Student Perspectives in Advanced Placement for First-Year and Traditionally Underrepresented Students: Successes, Challenges, and Shifts in Their Academic Identity

This study examined the perceptions of first-year Advanced Placement (AP) students; specifically traditionally underrepresented AP students from a high school that attempted to align its AP enrollment to the demographics of its school. This research contributed to the body of knowledge around first-year and traditionally underrepresented students participating in AP courses by identifying their perceived supports and challenges in their AP courses through a pre- and post-survey (n = 81) as well as selected student interviews (n = 5). The importance of this study is the student perspectives about the supports, the challenges, and their perceived changes that occurred in their academic identity while enrolled in the AP class. The first phase of this research analyzed the marks students earned in their AP classes, scores from their AP exams, and survey data to identify student perceptions of supports and challenges in their AP classes. At the end of the first phase, changes in their perceived academic identity were analyzed from responses on pre- and post-surveys. The second phase of the research design included interviews of purposefully selected students to gain a deeper understanding of the findings from the first phase of the study. The factor that most helped first-year students succeed was that their AP teacher believed they could be successful in the class. The quantitative survey data and student interviews revealed that students were challenged by the difficulty of content in AP classes, the amount of work, and managing their time. First-year AP students exhibited statistically significant decreases (p \u3c .05) from the pre- to post-AP survey in their perceptions of their academic self and academic strategies. The results and implications from this study are discussed and may provide insight for suburban high schools that are experiencing a shift in student demographics to better meet the academic needs of all students in AP

Playground Improvement Plan

Physical activity is important to the growth and development of children of all ages. The purpose of this paper is to use what we know about physical activity and the connection between social development, cognitive development and overall health to physical activity to improve the current opportunities for physical activity in school age children. Fundamental movement skills (FMS) mastery level of students will be used to implement this improvement plan as well as incorporating more physical activity opportunities in the school day to promote more movement and less sedentary time in the school day on a regular basis and to improve the current playground. The use of the SOPLAY method will be used as an observation tool

Verbraucherakzeptanz umweltfreundlicher Lebensmittelverpackung am Beispiel von Öko-Salami

Die vorliegende Studie hat untersucht, welchen Einfluss umweltfreundliche Verpackung auf die Produktwahrnehmung, Kaufentscheidung und Zahlungsbereitschaft von Verbrauchern hat. Es wurden Verbraucher computergestützt vor Supermärkten befragt und die Daten multivariat ausgewertet. Anhand der Ergebnisse wird aufgezeigt, was eine umweltfreundliche Verpackung erfüllen muss, um von Verbrauchern positiv wahrgenommen zu werden. Darüber hinaus wird der Einfluss der Produktwahrnehmung auf die Kaufentscheidung und Zahlungsbereitschaft von Verbrauchern dargestellt

A new fabrication method for precision antenna reflectors for space flight and ground test

Communications satellites are using increasingly higher frequencies that require increasingly precise antenna reflectors for use in space. Traditional industry fabrication methods for space antenna reflectors employ successive modeling techniques using high- and low-temperature molds for reflector face sheets and then a final fit-up of the completed honeycomb sandwich panel antenna reflector to a master pattern. However, as new missions are planned at much higher frequencies, greater accuracies will be necessary than are achievable using these present methods. A new approach for the fabrication of ground-test solid-surface antenna reflectors is to build a rigid support structure with an easy-to-machine surface. This surface is subsequently machined to the desired reflector contour and coated with a radio-frequency-reflective surface. This method was used to fabricate a 2.7-m-diameter ground-test antenna reflector to an accuracy of better than 0.013 mm (0.0005 in.) rms. A similar reflector for use on spacecraft would be constructed in a similar manner but with space-qualified materials. The design, analysis, and fabrication of the 2.7-m-diameter precision antenna reflector for antenna ground tests and the extension of this technology to precision, space-based antenna reflectors are described

Udviklingen i instruktør- og lederuddannelsen inden for DDSG&I

Artiklen beskriver i et historisk perpsektiv fremkomsten af og udviklingen i foreningers ledelsesuddannelser i DDSG&I regi

Thymic nurse cells. Lymphoepithelial cell complexes in murine thymuses: morphological and serological characterization

We describe a new cellular component of normal mouse thymuses, which is isolated by fractionated trypsin dissociation of minced thymus tissue followed by repeated unit gravity sedimentation. These cells are of unusually large size, with diameters of 30 μm and more. They represent cellular complexes of single large cells filled with high numbers of lymphoid cells. The majority of the engulfed lymphoid cells is not only fully intact, as judged by morphological criteria, but, moreover, includes a high proportion of mitotic figures. Electron microscopic investigations reveal the epithelial character of the large thymic nurse cells (TNC). The peripherally situated cytoplasmic tonofilament streams, and characteristic vacuoles filled with coarse, unidentified material, closely resemble cytoplasmic organelles found in the cortical reticuloepithelial cells described in situ. The internalized lymphocytes are located within caveolae lined by plasma membranes. These TNC caveolae are completely sequestered, and have lost any communication with the extracellular space, as demonstrated by the inability of an electrondense marker, cationized ferritin, to diffuse into the perilymphocytic clefts. The structural interactions between the membranes of the engulfed thymocytes with the surrounding TNC caveolar membranes were investigated both in ultrathin sections and in freeze-etch preparates. Two distinct contact types between both membranes were discerned: (a) complete, close contact along the entire lymphocyte circumference, and (b) more frequently, contact restricted to discrete, localized areas. Judging from their size and distribution, the localized contacts could correspond particle aggregates of freeze-etch preparates, which morphologically resemble certain stages of gap junction. Furthermore, we regularly found square arrays of particles of uniform size, which so far have been thought to be typical for cell membranes actively engaged in ion exchange. Tight junction-like particle arrays, which were present on TNC outer membranes, and probably represented disrupted contacts between adjacent TNC in the intact tissue, could not be found on caveolar or lymphocyte membranes. Finally, one of the most conspicuous specializations of the TNC caveolar membrane were membrane invaginations, which were arranged mainly in groups, and which probably reflect endo- or exocytotoxic events. We investigated the surface antigen phenotype of TNC by indirect immunofluorescence, with monoclonal antibodies against determinants of H-2- complex subregions as well as against lymphocyte differentiation markers. Semiquantification was reached with flow cytofluorimetry, followed by morphological control by fluorescence microscopy. The surface antigen formula of TNC is: Ig(-), Thy-l(-), H-2K(++), I-A (++), I-E/C(+), H-D(++), Ly-1(-), Ly-2(-), Qat-4(-), Qat-5(-), and peanut agglutinin (PNA)(-). Thymic macrophages, which were identified by double fluorescence, with rhodamine- coupled zymosan as a phagocytosis marker, were serologically identical with TNC. Free thymocytes, in contrast, had the following antigen formula: Ig(-), Thy-1(++), H-2K(+/-), I-A(-), I-E/C(-), H-2D(+/-), Ly-1(+/-), Ly-2(+), Qat- 4(-), Qat-5(-), and PNA(+). The unprecedented finding of high numbers of dividing thymocytes sojourning within thymic epithelial cells, and the particular specializations of the TNC caveolar membranes surrounding these engulfed thymocytes is the basis of a hypothesis that postulates that an intraepithelial differentiation cycle is one essential step in, intrathymic T lymphocyte generation

Udviklingen i instruktør- og lederuddannelsen inden for DDSG&I

Artiklen beskriver i et historisk perpsektiv fremkomsten af og udviklingen i foreningers ledelsesuddannelser i DDSG&I regi