Dielectrophoretic manipulation of ribosomal RNA

The manipulation of ribosomal RNA (rRNA) extracted from E. coli cells by dielectrophoresis (DEP) has been demonstrated over the range of 3 kHz-50 MHz using interdigitated microelectrodes. Quantitative measurement using total internal reflection fluorescence microscopy of the time dependent collection indicated a positive DEP response characterized by a plateau between 3 kHz and 1 MHz followed by a decrease in response at higher frequencies. Negative DEP was observed above 9 MHz. The positive DEP response below 1 MHz is described by the Clausius-Mossotti model and corresponds to an induced dipole moment of 3300 D with a polarizability of 7.8×10(-32) F m(2). The negative DEP response above 9 MHz indicates that the rRNA molecules exhibit a net moment of -250 D, to give an effective permittivity value of 78.5 ε(0), close to that of the aqueous suspending medium, and a relatively small surface conductance value of ～0.1 nS. This suggests that our rRNA samples have a fairly open structure accessible to the surrounding water molecules, with counterions strongly bound to the charged phosphate groups in the rRNA backbone. These results are the first demonstration of DEP for fast capture and release of rRNA units, opening new opportunities for rRNA-based biosensing devices.     

Multiple mediation analysis of the relationship between rapid naming and reading

It is well established that rapid automatised naming (RAN) correlates with reading ability. Despite several attempts, no single component process (mediator) has been identified that fully accounts for the correlation. The present paper estimated the explanatory value of several mediators for the RAN–reading correlation. One hundred and sixty‐nine preschool students were given measures of RAN and additional measures of phonological awareness, lexical search speed, letter knowledge and paired associate learning. Their reading skills were tested a year later along with speed of processing. The influence of the mediators on the RAN–reading correlation was estimated as indirect effects in mediation analyses. Phonological awareness and letter knowledge significantly mediated the RAN–reading relationship, each accounting for a moderate part of the correlation between RAN and reading fluency. Thus, the RAN–reading correlation was partly, but not fully, accounted for by precursors of reading that are currently known.     

Recent educational research on developing countries by German researchers: A survey of the literature

How have recent trends in German educational research applied to developing countries? In order to outline the immediate state of this research in the FRG (1980–1983), the contribution first gives a brief review of its process from the beginning. The first part examines educational research until 1980, and then differentiates three main types of research on educational problems in Third World countries (on the implementation of projects; on the evaluation of education programmes and measures of educational aid; on education systems and the correlation between education and development). Through a survey of the literature published since 1980, the article aims to give an idea of the contemporary topics of this research and furthermore tries to show how German educationists try to come to terms with the failures of educational aid projects, also how they try to construct new and adequate theoretical models.     

Licensing as a commercialisation strategy for new technology-based firms

We investigate licensing as a commercialisation strategy for new technology-based firms (NTBFs) in the biopharmaceutical industry using a combination of survey and database research methods. We found that most firms in our sample were not fully integrated regardless of their company age which is consistent with the picture of NTBFs as agents of technology transfer. Comparing fully and not-fully integrated firms we find differences in the use of licensing strategies. According to Ford and Ryan [Harvard Business Review 59 (1981) 117] fully integrated companies apply licensing for strategic reasons and for financially unattractive projects. Our results provide partial support for this theory.     

Do Belonging and Social Exclusion at School Affect Structural Brain Development During Adolescence?

Students’ sense of belonging presents an essential resource for academic and health outcomes, whereas social exclusion at school negatively impacts students’ well-being and academic performance. Aiming to understand how feelings of school-related belonging and exclusion shape the structural brain development, this study applied longitudinal questionnaire-based data and MRI data from 71 adolescent students (37 females, M_age at t1 = 15.0; t2 = 16.1 years). All were white participants from Germany. Voxel-based morphometry revealed only an association of social exclusion (and not of belonging) and gray matter volume in the left anterior insula: From t1 to t2, there was less gray matter decrease, the more social exclusion students perceived. School-related social exclusion and disturbed neurodevelopment are thus significantly associated.     

Teachers' predictions and pupils' destinies: A West African survey

This article presents a case study of the primary schooling and post-primary careers of a group of West African pupils. Their school performance and later careers were studied in relation to a number of variables, some relating to the school itself, others to background factors. Among the most important of the former were the predictions made by teachers about the pupils' ability to succeed. While teachers' predictions tended to be fairly accurate, they also functioned to some extent as self-fulfilling prophecies. The study shows that socio-economic and cultural variables are as important as school variables in explaining variations in former pupils' geographical location and socio-economic position eight to nine years later. The study has implications in relation to the improvement of the quality of primary education, since out-of-school variables cannot be manipulated through educational policies alone.

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Zusammenfassung In dem vorliegenden Artikel werden Ergebnisse einer westafrikanischen Studie dargestellt, die sich mit dem Schulbesuch und mit der Laufbahn nach abgeschlossenem Schulbesuch beschäftigt. Die Ausbildung der Schüler in zwei senegalischen Dörfern und ihre Laufbahn nach der Ausbildung werden im Verhältnis zu gewissen Schulvariablen und Hintergrundsvariablen studiert. Unter den erstgenannten waren die Voraussagen der Lehrer über die Möglichkeit der Schüler, von einer Klasse in die nächste versetzt zu werden, wichtig. Die Annahmen der Lehrer waren ziemlich sicher, aber sie funktionierten auch in hohem Grade als selbsterfüllende Prognosen. Die Studie zeigt, daß sozioökonomische und kulturelle Variablen genauso aussagekräftig sind wie Schulvariablen, wenn man die Unterschiede in dem geographischen Wohnort und in der sozioökonomischen Position der früheren Schüler acht bis neun Jahre später erklären will. Das hat Implikationen für eine Menge Richtlinien und Vorschläge, die in den letzten Jahren im Hinblick auf die Verbessergung der Qualität der Schule vorgelegt wurden, weil sich die Variablen außerhalb der Schule durch rein bildungspolitische Maßnahmen nicht manipulieren lassen.

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Resumen Este artículo presenta los resultados de un estudio que se ocupa de la enseñanza primarla y de las carreras post-primarias en un grupo de alumnos de Africa Occidental. La formación que recibieron los alumnos en dos pueblos senegaleses y las carreras que hicieron después de la escuela se estudian en cuanto a determinadas variables; relacionadas con la escuela misma y con el medio. Una de las más importantes de la primera catgoría eran las predicciones que los maestros hacían sobre las posibilidades que tendrían los alumnos de pasar al grado superior. las suposiciones de los maestros eran bastante acertadas, pero también funcionaban, en bueno grado, como pronósticos que se cumplirían automáticamente. El estudio demuestra que las variables socioeconómicas y culturales son tan importantes como las variables escolares, si se quieren explicar, ocho u nueve años desputés, las diferencias en localizatión geográfica y posición socioeconómica de los antiguou alumnos. Esto tiene implicaciones en una cantidad de directivas y sugerencias que se presentaron en los ültimos años para mejorar la calidad de la enseñanza primaria, ya que las variables del entorno extra-escolar no pueden manipularse a través de meras medidas de política educacional.

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Résumé Cet article présente une étude de cas en Afrique Occidentale se rapportant à l'enseignement primaire et aux carrières post-primaires, le succès scolaire des élèves ainsi que leurs carrières sont examinés par rapport à des variables scolaires et des variables concernant le milieu de l'élève constituent les variables importantes. Ces prédictions sont pluôt exactes, mais dans une certaine mesure elles relèvent de la prédiction qui s'accomplit automatiquement. L'étude démontre que les variables socio-économiques et culturelles sont aussi importantes que les variables scolaires; elles expliques les variations les variations dans la localisation géographique ainsi que le statut socio-économique de l'élève entre huit ans et neuf ans plus tard. Ceci a des implications pour un grand nombre de suggestions soumises récemment pour améliorer la qualité de l'enseignement primaire primaire étant donné qu'il est impossible de modifier les variables extra-scolaires uniquement à travers la politique de l'éducation.

     

Priced Out?

While the literature on postsecondary student success identifies important academic and social factors associated with student outcomes, one question that persists concerns the influence of financial aid. We use the National Student Clearinghouse’s StudentTracker service to develop a more complete model of student success that accommodates opportunities for students to choose to either graduate from the university of first-entry, graduate from a transfer university, or depart from college without a degree. The multinomial regression model reveals differential effects of financial aid. Results suggest that loan aid appears to encourage students to search out alternative institutions or drop out of college entirely, and merit aid appears to increase the likelihood of students persisting and graduating from the university of first-entry.     

找到心仪工作,只需六招

Whether your preferred destination is the executive suite or simply the nearest exit from your current position, don't let your job take you aimlessly down any path. In fact when it comes to career planning, don't think in terms of "jobs" at all, says corporate transitions expert William Bridges, Ph.D. Instead he suggests building your career plan on "doing the work you're best at for the employers who need it."