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51.
For most of the last two centuries, Native Greenlandic teachers had been left out of the decision-making process regarding effective education for Greenlandic students. Rather, Danish education and church officials, living in Denmark, made important pedagogical and curricular decisions with little to no input from local teachers (Jakobsen, 1999 Jakobsen, J. 1999. The Greenlandic public school in the tension between Greenlandic and Danish pedagogics in this century, Copenhagen, , Denmark: Master's thesis. Royal Danish School.  [Google Scholar]). This article describes a collaborative effort between Center for Research on Education, Diversity, and Excellence (CREDE) professional developers and Greenlandic teachers in the design and implementation of a coaching model that includes Native Greenlandic ways of teaching and learning. Implications for other professional developers and researchers in education doing similar work are included.  相似文献   
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OBJECTIVE: This study reports the prevalence of child sexual abuse of African American and European American women and compares the circumstances of these incidents to data collected a decade ago. METHOD: Stratified probability sampling was used to recruit comparable samples of African American and European American women in Los Angeles County for a larger study of women's sexual decision making. Incidents of contact abuse were obtained from women 18 to 36 years old in 1994 and compared to women with those demographic characteristics from a comparable 1984 dataset. The prevalence of abuse, characteristics of the victim, assault, alleged perpetrator, disclosure, and long-term effects by ethnic group affiliation were assessed. RESULTS: Of the total sample, 34% reported at least one incident prior to age 18. Ethnic differences were found with respect to prevalence, location of abuse, and number of incidents of rape. While comparisons made with the 1984 dataset revealed no significant difference in prevalence rates over the 10 year period, changes in circumstances were noted. CONCLUSIONS: Although the prevalence of child sexual abuse in Los Angeles County remained fairly stable, several circumstances of abuse underwent change. These characteristics are discussed in relation to how sexual abuse among ethnically diverse samples in Los Angeles County has changed over a decade and how these differences can help better tailor prevention messages to different communities.  相似文献   
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The traditional percentage and correlational methods of estimating reliability of duration recording were compared to the reliability obtained with an event-by-event examination of observers' records in which the actual percentage of time that the observers were in agreement was calculated. While observing standardized videotapes, eight volunteer undergraduate students recorded “studying” using a specific definition and “not eating” using a nonspecific definition. The order of persentation and level of definition specificity were reversed for eight additional volunteer observers. Recordings were done on an event recorder. It was found that the traditional percentage reliability scores were significantly higher than actual (event-by-event) observer agreement for both behaviors, at both levels of definition specificity. Correlational reliability coefficients were significantly greater than event-by-event scores for specific definitions only. Implications of the findings include the possibility that duration recording, which does not involve a permanent product (e.g., when using a stopwatch), may be periodically checked for reliability with an event recorder, or that interval recording may be used.  相似文献   
55.
Students' employment of meaning through cognitive strategies in a retention task was explored in terms of attributional assignment and/or divergent thinking. Students were randomly assigned to either a list of nonsense syllables or nonrelated words. Attributional assignment was measured by Lefcourt's Multidimensional-Multiattributional Causality Scales (MMCS – IV); divergent thinking was measured by Guilford's tests of Fluency, Flexibility, and Originality. A questionnaire assessing students' beliefs regarding success and failure was also administered. No relationship was found among attributional assignment as measured by the MMCS-IV, divergent thinking, and retention. Strategy use was not related to retention. Students' attributional beliefs regarding failure were predictive of retention for the nonsense syllables. Discussion suggests the need to distinguish between tactic and strategy through analysis of metacognitive processes. Interpretation of the results may indicate that the divergent-thinking measures were not sensitive enough and/or the retention task did not require these divergent-thinking skills.  相似文献   
56.
The increasing rate of child abuse and neglect is a special concern for educators who are legally mandated reporters of suspected maltreatment, are often the first to identify and refer children who have been harmed, are in contact with parents and are aware of the family conditions contributing to child maltreatment, and who must often work closely with other professionals in their efforts to support child victims and prevent further abuse. Moreover, children's emotional or behavioral problems, learning disabilities, or other difficulties often reflect broader problems that are associated with abuse or neglect. Consequently, understanding the causes and consequences of child maltreatment, and contemporary child protection efforts, is essential to educators in their efforts to assist victimized children. This article surveys current research on child maltreatment with particular attention to the challenges of child protection, the multidimensionality of child maltreatment (distinguishing physical abuse, physical neglect, sexual abuse, and psychological maltreatment), and hopeful new avenues for prevention. The implications of this research for educational professionals are emphasized.  相似文献   
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Major curriculum and assessment reforms in Australia have generated research interest in issues related to standards, teacher judgement and moderation. This article is based on one related inquiry of a large‐scale Australian Research Council Linkage project conducted in Queensland. This qualitative study analysed interview data to identify teachers’ views on standards and moderation as a means to achieving consistency of teacher judgement. A complementary aspect of the research involved a blind review that was conducted to determine the degree of teacher consistency without the experience of moderation. Empirical evidence was gained that most teachers, of the total interviewed, articulated a positive attitude towards the use of standards in moderation and perceived that this process produces consistency in teachers’ judgements. Context was identified as an important influential factor in teachers’ judgements and it was concluded that teachers’ assessment beliefs, attitudes and practices impact on their perceptions of the value of moderation practice and the extent to which consistency can be achieved.  相似文献   
59.
OBJECTIVE: According to sociological and ecological models of abuse, typically nonabusive parents could behave abusively towards their children under certain circumstances. The purpose of this study was to examine factors that place parents at risk of abusing their children by predicting parents' use of discipline practices and attitudes that may bias parents towards abusive behaviors, which we refer to as abuse-proneness. METHOD: A telephone interview was administered by the Gallup Organization to a nationally representative sample of 1,000 parents. Using a set of theoretically relevant risk factors, multiple regression was used to predict variations in parental attitudes (i.e., attitudes towards physical discipline and attitudes that devalue children) and parental discipline practices (i.e., physical discipline, nonphysical discipline, and verbal abuse). RESULTS: The findings confirmed the importance of examining elements of parental attitudes, history, personality characteristics, as well as religion and ideology in predicting abuse proneness. Child age also was an important predictor in all analyses except predicting parental attitudes that devalue children. The findings suggest also, however, that it may be unduly simplified to regard parents as somewhere on a continuum of nonpunitive to punitive disciplinarians. Social isolation was not a significant predictor in any of the analyses. CONCLUSIONS: Although many important theoretical predictors of abuse proneness were confirmed, many questions arise regarding the diversity of discipline practices that parents use, and the relevance of child's age and social isolation in predicting abuse proneness. Implications for practitioners and future research are discussed.  相似文献   
60.
We present a simple microchip device consisting of an overlaid pattern of micromagnets and microwells capable of capturing magnetically labeled cells into well-defined compartments (with accuracies >95%). Its flexible design permits the programmable deposition of single cells for their direct enumeration and pairs of cells for the detailed analysis of cell-cell interactions. This cell arraying device requires no external power and can be operated solely with permanent magnets. Large scale image analysis of cells captured in this array can yield valuable information (e.g., regarding various immune parameters such as the CD4:CD8 ratio) in a miniaturized and portable platform.The emergent need for point-of-care devices has spurred development of simplified platforms to organize cells across well-defined templates.1 These devices employ passive microwells, immunospecific adhesive islands, and electric, optical, and acoustic traps to manipulate cells.2–6 In contrast, magnetic templating can control the spatial organization of cells through its ability to readily program ferromagnetic memory states.7 While it has been applied to control the deposition of magnetic beads,8–13 it has not been used to direct the deposition of heterogeneous cell pairs, which may help provide critical insight into the function of single cells.14,15 As such, we developed a simple magnetographic device capable of arraying single cells and pairs of cells with high fidelity. We show this magnetic templating tool can use immunospecific magnetic labels for both the isolation of cells from blood and their organization into spatially defined wells.We used standard photolithographic techniques to fabricate the microchips (see supplementary material16). Briefly, an array of 10 × 30 μm cobalt micromagnets were patterned by a photolithographic liftoff process and overlaid with a pattern of dumbbell-shaped microwells formed in SU-8 photoresist (Fig. 1(a)). The micromagnets were designed to produce a predominantly vertical field in the microwells by aligning the ends of the micromagnet at the center of each well of the dumbbell. These features were deposited across an area of ≈400 mm2 (>50 000 well pairs per microchip) (Fig. 1(b)). Depending on the programmed magnetization state with respect to the external field, magnetic beads or cells were attracted to one pole and repelled by the other pole of each micromagnet, leading to a biased deposition (Fig. 1(c)).12Open in a separate windowFIG. 1.Magnetographic array for single cell analysis. (a) SEM image of the dumbbell-shaped well pairs for capturing magnetically labelled cells. (b) Photograph of the finished device. (c) An array of well pairs displaying a pitch of 60 × 120 μm before (top) and 10 min after the deposition of magnetic beads (bottom).To demonstrate the capability of the array to capture cells into a format amenable for rapid image processing, we organized CD3+ lymphocytes using only hand-held permanent magnets. We isolated CD3+ lymphocytes from blood via positive selection using anti-CD3 magnetic nanoparticles (EasySep™, STEMCELL Technologies) with purities confirmed by flow cytometry (97.8%; see supplementary material16). We then stained 1 × 106 CD3+ cells with anti-CD8 Alexa-488 and anti-CD4 Alexa-647 (5 μl of each antibody in 100 μl for 20 min; BD Bioscience) to determine the CD4:CD8 ratio, a prognostic ratio for assessing the immune system.17,18Variably spaced neodymium magnets (0.5 in. × 0.5 in. × 1 in.; K&J Magnetics, Inc.) were fixed on either side of the microchip to generate a tunable magnetic field (0–400 G; Fig. 2(a)). Using this setup, fluorescently labeled cells were deposited, and the populations of CD4+ and CD8+ cells were indiscriminately arrayed, imaged, and enumerated using ImageJ. The resulting CD4:CD8 ratio of 1.84 ± 0.18 (Fig. 2(b)) was confirmed by flow cytometry with a high correlation (5.4% difference; Fig. 2(c)), indicating the magnetographic microarray can pattern cells for the rapid and accurate assessment of critical phenotypical parameters without complex equipment (e.g., function generators or flow cytometers).Open in a separate windowFIG. 2.CD8 analysis of CD3+ lymphocytes. (a) Photograph of the magnetographic device activated by permanent magnets (covered with green tape). The CD4:CD8 ratio determined by the (b) magnetographic microarray and (c) and (d) flow cytometry was 1.84 and 1.74, respectively.More complex operations, such as the programmed deposition of cell pairs, can be achieved by leveraging the switchable, bistable magnetization of the micromagnets for the detailed studies of cell-cell interactions (Figs. 3(a)–3(d)).12 For these studies, a 200 G horizontal field generated from an electromagnetic coil was used to magnetize the micromagnets.19 We then captured different concentrations of magnetic beads as surrogates for cells (8.4 μm polystyrene, Spherotech, Inc.) and found that higher bead concentrations did not affect the capture accuracy (>95%; see supplementary material16).Open in a separate windowFIG. 3.Programmed pairing of magnetic beads and CD3+ lymphocytes. (a) Schematic of the magnetographic cell pair isolations. (b) Polarized micromagnets isolate cells of one type to one side in a vertical magnetic field and then cells of a second type to the other side when the field is reversed. (c) Fluorescent image of magnetically trapped green stained (top) and red stained (bottom) cell pairs. (d) SEM image of magnetically labeled cells in the microwells. (e) Capture accuracy of magnetic bead pairs. (Each color (and shape) represents the field strength of the reversed field.) (f) Change in the capture accuracy (loss) of initially captured beads after reversing the magnetic field. The capture accuracy of (g) magnetically labeled cell pairs and (h) the second magnetically labeled cell (for (e)–(h): n = 5; time starts from the deposition of the second set of cells or beads).The opposite side of each micromagnet was then populated with the second (yellow fluorescent) bead by reversing the direction of the applied magnetic field. We tested several field strengths (i.e., 10, 25, 40, or 55 G) to optimize the conditions for isolating the desired bead in the opposite well without ejecting the first bead. If the field strength was too large, the previously deposited beads could be ejected from their wells due to the repulsive magnetic force overcoming gravity.12 As shown in Figure 3(e), increasing the field strength from 10 to 25 G significantly increased the capture accuracy at 60 min from the deposition of the second bead (p < 0.01), but increases from 25 to 55 G did not affect the capture accuracy (p > 0.10). As shown in Figure 3(f), higher field strengths (i.e., 40 and 55 G) resulted in lower capture accuracies compared to lower field strengths (i.e., 10 and 25 G) (p < 0.01), which was primarily due to ejection of the initially captured beads when the micromagnets reversed their polarity.We then arranged pairs of membrane dyed (calcein AM, Invitrogen; PKH26, Sigma) magnetically labeled CD3+ lymphocytes. First, red stained cells (150 μl of 2 × 104 cells/ml) were deposited on the microchip in the presence of 250 G vertical magnetic field. After 20 min, the field was reversed (i.e., to 40, 55, and 70 G) and green stained cells (150 μl of 2 × 104 cells/ml) were deposited on the microchip with images taken in 10 min intervals. Fluorescence images were overlaid (Fig. 3(c)) and the capture accuracy of cell pairs was determined (ImageJ).As seen in Figure 3(g), the capture accuracy of pairs of CD3+ lymphocytes was lower than that of magnetic beads (Fig. 3(e)). However, as shown in Figure 3(h), the second set of cells (green fluorescent) exhibited an average capture accuracy of 91.8% ± 1.9%. This indicates that the lower capture accuracy of cell pairs was either due to the ejection of initially captured (red fluorescent) cells or the migration of initially captured cells through the connecting channel, resulting from their relatively high deformability compared to magnetic beads.In summary, we developed a simple device capable of organizing magnetic particles, cells, and pairs of cells into well-defined compartments. A major advantage of this system is the use of specific magnetic labels to both isolate cells and program their deposition. While the design of this device does not enable dynamic control of the spacing between captured cell pairs as does some dielectrophoresis-based devices,20 it can easily capture cells with high fidelity using only permanent magnets and has clinical relevance in the assessment of immune parameters. These demonstrations potentiate a relatively simple and robust device where highly organized spatial arrangement of cells facilitates rapid and accurate analyses towards a functional and low-cost point-of-care device.  相似文献   
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