Exact and Approximation Algorithms for Routing a Convoy Through a Graph

We study routing problems of a convoy in a graph, generalizing the shortest path problem (SPP), the travelling salesperson problem (TSP), and the Chinese postman problem (CPP) which are all well-studied in the classical (non-convoy) setting. We assume that each edge in the graph has a length and a speed at which it can be traversed and that our convoy has a given length. While the convoy moves through the graph, parts of it can be located on different edges. For safety requirements, at all time the whole convoy needs to travel at the same speed which is dictated by the slowest edge on which currently a part of the convoy is located. For Convoy-SPP, we give a strongly polynomial time exact algorithm. For Convoy-TSP, we provide an O(log n)-approximation algorithm and an O(1)-approximation algorithm for trees. Both results carry over to Convoy-CPP which - maybe surprisingly - we prove to be NP-hard in the convoy setting. This contrasts the non-convoy setting in which the problem is polynomial time solvable

3D-printed rotating spinnerets create membranes with a twist

Round hollow fiber membranes are long-established in applications such as gas separation, ultrafiltration and blood dialysis. Yet, it is well known that geometrical topologies can introduce secondary ow patterns counteracting mass transport limitations, stemming from diffusion resistances and fouling. We present a new systematic method- ology to fabricate novel membrane architectures. We use the freedom of design by 3D-printing spinnerets, having multiple bore channels of any geometry. First, such spinnerets are stationary to fabricate straight bore channels inside a monolithic membrane. Second, in an even more complex design, a new mechanical system enables rotating the spinneret. Such rotating multibore spinnerets enable (A) the preparation of twisted channels inside a porous monolithic membrane as well as (B) a helical twist of the outside geometry. The spun material systems comprise classical polymer solutions as well as metal-polymer slurries resulting in solid porous metallic monolithic membrane after thermal post-processing. It is known that twisted spiral-type bore channel geometries are potentially superior over straight channels with respect to mass and heat polarization phenomena, however their fabrication was cumber- some in the past. Now, the described methodology enables membrane fabrication to tailor the membrane geometry to the needs of the membrane process

Seroprevalence of mucosal and cutaneous human papillomavirus (HPV) types among children and adolescents in the general population in Germany

Background In Germany, HPV vaccination of adolescent girls was introduced in 2007. Nationally representative data on the distribution of vaccine-relevant HPV types in the pre-vaccination era are, however, only available for the adult population. To obtain data in children and adolescents, we assessed the prevalence and determinants of serological response to 16 different HPV types in a representative sample of 12,257 boys and girls aged 1–17 years living in Germany in 2003–2005. Methods Serum samples were tested for antibodies to nine mucosal and seven cutaneous HPV types. The samples had been collected during the nationally representative German Health Interview and Examination Survey for Children and Adolescents in 2003–2006. We calculated age- and gender-specific HPV seroprevalence. We used multivariable regression models to identify associations between demographic and behavioral characteristics and HPV seropositivity. Results We found low but non-zero seroprevalence for the majority of tested HPV types among children and adolescents in Germany. The overall seroprevalence of HPV-16 was 2.6%, with slightly higher values in adolescents. Seroprevalence of all mucosal types but HPV-6 ranged from 0.6% for HPV-33, to 6.4% for HPV-31 and did not differ by gender. We found high overall seroprevalence for HPV-6 with 24.8%. Cutaneous HPV type seroprevalence ranged from 4.0% for HPV-38 to 31.7% for HPV-1. In the majority of cutaneous types, seroprevalence did not differ between boys and girls, but increased sharply with age, (e.g., HPV-1 from 1.5% in 1–3-years-old to 45.1% in 10–11-years-old). Associations between behavioral factors and type-specific HPV prevalence were determined to be heterogeneous. Conclusions We report the first nationally representative data of naturally acquired HPV antibody reactivity in the pre-HPV-vaccination era among children and adolescents living in Germany. These data can be used as baseline estimates for evaluating the impact of the current HPV vaccination strategy targeting 9–14-years-old boys and girls.Peer Reviewe

High-repetition-rate and high-photon-flux 70 eV high-harmonic source for coincidence ion imaging of gas-phase molecules

Unraveling and controlling chemical dynamics requires techniques to image structural changes of molecules with femtosecond temporal and picometer spatial resolution. Ultrashort-pulse x-ray free-electron lasers have significantly advanced the field by enabling advanced pump-probe schemes. There is an increasing interest in using table-top photon sources enabled by high-harmonic generation of ultrashort-pulse lasers for such studies. We present a novel high-harmonic source driven by a 100 kHz fiber laser system, which delivers 10$^{11}$ photons/s in a single 1.3 eV bandwidth harmonic at 68.6 eV. The combination of record-high photon flux and high repetition rate paves the way for time-resolved studies of the dissociation dynamics of inner-shell ionized molecules in a coincidence detection scheme. First coincidence measurements on CH$_3$I are shown and it is outlined how the anticipated advancement of fiber laser technology and improved sample delivery will, in the next step, allow pump-probe studies of ultrafast molecular dynamics with table-top XUV-photon sources. These table-top sources can provide significantly higher repetition rates than the currently operating free-electron lasers and they offer very high temporal resolution due to the intrinsically small timing jitter between pump and probe pulses

Prognoseentscheidung zum Verschlechterungsverbot: Fachtechnische Arbeitshilfe zur Prognoseentscheidung hinsichtlich des ökologischen Zustands im Rahmen der Prüfung des Verschlechterungsverbots: Sächsische Arbeitshilfe Version 1.1

Die Prognose, ob ein Vorhaben an Gewässern gegen das Verschlechterungsverbot nach der EG-Wasserrahmenrichtlinie verstößt, gehört zu den herausfordernden Aufgaben von Vorhabensträgern und Wasserbehörden. Für 22 Fallgruppen werden die wichtigsten Vorhabenskategorien an Fließgewässern hinsichtlich ihrer Wirkfaktoren, abiotischen Wirkung und biotischen Auswirkungen bis hin zu den betroffenen Bewertungsmodulen für den ökologischen Zustand beschrieben. Vorkehrungen zur Minderung der Auswirkungen helfen, Verschlechterungen zu vermeiden oder Ausnahmegenehmigungen zu ermöglichen. Redaktionsschluss: 11.03.202

Concept, Development and Testing of Mars Rover Prototypes for ESA Planetary Exploration

This paper presents the system architecture and design of two planetary rover laboratory prototypes developed at the European Space Agency (ESA). These research platforms have been developed to provide early prototypes for validation of designs and serve ESA’s Automation & Robotics Lab infrastructure as testbeds for continuous research and testing. Both rovers have been built considering the constraints of Space Systems with the sufficient level of representativeness to allow rapid prototyping. They avoid strictly space-qualified components and designs that present a major cost burden and frequently lack the flexibility or modularity that the lab environment requires for its investigations. This design approach is followed for all the mechanical, electrical, and software aspects of the system. In this paper, two ExoMars mission-representative rovers, the ExoMars Testing Rover (ExoTeR) and the Martian Rover Testbed for Autonomy (MaRTA), are thoroughly described. The lessons learnt and experience gained while running several research activities and test campaigns are also presented. Finally, the paper aims to provide some insight on how to reduce the gap between lab R&D and flight implementation by anticipating system constraints when building and testing these platforms

Ethical, legal and social aspects of human cerebral organoids and their governance in Germany, the United Kingdom and the United States

Human cerebral organoids (HCOs) are model systems that enable researchers to investigate the human brain in ways that had previously been impossible. The emergence of HCOs was accompanied by both expert and layperson discussions concerning the possibility of these novel entities developing sentience or consciousness. Such concerns are reflected in deliberations about how to handle and regulate their use. This perspective article resulted from an international and interdisciplinary research retreat “Ethical, Legal and Social Aspects of Human Cerebral Organoids and their Governance in Germany, the United Kingdom and the United States”, which took place in Tübingen, Germany, in August 2022. The retreat focused on whether HCO research requires new ethical and regulatory approaches. It addressed epistemic issues around the detection and theorisation of consciousness, ethical concerns around moral status and research conduct, difficulties for legislation and guidelines managing these entities, and public engagement

Sheep Updates 2005 - Part 4

This session covers twelve papers from different authors: REPRODUCTION 1. Is it worth increasing investment to increase lambing percentages? Lucy Anderton Department of Agriculture Western Australia. 2. What value is a lamb? John Young, Farming Systems Analysis Service, Kojonup, WA 3. Providing twin-bearing ewes with extra energy at lambing produces heavier lambs at marking. Rob Davidson WAMMCO International,, formerly University of Western Australia; Keith Croker, Ken Hart, Department of Agriculture Western Australia, Tim Wiese, Chuckem , Highbury, Western Australia. GENETICS 4. Underlying biological cause of trade-off between meat and wool. Part 1. Wool and muscle glycogen, BM Thomson, I Williams, University of WA, Crawley, JRBriegel, CSIRO Livestock Industries, Floreat Park WA &CRC for the Australian Sheep Industry, JC Greeff, Department of Agriculture Western Australia &CRC for the Australian Sheep Industry. 5. Underlying biological cause of trade-off between meat and wool. Part 2. Wool and fatness, NR Adams1,3, EN Bermingham1,3, JR Briegel1,3, JC Greeff2,3 1CSIRO Livestock Industries, Floreat Park WA 2Department of Agriculture Western Australia, 3CRC for the Australian Sheep Industry 6. Genetic trade-offs between lamb and wool production in Merino breeding programs, Johan Greeff, Department of Agriculture, Western Australia. 7. Clean fleece weight is no phenotypically independent of other traits. Sue Hatcherac and Gordon Refshaugebc aNSWDPI Orange Agricultural Institute, Orange NSW 2800 bUNE c/- NSWDPI Cowra AR&AS Cowra NSW 2794 cAustralian Sheep Industry CRC. 8. When you\u27re on a good thing, do it better: An economic analysis of sheep breed profitability. Emma Kopke, Ross Kingwell, Department of Agriculture, Western Australia, John Young, Farming Systems Analysis Service, Kojonup, WA. 9. Selection Demonstration Flocks: Demonstrating improvementsin productivity of merinos, K.E. Kemper, M.L. Hebart, F.D. Brien, K.S. Jaensch, R.J. Grimson, D.H. Smith South Australian Research and Development Institute 10. You are compromising yield by using Dust Penetration and GFW in breeding programs, Melanie Dowling, Department of Agriculture, Western Australia, A. (Tony) Schlink, CSIRO Livestock Industries, Wembley, Johan Greeff, Department of Agriculture Western Australia. 11. Merino Sheep can be bred for resistance to breech strike. Johan Greeff , John Karlsson, Department of Agriculture Western Australia 12. Parasite resistant sheep and hypersensitivity diarrhoea, L.J.E. Karlsson & J.C. Greeff, Department of Agriculture Western Australi

Diversity of Antibiotic-Active Bacteria Associated with the Brown Alga Laminaria saccharina from the Baltic Sea

Bacteria associated with the marine macroalga Laminaria saccharina, collected from the Kiel Fjord (Baltic Sea, Germany), were isolated and tested for antimicrobial activity. From a total of 210 isolates, 103 strains inhibited the growth of at least one microorganism from the test panel including Gram-negative and Gram-positive bacteria as well as a yeast. Most common profiles were the inhibition of Bacillus subtilis only (30%), B. subtilis and Staphylococcus lentus (25%), and B. subtilis, S. lentus, and Candida albicans (11%). In summary, the antibiotic-active isolates covered 15 different activity patterns suggesting various modes of action. On the basis of 16S rRNA gene sequence similarities >99%, 45 phylotypes were defined, which were classified into 21 genera belonging to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Phylogenetic analysis of 16S rRNA gene sequences revealed that four isolates possibly represent novel species or even genera. In conclusion, L. saccharina represents a promising source for the isolation of new bacterial taxa and antimicrobially active bacteria