Impact on Quality When Pediatric Urgent Care Centers Are Staffed With Radiology Technologists.

PURPOSE: The proliferation of pediatric urgent care centers has increased the need for diagnostic imaging support, but the impact of employing radiology technologists at these centers is not known. The purpose of this study was to evaluate radiographic impact and quality at urgent care centers with and without radiology technologists. METHODS: A retrospective case-control study was conducted comparing 235 radiographic examinations (study) performed without and 83 examinations (control) performed with a radiology technologist at the authors' pediatric urgent care centers. Studies were evaluated for quality using a five-point, Likert-type scale (1 = poor, 5 = best) regarding field of view, presentation, and orthogonal view orientation. Studies were also evaluated for the incidence of positive results, need for repeat imaging, and discrepancies between initial study and follow-up. RESULTS: Imaging quality comparisons between study and control groups were statistically different for field of view (3.98 versus 4.29, P = .014), presentation (4.39 versus 4.51, P = .045), and orthogonal view orientation (4.45 versus 4.69, P = .033). The incidence of repeat imaging was similar (4.7% versus 2.4%, P = 0.526), as well as the discrepancy rates (3.4 versus 2.4%, P = 1.00). The incidence of abnormal radiographic findings for the study and control groups was similar (40.9% versus 34.9%, P = .363). CONCLUSIONS: Radiography is an important triage tool at pediatric urgent care centers. It is imperative to have optimal radiographic imaging for accurate diagnosis, and imaging quality is improved when radiology technologists are available. If not feasible or cost prohibitive, it is important that physicians be given training opportunities to bridge the quality gap when using radiographic equipment and exposing children to radiation.

Anion photoelectron spectroscopy of C3N- and C5N-.

Anion photoelectron spectroscopy of C(3)N(-) and C(5)N(-) is performed using slow electron velocity-map imaging (SEVI) and field-free time-of-flight (TOF), respectively. The SEVI spectrum exhibits well-resolved vibrational transitions from the linear C(3)N(-) ground state to the corresponding C(3)N ground state. The TOF spectrum comprises transitions arising from the linear C(5)N(-) ground state to the corresponding neutral ground and excited states. This study yields the adiabatic electron affinities of C(3)N and C(5)N to be 4.305 +/- 0.001 and 4.45 +/- 0.03 eV, respectively, and a term value of 560 +/- 120 cm(-1) for the A(2)Pi state of C(5)N. Vibrational frequencies for the degenerate cis and trans bending modes of C(3)N(-) are also extracted.

Anion photoelectron spectroscopy of C(5)H(-).

Anion photoelectron spectroscopy is performed on the C(5)H(-) species. Analogous to C(3)H(-) and C(3)D(-), photodetachment transitions are observed from multiple, energetically close-lying isomers of the anion. A linear and a cyclic structure are found to have electron binding energies of 2.421+/-0.019 eV and 2.857+/-0.028 eV, respectively. A cyclic excited state is also found to be 1.136 eV above the linear (2)Pi C(5)H ground state. Based on our assignments of the observed transitions and previous calculations on the energetics of neutral C(5)H isomers, the cyclic (1)A(1) anion state is found to lie 0.163 eV below the (3)A linear anion.

Characterization of cyclic and linear C3H- and C3H via anion photoelectron spectroscopy.

Anion photoelectron spectroscopy of C3H- and C3D- is performed using both field-free time-of-flight and slow electron velocity-map imaging. We observe and assign transitions originating from linear/bent (l-C3H) and cyclic (c-C3H) anionic isomers to the corresponding neutral ground states and low-lying excited states. Transitions within the cyclic and linear manifolds are distinguished by their photoelectron angular distributions and their intensity dependence on the neutral precursor. Using calculated values for the energetics of the neutral isomers [Ochsenfeld et al., J. Chem. Phys. 106, 4141 (1997)], which predict c-C3H to lie 74 meV lower than l-C3H, the experimental results establish c-C3H- as the anionic ground state and place it 229 meV below l-C3H-. Electron affinities of 1.999+/-0.003 and 1.997+/-0.005 eV are determined for C3H and C3D from the X 2B2<--X 1A1 photodetachment transition of c-C3H. Term energies for several low-lying states of c-C3H and l-C3H are also determined. Franck-Condon simulations are used to make vibrational assignments for the bands involving c-C3H. Simulations of the l-C3H bands were more complicated owing to large amplitude bending motion and, in the case of the neutral A 2Pi state, strong Renner-Teller coupling.

Anion photoelectron imaging of deprotonated thymine and cytosine.

We report the anion photoelectron spectra of deprotonated thymine and cytosine at 3.496 eV photodetachment energy using velocity-mapped imaging. The photoelectron spectra of both species exhibit bands resulting from detachment transitions between the anion ground state and the ground state of the neutral radical. Franck-Condon simulations identify the anion isomers that contribute to the observed photoelectron spectrum. For both thymine and cytosine, the photoelectron spectra are consistent with anions formed by removal of a proton from the N atom that normally attaches to the sugar in the nucleotide (N1). For deprotonated thymine, the photoelectron spectrum shows a band due to a ring breathing vibration excited during the photodetachment transition. The electron affinity for the dehydrogenated thymine radical is determined as 3.250 +/- 0.015 eV. For deprotonated cytosine, the photoelectron spectrum lacks any resolved structure and the electron affinity of the dehydrogenated cytosine radical is determined to be 3.037 +/- 0.015 eV. By combining the electron affinity with previously measured gas phase acidities of thymine and cytosine, we determine the bond dissociation energy for the N-H bond that is broken.

Photoelectron imaging of I2- at 5.826 eV.

We report the anion photoelectron spectrum of I2- taken at 5.826 eV detachment energy using velocity mapped imaging. The photoelectron spectrum exhibits bands resulting from transitions to the bound regions of the X 1Sigmag+(0g+), A' 3Piu(2u), A 3Piu(1u), and B 3Piu(0u+) electronic states as well as bands resulting from transitions to the repulsive regions of several I2 electronic states: the B' 3Piu(0u-), B" 1Piu(1u), 3Pig(2g), a 3Pig(1g), 3Pig(0g-), and C 3Sigmau+(1u) states. We simulate the photoelectron spectrum using literature parameters for the I2- and I2 ground and excited states. The photoelectron spectrum includes bands resulting from transitions to several high-lying excited states of I2 that have not been seen experimentally: 3Pig(0g-), 1Pig3(1g), 1 3Sigmag-3(0g+), and the 1Sigmag-3(0u-) states of I2. Finally, the photoelectron spectrum at 5.826 eV allows for the correction of a previous misassignment for the vertical detachment energy of the I2 B 3Piu(0u+) state.