Reference Frame Research Articles

Distinct codes for environment structure and symmetry in postrhinal and retrosplenial cortices

Complex sensory information arrives in the brain from an animal’s first-person (‘egocentric’) perspective. However, animals can efficiently navigate as if referencing map-like (‘allocentric’) representations. The postrhinal (POR) and retrosplenial (RSC) cortices are thought to mediate between sensory input and internal maps, combining egocentric representations of physical cues with allocentric head direction (HD) information. Here we show that neurons in the POR and RSC of female Long-Evans rats are tuned to distinct but complementary aspects of local space. Egocentric bearing (EB) cells recorded in square and L-shaped environments reveal that RSC cells encode local geometric features, while POR cells encode a more global account of boundary geometry. Additionally, POR HD cells can incorporate egocentric information to fire in two opposite directions with two oppositely placed identical visual landmarks, while only a subset of RSC HD cells possess this property. Entorhinal grid and HD cells exhibit consistently allocentric spatial firing properties. These results reveal significant regional differences in the neural encoding of spatial reference frames.

Research on picosecond synchronization control between synchrotron radiation X-ray pulse and femtosecond laser pulse on SSRF

The laser-pumped X-ray detection method is a crucial tool for investigating molecular dynamics, allowing researchers to study ultrafast structural changes within materials. This method demands extremely high precision in the synchronization and delay timing between the pump pulse and the probe pulse. In this study, we explored picosecond (ps)-level clock synchronization control between synchrotron radiation X-ray pulses and femtosecond (fs) laser pulses at the BL05U (d-Line) of the Shanghai Synchrotron Radiation Facility (SSRF). Utilizing the X-ray pulses generated by the 40 ps/0.3 mA electron beam bunch from the SSRF and femtosecond laser pulses with high repetition rates and high emission power, we conducted synchronization experiments. A custom-developed picosecond time synchronization control system and a high dynamic range X-ray streak camera with picosecond time resolution were used as detectors, enabling ultra-precise time synchronization monitoring of X-ray and laser pulses. This setup achieves higher time resolution without the need for photodiodes and oscilloscopes. Using the X-ray pulses as a stationary reference frame, we adjusted the clock synchronization control system to delay the laser pulses and measured their relative timing changes with the X-ray streak camera. The experiments demonstrated a time resolution better than 10 ps, providing a foundation for achieving 60 ps time resolution in laser-pumped X-ray detection experiments at the SSRF.

Five latent factors underlie response to immunotherapy

Only a subset of patients treated with immune checkpoint inhibitors (CPIs) respond to the treatment, and distinguishing responders from non-responders is a major challenge. Many proposed biomarkers of CPI response and survival probably represent alternative measurements of the same aspects of the tumor, its microenvironment or the host. Thus, we currently ignore how many truly independent biomarkers there are. With an unbiased analysis of genomics, transcriptomics and clinical data of a cohort of patients with metastatic tumors (n = 479), we discovered five orthogonal latent factors: tumor mutation burden, T cell effective infiltration, transforming growth factor-beta activity in the microenvironment, prior treatment and tumor proliferative potential. Their association with CPI response and survival was observed across all tumor types and validated across six independent cohorts (n = 1,491). These five latent factors constitute a frame of reference to organize current and future knowledge on biomarkers of CPI response and survival.

Purchase intention toward E-pharmacy: the consumption value perspective

Purpose This study aims to examine consumer purchase behavior towards E-pharmacy from a consumption value perspective. For this purpose, the influence of consumption values on consumer purchase intention is evaluated. Further, the role of consumer involvement in online purchase setup in the context of E-pharmacy is observed using moderation analysis. Design/methodology/approach The study used a cross-sectional survey design, wherein the respondents in the Delhi-National Capital Region of India were approached using a purposive sampling method. Responses received through the structured questionnaire were subjected to analysis using Smart PLS Version 4.0.9.6. Findings Results indicate a significant influence of functional (partial), emotional, social and conditional values on consumers’ purchase intention. Moreover, the moderation effect of consumer online involvement is seen in functional value (partial) and emotional value–purchase intention relationships. Research limitations/implications This study reinforces the use of the consumption value perspective to explain consumer purchase behavior toward information system (IS)-based platforms such as E-pharmacy. Some of the results, in this context, that did not establish significant relationships between a given form of consumption values and purchase intention, open up the possibilities of retesting the said relationships in the future. The researchers would realize the benefit of such examinations, as the E-pharmacy sector further evolves and matures in the future. Further, the successful establishment of a significant moderating role of consumer online involvement in certain consumption value-purchase intention relationships such as safety, perceived convenience and comfort value paves the way for future researchers to explore consumer online involvement for a similar role in IS research. Practical implications This study provides cues for E-pharmacy marketers to focus on enhancing product safety, usage comfort, users’ social image and awareness toward health consciousness that will help build purchase intention and assist in overcoming the challenges in the long run. It further suggests that marketers should have a strong re-look at forming price value perceptions and they must enhance the interactive features of the company’s mobile apps/websites with the help of the emerging artificial intelligence tools to re-orient the epistemic value and perceived convenience value toward E-pharmacy services. Furthermore, this study recommends following digital marketing practices to increase consumer online involvement, which would help strengthen perceived convenience formation that would otherwise be difficult to attain for E-pharmacy consumers. Originality/value This study provides novel insight into consumer purchase intention evaluation through the consumption value perspective in an emerging E-pharmacy market. The consumption value frame of reference helps to understand consumers’ buying rationale that affects their buying behavior beyond the initial adoption. Further, the moderation analysis of consumer online involvement provides an additional dimension to understanding consumer buying behavior concerning E-pharmacy.

Three-dimensional interseismic crustal deformation in the northeastern margin of the Tibetan Plateau using GNSS and InSAR

The nature of the crustal deformation of the northeastern margin of the Tibetan Plateau is vital for elucidating the expansion mechanism of the plateau. We installed 21 continuous GNSS stations and obtained a horizontal velocity field with high spatial resolution. We also acquired a line-of-sight(LOS)velocity field with Sentinel-1 images covering the study area from 2014 to 2022. A multi-scale spherical wavelet method was employed to unify the reference frames of GNSS and InSAR data. After unifying the reference frame, the two data types achieve high consistency. Combining GNSS and InSAR velocities yielded the three-dimensional interseismic velocity field in the northeastern margin of the Tibetan Plateau. Furthermore, we analyzed the crustal deformation characteristics based on the three-dimensional deformation field. The crustal deformation exhibits a pronounced northeastward shift relative to the Ordos block, whereas the interior of the Ordos block remains remarkably stationary, behaving as a rigid unit. The Liupanshan fault is primarily characterized by uplift, devoid of any notable horizontal deformation across the fault. The left-lateral strike-slip mainly characterizes the Haiyuan fault.. The maximum east–west deformation velocity on the southern side of the fault is approximately 3.9 mm/yr, decreasing to about 1.0 mm/yr at the eastern end of the fault. The western segment of the West Qinling fault exhibits a minor east–west motion. Our result provides essential data for further study of the crustal deformation patterns.

A Transformative Orientation Model for Encouraging Responsible Marketing Actions

This set of studies tackles a timely, important, yet often overlooked component of marketing—encouraging marketing actors to engage in a socially just and responsible orientation to improve decision-making. We build on ethical, sustainable, social justice, and social marketing pedagogy by combining transformative learning theories with stakeholder recognition to provide a model that explains how marketers can develop a transformative orientation. With five studies, including three semester-long field experiments, one natural experiment/event study on Black Lives Matter Google searches, and a lab experiment, we present captivating empirical evidence that market actors can change their orientation to be more responsible and just. The model recognizes the importance of using a balanced frame of reference for marketing, and how this is mediated by metacognition activation and perspective gathering. This paper provides initial empirical evidence demonstrating how the way marketing materials are presented can improve the degree of transformation.

Development of Hybrid SOGI-Resonant Controller in DQ reference frame for decoupled PQ control of a VSI under nonlinear loading

Development of Hybrid SOGI-Resonant Controller in DQ reference frame for decoupled PQ control of a VSI under nonlinear loading

The ambiguous impact of populist trade discourses on the international economic order

Abstract The relationship between populism and free trade has historically been a complex one. This article argues that populism affects trade not by expressing consistent economic preferences, but by operating as a discourse that articulates external policies as a struggle for popular recognition. We analyse trade discourses of Donald Trump and Brexiteers following their victories in the 2016 United States presidential election and the referendum on European Union membership in the United Kingdom. These populist movements expressed opposing trade preferences: Trumpism was identified with protectionism, while Brexiteers supported free trade. However, they both articulated trade as a way to regain popular sovereignty from elites and hostile outsiders. A discursive approach helps identify a common logic in how populists articulate foreign relations despite pursuing nominally opposing policies. While this populist logic pertains primarily to domestic mobilization, it has implications for the international order as well, as evidenced in the persistence of protectionist instincts in the US under President Biden and the acceptance of a ‘global’ trade policy outside the EU as the new frame of reference for UK external economic relations.

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

An Improved Collaborative Control Scheme to Resist Grid Voltage Unbalance for BDFG-Based Wind Turbine

This article presents an improved collaborative control to resist grid voltage unbalance for brushless doubly fed generator (BDFG)-based wind turbine (BDFGWT). The mathematical model of grid-connected BDFG including machine side converter (MSC) and grid side converter (GSC) in the αβ reference frame during unbalanced grid voltage condition is established. On this base, the improved collaborative control between MSC and GSC is presented. Under the control, the control objective of the whole BDFGWT system, including canceling the pulsations of electromagnetic torque and the unbalance of BDFGWT’s total currents, pulsations of BDFGWT’s total powers are capable of being realized; therefore, the control capability of BDFGWT to resist unbalanced grid voltage is greatly improved. Moreover, improved single-loop current controllers adopting PR regulators are proposed for both MSC and GSC where the sequence extractions for both MSC and GSC currents are not needed any more, and hence the proposed control is much simpler. In addition, the transient characteristics are also improved. Moreover, in order to achieve the decoupling control of current and average power, current controller also adopts the feedforward control approach. Case studies for a two MW BDFGWT system are implemented, and the results verify that the presented control is capable of effectively improving the control capability for BDFGWT to resist grid voltage unbalance and exhibit good stable and dynamic control performances.

The Alienation–Insulation Dynamic and the Low-Wage Migrant Work Ethic

Low-wage labour migrants moving from lower- to higher-income countries have been celebrated for their strong work ethic over recent decades. The paper draws on qualitative insights from European horticulture to explore why low-wage migrants work as hard as they do. We centre our analysis on an ‘alienation–insulation’ dynamic. Specifically, we show how migrants are particularly alienated in ways that are different to that of the immobile working class. However, we also argue that migrants’ spatial (their dual frame of reference) and temporal (their liminal) agency insulates them from this alienation to some degree. It is important, in this respect, to differentiate between alienation as ostensibly encountered (an objective phenomenon) and the actual felt experiences of alienation (as a subjective phenomenon). We conclude that the alienation–insulation dynamic is a key, but underexplored, element in understanding the complex relationship between labour mobility and labour power.

Chronotopes of Transnational Literacies: How Youth Live and Imagine Social Worlds in their Digital Media Practices

AbstractThis study explores the transnational literacies that contribute to creating online social connections among migrant youth that may support their development and navigation of life across countries. We examine how social connectedness is semiotically constructed through time–space framing among two youth of Chinese descent who were participants of a larger study of the digital media practices of young people in an urban high school. We build on the concept of chronotope (Bakhtin, 1981) and scholarship of transnational literacies to understand the space–time dimensions of digital literacy practices, specifically how youth create the spatiotemporal context or frame of reference for their actions and positionings with others across geographical distances. Using a case study approach with data from interviews and observations, we analyzed how the youth depicted their transnational social relations within particular time–space frames. Qualitative and discourse analyses of the youths' narrative accounts show that they positioned themselves in proximity with their transnational peers within particular time–space contexts that supported their actions and emotions, and how they made sense of events, issues, practices, and their own identities as transnational individuals. The youths' ideas of schooling and education, and attunement to nationalistic ideologies, were developed through multiple chronotopes in their social connections across countries. This study offers implications for how an attention to the transnational spatiotemporal frame of youths' discourse and narrative may give us a more nuanced understanding of the subjectivity, knowledge, and perspective they derive from their experiences of movement and connection across borders.

Attendance to notable terms promotes narrative frame analysis when students read multiple expository texts

Narrative frames refer to the ways in which information in media is relayed, organized, and contextualized, in order to provide learners with a structure and a frame of reference for new content. Narrative frames are pervasive and have been found to have an effect on individuals’ attitudes and understandings of various social issues. However, students’ abilities to identify and analyze narrative frames during reading have rarely been examined in prior work. In this study, we examine whether two experimental manipulations are able to increase students’ attendance to and analysis of narrative frames when reading four texts addressing a contemporary social issue (i.e., a proposed new housing development). An experimental design was used. Students (N = 141) were randomly assigned to receive a definition of narrative frames, or not, prior to reading and asked to identify notable terms during reading or not. Then, students were asked to read four texts, offering various contrasting perspectives on the construction of a new affordable housing development. Finally, students completed open-ended questions tapping overt and covert narrative frame identification and analysis and multiple text integration. Although providing students with an explicit definition of narrative frames did not improve performance, asking students to attend to notable terms during reading improved overt narrative frame analysis scores. Additionally, students identifying more notable terms during reading was associated with higher overt and covert narrative frame analysis performance. Attending to notable terms during reading may be one means of fostering students’ analysis of overt and covert narrative frames.

A Chimera method for thermal part-scale metal additive manufacturing simulation

This paper presents a Chimera approach for the thermal problems in welding and metallic Additive Manufacturing (AM). In particular, a moving mesh is attached to the moving heat source while a fixed background mesh covers the rest of the computational domain. The thermal field of the moving mesh is solved in the heat source reference frame. The chosen framework to couple the solutions on both meshes is a non-overlapping Domain Decomposition (DD) with Neumann–Dirichlet transmission conditions.Increased steadiness and accuracy within the vicinity of the Heat Affected Zone (HAZ) are the main advantages of this approach. The steadiness gain allows for the use of larger time steps, which is vital in AM applications and, in particular, Laser Powder Bed Fusion (LPBF), where the disparity of time scales represents a major hurdle. Moreover, enhanced accuracy can be observed in the resulting morphology of the melt pool. It will be shown that the method addresses classical shortcomings pointed out by Goldak without requiring the use of an asymmetrical heat source profile.

On the Interpretation of Cosmic Acceleration

In relativity, the Newtonian concepts of velocity and acceleration are observer-dependent quantities that vary with the chosen frame of reference. It is well established that in the comoving frame, cosmic expansion is currently accelerating; however, in the rest frame, this expansion is actually decelerating. In this paper, we explore the implications of this distinction. The traditional measure of cosmic acceleration, denoted by q, is derived from the comoving frame and describes the acceleration of the scale factor a for a 3D space-like homogeneous sphere. We introduce a new parameter qE representing the acceleration experienced between observers within the light cone. By comparing qE to the traditional q using observational data from Type Ia supernovae (SN) and the radial clustering of galaxies and quasars (BAO)—including the latest results from DESI2024—our analysis demonstrates that qE aligns more closely with these data. The core argument of the paper is that Λ—regardless of its origin—creates an event horizon that divides the manifold into two causally disconnected regions analogous to conditions inside a black hole’s interior, thereby allowing for a rest-frame perspective qE in which cosmic expansion appears to be decelerating and the horizon acts like a friction term. Such a horizon suggests that the universe cannot maintain homogeneity outside. The observed cosmological constant Λ can then be interpreted not as a driver of new dark energy or a modification of gravity but as a boundary term exerting an attractive force, akin to a rubber band, resisting further expansion and preventing event horizon crossings. This interpretation calls for a reconsideration of current cosmological models and the assumptions underlying them.

Optimal design of hybrid green energy powered reduced switch converter based shunt active power filter using horse herd algorithm

Renewable energy sources are playing a leading role in today's world. However, integrating these sources into the distribution network through power electronic devices can lead to power quality (PQ) challenges. This work addresses PQ issues by utilizing a shunt active power filter in combination with an Energy Storage System (ESS), a Wind Energy Generation System (WEGS), and a Solar Energy System. While most previous research has relied on complex methods like the synchronous reference frame (SRF) and active-reactive power (pq) approaches, this work proposes a simplified approach by using a neural network (NN) for generating reference signals, along with the design of a five-level reduced switch voltage source converter. The gain values of the proportional-integral controller (PIC), as well as the parameters for the shunt filter, boost, and buck-boost converters in the WEGS and ESS, are optimally selected using the horse herd optimization algorithm. Additionally, the weights and biases for the neural network (NN) are also determined using this method. The proposed system aims to achieve three key objectives: (1) stabilizing the voltage across the DC bus capacitor; (2) reducing total harmonic distortion (THD) and improving the power factor; and (3) ensuring superior performance under varying demand and PV irradiation conditions. The system's effectiveness is evaluated through three different testing scenarios, with results compared against those obtained using the genetic algorithm, biogeography-based optimization (BBO), as well as conventional SRF and pq methods with PIC. The results clearly demonstrate that the proposed method achieves THD values of 3.69%, 3.76%, and 4.0%, which are lower than those of the other techniques and well within IEEE standards. The method was developed using MATLAB/Simulink version 2022b.

Modeling Polymer Microencapsulation Processes Using CFD and Population Balance Models

Computational fluid dynamics (CFD) modeling has emerged as a valuable tool for investigating complex processes like microencapsulation. This paper aims to validate the ability of CFD simulations to predict particle size distribution in a polymer microencapsulation process. The CFD modeling approach employed a Eulerian multiphase framework, incorporating a discrete population balance model to track the evolution of the droplet population. A realizable k-ε turbulence model and a multiple reference frame strategy were utilized to capture the system’s flow dynamics. The results reveal that while the CFD simulations align well with experimental data at higher agitation speeds (>10,000 rpm), discrepancies arise at lower speeds (<7500 rpm), indicating a challenge in accurately capturing turbulent viscous regimes. Despite these challenges, the CFD model demonstrates robust predictive capabilities for droplet formation and distribution in microencapsulation processes, validated by error margins within the acceptable limits. The validated model can be used as a reliable tool to guide experimental efforts and optimize process parameters, contributing to an enhanced understanding and control of microencapsulation processes.

Unpacking conflict-ridden everyday life: Perspectives from life-environmentalism

This paper examines the concept of life-environmentalism ( seikatsu kankyō shugi), which emerged in the 1980s as a shared research framework among Japanese social scientists studying the adverse effects of modern industrialization of everyday life in rural communities. Despite its recognition in Japan, the life-environmentalist approach remains largely unknown to Anglophone literature. While the recently published book, Everyday Life-Environmentalism, provides an introductory English-language text, it lacks thorough theoretical articulation of the approach in relation to contemporary Anglophone approaches. This paper centers on actor-network theory, a widely circulated approach within post-human and more-than-human geographies, as a comparative frame of reference to elucidate key characteristics of life-environmentalism. Through a comparative examination of the applications of these approaches to a local case study, we suggest that life-environmentalism offers valuable insights when analyzing socioenvironmental controversies and community-level responses, particularly in contexts where a long-standing social community is central to the analysis.

Mass and Thermodiffusion in Non-equilibrium Fluctuating Hydrodynamics

Mass and thermodiffusion are transport phenomena in fluid mixtures important in many applications. In this paper it is argued that these transport phenomena have even become more interesting in view of some surprising discoveries from fluctuating hydrodynamics leading to possible new emerging issues in non-equilibrium thermodynamics. A short review of the history of this subject is presented. The paper then addresses the problem that the conventional mass and thermodiffusion coefficients depend on the frame of reference. A simple solution to this problem is elucidated.

Two‐Spacecraft Observations of Asymmetric Martian Bow Shock: Conjunctions of Tianwen‐1 and MAVEN

AbstractThe Martian bow shock has been extensively studied through magnetic field and plasma instrument observations from various Mars space missions. However, prior investigations primarily involve statistical analyses based on single spacecraft crossings, leaving the asymmetry of the Martian bow shock unstudied through simultaneous two‐spacecraft observations. In this study, utilizing simultaneous observations from Tianwen‐1 and MAVEN, we examine the instantaneous asymmetry of the Martian bow shock. We present the asymmetry of the Martian bow shock in the Mars‐Solar‐Electric and Mars‐Solar‐Orbital reference frames, possibly influenced by the solar wind motional electric field and Martian crustal magnetic field, respectively. Moreover, we suggest that the bow shock exhibits increased asymmetry under stronger solar wind motional electric field conditions. This study highlights how a two‐point observation approach offers valuable insights into the dynamic behavior of the Martian induced magnetosphere.