Productivity in construction : an issue of analysis and measurement

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1988.Includes bibliographical references.by Nicholas Stathakis.M.S

Photometric and Spectroscopic Observations of SN 1990E in NGC 1035: Observational Constraints for Models of Type II Supernovae

We present 126 photometric and 30 spectral observation of SN 1990E spanning from 12 days before B maximum to 600 days past discovery. These observations show that SN 1990E was of type II-P, displaying hydrogen in its spectrum, and the characteristic plateau in its light curve. SN 1990E is one of the few SNe II which has been well observed before maximum light, and we present evidence that this SN was discovered very soon after its explosion. In the earliest spectra we identify, for the first time, several N II lines. We present a new technique for measuring extinction to SNe II based on the evolution of absorption lines, and use this method to estimate the extinction to SN 1990E, Av=1.5+/-0.3 mag. From our photometric data we have constructed a bolometric light curve for SN 1990E and show that, even at the earliest times, the bolometric luminosity was falling rapidly. We use the late-time bolometric light curve to show that SN 1990E trapped a majority of the gamma rays produced by the radioactive decay of 56Co, and estimate that SN 1990E ejected 0.073 Mo of 56Ni, an amount virtually identical to that of SN 1987A. [excerpt

Body pain during daily activities in patients on peritoneal dialysis

Objective. To review the prevalence of body pain during daily activities in patients on peritoneal dialysis (PD) and to correlate it with various demographic and renal osteodystrophy markers such as calcium (Ca), phosphorus (P), intact parathyroid hormone (iPTH), and vitamin D-3 levels. Methods. A cross-sectional study was conducted involving 530 chronic PD patients (44.3 % female, 55.6 % male) from 24 centers in Canada, Greece, and Turkey. Pain severity scoring during daily activities was performed using the pain scoring table of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Results. The overall prevalence of pain was 52.9 % (61.3 % in females and 49.5 % in males, p 0.05). Mean serum 25-hydroxyvitamin D-3 [25(OH)D-3] levels were lower in patients with pain compared to those without pain (p < 0.05). Conclusions. A high percentage of the PD patients (53 %) had body pain; iPTH levels and other biochemical parameters of renal osteodystrophy were not different between those with and without pain. Patients with pain had lower 25(OH)D-3 levels than did those without. Factors such as age, gender, obesity, and metabolic factors may interact to cause varying degrees of articular/bone pain in patients on PD. Since vitamin D deficiency aggravates the signs and symptoms of joint disease such as pain and stiffness, one should attempt to correct levels of 25(OH)D-3, as well as 1,25(OH)(2)D-3 levels, in these patients