Cross sections for the reaction 1H(e,e′π+)n were measured in Hall C at Thomas Jefferson National Accelerator Facility (JLab) using the CEBAF high-intensity, continous electron beam in order to ...determine the charged pion form factor. Data were taken for central four-momentum transfers ranging from Q2=0.60 to 2.45 GeV2 at an invariant mass of the virtual photon-nucleon system of W=1.95 and 2.22 GeV. The measured cross sections were separated into the four structure functions σL, σT, σLT, and σTT. The various parts of the experimental setup and the analysis steps are described in detail, including the calibrations and systematic studies, which were needed to obtain high precision results. The different types of systematic uncertainties are also discussed. The results for the separated cross sections as a function of the Mandelstam variable t at the different values of Q2 are presented. Some global features of the data are discussed, and the data are compared with the results of some model calculations for the reaction 1H(e,e′π+)n.
Sequential outbreaks of infection due to gentamicin-resistant Klebsiella pneumoniae (GRKP) types 30 and 19 occurred in the neonatal intensive care unit (NICU) at the Medical College of Virginia in ...1977 and 1978. The extensive epidemiologic investigation carried out included a case-control study, careful review of aseptic technique, and cultures from nursery staff and environment. The gastrointestinal (GI) tracts of the patients were the reservoirs for GRKP, and the epidemic strain was transmitted by hands of personnel. The case-control study showed a significant relationship between acquisition of GRKP by patients and oropharyngeal and GI instrumentation, including use of bag resuscitation, oropharyngeal suctioning, and use of nasogastric feeding tubes. The findings of the case-control study were supported by observation of the patient care techniques practiced by NICU staff. Institution of control measures based on results of the epidemiologic investigation of the first outbreak rapidly brought the second outbreak under control, even though cohorting or use of routine isolation was not possible. Whereas GI colonization and hand transmission have been described previously in outbreaks of K. pneumoniae infections in NICUs, this study is the first to document the mode of inoculation of patients' GI tracts by contaminated hands of personnel.
Previously published methods for determining an appropriate aminoglycoside dosage have been adapted for use in the hand-held programmable calculator (Texas Instrument-59). The purpose of this study ...was to evaluate the accuracy of calculator-generated serum level predictions compared with measured values. Twenty-four adult patients receiving intravenous aminoglycosides (gentamicin, netilmicin, or tobramycin) had urine and serum collected for creatinine clearance calculations and had blood obtained for peak and through aminoglycoside concentration determinations. All but one patient had normal renal function. A statistically significant relationship between predicated and measured creatinine clearance values was found. There was also generally good agreement between the calculator-predicted aminoglycoside levels and the measured levels, although some patients exhibited unexplained deviations. Error in the estimation of creatinine clearance and adjustments for lean body weight did not improve prediction accuracy. We conclude that the hand-held calculator was able to predict measured aminoglycoside levels for most patients with acceptable precision. However, the calculator method offers no real advantage over other methods (except speed in performing the calculation), and may give the user a false sense of security.