Room-temperature metal-hydride discharge source, with observations on NiH and FeH.

A metal sputtering source suitable for laboratory production of metal hydrides is described. Sputtering from pure nickel or iron in an Ar/H(2) discharge is analyzed at low resolution. High resolution laser excitation and dispersed fluorescence spectra of NiH have also been recorded. The source has been designed to operate with a ferromagnetic circuit for Zeeman spectroscopy. Signals from the source are strong enough to record dispersed fluorescence from NiH by Fourier transform interferometry in magnetic fields up to 1 T. We establish that FeH can also be formed in this source.

Terahertz vibration-rotation-tunneling spectroscopy of the water tetramer-d8: combined analysis of vibrational bands at 4.1 and 2.0 THz.

We report the measurement of terahertz vibration-rotation-tunneling spectra of (D(2)O)(4) in the spectral region near 4.13 THz. The characterization of this perpendicular band extends a previously reported study [J. Chem. Phys. 111, 7801 (1999)]. We observed 239 new transitions, each being split into a doublet of constant (approximately 192 MHz) spacing. These are included in a combined fit with the 113 previously measured transitions of the 2.03 THz parallel band using an effective Hamiltonian similar to that used in the global fit of the water trimer. The detailed understanding of the water tetramer evolving from this work underlies our efforts to quantify the contribution of many-body forces to the hydrogen bonding interactions in condensed phase water.

Water pentamer: characterization of the torsional-puckering manifold by terahertz VRT spectroscopy.

We present the measurement and analysis of five new (D2O)5 bands via vibration-rotation-tunneling (VRT) spectroscopy as well as a preliminary description of a second (H2O)5 band. The vibrationally averaged rotational constants of all five fitted bands agree well with those from the two previously observed (D2O)5 bands and confirm that the pentamer averages to a symmetric, quasi-planar structure on the time scale of our experiment. While the spectrum of the first two bands, located at 50.7 cm(-1) (1.52 THz) and 27.3 cm(-1) (0.82 THz) are indicative of unperturbed oblate rotors, the three remaining (D2O)5 bands centered at 47.7 cm(-1) (1.43 THz), 45.4 cm(-1) (1.36 THz), and 45.0 cm(-1) (1.35 THz) are severely perturbed by first-order Coriolis coupling. This represents the first observation of this perturbation in the perdeuterated water pentamer, as well as the first observation of transitions between degenerate states of the torsional-puckering manifold. Unlike transitions from the (H2O)5 band observed by Brown et al. at 89.0 cm(-1) and the 103.8 cm(-1) band that we report here, none of the individual rovibrational transitions of any of the five (D2O)5 bands demonstrate spectral splittings due to bifurcation tunneling. We conclude, through careful analysis of these water pentamer bands, that at least three torsional-puckering manifolds have been probed and that the lowest-energy manifold is highly compacted. A plausible water pentamer torsional-puckering correlation diagram is proposed, though additional experimental data are required to unambiguously establish the energies of the torsional-puckering levels.

Communicating about health care: observations from persons who are deaf or hard of hearing.

BACKGROUND: Achieving patient-centered care requires effective communication between physicians and patients. Persons who are deaf or hard of hearing face considerable barriers to communicating with physicians. OBJECTIVE: To understand perceptions of health care experiences and suggestions for improving care among deaf or hard-of-hearing individuals. DESIGN: 4 semistructured group interviews, 2 conducted in American Sign Language (for deaf individuals) and 2 using Communication Access Realtime Translation (for hard-of-hearing individuals). Men and women were interviewed separately. Tapes of interviews were transcribed verbatim for analysis. SETTING: Greater Boston, Massachusetts, and Washington, DC, in 2001. PARTICIPANTS: 14 deaf adults (23 to 51 years of age) and 12 hard-of-hearing adults (30 to 74 years of age). MEASUREMENTS: Commonly expressed themes or views organized around dimensions of communication. RESULTS: Concerns coalesced around 6 broad themes: conflicting views between physicians and patients about being deaf or hard of hearing; different perceptions about what constitutes effective communication (such as lip reading, writing notes, and sign language interpreter); medication safety and other risks posed by inadequate communication; communication problems during physical examinations and procedures; difficulties interacting with office staff, including in waiting rooms; and problems with telephone communication, such as lengthy message menus. Participants offered extensive suggestions for improvements, starting with clinicians' asking patients about their preferred communication approach. Having patients repeat critical health information (such as medication instructions) can identify potentially dangerous miscommunication. CONCLUSIONS: As the population ages, physicians will encounter many more persons with hearing limitations. Physicians are not reimbursed for making some accommodations, such as hiring sign language interpreters. However, ensuring effective communication is essential to safe, timely, efficient, and patient-centered care.