Young Hae Kim

Path Analysis of Empowerment and Work Effectiveness among Staff Nurses

PURPOSE The purpose of this study was to test a predictive model that could predict and explain work effectiveness among staff nurses at local hospitals. METHODS Between April 1 and May 15, 2009, 340 nurses were recruited from two hospitals (one in Ulsan and one in Yangsan). Data were collected via self-administered questionnaires and analyzed using structural equation modeling. RESULTS A modified model was retained, as the final path model showed a very good fit with the data. Job characteristics and compensation justice were found to have direct and positive effects on empowerment. Job characteristics, transformational leadership, and empowerment were found to directly and positively affect work effectiveness. In addition, job characteristics were found to have a greater effect on empowerment and work effectiveness than other factors do. CONCLUSION This structural equation model was used to test the relationships between these factors and work effectiveness. Empowerment mediated the relationship between job characteristics, transformational leadership, and work effectiveness. Findings from this study can be used to design the strategies for increasing work effectiveness in Korean nurses.

Evaluation of Natural Attenuation by Addition of Fumarate as Carbon Source and Gene Analysis in Groundwater Sample

In the results of monitoring nitrate concentration in more than 8,000 groundwater wells around agro-livestock, the average and maximum nitrate concentration was 9.4 mg/L and 101.2 mg/L, respectively. Since about 31% of the monitoring wells was exceed the quality standard for drinking water, nitrate control such as remediation or source regulation is required to conserve safe-groundwater in South Korea. Typical nitrate-treatment technologies include ion exchange, reverse osmosis, and biological denitrification. Among the treatment methods, biological denitrification by indigenous microorganism has environmental and economic advantages for the complete elimination of nitrate because of lower operating costs compared to other methods. Major mechanism of the process is microbial reduction of nitrate to nitrite and nitrogen gas. Three functional genes (nosZ, nirK, nirS) that encode for the enzyme involved in the pathway. In this work, we tried to develop simple process to determine possibility of natural denitrification reaction by monitoring the functional gene. For the work, the functional genes in nitrate-contaminated groundwater were monitored by using PCR with specific target primers. In the result, functional genes (nosZ and nirK) encoding denitrification enzymes were detected in the groundwater samples. This method can help to determine the possibility of natural-nitrate degradation in target groundwater wells without multiplex experimental process. In addition, for field-remediation application we selected nitrate-contaminated site where 200~600 mg/L of nitrate is continuously detected. To determine the possibility of nitrate-degradation by stimulated-natural attenuation, groundwater was sampled in two different wells of the site and nitrate concentration of the samples was 300 mg/L and 616 mg/L, respectively. Fumarate for different C/N ratio was added into microcosm bottles containing the groundwater to examine denitrification rate depending on carbon concentration. In the result, once 1.5 times more than amount of fumarate stoichiometry required was added, the 616 mg/L of nitrate and 300 mg/L of nitrate were completely degraded in 8 days and 30 days. The nitrite, byproduct of denitrification process, was also completely degraded during the experimental period.

Evaluation of Denitrification Efficiency and Functional Gene Change According to Carbon(Fumarate) Concentration and Addition of Nitrate Contaminated-soil in Batch System

Nitrate is on the most seriou pollutant encountered in shallow groundwater aquifer in agricultural area. There are various remediation technologies such as ion exchange, reverse osmosis, and biological denitrification to recover from nitrate contamination. Biological denitrification by indigenous microorganism of the technologies has been reviewed and applied on nitrate contaminated groundwater. In this work, we selected the site where the annual nitrate (NO3−) concentration is over 105 mg/L and evaluated denitrification process with sampled soil and groundwater from 3 monitoring wells (MW4, 5, 6). In the results, the nitrate degradation rate in each well (MW 4, 5, and 6) was 25 NO3− mg/L/day, 6 NO3− mg/L/day, and 3.4 NO3− mg/L/day, respectively. Nitrate degradation rate was higher in batch system treated with 2 times higher fumarate as carbon source than control batch system (0.42M fumrate/1M NO3−), comparing with batch system with soil sample. This result indicates that increase of carbon source is more efficient to enhance denitrification rate than addition of soil sample to increase microbial dynamics. In this work, we also confirmed that monitoring method of functional genes (nirK and nosZ) involved in denitrification process can be applied to evaluated denitrifcation process possibility before application of field process such as in-situ denitrification by push-pull test.

Monitoring Anaerobic Reductive Dechlorination of TCE by Biofilm-Type Culture in Continuous-Flow System

A 1.28 L-batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloroethene (TCE) were operated for 120 days and 56 days, respectively, to study the effect of formate as electron donor on anaerobic reductive dechlorination (ARD) of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 µmol TCE was completely degraded in the presence of 20% hydrogen gas (H2) in less than 8 days by anaerobic dechlorination mixed-culture (300 mg-soluble protein), Evanite Culture with ability to completely degrade tetrachloroethene (PCE) and -TCE to ETH under anaerobic conditions. Once the formate was used as electron donor instead of hydrogen gas in batch or chemostat system, the TCE-dechlorination rate decreased and acetate production rate increased. It indicates that the concentration of hydrogen produced in both systems is possibly more close to threshold for homoacetogenesis process. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. Through the protein monitoring, we confirmed an increase of microbial population during the reactor operation. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 µmol/L) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at 18 days of HRT, but TCE was completely degraded at 36 days of HRT without accumulation of the injected-TCE during the left of experiment period, getting H2 from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after beginning of CFSTR operation, it reached steady-state in the presence of excessive formate. We also evaluated microbial dynamic of the culture at different chemical state in the reactor by DGGE (denaturing gradient gel electrophoresis).

Analysis of the Characteristics and the Nursing Interventions for Children in Regional Emergency Departments -Using the Nursing Intervention Classification-

Purpose: The purpose of this study was to provide descriptive data about the characteristics of pediatric patients and nursing interventions in Regional Emergency Medical Centers (REMC). Methods: A retrospective design was used to examine the medical records of 4,310 children. The clinical data and nursing terminologies of REMC were analyzed using the Nursing Intervention Classification (NIC). Results: Male toddlers dominated the sample. The mean age of the children was 3.51 yr. In more than half of the visits, patients arrived between from 7 a.m. to 3 p.m., on a weekday. There were only 189 ambulance transports to REMC, (4.4% of visits). The most frequent injuries were due to falls (28.0%) and contusions (27.3%), but the most common reasons for visits were non-injury (73.4%): fever, cough/shortness of breath, seizures, and abdominal pain. Of the 4,310 visits, 27.8% spent 6-24 hours in the REMC, while 33% resulted in hospital admission and 2.1% in transfer to another hospital. Of the 17,929 nursing interventions, 17,909 elements (99.9%) were classified under NIC. All the listed NIC interventions, however, were not reflected in the level of practice demonstrated by REMC nurses. Conclusion: These results can enhance the understanding of pediatric emergency nursing interventions and can make NIC more applicable.