of this diagnostic platform allows radiography of the inner edge of the capsule limb close to stagnation without capsule self-emission contaminating the data and removes opacity uncertainties typically associated with the spectral content of the radiograph. Analysis of radiographic data via a parameterized forward-fitting Abel inversion technique provides measurements of the distribution of mix mass inwards from the ice–ablator interface. The sensitivity of this mix measurement technique was demonstrated by applying it to layered experiments in which the stability of the ice–ablator interface was expected to vary significantly. Additional experiments suggest that high-density carbon capsules that employ a buried-layer dopant profile suffer from mixing at the innermost doped–undoped interface. Data from these experiments suggest that opacity models used in hydrodynamic simulations of NIF experiments can potentially over-predict the opacity of doped capsules. LLNL-JRNL-850535-DRAFT.

Sacral spinous processes: a morphologic classification and biomechanical characterization of strength

Sacral spinous processes: a morphologic classification and biomechanical characterization of strength

Age-dependent ferritin elevations and HFE C282Y mutation as risk factors for symptomatic knee osteoarthritis in males: a longitudinal cohort study

BackgroundAge, gender and genetic predisposition are major intrinsic risk factors for osteoarthritis (OA). Iron increases are associated with age and gene mutation. In the present study, we examined whether serum ferritin, an indicator of total body iron stores, correlates with clinical features in patients with OA, and whether the hemochromatosis Fe (HFE) gene mutation plays a role.MethodsIn a 2-year longitudinal observational study, 127 patients with knee OA and 20 healthy individuals (controls) were enrolled. All patients underwent standardized weight-bearing fixed-flexion posteroanterior knee radiographs. Peripheral blood samples were analyzed for serum ferritin, and genotyped for HFE using allelic discrimination methods.ResultsHigher levels of serum ferritin were found in patients older than 56 years (P =0.0186) and males (P =0.0006), with a trend toward higher ferritin in patients with OA. HFE gene mutation carriers were more prevalent among patients with OA than among healthy controls. When stratified further by gender, we found that male patients with OA had higher levels of serum ferritin than male control subjects [odds ratio = 4.18 (limits of 95% confidence interval: 0.86–27.69, P = 0.048)]. Analyses of radiographic data indicated that higher ferritin was associated with narrower joint space width at baseline (P = 0.032) in male patients. Additionally, among men, risk prediction of radiographic severity [Kellgren-Lawrence (KL) grade >2)] in the higher ferritin group was almost five times that of the lower ferritin group (odds ratio = 4.74, P = 0.023).ConclusionOur data suggest that increased ferritin levels are associated with symptomatic knee OA in males. This finding needs to be validated in a larger cohort of patients.

Osteoprogenitor Cell Therapy in an Equine Fracture Model

To compare the efficacy of osteoprogenitors in fibrin glue to fibrin glue alone in bone healing of surgically induced ostectomies of the fourth metacarpal bones in an equine model. Experimental. Adult horses (n = 10). Segmental ostectomies of the 4th metacarpal bone (MC4) were performed bilaterally in 10 horses. There was 1 treatment and 1 control limb in each horse. Bone defects were randomly injected with either fibrin glue and osteoprogenitor cells or fibrin glue alone. Radiography was performed every week until the study endpoint at 12 weeks. After euthanasia, bone healing was evaluated using radiography and histology. Analysis of radiographic data was conducted using a linear-mixed model. Analysis of histologic data was conducted using a general linear model. Statistical significance was set at P < .05. Radiographic grayscale data as a measure of bone healing revealed no significant difference between treatment and control limbs. Radiographic scoring results also showed that the treatment effect was not significant. Histologic analysis was consistent with radiographic analysis showing no significant difference between the area of bone present in treatment and control limbs. Injection of periosteal-derived osteoprogenitors in a fibrin glue carrier into surgically created ostectomies of MC4 does not accelerate bone healing when compared with fibrin glue alone.

Presentation and analysis of radiographic data in clinical trials and observational studies

Presentation and analysis of radiographic data in clinical trials and observational studies

Presentation and analysis of data on radiographic outcome in clinical trials: Experience from the TEMPO study

To evaluate different methods of presentation and analysis of radiographic data in a rheumatoid arthritis (RA) randomized controlled trial. A double-blind randomized controlled trial including 682 patients with active RA who were treated with methotrexate, etanercept, or a combination of the 2 drugs was used for this study. Probability plots of the change from baseline to year 1 were produced to visualize progression, and were compared with usual descriptive statistics. The primary analysis of the trial (based on annualized actual mean change from baseline in total Sharp score at 1 year, using linear imputation) was challenged using various ways of handling missing information with alternative imputation methods, and by various statistical analyses including analysis of covariance (ANCOVA) and mixed model analysis on both raw and log-transformed data. Probability plots provided detailed insight into the differentiated treatment effects between the 3 arms of this study. As adjuncts to formal hypothesis testing, these plots were more useful for presenting data than were summary descriptive statistics or use of preset cutoff points to define lack of progression. Additional analyses presented here support the results obtained with the per-protocol analysis that showed an advantage of the combination treatment compared with the monotherapy arms and for etanercept versus methotrexate alone. Various ways of handling missing information confirmed the robustness of the results. In addition, both ANCOVA and mixed model analyses on raw and on log-transformed data produced similar results. We suggest a panel of alternative analysis methods and alternative ways of handling missing information to verify that the radiographic results reported in an randomized controlled trial are not influenced by technical factors, such as interpolation, handling of missing data, and choice of statistical tests.

Non-surgical treatment of condylar fractures in adults: a retrospective analysis

Non-surgical treatment of condylar fractures in adults: a retrospective analysis

Effect of controlled reperfusion techniques in human lung transplantation

Effect of controlled reperfusion techniques in human lung transplantation

Recipient intramuscular gene transfer of naked plasmid TGFβ1 ameliorates lung graft reperfusion injury

Recipient intramuscular gene transfer of naked plasmid TGFβ1 ameliorates lung graft reperfusion injury

Fractures of the condyle and the condylar neck: Conservative versus operative treatment

Fractures of the condyle and the condylar neck: Conservative versus operative treatment

Mortality among workers in the diatomaceous earth industry.

A cohort mortality study was conducted among workers from two plants in the diatomaceous earth mining and processing industry in California. Diatomaceous earth consists of the skeletal remains of diatoms. Exposure to amorphous (non-crystalline) and crystalline silica in the form of quartz results from open pit mining and exposure to crystalline silica (principally cristobalite) occurs in the processing of the material. Lung cancer and non-malignant respiratory diseases have been the health outcomes of greatest concern. The main study cohort included 2570 white men (533 Hispanic and 2017 non-Hispanic workers) who were employed for at least 12 months cumulative service in the industry and who had worked for at least one day during the follow up period, 1942-87. Vital status was ascertained for 91% of the cohort and death certificate information was retrieved for 591 of 628 (94%) identified deaths. The all causes combined standardised mortality ratio (SMR) was slightly increased (SMR = 1.12; 628 observed) compared with rates among US white males. The principal contributors to this excess were increased risks from lung cancer (SMR = 1.43; 59 observed) and non-malignant respiratory disease (NMRD) excluding infectious diseases and pneumonia (SMR = 2.59; 56 observed). The excess of lung cancer persisted when local county rates were used for comparison (SMR = 1.59). Internal rate comparisons by Poisson regression analysis were conducted to assess potential dose-response relations for lung cancer and NMRDs. Mortality trends were examined in relation to duration of employment in dust exposed jobs and with respect to an index of cumulative exposure to crystalline silica. The crystalline silica index was a semiquantitative measure that combined information on duration of exposure, differences in exposure intensity between jobs and calendar periods, the crystalline content of the various product mixes, and the use of respiratory protection devices. Increasing gradients of risk were detected for lung cancer and NMRD with both exposure indices. The relative risk trends for lung cancer and NMRD with crystalline silica exposure lagged 15 years were respectively: 1.00, 1.19, 1.37, and 2.74, and 1.00, 1.13, 1.58, and 2.71. Based on a review of available but limited data on cigarette smoking in the cohort and from application of indirect methods for assessing confounding variables, it seems unlikely that smoking habits could account for all of the association between exposure to dust and lung cancer. The intense and poorly controlled dust exposures encountered before the 1950s were probably the most aetiologically significant contributors to risks from lung cancer and NMRDs. The absence of an excess of lung cancer among workers hired since 1960, and the finding of no deaths attributed to pneumoconiosis as an underlying cause of death among workers hired since 1950 indicate that exposure reductions in the industry during the past 40 years have been successful in reducing excess risks to workers. Further mortality follow up of the cohort and the analysis of radiographic data will be needed to determine conclusively the long term patterns of disease risks in this industry.