Advanced composites: Design and application. Proceedings of the meeting of the Mechanical Failures Prevention Group

The design and application of advanced composites is discussed with emphasis on aerospace, aircraft, automotive, marine, and industrial applications. Failure modes in advanced composites are also discussed

Detection, Diagnosis and Prognosis: Contribution to the energy challenge: Proceedings of the Meeting of the Mechanical Failures Prevention Group

The contribution of failure detection, diagnosis and prognosis to the energy challenge is discussed. Areas of special emphasis included energy management, techniques for failure detection in energy related systems, improved prognostic techniques for energy related systems and opportunities for detection, diagnosis and prognosis in the energy field

Innovation for maintenance technology improvements

A group of 34 submitted entries (32 papers and 2 abstracts) from the 33rd meeting of the Mechanical Failures Prevention Group whose subject was maintenance technology improvement through innovation. Areas of special emphasis included maintenance concepts, maintenance analysis systems, improved maintenance processes, innovative maintenance diagnostics and maintenance indicators, and technology improvements for power plant applications

Clinical effectiveness of Enneking appropriate versus Enneking inappropriate procedure in patients with primary osteosarcoma of the spine: a systematic review with meta-analysis

Purpose Primary osteosarcoma of the spine is a rare osseous tumour. En bloc resection, in contrast to intralesional resection, is the only procedure able to provide Enneking appropriate (EA) margins, which has improved local control and survival of patients with primary osteosarcoma of the spine. The objective of this study is to compare the risk of local recurrence, metastases development and survival in patients with primary osteosarcoma of the spine submitted to Enneking appropriate (EA) and Enneking inappropriate (EI) procedures. Methods A systematic search was performed on EBSCO, PubMed and Web of Science, between 1966 and 2018, to identify studies evaluating patients submitted to resection of primary osteosarcoma of the spine. Two reviewers independently assessed all reports. The outcomes were local recurrence, metastases development and survival at 12, 24 and 60 months. Results Five studies (108 patients) were included for systematic review. These studies support the conclusion that EA procedure has a lower local recurrence rate (RR 0.33, 95% CI 0.17-0.66), a lower metastases development rate (RR 0.39, 95% CI 0.17-0.89) and a higher survival rate at 24 months (RR 1.78, 95% CI 1.24-2.55) and 60 months (RR 1.97, 95% CI 1.14-3.42) of follow-up; however, at 12 months, there is a non-significant difference. Conclusions EA procedure increases the ratio of remission and survival after 24 months of follow-up. Multidisciplinary oncologic groups should weigh the morbidity of an en bloc resection, knowing that in the first year the probability of survival is the same for EA and EI procedures. Graphic abstract These slides can be retrieved under Electronic Supplementary Material

Prospective Evaluation of Single and Triple Lumen Catheters in Total Parenteral Nutrition

The recent introduction of triple lumen catheters has facilitated the care of seriously ill patients by providing multipurpose central venous access through a single percutaneous 7 French catheter. This prospective study was performed to examine the complications associated with the use of these catheters in patients receiving long-term total parenteral nutrition (TPN). Seventy-five patients undergoing catheterization were randomly separated into two groups: 36 patients underwent placement of a single lumen catheter (SLC), and 39 patients, a triple lumen catheter (TLC). The two groups were comparable with respect to concomitant infections, treatment with antibiotics, and need for intensive care. Patients in the SLC group received TPN for a mean of 9.7 days and in the TLC group, for a mean of 8.5 days (p = 0.427). However, after 5 days of catheterization, there was a marked increase in the number of TLC removed because of skin entry site infections. SLC were more likely to be used for the full duration of TPN administration (p = 0.025). Catheter tips were cultured by semiquantitative techniques. A higher incidence of catheter sepsis was seen with TLC, 12.8% vs 0% with SLC (p = 0.055). TLC used for TPN are associated with higher rates of catheter entry site infections and systemic sepsis. SLC should be used for TPN administration

Prospective Evaluation of Single and Triple Lumen Catheters in Total Parenteral Nutrition

The recent introduction of triple lumen catheters has facilitated the care of seriously ill patients by providing multipurpose central venous access through a single percutaneous 7 French catheter. This prospective study was performed to examine the complications associated with the use of these catheters in patients receiving long-term total parenteral nutrition (TPN). Seventy-five patients undergoing catheterization were randomly separated into two groups: 36 patients underwent placement of a single lumen catheter (SLC), and 39 patients, a triple lumen catheter (TLC). The two groups were comparable with respect to concomitant infections, treatment with antibiotics, and need for intensive care. Patients in the SLC group received TPN for a mean of 9.7 days and in the TLC group, for a mean of 8.5 days (p = 0.427). However, after 5 days of catheterization, there was a marked increase in the number of TLC removed because of skin entry site infections. SLC were more likely to be used for the full duration of TPN administration (p = 0.025). Catheter tips were cultured by semiquantitative techniques. A higher incidence of catheter sepsis was seen with TLC, 12.8% vs 0% with SLC (p = 0.055). TLC used for TPN are associated with higher rates of catheter entry site infections and systemic sepsis. SLC should be used for TPN administration

Two Stage Helical Gearbox Fault Detection and Diagnosis based on Continuous Wavelet Transformation of Time Synchronous Averaged Vibration Signals

Vibration signals from a gearbox are usually very noisy which makes it difficult to find reliable symptoms of a fault in a multistage gearbox. This paper explores the use of time synchronous average (TSA) to suppress the noise and Continue Wavelet Transformation (CWT) to enhance the non-stationary nature of fault signal for more accurate fault diagnosis. The results obtained in diagnosis an incipient gear breakage show that fault diagnosis results can be improved by using an appropriate wavelet. Moreover, a new scheme based on the level of wavelet coefficient amplitudes of baseline data alone, without faulty data samples, is suggested to select an optimal wavelet

The role of cavitation in mechanical failures; proceedings of the 19th meeting of the Mechanical Failures Prevention Group.

Papers presented at the meeting, held Oct. 31-Nov. 2, 1973, in Boulder, Colo.Includes bibliographical references.Mode of access: Internet

NBS Building Science Series, Bulletin 143

Report issued by the National Bureau of Standards documenting investigations conducted on construction failures of two suspended walkways in a Kansas City hotel. It includes tables, illustrations, photographs, and other details of the investigation