Training basic laparoscopic skills using a custom-made video game

Video games are accepted and used for a wide variety of applications. In the medical world, research on the positive effects of playing games on basic laparoscopic skills is rapidly increasing. Although these benefits have been proven several times, no institution actually uses video games for surgical training. This Short Communication describes some of the theoretical backgrounds, development and underlying educational foundations of a specifically designed video game and custom-made hardware that takes advantage of the positive effects of games on basic laparoscopic skills

Temperature effects on DNA damage during hibernation

During multiday torpor, deep-hibernating mammals maintain a hypometabolic state where heart rate and ventilation are reduced to 2%–4% of euthermic rates. It is hypothesized that this ischemia-like condition may cause DNA damage through reactive oxygen species production. The reason for intermittent rewarming (arousal) during hibernation might be to repair the accumulated DNA dam-age. Because increasing ambient temperatures (Ta’s) shortens torpor bout duration, we hypothesize that hibernating at higher Ta’swill result in a faster accumulation of genomic DNA damage. To test this, we kept 39 male and female garden dormice at a Ta of either 57C or 107C and obtained tissue at 1, 4, and 8 d in torpor to assess DNA damage and recruitment of DNA repair markers in splenocytes. DNA damage in splenocytes measured by comet assay was significantly higher in almost all torpor groups than in sum-mer euthermic groups. Damage accumulates in the first days of torpor at Ta = 57C (between days 1 and 4) but not at Ta = 107C. At the higher Ta, DNA damage is high at 24 h in torpor, indicating either a faster buildup of DNA damage at higher Ta’soranin-complete repair during arousals in dormice. At 57C, recruitment of the DNA repair protein 53BP1 paralleled the increase in DNA damage over time during torpor. In contrast, after 1 d in torpor at 107C, DNA damage levels were high, but 53BP1 was not re-cruited to the nuclear DNA yet. The data suggest a potential mis-match in the DNA damage/repair dynamics during torpor at higher Ta’s.</p

CubeSpec, A Mission Overview

CubeSpec is an in-orbit demonstration CubeSat mission in the ESA technology programme, developed and funded in Belgium. The goal of the mission is to demonstrate high-spectral-resolution astronomical spectroscopy from a 6-unit CubeSat. The prime science demonstration case for the in-orbit demonstration mission is to unravel the interior of massive stars using asteroseismology by high-cadance monitoring of the variations in spectral line profiles during a few months. The technological challenges are numerous. The 10x20cm aperture telescope and echelle spectrometer have been designed to fit in a 10x10x20cm volume. Under low-Earth orbit thermal variations, maintaining the fast telescope focus and spectrometer alignment is achieved via an athermal design. Straylight rejection and thermal shielding from the Sun and Earth infrared flux is achieved via deploying Earth and Sunshades. The narrow spectrometer slit requires arcsecond-level pointing stability using a performant 3-axis wheel stabilised attitude control system with star tracker augmented with a fine beam steering mechanism controlled in closed loop with a guiding sensor. The high cadence, long-term monitoring requirement of the mission poses specific requirements on the orbit and operational scenarios to enable the required sky visibility. CubeSpec is starting the implementation phase, with a planned launch early 2024

Looping caterpillars

There are two main paradigms for querying semi structured data: regular path queries and XPath. The aim of this paper is to provide a synthesis between these two. This synthesis is given by a small addition to tree walk automata and the corresponding caterpillar expressions. These are evaluated on unranked finite sibling-ordered trees. At the expression level we add an operator whose meaning is intersection with the identity relation. This language can express every first-order definable relation and its expressive power is characterized by pebble tree walk automata that cannot inspect pebbles. We also define an expansion of the caterpillar expressions whose expressive power is characterized by ordinary pebble tree walk automata. Combining results from Bloem–Engelfriet and Gottlob–Koch, we also define an XPath like query language which is complete for all MSO definable binary relations. 1

Rijke. PDL for ordered trees

This paper is about a special version of PDL, designed by Marcus Kracht for reasoning about sibling ordered trees. It has four basic programs corresponding to the child, parent, left- and right-sibling relations in such trees. The original motivation for this language is rooted in the field of model-theoretic syntax. Motivated by recent developments in the area of semistructured data, and, especially, in the field of query languages for XML (eXtensible Markup Language) documents, we revisit the language. This renewed interest comes with a special focus on complexity and expressivity aspects of the language, aspects that have so far largely been ignored. We survey and derive complexity results, and spend most of the paper on the most important open question concerning the language: what is its expressive power? We approach this question from two angles: Which first order properties can be expressed? And which second order properties? While we are still some way from definitive answers to these questions, we discuss two first order fragments of the PDL language for ordered trees, and show how the language can be used to express some typical (second order) problems, like the boolean circuit and the frontier problem.

PDL for ordered trees

This paper is about a special version of PDL, proposed by Marcus Kracht, for reasoning about sibling ordered trees. It has four basic programs corresponding to the child, parent, left- and right-sibling relations in such trees. The original motivation for this language is rooted in the field of model-theoretic syntax. Motivated by recent developments in the area of semi-structured data, and, especially, in the field of query languages for XML (eXtensible Markup Language) documents, we revisit the language. This renewed interest comes with a special focus on complexity and expressivity aspects of the language, aspects that have so far largely been ignored. We survey and derive complexity results, and spend most of the paper on the most important open question concerning the language: what is its expressive power? We approach this question from two angles: Which first-order properties can be expressed? And which second-order properties? While we are still some way from definitive answers to these questions, we discuss two first-order fragments of the PDL language for ordered trees, and show how the language can be used to express some typical (second-order) problems, like the boolean circuit and the frontier problem