'Simpel is het moeilijkst'

HeT-A_pi1, a piRNA Target Sequence in the Drosophila Telomeric Retrotransposon HeT-A, Is Extremely Conserved across Copies and Species

The maintenance of the telomeres in Drosophila species depends on the transposition of the non-LTR retrotransposons HeT-A, TAHRE and TART. HeT-A and TART elements have been found in all studied species of Drosophila suggesting that their function has been maintained for more than 60 million years. Of the three elements, HeT-A is by far the main component of D. melanogaster telomeres and, unexpe...

SIMPEL: circuit model for photonic spike processing laser neurons.

We propose an equivalent circuit model for photonic spike processing laser neurons with an embedded saturable absorber—a simulation model for photonic excitable lasers (SIMPEL). We show that by mapping the laser neuron rate equations into a circuit model, SPICE analysis can be used as an efficient and accurate engine for numerical calculations, capable of generalization to a variety of differen...

39-47_0408PP_aan het Rot_CME.indd

Conventional pharmacologic treatments for major depressive disorder (MDD) generally take several weeks to several months to have a clinically meaningful effect. This time lag to response constitutes a major burden for patients and contributes to increased morbidity and mortality. Two published studies in patients with MDD have now provided evidence for rapid and robust antidepressant efficacy o...

Computational Problems without Computation

Problemen uit de discrete wiskunde lijken op het eerste gezicht vaak erg simpel. Ze kunnen meestal gemakkelijk en zonder gebruik te maken van wiskundige begrippen worden geformuleerd. Toch komt het vaak voor dat zo’n ogenschijnlijk eenvoudig probleem nog open is of dat er, zoals bij het handelsreizigersprobleem, wel een oplossing gegeven kan worden, maar alleen een die onbruikbaar is omdat de r...

Op En in Het Web