bluuebunny/crossref_metadata_2025 huggingface dataset:
General practitioner workforce sustainability to maximise effective and equitable patient care: a realist review
Authors: Owen-Boukra Emily , Burford Bryan , Cohen Tanya , Duddy Claire , Dunn Harry , Fadia Vacha , Goodman Claire , Henry Cecily , Lamb Elizabeth I , Ogden Margaret , Rapley Tim , Rees Eliot L , Royer-Gray Etienne , Vance Gillian , Wong Geoff , Park Sophie
Published: January 2025

Abstract Background: Global and United Kingdom (UK) primary care face significant General Practitioner (GP) workforce shortages. Worldwide strategies to address this issue include the introduction of additional healthcare professionals and increasing technology utilisation, to reduce GP workload. However, whether these strategies can sustain the GP workforce remains unclear. Our review examines the factors that sustain and enable GPs to flourish. Aim: To examine how general practice work and healthcare systems support GP workforce sustainability and effective and equitable patient care. Design & setting: A realist review of existing empirical and grey literature. The search strategy encompassed six electronic databases. Method: Realist synthesis involved (1) finding existing theories, (2) searching for evidence, (3) selecting articles, (4) extracting data, and (5) synthesising evidence/drawing conclusions. Context-Mechanism-Outcome Configurations were developed using extracted data and patient and public involvement/stakeholder suggestions to refine our programme theory. Results: 168 documents were included. Findings underscore the importance of meaningful work and engagement; relationships across individuals, organisations, and communities; and learning and development. We emphasise the need for congruence between GPs` core values and their work; cumulative-knowledge building; system agility; psychological safety; and direct human connections. Conclusion: General practice structures, policies, and practices, and the interactions they facilitate, are crucial for the sustainability of the workforce. Collaboration among GPs, the public, and national policymakers is essential for implementing the principles from this review. Future systems should enable personalised care; sustain meaningful work and relationships; facilitate meaning-making; and promote agency, agility, and flexibility to enable GPs to utilise, adapt, and cultivate expertise.
Genetic relationships and biobehavioral pathways between suicidality and comorbid mental disorders: a comprehensive cross-phenotype analysis
Authors: Huang Yunqi , Meng Ze , Tao Shiwan , Liu Yunjia , Miller-Matero Lisa R. , Iturralde Esti , Liang Xiaoyu , Levin Albert M. , Ahmedani Brian K. , Wang Qiang , Gui Hongsheng
Published: January 2025

Background

The close relationships between mental disorders and suicidality are frequently seen in epidemiology. Shared genetic liabilities and brain structure variation may underlie these associations. Therefore, we aimed to investigate the phenotypic and polygenetic associations between multiple mental disorders and different levels of suicidality, as well as mediation by grey morphology and white matter tracts.

Methods

Using raw data from the UK Biobank (UKB) European population, we first evaluated the phenotypic and polygenic relationships between 12 mental disorders and gradient scales of suicidality. We then accessed data from the All of Us (AoU) diverse cohort to replicate findings in European and African American populations. Demographic and social factors, including age, sex, BMI, education, deprivation, income, smoking, and chronic pain were included as covariates. Second, we used existing genome-wide association study (GWAS) summary statistics from 12 major mental conditions to estimate genetic correlations and identify pleiotropic genes using a combination of statistical genetics tools. Third, we further explored the potential mediation effects of brain structure on the relationship between mental disorders and suicidality through structural equation modeling and Mendelian randomization analyses.

Results

In the UKB European population, 150,861 eligible individuals were retained after standard GWAS quality control. Nine out of 12 mental disorders showed both significant phenotypic and polygenic correlations with gradient suicidality (Pbonferroni<0.05). Using GWAS summary statistics, we also observed positive global and regional genetic correlations between the 12 mental disorders and suicidality (rgranging from 0.25 to 0.68,Pbonferroni<0.05). Across pairs of suicidality and other mental disorders, we identified 73 out of 136 pleiotropic functional genes (including 58 novel ones associated with suicidality) shared by two or more pairs. These genes were enriched in pathways including regulation of immune system process and DNA, nucleosome and chromatin organization, and phenotypes as common mental disorders and brain morphology. Finally, the association between mental disorders and suicidality was significantly mediated by several structural brain imaging features.

Conclusion

This study underscores the urgent need to address the shared and distinct genetic architecture of suicidality and its related mental conditions. Combining longitudinal population-level biobanks with disease-ascertained GWAS data is warranted to further enhance our understanding of this complex phenomenon. Our research findings will guide future suicide prevention and precise treatment among individuals with or without major mental disorders.
Cortico-subcortical converging organization at rest
Authors: Dang Shilpa , Jallepalli Dheemant
Published: January 2025

Higher-order cognitive function relies on information convergence between functionally specialized communities. It is unknown how subcortex configures itself with respect to the local segregation and global integration dynamics at rest. Using functional MRI, we revealed three non-overlapping communities confined anatomically to thalamus, basal ganglia, and subcortical limbic structures and network hubs. Further, using statistical modelling we quantified the extent of convergence and found multiple, widespread cortical regions converging onto individual subcortical regions. We revealed a topographic organization of cortical convergence within subcortical resting state networks, such that thalamic, basal ganglia, subcortical limbic networks received convergence from cortical areas involved in sensorimotor integration, associative and motor control, limbic functions, respectively. Further, we found functional diversity of cortex to be the major driving factor behind cortical convergence within subcortex and that the absence of subcortical regions significantly impacted the information-transmission efficiency within the converging organization, underscoring the subcortical contributions to brain dynamics.
Subcortically generated movements activate motor cortex during sleep and wake in rats through postnatal day 24
Authors: Reid Madilyn R. , Dooley James C.
Published: January 2025

During early postnatal development, cortical motor control emerges from complex interactions between cortical and subcortical circuits. In primary motor cortex (M1), we know that this process depends on neural activity, but large gaps remain in our understanding of how M1 neural activity is patterned prior to the development of cortical motor control. To track the development of movement-related activity in M1 across sleep and wake, we performed acute, extracellular recordings of single-unit activity in the forelimb region of M1 of unanesthetized, head-fixed rats from postnatal day 12 (P12) to P24. At all ages, a subset of M1 neurons responded robustly and somatotopically to spontaneous limb twitches that occur during REM sleep. M1 neurons also showed robust responses to wake movements at these ages. From P12 to P24, the proportion of M1 neurons that showed twitch-related activity decreased, twitch-related activity became more temporally refined, and there was an increase in the proportion of activity that preceded movement onset. To compare M1’s developmentally nascent activity at P24 with that of an established motor structure, we performed simultaneous recordings in M1 and the red nucleus (RN). RN activity reliably preceded both twitches and wake movements, particularly compared to M1, reinforcing the conclusion that as late as P24 RN still predominantly drives limb movements. These results highlight M1’s protracted development and the continued importance of subcortically generated movements in driving activity that shapes M1’s circuitry, suggesting that movement-related activity during sleep and wake promotes the development of M1’s motor functions.
Identification and Engineering of UDP-rhamnosyltransferase fromTrillium tschonoskiifor Heterologous Biosynthesis of Polyphyllin II in Engineered Yeast
Authors: Yang Yuxin , Wang Haowen , Wu Ziya , Wang Xing , Tong Yuru , Huang Wei , Liu Xuan , Zhao Huan , Hu Yating , Zhang Xianan
Published: January 2025

Abstract

Polyphyllins, a class of isospirostan-type steroidal saponins, exhibit potent cytotoxicity against a variety range of cancer cells. Although extensive research efforts have been made, the complete biosynthetic pathway of these compounds remains unclear. In order to elucidate these pathways, different tissues from Trillium tschonoskii were collected for sequencing that yielded 173,382 high-quality unigene sequences, among which 353 were annotated as glycosyltransferases. Then, a novel rhamnosyltransferase gene, UGT738A3, was characterized, which catalyzes the conversion of triglycoside polyphyllin III and pennogenin 3-O-beta-chacotrioside into tetraglycoside polyphyllin II and polyphyllin VII. The key residues that affect the catalytic activity of UGT738A3 were identified through site-directed mutation that the mutant A158T/P101L exhibited improved catalytic activity towards polyphyllin III and pennogenin 3-O-beta-chacotrioside by 2.5-fold and 6.5-fold respectively. We thus reconstructed the biosynthesis pathway of polyphyllin II in yeast by introducing the UGT93M3(catalyzing the formation of polyphyllin VI) and UGT738A3A158T/P101L3. This study not only elucidates the pivotal role of UGT738A3 in catalyzing the formation of tetraglycoside, but also provides highly efficient enzymatic components essential for the heterologous biosynthesis of polyphyllin saponins.
Activity regulation of a glutamine amidotransferase bienzyme complex by substrate-induced subunit interface expansion
Authors: Funke Franziska Jasmin , Schlee Sandra , Bento Isabel , Bourenkov Gleb , Sterner Reinhard , Wilmanns Matthias
Published: January 2025

Glutamine amidotransferases are multienzyme machineries in which reactive ammonia is generated by a glutaminase and then transferred through a sequestered protein tunnel to a synthase active site for incorporation into diverse metabolites. To avoid wasteful metabolite consumption, there is a requirement for synchronized catalysis but any generally applicable mechanistic insight is still lacking. As synthase activity depends on glutamine turnover, we investigated possible mechanisms controlling glutaminase catalysis, using aminodeoxychorismate synthase involved in folate biosynthesis as a model. By analyzing this system in distinct states of catalysis, we found that incubation with glutamine leads to a subunit interface expansion by one third of its original area. These changes completely enclose the glutaminase active site for sequestered catalysis and subsequent transport of volatile ammonia to the synthase active site. In view of similar rearrangements in other glutamine amidotransferases, our observations provide a general mechanism for catalysis synchronization of this multienzyme family.
Distal mutations in a designed retro-aldolase alter loop dynamics to shift and accelerate the rate-limiting step
Authors: Hunt Serena E. , Klaus Cindy , John Aqza E. , Zarifi Niayesh , Martinez Alec , Feixas Ferran , Garcia-Borràs Marc , Thompson Michael C. , Chica Roberto A.
Published: January 2025

Amino-acid residues distant from an enzyme’s active site are known to influence catalysis, but their mechanistic contributions to the catalytic cycle remain poorly understood. Here, we investigate the structural, functional, and mechanistic impacts of distal and active-site mutations discovered through directed evolution of the computationally designed retro-aldolase RA95. Active-site mutations improve catalytic efficiency by 3,600-fold, while distal mutations alone offer no improvement. When combined with active-site mutations, distal mutations further increase efficiency by 6-fold, demonstrating an epistatic effect. X-ray crystallography and molecular dynamics simulations reveal that distal mutations promote active site opening by altering loop dynamics. Kinetic solvent viscosity effects and electrostatic analysis show that distal mutations accelerate the chemical transformation by 100-fold, shifting the rate-limiting step to product release, which is further accelerated by the increased opening of the active site. These findings highlight the critical role of distal residues in shaping the active-site environment and facilitating the structural dynamics essential for progression through the catalytic cycle.
Feedback regulation between FOXM1 and APC/CCdh1determines the changes in cell cycle dynamics during aging
Authors: Araújo Ana Rita , Gaspar-Silva Filipa , Logarinho Elsa
Published: January 2025

Aging is characterised by a loss of regenerative capacity, though it remains elusive how aged proliferating cells slowdown cycling eventually becoming senescent. We previously found that repression of the FOXM1 transcription factor accounts for mitotic decline during aging due to a global transcriptional shutdown of mitotic genes in proliferating cells. Intriguingly, a 1.5-fold increase in both cell cycle and mitosis durations was observed in elderly cells in deviancy to a previous study showing mitosis to be temporally insulated from variability in earlier cell cycle phases due to the robustness of the positive feedback loop controlling CDK1-Cyclin B1 activity. Thus, we asked if molecular thresholds controlling cell cycle phase transitions become unfitted with aging. Here, we used live-cell imaging of primary human dermal fibroblasts of advancing age donors in combination with high-throughput image analysis, to investigate age-related changes in cell cycle dynamics. Interestingly, we found mitosis insularity to be gradually lost along aging due to defective switch-like activation of CDK1 at mitotic entry driven byFOXM1repression. Moreover, we found the levels of FZR1/Cdh1 co-activator of APC/C, the E3-ubiquitin ligase directing the proteolytic degradation of FOXM1 at mitotic exit, to increase with advancing age. Importantly,FZR1/Cdh1repression was shown to restore cell cycle fitness and FOXM1 levels in aged proliferating cells, preventing the accumulation of cell cycle inhibitors and senescence markers in their progeny. Thus, changes in FOXM1 and APC/CCdh1interlinked activities account for the loss of proliferative capacity and senescence accrual during aging, thereby delivering useful markers and/or targets to explore in anti-aging approaches.
Combined Central and Peripheral Nerve Stimulation Improves Functional Recovery of Mixed Peripheral Nerve Injury in a Rat Forelimb Model
Authors: Eftekari Sahand C , Yoon Yong-Chul , Chen Rex Chin-Hao , Nicksic Peter J , Donnelly D'Andrea T , Jesch Anna , Shaffrey Ellen C , Zeng Weifeng , Ludwig Kip A , Poore Samuel O , Vakoc Benjamin J , Suminski Aaron , Dingle Aaron M
Published: January 2025

Introduction: Peripheral nerve reinnervation following nerve injury is often a slow and incomplete process, resulting in significant morbidity and permanent loss of function of the injured extremity in many patients. Prior studies have shown the efficacy of electrical stimulation to synchronize the axonal regeneration of both motor and sensory neurons in peripheral nerve injury models. Moreover, separate investigations have also shown the use of cranial nerve stimulation, principally the vagus nerve, to improve functional outcomes. However, no study has investigated the synergistic effects of both intraoperative electrical stimulation and cranial nerve stimulation for functional improvement within a peripheral nerve injury model. This investigation quantifies the efficacy of combined intraoperative electrical stimulation and trigeminal nerve stimulation on motor and sensory functional recovery in a rat peripheral nerve injury model. Methods: Twelve adult male Lewis rats were trained in a reach and pull task for a food reward using their right forelimb with baseline force thresholds and percent success of the pull task recorded. Baseline sensory data was retrieved using an automated von Frey monofilament test. All rats underwent surgical transection and 2mm gap repair of their median and ulnar nerve of their right forelimb followed by 1 hour of intraoperative electrical stimulation. Trigeminal nerve stimulation throughout the rehabilitation period was completed via supraorbital nerve headcap electrodes. Motor and sensory data were compared to historic cohorts comprised of sham surgery (no nerve injury), brief intraoperative electrical stimulation, trigeminal nerve stimulation, and a sham peripheral and trigeminal nerve stimulation group. Results: The combined cohort of rodents were able to recover to their pre-injury motor function by the third week of rehabilitation, faster than either of the singular electrical stimulation cohorts assessed previously. Moreover, functional sensory data of the combined stim cohort demonstrated no change when compared to their pre-injury baseline. Conclusions: Peripheral nerve electrical stimulation and trigeminal nerve stimulation are two separately acting mechanisms of therapy that employ electric waveforms to improve the functional recovery of injured peripheral nerves. The former acts within the periphery to synchronize axonal growth and regeneration of the injured neurons, while the latter acts centrally to augment neuroplasticity. When used simultaneously in a rodent peripheral nerve injury model, these modalities have shown to build upon each other to deliver a faster functional motor recovery, while sensory recovery outcomes remain to be demonstrated.
Cerebellar Purkinje cell stripe patterns reveal a differential vulnerability and resistance to cell loss during normal aging in mice
Authors: Donofrio Sarah G. , Brandenburg Cheryl , Brown Amanda M. , Lin Tao , Lu Hsiang-Chih , Sillitoe Roy V.
Published: January 2025

Age-related neurodegenerative diseases involve reduced cell numbers and impaired behavioral capacity. Neurodegeneration and behavioral deficits also occur during aging, and notably in the absence of disease. The cerebellum, which modulates movement and cognition, is susceptible to cell loss in both aging and disease. Here, we demonstrate that cerebellar Purkinje cell loss in aged mice is not spatially random but rather occurs in a pattern of parasagittal stripes. We also find that aged mice exhibit impaired motor coordination and more severe tremor compared to younger mice. However, the relationship between patterned Purkinje cell loss and motor dysfunction is not straightforward. Examination of postmortem samples of human cerebella from neurologically typical individuals supports the presence of selective loss of Purkinje cells during aging. These data reveal a spatiotemporal cellular substrate for aging in the cerebellum that may inform about how neuronal vulnerability leads to neurodegeneration and the ensuing deterioration of behavior.
Simultaneous, real-time tracking of many neuromodulatory signals with Multiplexed Optical Recording of Sensors on a micro-Endoscope
Authors: Kalugin Peter N. , Soden Paul A. , Massengill Crystian I. , Amsalem Oren , Porniece Marta , Guarino Diana C. , Tingley David , Zhang Stephen X. , Benson Jordan C. , Hammell Madalon F. , Tong David M. , Ausfahl Charlotte D. , Lacey Tiara E. , Courtney Ya’el , Hochstetler Alexandra , Lutas Andrew , Wang Huan , Geng Lan , Li Guochuan , Li Bohan , Li Yulong , Lehtinen Maria K. , Andermann Mark L.
Published: January 2025

Dozens of extracellular molecules jointly impact a given neuron, yet we lack methods to simultaneously record many such signals in real time. We developed a probe to track ten or more neuropeptides and neuromodulators using spatial multiplexing of genetically encoded fluorescent sensors. Cultured cells expressing one sensor at a time are immobilized at the front of a gradient refractive index (GRIN) lens for 3D two-photon imagingin vitroandin vivo.The sensor identity and detection sensitivity of each cell are determined via robotic dipping of the probe into wells containing various ligands and concentrations. Using this probe, we detected stimulation-evoked release of multiple neuromodulators in acute brain slices. We also tracked endogenous and drug-evoked changes in cerebrospinal fluid composition in the awake mouse lateral ventricle, which triggered downstream activation of the choroid plexus epithelium. Our approach offers a first step towards quantitative, real-time, high-dimensional tracking of brain fluid composition.
The biochemical function of bivalent aptamer assemblies against B-cell markers CD19 and CD20
Authors: Cen Yilam Ng , Williams Nicole B. , Di Siervi Nicolás , Chen Lexi , Seneviratne Pramodh , Kreitzer Geri , Cerchietti Leandro , Mallikaratchy Prabodhika
Published: January 2025

Aptamers are synthetic oligonucleotides that bind to their specific receptors with high specificity, offering immense potential for the development of molecular tools. Using recently introduced Ligand-Guided Selection (LIGS), a variant of the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) we previously identified anti-CD19 and anti-CD20 aptamers with specificity and affinity. Given their high expression levels, B-cell markers CD19 and CD20 are widely utilized in the diagnosis of B-cell-related malignancies and autoimmune diseases. Here, we report the design and functional characterization of bivalent aptamer assemblies targeting CD19 and CD20 expressed in B-cell lymphomas. Using a strategic approach, we synthesized dimeric constructs of these aptamers with polyethylene glycol (PEG) linkers of varying lengths to tether the two aptamer units. The bivalent aptamers demonstrated enhanced binding affinity and specificity, with an optimal linker length of ∼3.96 nm. Functional studies revealed that dimeric CD19 aptamers selectively internalized in CD21-negative B-cells, while CD20 aptamers exhibited improved antigen binding without triggering calcium release. These findings highlight the potential of bivalent aptamers in engineering cost-effective, stable, and precise therapeutic agents for B-cell-related malignancies, such as diffuse large B-cell lymphoma (DLBCL). This work advances the development of aptamer-based synthetic therapeutics with promising clinical applications.
Evolution and development of segmented body plan revealed byengrailedandwnt1gene expression in the annelidAlitta virens
Authors: Kairov Arsenii I. , Kozin Vitaly V.
Published: January 2025

Segmentation is one of the most striking features of bilaterians, and understanding its mechanisms provides insights into the evolution of body plans. In annelids, segmentation occurs at different developmental stages through a variety of processes, yet the molecular pathways remain underexplored. Aiming to compare segmentation patterns in ontogeny and phylogeny, we analysed the expression ofAvi-en(homologous toengrailed) andAvi-wnt1in the nereidid polychaeteAlitta virens. Using in situ hybridization, immunofluorescence, and cell proliferation assays, we mapped the spatiotemporal expression of these genes across embryonic, larval, and postlarval stages. We found thatAvi-enwas expressed in solid lateral domains early in the unsegmented protrochophore stage and progressed through a metameric pattern, whileAvi-wnt1expression appeared later, also aligning with segmental boundaries. At the nectochaete stage, the posterior domain ofAvi-enexpression in the growth zone expanded and splitted into two due to increased cell proliferation. The postlarval segment primordium then developed progressively, culminating in the activation ofAvi-wnt1at the posterior border. According to available published data, the revealed pattern of gradual segment formation is unique to nereidids. The observed divergence in gene expression and cell proliferation across annelids suggests that segmentation in bilaterians did not arise from a common ancestral mechanism. Our study enhances future progress in understanding the evolution of body patterning by providing a foundation for future comparisons.
A novel approach to tagging tubulin reveals MT assembly dynamics of the axoneme inTrypanosoma brucei
Authors: Abbühl Daniel , Pružincová Martina , Štěpánek Luděk , Bouscasse Eleonore , Azevedo Rita , Matondo Mariette , Varga Vladimir , Bonnefoy Serge , Bastin Philippe
Published: January 2025

The protozoan parasiteTrypanosoma bruceiis a mono-flagellated cell during the G1-phase of its cell cycle. In order to duplicate, it assembles a new flagellum alongside the mature one, in which further elongation is prevented. Our group proposed a model where the mature flagellum is locked after construction to full length (Bertiaux et al. 2018) and access of new building blocks for elongation is exclusive to the new flagellum. To test this hypothesis directly, we developed a tool for the inducible expression of tagged tubulin. Alpha-tubulin that was tagged with an intragenic Ty-1-epitope behaved indistinguishable from untagged tubulin. Its incorporation was monitored after inducible expression, to follow the assembly dynamics of microtubules in the cell body, the mitotic spindle and the flagellum. In this study we observed that integration of tubulin occurs at the distal flagellum tip at a linear rate and is indeed restricted to the new flagellum in bi-flagellated cells. This is direct evidence that trypanosomes avoid competition between the two flagella by allowing tubulin incorporation only in the new organelle. However, by tracing flagella over several cell cycles we could also show that mature flagella do not remain locked indefinitely. The restriction is lifted briefly after the bi-flagellated cell has divided and the daughter cell inheriting the old flagellum shows incorporation of newly synthesized building blocks again. It then has to lock again before the cell can assemble a new flagellum. Our findings suggest regular incorporation of tubulin at the tip of previously locked flagella. This evidence was supported with an orthogonal approach, with which we monitored the incorporation of HaloTag-tagged radial spoke protein 4/6. Since flagellum length in trypanosomes is stable, this indicates that the entire axoneme is subject to regular events of transient disassembly followed by assembly at its distal tip.
The role of cortico-thalamic feedback for visual information processing
Authors: Wei Wenqing , Rotter Stefan
Published: January 2025

In the early visual system, neurons in the dorsal lateral geniculate nucleus (dLGN) not only relay visual inputs from the retina to the primary visual cortex (V1), but also receive cortico-thalamic (CT) feedback inputs, which anatomically outnumber feedforward inputs. Most experimental and theoretical work so far has focused on the modulatory influence of CT feedback on relay cells in the dLGN. However, the role of feedback for the activity of V1 neurons, which are mainly driven by visual input meditated by dLGN neurons, is still unclear. To address this question, we devised a spiking neural network model of the thalamo-cortical and cortico-thalamic loop, where the CT feedback can be turned on and off to study its effect. We identified three main phenomena of the effect of CT feedback on V1 neurons: (i) orientation selectivity of cortical responses is increased for all contrasts, (ii) preferred orientations of input and output are better aligned with each other, (iii) neuronal population activity represents the stimulus orientation with higher confidence. Our analysis showed that CT feedback generally improves the signal-to-noise ratio (SNR) of the responses of dLGN neurons and therefore also increases the SNR of thalamic inputs to V1 neurons. Moreover, we found that the modulatory effects on visual processing depend on the geometry of the CT feedback projections. We conclude that CT feedback increases the selectivity of V1 neurons particularly at low contrasts by modulating the activity of dLGN neurons.

Author summary

Extensive experimental and theoretical studies have been conducted to understand the functional role of cortico-thalamic (CT) feedback on relay cells in the dorsal lateral geniculate nucleus (dLGN) during visual processing. However, it remains unclear how CT feedback affects the neuronal responses of V1 neurons. To address this question, we developed a computational model of the thalamo-cortico-thalamic loop circuit based on biophysical parameters. Our results indicate that CT feedback modulates the orientation preference of V1 neurons in a contrast-dependent manner: The increase of orientation selectivity (OS) is stronger and the input preferred orientation (PO) is better preserved at lower contrasts. Our analysis suggests a mechanistic explanation: The CT feedback attenuates the untuned part of the thalamic input, while it amplifies the tuned part. This effectively increases the signal-to-noise ratio (SNR) in particular for weak contrasts. Our network model for the first time allows us to study the effect of feedback on cortical neurons and understand the impact of the number and the geometry of feedback connections.
Positive affect amplifies integration within episodic memories in the laboratory and the real world
Authors: Pratt Julia G. , Wemm Stephanie E. , Harris Bailey B. , Huang Yuye , Sinha Rajita , Goldfarb Elizabeth V.
Published: January 2025

Emotional events hold a privileged place in our memories, differing in accuracy and structure from memories for neutral experiences. Although much work has focused on the pronounced differences in memory for negative experiences, there is growing evidence that positive events may lead to more holistic, or integrated, memories. However, it is unclear whether these affect-driven changes in memory structure, which have been found in highly controlled laboratory environments, extend to real-world episodic memories. We ran experiments that assessed memory for experiences created in the laboratory (Experiment 1) and, using smartphones, memories for everyday experiences (Experiment 2). We complement these design innovations with a novel analysis approach to model memory accuracy and integration in both settings. Consistent with past findings, emotional events were subjectively remembered more strongly. These studies also revealed that features of more positive events were indeed more integrated within memory, both in the laboratory and the real world. These effects were specific to participants’ emotional responses to the events during encoding rather than general emotional states at the time of retrieval, and reflected a general increase in integration between multiple memory features. Together, these results demonstrate robust differences in memory for positive events, introduce a novel measure of memory integration, and highlight the importance of assessing the impact of emotion on memory beyond the laboratory.
High optical anisotropy of the
GaSb/GaxIn1−xAsySb1−y
interface
Authors: Rygała Michał , Ziembicki Jakub , Smołka Tristan , Bader Andreas , Knebl Georg , Pfenning Andreas , Ryczko Krzysztof , Hartmann Fabian , Scharoch Paweł , Sęk Grzegorz , Höfling Sven , Motyka Marcin
Published: January 2025

We present the investigation of optical transitions in an GaSb/GaInAsSb-based heterostructure through different experimental and numerical methods. The transitions had high-temperature stability, with them being observed in the 10–300 K temperature range. Four pronounced optical transitions are observed at low temperature with three of them being nonpolarized and one showing a degree of linear polarization higher than 60%. Time-resolved measurements of the transitions showed a complex carrier dynamics with several distinct processes related to the investigated interface. Using several numerical methods, we identified that the highly polarized transition originates from the first electron state in the GaInAsSb layer and a two-dimensional hole gas created within a triangular quantum well at the interface with the -type doped GaSb layer. The optical polarization of the signal originates in directional elongation of the atomic bonds enhanced by possible local composition fluctuations and the inheritance of these properties by the signal from the triangular quantum well. Such physical phenomena have the potential to be used as an internal polarizing filter in structures designed for midinfrared optoelectronics.

Published by the American Physical Society
2025
Percolation renormalization group analysis of confinement in
Z2
lattice gauge theories
Authors: Dünnweber Gesa , Linsel Simon M. , Bohrdt Annabelle , Grusdt Fabian
Published: January 2025

The analytical study of confinement in lattice gauge theories (LGTs) remains a difficult task to this day. Taking a geometric perspective on confinement, we develop a real-space renormalization group (RG) formalism for Z2 LGTs using percolation probability as a confinement order parameter. The RG flow we analyze is constituted by both the percolation probability and the coupling parameters. We consider a classical Z2 LGT in two dimensions, with matter and thermal fluctuations, and analytically derive the confinement phase diagram. We find good agreement with numerical and exact benchmark results and confirm that a finite matter density enforces confinement at T<∞ in the model we consider. Our RG scheme enables future analytical studies of Z2 LGTs with matter and quantum fluctuations and beyond.

Published by the American Physical Society
2025
Evolution of nodal line induced out-of-plane anomalous Hall effect in
Co3Sn2S2
Authors: He Bin , Yu Tianye , Pan Yu , Le Congcong , Chen Dong , Sun Yan , Felser Claudia
Published: January 2025

Weyl semimetals have attracted considerable research interest over the past decade, with a number of intriguing transport phenomena reported. Magnetic Weyl semimetals, which break time reversal symmetry, have been predicted and recently discovered. Co3Sn2S2 is a magnetic Weyl semimetal that exhibit a giant anomalous Hall effect (AHE) when the magnetic moments are aligned along the c axis. In this paper, we report the evolution of the AHE with an external magnetic field applied in the ab plane and current along the c axis, namely, the out-of-plane AHE of Co3Sn2S2. Density functional theory calculations predict a finite out-of-plane AHE when the spins are fully aligned in the ab plane. The evolution of the magnetic structure modifies the nodal line distribution and the Berry curvature, resulting in a weaker AHE with an amplitude of 200Scm−1 at the saturation field. To ensure the alignment of the magnetic field in the ab plane, a two-round scanning process was performed experimentally. After this, the out-of-plane AHE was measured at multiple temperatures. The observed AHE signals with applied fields of 1 and 2 T were in good agreement with theoretical predictions. These results suggest that engineering the anomalous Hall effect may be possible by designing the symmetry relation of the local Berry curvature.

Published by the American Physical Society
2025
String scattering and evolution of a Ryu-Takayanagi surface
Authors: Jiang Xin , Wu Houwen , Yang Haitang
Published: January 2025

In this paper, our aim is to illustrate that the process of open string scattering corresponds to the evolution of the entanglement wedge, where the scattering distance is identified as the entanglement wedge cross section. Moreover, open-closed string scattering, specifically the disk-disk interaction, works for the evolution of the reflected entanglement wedge, with the circumference of the waist cross section equating to the reflected entropy. It therefore provides evidence for the deep connections between the string world sheet and the Ryu-Takayanagi surface. This connection is not only a coincidence rooted in hyperbolic geometry; it also reflects an additional correspondence between two distinct theories: mutual information and the geometric Batalin-Vilkoviski master equation.

Published by the American Physical Society
2025
Opportunities for gas-phase science at short-wavelength free-electron lasers with undulator-based polarization control
Authors: Ilchen Markus , Allaria Enrico , Rebernik Ribič Primož , Nuhn Heinz-Dieter , Lutman Alberto , Schneidmiller Evgeny , Tischer Markus , Yurkov Mikail , Calvi Marco , Prat Eduard , Reiche Sven , Schmidt Thomas , Geloni Gianluca Aldo , Karabekyan Suren , Yan Jiawei , Serkez Svitozar , Gao Zhangfeng , Deng Bangjie , Feng Chao , Deng Haixiao , Helml Wolfram , Funke Lars , Larsson Mats , Zhaunerchyk Vitali , Meyer Michael , Mazza Tommaso , Jahnke Till , Dörner Reinhard , Calegari Francesca , Smirnova Olga , Vozzi Caterina , De Ninno Giovanni , Wätzel Jonas , Berakdar Jamal , Bari Sadia , Schwob Lucas , Rouxel Jérémy R. , Mukamel Shaul , Bartschat Klaus , Hamilton Kathryn , Argenti Luca , Douguet Nicolas , Novikovskiy Nikolay M. , Demekhin Philipp V. , Walter Peter
Published: January 2025

Free-electron lasers (FELs) are the world's most brilliant light sources with rapidly evolving technological capabilities in terms of ultrabright and ultrashort pulses over a large range of photon energies. Their revolutionary and innovative developments have opened new fields of science regarding nonlinear light-matter interaction, the investigation of ultrafast processes from specific observer sites, and approaches to imaging matter with atomic resolution. A core aspect of FEL science is the study of isolated and prototypical systems in the gas phase with the possibility of addressing well-defined electronic transitions or particular atomic sites in molecules. Notably for polarization-controlled short-wavelength FELs, the gas phase offers new avenues for investigations of nonlinear and ultrafast phenomena in spin-orientated systems, for decoding the function of the chiral building blocks of life as well as steering reactions and particle emission dynamics in otherwise inaccessible ways. This roadmap comprises descriptions of technological capabilities of facilities worldwide, innovative diagnostics and instrumentation, as well as recent scientific highlights, novel methodology, and mathematical modeling. The experimental and theoretical landscape of using polarization controllable FELs for dichroic light-matter interaction in the gas phase will be discussed and comprehensively outlined to stimulate and strengthen global collaborative efforts of all disciplines.

Published by the American Physical Society
2025
Correlation effects in magic-angle twisted bilayer graphene: An auxiliary-field quantum Monte Carlo study
Authors: Xiao Zhi-Yu , Zhang Shiwei
Published: January 2025

Magic-angle twisted bilayer graphene (MATBG) presents a fascinating platform for investigating the effects of electron interactions in topological flat bands. The Bistritzer-MacDonald (BM) model provides a simplified quantitative description of the flat bands. Introducing long-range Coulomb interactions leads to an interacting BM (IBM) Hamiltonian, a momentum-space continuum description which offers a very natural starting point for many-body studies of MATBG. Accurate and reliable many-body computations in the IBM model are challenging, however, and have been limited mostly to special fillings or smaller lattice sizes. We employ a state-of-the-art auxiliary-field quantum Monte Carlo (AFQMC) method to study the IBM model, which constrains the sign problem to enable accurate treatment of large system sizes. We determine ground-state properties and quantify errors compared to mean-field theory calculations. Our calculations identify correlated metal states and their competition with the insulating Kramers intervalley-coherent state at both half-filling and charge neutrality. Additionally, we investigate one- and three-quarter fillings, and examine the effect of many-body corrections beyond single Slater determinant solutions. We discuss the effect that details of the IBM Hamiltonian have on the results, including different forms of double-counting corrections, and the need to establish and precisely specify many-body Hamiltonians to allow more direct and quantitative comparisons with experiments in MATBG.

Published by the American Physical Society
2025
Quantum tug of war between randomness and symmetries on homogeneous spaces
Authors: Arvind Rahul , Bharti Kishor , Khoo Jun Yong , Koh Dax Enshan , Kong Jian Feng
Published: January 2025

We explore the interplay between symmetry and randomness in quantum information. Adopting a geometric approach, we consider states as H equivalent if related by a symmetry transformation characterized by the group H. We then introduce the Haar measure on the homogeneous space U/H, characterizing true randomness for H-equivalent systems. While this mathematical machinery is well studied by mathematicians, it has seen limited application in quantum information. Our work addresses this gap, providing an example of utilizing homogeneous spaces to characterize symmetry in quantum information. This is followed by a discussion of approximations of true randomness, commencing with t-wise independent approximations and defining t designs on U/H and H-equivalent states. Transitioning further, we explore pseudorandomness, defining pseudorandom unitaries and states within homogeneous spaces. Finally, as a practical demonstration of our findings, we study the expressibility of quantum machine learning in homogeneous spaces. Our work provides a fresh perspective on the relationship between randomness and symmetry in the quantum world.

Published by the American Physical Society
2025
Public opinions on social media: how to become a trustworthy leader in times of crisis
Authors: Pitono Andi , Fauzi Fadhli Zul
Published: January 2025

Purpose

The study compares public opinions toward several heads of state in times of crisis across countries, especially during the conflict between Russia and Ukraine. Although recent studies have primarily addressed public sentiment during the COVID-19 pandemic, critical international conflicts continue to impact economic and political dynamics that need warrant examination.

Design/methodology/approach

Using social media data, this study utilizes content and sentiment analysis to assess public perceptions of leaders’ actions and communication strategies.

Findings

Findings indicate that most leaders elicited predominantly negative sentiment, with only two leaders viewed favorably.

Originality/value

A notable contribution of this study is the identification of communication patterns as pivotal in shaping public trust; leaders who failed to articulate a clear shared vision faced heightened negative sentiment, as ineffective communication fostered public distrust and anxiety. Although principles of ethical political leadership were observed in some responses, this study underscores that ethical leadership alone is insufficient. Transparent and strategic communication, particularly during crises, emerges as essential to aligning public perception and fostering trust, highlighting its importance as a core component of effective leadership in international conflicts.
Divergent impacts of financial factors on Islamic vs conventional stock markets: insights from advanced countries using MM-QR
Authors: Sadat Irfana , Gormus Sakir
Published: January 2025

Purpose

This study aims to explore how financial factors affect both conventional and Islamic stock market indices of G7 countries from July 27, 2015, to February 29, 2024.

Design/methodology/approach

It examines local factors like CDS, exchange rates and bond yields, along with global ones such as USCDS, VIX, OVX and MSCI, using the innovative MM-QR method to identify any asymmetric effects on stock market returns during bull, bear and normal market phases.

Findings

The findings suggest that CDS has a more pronounced negative impact on the conventional index compared to the Islamic index. While 10-year bond yields generally have a positive influence on both indices, except during bullish phases in Islamic markets. Exchange rates tend to negatively correlate with stock returns in both markets, except for a specific quarter in conventional markets. USCDS has a positive relationship with both conventional and Islamic indexes. The MSCI World Index has a significant positive effect on both markets, while VIX negatively affects the conventional market but tends to be positive in Islamic markets during bear and normal market conditions. OVX indicates that adverse news from the global oil market negatively impacts both conventional and Islamic stock markets.

Originality/value

Previous research has overlooked the comparative analysis, focusing solely on either Islamic or conventional equities. Therefore, the study initiates by analyzing how changes in financial factors affect Islamic equity returns within the G7 nations, with a parallel investigation into whether these effects align with those observed in conventional equity markets.
Rainfall seasonality shapes belowground root trait dynamics in an Amazonian tropical rainforest: A test of the stress‐dominance hypothesis
Authors: Valverde‐Barrantes Oscar J. , Lugli Laynara F. , Fuchslueger Lucia , Hofhansl Florian , Martins Nathielly , Cordeiro Amanda L. , Schapp Karst , Anderson Kelly M. , Garcia Sabrina , Grandis Adriana , Miron Carol A. , Fleisher Katrin , Hoosbeek Marcel R. , Hartley Ian P. , Oblitas Mendoza Erick , Lapola David , Quesada Carlos A.
Published: January 2025

The stress‐dominance hypothesis (SDH) predicts that trait variation at the community level increases with the availability of limiting resources, driving spatial and temporal patterns in above‐ground plant functional trait expression. Here, we test the assumption that the SDH also applies to fine roots responding to spatial and temporal fluctuations in soil resource availability.

We monitored fine root mass and functional root traits associated with resource acquisition, that is specific root length (SRL), specific root tip abundance (SRTA) and branching index (BI), and traits related to stress tolerance, such as root diameter (RD) and tissue density (RTD) in a Central Amazonian tree community. To test for spatial differences in root traits, we separated the uppermost organic (O‐A horizon, 0–5 cm) and mineral soil (B horizon, 5–15 cm) layers, and for temporal fluctuations, we investigated the relationship of precipitation on community‐level root variation over a period of 27 months.

In accordance with the SDH, we found that fine roots in the O‐A horizon have on average 15% higher SRL, 23% higher BI, 32% higher SRTA and 15% lower RTD than those in the B horizon. Similarly, precipitation shifted the community over time to higher mean SRL, BI and SRTA (r = 0.92, 0.84 and 0.94, p < 0.0001 respectively), although trait shifts occurred in the trimester after the rainy season onset, revealing a time‐lag between rainfall patterns and community response. We also detected a positive increase in trait range for SRL and SRTA with lagged precipitation (r = 0.90 and 0.79, p < 0.0001). On the other hand, traits related to stress showed a weaker negative relationship with instantaneous precipitation (r = −0.7 and −0.57, p = 0.046 and p = 0.1 for RD and RTD, respectively).

Our results supported the SDH predictions that root systems will become more acquisitive in areas with more resources, and that the community will shift to more acquisitive but also broader trait dispersion as hydric stress decreases. We conclude that although higher resource availability may increase competition for acquisition, trait overdispersion seems to promote species coexistence. Our results highlight how dynamic root systems can be in response to environmental cues, cautioning the common practice of making conclusions about root traits adaptations to environmental gradients based on a single sampling observation.

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