The physical map of {\it Escherichia coli\/} K-12 strain MG1655: Construction, comparison with other strains and implications for mechanisms controlling oligonucleotide frequency

Complete NotI, SfiI, XbaI and BlnI cleavage maps of Escherichia coli K-12 strain MG1655 were constructed. Techniques used included: CHEF pulsed field gel electrophoresis; transposon mutagenesis; fragment hybridization to the ordered $\lambda$ library of Kohara et al.; fragment and cosmid hybridization to Southern blots; correlation of fragments and cleavage sites with EcoMap, a sequence-modified version of the genomic restriction map of Kohara et al.; and correlation of cleavage sites with DNA sequence databases. In all, 105 restriction sites were mapped and correlated with the EcoMap coordinate system.^ NotI, SfiI, XbaI and BlnI restriction patterns of five commonly used E. coli K-12 strains were compared to those of MG1655. The variability between strains, some of which are separated by numerous steps of mutagenic treatment, is readily detectable by pulsed-field gel electrophoresis. A model is presented to account for the difference between the strains on the basis of simple insertions, deletions, and in one case an inversion. Insertions and deletions ranged in size from 1 kb to 86 kb. Several of the larger features have previously been characterized and some of the smaller rearrangements can potentially account for previously reported genetic features of these strains.^ Some aspects of the frequency and distribution of NotI, SfiI, XbaI and BlnI cleavage sites were analyzed using a method based on Markov chain theory. Overlaps of Dam and Dcm methylase sites with XbaI and SfiI cleavage sites were examined. The one XbaI-Dam overlap in the database is in accord with the expected frequency of this overlap. The occurrence of certain types of SfiI-Dcm overlaps are overrepresented. Of the four subtypes of SfiI-Dcm overlap, only one has a partial inhibitory effect on the activity of SfiI. Recognition sites for all four enzymes are rarer than expected based on oligonucleotide frequency data, with this effect being much stronger for XbaI and BlnI than for NotI and SfiI. The latter two enzyme sites are rare mainly due to apparent negative selection against GGCC (both) and CGGCCG (NotI). The former two enzyme sites are rare mainly due to effects of the VSP repair system on certain di-tri- and tetranucleotides, most notably CTAG. Models are proposed to explain several of the anomalies of oligonucleotide distribution in E. coli, and the biological significance of the systems that produce these anomalies is discussed. ^

Energy expenditure, body-part discomfort and mental work load among nurses

The purpose of this prospective observational field study was to present a model for measuring energy expenditure among nurses and to determine if there was a difference between the energy expenditure of nurses providing direct care to adult patients on general medical-surgical units in two major metropolitan hospitals and a recommended energy expenditure of 3.0 kcal/minute over 8 hours. One-third of the predicted cycle ergometer VO2max for the study population was used to calculate the recommended energy expenditure.^ Two methods were used to measure energy expenditure among participants during an 8 hour day shift. First, the Energy Expenditure Prediction Program (EEPP) developed by the University of Michigan Center for Ergonomics was used to calculate energy expenditure using activity recordings from observation (OEE; n = 39). The second method used ambulatory electrocardiography and the heart rate-oxygen consumption relationship (HREE; n = 20) to measure energy expenditure. It was concluded that energy expenditure among nurses can be estimated using the EEPP. Using classification systems from previous research, work load among the study population was categorized as "moderate" but was significantly less than (p = 0.021) 3.0 kcal/minute over 8 hours or 1/3 of the predicted VO2max.^ In addition, the relationships between OEE, body-part discomfort (BPCDS) and mental work load (MWI) were evaluated. The relationships between OEE/BPCDS and OEE/MWI were not significant (p = 0.062 and 0.091, respectively). Among the study population, body-part discomfort significantly increased for upper arms, mid-back, lower-back, legs and feet by mid-shift and by the end of the shift, the increase was also significant for neck and thighs.^ The study also provided documentation of a comprehensive list of nursing activities. Among the most important findings were the facts that the study population spent 23% of the workday in a bent posture, walked an average of 3.14 miles, and spent two-thirds of the shift doing activities other than direct patient care, such as paperwork and communicating with other departments. A discussion is provided regarding the ergonomic implications of these findings. ^

Factors determining the use of universal precautions by emergency department nurses

The Health Belief Model (HBM) provided the theoretical framework for examining Universal Precautions (UP) compliance factors by Emergency Department nurses. A random sample of Emergency Nurses Association (ENA) clinical nurses (n = 900) from five states (New York, New Jersey, California, Texas, and Florida), were surveyed to explore the factors related to their decision to comply with UP. Five-hundred-ninety-eight (598) useable questionnaires were analyzed. The responders were primarily female (84.9%), hospital based (94.6%), staff nurses (66.6%) who had a mean 8.5 years of emergency nursing experience. The nurses represented all levels of hospitals from rural (4.5%) to urban trauma centers (23.7%). The mean UP training hours was 3.0 (range 0-38 hours). Linear regression was used to analyze the four hypotheses. The first hypothesis evaluating perceived susceptibility and seriousness with reported UP use was not significant (p = $>$.05). Hypothesis 2 tested perceived benefits with internal and external barriers. Both perceived benefits and internal barriers as well as the overall regression were significant (F = 26.03, p = $<$0.001). Hypothesis 3 which tested modifying factors, cues to action, select demographic variables, and the main effects of the HBM with self reported UP compliance, was also significant (F = 12.39, p = $<$0.001). The additive effects were tested by use of a stepwise regression that assessed the contribution of each of the significant variables. The regression was significant (F = 12.39, p = $<$0.001) and explained 18% of the total variance. In descending order of contribution, the significant variables related to compliance were: internal barriers (t = $-$6.267; p = $<$0.001) such as the perception that because of the nature of the emergency care environment there is sometimes inadequate time to put on UP; cues to action (t = 3.195; p = 0.001) such as posted reminder signs or verbal reminders from peers; the number of Universal Precautions training hours (t = 3.667; p = $<$0.001) meaning that as the number of training hours increase so does compliance; perceived benefits (t = 3.466; p = 0.001) such as believing that UP will provide adequate barrier protection; and perceived susceptibility (t = 2.880; p = 0.004) such as feeling that they are at risk of exposure. ^

A study of patient satisfaction with medical care services in Yanbu al-Sinaiya, Saudi Arabia

This study attempts to provide reliable scientific data that will enable the health services department of the Royal Commission of Yanbu Al Sinaiyah, Saudi Arabia to improve the quality of health care services provided in their facilities. Patient satisfaction and dissatisfaction were investigated along seven dimensions: General satisfaction scale, Communication, Technical quality, Art of care, Continuity of care, Time spent with the doctor, and Access/Convenience/ and availability. Patient satisfaction parameters were compared for Saudi vs. non-Saudi, males vs. females, and for patients seen in the hospital vs. those seen in Al-nawa and Radwa primary care centers. The information was obtained by using a self-administered questionnaire. The results indicate that patients seen in Al-nawa primary care center were more satisfied with care than patients seen in the hospital who in turn were more satisfied than those seen in Radwa primary care center. The non-Saudi patients were more satisfied than the Saudi patients across all three facilities and satisfaction scales. The female patients were more satisfied than the male patients across all three facilities and satisfaction scales. ^

The effectiveness of a needleless intravenous system in prevention of percutaneous injury in two hospitals

This study assessed if hospital-wide implementation of a needleless intravenous connection system reduces the number of reported percutaneous injuries, overall and those specifically due to intravenous connection activities.^ Incidence rates were compared before and after hospital-wide implementation of a needleless intravenous system at two hospitals, a full service general hospital and a pediatric hospital. The years 1989-1991 were designated as pre-implementation and 1993 was designated as post-implementation. Data from 1992 were not included in the effectiveness evaluation to allow employees to become familiar with use of the new device. The two hospitals showed rate ratios of 1.37 (95% CI = 1.22-1.54, p $\le$.0001) and 1.63 (95% CI = 1.34-1.97, p $\le$.0001), or a 27.1% and a 38.6% reduction in overall injury rate, respectively. Rate ratios for intravenous connection injuries were 2.67 (95% CI = 1.89-3.78, p $\le$.0001) and 3.35 (95% CI = 1.87-6.02, p $\le$.0001), or a 62.5% and a 69.9% reduction in injury rate, respectively. Rate ratios for all non-intravenous connection injuries were calculated to control for factors other than device implementation that may have been operating to reduce the injury rate. These rate ratios were lower, 1.21 and 1.44, demonstrating the magnitude of injury reduction due to factors other than device implementation. It was concluded that the device was effective in reduction of numbers of reported percutaneous injuries.^ Use-effectiveness of the system was also assessed by a survey of randomly selected device users to determine satisfaction with the device, frequency of use and barriers to use. Four hundred seventy-eight surveys were returned for a response rate of 50.9%. Approximately 94% of respondents at both hospitals expressed satisfaction with the needleless system and recommended continued use. The survey also revealed that even though over 50% of respondents report using the device "always" or "most of the time" for intravenous medication administration, flushing lines, and connecting secondary intravenous lines, needles were still being used for these same activities. Compatibility, accessibility and other technical problems were reported as reasons for using needles for these activities. These problems must be addressed, by both manufacturers and users, before the needleless system will be effective in prevention of all intravenous connection injuries. ^

Survey of shift and work tolerance of City of Houston emergency medical service personnel

This study of ambulance workers for the emergency medical services of the City of Houston studied the factors related to shiftwork tolerance and intolerance. The EMS personnel work a 24-hour shift with rotating days of the week. Workers are assigned to A, B, C, D shift, each of which rotate 24-hours on, 24-hours off, 24-hours on and 4 days off. One-hundred and seventy-six male EMTs, paramedics and chauffeurs from stations of varying levels of activity were surveyed. The sample group ranged in age from 20 to 45. The average tenure on the job was 8.2 years. Over 68% of the workers held a second job, the majority of which worked over 20 hours a week at the second position.^ The survey instrument was a 20-page questionnaire modeled after the Folkard Standardized Shiftwork Index. In addition to demographic data, the survey tool provided measurements of general job satisfaction, sleep quality, general health complaints, morningness/eveningness, cognitive and somatic anxiety, depression, and circadian types. The survey questionnaire included an EMS-specific scaler of stress.^ A conceptual model of Shiftwork Tolerance was presented to identify the key factors examined in the study. An extensive list of 265 variables was reduced to 36 key variables that related to: (1) shift schedule and demographic/lifestyle factors, (2) individual differences related to traits and characteristics, and (3) tolerance/intolerance effects. Using the general job satisfaction scaler as the key measurement of shift tolerance/intolerance, it was shown that a significant relationship existed between this dependent variable and stress, number of years working a 24-hour shift, sleep quality, languidness/vigorousness. The usual amount of sleep received during the shift, general health complaints and flexibility/rigidity (R$\sp2$ =.5073).^ The sample consisted of a majority of morningness-types or extreme-morningness types, few evening-types and no extreme-evening types, duplicating the findings of Motohashi's previous study of ambulance workers. The level of activity by station was not significant on any of the dependent variables examined. However, the shift worked had a relationship with sleep quality, despite the fact that all shifts work the same hours and participate in the same rotation schedule. ^

Advancing the theory of collective empowerment: A qualitative study

In order to fully describe the construct of empowerment and to determine possible measures for this construct in racially and ethnically diverse neighborhoods, a qualitative study based on Grounded Theory was conducted at both the individual and collective levels. Participants for the study included 49 grassroots experts on community empowerment who were interviewed through semi-structured interviews and focus groups. The researcher also conducted field observations as part of the research protocol.^ The results of the study identified benchmarks of individual and collective empowerment and hundreds of possible markers of collective empowerment applicable in diverse communities. Results also indicated that community involvement is essential in the selection and implementation of proper measures. Additional findings were that the construct of empowerment involves specific principles of empowering relationships and particular motivational factors. All of these findings lead to a two dimensional model of empowerment based on the concepts of relationships among members of a collective body and the collective body's desire for socio-political change.^ These results suggest that the design, implementation, and evaluation of programs that foster empowerment must be based on collaborative ventures between the population being served and program staff because of the interactive, synergistic nature of the construct. In addition, empowering programs should embrace specific principles and processes of individual and collective empowerment in order to maximize their effectiveness and efficiency. And finally, the results suggest that collaboratively choosing markers to measure the processes and outcomes of empowerment in the main systems and populations living in today's multifaceted communities is a useful mechanism to determine change. ^