Online Exploration of Polygons with Holes

We study online strategies for autonomous mobile robots with vision to explore unknown polygons with at most h holes. Our main contribution is an (h+c_0)!-competitive strategy for such polygons under the assumption that each hole is marked with a special color, where c_0 is a universal constant. The strategy is based on a new hybrid approach. Furthermore, we give a new lower bound construction for small h.Comment: 16 pages, 9 figures, submitted to WAOA 201

The Influence of the EU Environmental Management and Auditing Scheme on Environmental Innovations and Competitiveness in Germany: An Analysis on the Basis of Case Studies and a Large-Scale Survey

This paper investigates the effects of the EU Environmental Management and Auditing Scheme (EMAS) on environmental innovations and competitiveness in German facilities. It comprises twelve in-depth case studies and telephone interviews with 1277 EMAS-validated facilities. The surveys show a positive influence of EMAS on environmental organisational, process and product innovations. Moreover, the environmental report supports the diffusion of environmental innovations. The econometric analysis with binary probit models shows a significant positive impact of the maturity of environmental management systems on environmental innovations. Another determinant of environmental innovations is the strong participation of specific departments in further development of EMAS, especially of the R&D department. An effect of strategic importance of EMAS on market success could not be confirmed. Facilities with high learning processes by environmental management systems however have a significantly better performance concerning turnover and exports. --Environmental management systems,environmental innovation,technological progress,cleaner production

Adult nutrition and butterfly fitness: effects of diet quality on reproductive output, egg composition, and egg hatching success

<p>Abstract</p> <p>Background</p> <p>In the Lepidoptera it was historically believed that adult butterflies rely primarily on larval-derived nutrients for reproduction and somatic maintenance. However, recent studies highlight the complex interactions between storage reserves and adult income, and that the latter may contribute significantly to reproduction. Effects of adult diet were commonly assessed by determining the number and/or size of the eggs produced, whilst its consequences for egg composition and offspring viability were largely neglected (as is generally true for insects). We here specifically focus on these latter issues by using the fruit-feeding tropical butterfly <it>Bicyclus anynana</it>, which is highly dependent on adult-derived carbohydrates for reproduction.</p> <p>Results</p> <p>Adult diet of female <it>B. anynana </it>had pronounced effects on fecundity, egg composition and egg hatching success, with butterflies feeding on the complex nutrition of banana fruit performing best. Adding vitamins and minerals to a sucrose-based diet increased fecundity, but not offspring viability. All other groups (plain sucrose solution, sucrose solution enriched with lipids or yeast) had a substantially lower fecundity and egg hatching success compared to the banana group. Differences were particularly pronounced later in life, presumably indicating the depletion of essential nutrients in sucrose-fed females. Effects of adult diet on egg composition were not straightforward, indicating complex interactions among specific compounds. There was some evidence that total egg energy and water content were related to hatching success, while egg protein, lipid, glycogen and free carbohydrate content did not seem to limit successful development.</p> <p>Conclusion</p> <p>The patterns shown here exemplify the complexity of reproductive resource allocation in <it>B. anynana</it>, and the need to consider egg composition and offspring viability when trying to estimate the effects of adult nutrition on fitness in this butterfly and other insects.</p

Vergleich unterschiedlicher Verfahren zur Einlungenventilation

Verschiedene Verfahren sind in der Vergangenheit entwickelt worden, um eine chirurgisch erwünschte Einlungenventilation bei verschiedenen operativen Eingriffen zu erzielen. Als Standard hat sich dabei die Verwendung eines Doppellumentubus etabliert. Der alternative Einsatz eines Bronchusblockers scheint in der täglichen Praxis häufig nur speziellen Situationen wie dem Vorliegen eines schwierigen Atemweges vorbehalten zu sein. In unserer prospektiv randomisierten Studie wurde die Anwendung des Doppellumentubus mit zwei Bronchusblockern (Arndt- und EZ-Blocker) verglichen. Die Studie wurde nach Genehmigung durch die Ethikkommssion des Saarlandes an 90 erwachsenen Patienten durchgeführt, die sich thoraxchirurgischen Eingriffen unterzogen. In 3 Gruppen von je 30 Patienten verglichen wir dabei die 3 Verfahren zur Atemwegstrennung hinsichtlich Platzierungszeit, Dislokationshäufigkeit und Qualität des Lungenkollapses. In unserer Studie zeigte sich, dass der EZ-Blocker dem Doppellumentubus hinsichtlich der benötigten Platzierungszeit zumindest ebenbürtig war (EZ 185 ± 64 sec vs. DLT 194 ± 117 sec), tendenziell perioperativ seltener dislozierte (EZ Gruppe bei 10 von 30 Patienten vs. DLT Gruppe bei 18 von 30 Patienten) und bei Dislokation signifikant schneller zu repositionieren war (EZ-Blocker 18 ± 12 sec vs. DLT 119 ± 162 sec). Der Arndt-Blocker benötigte hingegen im Vergleich deutlich längere Platzierungszeiten (Arndt-Blocker 393 ± 243 sec). Kein signifikanter Unterschied zwischen den 3 Verfahren fand sich bei der Qualität des erzielten Lungenkollapses. Die häufigere Anwendung des EZ-Blockers zur Herstellung einer Einlungenventilation scheint somit für die tägliche Praxis ein vielversprechender Ansatz zu sein und sollte in weiteren Studien untersucht werden.In the past decades, different devices have been developed to provide intraoperative one lung ventilation (OLV) in various operations when demanded by the surgeon. The most frequently chosen devices for this purpose are by far double lumen tubes (DLT). Using bronchial blockers (BB) as an alternative approach seems to be somehow limited to special situations such as difficult airways. In our prospective randomized trial we compared the use of DLT with two types of BB: the Arndt blocker and the EZ blocker. After approval by the local ethical committee, the study was performed on 90 patients who were scheduled to thoracic surgery requiring OLV. We compared the performance of the devices in terms of time for tube placement, frequency of device dislocation, and quality of achieved lung collapse using three groups of 30 subjects each. In our study, EZ blockers at least equaled DLT in time for tube placement (EZ 185 ± 64 sec vs DLT 194 ± 117 sec) were less prone to intraoperative dislocation (EZ 10 out of 30 patients, DLT 18 out of 30 patients), and repositioning after dislocation was significantly faster (EZ 18 ± 12 sec vs. DLT 119 ± 162 sec) Placement of Arndt blockers took a significantly longer time (393 ± 243 sec). No significant difference was found in the quality of lung collapse achieved by either of the three devices. Using the EZ blocker on a regular base to achieve OLV when necessary seems to be a promising approach and should be evaluated by further studies