Perspectives on peer-review: eight years of Aropä

Drawing on eight years of observation and correspondence from the Aropä project, we report on the issues important to academics who conduct on-line student peer-review activities, and the features they request to support their own instructional designs. The Aropä project is unusually broad, having so far supported over 100 instructors at 20 institutions across nine countries, almost one thousand activities, and more than 36,000 individual students. As the designers, developers, maintainers and advisors of an evolving and widely used tool, we use our unique position to report on the perspectives and priorities of instructors and students in this important and developing field

Peer-review in practice: eight years of Aropä

Articles discussing and analysing student peer-review activities proliferate the educational literature, typically describing one or more class exercises where students provide feedback on each other’s work. These papers usually focus on a peer-review activity designed as a scholarly study, and make conclusions about its success or otherwise. There is not one standard model for ‘peer-review’, and information on the many different assessment designs used is distributed over an increasing number of publications and websites. This paper provides a meta-review of peer-review activities as they are implemented in practice, using configuration data from over a thousand assignments conducted using an online peer-review system during an eight-year period. We present data on the wide variety of assignment designs and the parameters that comprise them, their rubrics, and comparisons between subject areas. Information on the norms and range of all decisions to be made will encourage instructors (both new to and experienced in conducting peer-review activities) to reflect on and justify the choices they make

Existence of the dielectric constant in dipolar fluid mixtures

The existence of the dielectric constant epsilon is investigated for fluid mixtures of rigid polar molecules. The investigation is performed using the functional-derivative formalism for mixtures, and is closely analogous to that previously carried out for pure dipolar fluids (J. Chem. Phys. 68, 5199 (1978)). Sufficient conditions for the existence of epsilon are obtained in terms of the direct correlation function matrix c/sub alphabeta/(12). It is found that epsilon exists if c/sub alphabeta/(12) depends only on relative positions and orientations, and becomes asymptotic to -theta/sub alphabeta/(12)/kT at long range, where theta/sub alphabeta/(12) is the dipole--dipole potential between a molecule of species ..cap alpha.. and one of species ..beta... An expression for epsilon in terms of the short-range total correlation function matrix emerges automatically from the development. This expression is equivalent to an earlier result obtained by a different method. Expressions for epsilon in terms of c/sub alphabeta/(12) are derived for axially symmetric molecules and for molecules of arbitrary symmetry. In the former case, the expression involves the inverse of an N/sub c/ x N/sub c/ matrix, where N/sub c/ is the number of components in the mixture. This expression facilitates the evaluation of epsilon in the mean spherical approximation. For molecules of arbitrary symmetry, the expression for epsilon in terms of c/sub alphabeta/(12) involves the inverse of an N/sub c/ x N/sub c/ supermatrix, each element of which is a 3 x 3 matrix

Assessment of Magnaporthe grisea mating type by spore PCR

Isolation of DNA from filamentous fungi for PCR analysis is usually time consuming and involves use of toxic chemicals such as phenol/chloroform. In Saccharomyces cerevisiae, PCR assay can be performed with yeast colonies (Huxley et al. TIG 1990 6:236). Here we describe a PCR protocol which uses M. grisea conidia directly for PCR analysis without extraction of DNA

A medium for rapid cleaning of Aspergillus cleistothecia

Aspergillus cleistothecia are usually cleaned of adherent Hülle cells by rolling them on an agar surface, which is a tedious process. We have found that incorporating 0.5 - 1.0 % diatomaceious earth (also caled Celite) into 4% agar, as a mild abrasive, helps to speed cleaning about 5-fold (average 10 min reduced to 2 min)

Preeclampsia como factor de riesgo para criptorquidia congénita en neonatos a termino

Determinar si la preeclampsia constituye como un factor de riesgo para la criptorquidia congénita en neonatos a término. Material y métodos: Se realizó un estudio analítico de casos y controles que incluyo 1194 neonatos a término, según criterios de selección que se distribuyeron la presencia o no de criptorquidia, se calculó el chi cuadrado y el estadígrafo odds ratio. Resultados: La frecuencia de peso adecuado para edad gestacional y embarazo múltiple fueron significativamente menores en el grupo de neonatos con criptorquidia congénita (p<0.05), la frecuencia de preeclampsia en neonatos a termino con criptorquidia es de 27%, la frecuencia de preeclampsia en neonatos a termino con criptorquidia es de 18%, la preeclampsia como factor de riesgo para criptorquidia congénita en neonatos a término con un odds ratio de 1.71 el cual fue significativo (p<0.05), en el análisis multivariado se corrobora la significancia de la asociación para preeclampsia como factor de riesgo y peso adecuado para edad y embarazo múltiple como factores protectores para criptorquidia. Conclusión: la preeclampsia constituye un factor de riesgo para la criptorquidia congénita en neonatos a término.To demonstrate that preeclampsia is a risk factor for congenital cryptorchidism in term neonates. Material and methods: An analytical study was carried out, t of cases and controls in which 1194 full-term neonates were included, according to selection criteria which were divided according to the presence or not of cryptorchidism, the chi square was calculated. and the odds ratio statistician. Results: The frequency of adequate weight for gestational age and multiple pregnancy were significantly lower in the group of neonates with congenital cryptorchidism (p<0.05), the frequency of preeclampsia in term neonates with cryptorchidism is 27%, the frequency of preeclampsia in term neonates with cryptorchidism is 18%, preeclampsia as a risk factor for congenital cryptorchidism in term neonates with an odds ratio of 1.71 which was significant (p<0.05), the multivariate analysis corroborates the significance of the association for preeclampsia as a risk factor and adequate weight for age and multiple pregnancy as protective factors for cryptorchidism. Conclusion: preeclampsia is a risk factor for congenital cryptorchidism in term neonates.Tesi

Applications of Power Spectral Analysis Methods to Maneuver Loads Obtained on Jet Fighter Airplanes During Service Operations

Power spectral densities of normal load factor have been obtained for two service operational training flights of a Republic F-84G airplane and three service operational training flights of a North American F-86A airplane in order to indicate the load-factor frequency content and possible uses of power spectral methods in analyzing maneuver load data. It was determined that the maneuvering load-factor time histories appeared to be described by a truncated normal distribution. The power spectral densities obtained were relatively level at frequencies below 0.03 cycle per second and varied inversely with approximately the cube of the frequency at the higher frequencies. In general, the frequency content was very low above 0.2 cycle per second. The load-factor peak distributions were estimated fairly well from the spectrum analysis. In addition, peak load data obtained during service operations of fighter-type airplanes with flight time totaling about 24,000 hours were examined and appeared to agree reasonably well with the type of equations obtained from spectrum peak-load distributions