Stabilization of troponin I for applications in clinical chemistry and forensic medicine. Cardiac troponin I: A time of death marker

Cardiac troponin I (cTnI) is one of the most useful serum marker test for the determination of myocardial infarction (MI). The first commercial assay of cTnI was released for medical use in the United States and Europe in 1995. It is useful in determining if the source of chest pains, whose etiology may be unknown, is cardiac related. Cardiac TnI is released into the bloodstream following myocardial necrosis (cardiac cell death) as a result of an infarct (heart attack). In this research project the utility of cardiac troponin I as a potential marker for the determination of time of death is investigated. The approach of this research is not to investigate cTnI degradation in serum/plasma, but to investigate the proteolytic breakdown of this protein in heart tissue postmortem. If our hypothesis is correct, cTnI might show a distinctive temporal degradation profile after death. This temporal profile may have potential as a time of death marker in forensic medicine. The field of time of death markers has lagged behind the great advances in technology since the late 1850's. Today medical examiners are using rudimentary time of death markers that offer limited reliability in the medico-legal arena. Cardiac TnI must be stabilized in order to avoid further degradation by proteases in the extraction process. Chemically derivatized magnetic microparticles were covalently linked to anti-cTnI monoclonal antibodies. A charge capture approach was also used to eliminate the antibody from the magnetic microparticles given the negative charge on the microparticles. The magnetic microparticles were used to extract cTnI from heart tissue homogenate for further bio-analysis. Cardiac TnI was eluted from the beads with a buffer and analyzed. This technique exploits banding pattern on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by a western blot transfer to polyvinylidene fluoride (PVDF) paper for probing with anti-cTnI monoclonal antibodies. Bovine hearts were used as a model to establish the relationship of time of death and concentration/band-pattern given its homology to human cardiac TnI. The final concept feasibility was tested with human heart samples from cadavers with known time of death. ^

Parent involvement on school advisory councils: A process evaluation at the middle school level

Increasing parental involvement was made an important goal for all Florida schools in educational reform legislation in the 1990's. A forum for this input was established and became known as the School Advisory Council (SAC). To demonstrate the importance of process and inclusion, a south Florida school district and its local teacher's union agreed on the following five goals for SACs: (a) to foster an environment of professional collaboration among all stakeholders, (b) to assist in the preparation and evaluation of the school improvement plan, (c) to address all state and district goals, (d) to serve as the avenue for authentic and representative input from all stakeholders, and (e) to ensure the continued existence of the consensus-building process on all issues related to the school's instructional program. ^ The purpose of this study was to determine to what extent and in what ways the parent members of one south Florida middle school's SAC achieved the five district goals during its first three years of implementation. The primary participants were 16 parents who served as members of the SAC, while 16 non-parent members provided perspective on parent involvement as “outside sources.” Being qualitative by design, factors such as school climate, leadership styles, and the quality of parental input were described from data collected from four sources: parent interviews, a questionnaire of non-parents, researcher observations, and relevant documents. A cross-case analysis of all data informed a process evaluation that described the similarities and differences of intended and observed outcomes of parent involvement from each source using Stake's descriptive matrix model. A formative evaluation of the process compared the observed outcomes with standards set for successful SACs, such as the district's five goals. ^ The findings indicated that parents elected to the SACs did not meet the intended goals set by the state and district. The school leadership did not foster an environment of professional collaboration and authentic decision-making for parents and other stakeholders. The overall process did not include consensus-building, and there was little if any input by parents on school improvement and other important issues relating to the instructional program. Only two parents gave the SAC a successful rating for involving parents in the decision-making process. Although compliance was met in many of the procedural transactions of the SAC, the reactions of parents to their perceived role and influence often reflected feelings of powerlessness and frustration with a process that many thought lacked meaningfulness and productivity. Two conclusions made from this study are as follows: (a) that the role of the principal in the collaborative process is pivotal, and (b) that the normative-re-educative approach to change would be most appropriate for SACs. ^

The significance of chloroplast movement in leaves of tropical plants

The purpose of this research project was to contribute to the understanding of chloroplast movement in plants. Chloroplast movement in leaves from twenty tropical plant species ranging from cycads to monocots and varying in shade tolerance was examined by measuring changes in transmittance following 30 min. of exposure to white light at 1000 μmol m−2 s −1 in the wavelength range of 400–700 nm (photosynthetically active radiation, PAR). Leaf anatomical characteristics were also measured. Eighteen species increased significantly in transmittance (Δ T) at this level of illumination. ^ Chloroplast movement was significantly correlated with palisade cell width suggesting that cell dimensions are a significant constraint on chloroplast movement in the species examined. In addition, Δ T values were strongly correlated with values of an index of shade tolerance. ^ To further examine the relationship between palisade width and chloroplast movement, additional studies were conducted with a tropical aroid vine, Scindapsus aureus Schott. Scindapsus plants were grown under three different light treatments: 63% (control), 9.0% and 2.7% of full sunlight. Under these growing conditions plants produced markedly different palisade cell widths. Palisade cell width was again found to be correlated with transmittance changes. In addition, the observed increases in transmittance following exposure to the above illumination condition were correlated with absorbance of PAR. Fluorescence studies demonstrated that chloroplast movement helps protect Scindapsus aureus from the effects of photoinhibition when it is exposed to light at a higher intensity relative to the intensity of its normal environment. Ratios of variable fluorescence (Fv) to maximal fluorescence (Fm ) were higher in plants exposed to high light when chloroplasts moved than in plants where chloroplasts did not. ^ To further explore the role of chloroplast movement, studies were conducted to determine if transmittance changes could be induced in ten xerophytes at (1000 μmol m−2 s−1), as well as two stronger light intensities (1800 μmol m−2 s−1 and 2200 μmol m−2 s −1). Transmittance changes in the ten xerophytes were dependent upon the illumination intensity; nine out of the ten xerophytes changed in transmittance at 1800 μmol m−2 s−1. For the other two intensity levels, only three out of the ten xerophytes tested exhibited transmittance changes, and for two species, a negative Δ T value was obtained at 1000 μmol m−2 s−1 . No relationship was found between cell dimensions and chloroplast movement, although all species had large enough chlorenchyma cells to allow such movements. ^ The results of the study clearly show that in non-xerophytes, palisade cell anatomy is a strong constraint on chloroplast movement. This relationship may be the basis for the relationship between chloroplast movement and shade tolerance. Although absorbance changes are relatively small, chloroplast movement was clearly shown to reduce photoinhibition. ^

Teacher talk: A community of colleagues that values practical teacher knowledge through sharing experiences

The purpose of this study was to describe the experiences of five educators participating in a teacher-initiated learning community that valued practical teacher knowledge. Connelly and Clandinin (2000) argued that practical teacher knowledge grew out of experience through interaction in the professional knowledge landscape. Collaboration that promoted teacher learning was the foundation to effective school change (Wood, 1997). This teacher-initiated learning community consisted of members who had equal status and collaborated by participating in discourse on curriculum and instruction. The collegiality of the community fostered teacher professionalism that improved practice and benefited the school. This study focused on the following research questions: (1) What was the experience of these five educators in this learning community? (2) What did these five individuals understand about the nature of practical teacher knowledge? (3) According to the participants, what was the relationship between teacher empowerment and effective school change? ^ The participants were chosen because each voluntarily attended this teacher-initiated learning community. Each participant answered questions regarding the experience during three semi-structured tape-recorded interviews. The interviews were transcribed, and significant statements of meaning were extracted. Using a triangulation of ideas that were common to at least three of the participants ensured the trustworthiness of the analysis. These statements were combined to describe what was experienced and how the participants described their experience. The emerging themes were the characteristics of and the relationships, methods, conditions, and environment for the teachers. The teachers described how a knowledge base of practical teacher knowledge was gained as a spirit of camaraderie developed. The freedom that the teachers experienced to collaborate and learn fostered new classroom practice that affected school change as student interaction and productivity increased. ^ The qualitative analysis of this study provided a description of a learning community that valued practical teacher knowledge and fostered professional development. This description was important to educational stakeholders because it demonstrated how practical teacher knowledge was gained during the teachers' daily work. By sharing every day experiences, the teacher talk generated collaboration and accountability that the participants felt improved practice and fostered a safe, productive learning environment for students. ^

Heteronormativity and teaching: A phenomenological study of lesbian teachers

The purpose of this phenomenological study was to understand what impact “heteronormativity” has on a lesbian teacher's perception of her instructional style, content, and context of curriculum taught. Through taped interviews with lesbian educators, this research examined the lived experience of the lesbian teacher. The framework for this study included theories related to historical, sociocultural, and psychosocial development while the methodology included a qualitative design using primary elements of a phenomenological study outlined without ignoring the influence associated with contextualism. Due to the sensitive nature of the study nine women who were the focus of this research were volunteers with the first serving as a “gatekeeper” to assist in the pilot study. The subsequent group evolved as a result of “snowballing” to gain more participants. ^ The data in the form of narrative derived from the interviews was transcribed, color-coded, and organized into four themes and associated sub-themes, based upon the perceptions of these educators. These themes characterized the coming out process of a lesbian, which directly paralleled the personal and professional development of the lesbian educator, emerged as a result of the analysis. They included: (a) self-acknowledgement; (b) self-indentification; (c) coming out to other lesbians by overcoming fear and establishing relationships; (d) coming out to others by overcoming heteronormativity by using support groups in defining a lesbian's role as a teacher. ^ The results of this study showed that the acceptance of the lesbian culture, shared with the acknowledgement, rather than compliance or defiance, of cultural hegemony can allow the lesbian educator to develop a curriculum and a classroom climate that will foster understanding and even generate social change among colleagues, parents, and students, one person at a time. ^

Special education teachers' perspectives on teaching middle school students with severe emotional disturbance

The voices of special education teachers who educate middle school students with severe emotional disturbance (SED) have been largely unheard in the educational forum and in the discussion about raising the academic achievement of middle school students with SED. These students continue to have high attrition rates and low levels of academic achievement. This study described and analyzed the perspectives of five special education teachers regarding appropriate instructional strategies for educating middle school students with SED. It also explored these teachers' opinions concerning difficulties they experienced in raising the academic achievement of students with SED and some of the solutions for overcoming these challenges. The professional literature emphasizes the importance of teacher knowledge (Altrichter, Posch, & Somekh, 1996; Clandinin & Connelly, 1996) and also offers suggestions for appropriate instructional strategies for educating students with SED (Bauer, Keefe, & Shea, 2002; Heward, 2000; Kauffman, 2001; Polloway, Patton, & Serna 2001). ^ A qualitative case study was employed to describe and analyze the five participants' perspectives on teaching middle school students with SED. The sources of data collection were interviews, observations and analysis of documents. Data presentation was from the perspective of the participants in dialogue with the interpretations of the researcher and against the backdrop of the professional literature and the researcher's critical theory philosophy. One of the major themes that emerged from the analysis was the teachers' insistence on the students' need for discipline tempered with teacher nurturing and playfulness. One concern was the need for teacher training in current appropriate, research-based instructional strategies for educating students with SED. ^ As a result of this study, one of the recommendations made was for more rigorous standards of re-certification and professional development of certified teachers who educate students with SED. ^

The effectiveness of training educators on their ability to identify function of problem behavior

The purpose of this study was to investigate the effectiveness of training educators in the pre-behavioral intervention process of functional behavioral assessment. An original evaluation instrument was developed entitled, The Survey for Students Exhibiting Challenging Behavior. The instrument included measures of participating educators, knowledge of function of problem behavior and their ability to generate recommendations for a behavior intervention plan. The instrument was distributed to schools in a large urban district and completed by special educators. Educators trained and untrained in the functional behavioral assessment process were compared in the study. ^ The study incorporated a post-test only design. All instruments were analyzed using a factorial ANOVA. Those educators who were trained in the district functional behavioral assessment program answered general questions related to function of problem behavior significantly better than those who did not receive training. There is no significant difference between educators on their ability to generate recommendations for behavior intervention plans. It is important that educators receive training in functional behavioral assessment to gain an understanding of the basic notions being function of problem behavior. Current training does not translate into educators' ability to make strong recommendations for behavior intervention plans. ^

Vegetation dynamics and their implications for the management of wetlands in the lowlands of Nepal

The maintenance of species richness is often a priority in the management of nature reserves, where consumptive use of resources is generally prohibited. The purpose of this research was to improve management by understanding the vegetation dynamics in the lowlands of Nepal. The objectives were to determine vegetation associations in relation to environments and human-induced disturbances that affect vegetation dynamics on floodplains, where upstream barrages had altered flooding patterns, and consumptive use of plant resources was influencing natural processes. Floodplain vegetation in relation to physical environments and disturbances were studied along transects, perpendicular to the course of the Mahakali River in the western Terai, Nepal. Forest structural changes were studied for three years in ten plots. A randomized split-block experiment with nine burning and grazing treatments was performed in seasonally flooded grasslands. A semi-structured questionnaire was used to assess people's socio-economic status, natural resource use patterns and conservation attitudes. ^ Elevation, soil organic matter, nitrogen, percentage of sand and grazing intensity were significant in delineating herbaceous vegetation assemblages, whereas elevation and livestock grazing were significant in defining forest type boundaries. On the floodplain islands, highly grazed Dalbergia sissoo-Acacia catechu forests were devoid of understory woody vegetation, but the lightly grazed D. sissoo-mixed forests had a well-developed second canopy layer, comprising woody species other than D. sissoo and A. catechu. In grasslands, species richness and biomass production were highest at intermediate disturbance level represented by the lightly grazed and ungrazed early-burned treatments. Ethnicity, education and resource use patterns were important in influencing conservation attitudes. A succession towards the mixed forests would occur in D. sissoo-dominated floodplain forests, where dams and barrages reduce flooding and associated fluvial processes, and if livestock grazing is stopped, as occasionally suggested by nature conservationists. In seasonally flooded grasslands, early burning with moderate grazing would enhance the species diversity and productivity. There is a need to implement a participatory integrated wetland management plan, to include community development, education and off farm income generation, to assure participatory conservation and management of wetlands in Nepal. ^

The effects of a family-based educational intervention on the prevention of lead poisoning in children

The effects of lead exposure may endure through one's lifetime and can negatively effect educational performance. While the link between the cause and effects of lead poisoning has been identified, the application of lead health education as the mechanism of disease prevention has not. The purpose of this study was to examine whether caregiver participation in a family-based educational intervention can result in decreased lead exposure in low socioeconomic children. ^ Participants (n = 50) were caregivers of children 12 to 36 months of age. They were randomly selected from an urban clinic and randomly assigned to either a treatment or control group. The experimental design of this study involved two clinic visits. Parents in the treatment group were given the educational intervention during the first clinic visit while those in the control group were given the intervention during the second clinic visit. The intervention was reinforced with a lead education brochure coupled with a video on childhood lead poisoning. One instrument was used to test parental knowledge of lead poisoning both pre- and post-intervention. Blood lead levels in pediatric participants were tested using two blood lead screens approximately three to four months apart determined by well-child check-up schedules. ^ Findings from the analysis of variance showed the interaction between the change in blood lead level between the children's first and second clinic visits and the treatment level. This demonstrated a significant interaction between the differences of first and second clinic visits blood lead levels and the presence or absence of the educational intervention. ^ The findings from an analysis of covariance support that caregivers in the treatment group have significantly higher scores on the second clinic visit scores on the CLKT than the caregivers in the control group. These data suggest that the educational treatment is effective in increasing the knowledge of caregivers about the dangers of lead poisoning and the strategies for lead poisoning prevention. ^ Conclusions indicate that the education of adult caregivers can affect blood lead levels of children, the educational treatment increased the knowledge of caregivers, caregivers were able to carry out procedures taught, and caregivers retained knowledge over time. ^

Social support, risk, and adjustment of immigrant preadolescents

The current study was designed to explore the salience of social support, immigrant status, and risk in middle childhood and early adolescence across two time periods as indicated by measures of school adjustment and well-being. Participants included 691 children of public elementary schools in grades 4 and 6 who were interviewed in 1997 (Time 1) and reinterviewed two years later (Time 2); 539 were U.S.-born, and 152 were foreign-born. ^ Repeated measures multivariate analyses of variance (MANOVA's) were conducted to assess the effects of immigrant status and risk on total support, well-being, and school adjustment from Time 1 to Time 2. Follow-up analyses, including Student-Newman-Keuls post hoc tests, were used to test the significance of the differences among the means of support categories (low and high), immigrant status (U.S. born and non-U.S. born), risk (low and high) and time (time 1 and time 2). ^ Results showed that immigrant participants in the high risk group reported significantly lower levels of support than their peers. Further, children of low risk at Time 2 indicated the highest levels of support. Second, immigrant preadolescents, preadolescents who reported low levels of social support, and preadolescents of the high risk reported lower levels of emotional well-being. There was also an interaction of support by risk by time, indicating that children who are at risk and had low levels of social support reported more emotional problems at Time 1. Finally, preadolescents who are at risk and preadolescents who reported lower levels of support were more likely to show school adaptation problems. Findings from this study highlight the importance of a multivariable approach to the study of support, emotional adjustment, and academic adjustment of immigrant preadolescents. ^

Gender across cultures: The immigration experience/Bulgarian immigrants in South Florida

During the last decade, the United States has witnessed a high increase in its immigration flow. Despite recent surge of interest in numerically small ethnic groups, data on Bulgarian immigrants in the United States is almost non-existent. This is the first comprehensive study on the Bulgarian ethnic group in the United States. ^ This study examined the impact of immigration upon the negotiation of cultural prescriptions by Bulgarian immigrants in the United States. Several fundamental Bulgarian prescriptions for daily behavior, such as emphasis on stability rather than mobility, preference for collectivism instead of individualism, and wide use of social critique rather than social approval were tested on U.S. soil. Furthermore, the impact of gender upon cultural appropriation and retention was considered. The study made use of a comprehensive historical analysis of Bulgarian immigration to the United States, statistical descriptions of contemporary Bulgarian immigrants in the United States, and over a three-year long qualitative study of Bulgarian immigrants in South Florida. ^ The results of the study indicated that the transferring of cultural prescriptions due to immigration did not occur unaffected by gender. Bulgarian and U.S. cultural models clashed, intermingled, and resisted each other in various ways depending on the immigrants' gender. At the same time, gender did not solely determine the validity of prescriptions for daily behavior, but it rather acted in concert with other principles of everyday life. In addition, gender impacted significantly the method, type, and structure of the immigration journey. Gender was a very significant variable in the determination of these features of the immigration process, but it did not account independently for historical variations. Other factors, such as larger contexts of reception and rejection also played an important role. ^