Motivational profiles of sport event volunteers.

Aim of the study Due to the valuable contribution made by volunteers to sporting events, a better understanding of volunteers’ motivation is imperative for event managers in order to develop effective volunteer re-cruitment and retention strategies. The adoption of working conditions and task domains to the mo-tives and needs of volunteers is one of the key challenges in volunteer management. Conversely, an ignorance of the motives and needs of volunteers could negatively affect their performance and attitude, which will have negative consequences for the execution of events (Strigas & Jackson, 2003). In general, the motives of volunteers are located on a continuum between selflessness (e.g. helping others), and self-interest (e.g. pursuing one’s own interests). Furthermore, it should take into account that volunteers may be motivated by more than one need or goal, and therefore, configure different bundles of motives, resulting in heterogeneous types of motives for voluntary engagement (Dolnicar & Randle, 2007). Despite the extensive number of studies on the motives of sport event volunteers, only few studies focus on the analysis of individual motive profiles concerning volun-teering. Accordingly, we will take a closer look at the following questions: To what extent do volun-teers at sporting events differ in the motives of their engagement, and how can the volunteers be ade-quately classified? Theoretical Background According to the functional approach, relevant subjective motives are related to the outcomes and consequences that volunteering is supposed to lead to and to produce. This means, individuals’ mo-tives determine which incentives are anticipated in return for volunteering (e.g. increase in social contacts), and are important for engaging in volunteering, e.g. the choice between different oppor-tunities for voluntary activity, or different tasks (Stukas et al., 2009). Additionally, inter-individual differences of motive structures as well as matching motives in the reflections of voluntary activities will be considered by using a person-oriented approach. In the person-oriented approach, it is not the specific variables that are made the entities of investigation, but rather persons with a certain combination of characteristic features (Bergmann et al., 2003). Person-orientation in the field of sports event volunteers, it is therefore essential to implement an orientation towards people as a unit of analysis. Accordingly, individual motive profiles become the object of investigation. The individ-ual motive profiles permit a glimpse of intra-individual differences in the evaluation of different motive areas, and thus represent the real subjective perspective. Hence, a person will compare the importance of individual motives for his behaviour primarily in relation to other motives (e.g. social contacts are more important to me than material incentives), and make fewer comparisons with the assessments of other people. Methodology, research design and data analysis The motives of sports event volunteers were analysed in the context of the European Athletics Championships 2014 in Zürich. After data cleaning, the study sample contained a total of 1,169 volunteers, surveyed by an online questionnaire. The VMS-ISA scale developed by Bang and Chel-ladurai (2009) was used and replicated successfully by a confirmatory factor analysis. Accordingly, all seven factors of the scale were included in the subsequent cluster analysis to determine typical motive profiles of volunteers. Before proceeding with the cluster analysis, an intra-individual stand-ardization procedure (according to Spiel, 1998) was applied to take advantage of the intra-individual relationships between the motives of the volunteers. Intra-individual standardization means that every value of each motive dimension was related to the average individual level of ex-pectations. In the final step, motive profiles were determined using a hierarchic cluster analysis based on Ward’s method with squared Euclidean distances. Results, discussion and implications The results reveal that motivational processes differ among sports event volunteers, and that volunteers sometimes combine contradictory bundles of motives. In our study, four different volunteer motive profiles were identified and described by their positive levels on the individual motive dimension: the community supporters, the material incentive seekers, the social networkers, and the career and personal growth pursuers. To describe the four identified motive profiles in more detail and to externally validate them, the clusters were analysed in relation to socio-economic, sport-related, and voluntary work characteristics. This motive-based typology of sports event volunteers can provide valuable guidance for event managers in order to create distinctive and designable working conditions and tasks at sporting events that should, in relation to a person-oriented approach, be tailored to a wide range of individ-ual prerequisites. Furthermore, specific recruitment procedures and appropriate communication measures can be defined in order to approach certain groups of potential volunteers more effectively. References Bang, H., & Chelladurai, P. (2009). Development and validation of the volunteer motivations scale for international sporting events (VMS-ISE). International Journal Sport Management and Market-ing, 6, 332-350. Bergmann, L. R., Magnusson, D., & El-Khouri, B. M. (2003). Studying individual development in an interindividual context. Mahwah, NJ: Erlbaum. Dolnicar, S., & Randle, M. (2007). What motivates which volunteers? Psychographic heterogeneity among volunteers in Australia. Voluntas, 18, 135-155. Spiel, C. (1998). Four methodological approaches to the study of stability and change in develop-ment. Methods of Psychological Research Online, 3, 8-22. Stukas, A. A., Worth, K. A., Clary, E. G., & Snyder, M. (2009). The matching of motivations to affordances in the volunteer environment: an index for assessing the impact of multiple matches on volunteer outcomes. Nonprofit and Voluntary Sector Quarterly, 38, 5-28.

Effectiveness of Personal Protective Equipment for Healthcare Workers Caring for Patients with Filovirus Disease: A Rapid Review.

BACKGROUND A rapid review, guided by a protocol, was conducted to inform development of the World Health Organization's guideline on personal protective equipment in the context of the ongoing (2013-present) Western African filovirus disease outbreak, with a focus on health care workers directly caring for patients with Ebola or Marburg virus diseases. METHODS Electronic databases and grey literature sources were searched. Eligibility criteria initially included comparative studies on Ebola and Marburg virus diseases reported in English or French, but criteria were expanded to studies on other viral hemorrhagic fevers and non-comparative designs due to the paucity of studies. After title and abstract screening (two people to exclude), full-text reports of potentially relevant articles were assessed in duplicate. Fifty-seven percent of extraction information was verified. The Grading of Recommendations Assessment, Development and Evaluation framework was used to inform the quality of evidence assessments. RESULTS Thirty non-comparative studies (8 related to Ebola virus disease) were located, and 27 provided data on viral transmission. Reporting of personal protective equipment components and infection prevention and control protocols was generally poor. CONCLUSIONS Insufficient evidence exists to draw conclusions regarding the comparative effectiveness of various types of personal protective equipment. Additional research is urgently needed to determine optimal PPE for health care workers caring for patients with filovirus.

Posterior Vertical Bite Reconstructions of Erosively Worn Dentitions and the "Stamp Technique" - A Case Series with a Mean Observation Time of 40 Months

PURPOSE In the present case series, the authors report on seven cases of erosively worn dentitions (98 posterior teeth) which were treated with direct resin composite. MATERIALS AND METHODS In all cases, both arches were restored by using the so-called stamp technique. All patients were treated with standardized materials and protocols. Prior to treatment, a waxup was made on die-cast models to build up the loss of occlusion as well as ensure the optimal future anatomy and function of the eroded teeth to be restored. During treatment, teeth were restored by using templates of silicone (ie, two "stamps," one on the vestibular, one on the oral aspect of each tooth), which were filled with resin composite in order to transfer the planned, future restoration (ie, in the shape of the waxup) from the extra- to the intraoral situation. Baseline examinations were performed in all patients after treatment, and photographs as well as radiographs were taken. To evaluate the outcome, the modified United States Public Health Service criteria (USPHS) were used. RESULTS The patients were re-assessed after a mean observation time of 40 months (40.8 ± 7.2 months). The overall outcome of the restorations was good, and almost exclusively "Alpha" scores were given. Only the marginal integrity and the anatomical form received a "Charlie" score (10.2%) in two cases. CONCLUSION Direct resin composite restorations made with the stamp technique are a valuable treatment option for restoring erosively worn dentitions.

Evaluation of the success of medical management for presumptive cervical intervertebral disk herniation in dogs.

OBJECTIVE To determine the success of medical management of presumptive cervical disk herniation in dogs and variables associated with treatment outcome. DESIGN Retrospective case series. ANIMALS Dogs (n=88) with presumptive cervical disk herniation. METHODS Dogs with presumptive cervical and thoracolumbar disk herniation were identified from medical records at 2 clinics and clients were mailed a questionnaire related to the success of therapy, clinical recurrence of signs, and quality of life (QOL) as interpreted by the owner. Signalment, duration and degree of neurologic dysfunction, and medication administration were determined from medical records. RESULTS Ninety-seven percent of dogs (84/87) with complete information were described as ambulatory at initial evaluation. Successful treatment was reported for 48.9% of dogs with 33% having recurrence of clinical signs and 18.1% having therapeutic failure. Bivariable logistic regression showed that non-steroidal anti-inflammatory drug (NSAID) administration was associated with success (P=.035; odds ratio [OR]=2.52). Duration of cage rest and glucocorticoid administration were not significantly associated with success or QOL. Dogs with less-severe neurologic dysfunction were more likely to have a successful outcome (OR=2.56), but this association was not significant (P=.051). CONCLUSIONS Medical management can lead to an acceptable outcome in many dogs with presumptive cervical disk herniation. Based on these data, NSAIDs should be considered as part of the therapeutic regimen. Cage rest duration and glucocorticoid administration do not appear to benefit these dogs, but this should be interpreted cautiously because of the retrospective data collection and use of client self-administered questionnaire follow-up. CLINICAL RELEVANCE These results provide insight into the success of medical management for presumptive cervical disk herniation in dogs and may allow for refinement of treatment protocols.

Effect of the REG1 anticoagulation system versus bivalirudin on outcomes after percutaneous coronary intervention (REGULATE-PCI): a randomised clinical trial.

BACKGROUND REG1 is a novel anticoagulation system consisting of pegnivacogin, an RNA aptamer inhibitor of coagulation factor IXa, and anivamersen, a complementary sequence reversal oligonucleotide. We tested the hypothesis that near complete inhibition of factor IXa with pegnivacogin during percutaneous coronary intervention, followed by partial reversal with anivamersen, would reduce ischaemic events compared with bivalirudin, without increasing bleeding. METHODS We did a randomised, open-label, active-controlled, multicentre, superiority trial to compare REG1 with bivalirudin at 225 hospitals in North America and Europe. We planned to randomly allocate 13,200 patients undergoing percutaneous coronary intervention in a 1:1 ratio to either REG1 (pegnivacogin 1 mg/kg bolus [>99% factor IXa inhibition] followed by 80% reversal with anivamersen after percutaneous coronary intervention) or bivalirudin. Exclusion criteria included ST segment elevation myocardial infarction within 48 h. The primary efficacy endpoint was the composite of all-cause death, myocardial infarction, stroke, and unplanned target lesion revascularisation by day 3 after randomisation. The principal safety endpoint was major bleeding. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, identifier NCT01848106. The trial was terminated early after enrolment of 3232 patients due to severe allergic reactions. FINDINGS 1616 patients were allocated REG1 and 1616 were assigned bivalirudin, of whom 1605 and 1601 patients, respectively, received the assigned treatment. Severe allergic reactions were reported in ten (1%) of 1605 patients receiving REG1 versus one (<1%) of 1601 patients treated with bivalirudin. The composite primary endpoint did not differ between groups, with 108 (7%) of 1616 patients assigned REG1 and 103 (6%) of 1616 allocated bivalirudin reporting a primary endpoint event (odds ratio [OR] 1·05, 95% CI 0·80-1·39; p=0·72). Major bleeding was similar between treatment groups (seven [<1%] of 1605 receiving REG1 vs two [<1%] of 1601 treated with bivalirudin; OR 3·49, 95% CI 0·73-16·82; p=0·10), but major or minor bleeding was increased with REG1 (104 [6%] vs 65 [4%]; 1·64, 1·19-2·25; p=0·002). INTERPRETATION The reversible factor IXa inhibitor REG1, as currently formulated, is associated with severe allergic reactions. Although statistical power was limited because of early termination, there was no evidence that REG1 reduced ischaemic events or bleeding compared with bivalirudin. FUNDING Regado Biosciences Inc.

Source apportionment and dynamic changes of carbonaceous aerosols during the haze bloom-decay process in China based on radiocarbon and organic molecular tracers

Fine carbonaceous aerosols (CAs) is the key factor influencing the currently filthy air in megacities in China, yet few studies simultaneously focus on the origins of different CAs species using specific and powerful source tracers. Here, we present a detailed source apportionment for various CAs fractions, including organic carbon (OC), water-soluble OC (WSOC), water-insoluble OC (WIOC), elemental carbon (EC) and secondary OC (SOC) in the largest cities of North (Beijing, BJ) and South China (Guangzhou, GZ), using the measurements of radiocarbon and anhydrosugars. Results show that non-fossil fuel sources such as biomass burning and biogenic emission make a significant contribution to the total CAs in Chinese megacities: 56±4 in BJ and 46±5% in GZ, respectively. The relative contributions of primary fossil carbon from coal and liquid petroleum combustions, primary non-fossil carbon and secondary organic carbon (SOC) to total carbon are 19, 28 and 54% in BJ, and 40, 15 and 46% in GZ, respectively. Non-fossil fuel sources account for 52 in BJ and 71% in GZ of SOC, respectively. These results suggest that biomass burning has a greater influence on regional particulate air pollution in North China than in South China. We observed an unabridged haze bloom-decay process in South China, which illustrates that both primary and secondary matter from fossil sources played a key role in the blooming phase of the pollution episode, while haze phase is predominantly driven by fossil-derived secondary organic matter and nitrate.

A picture of trends in Aujeszky's disease virus exposure in wild boar in the Swiss and European contexts.

BACKGROUND In parallel to the increase of wild boar abundance in the past decades, an increase of exposure to the Aujeszky's disease virus (ADV) has been reported in wild boar in several parts of Europe. Since high animal densities have been proposed to be one of the major factors influencing ADV seroprevalence in wild boar populations and wild boar abundance has increased in Switzerland, too, a re-evaluation of the ADV status was required in wild boar in Switzerland. We tested wild boar sera collected from 2008-2013 with a commercial ELISA for antibodies against ADV. To set our data in the European context, we reviewed scientific publications on ADV serosurveys in Europe for two time periods (1995-2007 and 2008-2014). RESULTS Seven out of 1,228 wild boar sera were positive for antibodies against ADV, resulting in an estimated seroprevalence of 0.57% (95% confidence interval CI: 0.32-0.96%). This is significantly lower than the prevalence of a previous survey in 2004-2005. The literature review revealed that high to very high ADV seroprevalences are reported from Mediterranean and Central-eastern countries. By contrast, an "island" of low to medium seroprevalences is observed in the centre of Europe with few isolated foci of high seroprevalences. We were unable to identify a general temporal trend of ADV seroprevalence at European scale. CONCLUSIONS The seroprevalence of ADV in wild boar in Switzerland belongs among the lowest documented in Europe. Considering the disparity of seroprevalences in wild boar in Europe, the fact that seroprevalences in Switzerland and other countries have decreased despite increasing wild boar densities and the knowledge that stress leads to the reactivation of latent ADV with subsequent excretion and transmission, we hypothesize that not only animal density but a range of factors leading to stress - such as management - might play a crucial role in the dynamics of ADV infections.

A case-control study to estimate the effects of acute clinical infection with the Schmallenberg virus on milk yield, fertility and veterinary costs in Swiss dairy herds.

Schmallenberg virus (SBV) was first detected in Switzerland in July 2012 and many Swiss dairy farmers reported acute clinical signs in dairy cattle during the spread of the virus until December 2012. The objectives of the present study were to investigate the effects of an acute infection with SBV on milk yield, fertility and veterinary costs in dairy farms with clinical signs of SBV infection (case farms), and to compare those farms to a matched control group of dairy farms in which cattle did not show clinical signs of SBV infection. Herd size was significantly (p<0.001) larger in case farms (33 cows, n=77) than in control farms (25 cows, n=84). Within case herds, 14.8% (median) of the cows showed acute clinical signs. Managers from case farms indicated to have observed a higher abortion rate during the year with SBV (6.5%) than in the previous year (3.7%). Analysis of fertility parameters based on veterinary bills and data from the breeding associations showed no significant differences between case and control farms. The general veterinary costs per cow from July to December 2012 were significantly higher (p=0.02) in case (CHF 19.80; EUR 16.50) than in control farms (CHF 15.90; EUR 13.25). No differences in milk yield were found between groups, but there was a significant decrease in milk production in case farms in the second half year in 2012 compared to the same period in 2011 (p<0.001) and 2013 (p=0.009). The average daily milk yield per cow (both groups together) was +0.73kg higher (p=0.03) in the second half year 2011 and +0.52kg (p=0.12) in the second half year 2013 compared to the same half year 2012. Fifty-seven percent of the cows with acute clinical signs (n=461) were treated by a veterinarian. The average calculated loss after SBV infection for a standardized farm was CHF 1606 (EUR 1338), which can be considered as low at the national level, but the losses were subject to great fluctuations between farms, so that individual farms could have very high losses (>CHF 10,000, EUR 8333).

Total Synthesis of Prostaglandin 15d-PGJ(2) and Investigation of its Effect on the Secretion of IL-6 and IL-12.

An efficient synthesis of 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2, 1) is reported. The route described allows for diversification of the parent structure to prepare seven analogues of 1 in which the positioning of electrophilic sites is varied. These analogues were tested in SAR studies for their ability to reduce the secretion of proinflammatory cytokines. It was shown that the endocyclic enone is crucial for the bioactivity investigated and that the conjugated ω-side chain serves in a reinforcing manner.

The Perceived Prognosis of Endodontic Treatment and Implant Therapy Among Dental Practitioners

Little data concerning the perceived success of implant therapy in comparison with endodontic treatment exists. While the criteria used to measure the outcome of each modality are not the same, it is not clear if this is appreciated by practicing dentists. The purpose of the study was to evaluate the perceived outcome of implant therapy in comparison to endodontic treatment. A 23 question Web-based survey was distributed to 648 dentists who matriculated from the University of Connecticut School Of Dental Medicine over the past 30 years. The response rate was 47%. Sixty-seven percent of respondents were general dentists. Forty-nine percent of respondents did not know different criteria exist in the literature and are used to evaluate implant and root canal treatment. Fifty-four percent of dentists felt the prognosis of implant therapy was the same as or better than endodontic treatment of teeth with vital pulps. Thirty percent of responders thought root canal treatment of teeth with necrotic pulp was superior to implants and only 16% thought retreatment was preferable. Treatment planning for implant placement vs. retreatment of a restorable tooth was 46% and 32%, respectively. A third of the respondents felt that the role of endodontics will decline in the future. Dentists’ primary source of information regarding implant therapy was continuing education; however, their primary source of information regarding endodontic treatment was their dental program. Dentists felt the prognosis of implant therapy was as good or superior to endodontic treatment of teeth with vital, necrotic or previously treated pulps.

VERIFICATION OF DNA PREDICTED PROTEIN SEQUENCES BY ENZYME HYDROLYSIS AND MASS SPECTROMETRIC ANALYSIS

The focus of this thesis lies in the development of a sensitive method for the analysis of protein primary structure which can be easily used to confirm the DNA sequence of a protein's gene and determine the modifications which are made after translation. This technique involves the use of dipeptidyl aminopeptidase (DAP) and dipeptidyl carboxypeptidase (DCP) to hydrolyze the protein and the mass spectrometric analysis of the dipeptide products.^ Dipeptidyl carboxypeptidase was purified from human lung tissue and characterized with respect to its proteolytic activity. The results showed that the enzyme has a relatively unrestricted specificity, making it useful for the analysis of the C-terminal of proteins. Most of the dipeptide products were identified using gas chromatography/mass spectrometry (GC/MS). In order to analyze the peptides not hydrolyzed by DCP and DAP, as well as the dipeptides not identified by GC/MS, a FAB ion source was installed on a quadrupole mass spectrometer and its performance evaluated with a variety of compounds.^ Using these techniques, the sequences of the N-terminal and C-terminal regions and seven fragments of bacteriophage P22 tail protein have been verified. All of the dipeptides identified in these analysis were in the same DNA reading frame, thus ruling out the possibility of a single base being inserted or deleted from the DNA sequence. The verification of small sequences throughout the protein sequence also indicates that no large portions of the protein have been removed after translation. ^

Texas Department of Health organizational structure changes: A reflection of public health policy and agency expansion, September 1, 1946--June 30, 1994

The premise of this study is that changes in the agency's organizational structure reflect changes in government public health policy. Based on this premise, this study tracks the changes in the organizational structure and the overall expansion of the Texas Department of Health to understand the evolution of changing public health priorities in state policy from September 1, 1946 through June 30, 1994, a period of growth and new responsibilities. It includes thirty-seven observations of organizational structure as depicted by organizational charts of the agency and/or adapted from public documents. ^ The major questions answered are, what are the changes in the organizational structure, why did they occur and, what are the policy priorities reflected in these changes in and across the various time periods. ^ The analysis of the study included a thorough review of the organizational structure of the agency for the time-span of the study, the formulation of the criteria to be used in ascertaining the changes, the delineation of the changes in the organizational structure and comparison of the observations sequentially to characterize the change, the discovery of reasons for the structural changes (financial, statutory - federal and state, social and political factors), and the determination of policy priorities for each time period and their relation to the expansion and evolution of the agency. ^ The premise that the organizational structure of the agency and the changes over time reflect government public health policy and agency expansion was found to be true. ^

A geographic analysis of liver cancer mortality and alcohol dependence or abuse in Texas and the U.S., 1980--2003

Background. Liver cancer mortality continues to be a significant factor in deaths worldwide and in the U.S., yet there remains a lack of studies on how mortality burden is impacted by racial groups or by heavy alcohol use. This study evaluated the geographic distribution of liver cancer mortality across population groups in Texas and the U.S. over a 24-year period, as well as determining whether alcohol dependence or abuse correlates with mortality rates. ^ Methods. The Spatial Scan Statistic was used to identify regions of excess liver cancer mortality in Texas counties and the U.S. from 1980 to 2003. The statistic was conducted with a spatial cluster size of 50% of the population at risk, and all analyses used publicly available data. Alcohol abuse data by state and ethnicity were extracted from SAMHSA datasets for the study period 2000–2004. ^ Results. The results of the geographic analysis of liver cancer mortality in both Texas and the U.S. indicate that there were four and seven regions, respectively, that were identified as having statistically significant excess mortality rates with elevated relative risks ranging from 1.38–2.07 and 1.05–1.623 (p = 0.001), respectively. ^ Conclusion. This study revealed seven regions of excess mortality of liver cancer mortality across the U.S. and four regions of excess mortality in Texas between 1980–2003, as well as demonstrated a correlation between elevated liver cancer mortality rates and reporting of alcohol dependence among Hispanics and Other populations. ^

Validation of an instrument for assessing the medicolegal death investigation system: A public health approach

Background. This study validated the content of an instrument designed to assess the performance of the medicolegal death investigation system. The instrument was modified from Version 2.0 of the Local Public Health System Performance Assessment Instrument (CDC) and is based on the 10 Essential Public Health Services. ^ Aims. The aims were to employ a cognitive testing process to interview a randomized sample of medicolegal death investigation office leaders, qualitatively describe the results, and revise the instrument accordingly. ^ Methods. A cognitive testing process was used to validate the survey instrument's content in terms of the how well participants could respond to and interpret the questions. Twelve randomly selected medicolegal death investigation chiefs (or equivalent) that represented the seven types of medicolegal death investigation systems and six different state mandates were interviewed by telephone. The respondents also were representative of the educational diversity within medicolegal death investigation leadership. Based on respondent comments, themes were identified that permitted improvement of the instrument toward collecting valid and reliable information when ultimately used in a field survey format. ^ Results. Responses were coded and classified, which permitted the identification of themes related to Comprehension/Interpretation, Retrieval, Estimate/Judgment, and Response. The majority of respondent comments related to Comprehension/Interpretation of the questions. Respondents identified 67 questions and 6 section explanations that merited rephrasing, adding, or deleting examples or words. In addition, five questions were added based on respondent comments. ^ Conclusion. The content of the instrument was validated by cognitive testing method design. The respondents agreed that the instrument would be a useful and relevant tool for assessing system performance. ^

2-methylthio-N$\sp6$-dimethylallyl modification of adenosine 37 of tRNAs in {\it Escherichia coli\/} K-12

The hypermodified, hydrophobic 2-methylthio-N$\sp6$-(dimethylallyl)-adenosine (ms${2{\cdot}6}\atop1$A) residue occurs $3\sp\prime$ to the anticodon in tRNA species that read codons beginning with U. The first step (i$\sp6$A37 formation) of this modification is catalyzed by dimethylallyl diphosphate:tRNA dimethyallyltransferase (EC 2.5.1.8), which is the product of the miaA gene. Subsequent steps were proposed to be catalyzed by MiaB and MiaC enzymes to complete the ms${2{\cdot}6}\atop1$A37 modification. The study of functions of the ms${2{\cdot}6}\atop1$A37 is very important because this modified base is one of the best candidates for a role in global control in response to environmental stress. This dissertation describes the further delineation of functions of the ms${2{\cdot}6}\atop1$A37 modification in E. coli K-12 cells. This work provides significant information on functions of tRNA modifications in E. coli cells to adapt to stressful environmental conditions. Three hypotheses were tested in this work.^ The first hypothesis tested was that non-optimal translation processes cause increased spontaneous mutagenesis by the induction of SOS response in starving cells. To test this hypothesis, I measured spontaneous mutation rates of wild type cells and various mutant strains which are defective in tRNA modification, SOS response, or oxidative damage repair. I found that the miaA mutation acts as a mutator that increased Lac$\sp+$ reversion rates and Trp$\sp+$ reversion frequencies of the wild-type cells in starving conditions. However, the lexA3(Ind)(which abolishes the induction of SOS response) mutation abolished the mutator phenotype of the miaA mutant. The recA430 mutation, not other identified SOS genes, decreased the Lac$\sp+$ reversion to a less extent than that of the lexA3(Ind) mutation. These results suggest that RecA together with another unidentified SOS gene product are responsible for the process.^ The second hypothesis tested was that MiaA protein binds to full-length tRNA$\sp{\rm Phe}$ molecules in form of a protein dimer. To test this hypothesis, three versions of the MiaA protein and seven species of tRNA substrates were purified. Binding studies by gel mobility shift assays, filter binding assays and gel filtration shift assays support the hypothesis that MiaA protein binds to full-length tRNA$\sp{\rm Phe}$ as a protein dimer but as a monomer to the anticodon stem-and-loop. These results were further supported by using steady state enzyme kinetic studies.^ The third hypothesis tested in this work was that the miaB gene in E. coli exists and is clonable. The miaB::Tn10dCm insertion mutation of Salmonella typhimurium was transduced to E. coli K-12 cells by using P$\sb1$ and P$\sb{22}$ bacteriophages. The insertion was confirmed by HPLC analyses of nucleotide profiles of miaB mutants of E. coli. The insertion mutation was cloned and DNA sequences adjacent to the transposon were sequenced. These DNA sequences were 86% identical to the f474 gene at 14.97 min chromosome of E. coli. The f474 gene was then cloned by PCR from the wild-type chromosome of E. coli. The recombinant plasmid complemented the mutant phenotype of the miaB mutant of E. coli. These results support the hypothesis that the miaB gene of E. coli exists and is clonable. In summary, functions of the ms${2{\cdot}6}\atop1$A37 modification in E. coli cells are further delineated in this work in perspectives of adaptation to stressful environmental conditions and protein:tRNA interaction. (Abstract shortened by UMI.) ^