Design and fabrication of robust broadband extreme ultraviolet multilayers

The random layer thickness variations can induce a great deformation of the experimental reflection of broadband extreme ultraviolet multilayer. In order to reduce this influence of random layer thickness fluctuations, the multiobjective genetic algorithm has been improved and used in the robust design of multilayer with a broad angular bandpass. The robust multilayer with a lower sensitivity to random thickness errors have been obtained and the corresponding multilayer mirrors were fabricated. The experimental results of robust Mo/Si multilayer with a wide angular band were presented and analyzed, and the advantage of robust multilayer design was demonstrated

The unique rapid variabilities of the iron Kα\alpha line profiles in NGC 4151

We present a detailed analysis of the iron K$\alpha$ line variabilities in NGC 4151 by using long ASCA observation data obtained in May 1995. Despite the relatively small amplitude variations in the continuum flux, the iron K$\alpha$ line flux and profile show dramatic variations. Particularly, the line profile changes from single peak to seeming double peaks and back in time scales of a few 10$^4$ sec. The seemingly double-peaked profiles can be well interpreted as line emission from a Keplerian ring around a massive black hole. An absorption line at around 5.9 keV is also marginnaly detected. We discussed current Fe K line models, but none of them can well explain the observed line and continuum variations.Comment: 18 pages, latex, 3 figures, ApJ accepte

Evaluation of POSSUM scoring system in the treatment of osteoporotic fracture of the hip in elder patients

ObjectiveTo evaluate the applicability of the modified physiological and operative severity score for enumeration of mortality and morbidity (POSSUM) scoring system in predicting mortality in the patients undergoing hip joint arthroplasty.MethodsA total of 295 patients with hip fractures were analyzed using the modified POSSUM surgical scoring system. The mean ages of the patients were 66.59 years in the complicative group, 62.28 years in noncomplicative group, 77.89 years in the death group and 63.25 years in the living group, respectively. The comparisons between the observed and predicted morbidity, between the observed and predicted mortality were made within 30 days after operation.ResultsThe average physiological scores and operative severity scores was 18.96 ± 4.83 and 13.47 ± 2.01 in complicative group, while 15.65 ± 3.66 and 11.74 ± 2.26 in noncomplicative group (P<0.05). The average physiological scores and operative severity scores was 25.56 ± 3.78 and 14.22 ± 0.67 in death group, while 16.46 ± 4.09 and 12.25 ± 2.33 in living group (P<0.05). Though POSSUM scoring system over-predicted the overall risk of death, its estimate was very close in the high risk groups (>10%). There was perfect consistence between the observed and the predicted morbidity as calculated by published predictor equation for morbidity, and consistence for mortality in the high risk band.ConclusionsModified POSSUM scoring system may be used to predict the morbidity in patients with hip fracture. Furthermore, POSSUM scoring system overpredicts the overall risk of death, but its estimate is close to the actual data in the high risk band (>10%)

Evidence for a population of beamed radio intermediate quasars

Whether radio intermediate quasars possess relativistic jets as radio-loud quasars is an important issue in the understanding of the origin of radio emission in quasars. In this letter, using the two-epoch radio data obtained during Faint Image of Radio Sky at Twenty centimeter sky (FIRST) and NOAO VLA Sky Survey (NVSS), we identify 89 radio variable sources in the Sloan Digital Sky Survey. Among them, more than half are radio intermediate quasars (RL=f2cm/f2500A<250). For all objects with available multiple band radio observations, the radio spectra are either flat or inverted. The brightness temperature inferred from the variability is larger than the synchrotron-self Compton limit for a stationary source in 87 objects, indicating of relativistic beaming. Considering the sample selection and viewing angle effect, we conclude that relativistic jets probably exist in a substantianl fraction of radio intermediate quasars.Comment: 15 pages, 4 figures, 1 table, Accepted to the Astrophysical Journa