Image preference estimation with a data-driven approach: A comparative study between gaze and image features

Understanding how humans subjectively look at and evaluate images is an important task for various applications in the field of multimedia interaction. While it has been repeatedly pointed out that eye movements can be used to infer the internal states of humans, not many successes have been reported concerning image understanding. We investigate the possibility of image preference estimation based on a person’s eye movements in a supervised manner in this paper. A dataset of eye movements is collected while the participants are viewing pairs of natural images, and it is used to train image preference label classifiers. The input feature is defined as a combination of various fixation and saccade event statistics, and the use of the random forest algorithm allows us to quantitatively assess how each of the statistics contributes to the classification task. We show that the gaze-based classifier had a higher level of accuracy than metadata-based baseline methods and a simple rule-based classifier throughout the experiments. We also present a quantitative comparison with image-based preference classifiers and discuss the potential and limitations of the gaze-based preference estimator

Structural basis of Sec-independent membrane protein insertion by YidC

[プレスリリース]バイオサイエンス研究科膜分子複合機能学研究室の塚崎智也准教授らの研究グループが、タンパク質を細胞膜に組み込むメカニズムを解明しました（2014/04/17）Newly synthesized membrane proteins must be accurately inserted into the membrane, folded and assembled for proper functioning. The protein YidC inserts its substrates into the membrane, thereby facilitating membrane protein assembly in bacteria; the homologous proteins Oxa1 and Alb3 have the same function in mitochondria and chloroplasts, respectively1, 2. In the bacterial cytoplasmic membrane, YidC functions as an independent insertase and a membrane chaperone in cooperation with the translocon SecYEG3, 4, 5. Here we present the crystal structure of YidC from Bacillus halodurans, at 2.4 Å resolution. The structure reveals a novel fold, in which five conserved transmembrane helices form a positively charged hydrophilic groove that is open towards both the lipid bilayer and the cytoplasm but closed on the extracellular side. Structure-based in vivo analyses reveal that a conserved arginine residue in the groove is important for the insertion of membrane proteins by YidC. We propose an insertion mechanism for single-spanning membrane proteins, in which the hydrophilic environment generated by the groove recruits the extracellular regions of substrates into the low-dielectric environment of the membrane

SecY-SecA fusion protein retains the ability to mediate protein transport.

In bacteria, the membrane protein complex SecY/E/G and SecA ATPase are essential for protein translocation. About 30% of newly synthesized proteins in the cytosol are targeted to and translocated across the cytoplasmic membrane by the Sec factors. Although a number of single-molecule analyses and structural studies, including the crystal structure of SecYEG complexed with SecA, have been published, the underlying molecular mechanisms and the functional oligomer states remain elusive. In this study, we constructed a fusion protein SecY-SecA, which induces the formation of the SecY-A/SecE/SecG complex (SecYAEG), to enable investigation of the molecular mechanisms by advanced single-molecule analyses. SecYAEG-reconstituted liposomes were found to possess protein translocation activity in vitro and form stable intermediates capable of the translocation using a mutant substrate protein. We additionally found that one unit of SecYAEG complex embedded into a nanodisc, using membrane scaffold proteins, interacts strongly with the substrate. The isolated SecYAEG-reconstituted nanodisc is a promising tool for investigation of the molecular mechanisms by which a single unit of Sec machinery mediates protein translocation

Influence of road environmental elements on pedestrian and cyclist road crossing behaviour

The pedestrian and cyclist-related accident fatality rate is higher than that of other traffic accidents. One of the pedestrian behaviours that leads to traffic accidents is the act of moving rapidly onto the road from a blind spot without warning. Expert drivers practice hazard-anticipatory driving and will naturally seek to reduce uncertainty by attempting to fit their current driving context into a pre-existing category. Risk management is the process of identifying hazards and assessing and controlling risks to attain safety. The purpose of this study was to evaluate the influence that driving context-altering road environmental elements exert on the road-crossing behaviour of pedestrians and cyclists. Thus, this study attempted to identify covert hazards (obscured pedestrians and cyclists). A logistic regression analysis was employed along with data from the near-miss incident database, in which approximately 140,000 near-crash-relevant events were registered in 2017. By using the logistic regression analysis along with the annotations recorded in the database, we constructed a predictive model to identify covert hazards. The study demonstrated the feasibility of using a set of environmental elements that shape the driving context to construct a predictive model that identifies covert hazards

Protein translocation activity of the SecYAEG complex embedded in liposomes.

<p>A, Purified SecYAEG complex analyzed by SDS-PAGE and Coomassie Brilliant Blue staining; B, Protein translocation assay using SecYAEG-reconstituted or SecYEG-reconstituted liposomes in the presence or absence of SecA ATPase; protease-resistant translocated substrate, proOmpA-His₆-Myc, was detected by anti-Myc immunoblotting. C, Schematic depiction of the protein translocation systems <i>in vitro</i>.</p

Detection of protein translocation intermediate derived from SecYAEG-reconstituted liposomes and proOmpA(L59) mutant.

<p>The intermediate states were generated using proOmpA(L59) mutant. The protease-resistant region of proOmpA in the intermediate states was detected by newly obtained anti-proOmpA_38-54 immunoblotting under non-reducing conditions. Translocation was re-initiated upon addition of DTT, a reductant.</p

Stable complex of SecYAEG-reconstituted nanodisc and proOmpA.

<p>A, The mixture of SecYAEG-reconstituted nanodisc and proOmpA(L59) or proOmpA(L59)-sfGFP mutants, containing a disulfide loop nontranslocatable though the SecYEG, was analyzed by native PAGE and Coomassie Brilliant Blue staining. These bands were interpreted as stable complexes of SecYAEG-reconstituted nanodiscs with or without proOmpA. The upshifted bands were unaffected by the presence or absence of ATP. Schematic diagrams of the prepared proteins are shown. B, The upshifted bands were not detected using a signal peptide mutant proOmpA, 3Q, or SecYEG-reconstituted nanodisc instead of SecYAEG-reconstituted nanodisc.</p

Automatic Detection Method of Lane-Changing Intentions Based on Relationship with Adjacent Vehicles Using Artificial Potential Fields

This paper presents a new method to detect lane changes of other vehicles automatically. The main contribution of this work is to propose a new feature using a potential field that changes the distribution depending on the relative number of adjacent vehicles. Previous researches have considered only some of limited situations, for example, that the preceding vehicle is slower than the target vehicle. Therefore, degradation of the detection performance can occur under conditions that were not considered. On the other hand, the new feature we propose is able to describe general lane-changing situations by applying a dynamic potential model. We trained an estimation model and evaluated the performance using a traffic dataset with over 900 lane changes. It was confirmed that the proposed method outperforms previous methods in terms of both accuracy and early detection