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Blockchains can be used to build multi-player online games and virtual worlds that require no central server. This concept is pioneered by Huntercoin, but it leads to large growth of the blockchain and heavy resource requirements. In this paper, we present a new protocol inspired by payment channels and sidechains that allows for trustless off-chain interactions of players in private turn-based games. They are usually performed without requiring space in the public blockchain, but if a dispute arises, the public network can be used to resolve the conflict. We also analyze the resulting security guarantees and describe possible extensions to games with shared turns and for near real-time interaction. Our proposed concept can be used to scale Huntercoin to very large or even infinite worlds and to enable almost real-time interactions between players.

Intro -- Vorwort -- Vorbemerkung -- Inhaltsverzeichnis -- 1 Kryptoökonomie -- 2 Was sind Kryptotransaktionssysteme? -- 2.1 Hintergrund und philosophische Betrachtung -- 2.2 Definitionen -- 3 Aktuelle Daten zur Bitcoin-Ökosphäre -- 3.1 Google Trend-Analyse -- 3.2 Anzahl der Transaktionen pro Tag -- 3.3 Entwicklung des Wertes des bitcoin -- 3.4 Anzahl der Projekte auf GitHub -- 3.5 Anzahl der Wallets und Anzahl der Nutzer -- 3.6 Akzeptanz des bitcoins bei den Unternehmen -- 3.7 Akzeptanz beim Konsumenten -- 3.8 Venture-Capital -- 3.9 Bitcoin als Netzwerkgut -- 3.10 Zusammenfassung -- 4 Funktionsweise des Bitcoin-Netzwerks -- 4.1 Dezentralität und Digitalität des Systems -- 4.2 Bedeutung des angewandten Konsens-Algorithmus -- 4.3 (Pseudo-)Anonymität -- 4.4 Bitcoin-Clients und Wallets -- 4.5 Durchführung von Transaktionen im Netzwerk -- 4.6 Scripte -- 5 Vergleich zum herkömmlichen Finanzsystem -- 5.1 Grundfunktionen des Geldes -- 5.2 Die Geschichte des Geldes -- 5.3 Die historische Entwicklung der Geldtheorien -- 5.4 Entwicklung der Geldtheorien -- 5.5 Bedeutung dieser Entwicklungen für die Kryptowährungen -- 5.6 Komplementärwährungen -- 5.7 Trend zur bargeldlosen Gesellschaft -- 6 Innovationsbedarf bei den Finanzsystemen -- 7 Bitcoin als Zahlungsmittel -- 7.1 Globalität des Bitcoin-Netzwerks -- 7.2 Transaktionskostenthematik -- 7.3 Digitale Geschäftsmodelle und Mikrozahlungen -- 8 Limitationen des Bitcoin-Systems -- 8.1 Komplexität -- 8.2 Sicherheit -- 8.3 Skalierbarkeit des Systems -- 8.4 Lange Bestätigungszeiten -- 8.5 Transaktionskosten als Mining-Belohnung -- 8.6 Hoher Ressourcenverbrauch -- 8.7 Aufbau industrieller Miningkapazitäten -- 8.8 51-Prozent-Attacke -- 8.9 Wechselkursvolatilität -- 8.10 Deflation -- 9 Lösungsansätze für die Limitationen des Bitcoin-Systems -- 9.1 Altcoins (Alternative Kryptowährungen) -- 9.2 Sidechains.

The porosity of filters is typically fixed; thus, complex purification processes require application of multiple specialized filters. In contrast, smart filters with controllable and tunable properties enable dynamic separation in a single setup. Herein, an electroactive filter with controllable pore size is demonstrated. The electroactive filter is based on a metal mesh coated with a polythiophene polymer with ethylene glycol sidechains (p(g3T2)) that exhibit unprecedented voltage-driven volume changes. By optimizing the polymer coating on the mesh, controllable porosity during electrochemical addressing is achieved. The pores reversibly open and close, with a dynamic range of more than 95%, corresponding to over 30 mu m change of pores widths. Furthermore, the pores widths could be defined by applied potential with a 10 mu m resolution. From among hundreds of pores from different samples, about 90% of the pores could be closed completely, while only less than 1% are inactive. Finally, the electroactive filter is used to control the flow of a dye, highlighting the potential for flow control and smart filtration applications. ; Funding Agencies|Wallenberg Wood Science Center [KAW 2018.0452]; Swedish Research Council - VetenskapsradetSwedish Research Council [VR-2020-05045]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009-00971]; KAUSTKing Abdullah University of Science & Technology; EPSRCUK Research & Innovation (UKRI)Engineering & Physical Sciences Research Council (EPSRC) [EP/T026219/1]; European UnionEuropean Commission [952911, 862474, 101007084]

We present a robust protocol based on iterations of free energy perturbation (FEP) calculations, chemical synthesis, biophysical mapping and X‐ray crystallography to reveal the binding mode of an antagonist series to the A2A adenosine receptor (AR). Eight A2AAR binding site mutations from biophysical mapping experiments were initially analyzed with sidechain FEP simulations, performed on alternate binding modes. The results distinctively supported one binding mode, which was subsequently used to design new chromone derivatives. Their affinities for the A2AAR were experimentally determined and investigated through a cycle of ligand‐FEP calculations, validating the binding orientation of the different chemical substituents proposed. Subsequent X‐ray crystallography of the A2AAR with a low and a high affinity chromone derivative confirmed the predicted binding orientation. The new molecules and structures here reported were driven by free energy calculations, and provide new insights on antagonist binding to the A2AAR, an emerging target in immuno‐oncology ; This work was financially supported by the Swedish Research Council (Grant 521‐2014‐2118); Consellería de Cultura, Educación e Ordenación Universitaria of the Galician Government (Grant ED431B2017/70); Centro Singular de Investigación de Galicia accreditation 2016–2019 (Grant ED431G/09), and the European Regional Development Fund (ERDF). Additional support from the Swedish strategic research program eSSENCE is acknowledged. The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC). This research program has been developed in the frame of the European COST action ERNEST (Grant CA 18133) and GLISTEN (Grant CA 1207) ; SI

The porosity offilters is typicallyfixed; thus, complex purification processesrequire application of multiple specializedfilters. In contrast, smartfilters withcontrollable and tunable properties enable dynamic separation in a single setup.Herein, an electroactivefilter with controllable pore size is demonstrated. Theelectroactivefilter is based on a metal mesh coated with a polythiophene polymerwith ethylene glycol sidechains (p(g3T2)) that exhibit unprecedented voltage-driven volume changes. By optimizing the polymer coating on the mesh, con-trollable porosity during electrochemical addressing is achieved. The poresreversibly open and close, with a dynamic range of more than 95%, corre-sponding to over 30μm change of pores'widths. Furthermore, the pores'widthscould be defined by applied potential with a 10μm resolution. From amonghundreds of pores from different samples, about 90% of the pores could beclosed completely, while only less than 1% are inactive. Finally, the electroactivefilter is used to control theflow of a dye, highlighting the potential forflow controland smartfiltration applications. ; J.G. and V.K.O contributed equally to this work. This work was supported by The Wallenberg Wood Science Center (KAW 2018.0452), the Swedish Research Council—Vetenskapsrådet—VR-2020-05045, the Knut and Alice Wallenberg Foundation, and the Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No. 2009-00971). We also acknowledge financial support from KAUST, as well as from the European Union's Horizon 2020 research and innovation programme under grant agreement No.952911, project BOOSTER grant agreement No.862474, project RoLA-FLEX, grant agreement No.101007084, project CITYSOLAR as well as EPSRC Project EP/T026219/1

Generating the immune response requires the discrimination of peptides presented by the human leukocyte antigen complex (HLA) through the T-cell receptor (TCR). However, how a single amino acid substitution in the antigen bonded to HLA affects the response of T cells remains uncertain. Hence, we used molecular dynamics computations to analyze the molecular interactions between peptides, HLA and TCR. We compared immunologically reactive complexes with non-reactive and weakly reactive complexes. MD trajectories were produced to simulate the behavior of isolated components of the various p-HLA-TCR complexes. Analysis of the fluctuations showed that p-HLA binding barely restrains TCR motions, and mainly affects the CDR3 loops. Conversely, inactive p-HLA complexes displayed significant drop in their dynamics when compared with its free versus ternary forms (p-HLA-TCR). In agreement, the free non-reactive p-HLA complexes showed a lower amount of salt bridges than the responsive ones. This resulted in differences between the electrostatic potentials of reactive and inactive p-HLA species and larger vibrational entropies in non-elicitor complexes. Analysis of the ternary p-HLA-TCR complexes also revealed a larger number of salt bridges in the responsive complexes. To summarize, our computations indicate that the affinity of each p-HLA complex towards TCR is intimately linked to both, the dynamics of its free species and its ability to form specific intermolecular salt-bridges in the ternary complexes. Of outstanding interest is the emerging concept of antigen reactivity involving its interplay with the HLA head sidechain dynamics by rearranging its salt-bridges ; Financial support was provided by the Spanish Ministry of Economy and Competiveness (Grant No. BFU2012-31670/BMC); The Andalusian Government (Grant PAI, BIO198); The Spanish Fund for Health Research (FIS; code PI11/02366, FI12/00189) and the Ramón Areces Foundation. ; Peer reviewed

Managing the profusion of health data from either caregivers, patients and any other stakeholder institution in the health system leads to the creation of numerous databases which are rarely effectively coordinated with one another. In addition, the same information can be recorded several times by different parties, which is a source of many errors. In addition, such large databases are vulnerable to hacking and are subject to strict legal rules for controlling data confidentiality. The dramatic experience of the global Covid-19 pandemic has highlighted the great difficulty of effectively monitoring patients with existing information systems. Given this observation, it appears that the creation of a decentralized health blockchain with limited access is a solution to rationalize the management of health data while preserving the essential rules of confidentiality, scalability and traceability.

Managing the profusion of health data from either caregivers, patients and any other stakeholder institution in the health system leads to the creation of numerous databases which are rarely effectively coordinated with one another. In addition, the same information can be recorded several times by different parties, which is a source of many errors. In addition, such large databases are vulnerable to hacking and are subject to strict legal rules for controlling data confidentiality. The dramatic experience of the global Covid-19 pandemic has highlighted the great difficulty of effectively monitoring patients with existing information systems. Given this observation, it appears that the creation of a decentralized health blockchain with limited access is a solution to rationalize the management of health data while preserving the essential rules of confidentiality, scalability and traceability.

The development and design of future internal combustion engines requires fundamental understanding and the capability to model the autoignition and pollutant formation behavior of petroleum-based and other fuels. Naphthenes are an important constituent of gasoline, and they can comprise larger portions of unconventionally-derived gasoline. There is a lack of data and validated models for 5-membered ring naphthenes. In this work, the autoignition characteristics of cyclopentane, and two of its substituted analogues, methylcyclopentane, and ethylcyclopentane are investigated using a twin-piston rapid compression machine. Each fuel is studied at engine-representative conditions: 20, 50 bar and 700–980 K, with mixtures containing stoichiometric fuel/oxygen ratios at various extents of dilution with inert gases. Negative temperature coefficient (NTC) behavior is observed for cyclopentane, though first-stage ignition and associated low temperature heat release behavior are only evident at temperatures below that for the transition to NTC. Pressure is found to have a larger impact on the reactivity than oxygen dilution, with both effects amplified in the NTC region. The cyclopentane experiments in this study are challenged by the sensitivity of this molecule to non-uniform, or mild ignition phenomena within the NTC region. The addition of saturated sidechains in methyl- and ethylcyclopentane significantly increases the reactivity of the molecules, especially at low temperature and NTC conditions. At the highest temperatures though, there is little difference between the three naphthenes. Typical two-stage ignition behavior is observed across a wide range of temperatures for these alkyl cyclopentanes with no mild ignition observed within the NTC region. A recently developed model for cyclopentane is extended to include reactions for methylcyclopentane, and this is used to simulate the new experiments. The simulation results indicate that low temperature reactivity of cyclopentane is dominated by HO2 elimination of the RO2 species producing cyclopentene, and this inhibits autoignition since it is a very stable molecule. When a methyl group is substituted on the ring, additional RO2 isomerization pathways are available, and these substantially increase the fuel reactivity. HO2 elimination is also important with methylcyclopentane, and this leads to significant production of cyclic olefins which can further react to produce diolefins. These findings are consistent with observations that have been made in other experimental apparatuses. ; The submitted manuscript has been created in part by UChicago Argonne, LLC, Operator of Argonne National Laboratory ("Argonne"). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract no. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan. http://energy.gov/downloads/doe-public-access-plan. This work is performed under the auspices of the Office of Energy Efficiency and Renewable Energy, Office of Vehicle Technology, U.S. Department of Energy, under contract number DE-AC02-06CH11357. KAUST CCRC is grateful to Saudi Aramco for sponsoring this research under the FUELCOM program, and the Office of Sponsored Research (OSR) at KAUST under Award no. OSR-2016-CRG5-3022. The work at LLNL is supported by the U.S. Department of Energy, Vehicle Technologies Office (program managers Gurpreet Singh and Leo Breton) and performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The authors acknowledge the assistance of Jeffrey Santner and Toby Rockstroh for their efforts to maintain and operate ANL's tpRCM, Robert Tranter at ANL for helpful discussions, and Dr. Samah Mohamed and Mr. Tony Bissoonauth (KAUST) for help with the kinetic modeling.