Feedback Research Articles

Using an evidence-informed reflection tool to develop understandings of feedback talk

ABSTRACT Research-based and practical reflection tools can enable systematic analysis of practice and contribute to deeper understandings of classroom processes. An empirically based, evidence-informed reflection tool was developed to support teachers to recognise feedback talk and how it is built into classroom interactions. The tool, titled the feedback talk framework, enabled teachers to reflect on their feedback talk and effect changes in practice and feedback literacy. The feedback talk framework was refined through a survey and semi-structured interviews with teachers for use as a reflection tool and resulted in three overarching feedback talk themes: informing, confirming and validating, and questioning. Results illuminated how teachers used the tool to identify and reflect on feedback talk, strengthening our argument that using an empirically derived feedback talk framework can support evidence-based approaches to teacher reflection. Suggestions and implications for the utility of the reflection tool in a range of contexts are then provided.

The International Division of Finance: reassessing the peripheral condition in a financialised capitalism

ABSTRACT Based on the Latin American structuralist theory, but advocating for a need of framing the discussions in the current historical context – characterised by financialisation and financial globalisation –, this article investigates the centre-periphery configuration of the global economy with the focus on the monetary-financial sphere. More specifically, it aims to analyse the role of the peripheral countries for the current International Monetary and Financial System (IMFS). In a dialogue with the discussions related to the International Division of Labour (IDL), the article thence proposes and conceptualises the International Division of Finance (IDF), as well as its corresponding structural differentiation and structural tendency. It argues that the IDF is not accidental, but plays a fundamental role in the modus operandi of the reproduction of wealth in international financial circuits. Through an empirical analysis with data from 212 countries for the period 2000-23, the article demonstrates a structural tendency of transfer of wealth from periphery to central countries. Along with the IDL (in its contemporary format), it generates a ‘double-capture of wealth’. As a result, the IDL and the IDF have feedback effects, deepening the subordination, the lack of autonomy for economic policy and the vulnerability of peripheral countries.

Forest fire size amplifies postfire land surface warming

Climate warming has caused a widespread increase in extreme fire weather, making forest fires longer-lived and larger1–3. The average forest fire size in Canada, the USA and Australia has doubled or even tripled in recent decades4,5. In return, forest fires feed back to climate by modulating land–atmospheric carbon, nitrogen, aerosol, energy and water fluxes6–8. However, the surface climate impacts of increasingly large fires and their implications for land management remain to be established. Here we use satellite observations to show that in temperate and boreal forests in the Northern Hemisphere, fire size persistently amplified decade-long postfire land surface warming in summer per unit burnt area. Both warming and its amplification with fire size were found to diminish with an increasing abundance of broadleaf trees, consistent with their lower fire vulnerability compared with coniferous species9,10. Fire-size-enhanced warming may affect the success and composition of postfire stand regeneration11,12 as well as permafrost degradation13, presenting previously overlooked, additional feedback effects to future climate and fire dynamics. Given the projected increase in fire size in northern forests14,15, climate-smart forestry should aim to mitigate the climate risks of large fires, possibly by increasing the share of broadleaf trees, where appropriate, and avoiding active pyrophytes.

The generation of a multiphase medium in ‘Splash’ bridge systems: towards an understanding of star formation suppression in turbulent galaxy systems

ABSTRACT Cloud–cloud collisions in splash bridges produced in gas-rich disc galaxy collisions offer a brief but interesting environment to study the effects of shocks and turbulence on star formation rates in the diffuse intergalactic medium, far from the significant feedback effects of massive star formation and active galactic nucleus. Expanding on our earlier work, we describe simulated collisions between counter-rotating disc galaxies of relatively similar mass, focusing on the thermal and kinematic effects of relative inclination and disc offset at the closest approach. This includes essential heating and cooling signatures, which go some way towards explaining the luminous power in H$_2$ and [C ii] emission in the Taffy bridge, as well as providing a partial explanation of the turbulent nature of the recently observed compact CO-emitting clouds observed in Taffy by the Atacama Large Millimeter Array (ALMA). The models show counter-rotating disc collisions result in swirling, shearing kinematics for the gas in much of the post-collision bridge. Gas with little specific angular momentum due to collisions between counter-rotating streams accumulates near the centre of mass. The disturbances and mixing in the bridge drive continuing cloud collisions, differential shock heating, and cooling throughout. A wide range of relative gas phases and line-of-sight velocity distributions are found in the bridges, depending sensitively on initial disc orientations, and the resulting variety of cloud collision histories. Most cloud collisions can occur promptly or persist for quite a long duration. Cold and hot phases can largely overlap throughout the bridge or can be separated into different parts of the bridge.

Effect of comorbid psychologic and somatic symptom trajectories on early onset substance use among U.S. youth in the ABCD study

BackgroundAdolescent substance use (SU) is often motivated by a desire to alleviate undesirable symptoms. To test the self-medication hypothesis, we examined associations between comorbid psychologic and somatic symptom trajectories across early adolescence and early onset SU. MethodsUsing Adolescent Brain Cognitive Development Study® data, we differentiated youth who reported no SU at baseline based on their comorbid anxiety, depression, pain, somatic and somnolence symptom trajectories. The outcome, early onset SU (by age 13–14 years) was derived from self-reported alcohol (≥full drink), tobacco (full regular/e-cigarette), marijuana, or other drug use over 5 years. Results8311 participants were classified with Asymptomatic (27.8 %), Low/stable (39 %), Moderate/persistent (25.3 %) or High/worsening trajectories (7.9 %) from age 9.97 ± 0.74 to 13.57 ± 0.88 years. Early onset SU was 56 % higher for Moderate-High compared to Asymptomatic-Low symptom trajectory groups (12.5 % vs. 8.5 %; OR 1.56 [95 % CI 1.33, 1.79]). Adjusted for covariates, the High/worsening group was more likely than the Asymptomatic group to report use of any substance (adj.OR 2.13 [95 % CI 1.40, 3.25], Alcohol (adj.OR 2.80 [95 % CI 1.56, 5.02]), Tobacco (adj.OR 2.09 [95 % CI 1.23, 3.55]), and Marijuana (adj.OR 2.33 [95 % CI 1.36, 3.99]). Longitudinal, time-lagged analyses revealed potential feedback effects of earlier depression on subsequent SU, and earlier SU on later depression (p < 0.001). ConclusionHigher comorbid symptom trajectories emerging in late childhood increased the likelihood of early onset SU. Since negative feedback loops may contribute to symptom persistency, ongoing and potentially harmful SU for at-risk youth, addressing comorbid symptoms that emerge during late childhood is warranted.

Home Team Effect and Opinion Network after the Sewol Ferry Disaster: A mixed-method study of the influence of symbol and feedback on liberal versus conservative newspapers’ negative opinions

Studies on the symbol and feedback effects on the opinion based on the theory are lacking. Acknowledging that the media express their stance and opinion and that negative opinions are critical to policy change, this paper fills the gap in the literature by illustrating and comparing the effects of emotional and cognitive symbols and positive and negative feedback on the liberal and conservative newspapers’ negative opinions of South Korean President Park Geun-hye’s administration (Park administration) after the Sewol Ferry sank. This study used qualitative and quantitative methods to analyze the archival data, including 424 newspaper editorials and economic data published from April to December 2014. Multiple regression analyses were conducted following a content analysis of newspaper editorials, and network analysis was used to analyze the data. The results mostly supported the hypotheses that symbols and feedback affect the negative opinion on the political discourse, with new findings that deviate from the existing theories. The emotional symbols exerted a stronger influence on the negative opinion compared to cognitive symbols, regardless of the newspaper’s stance. The political system’s response to the positive and negative feedback was not definite; instead, it varied depending on the situation and newspaper perspective. The liberal newspaper responded to symbols and feedback more sensitively compared to the conservative one under the conservative administration. The conservative newspaper expressed more lenient negative opinions towards the conservative administration than the liberal newspaper, supporting the home team effect. These findings have practical and theoretical implications for future studies, highlighting the application of opinion networks in social science.

Snowmelt duration controls red algal blooms in the snow of the European Alps

Algae populate multiple habitats, including snow and ice, where they can form red blooms. These decrease snow albedo, accelerating snowmelt and potentially feeding back on snow and glacier decline caused by climate change. Quantifying this feedback requires the understanding of bloom evolution with climate change. Little, however, is known about the drivers of red snow blooms. Here, we develop an algorithm to analyze 5 y of satellite data from the European Alps and separate bloom occurrences from similarly colored Saharan dust depositions. In a second step, we combine the occurrences of blooms with meteorological data and snow simulations to identify the drivers of blooms. Results show that the upward migration of algae from the ground and blooming requires the presence of liquid water throughout the whole snow column for at least 46 d. Our limited data suggest that moderate dust amounts provide nutrients favorable to bloom, whereas large dust amounts hasten snowmelt and reduce its duration below the threshold required for blooming. Over the period studied, blooms cover 1.3% of the area above 1,800 m elevation, advancing the snow melt-out date by 4 to 21 d in these areas. Under warmer climates, maximum snow mass will decrease whereas snowmelt duration, that controls algal blooms' occurrences, is less sensitive to global temperature increase. In this respect, the impact of bloom on snowmelt will either remain stable (RCP4.5) or decrease (RCP8.5). Algal blooms in the Alps therefore do not constitute a positive climate feedback.

Spontaneous Molecular Bromine Production in Sea-Salt Aerosols.

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea-salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br-) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br-, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton-electron transfer process at the air-water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br- and the production of Br2. The estimated gaseous Br2 production rate was up to 1.55×1010 molecules cm-2 ⋅ s-1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br- activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br- activation. Our findings highlight the crucial role of the proton-electron transfer process in Br2 production; here, H3O+ facilitates the activation of Br- by O2, serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity.

Effect of structural evolution and orientation behavior on optical properties of iodine-dyed PVA film during uniaxial stretching

In the process of preparing polarizing film, based on the research on the influence of the initial condensed structure of Poly (vinyl alcohol) (PVA) film on the dyeing and stretching process, the connection between the structure and performance of polarizing film is established, which is more conducive to understanding the post-processing process of solution casting molding of optical grade PVA film and the optimization of subsequent dyeing and stretching process. In this paper, PVA film with an appropriate swelling degree were selected for dyeing treatment, and the evolution of the condensed structure during stretching was studied in detail. The work also examined the formation and orientation of PVA-iodine complexes and the feedback effect of complex formation on the structural evolution of the film, with the goal of establishing the relationship between stretching ratio, structure, and performance of the polarizing film. The results show that the dyeing process inhibits the recrystallization of the PVA film during uniaxial stretching. However, the PVA-iodine complexes formed act as "anchors" to stabilize the oriented microfiber network, reducing the critical strains (εw and εs) required for the PVA film to enter the strain-hardening zone. Furthermore, as strain increases, the content of polyiodide ions and PVA-iodine complexes in the dyed PVA film also increases, especially making the formation of long iodide chains (I5−) and PVA-I5− complex more sensitive. Additionally, with increasing strain, both the transmittance and degree of polarization of the dyed PVA film improve, reaching optimal values in the strong strain-hardening zone (>εs). This indicates that εs is the minimum critical strain required to ensure optimal polarization performance of the film in the visible light region.

Disentangling the effects of meteorology and emissions from anthropogenic and biogenic sources on the increased surface ozone in Eastern China

China's Clean Air Actions have substantially improved ambient PM2.5 air quality since 2013. However, ozone (O3) pollution in urban areas has worsened in recent years, particularly in the eastern region. The formation of O3 in these high emission areas is highly complex and regulated by numerous factors. Utilizing the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem), this study conducted a comprehensive analysis through nine sensitivity experiments for the years 2013 and 2017, aimed at disentangling the relative contributions of major factors (e.g., meteorological factors, anthropogenic emissions, biogenic emissions, and aerosol feedback mechanisms) to the observed O3 concentration trends in Jiangsu, a developed region of China with increasing trend of O3 level. Our findings indicate a pronounced increase in mean daily maximum 8-h average (MDA8) O3 levels in the economically vibrant southern Jiangsu, contrasted with a decrease in the less developed northern regions. The study identifies anthropogenic emissions change as the primary driver of O3 variations, with significant impacts also attributed to meteorological conditions and aerosol feedback effects, while biogenic emission shifts play a lesser role. In terms of meteorological factors, we discovered that the alteration in meteorological thermal factors (enhanced solar radiation and temperatures) in 2017, compared to 2013, exerted a more pronounced influence on the formation of O3 than the change in thermally driven dynamic factors (boundary layer height and wind speed). Moreover, the study observes a shift in O3 formation sensitivity from VOC-sensitive to transitional or NOX-sensitive regimes, signifying a notable transformation in the regional atmospheric chemistry conducive to O3 generation. Aerosol feedback effects, through complex pathways including photolysis rate alterations and modifications in the vertical O3 distribution, further compound the challenge of mitigating O3 levels. Our research underscores the necessity for adaptive, region-specific strategies to mitigate O3 pollution, providing potential insights for policymakers to formulate effective control measures.

Persistent unilateral action

Abstract Many believe that weaker legal constraints make unilateral action easier to reverse than legislation. Yet in some cases, unilateralism survives a successor's determined opposition. I argue that legislative persistence and unilateral transience may arise not only from differences in legal status but also from a selection effect: unilateralism and subsequent rescission can both stem from weak underlying policy-demanding groups. But if unilateralism itself alters the landscape of group power through policy feedback effects, it can survive a purportedly opposed new president. An example is the Trump Administration's failure to depart from the Obama Justice Department's lax stance on cannabis. Weak constituents’ policy demands may thus need to rely on a sympathetic president's unilateral action to begin a feedback loop, subsequently softening opposition. This paper therefore identifies unilateral action as a key tool for shifting policy in an enduring way, explaining its success or failure in terms of interest group power.

Adaptation of mental health first aid guidelines for eating disorders for Iran

BackgroundThis study aimed to adapt mental health first aid guidelines to support individuals with or at risk of developing eating disorders in Iran. This adaptation seeks to enhance the support available for the Iranian population dealing with these disorders.MethodsWe employed the Delphi expert consensus method, utilizing two panels: health professionals (n = 37 in the first round; n = 29 in the second) and individuals with lived experience (n = 20 in the first round; n = 18 in the second). The health professionals panel was selected from the graduates of various eating disorders associated scientific fields who had a history of providing services to or conducting research on people with eating disorders, and the lived experience panel had a history of eating disorders themselves or in their family. The panel of individuals with lived experience included those who had personal or familial histories of eating disorders. Efforts were made to ensure cultural, gender, and age diversity in the selection of panel members. Panellists rated the importance of each item for inclusion in the guidelines for Iran based on the English-language Mental Health First Aid guidelines for eating disorders. Items deemed essential by at least 80% of both panels were included in the final guideline. Additionally, panel members were invited to suggest any missing items.ResultsA total of 57 participants took part in the first round of the survey, and 47 participated in the second round. In the first round, 204 items across 11 categories were assessed, with 174 items endorsed by the panels. Thirteen items were re-scored in the second round, and 17 items were rejected. Participants suggested 11 new items in the first round. In the second round, 18 out of 24 items were endorsed, while six were rejected. Ultimately, 192 items were incorporated into the Iranian guidelines.ConclusionsThe adaptation process considered Iran's social and cultural characteristics, including the stigma associated with mental health disorders, religious beliefs and rituals such as fasting, linguistic differences between English and Farsi, distrust of strangers, the influence of friends and family, differences in food access, and low mental health literacy. We recommend piloting the adapted guidelines in high schools, universities, and non-governmental organizations to evaluate their feasibility and effectiveness in real-world settings. Furthermore, it is essential to establish mechanisms for feedback, update content based on the latest evidence, and collaborate with the media to promote educational programs and public participation.

The Composition and Diversity of Soil Microbial Communities Associated With the Invasive Plant Solidago canadensis Vary Across Locations and Time Since Invasion

ABSTRACTAimPrevious local‐scale research (within plots or landscapes) has shown that invasive plants can alter the composition and diversity of soil microbial communities, with potential feedback effects on their own invasion success. However, the broader ecological patterns of these interactions across different invasion timescales and geographic regions remain poorly understood. This study investigated whether the composition and diversity of soil microbial communities associated with Solidago canadensis (Canada goldenrod) invasion vary across both population residence times and geographic locations.LocationSouth‐eastern China.TaxonSoil fungal and bacterial communities and S. canadensis.MethodsWe collected rhizospheric soil of S. canadensis, nonrhizospheric soil and adjacent uninvaded soil from each of 36 populations of S. canadensis with varying residence times (8–89 years), totalling 108 samples. We extracted DNA from these samples and sequenced the V3–V4 region of the bacterial 16S rRNA gene and the ITS2 region of the fungal rDNA. We analysed the DNA sequences to assess whether variation in α‐diversity, β‐diversity, arbuscular mycorrhizal fungi (AMF) richness and the ratio of AMF to plant pathogens in the soil microbial communities varied with S. canadensis population residence time, latitude and longitude.ResultsThe α‐diversity and β‐diversity of soil fungal and bacterial communities significantly varied with S. canadensis residence times, latitude and longitude. In locations where S. canadensis had been established for longer periods, there was an increase in AMF richness and a decrease in plant pathogens in the rhizospheric soil. Fungal diversity in rhizospheric soils was positively correlated with longitude, while bacterial diversity in rhizospheric and nonrhizospheric soils was positively correlated with both latitude and longitude.Main ConclusionsThese findings indicate that the time since invasion and geographical location can both significantly influence the composition and diversity of soil microbial communities associated with invasive plant species.

Understanding the effectiveness of automated feedback: Using process data to uncover the role of behavioral engagement

In the last couple of years, feedback research has shifted towards a feedback-as-process approach, taking a learner-centered perspective and focusing on the proactive role of the learner in feedback effectiveness. Process measures can provide new insights into the role of the learner by making learners’ actual behavioral engagement visible. We conducted an experimental study, comparing two groups (feedback vs. no feedback) of English-as-a-foreign-language learners in lower secondary schools (N = 189). The learners completed a writing task and revised it with or without feedback. A second writing task served as a transfer task. Performance was automatically assessed using a scoring algorithm. To determine the level of learners’ behavioral engagement during the text revision, we used the revision time and the edit distance (i.e., a similarity measure) as behavioral measures. Our analyses showed a positive effect of feedback on text revision. We found a full mediation of the effect of feedback on text revision through revision time with an estimated portion of mediation (POM) of .63∗∗∗ and a partial mediation of the feedback effect on text revision through the edit distance with a POM of .30∗∗. We did not find significant mediation effects of either engagement variable regarding performance in a transfer task. Our findings contribute to the understanding of feedback effectiveness, highlighting the central role of learner engagement in the feedback process.

The effects of stellar and AGN feedback on the cosmic star formation history in the simba simulations

ABSTRACT Using several variants of the cosmological simba simulations, we investigate the impact of different feedback prescriptions on the cosmic star formation history. Adopting a global-to-local approach, we link signatures seen in global observables, such as the star formation rate density (SFRD) and the galaxy stellar mass function (GSMF), to feedback effects in individual galaxies. We find a consistent picture: stellar feedback mainly suppresses star formation below halo masses of $M_{\rm H} = 10^{12} \rm \, {\rm M}_{\odot }$ and before $z = 2$, whereas AGN feedback quenches the more massive systems after $z = 2$. Among simba’s AGN feedback modes, AGN jets are the dominant quenching mechanism and set the shape of the SFRD and the GSMF at late times. AGN-powered winds only suppress the star formation rate in intermediate-mass galaxies ($M_{\rm \star } = 10^{9.5 - 10} \rm \, {\rm M}_{\odot }$), without affecting the overall stellar mass-assembly significantly. At late times, the AGN X-ray feedback mode mainly quenches residual star formation in massive galaxies. Our analysis reveals that this mode is also necessary to produce the first fully quenched galaxies before $z=2$, where the jets alone are inefficient. These initially highly star-forming galaxies contain relatively large black holes, likely strengthening the X-ray-powered heating and ejection of gas from the dense, central region of galaxies. Such extra heating source quenches the local star formation and produces a more variable accretion rate. More generally, this effect also causes the break down of correlations between the specific star formation rate, the accretion rate and the black hole mass.

Holocene aeolian environmental dynamics in fixed and semi-fixed deserts over the arid Central Asia revealed by comprehensive sand-dune records

Fixed and semi-fixed deserts are widely distributed in arid Central Asia (ACA). Environmental changes in these deserts can affect the regional radiation balance, climate dynamics, and global climate through a series of feedback effects. This study analyzed luminescence dating from 37 sites, with a particular focus on dendritic dunes (a pattern of vegetated linear dunes) and the ancient dunes beneath them in the Gurbantunggut Desert and yielded the following insights. (1) Primary ridges of dendritic dunes originated approximately 1.0 ka, whereas secondary ridges predominantly formed at 8.5 ± 0.3 ka. The formation of the underlying ancient dunes commenced at least 11.0 ± 0.5 ka and ended between 8.5 ± 0.3 ka and 8.2 ± 0.4 ka. (2) During the Holocene, the Gurbantunggut Desert underwent two distinct environmental phases. From 11.7 ka to 8.1 ± 0.1 ka, the region was characterized by vigorous aeolian activity, marked by the prevalence of mobile dunes. Conversely, the period from 8.1 ± 0.1 ka to 0 ka exhibited substantial environmental amelioration, with limited aeolian activity and the intermittent partial development of vegetated linear dunes. (3) A comprehensive analysis of the principal factors affecting regional aeolian activity revealed that at 11.7 ka–8.1 ± 0.1 ka, moisture (precipitation) and near-surface wind intensity primarily governed aeolian activity in the Gurbantunggut Desert. At 8.1 ± 0.1 ka–0 ka, aeolian activity was mainly influenced by moisture (precipitation), near-surface wind intensity, and external sand supply. (4) Similar patterns of Holocene aeolian activity were observed in the fixed Bayanbulak, Karakum, and Kizil Kum Deserts within the ACA. On a suborbital scale, winter insolation served as the primary driving factor, along with the ice volume and atmospheric CO2 concentration. These factors collectively controlled regional winter temperatures, which determined moisture (precipitation) and near-surface wind intensity by affecting the winter westerlies and Siberian High, ultimately controlling regional aeolian activity.

Partisan Politics and Feedback Effects: Comparing Defamilialization by Center-Right Parties across Six Familistic Countries

Partisan Politics and Feedback Effects: Comparing Defamilialization by Center-Right Parties across Six Familistic Countries

Does Longer Tenure Mean Greater Ability? Deep-Rooted Politics and Migration in Rural China

This study examines the political motivations behind changes in labor migration rates in Chinese villages. Using data from the China village survey, we estimate the impact of the tenure gap between the village committee director and party branch secretary on village labor migration rates. We find that within the dual power structure of villages, a longer political tenure for the secretary relative to the director significantly suppresses village labor migration rates, while a shorter tenure significantly promotes them. IV estimation supports the causal interpretation found by OLS estimation. This mechanism of causality is associated with vested interests stemming from ambiguous ownership, having a director or secretary with a longer political tenure tends to bias these interests towards villagers or township authorities. Other accompanying effects of the tenure gap should not be ignored, including the amplification effect of the non-laboring population, the feedback effect of labor, and the shrinkage effect of outsiders. This causal relationship is heterogeneous, the dual role analysis shows that the structure and stance of village leaders will affect the strength of the causal relationship, and the regional heterogeneity analysis shows that economic factors that drive village labor migration may be more important than political factors.

Mechanisms of ROS-mediated interactions between Bacillus aryabhattai LAD and maize roots to promote plant growth

BackgroundPlant growth-promoting rhizobacteria (PGPR), as a group of environmentally friendly bacteria growing in the rhizosphere of plants, play an important role in plant growth and development and resistance to environmental stresses. However, their limited understanding has led to the fact that their large-scale use in agriculture is still scarce, and the mechanisms by which beneficial bacteria are selected by plants and how they interact with them are still unclear.MethodIn this study, we investigated the interaction between the auxin-producing strain Bacillus aryabhattai LAD and maize roots, and performed transcriptomic and metabolomic analyses of Bacillus aryabhattai LAD after treatment with maize root secretions(RS).ResultsOur results show that there is a feedback effect between the plant immune system and bacterial auxin. Bacteria activate the immune response of plant roots to produce reactive oxygen species(ROS), which in turn stimulates bacteria to synthesize IAA, and the synthesized IAA further promotes plant growth. Under the condition of co-culture with LAD, the main root length, seedling length, root surface area and root volume of maize increased by 197%, 107%, 89% and 75%, respectively. In addition, the results of transcriptome metabolome analysis showed that LAD was significantly enriched in amino acid metabolism, carbohydrate metabolism and lipid metabolism pathways after RS treatment, including 93 differentially expressed genes and 45 differentially accumulated metabolites.ConclusionOur findings not only provide a relevant model for exploring the effects of plant-soil microbial interactions on plant defense functions and thereby promoting plant growth, but also lay a solid foundation for the future large-scale use of PGPR in agriculture for sustainable agricultural development.

Carbon emission allowances and Nordic electricity markets: Linkages and hedging analysis

Unlike previous studies which tend to consider only return linkages between European emission allowances and electricity markets, this paper examines return and volatility linkages between the two markets and importantly conducts a hedging analysis. Using a dynamic conditional correlation model and daily price data covering European emission allowances and Nord Pool electricity markets from 28th January 2009 to 22th February 2022, which comprise the second and third phases of the European emission allowances trading system, the main results are summarized as follows: Firstly, volatility and returns flow from the Nordic electricity market to the European emission market, with no evidence of a feedback effect, suggesting that rapid changes in demand for electricity may have forced producers to ramp up carbon-intensive facilities. Secondly, the conditional dynamic correlation between the two markets is weak but varies with time, and its sensitivity to crisis periods is noted. Thirdly, the hedging analysis indicates that Nordic electricity market participants can lower their downside risk by including carbon emission allowances in their portfolios, as evidenced by the effectiveness of hedging returns of the Nordic electricity markets with European allowances, irrespective of the COVID-19 sub-periods.