RecipeMeta: Metapath-enhanced Recipe Recommendation on Heterogeneous Recipe Network

Recipe is a set of instructions that describes how to make food. It can help people from the preparation of ingredients, food cooking process, etc. to prepare the food, and increasingly in demand on the Web. To help users find the vast amount of recipes on the Web, we address the task of recipe recommendation. Due to multiple data types and relationships in a recipe, we can treat it as a heterogeneous network to describe its information more accurately. To effectively utilize the heterogeneous network, metapath was proposed to describe the higher-level semantic information between two entities by defining a compound path from peer entities. Therefore, we propose a metapath-enhanced recipe recommendation framework, RecipeMeta, that combines GNN (Graph Neural Network)-based representation learning and specific metapath-based information in a recipe to predict User-Recipe pairs for recommendation. Through extensive experiments, we demonstrate that the proposed model, RecipeMeta, outperforms state-of-the-art methods for recipe recommendation

Spatio-temporal chaos of one-dimensional thin elastic layer with the rate-and-state friction law

The rate-and-state friction (RSF) law is an empirical law often used to model the behavior of rock friction and reproduce the behavior of earthquakes. Recently, the model has been expanded to include so-called slow earthquakes, which are observed at the margins between steadily sliding aseismic and seismogenic zones. In this study, we incorporate the RSF law into a one-dimensional elastic layer spanned perpendicular to the loading direction as a model for the marginal area between aseismic and seismogenic zones. We obtained the complex Ginzburg-Landau equation near a Hopf bifurcation, and showed that the system has Benjamin-Fair instability, leading to spatio-temporal chaos. We conducted numerical calculations near the Hopf bifurcation point, and showed that an irregular oscillation appears when parameters with Benjamin-Feir instability are employed. The size of slip event showed an exponential distribution that resembles a type of slow earthquake.Comment: 33 pages, 7 figure

外腕ダイニンのクラミドモナス軸糸微小管上への構築に必要な蛋白質間相互作用の研究

学位の種別:課程博士University of Tokyo(東京大学

Protein–protein interactions between intermediate chains and the docking complex of Chlamydomonas flagellar outer arm dynein

AbstractOuter arm dynein (OAD) is bound to specific loci on outer-doublet-microtubules by interactions at two sites: via intermediate chain 1 (IC1) and the outer dynein arm docking complex (ODA-DC). Studies using Chlamydomonas mutants have suggested that the individual sites have rather weak affinities for microtubules, and therefore strong OAD attachment to microtubules is achieved by their cooperation. To test this idea, we examined interactions between IC1, IC2 (another intermediate chain) and ODA-DC using recombinant proteins. Recombinant IC1 and IC2 were found to form a 1:1 complex, and this complex associated with ODA-DC in vitro. Binding of IC1 to mutant axonemes revealed that there are specific binding sites for IC1. From these data, we propose a novel model of OAD-outer doublet association

Scaling of the critical slip distance in granular layers

We investigate the nature of friction in granular layers by means of numerical simulation focusing on the critical slip distance, over which the system relaxes to a new stationary state. Analyzing a transient process in which the sliding velocity is instantaneously changed, we find that the critical slip distance is proportional to the sliding velocity. We thus define the relaxation time, which is independent of the sliding velocity. It is found that the relaxation time is proportional to the layer thickness and inversely proportional to the square root of the pressure. An evolution law for the relaxation process is proposed, which does not contain any length constants describing the surface geometry but the relaxation time of the bulk granular matter. As a result, the critical slip distance is scaled with a typical length scale of a system. It is proportional to the layer thickness in an instantaneous velocity change experiment, whereas it is scaled with the total slip distance in a spring-block system on granular layers.Comment: 4 papge

Adherence to behavior changes for COVID-19 prevention in communitydwelling older adults

Background: Preventing coronavirus disease 2019 (COVID-19) in older people is an important public health issue. The purpose of this study was to investigate the relationship between the level of fear regarding COVID-19 and adherence to COVID-19 prevention measures among community-dwelling older adults.Methods: This study was a cross-sectional survey conducted from July 15 to August 19, 2020, in 127 community-dwelling older adults ≥65 years old in Japan. A questionnaire including participants’ basic attributes (age, sex, body mass index, and family structure), levels of fear regarding COVID-19, increasing adherence to four behaviors (restrictions on going out, maintaining physical distancing, wearing masks, and washing hands) for COVID-19 prevention, and its stress levels was used. We calculated the relationship between the level of fear of COVID-19 and the level of each behavioral change using Spearman’s correlation coefficient (rs).Results: About 95% of older adults displayed fear of COVID-19. Rates of adherence to all four COVID-19 prevention measures increased to approximately 80–95%. However, about 40–55% of older adults were stressed by all behavior modifications except washing hands. The increasing level of fear regarding COVID-19 correlated positively with decreasing frequency of going out (rs=0.280, p=0.001) and increasing frequency of washing hands (rs=0.336, p<0.001).Conclusion: The behavioral changes of COVID-19 prevention measures in community-dwelling older people were excellent with increasing adherence rates. While such high adherence rates may increase the preventive effect in community-dwelling older people, the new lifestyle during the COVID-19 epidemic may cause frailty due to restrictions on going out and stress regarding behavior modifications

Identification of the agg1 mutation responsible for negative phototaxis in a “wild-type” strain of Chlamydomonas reinhardtii

AbstractThe unicellular green alga Chlamydomonas reinhardtii is a model organism for various studies in biology. CC-124 is a laboratory strain widely used as a wild type. However, this strain is known to carry agg1 mutation, which causes cells to swim away from the light source (negative phototaxis), in contrast to the cells of other wild-type strains, which swim toward the light source (positive phototaxis). Here we identified the causative gene of agg1 (AGG1) using AFLP-based gene mapping and whole genome next-generation sequencing. This gene encodes a 36-kDa protein containing a Fibronectin type III domain and a CHORD-Sgt1 (CS) domain. The gene product is localized to the cell body and not to flagella or basal body

Chlamydomonas DYX1C1/PF23 is essential for axonemal assembly and proper morphology of inner dynein arms

Cytoplasmic assembly of ciliary dyneins, a process known as preassembly, requires numerous non-dynein proteins, but the identities and functions of these proteins are not fully elucidated. Here, we show that the classical Chlamydomonas motility mutant pf23 is defective in the Chlamydomonas homolog of DYX1C1. The pf23 mutant has a 494 bp deletion in the DYX1C1 gene and expresses a shorter DYX1C1 protein in the cytoplasm. Structural analyses, using cryo-ET, reveal that pf23 axonemes lack most of the inner dynein arms. Spectral counting confirms that DYX1C1 is essential for the assembly of the majority of ciliary inner dynein arms (IDA) as well as a fraction of the outer dynein arms (ODA). A C-terminal truncation of DYX1C1 shows a reduction in a subset of these ciliary IDAs. Sucrose gradients of cytoplasmic extracts show that preassembled ciliary dyneins are reduced compared to wild-type, which suggests an important role in dynein complex stability. The role of PF23/DYX1C1 remains unknown, but we suggest that DYX1C1 could provide a scaffold for macromolecular assembly

Describing coseismic groundwater level rise using tank model in volcanic aquifers, Kumamoto, southern Japan

The change of groundwater levels after the 2016 Mw 7.0 Kumamoto crustal earthquake was evaluated using a simple conceptual hydrological model in an attempt to show the presence, intensity, and probable mechanism of water level rise observed in Kumamoto where a comprehensive observation-well network exists. A tank model was applied to verify 16 wells in the study field. In the model groundwater levels were first calibrated for the periods in ca. 2 years before the main shock using several hydrological parameters including precipitation, evapotranspiration, water recharge and discharge, and artificial recharge by irrigation. Water levels were then simulated by extrapolating this law of water fluctuating patterns for ca. 2.5 years after the main shock of the earthquake, without considering hydrogeological changes due to the earthquake. A difference in groundwater levels between observation and simulation results yields a degree of coseismic water level rises for each well. The coseismic abnormal water level increase was calculated to be ~11 m in 4?5 month after the main shock and was most significantly on the western slope of the Aso caldera rim mountains. The spatial distribution of the coseismic water increases clarified that the most dominate increasing anomalies prevail at mountain feet surrounding the plains, suggesting the occurrence of coseismic mountain water release resulting in the rise of water levels in downslope aquifers. Identified coseismic water level increases still continue up to 2.5 years after the earthquake, probably because changes in hydrogeological properties in mountain aquifers, i.e., permeability, are still sustained. Our forecasting water recovering trends require ca. 3.5?5 year after the earthquake for complete recovery to the original conditions. We demonstrated that our approaches are capable of describing coseismic water level changes and could potentially be applied to other fields