Regulated Phase Separation in Al-Ti-Cu-Co Alloys through Spark Plasma Sintering Process.

With the goal of developing lightweight Al-Ti-containing multicomponent alloys with excellent mechanical strength, an Al-Ti-Cu-Co alloy with a phase-separated microstructure was prepared. The granulometry of metal particles was reduced using planetary ball milling. The particle size of the metal powders decreased as the ball milling time increased from 5, 7, to 15 h (i.e., 6.6 ± 6.4, 5.1 ± 4.3, and 3.2 ± 2.1 µm, respectively). The reduction in particle size and the dispersion of metal powders promoted enhanced diffusion during the spark plasma sintering process. This led to the micro-phase separation of the (Cu, Co)2AlTi (L21) phase, and the formation of a Cu-rich phase with embedded nanoscale Ti-rich (B2) precipitates. The Al-Ti-Cu-Co alloys prepared using powder metallurgy through the spark plasma sintering exhibited different hardnesses of 684, 710, and 791 HV, respectively, while maintaining a relatively low density of 5.8-5.9 g/cm3 (<6 g/cm3). The mechanical properties were improved due to a decrease in particle size achieved through increased ball milling time, leading to a finer grain size. The L21 phase, consisting of (Cu, Co)2AlTi, is the site of basic hardness performance, and the Cu-rich phase is the mechanical buffer layer between the L21 and B2 phases. The finer network structure of the Cu-rich phase also suppresses brittle fracture.

Reducing single-use cutlery with green nudges: Evidence from China's food-delivery industry.

Rising consumer demand for online food delivery has increased the consumption of disposable cutlery, leading to plastic pollution worldwide. In this work, we investigate the impact of green nudges on single-use cutlery consumption in China. In collaboration with Alibaba's food-delivery platform, Eleme (which is similar to Uber Eats and DoorDash), we analyzed detailed customer-level data and found that the green nudges-changing the default to "no cutlery" and rewarding consumers with "green points"-increased the share of no-cutlery orders by 648%. The environmental benefits are sizable: If green nudges were applied to all of China, more than 21.75 billion sets of single-use cutlery could be saved annually, equivalent to preventing the generation of 3.26 million metric tons of plastic waste and saving 5.44 million trees.

A novel force transduction pathway from a tension sensor to the gate in the mechano-gating of MscL channel.

The bacterial mechanosensitive channel of large conductance MscL is activated exclusively by increased tension in the membrane bilayer. Despite many proposed models for MscL opening, its precise mechano-gating mechanism, particularly how the received force at the tension sensor transmits to the gate remains incomplete. Previous studies have shown that along with amphipathic N-terminus located near the cytoplasmic surface of the membrane, Phe78 residue near the outer surface also acts as a "tension sensor," while Gly22 is a central constituent of the "hydrophobic gate." Present study focused on elucidating the force transmission mechanism from the sensor Phe78 in the outer transmembrane helix (TM2) to the gate in the inner transmembrane helix (TM1) of MscL by applying the patch clamp and molecular dynamics (MD) simulations to the wild type MscL channel and its single mutants at the sensor (F78N), the gate (G22N) and their combination (G22N/F78N) double mutant. F78N MscL resulted in a severe loss-of-function, while G22N MscL caused a gain-of-function channel exhibiting spontaneous openings at the resting membrane tension. We initially speculated that the spontaneous opening in G22N mutant might occur without tension acting on Phe78 residue. To test this hypothesis, we examined the (G22N/F78N) double mutant, which unexpectedly exhibited neither spontaneous activity nor activity by a relatively high membrane tension. To understand the underlying mechanism, we conducted MD simulations and analyzed the force transduction pathway. Results showed that the mutation at the tension sensor (F78N) in TM2 caused decreased interaction of this residue not only with lipids, but also with a group of amino acids (Ile32-Leu36-Ile40) in the neighboring TM1 helix, which resulted in an inefficient force transmission to the gate-constituting amino acids on TM1. This change also induced a slight tilting of TM1 towards the membrane plane and decreased the size of the channel pore at the gate, which seems to be the major mechanism for the inhibition of spontaneous opening of the double mutant channel. More importantly, the newly identified interaction between the TM2 (Phe78) and adjacent TM1 (Ile32-Leu36-Ile40) helices seems to be an essential force transmitting mechanism for the stretch-dependent activation of MscL given that substitution of any one of these four amino acids with Asn resulted in severe loss-of-function MscL as reported in our previous work.

Association between housing damage, present bias and delayed-onset post-traumatic stress symptoms among older adults 9 years after a natural disaster.

BACKGROUND: Previous studies suggest that experience of natural disasters may heighten present bias. Research also suggests that impaired self-control (in particular, heightened present bias) could be linked to delayed-onset post-traumatic stress symptoms (PTSS) among survivors of natural disasters. We examined a hypothesis that the association between disaster experiences and delayed-onset PTSS is mediated through present bias among older survivors of the 2011 Japan earthquake and tsunami. METHODS: The baseline survey was conducted for older adults who lived in a city located 80 km west of the epicentre 7 months before the disaster. Approximately 2.5 and 8.5 years after the disaster, we surveyed older survivors to assess the trajectory of PTSS (2230 participants). We implemented analyses by three analytical groups: (1) resilient versus delayed-onset, (2) resilient versus improved and (3) resilient versus persistent. RESULTS: Logistic regression models showed that major housing damage was linked to raised present bias in all analytical groups (OR 2.47, 95% CI 1.04 to 5.87; OR 2.75, 95% CI 1.20 to 6.29; OR 2.65, 95% CI 1.15 to 6.10, respectively). The present bias, however, was significantly associated with only delayed-onset PTSS (OR 2.05, 95% CI 1.14 to 3.69). In the group of resilient versus delayed onset, housing destruction was also associated with delayed-onset PTSS (OR 2.44, 95% CI 1.11 to 5.37), and the association was attenuated by present bias (OR 2.36, 95% CI 1.07 to 5.18). CONCLUSIONS: Present bias could mediate the association between housing damage and delayed-onset PTSS among older survivors of a natural disaster.

Building social capital with elders' leadership through a community hub "Ibasho" in the Philippines and Nepal.

We quantitatively study the Ibasho project-a unique, innovative community-based project that involves co-creating a building as a social hub. Ibasho's decision-making undertakes a bottom-up approach, differentiating itself from the conventional top-down decision-making process. Using sui generis data, we find that Ibasho projects in the Philippines and Nepal contributed to enhancing social capital among elders in both cases. Yet there are differences between the two communities. In the Philippines, participation in Ibasho increased the number of a participant's friends, or "strong ties," indicating that it is on the intensive margin of human relationships. In contrast, joining Nepal's Ibasho broadened weak ties rather than strong ones. This contrast may stem from the difference in pre-existing social and built infrastructures in the two communities, which were strengthened through the building-human interactions.

Heterogenous effects of the Great East Japan earthquake on prosociality of people depending on their age.

This study investigates the instability of prosociality in the real world by looking at the age-specific non-linear relationship between disaster exposure and prosocial behavior. We employed unique microdata from two communities in Japan that were hit by the Great East Japan Earthquake and Tsunami disaster in 2011. Exploiting exogenous variations in disaster exposure, we find age-specific heterogeneous effects of disaster exposure on prosocial behavior captured by the behavior of sending New Year's cards as well as attitudinal survey questions. Among the older groups, disaster damages undermine prosociality, whereas the younger groups show reinforced prosocial behaviors. These findings can be explained consistently by combining two possible determinants of prosocial behavior: pure or impure altruism and self-enforcements in repeated interactions at workplaces. Age information can help disentangle these two elements at least partially.

Social capital building interventions and self-reported post-disaster recovery in Ofunato, Japan.

Evidence shows that communal resources, cohesion, and social infrastructure can mitigate shocks and enhance resilience. However, we know less about how specific social capital building interventions facilitate recovery in post-disaster environments. Using a survey of over 1000 residents of Ofunato, Japan after the 2011 Tohoku earthquake and tsunami, this study demonstrates that the individuals who actively participated in a community center-created for and led by neighborhood elders-reported higher levels of family and neighborhood recovery than similar individuals who did not participate. Results from ordinal logistic regression analyses, propensity score matching (PSM) and coarsened exact matching (CEM) show arguably stronger causal links between bottom-up, microlocal programs to boost connections in post-disaster areas and post-disaster outcomes. Community-based programs that strengthen social ties even among elderly residents can measurably improve their recoveries.

Gender, entrepreneurship, and coping with the COVID-19 pandemic: The case of GoFood merchants in Indonesia.

This paper examines business performance and crisis-mitigation strategies among micro, small, and medium-sized enterprises (MSMEs) in Indonesia during the COVID-19 pandemic. We utilise a new primary dataset based on administrative records, survey data, and follow-up interviews with merchants using the digital application GoFood, an on-demand cooked food delivery service. Three empirical findings emerge: first, the overall employment size of women-owned businesses shrank more than men-owned businesses after the onset of the pandemic; second, women were more likely than men to cut personal expenditures and use government assistance as crisis-mitigation strategies; and third, competition increased sharply as new merchants entered the platform, with the service areas of both incumbents and entrants shrinking over time. These results have implications for policies on women's entrepreneurship, the uptake of business development services, and financing programs for MSMEs.

Delay discounting in children exposed to disaster.

Delay discounting is an important predictor of future health and academic success in children but can change in environmental uncertainty situations. Here we show that the experience of loss of housing in the Great East Japan Earthquake 2011-but not other psychological trauma such as loss of loved ones-was correlated delay discounting of children. In 2014, we assessed delay discounting in children (N = 167; mean age = 8.3 years-old), who were preschool age at the time of the earthquake (mean age at the time of disaster = 4.8 years-old) in a time-investment exercise where children allocated five tokens between rewards "now" (one candy per token on the same day) versus "one month later" (two candies per token one month later). The number of tokens allocated for "now" was higher by 0.535 (95% confidence interval: -0.012, 1.081) in children who had their housing destroyed or flooded than those with no housing damage. Other types of traumatic experiences were not associated with delay discounting.

Biophysical Mechanisms of Membrane-Thickness-Dependent MscL Gating: An All-Atom Molecular Dynamics Study.

The bacterial mechanosensitive channel, MscL, is activated by membrane tension, acting as a safety valve to prevent cell lysis against hypotonic challenge. It has been established that its activation threshold decreases with membrane thickness, while the underlying mechanism remains to be solved. We performed all-atom molecular dynamics (MD) simulations for the initial opening process of MscL embedded in four different types of lipid bilayers with different thicknesses: 1,2-dilauroyl- sn-glycero-3-phosphocholine (DLPC)), 1,2-dimyristoyl-glycero-3-phosphorylcholine (DMPC), 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC), and 1,2-distearoyl- sn-glycero-3-phosphocholine (DSPC). In response to membrane stretching, channel opening occurred only in the thinner membranes (DLPC and DMPC) in a thickness-dependent way. We found that the MscL opening was governed by the rate and degree of membrane thinning and that the channel opening was tightly associated with the tilting of transmembrane (TM) helices of MscL toward the membrane plane. Upon membrane stretching, the order parameter of acyl chains of thinner membranes (DLPC and DMPC) became smaller, whereas other thicker membranes (DPPC and DSPC) showed interdigitation with little changes in the order parameter. The decreased order parameter contributed much more to membrane thinning than did interdigitation. We conclude that the membrane-thickness-dependent MscL opening mainly arises from structural changes in MscL to match the altered membrane thickness by stretching.

Corynebacterium glutamicum mechanosensitive channels: towards unpuzzling "glutamate efflux" for amino acid production.

Corynebacterium glutamicum has been utilized for industrial amino acid production, especially for monosodium glutamate (MSG), the food-additive for the "UMAMI" category of taste sensation, which is one of the five human basic tastes. Glutamate export from these cells is facilitated by the opening of mechanosensitive channels in the cell membrane within the bacterial cell envelope following specific treatments, such as biotin limitation, addition of Tween 40 or penicillin. A long-unsolved puzzle still remains how and why C. glutamicum mechanosensitive channels are activated by these treatments to export glutamate. Unlike mechanosensitive channels in other bacteria, these channels are not simply osmotic safety valves that prevent these bacteria from bursting upon a hypo-osmotic shock. They also function as metabolic valves to continuously release glutamate as components of a pump-and-leak mechanism regulating the cellular turgor pressure. Recent studies have demonstrated that the opening of the mechanosensitive channel, MscCG, mainly facilitates the efflux of glutamate and not of other amino acids and that the "force-from-lipids" gating mechanism of channels also applies to the MscCG channel. The bacterial types of mechanosensitive channels are found in cell-walled organisms from bacteria to land plants, where their physiological functions have been specialized beyond their basic function in bacterial osmoregulation. In the case of the C. glutamicum MscCG channels, they have evolved to function as specialized glutamate exporters.

Outline of guidelines for the management of vasculitis and vascular disorders in Japan, 2016 revised edition.

The proposal by the 1994 International Chapel Hill Consensus Conference on the Nomenclature of Systemic Vasculitides (CHCC1994) and by the CHCC2012 markedly influenced the classification and way of considering cutaneous vasculitis. In the proposal by the CHCC1994, hypersensitivity angiitis was defined as an equivalent pathological condition to microscopic polyangiitis or cutaneous leukocytoclastic angiitis (CLA), and it was not adopted as a disease name. However, CLA which was positioned as a type of small-vessel vasculitis is only a pathological name. In the proposal by the CHCC2012, a new category of single-organ vasculitis included CLA and cutaneous arteritis. Vasculitis allergica cutis (Ruiter) corresponded to CLA and cutaneous polyarteritis nodosa corresponded to cutaneous arteritis. The Japanese Dermatological Association (JDA) prepared guidelines for the management of vasculitis and vascular disorders in 2008 based on the proposal by the CHCC1994 and their original viewpoint of dermatology. The JDA subsequently revised the 2008 edition guidelines in 2016 following publication of the proposal of the CHCC2012 in Japanese. We presented the outline of the 2016 edition guidelines and propose a treatment algorithm for primary vasculitides based on the evaluation of the cutaneous symptoms for cases suspected as primary cutaneous vasculitides, which integrates the 2008 JDA guideline and CHCC2012 classification. This is the secondary English version of the original Japanese manuscript for the guideline for management of vasculitis and vascular disorders published in the Japanese Journal of Dermatology 127(3); 299-415, 2017.

Residential relocation and change in social capital: A natural experiment from the 2011 Great East Japan Earthquake and Tsunami.

Social connections in the community ("social capital") represent an important source of resilience in the aftermath of major disasters. However, little is known about how residential relocation due to housing destruction affects survivors' social capital. We examined changes in social capital among survivors of the 2011 Great East Japan Earthquake and Tsunami. People who lost their homes were resettled to new locations by two primary means: (i) group relocation to public temporary trailer housing or (ii) individual relocation, in which victims moved into government-provided housing by lottery or arranged for their own accommodation (market rental housing or private purchase/new construction). The baseline for our natural experiment was established 7 months before the 11 March 2011 disaster, when we conducted a survey of older community-dwelling adults who lived 80-km west of the earthquake epicenter. Approximately 2.5 years after the disaster, the follow-up survey gathered information about personal experiences of disaster as well as health status and social capital. Among 3421 people in our study, 79 people moved via group relocation to public temporary trailer housing, whereas 96 people moved on their own. The individual fixed-effects model showed that group relocation was associated with improved informal socializing and social participation (ß coefficient = 0.053, 95% confidence interval: 0.011 to 0.095). In contrast, individual relocation was associated with declining informal socializing and social participation (ß coefficient = -0.039, 95% confidence interval: -0.074 to -0.003). Group relocation, as compared to individual relocation, appeared to preserve social participation and informal socializing in the community.

Tweeting celebrity suicides: Users' reaction to prominent suicide deaths on Twitter and subsequent increases in actual suicides.

A substantial amount of evidence indicates that news coverage of suicide deaths by celebrities is followed by an increase in suicide rates, suggesting a copycat behavior. However, the underlying process by which celebrity status and media coverage leads to increases in subsequent suicides is still unclear. This study collected over 1 million individual messages ("tweets") posted on Twitter that were related to 26 prominent figures in Japan who died by suicide between 2010 and 2014 and investigated whether media reports on suicide deaths that generated a greater level of reactions by the public are likely to be followed by a larger increase in actual suicides. We also compared the number of Twitter posts and the number of media reports in newspaper and on television to understand whether the number of messages on Twitter in response to the deaths corresponds to the amount of coverage in the traditional media. Using daily data from Japan's national death registry between 2010 and 2014, our analysis found an increase in actual suicides only when suicide deaths generated a large reaction from Twitter users. In contrast, no discernible increase in suicide counts was observed when the analysis included suicide deaths to which Twitter users did not show much interest, even when these deaths were covered considerably by the traditional media. This study also found suicides by relatively young entertainers generated a large number of posts on Twitter. This sharply contrasts with the relatively smaller volume of reaction to them generated by traditional forms of media, which focuses more on the deaths of non-entertainers. The results of this study strongly suggest that it is not sufficient to examine only traditional news media when investigating the impact of media reports on actual suicides.

The effectiveness of platform screen doors for the prevention of subway suicides in South Korea.

BACKGROUND: Subway suicide can significantly impact the general public. Platform Screen Doors (PSDs) are considered to be an effective strategy to prevent suicides at subway stations, but the evidence on their effectiveness is limited. METHODS: We assessed the effectiveness of installing half- and full-height platform screen doors in reducing subway suicides using Poisson regression analysis. Ten-year monthly panel data for 121 subway stations between 2003 and 2012 in the Seoul metropolitan area were used for the analysis. RESULTS: We found that installing PSDs decreases fatal suicide cases by 89% (95% CI: 57-97%). We also found that the installation of full-height PSDs resulted in the elimination of subway suicides by completely blocking access to the track area; however, half-height PSDs, which do not extend to the ceiling of the platform, were not as effective as full-height ones. LIMITATION: Our findings were based on the data from a single subway operator for a limited period of time. Accordingly, we did not consider the possibility that some passengers choose to die at a station run by other operators. Our study did not examine the potential substitution effects of other suicide methods. CONCLUSION: Installing physical barriers at subway stations can be an effective strategy to reduce the number of subway suicides; however, half-height PSDs are not as effective as full-height ones, even when they are as high as the height of an adult. Thus, these barriers should be made high enough so that nobody can climb over them.

The Long-Run Socio-Economic Consequences of a Large Disaster: The 1995 Earthquake in Kobe.

We quantify the 'permanent' socio-economic impacts of the Great Hanshin-Awaji (Kobe) earthquake in 1995 by employing a large-scale panel dataset of 1,719 cities, towns, and wards from Japan over three decades. In order to estimate the counterfactual--i.e., the Kobe economy without the earthquake--we use the synthetic control method. Three important empirical patterns emerge: First, the population size and especially the average income level in Kobe have been lower than the counterfactual level without the earthquake for over fifteen years, indicating a permanent negative effect of the earthquake. Such a negative impact can be found especially in the central areas which are closer to the epicenter. Second, the surrounding areas experienced some positive permanent impacts in spite of short-run negative effects of the earthquake. Much of this is associated with movement of people to East Kobe, and consequent movement of jobs to the metropolitan center of Osaka, that is located immediately to the East of Kobe. Third, the furthest areas in the vicinity of Kobe seem to have been insulated from the large direct and indirect impacts of the earthquake.

Molecular dynamics study on protein-water interplay in the mechanogating of the bacterial mechanosensitive channel MscL.

One of the goals of mechanosensitive channel (MSC) studies is to understand the underlying molecular and biophysical mechanisms of the mechano-gating process from force sensing to gate opening. We focus on the latter process and investigate the role of water in the bacterial MSC MscL, which is activated by membrane tension. We analyze the interplay between water and the gate-constituting amino acids, Leu19-Gly26, through molecular dynamics simulations. To highlight the role of water, specifically hydration of the gate, in MscL gating, we restrain lateral movements of the water molecules along the water-vapor interfaces at the top and bottom of the vapor bubble, plugging the closed gate. The gating behaviors in this model and the normal MscL model, in which water movements are unrestrained, are compared. In the normal model, increased membrane tension breaks the hydrogen bond between Leu19 and Val 23 of the inner helix, exposing the backbone carbonyl oxygen of Leu19 to the water-accessible lumen side of the gate. Associated with this activity, water comes to access the vapor region and stably interacts with the carbonyl oxygen to induce a dewetting to wetting transition that facilitates gate expansion toward channel opening. By contrast, in the water-restrained model, carbonyl oxygen is also exposed, but no further conformational changes occur at the gate. This suggests that gate opening relies on a conformational change initiated by wetting. The penetrated water weakens the hydrophobic interaction between neighboring transmembrane inner helices called the "hydrophobic lock" by wedging into the space between their interacting portions.