Magnetotail reconnection asymmetries in an ion-scale, Earth-like magnetosphere

We use a newly developed global Hall magnetohydrodynamic (MHD) code to investigate how reconnection drives magnetotail asymmetries in small, ion-scale magnetospheres. Here, we consider a magnetosphere with a similar aspect ratio to Earth but with the ion inertial length (δi) artificially inflated by a factor of 70: δi is set to the length of the planetary radius. This results in a magnetotail width on the order of 30 δi, slightly smaller than Mercury's tail and much smaller than Earth's with respect to δi. At this small size, we find that the Hall effect has significant impact on the global flow pattern, changing from a symmetric, Dungey-like convection under resistive MHD to an asymmetric pattern similar to that found in previous Hall MHD simulations of Ganymede's subsonic magnetosphere as well as other simulations of Mercury's using multi-fluid or embedded kinetic physics. We demonstrate that the Hall effect is sufficient to induce a dawnward asymmetry in observed dipolarization front locations and find quasi-periodic global-scale dipolarizations under steady, southward solar wind conditions. On average, we find a thinner current sheet dawnward; however, the measured thickness oscillates with the dipolarization cycle. During the flux-pileup stage, the dawnward current sheet can be thicker than the duskward sheet. This could be an explanation for recent observations that suggest Mercury's current sheet is actually thicker on the duskside: a sampling bias due to a longer lasting “thick” state in the sheet.

Effects of L1 Transfer Are Profound, Yet Native-Like Processing Strategy Is Attainable: Evidence From Advanced Learners’ Production of Complex L2 Chinese Structures

English as a verb-medial language has a short-before-long preference, whereas Korean and Japanese as verb-final languages show a long-before-short preference. In second language (L2) research, little is known regarding how L1 processing strategies affect the ultimate attainment of target structures. Existing work has shown that native speakers of Chinese strongly prefer to utter demonstrative-classifier (DCL) phrases first in subject-extracted relatives (DCL-SR-N) and DCLs second in object-extracted relatives (OR-DCL-N). But it remains unknown whether L2 learners with typologically different language backgrounds are able to acquire native-like strategies, and how they deviate from native speakers or even among themselves. Using a phrase-assembly task, we investigated advanced L2-Chinese learners whose L1s were English, Korean, and Japanese, because English lacks individual classifiers and has postnominal relative clause (RC), whereas Korean and Japanese have individual classifiers and prenominal RCs. Results showed that the English and Korean groups deviated from the native controls’ asymmetric pattern, but the Japanese group approximated native-like performance. Furthermore, compared to the English group, the Korean and Japanese groups favored the DCL-second configuration in SRs and ORs. No differences were found between the Korean and Japanese groups. Overall, our findings suggest that L1 processing strategies play an overarching role in L2 acquisition of asymmetric positioning of DCLs in Chinese RCs.

Global and regional shock transmission: an Asian perspective

This paper constructs and uses the global input–output (GIO) table with 35 industries, 29 endogenous countries and 59 exogenous countries, and develops new indices to measure the degree of shock transmission in terms of intermediate goods and value-added embodied in production induced by negative global demand shock to finished goods. After the Global Financial Crisis (GFC) in 2008, China did not experience a large decline in economic growth, even though China’s gross exports fell most severely among Asian countries. In contrast, a sharp decrease in Japanese GDP in 2009 is a consequence of a substantial decline in finished goods exports, especially in the transport equipment industry. In Japan, the shock effect tends to be absorbed in its domestic sector and is not transmitted to other foreign countries. An asymmetric pattern of shock transmission between Japan and other Asian countries can explain why Japan was more affected by GFC than other Asian countries.

Impact of comorbidity on family genetic risk profiles for psychiatric and substance use disorders: a descriptive analysis

Background – Comorbidity between psychiatric disorders is extensive but, from a genetic perspective, still poorly understood. Modern molecular genetic approaches to this problem are limited by a reliance on case–control designs. Methods – In 5 828 760 individuals born in Sweden from 1932–1995 with a mean (s.d.) age at follow-up of 54.4 (18.1), we examined family genetic risk score (FGRS) profiles including internalizing, psychotic, substance use and developmental disorders in 10 pairs of psychiatric and substance use disorders diagnosed from population registries. We examined these profiles in three groups of patients: disorder A only, disorder B only and comorbid cases with both disorders. Results – The most common pattern of findings, seen in five pairings, was simple and quantitative. Comorbid cases had higher FGRS than both non-comorbid cases for all (or nearly all) disorders. However, the pattern was more complex in the remaining five pairings and included qualitative changes where the comorbid cases showed no increases in FGRS for certain disorders and in a few cases significant decreases. Several comparisons showed an asymmetric pattern of findings with increases, in comorbidity compared to single disorder cases, of the FGRS for only one of the two disorders. Conclusions – The examination of FGRS profiles in general population samples where all disorders are assessed in all subjects provides a fruitful line of inquiry to understand the origins of psychiatric comorbidity. Further work will be needed, with an expansion of analytic approaches, to gain deeper insights into the complex mechanisms likely involved.

Partisan Agendas

Contentious politics is nothing new for a partisan Senate where compromise and bipartisan cooperation seem like increasingly outdated conceptions. This chapter explains patterns in partisan communication and explains why conservative senators and party leaders are more likely to adopt a partisan-warrior style of strategic communication on Twitter. When it comes to communicating partisan priorities as part of senators’ rhetorical agendas, the data reveals an asymmetric pattern of partisan rhetoric where Republican senators and party leaders are more likely to prioritize partisan politics, reinforcing their partisan reputation for constituents with a similar ideology. Republicans are more likely to use partisan rhetoric on Twitter, both attacking their Democratic counterparts in Congress or the White House and signaling support for their own party. And they continue to do this over time given data that shows how Republican senators and party leaders since 2013 have consistently communicated as partisan warriors.

The Asymmetric Pattern of Population Mobility during the Spring Festival in the Yangtze River Delta Based on Complex Network Analysis: An Empirical Analysis of “Tencent Migration” Big Data

Population mobility patterns are an important reflection of the future distribution of migrant populations and the evolution trends of urbanization patterns. However, although research based on statistical data can reveal the pattern of population flow, it also shows a time lag. Most of the population flow network research based on location services data has failed to fully discuss the symmetry of directional outflows and inflows in the same place and the two-way symmetrical connections between places. This paper creatively proposes and constructs the concept and analysis framework of population flow asymmetry. We used the Yangtze River Delta (YRD) as a typical case and the results of our analysis reveal the temporal and spatial asymmetry of the population flow using complex network analysis methods based on the Spring Festival (SF) population migration big data. We found that the timing asymmetry manifested in such a way that the closer it was to the festival, the greater the scale and intensity of the population movement. This is a feature of the lack of scale and regional differences within China. The spatial asymmetry was manifested in three aspects, network, node, and link, and the core cities with administrative and economic hierarchical advantages dominated the asymmetric pattern of regional population mobility. In addition, distance and administrative boundaries are factors that cannot be ignored in population movements, and they were implicated in the degree of asymmetry by distance enhancement and administrative boundary blocking. The conclusions of this study can not only provide policy decision-making guidelines for population management and resource allocation in the YRD, but they can also provide a reference value for achieving the goal of regional, high-quality, integrated development. Future research will further the discussion and management of socio-economic attributes in order to develop a more detailed and microscopic understanding of the mechanisms of population mobility patterns.

Global and Regional Shock Transmission ―Application of Global Input-Output Table―

This paper constructs and uses the global input-output (GIO) table with 35 industries, 29 endogenous countries and 59 exogenous countries, and develops new indices to measure the degree of shock transmission in terms of intermediate goods and value-added embodied in production induced by negative global demand shock to finished goods. After the Global Financial Crisis (GFC) in 2008, China did not experience a large decline in economic growth, even though China’s gross exports fell most severely among Asian countries. In contrast, a sharp decrease in Japanese GDP in 2009 is a consequence of a substantial decline in finished goods exports, especially in the transport equipment industry. In Japan, the shock effect tends to be absorbed in its domestic sector and is not transmitted to other foreign countries. An asymmetric pattern of shock transmission between Japan and other Asian countries can explain why Japan was more affected by GFC than other Asian countries.

Magnetotail Reconnection Asymmetries in a Small, Earth-Like Magnetosphere

We use a newly developed global Hall MHD code to investigate how reconnection drives magnetotail asymmetries in small magnetospheres. Here, we consider a scaled-down, Earth-like magnetosphere where the ion inertial length (δi) is artificially inflated to one planetary radius (the real Earth's δi ≈ 1/15–1/20 RE in the magnetotail). This results in a magnetotail width on the order of 30 δi, slightly smaller than Mercury's tail and much smaller than Earth's. At this small size, we find that the Hall effect has significant impact on the global flow pattern, changing from a symmetric, Dungey-like convection under resistive MHD to an asymmetric pattern similar to that found in previous Hall MHD simulations of Ganymede's subsonic magnetosphere as well as other simulations of Mercury's using multi-fluid or embedded kinetic physics. We demonstrate that the Hall effect is sufficient to induce a dawnward asymmetry in observed dipolarization front locations and find quasi-periodic global scale dipolarizations under steady, southward solar wind conditions. On average, we find a thinner current sheet dawnward; however, the measured thickness oscillates with the dipolarization cycle. During the flux-pileup stage, the dawnward current sheet can be thicker than the duskward sheet. This could be an explanation for recent observations that suggest Mercury's current sheet is actually thicker on the duskside: a sampling bias due to a longer-lasting "thick" state in the sheet.

Recognising the dynamic form of fire

Encoding and recognising complex natural sequences provides a challenge for human vision. We found that observers could recognise a previously presented segment of a video of a hearth fire when embedded in a longer sequence. Recognition performance declined when the test video was spatially inverted, but not when it was hue reversed or temporally reversed. Sampled motion degraded forwards/reversed playback discrimination, indicating observers were sensitive to the asymmetric pattern of motion of flames. For brief targets, performance increased with target length. More generally, performance depended on the relative lengths of the target and embedding sequence. Increased errors with embedded sequence length were driven by positive responses to non-target sequences (false alarms) rather than omissions. Taken together these observations favour interpreting performance in terms of an incremental decision-making model based on a sequential statistical analysis in which evidence accrues for one of two alternatives. We also suggest that prediction could provide a means of providing and evaluating evidence in a sequential analysis model.