An exercises editor for an e-learning environment

One of the most important tenets of e-learning is that it bridges work and learning. A great e-learning experience brings learning into the work environment. This is a key point, the capacity to construct a work environment when the student can develop proper tasks to complete the learning process. This paper describes a work environment based on the development of two tools, an exercises editor and an exercises viewer. Both tools are able to manage color images where, because of the implementation of basic steganographic techniques, it is possible to add information, exercises, questions, and so on. The exercises editor allows to decide which information must be visible or remain hidden to the user, when the image is loaded in the exercises viewer. Therefore, it is possible to hide the solutions of the proposed tasks; this is very useful to complete a self-evaluation learning process. These tools constitute a learning architecture with the final objective that learners can apply and practice new concepts or skills.

An optimized pseudorandom generator using packed matrices

Most cryptographic services and information security protocols require a dependable source of random data; pseudorandom generators are convenient and efficient for this application working as one of the basic foundation blocks on which to build the required security infrastructure. We propose a modification of a previously published matricial pseudorandom generator that significantly improves performance and security by using word packed matrices and modifying key scheduling and bit extraction schemes. The resulting generator is then successfully compared to world class standards.

Atención quirúrgica en hombres y mujeres ¿Diferente o desigual?

Explorar la posible existencia de sesgos de género en procedimientos quirúrgicos (PQ) frecuentes y en sus estancias medias (EM) postquirúrgicas es objetivo del presente trabajo, mediante su comparación entre sexos en el Servicio de Cirugía General y Digestiva del Hospital General de Alicante (2000-2004). Se intervienen más hombres que mujeres en 4 de los 7 PQ estudiados, apuntando posibles sesgos de género en el patrón quirúrgico, como por apendicectomías agudas (1,36 Hombres/1 Mujer) y complicadas (1,79/1). La estancia postapendicectomías, a igual edad y comorbilidad, es de 2 días más en hombres (9,49) que en mujeres (7,5). No detectar diferencias por sexo en colecistectomías por colecistitis (más frecuentes en mujeres), puede indicar colelitiasis evolucionadas por no sospecha diagnóstica en hombres.