Diagnostic accuracy of a clinical diagnosis of idiopathic pulmonary fibrosis: An international case-cohort study

We conducted an international study of idiopathic pulmonary fibrosis (IPF) diagnosis among a large group of physicians and compared their diagnostic performance to a panel of IPF experts. A total of 1141 respiratory physicians and 34 IPF experts participated. Participants evaluated 60 cases of interstitial lung disease (ILD) without interdisciplinary consultation. Diagnostic agreement was measured using the weighted kappa coefficient (\u3baw). Prognostic discrimination between IPF and other ILDs was used to validate diagnostic accuracy for first-choice diagnoses of IPF and were compared using the Cindex. A total of 404 physicians completed the study. Agreement for IPF diagnosis was higher among expert physicians (\u3baw=0.65, IQR 0.53-0.72, p20 years of experience (C-index=0.72, IQR 0.0-0.73, p=0.229) and non-university hospital physicians with more than 20 years of experience, attending weekly MDT meetings (C-index=0.72, IQR 0.70-0.72, p=0.052), did not differ significantly (p=0.229 and p=0.052 respectively) from the expert panel (C-index=0.74 IQR 0.72-0.75). Experienced respiratory physicians at university-based institutions diagnose IPF with similar prognostic accuracy to IPF experts. Regular MDT meeting attendance improves the prognostic accuracy of experienced non-university practitioners to levels achieved by IPF experts

Nevoid basal cell carcinoma syndrome (Gorlin syndrome)

Nevoid basal cell carcinoma syndrome (NBCCS), also known as Gorlin syndrome, is a hereditary condition characterized by a wide range of developmental abnormalities and a predisposition to neoplasms

Numerical analysis of an H4A heavy containment level transition

It is fact that European highway safety personnel are not aware of the significance of transition barriers. As a result, most countries do not use transition designs on their highways. On the other hand, the ones that are currently in use lack adequate detailing and do not provide the required level of protection during a collision event. In this paper, the impact performance of a standard US flared-back guardrail-to-bridge rail transition is evaluated using a 30,000 kg heavy goods vehicle according to European EN1317 test TB71 requirements. A highly acceptable and versatile non-linear finite element code, LS-DYNA, is used for the analysis. Simulation results show that the transition fails to contain the vehicle. The vehicle overrides the transition due to insufficient rail height. To upgrade the impact performance of the transition to H4a, high containment level, an additional rail element was added to the current design to increase the rail height from 810 mm to 1050 mm. Subsequent simulation results show that the modified transition design meets the EN1317 test TB71 requirements. It is therefore recommended that the current US standard flared back guardrail-to-bridge rail transition design should have a minimum of 1050 mm rail height to satisfy European crash testing guidelines for H4a, heavy containment level transition

Design and validation of A 30,000 kg heavy goods vehicle using LS-DYNA

Memoria con refere

Development of a Draft Heavy Vehicle Rear Underride Guard Specification

This paper summarizes results of a large research program intended to develop a draft rear underride guard specification for heavy vehicles. Results of a series of laboratory and full-scale crash tests performed at the Transport Canada Research Center were used in the development of these specifications. A total of eleven full-scale crash tests was carried out to evaluate the effectiveness of different underride guards. The first ten of these tests were performed on a simulated trailer attached guard. Four different underride guard designs were used in these ten full-scale crash tests. Three different vehicle models traveling at 48, 56 and 65 km/h speeds were used to impact underride guards head on. Results of the first ten crash tests show that the currently used US FMVSS 223 standard is far from adequate in preventing the occurrance of rear underride. Based on findings obtained from these crash tests, an improved guard design was developed and tested using a 16-meter trailer. This final crash test verified the effectiveness of improved guard design in reducing the undesirable effects of rear underride crashes. Based on the results, a draft heavy vehicle rear underride guard specification was developed

Evaluation of vertical wall-to-guardrail transition

Transition barriers are used to connect longitudinal barriers that have different stiffnesses. They are designed to provide a gradual increase in stiffness towards the stiffer barrier section. In this study, a W-beam rail and a W-beam rubrail transition connecting a rigid bridge rail to a semi-rigid guardrail was evaluated using numerical and experimental methods. First, a finite element model of the transition design was constructed and validated using a 2000 kg pickup truck impact. Then, a series of vehicle models, i.e., 900 kg compact automobile, 8000 kg single unit truck and finally 30,000 kg heavy truck was used to evaluate the impact performance of the same transition design numerically. Simulation results predict that the double W-beam transition barrier performs acceptably in containing and redirecting all vehicles except 30,000 kg heavy truck. Occupant injury criteria were also found to be acceptable for all the cases, except 30,000 kg truck impact. Performing further simulations with vehicle sizes heavier than 8,000 kg that exist in crash testing guidelines is recommended to evaluate the acceptability limit of existing W-beam rail and a W-beam rubrail transition

presence of hyperoxaluria

Hyperoxaluria is a well-known cause of renal stone disease and in vitro studies have shown that oxalate crystals have a stimulatory effect on apoptosis of renal tubular epithelial cells. Total and partial ureteral obstruction also have an accelerating effect on apoptosis of renal tubular epithelial cells. The aim of the present study was to investigate the apoptotic effect of unilateral ureteral obstruction in the presence of hyperoxaluria on the rat kidney. Twenty-eight male Wistar rats were divided into four groups, with seven rats in each. The groups were named G1 (control), G2 (hyperoxaluric), G3 (obstructive) and G4(hyperoxaluric + obstructive). G2 and G4 rats were given 1% ethylene glycol (a precursor for oxalates) in their drinking water. G1 and G2 rats underwent sham operation, while left proximal ureteral ligation with a 5-zero silk suture was performed on G3 and G4 animals. The rats were sacrificed 2 weeks after the operation; left nephrectomy was then performed. We searched for the apoptotic cells by direct immuno-peroxidase detection of digoxigenin-labeled genomic DNA. The mean +/- SD values of the apoptotic cell count was 0.86 +/- 0.90 in G1 and 4.33 +/- 3.81 in G2. The values for G3 and G4 were 30.17 +/- 16.85 and 302.67 +/- 184.45, respectively. We found a statistically significant difference between all groups (P < 0.001). When compared with the control group (G1), the mean apoptotic cell count was fivefold that of G2 and 35- and 351-fold those of G3 and G4, respectively. Our study demonstrated that hyperoxaluria with complete ureteral obstruction induces an excessive level of apoptosis, which is responsible for renal damage, and that ureteral obstruction is a more important factor for apoptosis than hyperoxaluria. Considering these data, we also believe that research studies for medical preventive measures must be considered for patients with ureteral obstruction and/or hyperoxaluria