15 resultados para Method development

em Brock University, Canada


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A high performance liquid chromatographic method employing two columns connected in series and separated~y·a.switching valve has been developed for the analysis of the insecticide/ nematicide oxamyl (methyl-N' ,N'-dimethyl-N-[(methylcarbamoyl) oxy]-l-thiooxarnimidate) and two of its metabolites. A variation of this method involving two reverse phase columns was employed to monitor the persistence and translocation of oxamyl in treated peach seedlings. It was possible to simultaneously analyse for oxamyl and its corresponding oxime (methyl-N',N'-dimethyl-N-hydroxy-l-thiooxamimidate}, a major metabolite of oxamyl in plants, without prior cleanup of the samples. The method allowed detection of 0.058 pg oxamyl and 0.035 p.g oxime. On treated peach leaves oxamyl was found to dissipate rapidly during the first two-week period, followed by a period of slow decomposition. Movement of oxamyl or its oxime did not occur in detectable quantities to untreated leaves or to the root or soil. A second variation of the method which employed a size exclusion column as·the first column and a reverse phase column as the second was used to monitor the degradation of oxamyl in treated, planted corn seeds and was suitable for simultaneous analysis of oxamyl, its oxime and dimethylcyanoformamide (DMCF), a metabolite of oxamyl. The method allowed detection of 0.02 pg oxamyl, 0.02 p.g oxime and 0.005 pg DMCF. Oxamyl was found to persist for a period of 5 - 6 weeks, which is long enough to permit oxamyl seedtreatment to be considered as a potential means of protecting young corn plants from nematode attack. Decomposition was found to be more rapid in unsterilized soil than in sterililized soil. DMCF was found to have a nematostatic effect at high concentrations ( 2,OOOpprn), but at lower concentrations no effect on nematode mobility was observed. Oxamyl, on the other hand, was found to reduce the mobility of nematodes at concentrations down to 4 ppm.

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Part I: Ultra-trace determination of vanadium in lake sediments: a performance comparison using O2, N20, and NH3 as reaction gases in ICP-DRC-MS Thermal ion-molecule reactions, targeting removal of specific spectroscopic interference problems, have become a powerful tool for method development in quadrupole based inductively coupled plasma mass spectrometry (ICP-MS) applications. A study was conducted to develop an accurate method for the determination of vanadium in lake sediment samples by ICP-MS, coupled with a dynamic reaction cell (DRC), using two differenvchemical resolution strategies: a) direct removal of interfering C10+ and b) vanadium oxidation to VO+. The performance of three reaction gases that are suitable for handling vanadium interference in the dynamic reaction cell was systematically studied and evaluated: ammonia for C10+ removal and oxygen and nitrous oxide for oxidation. Although it was able to produce comparable results for vanadium to those using oxygen and nitrous oxide, NH3 did not completely eliminate a matrix effect, caused by the presence of chloride, and required large scale dilutions (and a concomitant increase in variance) when the sample and/or the digestion medium contained large amounts of chloride. Among the three candidate reaction gases at their optimized Eonditions, creation of VO+ with oxygen gas delivered the best analyte sensitivity and the lowest detection limit (2.7 ng L-1). Vanadium results obtained from fourteen lake sediment samples and a certified reference material (CRM031-040-1), using two different analytelinterference separation strategies, suggested that the vanadium mono-oxidation offers advantageous performance over the conventional method using NH3 for ultra-trace vanadium determination by ICP-DRC-MS and can be readily employed in relevant environmental chemistry applications that deal with ultra-trace contaminants.Part II: Validation of a modified oxidation approach for the quantification of total arsenic and selenium in complex environmental matrices Spectroscopic interference problems of arsenic and selenium in ICP-MS practices were investigated in detail. Preliminary literature review suggested that oxygen could serve as an effective candidate reaction gas for analysis of the two elements in dynamic reaction cell coupled ICP-MS. An accurate method was developed for the determination of As and Se in complex environmental samples, based on a series of modifications on an oxidation approach for As and Se previously reported. Rhodium was used as internal standard in this study to help minimize non-spectral interferences such as instrumental drift. Using an oxygen gas flow slightly higher than 0.5 mL min-I, arsenic is converted to 75 AS160+ ion in an efficient manner whereas a potentially interfering ion, 91Zr+, is completely removed. Instead of using the most abundant Se isotope, 80Se, selenium was determined by a second most abundant isotope, 78Se, in the form of 78Se160. Upon careful selection of oxygen gas flow rate and optimization ofRPq value, previous isobaric threats caused by Zr and Mo were reduced to background levels whereas another potential atomic isobar, 96Ru+, became completely harmless to the new selenium analyte. The new method underwent a strict validation procedure where the recovery of a suitable certified reference material was examined and the obtained sample data were compared with those produced by a credible external laboratory who analyzed the same set of samples using a standardized HG-ICP-AES method. The validation results were satisfactory. The resultant limits of detection for arsenic and selenium were 5 ng L-1 and 60 ng L-1, respectively.

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The purpose of this study was to explore elementary educators’ knowledge of moral development, how this knowledge relates to their beliefs and sense of efficacy pertaining to character education practices and the socio-moral reasoning of their students. It was hypothesized that educators’ beliefs and practices related to character education would reflect their pedagogy rather than knowledge of moral development theory. It was further hypothesized that there would be differences in student socio-moral reasoning specifically the beliefs and desires that guide actions would differ based on grade and gender. This mixed-method study employing self-report questionnaires, open response vignettes, and semi-structured educator interviews yielded quantitative and qualitative data. Findings indicated socio-moral reasoning of students differed according to grade (age) and gender. Knowledge of moral development theory was found to vary among participants however some practices employed by educators did align with a social cognitive approach to moral development. Significant variables identified consistently among educator and student participants included, autonomy, social competence, sense of school community, and supportiveness. These variables, in conjunction with a sense of fairness, have been identified elsewhere as foundational to moral development (Nucci, 2009), and intrinsic motivation (Ryan & Deci, 2000) and are relevant to educators working to develop student socio-moral reasoning as an aspect of character.

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National governments, the United Nations, and other organizations have deemed sport and other means of physical activity such as recreation, games and play for development a useful means for addressing a wide range of problems in communities and more specifically, providing youth with an opportunity to experience the benefits of physical activity. There is a need for research that furthers our understanding of how participants experience these programs. Specifically, the purpose of this study, was to better understand the lived experiences of the participants in a YMCA camp program that integrated physical activity and play for the specific development of poor youth street workers. A phenomenological approach infonned by a critical perspective (Creswell, 2003; Rossman & Rallis, 2003) was used. The study took place through the Asociaci6n Cristiana de J6venes de Costa Rica (ACJ) in Central America. The focus was on a camp program and the lived experiences of six purposefully chosen, youth street workers between the ages of 13-17. Their experiences were explored through semi-structured interviews. Other data that fonn the study include: field notes, observations, a reflexive journal and document analysis. The findings that emerged from the data include main themes of relationships, poverty, personal change and empowennent. For many youth, the ACJ is a relatively safe place to play, to "detach," their minds, to "distract" and "disorient" themselves from their dysfunctional families, violent neighbourhood, the poverty they live in, and from the necessity of having to work in the street to supplement the family income. Although many studies have shown that programs that include physical activity, play and/or sport have a positive impact on youth with regard to healthy development and improvements in well-being, there has been little work done to address the voices and experiences of the youth that participate in these programs. Using an interpretive-critical approach, this study focused on the participants' personal backgrounds, their experiences within the program and their critical reflections on the program. This study draws from a phenomenological philosophy and method to report findings from participants in an ACJ program in Costa Rica. This research shows how these youth were given the opportunity to use the program and the ACJ property as a relatively safe place to play, to behave like the youth they are, to establish and maintain their friendship networks, and develop empathy and conflict resolution skills. The fmdings from this study reveal how by participating in the ACJ program they each described a personal change, wherein they felt empowered to learn they could positivel y control themselves and as a result positively affect their own futures. These fmdings contribute knowledge surrounding the lived experiences of youth in developmental programs that use physical activity.

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Rapid and large accumulation of GABA (y-aminobutyric acid) in response to a number of plant stresses has been well documented. But the role(s) of GABA in plants is not well defined. In recent years, the possibility of GABA involvement in regulating plant growth and development has been raised. In the present study, this possibility was examined. First, to rapidly and accurately determine GABA levels in plant tissues, a spectrometric method for GABA determination was developed based on a commercially available enzyme Gabase. Seventy mM LaCb almost completely removed water-soluble pigments from plant tissues which greatly interfere with the absorbance reading at 340nm. Inactivation of GAD (glutamate decarboxylase) by immediately adding methanol to a frozen plant tissue powder was suggested to prevent GABA production during extraction. The recovery of GABA with this method was approximately 100%. Second, the relationship between GABA levels and hypocotyl elongation in soybean seedlings was analyzed using different approaches to regulate in vivo GABA levels and the elongation of hypocotyls. The following major observations were made. (1) Mechanical stimulation by stroking elevated GABA levels and concurrently induced a rapid and significant reduction in hypocotyl elongation. (2) External GABA was demonstrated to penetrate into the hypocotyls using '*C-GABA. Application of external GABA elevated in vivo GABA levels, but failed to inhibit hypocotyl elongation. (3) LaCla and blue light irradiation caused an inhibition in the elongation of dark-grown hypocotyls, whereas GABA levels were not significantly affected. (4) Ca^was suggested to be involved in the signal transduction pathway leading from mechanical stimulation to GABA production, as indicated by the ability of La'* to inhibit GABA production in stimulated hypocotyls. (5) Bicuculline, saclofen and baclofen (agonists and antagonists of GABA receptors in animals) had no effect on hypocotyl elongation. It might indicate that GABA-binding components which are structurally similar to animal GABA receptors and functionally capable of regulating plant growth may not exist in plants. Therefore, the conclusion was drawn that GABA alone is not sufficient to inhibit hypocotyl elongation. Third, chloride influx in isolated Asparagus cells was enhanced by lOmM GABA during a 3 hour incubation, but the effect was not specific for GABA. Chloride efflux was not influenced by GABA. Both influx and efflux of chloride were significantly inhibited by NPPB, a chloride channel blocker. These results suggest that GABA does not influence the activity of plant chloride channels.

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Career identity exploration is a central component of the lives of undergraduate university students. Although students are encouraged to explore, it is unclear whether different methods of exploration are better suited for certain individuals. In the present study, quantitative data were collected to examine the relationship between shyness and various methods of exploration. Two hundred fifty-seven university undergraduate students (29 male), ranging in age from 17-25 years completed a 60-minute self-report questionnaire. Shyness, identity, identity distress, subjective dimensions of exploration (satisfaction with exploration, reasons for not exploring, helpfulness of exploration methods), foci of exploration (non-social, social, self, and environmental), approaches to exploration (breadth, depth), and moderating variables (social support, sociability) were measured. Shyness was positively correlated with moratorium (high exploration, low commitment) and uncorrelated with the other identity statuses. Shyness was also positively correlated with identity distress, and a predicted interaction between shyness and identity diffusion predicting career identity distress was supported. Shyness was negatively correlated with satisfaction with amount of exploration engaged in to-date. In addition, shyness was correlated with the likelihood of selecting too stressful and too anxiety provoking as reasons for engaging in less exploration than one would like. Expected relationships between shyness and beliefs about, and engagement in, various methods of exploration were largely non-significant. Exceptions to this were the negative correlations between shyness and engagement in social exploration, and beliefs about the helpfulness of social self-exploration, both of which were significant at a trend level. A predicted interaction between shyness and social support predicting total social exploration was supported, showing that high social support buffers the negative relationship between shyness and exploration; such a moderating relationship did not exist, however, between sociability, shyness and social exploration. Results suggest that although shy university students are engaged in career exploration, they are experiencing feelings of distress and dissatisfaction with their career identity exploration and development. Thus, to help shy students become successfiil in their exploration, it is important for counsellors, family members, and peers to be aware of the feelings the individuals are experiencing and help them reduce the anxiety and stress associated with the exploration process. One promising method, supported by the results in this study, is by encouraging shy individuals to explore with social support.

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The phenomenon of communitas has been described as a moment 'in and out of time' in which a collective of individuals may be experienced by one as equal and individuated in an environment stripped of structural attributes (Turner, 1 969). In these moments, emotional bonds form and an experience of perceived 'oneness' and synergy may be described. As a result of the perceived value of these experiences, it has been suggested by Sharpe (2005) that more clearly understanding how this phenomenon may be purposefully facilitated would be beneficial for leisure service providers. Consequently, the purpose of this research endeavor was to examine the ways in which a particular leisure service provider systematically employs specific methods and sets specific parameters with the intention of guiding participants toward experiences associated with communitas or "shared spirit" as described by the organization. A qualitative case study taking a phenomenological approach was employed in order to capture the depth and complexity of both the phenomenon and the purposefiil negotiation of experiences in guiding participants toward this phenomenon. The means through which these experiences were intentionally facilitated was recreational music making in a group drumming context. As such, an organization which employs specific methods of rhythm circle facilitation as well as trains other facilitators all over the world was chosen purposely for their recognition as the most respectable and credible in this field. The specific facilitator was chosen based on high recommendation by the organization due to her level of experience and expertise. Two rhythm circles were held, and participants were chosen randomly by the facilitator. Data was collected through observation in the first circle and participant- observation in the second, as well as through focus groups with circle participants. Interviews with the facilitator were held both initially to gain broad understanding of concepts and phenomenon as well as after each circle to reflect on each circle specifically. Data was read repeatedly to drawn out patterns which emerged and were coded and organized accordingly. It was found that this specific process or system of implementation lead to experiences associated with communitas by participants. In order to more clearly understand this process and the ways in which experiences associated with communitas manifest as a result of deliberate facilitator actions, these objective facilitator actions were plotted along a continuum relating to subjective participant experiences. These findings were then linked to the literature with regards to specific characteristics of communitas. In so doing, the intentional manifestation of these experiences may be more clearly understood for ftiture facilitators in many contexts. Beyond this, findings summarized important considerations with regards to specific technical and communication competencies which were found to be essential to fostering these experiences for participants within each group. Findings surrounding the maintenance of a fluid negotiation of certain transition points within a group rhythm event overall were also highlighted, and this fluidity was found to be essential to the experience of absorption and engagement in the activity and experience. Emergent themes of structure, control, and consciousness have been presented as they manifested and were found to affect experiences within this study. Discussions surrounding the ethics and authenticity of these particular methods and their implementation has also been generated throughout. In conclusion, there was a breadth as well as depth of knowledge found in unpacking this complex process of guiding individuals toward experiences associated with communitas. The implications of these findings contribute in broadening the current theoretical as well as practical understanding as to how certain intentional parameters may be set and methods employed which may lead to experiences of communitas, and as well contribute a greater knowledge to conceptualizing the manifestation of these experiences when broken down.

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Adenoviral vectors are currently the most widely used gene therapeutic vectors, but their inability to integrate into host chromosomal DNA shortened their transgene expression and limited their use in clinical trials. In this project, we initially planned to develop a technique to test the effect of the early region 1 (E1) on adenovirus integration by comparing the integration efficiencies between an E1-deleted adenoviral vector (SubE1) and an Elcontaining vector (SubE3). However, we did not harvest any SubE3 virus, even if we repeated the transfection and successfully rescued the SubE1 virus (2/4 transfections generated viruses) and positive control virus (6/6). The failure of rescuing SubE3 could be caused by the instability of the genomic plasmid pFG173, as it had frequent intemal deletions when we were purifying It. Therefore, we developed techniques to test the effect of E1 on homologous recombination (HR) since literature suggested that adenovirus integration is initiated by HR. We attempted to silence the E1 in 293 cells by transfecting E1A/B-specific small interfering RNA (siRNA). However, no silenced phenotype was observed, even if we varied the concentrations of E1A/B siRNA (from 30 nM to 270 nM) and checked the silencing effects at different time points (48, 72, 96 h). One possible explanation would be that the E1A/B siRNA sequences are not potent enough to Induce the silenced phenotype. For evaluating HR efficiencies, an HR assay system based on bacterial transfonmatJon was designed. We constmcted two plasmids ( designated as pUC19-dl1 and pUC19-dl2) containing different defective lacZa cassettes (forming white colonies after transformation) that can generate a functional lacZa cassette (forming blue colonies) through HR after transfecting into 293 cells. The HR efficiencies would be expressed as the percentages of the blue colonies among all the colonies. Unfortunately, after transfonnation of plasmid isolated from 293 cells, no colony was found, even at a transformation efficiency of 1.8x10^ colonies/pg pUC19, suggesting the sensitivity of this system was low. To enhance the sensitivity, PCR was used. We designed a set of primers that can only amplify the recombinant plasmid fomied through HR. Therefore, the HR efficiencies among different treatments can be evaluated by the amplification results, and this system could be used to test the effect of E1 region on adenovirus integration. In addition, to our knowledge there was no previous studies using PCR/ Realtime PCR to evaluate HR efficiency, so this system also provides a PCR-based method to carry out the HR assays.

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Several automated reversed-phase HPLC methods have been developed to determine trace concentrations of carbamate pesticides (which are of concern in Ontario environmental samples) in water by utilizing two solid sorbent extraction techniques. One of the methods is known as on-line pre-concentration'. This technique involves passing 100 milliliters of sample water through a 3 cm pre-column, packed with 5 micron ODS sorbent, at flow rates varying from 5-10 mUmin. By the use of a valve apparatus, the HPLC system is then switched to a gradient mobile phase program consisting of acetonitrile and water. The analytes, Propoxur, Carbofuran, Carbaryl, Propham, Captan, Chloropropham, Barban, and Butylate, which are pre-concentrated on the pre-column, are eluted and separated on a 25 cm C-8 analytical column and determined by UV absorption at 220 nm. The total analytical time is 60 minutes, and the pre-column can be used repeatedly for the analysis of as many as thirty samples. The method is highly sensitive as 100 percent of the analytes present in the sample can be injected into the HPLC. No breakthrough of any of the analytes was observed and the minimum detectable concentrations range from 10 to 480 ng/L. The developed method is totally automated for the analysis of one sample. When the above mobile phase is modified with a buffer solution, Aminocarb, Benomyl, and its degradation product, MBC, can also be detected along with the above pesticides with baseline resolution for all of the analytes. The method can also be easily modified to determine Benomyl and MBC both as solute and as particulate matter. By using a commercially available solid phase extraction cartridge, in lieu of a pre-column, for the extraction and concentration of analytes, a completely automated method has been developed with the aid of the Waters Millilab Workstation. Sample water is loaded at 10 mL/min through a cartridge and the concentrated analytes are eluted from the sorbent with acetonitrile. The resulting eluate is blown-down under nitrogen, made up to volume with water, and injected into the HPLC. The total analytical time is 90 minutes. Fifty percent of the analytes present in the sample can be injected into the HPLC, and recoveries for the above eight pesticides ranged from 84 to 93 percent. The minimum detectable concentrations range from 20 to 960 ng/L. The developed method is totally automated for the analysis of up to thirty consecutive samples. The method has proven to be applicable to both purer water samples as well as untreated lake water samples.

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Preclinical and clinical tooth important and significant aspect of preparation is an a dental student's education. The associated procedures rely heavily on the development of particular psychomotor skills. The most common format of instruction and evaluation in tooth preparation at many Dental Faculties, emphasizes the product (tooth preparation) and associates performance with characteristics of this product. This integrated study examines which skills should be developed and how a course of instruction can best be structured to develop the necessary skills. The skills which are identified are those necessary for tooth preparation are selected from a psychomotor taxonomy. The purpose of evaluating these skills is identified. Behavioral objectives are set for student performance and the advisability of establishing standards of performance is examined. After reviewing studies related to learning strategy for dental psychomotor the most suitable tasks as well as articles on instructor effectiveness a model is proposed. A pilot project at the University of Toronto, based on this proposed model is described. The paper concludes wi th a discussion of the implications of this proposed model.

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Abstract The study was undertaken to identify what motivates registered nurses to participate in continuing education activities. The primary questions were whether basic nursing education, employment status, clinical area, and position, as well as readiness for selfdirected learning influenced Canadian nurses' motivational orientations when deciding to participate in continuing education activities. Other individual differences (e.g., age) were also examined. The sample included 142 registered nurses employed at an urban community hospital. Three instruments were used for data collection: the Education Participation Scale, the Self-Directed Learning Readiness Scale, and a nursing survey consisting of demographic questions. Basic nursing education and employment status did not effect motivational orientation or self-directed learning readiness. Clinical area and level of position significantly influenced nurses' decisions to participate in continuing education activities. Motivational orientation had a significant relationship with selfdirected learning readiness. Implications for practice as a result of this study involves program planning and delivery. The identification of the motivational orientations of participants may assist in the development and delivery of continuing education programs that are beneficial, relevant, and address the identified learning needs of participants. Implications for future research also exist in relation to studying different groups of nurses, for example, registered nursing assistants, and investigating related issues, for example, what are the deterrents to participation in continuing education?

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A simple, low-cost concentric capillary nebulizer (CCN) was developed and evaluated for ICP spectrometry. The CCN could be operated at sample uptake rates of 0.050-1.00 ml min'^ and under oscillating and non-oscillating conditions. Aerosol characteristics for the CCN were studied using a laser Fraunhofter diffraction analyzer. Solvent transport efficiencies and transport rates, detection limits, and short- and long-term stabilities were evaluated for the CCN with a modified cyclonic spray chamber at different sample uptake rates. The Mg II (280.2nm)/l\/lg 1(285.2nm) ratio was used for matrix effect studies. Results were compared to those with conventional nebulizers, a cross-flow nebulizer with a Scott-type spray chamber, a GemCone nebulizer with a cyclonic spray chamber, and a Meinhard TR-30-K3 concentric nebulizer with a cyclonic spray chamber. Transport efficiencies of up to 57% were obtained for the CCN. For the elements tested, short- and long-term precisions and detection limits obtained with the CCN at 0.050-0.500 ml min'^ are similar to, or better than, those obtained on the same instrument using the conventional nebulizers (at 1.0 ml min'^). The depressive and enhancement effects of easily ionizable element Na, sulfuric acid, and dodecylamine surfactant on analyte signals with the CCN are similar to, or better than, those obtained with the conventional nebulizers. However, capillary clog was observed when the sample solution with high dissolved solids was nebulized for more than 40 min. The effects of data acquisition and data processing on detection limits were studied using inductively coupled plasma-atomic emission spectrometry. The study examined the effects of different detection limit approaches, the effects of data integration modes, the effects of regression modes, the effects of the standard concentration range and the number of standards, the effects of sample uptake rate, and the effect of Integration time. All the experiments followed the same protocols. Three detection limit approaches were examined, lUPAC method, the residual standard deviation (RSD), and the signal-to-background ratio and relative standard deviation of the background (SBR-RSDB). The study demonstrated that the different approaches, the integration modes, the regression methods, and the sample uptake rates can have an effect on detection limits. The study also showed that the different approaches give different detection limits and some methods (for example, RSD) are susceptible to the quality of calibration curves. Multicomponents spectral fitting (MSF) gave the best results among these three integration modes, peak height, peak area, and MSF. Weighted least squares method showed the ability to obtain better quality calibration curves. Although an effect of the number of standards on detection limits was not observed, multiple standards are recommended because they provide more reliable calibration curves. An increase of sample uptake rate and integration time could improve detection limits. However, an improvement with increased integration time on detection limits was not observed because the auto integration mode was used.

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The present set of experiments was designed to investigate the organization and refmement of young children's face space. Past research has demonstrated that adults encode individual faces in reference to a distinct face prototype that represents the average of all faces ever encountered. The prototype is not a static abstracted norm but rather a malleable face average that is continuously updated by experience (Valentine, 1991); for example, following prolonged viewing of faces with compressed features (a technique referred to as adaptation), adults rate similarly distorted faces as more normal and more attractive (simple attractiveness aftereffects). Recent studies have shown that adults possess category-specific face prototypes (e.g., based on race, sex). After viewing faces from two categories (e.g., Caucasian/Chinese) that are distorted in opposite directions, adults' attractiveness ratings simultaneously shift in opposite directions (opposing aftereffects). The current series of studies used a child-friendly method to examine whether, like adults, 5- and 8-year-old children show evidence for category-contingent opposing aftereffects. Participants were shown a computerized storybook in which Caucasian and Chinese children's faces were distorted in opposite directions (expanded and compressed). Both before and after adaptation (i.e., reading the storybook), participants judged the normality/attractiveness of a small number of expanded, compressed, and undistorted Caucasian and Chinese faces. The method was first validated by testing adults (Experiment I ) and was then refined in order to test 8- (Experiment 2) and 5-yearold (Experiment 4a) children. Five-year-olds (our youngest age group) were also tested in a simple aftereffects paradigm (Experiment 3) and with male and female faces distorted in opposite directions (Experiment 4b). The current research is the first to demonstrate evidence for simple attractiveness aftereffects in children as young as 5, thereby indicating that similar to adults, 5-year-olds utilize norm-based coding. Furthermore, this research provides evidence for racecontingent opposing aftereffects in both 5- and 8-year-olds; however, the opposing aftereffects demonstrated by 5-year-olds were driven largely by simple aftereffects for Caucasian faces. The lack of simple aftereffects for Chinese faces in 5-year-olds may be reflective of young children's limited experience with other-race faces and suggests that children's face space undergoes a period of increasing differentiation over time with respect to race. Lastly, we found no evidence for sex -contingent opposing aftereffects in 5-year-olds, which suggests that young children do not rely on a fully adult-like face space even for highly salient face categories (i.e., male/female) with which they have comparable levels of experience.

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The purpose of this study was to develop a new English assessment system to evaluate Chinese students' English communicative capacities. Since there is more interaction with people from English-speaking countries, Chinese people attach more importance to English oral skills, and a lot of Western English teaching methods were introduced into China to improve students' English communicative capacities. However, traditional paper-written examinations, like the English test of higher education entry examination, cannot evaluate it effectively. This study explored the perceptions of two Chinese English-language teachers and two Chinese students about English assessment system. A qualitative research method using telephone interviews was conducted in this study. The findings showed that the most possible ways to assess Chinese students' English communicative capacities were paper-written examination and person-machine conversations, although measures should be taken to improve these two models. On the other hand, the model of person-person conversation was the ideal assessment tool but was hard to achieve at the current stage.

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This study examined the use of mindfulness meditation in educator growth and professional development. The purpose was to create recommendations for an effective mindfulness meditation practice for educators. To this end, as the researcher is an educator as well as an experienced mindfulness meditation practitioner, the research methodology was self-study through narrative inquiry. The exploration of mindfulness meditation on the researcher’s personal and professional development was viewed through the lenses of Maslow’s hierarchy of needs and Mezirow’s transformational learning theory. These theories provided an analytical framework that guided this research. Themes were drawn from the exploration and connected with academic literature. The results were a mindfulness meditation framework for educators that is based on the Socratic Method, and utilizes the conceptual frameworks of Maslow’s hierarchy of needs and Mezirow’s transformational learning theory.