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1.
Int Nurs Rev ; 54(1): 92-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17305963

ABSTRACT

AIM: To determine the current level of job satisfaction among nurses in the Republic of Ireland. To identify the factors that make the greatest contribution to nurses' current level of job satisfaction. To establish the difference between (a) the factors that nurses regard as being important to their job satisfaction, and (b) those factors that actually contribute to nurses' current level of job satisfaction. To enter the findings into a database maintained by Market Street Research in the USA. BACKGROUND: A review of the literature suggests that (a) job satisfaction among nurses is low, and (b) job satisfaction research in nursing is growing. METHODS: This paper represents the descriptive findings of a study that used a mixed-method design. Data collection involved the use of a postal questionnaire survey and the sample was selected using stratified random sampling. FINDINGS: The findings confirmed low to moderate levels of job satisfaction among nurses. Factors such as professional status, interaction and autonomy made the greatest contribution to nurses' job satisfaction. CONCLUSION: Overall, the findings are consistent with those of previous research on nurses' job satisfaction. The implications are that health service administrators and nursing managers need to design and implement initiatives that will promote professional status, interaction and autonomy among nurses within their organizations and address the reasons why task requirements, organizational policies and pay make less of a contribution to the current level of job satisfaction.


Subject(s)
Job Satisfaction , Nurses/psychology , Data Collection , Ireland , Postal Service , Professional Autonomy , Salaries and Fringe Benefits
2.
Opt Lett ; 29(4): 397-9, 2004 Feb 15.
Article in English | MEDLINE | ID: mdl-14971765

ABSTRACT

A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in a dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 microm. The frequency comb was referenced simultaneously to the National Institute of Standards and Technology's optical frequency standard based on neutral calcium and to a hydrogen maser that is calibrated by a cesium atomic fountain clock. With this comb we measured two frequency references in the telecommunications band: one half of the frequency of the d/f crossover transition in 87Rb at 780 nm, and the methane v2 + 2v3 R(8) line at 1315 nm.

3.
Science ; 293(5531): 825-8, 2001 Aug 03.
Article in English | MEDLINE | ID: mdl-11452082

ABSTRACT

Microwave atomic clocks have been the de facto standards for precision time and frequency metrology over the past 50 years, finding widespread use in basic scientific studies, communications, and navigation. However, with its higher operating frequency, an atomic clock based on an optical transition can be much more stable. We demonstrate an all-optical atomic clock referenced to the 1.064-petahertz transition of a single trapped 199Hg+ ion. A clockwork based on a mode-locked femtosecond laser provides output pulses at a 1-gigahertz rate that are phase-coherently locked to the optical frequency. By comparison to a laser-cooled calcium optical standard, an upper limit for the fractional frequency instability of 7 x 10(-15) is measured in 1 second of averaging-a value substantially better than that of the world's best microwave atomic clocks.

4.
Phys Rev Lett ; 86(22): 4996-9, 2001 May 28.
Article in English | MEDLINE | ID: mdl-11384404

ABSTRACT

The frequency comb created by a femtosecond mode-locked laser and a microstructured fiber is used to phase coherently measure the frequencies of both the Hg+ and Ca optical standards with respect to the SI second. We find the transition frequencies to be f(Hg) = 1 064 721 609 899 143(10) Hz and f(Ca) = 455 986 240 494 158(26) Hz, respectively. In addition to the unprecedented precision demonstrated here, this work is the precursor to all-optical atomic clocks based on the Hg+ and Ca standards. Furthermore, when combined with previous measurements, we find no time variations of these atomic frequencies within the uncertainties of the absolute value of( partial differential f(Ca)/ partial differential t)/f(Ca) < or =8 x 10(-14) yr(-1) and the absolute value of(partial differential f(Hg)/ partial differential t)/f(Hg) < or =30 x 10(-14) yr(-1).

5.
RNA ; 7(4): 546-52, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11345433

ABSTRACT

Recently, Murray et al. (Chem Biol, 1998, 5:587-595) found that the hammerhead ribozyme does not require divalent metal ions for activity if incubated in high (> or =1 M) concentrations of monovalent ions. We further characterized the hammerhead cleavage reaction in the absence of divalent metal. The hammerhead is active in a wide range of monovalent ions, and the rate enhancement in 4 M Li+ is only 20-fold less than that in 10 mM Mg2+. Among the Group I monovalent metals, rate correlates in a log-linear manner with ionic radius. The pH dependence of the reaction is similar in 10 mM Mg2+, 4 M Li+, and 4 M Na+. The exchange-inert metal complex Co(NH3)3+ also supports substantial hammerhead activity. These results suggest that a metal ion does not act as a base in the reaction, and that the effects of different metal ions on hammerhead cleavage rates primarily reflect structural contributions to catalysis.


Subject(s)
Cations, Monovalent/pharmacology , RNA, Catalytic/metabolism , Base Sequence , Cations, Monovalent/chemistry , Kinetics , Models, Molecular , Molecular Sequence Data , Nucleic Acid Conformation , RNA, Catalytic/drug effects , Urea/pharmacology
6.
Opt Lett ; 26(2): 102-4, 2001 Jan 15.
Article in English | MEDLINE | ID: mdl-18033520

ABSTRACT

With a fiber-broadened, femtosecond-laser frequency comb, the 76-THz interval between two laser-cooled optical frequency standards was measured with a statistical uncertainty of 2x10(-13) in 5 s , to our knowledge the best short-term instability thus far reported for an optical frequency measurement. One standard is based on the calcium intercombination line at 657 nm, and the other, on the mercury ion electric-quadrupole transition at 282 nm. By linking this measurement to the known Ca frequency, we report a new frequency value for the Hg(+) clock transition with an improvement in accuracy of ~10(5) compared with its best previous measurement.

7.
Proc Natl Acad Sci U S A ; 97(7): 3298-303, 2000 Mar 28.
Article in English | MEDLINE | ID: mdl-10725348

ABSTRACT

The process of gene unscrambling in hypotrichous ciliates represents one of nature's ingenious solutions to the problem of gene assembly. With some essential genes scrambled in as many as 51 pieces, these ciliates rely on sequence and structural cues to rebuild their fragmented genes and genomes. Here we report the complex pattern of scrambling in the DNA polymerase alpha gene of Stylonychia lemnae. The germline (micronuclear) copy of this gene is broken into 48 pieces with 47 dispersed over two loci, with no asymmetry in the placement of coding segments on either strand. Direct repeats present at the boundaries between coding and noncoding sequences provide pointers to help guide assembly of the functional (macronuclear) gene. We investigate the evolution of this complex gene in three hypotrichous species.


Subject(s)
Evolution, Molecular , Oxytricha/genetics , Animals , Base Sequence , DNA Polymerase I/genetics , DNA Primers , Molecular Sequence Data , Open Reading Frames , Oxytricha/enzymology
9.
Opt Lett ; 25(21): 1603-5, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-18066290

ABSTRACT

For a neutral (40)Ca-based optical frequency standard we report a fractional frequency instability of 4 x 10(-15) in 1 s, which represents a fivefold improvement over existing atomic frequency standards. Using the technique of optical Bordé-Ramsey spectroscopy with a sample of 10(7) trapped atoms, we have resolved linewidths as narrow as 200 Hz (FWHM). With colder atoms this system could potentially achieve an instability as low as 2 x 10(-16) in 1 s. Such low instabilities are important for frequency standards and precision tests of fundamental physics.

11.
J Clin Pathol ; 24(9): 870-6, 1971 Dec.
Article in English | MEDLINE | ID: mdl-5139993

ABSTRACT

A one-week introductory course in clinical biochemical and research techniques was devised to provide a brief but concentrated experience for interested persons. Urinary creatinine concentrations were measured to demonstrate acceptable degrees of precision of a method (co-efficients of variation, 0.5-2.4%), and to give confidence by favourable comparison with routine laboratory results (day 2, mean 0.95 vs 0.94 mg/ml). Subjects then submitted themselves to one-day renal function testing, and subsequently measured their own urinary acid-base parameters by autotitrimetry and glomerular filtration rates by spectrophotometry. The values obtained for the latter fell within the normal range (85-124% of normal, corrected for age and surface area). Finally, statistical methods and a small desk-top computer were employed to compute linear regression equations, correlation coefficients, and t tests from the week's data. The course contained a number of features which stimulated learning, including active participation by the learner, and the use of meaningful materials to induce both desire for success and tolerance of mistakes.


Subject(s)
Biochemistry/education , Kidney Function Tests , Australia , Creatine/blood , Creatine/urine , Curriculum , Glomerular Filtration Rate , Humans , Hydrogen-Ion Concentration , Interprofessional Relations , Learning , Spectrophotometry , Statistics as Topic , Urine
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