13C and 19F solid-state NMR and X-ray crystallographic study of halogen-bonded frameworks featuring nitrogen-containing heterocycles.

Halogen bonding is a noncovalent interaction between the electrophilic region of a halogen (σ-hole) and an electron donor. We report a crystallographic and structural analysis of halogen-bonded compounds by applying a combined X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (SSNMR) approach. Single-crystal XRD was first used to characterize the halogen-bonded cocrystals formed between two fluorinated halogen-bond donors (1,4-diiodotetrafluorobenzene and 1,3,5-trifluoro-2,4,6-triiodobenzene) and several nitrogen-containing heterocycles (acridine, 1,10-phenanthroline, 2,3,5,6-tetramethylpyrazine, and hexamethylenetetramine). New structures are reported for the following three cocrystals, all in the P21/c space group: acridine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C13H9N, 1,10-phenanthroline-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C12H8N2, and 2,3,5,6-tetramethylpyrazine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C8H12N2. 13C and 19F solid-state magic-angle spinning (MAS) NMR is shown to be a convenient method to characterize the structural features of the halogen-bond donor and acceptor, with chemical shifts attributable to cocrystal formation observed in the spectra of both nuclides. Cross polarization (CP) from 19F to 13C results in improved spectral sensitivity in characterizing the perfluorinated halogen-bond donor when compared to conventional 1H CP. Gauge-including projector-augmented wave density functional theory (GIPAW DFT) calculations of magnetic shielding constants, along with optimization of the XRD structures, provide a final set of structures in best agreement with the experimental 13C and 19F chemical shifts. Data for carbons bonded to iodine remain outliers due to well-known relativistic effects.

Managing migraine: strategies for successful patient outcomes.

This article highlights information from the 2000 National Conference for Nurse Practitioners symposium held in Washington, D.C., on November 9, 2000. It was sponsored by The Nursing Institute of Springhouse Corporation and funded by an unrestricted educational grant from Merck & Co., Inc. The firsttopic, "Overview of Migraine: Compelling Effects on Patients and Society," was presented for Dedie Downey Russell, CNP, ANP/GNP, MS. The second topic, "Understanding Pathophysiology: Evolving from Traditional to Current Therapeutic Options," was presented by Dara G. Jamieson, MD. Maureen Moriarty-Sheehan, MS, CRNP, who also served as chairperson, presented the third topic, "Developing a Management Plan for Optimal Patient Benefit."

Baseline data on the delivery of clinical preventive services provided by nurse practitioners.

The National Alliance of Nurse Practitioners (NANP) was one of five primary care provider groups that participated in a national government-sponsored survey on clinical preventive services (CPSs). The survey was based on 17 of the Healthy People 2000 national health objectives related to CPSs. This survey was sent to 2000 randomly selected nurse practitioners (NPs) to obtain information concerning the percentage of their patients who "routinely" receive the specified assessment and intervention services. Data from 892 completed and returned survey instruments indicated that NPs already exceed the Healthy People 2000 objective targets in some important clinical preventive assessment and intervention areas. They are close to the targets in a number of other CPS areas. In some areas, however, NP provision of preventive services was reported to be below the Healthy People 2000 targets. This data has far-reaching implications for NP practice, basic and continuing education, and curriculum reform.

Young northern pike, yellow perch and crayfish as bioindicators in a mercury contaminated watercourse.

Young-of-the-year and yearling northern pike (Esox lucius), yearling yellow perch (Perca flavescens) and adult crayfish (Orconectes virilis) were collected in the mercury-contaminated Wabigoon/English/Winnipeg River System, Ontario, and analyzed for total mercury. Analysis of mercury concentrations in these organisms produced consistent geographical trends; i.e. mercury concentrations in biota downstream of Dryden > English River system > Winnipeg River system > control sites. In the Wabigoon River system the bioavailability of mercury increases with distance downstream of the historical point source. Mercury concentrations in the biota studied were highly correlated with mercury concentrations in fish species which are of sport and commercial interest. The locations where young fish obtain their bodyburdens are known typically within 100 m. The biota studied compare favourably with the criteria proposed by Phillips (1980) as prerequisites for biological indicators. The wide distribution of young pike, perch and crayfish in North America, Europe and Asia may enhance their appeal as biomonitors.

Multicompetency education in radiologic technology.

A primary method of cost control in health care facilities is the utilization of one employee in more than one capacity. The need for multicompetency education is readily apparent in radiologic technology, a field that consists of a wide variety of closely related specialty areas. The curriculum in the Division of Radiological Health Sciences at the University of Texas School of Allied Health Sciences at Galveston, has been specifically structured to accommodate this need. The division offers associate degree programs in radiography, nuclear medicine technology, and radiation therapy technology, and makes use of a core curriculum. The division also offers advanced skills training in subspecialty areas at the postassociate level in computed tomography, magnetic resonance imaging, angiography, and dosimetry. An evaluation of this system of multicompetent education is provided, based on a survey of graduates from the program. Multicompetent graduates were found to receive significantly higher salaries, enjoy an expanded job market, and have consistently better outlooks toward their future careers than single-skilled graduates.