A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2020; you can also visit the original URL.
The file type is
A physical experiment comprises along the time trajectory a start, a time evolution (duration), and an end, which is the measurement. In non relativistic quantum mechanics the start of the experiment is defined by the wave function at time 0 taking into account the starting conditions, the evolution is described by the wave function following the Schr\"odinger equation and the measurement by the Born rule. While the Schr\"odinger equation is deterministic, it is the Born rule that makes quantumarXiv:1901.03663v1 fatcat:nwtwocy2djd5zkc4uyak6wzi64
more »... mechanics statistical with all its consequences. The nature of the Born rule is thereby unknown albeit necessary since it produces the correct ensemble averaged measures of the experiment. Here, it is demonstrated that the origin of the Born rule is the projection from the quantum frame (i.e. wave description) to the classical mechanics frame (i.e. particle description) described by a Ehrenfest theorem-oriented Fourier transformation. The statistical averaging over many measurements is necessary in order to eliminate the unknown initial and end time coordinate of the experiment in reference to the beginning of the universe.
As a consequence of a discrete time, entropy emerges (Riek, 2014) connecting causality and entropy to each other. ...doi:10.3390/e22060647 pmid:33286419 pmcid:PMC7517184 fatcat:tui67t6k6nd6xozjboc6vp6daq
Shuffle projection is motivated by the verification of safety properties of special parameterized systems. Basic definitions and properties, especially related to alphabetic homomorphisms, are presented. The relation between iterated shuffle products and shuffle projections is shown. A special class of multi-counter automata is introduced, to formulate shuffle projection in terms of computations of these automata represented by transductions. This reformulation of shuffle projection leads toarXiv:1503.08602v1 fatcat:uwu4smbkizenxdppv4zrfg5no4
more »... struction principles for pairs of languages closed under shuffle projection. Additionally, it is shown that under certain conditions these transductions are rational, which implies decidability of closure against shuffle projection. Decidability of these conditions is proven for regular languages. Finally, without additional conditions, decidability of the question, whether a pair of regular languages is closed under shuffle projection, is shown. In an appendix the relation between shuffle projection and the shuffle product of two languages is discussed. Additionally, a kind of shuffle product for computations in S-automata is defined.
Interactions between biological membranes and disease-associated amyloids are well documented and their prevalence suggests that an inherent affinity exists between these two distinct molecular assemblies. Within the framework of our research project on amyloids and the origins of life, we hypothesized here that such interactions could increase both the sequence and structure space of peptide amyloids in a heterogeneous system and that if cooperative in nature, the interaction could bedoi:10.1101/323030 fatcat:uxcm5fyxlfcwzcf6gcjxwq5j54
more »... ous to the propagation of these entities in a prebiotic context. Thus, we have investigated the interplay between vesicle-forming fatty acids and amyloidogenic peptides, the respective precursors of lipids and proteins. Individually they are able to form ordered structures under a limited range of conditions with the bilayer of fatty acid vesicles and the cross-β core of amyloids both being repetitive structures that could in principle support a cooperative interaction. Here we report that an 8-residue basic peptide that can form an amphipathic β-strand, that is soluble at neutral pH and that can form amyloids above its pI at pH 11, is also able to cooperatively form novel co-aggregates of diverse structure with and in the context of simple fatty acids at neutral pH. Below the critical vesicle concentration (CVC) the mixtures of fatty acid and peptide yield a flocculent precipitate with an underlying β-structure. Above the CVC, the mixtures yield ribbon or tube-like structures that bear some of the hallmarks of amyloids yet have associated with them a significant amount of fatty acids, likely in a bilayer structure. In the context of the origin of cellular life these results expand the phase space of both peptides and fatty acids while providing a simple yet robust physical connection between two distinct biological entities relevant for life.
In vitro, distinct fold structures can result Neurodegeneration A protein's structure used to diagnose disease Juan Atilio Gerez & Roland Riek Parkinson's disease and multiple system atrophy involve ... Juan Atilio Gerez and Roland Riek are in the Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, 8093 Zurich, Switzerland. e-mails: firstname.lastname@example.org; roland.riek ...doi:10.1038/d41586-020-00131-3 pmid:32042086 fatcat:6b7u3rm3nbgfjijnnplohsckzi
Despite extensive research, a detailed description of the physiological function of α-Synuclein (α-Syn), the human neuronal protein involved in the pathogenesis of Parkinson's Disease, is still lacking, most likely due to its highly dynamic conformation and behaviour. Recently, it has become increasingly evident that the interaction of α-Syn with membranes plays an important role in its function and misfunction. Strikingly, despite not having a membrane scaffolding domain, α-Syn can extensivelydoi:10.29245/2572.942x/2016/3.1031 fatcat:2gnn3sgcgjaezjk4wdkhmen3du
more »... reshape membrane bilayers. Moreover, stable and soluble nanometer-sized particles, whose morphology is ranging from tubules to discoids, can be obtained in vitro with different protocols and from different lipids. The focus of this review article is on the description of the membrane remodelling activity of α-Syn and on its possible physiological role.
Lecture Notes in Computer Science
Rieke and Z. ... Rieke ...doi:10.1007/978-3-642-14706-7_25 fatcat:uxa3jaaj3ngg3bphwxgoxbmhcq
Communications in Computer and Information Science
Security needs to be aligned with business". Business situational awareness is the ability to continually monitor ongoing actions and events related to business operations and estimate the immediate and close-future impact of the new information. This ability is crucial for business continuity and should encompass all associated aspects. Considering the growing dependability of businesses on IT on the one hand, and ever increasing threats on the other, IT security aspects should get adequatedoi:10.1007/978-3-319-25360-2_9 fatcat:b3nvbvkyynfvbcycaobddrbz2q
more »... ention in the awareness system. We present an approach to raise business situational awareness using an advanced method of predictive security analysis at runtime. It continually observes a system's event stream to find deviations from specified behavior and violations of security compliance rules. Operational models of the key processes are utilized to predict critical security states, evaluate possible countermeasures, and trigger corrective actions. A security information model maintains the security strategy and explains possible deviations from the originating goal. The approach is demonstrated on an industrial scenario from a European research project.
(From Greenwald and Riek 2010; reprinted, with permission, from Elsevier # 2010.) ... Finally, it has been suggested that a polymorph may even appear at the amino acid residue side-chain level (Greenwald and Riek 2010) . ...doi:10.1101/cshperspect.a023572 pmid:27793967 fatcat:zj2rhusbvrcqpncxrknmjjovk4
Edited by Per Hammarström a b s t r a c t Protein aggregation is a process in which proteins self-associate into imperfectly ordered macroscopic entities. Such aggregates are generally classified as either amorphous or highly ordered, the most common form of the latter being amyloid fibrils. Amyloid fibrils composed of cross-b-sheet structure are the pathological hallmarks of several diseases including Alzheimer's disease, but are also associated with functional states such as the fungal HET-sdoi:10.1016/j.febslet.2009.07.003 pmid:19596006 fatcat:4qhnbhnxvrds3jindheo2fgx5q
more »... rion. This review aims to summarize the recent high-resolution structural studies of amyloid fibrils in light of their (potential) activities. We propose that the repetitive nature of the cross-b-sheet structure of amyloids is key for their multiple properties: the repeating motifs can translate a rather non-specific interaction into a specific one through cooperativity.
Journal of Physical Chemistry & Biophysics
Table 1 : 1 Limit of ΔS as N approaches infinity at constant ratio M N Citation: Riek R, Sobol A (2016) Comments on the Extensivity of the Boltzmann Entropy. ... An alternative to the Boltzmann entropy In the request for an alternative microscopic description of the thermodynamic entropy we would like to refer the reader to the recently introduced concept by Riek ...doi:10.4172/2161-0398.1000207 fatcat:4rijfxka7bcilowgje7tc25gre
Causality describes the process and consequences from an action: a cause has an effect. Causality is preserved in classical physics as well as in special and general theories of relativity. Surprisingly, causality as a relationship between the cause and its effect is in neither of these theories considered a law or a principle. Its existence in physics has even been challenged by prominent opponents in part due to the time symmetric nature of the physical laws. With the use of the reduceddoi:10.3390/e23091212 pmid:34573836 fatcat:6djdnrdjhbatbosj4j6fqzddai
more »... and the least action principle of Maupertuis along with a discrete dynamical time physics yielding an arrow of time, causality is defined as the partial spatial derivative of the reduced action and as such is position- and momentum-dependent and requests the presence of space. With this definition the system evolves from one step to the next without the need of time, while (discrete) time can be reconstructed.
doi:10.3389/fnhum.2016.00608 pmid:27994545 pmcid:PMC5133249 fatcat:5n6akp4s2vg3ddbdbhpisk45ta
Lecture Notes in Computer Science
The systematic protection of critical information infrastructures requires an analytical process to identify the critical components and their interplay, to determine the threats and vulnerabilities, to assess the risks and to prioritise countermeasures where risk is unacceptable. This paper presents an integrated framework for model-based symbolic interpretation, simulation and analysis with a comprehensive approach focussing on the validation of network security policies. A graph of alldoi:10.1007/11962977_6 fatcat:fij2wsv5anapdcwb4kum2cq4dy
more »... le attack paths is automatically computed from the model of an ICT network, of vulnerabilities, exploits and an attacker strategy. Constraints on this graph are given by a model of the network security policy. The impact of changes to security policies can be computed and visualised by finding differences in the attack graphs. A unique feature of the presented approach is, that abstract representations of these graphs can be computed that allow comparison of focussed views on the behaviour of the system. This guides optimal adaptation of the security policy to the given vulnerability setting.
Citation: Wang L, Maji SK, Sawaya MR, Eisenberg D, Riek R (2008) Bacterial inclusion bodies contain amyloid-like structure. ...doi:10.1371/journal.pbio.0060195 pmid:18684013 pmcid:PMC2494559 fatcat:7ach6ryzk5hsxbrsezfssemzri
« Previous Showing results 1 — 15 out of 578 results