Gaussian state entanglement witnessing through lossy compression

We propose a method to witness entanglement between two continuous-variable systems in a Gaussian state. Its key ingredient is a local lossy state transfer from the original spatially separated systems onto two spatially separated qubits. The qubits are initially in a pure product state, therefore by detecting entanglement between the qubits we witness entanglement between the two original systems. This method greatly simplifies entanglement witnessing in complex systems.Comment: 5 pages, 2 figure

High validity entanglement verification with finite copies of a quantum state

Detecting entanglement of multipartite quantum states is an inherently probabilistic process due to a finite number of measured samples. The level of confidence of entanglement detection can be used to quantify the probability that the measured signal is coming from a separable state and provides a meaningful figure of merit for big data sets. Yet, for limited sample sizes, to avoid serious misinterpretations of the experimental results, one should not only consider the probability that a separable state gave rise to the measured signal, but should also include information about the probability that the signal came from an entangled state. We demonstrate this explicitly and propose a comprehensive method of entanglement detection when only a very limited amount of data is available. The method is based on a non-linear combination of correlation functions and is independent of system size. As an example, we derive the optimal number of measurement settings and clicks per setting revealing entanglement with only 20 copies of a state.Comment: 13 pages, 4 figure

Talk, text, tag? Understanding self-annotation of smart home data from a user’s perspective

Delivering effortless interactions and appropriate interventions through pervasive systems requires making sense of multiple streams of sensor data. This is particularly challenging when these concern people’s natural behaviours in the real world. This paper takes a multidisciplinary perspective of annotation and draws on an exploratory study of 12 people, who were encouraged to use a multi-modal annotation app while living in a prototype smart home. Analysis of the app usage data and of semi-structured interviews with the participants revealed strengths and limitations regarding self-annotation in a naturalistic context. Handing control of the annotation process to research participants enabled them to reason about their own data, while generating accounts that were appropriate and acceptable to them. Self-annotation provided participants an opportunity to reflect on themselves and their routines, but it was also a means to express themselves freely and sometimes even a backchannel to communicate playfully with the researchers. However, self-annotation may not be an effective way to capture accurate start and finish times for activities, or location associated with activity information. This paper offers new insights and recommendations for the design of self-annotation tools for deployment in the real world

Tau protein liquid–liquid phase separation can initiate tau aggregation

Abstract The transition between soluble intrinsically disordered tau protein and aggregated tau in neurofibrillary tangles in Alzheimer's disease is unknown. Here, we propose that soluble tau species can undergo liquid–liquid phase separation (LLPS) under cellular conditions and that phase‐separated tau droplets can serve as an intermediate toward tau aggregate formation. We demonstrate that phosphorylated or mutant aggregation prone recombinant tau undergoes LLPS, as does high molecular weight soluble phospho‐tau isolated from human Alzheimer brain. Droplet‐like tau can also be observed in neurons and other cells. We found that tau droplets become gel‐like in minutes, and over days start to spontaneously form thioflavin‐S‐positive tau aggregates that are competent of seeding cellular tau aggregation. Since analogous LLPS observations have been made for FUS, hnRNPA1, and TDP43, which aggregate in the context of amyotrophic lateral sclerosis, we suggest that LLPS represents a biophysical process with a role in multiple different neurodegenerative diseases

High-Resolution Imaging and Multiparametric Characterization of Native Membranes by Combining Confocal Microscopy and an Atomic Force Microscopy-Based Toolbox

ISSN:1936-0851ISSN:1936-086