Measurement of angular distribution of soft X-ray radiation from thin targets in the tabletop storage ring MIRRORCLE-20SX.

The only available tabletop electron storage rings are the machines from the MIRRORCLE series. The electrons are accelerated in a microtron and injected into the storage ring. During its circulation, each electron passes through a tiny target many times, emitting a photon beam. Both the spectrum and the angular distribution of the radiation depend on the material, the thickness and the shape of the target. In this paper measured angular distributions of the radiation from several different targets in the magnetic field of the 20 MeV storage ring MIRRORCLE-20SX are presented. The detector comprises a 3 mm × 3 mm × 8.5 µm plastic scintillator (PS) coupled to a photomultiplier by a bundle of optical fibers. The output of the photomultiplier is digitized by an IF converter. This detector is sensitive mostly to soft X-ray radiation, and its PS is moved by a mechanical system in a plane perpendicular to the radiation axis. The measured angular distributions for Mo and Sn targets contain an annulus which is attributed to transition radiation. The angular distributions for Al, carbon nanotube and diamond-like carbon (DLC) targets show some suppression of the radiation along the magnetic field. This is the first evidence of observation of the angular distribution of synchrotron Cherenkov radiation, which represents Cherenkov radiation in a magnetic field. The power radiated from the DLC target is estimated.

A prospective study assessing patient satisfaction at a large tertiary gynecologic oncology/dysplasia unit.

BACKGROUND: Patient satisfaction is an important quality assurance measure in the delivery of health care. We conducted a prospective study to assess patient satisfaction at a large tertiary oncology/dysplasia unit. AIMS: To assess current patient satisfaction at a large tertiary oncology/dysplasia unit and identify potential areas for improvement. METHODS: This was a prospective study of patients attending a tertiary oncology/dysplasia unit. Patients were invited to participate and, if they agreed, were given a validated questionnaire to complete at the end of their consultation. Descriptive statistics were then used to analyze the data and identify potential areas of improvement. RESULTS: One hundred eighty-seven patients were recruited, and 96% of patients were satisfied with the overall level of care received. Significant positive features of the service included helpfulness of the staff, cleanliness of the facility, and measures implemented to respect patient privacy. Lack of patient parking, waiting times in the clinic, difficulties in contacting the service, and locating the building were identified as areas for improvement. CONCLUSION: Patients attending our facility were largely satisfied with the overall level of care received. Nonclinical factors including parking, waiting times, and access to the service were identified as areas for improvement.

Strong, transparent, multifunctional, carbon nanotube sheets.

Individual carbon nanotubes are like minute bits of string, and many trillions of these invisible strings must be assembled to make useful macroscopic articles. We demonstrated such assembly at rates above 7 meters per minute by cooperatively rotating carbon nanotubes in vertically oriented nanotube arrays (forests) and made 5-centimeter-wide, meter-long transparent sheets. These self-supporting nanotube sheets are initially formed as a highly anisotropic electronically conducting aerogel that can be densified into strong sheets that are as thin as 50 nanometers. The measured gravimetric strength of orthogonally oriented sheet arrays exceeds that of sheets of high-strength steel. These nanotube sheets have been used in laboratory demonstrations for the microwave bonding of plastics and for making transparent, highly elastomeric electrodes; planar sources of polarized broad-band radiation; conducting appliqués; and flexible organic light-emitting diodes.

Multifunctional carbon nanotube yarns by downsizing an ancient technology.

By introducing twist during spinning of multiwalled carbon nanotubes from nanotube forests to make multi-ply, torque-stabilized yarns, we achieve yarn strengths greater than 460 megapascals. These yarns deform hysteretically over large strain ranges, reversibly providing up to 48% energy damping, and are nearly as tough as fibers used for bulletproof vests. Unlike ordinary fibers and yarns, these nanotube yarns are not degraded in strength by overhand knotting. They also retain their strength and flexibility after heating in air at 450 degrees C for an hour or when immersed in liquid nitrogen. High creep resistance and high electrical conductivity are observed and are retained after polymer infiltration, which substantially increases yarn strength.