bluuebunny/crossref_metadata_2025 huggingface dataset:
Conventional breeding of Pacific Island staple crops: A paradox
Authors: Lebot Vincent , Komolong Birte , Labouisse Jean-Pierre , Lawac Floriane , Kaoh Juliane , Waqainabete Logotonu Meleisea , Sukal Amit , Jackson Grahame
Published: June 2023

The Pacific Islands (Melanesia, Micronesia, Polynesia) were the last region in the world to be colonized by modern humans. In their migrations, they dispersed asexually propagated food plants that were first domesticated in Melanesia and exposed them to further selection in diverse insular environments. Later, staple food crops were introduced from South America. In our search for research on genetic resources characterization and breeding conducted between 1950 and 2022, we retrieved 338 references on 13 crop species. All studies were examined, and a review is presented here. Relatively few were on genetic improvement (92 references) compared to those on morphological diversity (246 references). The paradox is that the Pacific is considered a region exposed to the climatic crisis, perhaps more vulnerable than any other region in the world. This paradox is surprising when we consider that most people in the Pacific are growing staple food crops, for household use and/or for local markets, and occasionally for export. In some countries, it involves more than 75% of the population with a considerable contribution to gross domestic product (GDP). Plant breeding has not been considered a priority to mitigate against forthcoming changes in climate, which is likely to be detrimental to crops with a narrow genetic base. We suggest several possible reasons and that conventional plant breeding should be given high priority based on new approaches that include geographical distribution of allelic diversity.
Inverse problems for constrained parabolic variational-hemivariational inequalities
*
Authors: Migórski Stanisław , Cai Dong-ling , Xiao Yi-bin
Published: June 2023

In this paper we study a novel class of inverse problems for parabolic variational–hemivariational inequalities with a unilateral constraint. A theorem on the well-posedness for weak solution is established. Based on a new continuous dependence result, we prove the nonemptiness and stability of the set of optimal solutions to the corresponding inverse problems. We illustrate the results by a quasistatic nonsmooth frictional viscoelastic contact problem with a unilateral constraint for which we derive results on the unique weak solvability, and existence and stability of solutions to the associated inverse problems.
Temperature effects on electric charge transport processes and electron emission in PBS–clay nanocomposites submitted to electron bombardment
Authors: Taktak Sirine , Fakhfakh Slim , Rondot Sébastien , Tara Ahmed , Jbara Omar
Published: June 2023

The effects of isothermal conditions on the charge transport processes and electron emission properties of polybutylene succinate (PBS) nanocomposites with different nanoclay content are investigated. The temperature range used (20 °C–80 °C) is close to the working conditions of materials used in many applications (insulation, sensors). These effects are highlighted using an appropriate device placed in a scanning electron microscope, allowing measurement of induced current in an electron-irradiated specimen. The experimental results show that the rise in temperature involves a decrease in the charging ability and an increase in the conductivity of PBS nanocomposites. The mobility of charge carriers and its thermal dependency deduced during the discharge step were found to be lower for the nanocomposites. A qualitative analysis, expressed to understand these observations, is based on the determination of the electron trap energy distribution (i.e. density of occupied states). Secondary electron emission yield decreased with increasing temperature. The results help us envision a new class of insulators with improved electrical performance. The operating thermal stress, combined with the absence of trapped charges, allows a reduction of electrical and thermal aging and consequently ensures the long-term reliability of the insulators (for instance under High Voltage).
First principles study on magnetic anisotropy of 5d transition metal doped graphdiyne
Authors: Gao Peiyan , Zhong Yi , Xu Lanqing , Zheng Yongping , Huang Zhigao
Published: June 2023

The exceptional porous architecture of graphdiyne (GDY) renders it a potential candidate for magnetic storage media. This paper delves into the magnetic properties of GDY doped with 5d transition metal (TM) atoms via first-principles calculations. Our results divulge the stable embedding of these TM atoms within the triangular cavities of GDY, yielding a significant magneto-crystal anisotropy energy. In particular, Ta@GDY exhibits a remarkable magneto-crystal anisotropy energy value of 11.72 meV. By introducing TM atoms at the top, one could significantly change the magneto-crystal anisotropy energy value of the system, subsequently flipping the easy magnetization axis. The MAE values of Os-

W

3

@GDY and Re-

I
r

3

@GDY are −21.60 meV and −41.68 meV, which are expanded by a factor of 4 and 6 compared to those before the introduction of the top atom. Furthermore, we observed that the magneto-crystal anisotropy energy value of Ta@GDY is modulated by strain. Our research uncovers GDY as a promising substrate for two-dimensional magnetic materials that could be exploited in forthcoming magnetic memory devices.
A hybrid interferometer sensor for simultaneous measurement of temperature and gas pressure based on tapered seven-core fiber and PDMS
Authors: Huang Huiling , Jiang Chao , Hu Chuanju , Deng Longfeng , Li Li , Gao Jiawei , Shu Yukun
Published: June 2023

A novel hybrid interferometer sensor composed of a tapered seven-core fiber (TSCF) and a polydimethylsiloxane (PDMS) cap at the end face of a TSCF is proposed for simultaneous measurement of temperature and gas pressure. TSCF forms a Michelson interferometer (MI), and the PDMS cap on the end surface of TSCF forms a Fabry–Pérot interferometer (FPI). The sensing head consisted of a cascade of MI and FPI. When the external temperature or gas pressure changes, owing to the thermal effect or elastic deformation of PDMS, the interference spectrum of the FPI shifts significantly, so the FPI is very sensitive to temperature and gas pressure. MI, which is made of quartz optical fiber, is sensitive only to temperature and is not to gas pressure. The experimental results show that FPI has a temperature sensitivity of −0.22 nm °C−1 in the temperature range of 40 °C–80 °C, and a gas pressure sensitivity of −2.27 nm MPa−1 in the gas pressure range of 0–0.3 MPa. MI has a temperature sensitivity of 0.05 nm °C−1 in the temperature range of 40 °C–80 °C, and a gas pressure sensitivity of zero in the gas pressure range of 0–0.3 MPa. Using the temperature and gas pressure sensitivities of FPI and MI to construct a measurement matrix, it is possible to simultaneously measure temperature and gas pressure, eliminating their cross-sensitivity. This sensor has the comprehensive advantages of compact structure, small size, easy manufacturing, low cost, high reliability, and high sensitivity, and is expected to be applied in industrial practice.
Automatic exposure control method for 3D shape measurement of specular surface based on digital fringe projection
Authors: Feng Luyuan , Kang Jiehu , Li Hongtong , Zhang Zhen , Sun Zefeng , Wu Bin
Published: June 2023

Digital fringe projection (DFP) is widely applied in three-dimensional (3D) shape measurements. However, its performance is severely disturbed while measuring complex surfaces with an extensive range of reflectivity. In this paper, to enhance the underexposed regions and reduce the saturated regions, an automatic and effective method is proposed for the multi-exposure determination of the DFP system. During the whole process, only one unsaturated image must be captured preliminarily, which could establish an adaptive strategy based on the intensity value distribution function. Raw absolute phase maps captured with different exposure times are synthesized at the pixel level for phase retrieval and 3D reconstruction. To evaluate the effectiveness of our method, a high dynamic range method and a global optimal exposure method are introduced for comparison. Verification experiments demonstrate that our method performs better for the 3D reconstruction results of complex surfaces with a large reflectivity range.
Variational properties of nonlocal singular problems
Authors: Canino Annamaria , Montoro Luigi , Sciunzi Berardino , Trombetta Alessandro
Published: June 2023

We consider a general class of nonlocal problems involving the fractional Laplacian and singular nonlinearities and we deal with the variational characterization of the solutions. Even though solutions generally have not fractional Sobolev regularity, we provide a variational characterization of the solutions via a suitable action functional.
A virtual-pinhole PET device for improving contrast recovery and enhancing lesion detectability of a one-meter-long PET scanner: a simulation study
Authors: Jiang Jianyong , Hua Jianlang , Wang Haihao , Yuan Ziquan , Meng Yuan , Lu Haoyu , Liu Steven , Chen Yunlai , Tai Yuan-Chuan
Published: June 2023

This paper presents a simulation study to demonstrate that the contrast recovery coefficients (CRC) and detectability of small lesions of a one-meter-long positron emission tomography (PET) scanner can be further enhanced by the integration of high resolution virtual-pinhole (VP) PET devices. The scanner under investigation is a Siemens Biograph Vision Quadra which has an axial field-of-view (FOV) of 106 cm. The VP-PET devices contain two high-resolution flat panel detectors, each composed of 2 × 8 detector modules each of which consists of 32 × 64 lutetium-oxyorthosilicate crystals (1.0 × 1.0 × 10.0 mm3 each). Two configurations for the VP-PET device placement were evaluated: (1) place the two flat-panel detectors at the center of the scanner’s axial FOV below the patient bed; (2) place one flat-panel detector at the center of the first and the last quarter of the scanner’s axial FOV below the patient bed. Sensitivity profiles were measured by moving a point 22Na source stepwise across the scanner’s FOV axially at different locations. To assess the improvement in CRC and lesion detectability by the VP-PET devices, an elliptical torso phantom (31.6 × 22.8 × 106 cm3) was first imaged by the native scanner then subsequently by the two VP-PET geometry configurations. Spherical lesions (4 mm in diameter) having 5:1 lesion-to-background radioactivity concentration ratio were grouped and placed at nine regions in the phantom to analyze the dependence of the improvement in plane. Average CRCs and their standard deviations of the 7 tumors in each group were computed and the receiver operating characteristic (ROC) curves were drawn to evaluate the improvement in lesion detectability by the VP-PET device over the native long axial PET scanner. The fraction of coincidence events between the inserts and the scanner detectors was 13%–16% (out of the total number of coincidences) for VP-PET configuration 1 and 2, respectively. The VP-PET systems provide higher CRCs for lesions in all regions in the torso, with more significant enhancement at regions closer to the inserts, than the native scanner does. For any given false positive fraction, the VP-PET systems offer higher true positive fraction compared to the native scanner. This work provides a potential solution to further enhance the image resolution of a long axial FOV PET scanner to maximize its lesion detectability afforded by its super high effective sensitivity.
Optically stimulated luminescence detectors for dosimetry and LET measurements in light ion beams
Authors: Christensen Jeppe Brage , Muñoz Iván Domingo , Bassler Niels , Stengl Christina , Bossin Lily , Togno Michele , Safai Sairos , Jäkel Oliver , Yukihara Eduardo Gardenali
Published: June 2023

Objective. This work investigates the use of Al2O3:C and Al2O3:C,Mg optically stimulated luminescence (OSL) detectors to determine both the dose and the radiation quality in light ion beams. The radiation quality is here expressed through either the linear energy transfer (LET) or the closely related metric Q
eff, which depends on the particle’s speed and effective charge. The derived LET and Q
eff values are applied to improve the dosimetry in light ion beams. Approach. OSL detectors were irradiated in mono-energetic 1H-, 4He-, 12C-, and 16O-ion beams. The OSL signal is associated with two emission bands that were separated using a pulsed stimulation technique and subjected to automatic corrections based on reference irradiations. Each emission band was investigated independently for dosimetry, and the ratio of the two emission intensities was parameterized as a function of fluence- and dose-averaged LET, as well as Q
eff. The determined radiation quality was subsequently applied to correct the dose for ionization quenching. Main results. For both materials, the Q
eff determinations in 1H- and 4He-ion beams are within 5 % of the Monte Carlo simulated values. Using the determined radiation quality metrics to correct the nonlinear (ionization quenched) detector response leads to doses within 2 % of the reference doses. Significance. Al2O3:C and Al2O3:C,Mg OSL detectors are applicable for dosimetry and radiation quality estimations in 1H- and 4He-ions. Only Al2O3:C,Mg shows promising results for dosimetry in 12C-ions. Across both materials and the investigated ions, the estimated Q
eff values were less sensitive to the ion types than the estimated LET values were. The reduced uncertainties suggest new possibilities for simultaneously estimating the physical and biological dose in particle therapy with OSL detectors.
Investigation of TL and OSL detectors in ultra-high dose rate electron beams
Authors: Motta S , Christensen J B , Frei F , Peier P , Yukihara E G
Published: June 2023

Objective. This work aims at investigating the response of various thermally stimulated luminescence detectors (TLDs) and optically stimulated luminescence detectors (OSLDs) for dosimetry of ultra-high dose rate electron beams. The study was driven by the challenges of dosimetry at ultra-high dose rates and the importance of dosimetry for FLASH radiotherapy and radiobiology experiments. Approach. Three types of TLDs (LiF:Mg,Ti; LiF:Mg,Cu,P; CaF2:Tm) and one type of OSLD (Al2O3:C) were irradiated in a 15 MeV electron beam with instantaneous dose rates in the (1–324) kGy s−1 range. Reference dosimetry was carried out with an integrating current transformer, which was calibrated in absorbed dose to water against a reference ionization chamber. Additionally, dose rate independent BeO OSLDs were employed as a reference. Beam non-uniformity was addressed using a matrix of TLDs/OSLDs. Main results. The investigated TLDs were shown to be dose rate independent within the experimental uncertainties, which take into account the uncertainty of the dosimetry protocol and the irradiation uncertainty. The relative deviation between the TLDs and the reference dose was lower than 4 % for all dose rates. A decreasing response with the dose rate was observed for Al2O3:C OSLDs, but still within 10 % from the reference dose. Significance. The precision of the investigated luminescence detectors make them suitable for dosimetry of ultra-high dose rate electron beams. Specifically, the dose rate independence of the TLDs can support the investigation of the beam uniformity as a function of the dose rate, which is one of the challenges of the employed beam. Al2O3:C OSLDs provided high precision measurements, but the decreasing response with the dose rate needs to be confirmed by additional experiments.
On the Nature of Jets from a Main Sequence Companion at the Onset of Common Envelope Evolution
Authors: Soker Noam
Published: June 2023

I consider a flow structure by which main sequence companions that enter a common envelope evolution (CEE) with giant stars might launch jets even when the accreted gas has a sub-Keplerian specific angular momentum. I first show that after a main sequence star enters the envelope of a giant star the specific angular momentum of the accreted gas is sub-Keplerian but still sufficiently large for the accreted gas to avoid two conical-like openings along the two opposite polar directions. I suggest that the high-pressure zone that the accreted gas builds around the main sequence equatorial plane accelerates outflows along these polar openings. Most of the inflowing gas is deflected to the polar outflows, i.e., two oppositely directed jets. The actual mass that the main sequence star accretes is only a small fraction, ≈0.1, of the inflowing gas. However, the gravitational energy that this gas releases powers the inflow-outflow streaming of gas and adds energy to the common envelope ejection. This flow structure might take place during a grazing envelope evolution if it occurs, during the early CEE and possibly in some post-CEE cases. This study increases the parameter space for main sequence stars to launch jets. Such jets might shape some morphological features in planetary nebulae, add energy to mass removal in CEE and power some intermediate luminosity optical transients.
Toroidal modeling of plasma flow damping and density pump-out by RMP during ELM mitigation in HL-2A
Authors: Zhang N. , Liu Y.Q. , Yu D.L. , Liu Yi , Hao G.Z. , Liu L. , He X.X. , Sun T.F. , Ji X.Q. , Wang S. , Dong G.Q. , Bai X. , Wei Y.L. , Chen W.J. , Sun Y.W. , Jiang M. , Zhang Y.P. , Shi Z.B. , Zhong W.L. , Xu M.
Published: June 2023

Reduction of both the plasma density and toroidal flow speed, due to application of the predominantly n = 1 (n is the toroidal mode number) resonant magnetic perturbation (RMP) for controlling the edge localized mode in the HL-2A tokamak, is numerically investigated utilizing the quasi-linear initial-value code MARS-Q (Liu et al 2013 Phys. Plasmas
20 042503). Simulation results reveal that the neoclassical toroidal viscosity (NTV) due to three dimensional fields plays the key role in modifying the plasma momentum and particle transport in the HL-2A discharge. By comparing the modeling results with the measured density pump-out in the experiment, the electron NTV particle flux model, in combination with the free-boundary condition for the axisymmetric change of the density at the plasma edge, is found to yield the best agreement in terms of both the pump-out level and the overall time scale. Further sensitivity studies show that the simulated density pump-out level is reasonably robust against variations in the model assumptions, including the particle diffusion model and the non-ambipolar versus ambipolar NTV particle flux. The latter however affects the time scale for reaching the steady state solution. Finally, it is found that the plasma edge-peeling response, the NTV torque, as well as the plasma momentum and particle transport, all are sensitive to the toroidal phase difference between the upper and lower rows of the RMP coil currents in HL-2A, with the 30∘ coil phasing producing the minimal side effects on the plasma.
The entropy production of stationary diffusions
Authors: Da Costa Lancelot , Pavliotis Grigorios A
Published: June 2023

The entropy production rate is a central quantity in non-equilibrium statistical physics, scoring how far a stochastic process is from being time-reversible. In this paper, we compute the entropy production of diffusion processes at non-equilibrium steady-state under the condition that the time-reversal of the diffusion remains a diffusion. We start by characterising the entropy production of both discrete and continuous-time Markov processes. We investigate the time-reversal of time-homogeneous stationary diffusions and recall the most general conditions for the reversibility of the diffusion property, which includes hypoelliptic and degenerate diffusions, and locally Lipschitz vector fields. We decompose the drift into its time-reversible and irreversible parts, or equivalently, the generator into symmetric and antisymmetric operators. We show the equivalence with a decomposition of the backward Kolmogorov equation considered in hypocoercivity theory, and a decomposition of the Fokker-Planck equation in GENERIC form. The main result shows that when the time-irreversible part of the drift is in the range of the volatility matrix (almost everywhere) the forward and time-reversed path space measures of the process are mutually equivalent, and evaluates the entropy production. When this does not hold, the measures are mutually singular and the entropy production is infinite. We verify these results using exact numerical simulations of linear diffusions. We illustrate the discrepancy between the entropy production of non-linear diffusions and their numerical simulations in several examples and illustrate how the entropy production can be used for accurate numerical simulation. Finally, we discuss the relationship between time-irreversibility and sampling efficiency, and how we can modify the definition of entropy production to score how far a process is from being generalised reversible.
Mix proportion optimization and early strength development in modified foam concrete: an experimental study
Authors: Shi Minghui , Yin Guansheng , Wei Pengfei , Zhang Jintao , Yang Zhaotong
Published: June 2023

The influence of the single polycarboxylate superplasticizer (PCE) and blending it mixed hydroxypropyl methylcellulose (HPMC) on hardening moulding quality and surface pulverisation of foam concrete was investigated. An orthogonal experimental design was employed to determine the optimum combination of parameters for four property indexes (PIs) in this paper. A multi-index matrix analysis method was used to evaluate the parameter combinations and obtain the overall optimal performance for the PIs. The effect of calcium formate (CaF) on the early compressive strength of modified foam concrete with the most optimal combination in different density grades was also studied. The results indicate that the incomplete cement hydration reaction is the essential cause of pulverisation, which can be alleviated by adding a suitable PCE. Defoaming and precipitation occur when the PCE incorporated exceeds 0.1%, which can be mitigated by the addition of 0.02 to 0.06% HPMC. The orthogonal analysis indicates that the anti-cracking agent has a more substantial effect on the strength of the foam concrete than the thickening agent. The most significant factor of mechanical properties is PP fiber followed by dispersible latex powder (DLP). The optimal combination of foam concrete is 0.06% HPMC, 0.3% DLP, and 0.5% PP fiber. The early compressive strength of foam concrete can be significantly enhanced by increasing the CaF content. However, increasing the density level results in a decrease in the 28-day compressive strength of the foam concrete.
Acute Experiences of Negative Interpersonal Interactions: Examining the Dynamics of Negative Mood and Ambulatory Blood Pressure Responses Among Black and Hispanic Urban Adults
Authors: Zawadzki Matthew J , Graham-Engeland Jennifer E , Robles Patrick L , Hussain Maryam , Fair Emily V , Tobin Jonathan N , Cassells Andrea , Brondolo Elizabeth
Published: June 2023

Background

Negative interpersonal interactions are associated with acute increases in ambulatory blood pressure (ABP). Yet, the mechanisms underlying this relationship are unclear.

Purpose

This study tested whether negative interpersonal interactions predict higher ABP both in the moment and during subsequent observations, and whether increases in negative mood mediate these relations. These associations were tested among Black and Hispanic urban adults who may be at higher risk for negative interpersonal interactions as a function of discrimination. Race/ethnicity and lifetime discrimination were tested as moderators.

Methods

Using a 24-hr ecological momentary assessment (EMA) design, 565 Black and Hispanic participants (aged 23–65, M = 39.06, SD = 9.35; 51.68% men) had their ABP assessed every 20 min during daytime accompanied by an assessment of negative interpersonal interactions and mood. This produced 12,171 paired assessments of ABP and self-reports of participants’ interpersonal interactions, including how much the interaction made them feel left out, harassed, and treated unfairly, as well as how angry, nervous, and sad they felt.

Results

Multilevel models revealed that more intense negative interpersonal interactions predicted higher momentary ABP. Mediation analyses revealed that increased negative mood explained the relationship between negative interpersonal interactions and ABP in concurrent and lagged analyses. Discrimination was associated with more negative interpersonal interactions, but neither race/ethnicity nor lifetime discrimination moderated findings.

Conclusions

Results provide a clearer understanding of the psychobiological mechanisms through which interpersonal interactions influence cardiovascular health and may contribute to health disparities. Implications include the potential for just-in-time interventions to provide mood restoring resources after negative interactions.
The Geopolitics of Infotainment
Authors: Hoffman Lindsay H. , Rotich Gilbert K.
Published: June 2023

Although there is a lack of consensus among political communication scholars on the standard conceptualization of infotainment, scholarship converges on the idea that infotainment describes an admixture of information and entertainment. It is a buzzword used as an umbrella term for sensationalized content, satire, including tabloidization, caricaturization, impersonation, and personalization of political actors. Infotainment is not a unique and isolated genre in and of itself, but a term often used pejoratively to describe the decline and shift away from hard to soft news. This cluster of television programming has made it difficult to discern between information and entertainment content. Significantly, this fusion of entertainment and journalism has gained prominence as a function of exponential changes in the media industry. These trends in political journalism, fueled by the public’s changing patterns in the consumption of political news and the increasing use of the “softer” outlets by political actors to reach the masses, facilitated the cosmetic rise of infotainment. Consequently, we have seen the news becoming more entertaining while the entertainment programs take on politics. Notably, infotainment is contextualized as a tool of geopolitical influence; its uses and gratifications have moved beyond informing and entertaining audiences to become tools of political influence and resistance. Political satire and comedy have been used to interrogate power and create space for political freedom in various corners of the world, used as a soft means of power to transmit culture. Overall, political entertainment has become a means to an end.
Race and Affect in Digital Media Cultures
Authors: Alinejad Donya
Published: June 2023

Media has always been central to the social production and contestation of racial and ethnic difference. The politics of representation has formed the conceptual frame for much of the seminal scholarship examining the role of media in reproducing ideologies of race. Yet, with the advancement of digitally mediated communicative spaces, emerging experiences of interactive social encounters with racial difference compound people’s spatially proximous, “offline” encounters. And the circulation of controversy, together with the changing relationship between counterpublics and mainstream media, further complicates questions of race and media. From online hate speech to hashtagged antiracism movements, ideologies of race and practices of racial and ethnic ordering and discrimination are being reproduced, rethought, and, to some extent, reinvigorated in ways that are unique to the widespread uptake of digital technologies. Race and representation bear revisiting in light of these developments.

In what has been called the “affective turn,” scholars have theorized “nonrepresentational” and affective communications as a way of explaining some of the important developments associated with digital media phenomena, such as online virality and digital attention economies. Affect has helped conceptualize the paracognitive and emotional dimensions of social life, as well as the spatial and material dynamics of mediated experiences of encounter and interaction. Through a discussion of literature at the nexus of affect, media, and race/ethnicity, this article maps and draws relations between longer-running debates on media, representation, and race and more current notions of digital affect and emotion. It suggests that the notion of representation has sustained relevance for understanding how emergent digital media forms produce ideologies of race and ethnic difference.The article also signals where the entwinement of affect and representation suggests productive directions for further understanding of race in relation to a changing range of digital-media technologies and practices.
Psychoanalysis in Rhetorical Theory
Authors: Lundberg Christian
Published: June 2023

The traditions of rhetoric and psychoanalysis share a common interest in speech as an object and grounds for analysis. The two traditions diverge in their approach to speech: rhetoric understands speech to be primarily concerned with the contextual effects of speech as statement; psychoanalysis with speech as symptom. Understanding the points of mutual overlap, reaffirmation, and critique between the two traditions requires an account of how both traditions mobilize the conception of meaning in interpreting and/or analyzing speech. In clarifying the investments bound up with critical work as interpretation and/or analysis in each of the traditions, it is possible to approach the productive points of tension and affinity between the two traditions anew: in doing so, it may also be easier to understand the roles of audience, affect, and form in detailing the conditions through which speech constitutes subjects and identities, and by which it exerts rhetorical effects.
Relational Dialectics Theory
Authors: Scharp Kristina M.
Published: June 2023

Relational dialectics theory (RDT) is a postmodern critical theory of meaning. Based on the writing of Russian philosopher, RDT attunes researchers to the ways that discourses (i.e., ideologies) compete to make meaning of particular semantic objects (e.g., identities, phenomena, processes, etc.). Of note, not all discourses hold the same amount of power. Some discourses are dominant (i.e., centripetal) whereas others are marginalized (i.e., centrifugal). RDT researchers, then, are primarily interested in exploring how these discourses, with unequal power, compete. This focus on the competition of discourses for power and the ability of RDT to call out the ideological forces that disenfranchise some groups while enfranchising others holds promise for practical applications such as debunking misconceptions and better understanding where privilege comes from and how it is perpetuated.

When discourses compete, they might do so within or across a set of utterances. Utterances are turns in talk and serve as the primary unit of analysis in RDT research. Utterances, however, are not standalone entities. Rather, they are connected by different links to form an utterance chain. Some links of the utterance chain pertain to time (what has been said before and what response an utterance can anticipate) whereas the other links of the utterance chain pertain to the relationship level (some pertain to the culture at large whereas other only to an idiosyncratic relationship).

Overall, discursive competition takes place across a continuum of interplay. At one end of the continuum is monologue. Monologue represents the absence of meaning. Next are discursive enactments (i.e., closure) that reinforce the dominant discourse and shut down alternatives (see entry for complete list). Diachronic separation occurs when the dominance of a discourse changes across time. Diachronic separation can take two forms: (a) spiraling inversion or (b) segmentation. Synchronic interplay is next and occurs when two discourses compete within a given utterance. When RDT researchers examine a text for synchronic interplay, they often look to see how a marginalized discourse (a) negates, (b) counters, or (c) entertains the dominant discourse. Finally, on the other end of the continuum of interplay, is dialogic transformation. Dialogic transformation occurs through either (a) discursive hybridity or (b) an aesthetic moment whereby discourses suspend their interplay to create new meanings.

Conducted using RDT’s corresponding method, contrapuntal analysis, researchers using this theory work to disrupt hegemonic, taken-for-granted assumptions about how things are and call attention to voices overlooked in the past. To date, this theory has been taken up primarily by family, interpersonal, and health communication scholars, although many scholars have used this theory throughout the discipline.
Well-being at Work
Authors: Kozusznik Malgorzata , Soriano Aida , Peiró José M.
Published: June 2023

Well-being at work refers to employees’ experience of feeling good and having a sense of fulfillment and purpose. It can be conceptualized from two distinct perspectives grounded in different philosophical traditions: the hedonic view of pleasure, in terms of people’s positive evaluations of their lives, includes positive emotions, satisfaction, and the experience of positive affect, and the eudaimonic view of well-being has to do with personal growth and the sense of meaning. Thus, well-being can be understood as having both pleasurable and meaningful components. Different theoretical frameworks help us to understand the nature of well-being. The most prominent ones are the happy-productive worker thesis, broaden-and-build theory, adaptation-level theory, affective events theory, the collective well-being approach, and self-determination theory. Well-being at work is influenced by several work experiences and working conditions and, in turn, has an effect on the employee’s behavior at work. Finally, well-being can be improved and sustained through initiatives that cover a wide range of fields (physical vs. psychosocial), approaches (prevention vs. promotion), and foci (organizational vs. individual).
Transformational School Leadership to Dismantle Inequitable Systems
Authors: Preis Deirdra
Published: June 2023

A key reason for the failure of U.S. school leaders to challenge systems of inequity is the lack of exposure to the theory and skill development needed to manage the resistance and political challenges that inevitably occur when interrogating unjust traditions of practice. As preparation programs aim to improve their candidates’ future success in addressing inequitable educational access, it is critical that they develop in their students the self-efficacy around relational practices and strategies needed to manage the micropolitics of transformative work. Examining how transformative K–12 school leaders effectively challenge structural inequities and manage to sustain their leadership positions during turbulent times can help to inform such curricular and instructional revisions. Some of the key practices identified by successful transformative K–12 leaders include engaging in reflection around their positionality, developing racial literacy, effectively facilitating shared visions and collective responsibility for social justice advocacy, building the capacity of stakeholders, developing critical alliances through transparent and authentic community involvement, and participating in supportive professional peer networks that offer ongoing reflection, study, and support. By providing such content and skill practice, and ensuring that instruction and mentoring are provided by faculty who are experienced in transformative leadership, leader candidates can be better prepared for the realities of this challenging work, increasing the likelihood that they will act transformatively upon assuming school leadership roles.
Teach For America
Authors: Smith Spencer J.
Published: June 2023

Since its founding in 1989 by then–college student Wendy Kopp, Teach For America (TFA) has influenced education policy and public perceptions of schooling both in the United States and abroad. By placing recent college graduates as full-time teachers in schools located in low-income communities, TFA attempts to solve educational inequity. This work has often met with resistance from teacher educators and traditional teacher preparation programs. Central to this resistance is the brevity of TFA’s training. TFA recruits, called corps members, undergo a 6-week training the summer before stepping into a K-12 classroom they control. Over 3 decades, TFA has responded to some of these criticisms and has changed. Even though TFA teachers make up a small proportion of teachers in the United States, scholars still study TFA since many elements of contemporary U.S. schooling are encapsulated within the TFA program. Understanding TFA’s history is necessary for the way scholars and educationists engage with the organization to think about issues in education, including the effect of teachers on student achievement, the standardization of neoliberal schooling, appropriate responses to academic achievement gaps, and the use of culturally responsive pedagogies and cultural competency in classrooms of historically marginalized students. Importantly, these issues are not just entirely theoretical when TFA actively influences public policy and TFA alumni create new school networks, lead large school districts, and become education scholars themselves. Additionally, TFA’s international expansion in 2007 means that TFA’s influence can be felt globally.
Student Voice, Inequalities, and Class
Authors: Finneran Rachel , Mayes Eve , Black Rosalyn
Published: June 2023

It is well-understood that systems of education tend to disproportionately benefit already advantaged social groups. Students have been positioned in recent reform efforts as agents with the right to be involved in decision-making on an increasing range of issues related to their education, in practices commonly termed “student voice” in policy, practice, and research. Student voice has been argued to be a mechanism to intervene in educational inequalities and a means to enhance students’ choices at school. Student voice is frequently represented as a neutral proposition: that is, that students’ involvement in decision-making will directly benefit both the school and the students themselves. This apparently neutral proposition elides how, in practice, some students may benefit from experiences of “student voice” more than others.

Critiques of student voice, as well as contemporary calls for a return to class analysis in education, compel attention to the potential ways that student voice practices can aggravate existing inequalities. Classed dynamics contour even well-intentioned attempts to intervene in educational inequalities. The dynamic experience of class has shifted in relation to student voice across contexts and over time, particularly in individualistic, market-driven educational systems structured by the rhetoric of “choice.” Further research into the shifting nature of class in relation to student voice may include longitudinal processes of “studying up” to understand how student voice can be mobilized to cultivate educational advantage and distinction in class-privileged schooling contexts. What is also needed is a renewed uptake of the concept of class consciousness in student-voice practice—that is, beyond voice as a strategy to personalize individual students’ learning and toward enactments of student voice as collective work—if student voice is to disrupt the reproduction of structural inequalities through schooling.
An Overview of Historical Transitions in Politics of Education in Spain
Authors: Jover Gonzalo , González-Delgado Mariano
Published: June 2023

Politics of education constitutes a major line of research in Spain in recent years. This interest is the result of a long process. Enlightened thought and the emergence of new ideas led to thinking about the need to develop a national education system. The 19th century witnessed the birth of just such a system, along with the unfinished debate between liberals and conservatives on who should control education (church or state) and how it should be funded. By the 20th century, the education system had become one of the main resources for achieving social modernization in Spain and grew accordingly. Despite the Spanish Civil War (1936–1939), this push for modernization carried on into the Franco dictatorship, with the typical peculiarities of a totalitarian regime. By the end of World War II, the Spanish education system was characterized by following the development of educational policies inscribed in the model of Western societies, or what has been called “global governance in education.” This conception of education was continued during the restoration of democracy in 1978. Despite its intention of configuring an education system based on the agreement between the major political parties of the day, the Constitution of 1978 did not manage to end the “school war,” which has caused considerable instability in the system. Since the end of the 20th century, the Spanish education system has been inserted in the context of international trends such as the resizing of political spaces, the push of the neoliberal global economy, and the move toward multicultural societies. The battle of statistics, figures, and scores has led to a supposed depoliticization of the debate. In face of this alleged depoliticization, an argument can be made in favor of resituating the politics of education as a field of knowledge that concerns social aspirations forged in the course of history and ethics.
Inland Trade in the Mughal Empire
Authors: Jain Shalin
Published: June 2023

The Mughal rule had manifold implications in all spheres of life in India, including the economic one. During the peak period of imperial power (17th century), inland trade underwent a transformation in volume, commodities, and organization. The historiography of inland trade has seen various shifts in the last four decades. The initial views of an autocratic state have been overtaken by new research recognizing the state’s role in facilitating trade in alliance with nobility and other elite groups. The autonomous function of trading activities and merchant groups is now widely acknowledged. Authoritative attitudes and attempts at extraction did sometimes impinge on the expansion of trade and commerce, but subject to that qualification, individual action had agency. The pattern of local, regional, and inter-regional trade being facilitated by urbanization, goods transport, and other related services shows that commercial transactions in the commodities of daily use, as well as luxurious items, were constantly increasing. Here goes a narrative history, a tour of the historiography, and a discussion about the communities engaged in commercial transactions.
Central Asia between Empires: New Research on the 18th and 19th Centuries
Authors: Pickett James
Published: June 2023

Central Asia’s 18th and 19th centuries marked the definitive end of the nomadic empires that characterized the region’s geopolitics for over three millennia before the advent of colonialism. Although it is open to debate which polity was the last “empire of the steppe,” a strong case can be made for the Junghar confederacy, which contested the Qing Empire of China for dominance in Eurasia in the 17th and 18th centuries—ultimately unsuccessfully. The Junghars owed their early success to a combination of new gunpowder technology and nomadic military organization, and the fragmented city-states that emerged from Nadir Shah Afshar’s empire (1736–1747)—such as Bukhara, Khiva, and Khoqand—relied even more on musketeer infantry units composed of individuals without ties to the local Turkic military elite. The emergent fiscal-military states that characterized Central Asia on the eve of colonial conquest were thus quite novel in terms of structural power dynamics, yet thoroughly Turko-Perso-Islamic in terms of symbolism, law, and patrimonialism.

This period also witnessed what was in many ways the apex of Persianate high culture, building on traditions with roots stretching back to the Timurid period and earlier. Sufism in all of its forms became mainstream. Intellectual elites were polymathic, simultaneously mastering jurisprudence, poetry, medicine, occult sciences, and more. Vernacularization, particularly in literary Central Asian Turki, deepened these currents and carried them to new audiences. The new city-state dynasties competed with one another to build up educational centers to support all of these cultural forms.

Many of these cultural, social, and even political forms persisted under colonialism, even as the pace of change sped up. Some of the precolonial dynasties persevered under indirect colonial rule. Sufi brotherhoods and Islamic learning expanded, only to be snuffed out or transformed in the Soviet period. Only at the very end of the 19th century did colonial modernity—in the form of large-scale cotton cultivation, new understandings of national identity, print culture, and steam-propelled transport—begin to make significant inroads.
Women in Chad
Authors: Rosenhart Eline , Remadji Guidimbaye Germaine
Published: June 2023

Chad, a landlocked state in the heart of Africa, encompasses an area of 495,755 square miles (1,284,000 km2) and contains a population of 15 million people, with an estimated 180 different people groups. Women have played an important role in Chad’s history and society. In the precolonial period (16th century–1900), Chadian women played an essential part in the physical labor activities that provided for the livelihood of the community, yet the majority of women held limited decision-making power. In the courts of precolonial kingdoms, however, certain women of high rank held important political functions. During the period of French colonial rule (1900–1960), no significant effort was made to promote the status of women. Moreover, certain colonial policies geared toward generating revenue inflicted disproportionally heavy burdens on Chadian women. Education for women in colonial schools was an exception rather than a rule. Nevertheless, a small number of women were able to take advantage of the opportunities they did receive to carve out a space for themselves and become leaders in independent Chad (1960– ). Those belonging to the dominant political party mostly aimed their attention at improving women’s rights, while others in the opposition focused on the larger battles against colonialism, authoritarianism, nepotism, and the blatant disregard for human rights in Chad. In early 21st-century Chad, women are still underrepresented in all spheres of public life. Sexual and gender-based violence against women has become commonplace, contributing to the mounting gender inequality that continues to pervade and shape Chad.