bluuebunny/crossref_metadata_2025 huggingface dataset:
Continuous self-repair protects vimentin intermediate filaments from fragmentation
Authors: Tran Quang D. , Lenz Martin , Wioland Hugo , Jegou Antoine , Romet-Lemonne Guillaume , Leduc Cécile
Published: September 2024

Intermediate filaments are key regulators of cell mechanics. Vimentin, a type of intermediate filament expressed in mesenchymal cells and involved in migration, forms a dense network in the cytoplasm that is constantly remodeled through filament transport, elongation/shortening, and subunit exchange. While it is known that filament elongation involves end-to-end annealing, it is unclear how the reverse process of filament shortening by fragmentation occurs. Here, we use a combination ofin vitroreconstitution probed by fluorescence imaging and theoretical modeling to uncover the molecular mechanism involved in filament breakage. We first show that vimentin filaments are composed of two layers of subunits, half of which are exchangeable and half of which are immobile. We also show that the exchangeable subunits are tetramers. We further reveal a mechanism of continuous filament self-repair in which a soluble pool of vimentin tetramers in equilibrium with the filaments is essential to maintain filament integrity. Filaments break as a consequence of local fluctuations in the number of subunits per cross-section induced by the constant subunit exchange of tetramers. We determine that a filament tends to break if about four tetramers are removed from the same filament cross-section. Finally, we analyze the dynamics of association/dissociation and fragmentation to estimate the binding energy of a tetramer to a complete versus a partially disassembled filament. Our results provide a comprehensive description of vimentin turnover and reveal the link between subunit exchange and fragmentation.

SIGNIFICANCE STATEMENT

Intermediate filaments, including vimentin, are a key component of the cytoskeleton, which is essential for cell mechanics. Inside the cell, vimentin forms a dense network that is constantly remodeled to fulfill its functions. In particular, the filaments elongate and fragment, but the molecular mechanism involved in this breakage was unknown. Here we show that fragmentation is a consequence of the constant exchange of subunits along the filament length, which could locally weaken the filament. Our results provide a physical understanding of the mechanisms involved in regulating filament length, a feature that is essential for determining the dynamic organization of the network in both healthy and diseased cells in which intermediate filament assembly is disrupted.
Apusomonad photophobic behavior highlights cytoskeletal responses to blue light in early eukaryotes
Authors: Shibata Aika , Yamamoto Chiaki , Yanase Ryuji , Shiba Kogiku , Sato Yu , Yabuki Akinori , Inaba Kazuo
Published: September 2024

Light response is a fundamental characteristic of eukaryotic organisms, both unicellular and multicellular. However, no photoresponse has previously been reported in Apusomonadida, a group of small, free-living biflagellates phylogenetically positioned as a sister group to Opisthokonta (animals, fungi, and their unicellular relatives). Apusomonads are thus crucial for understanding the evolution of opisthokonts. Here, we report for the first time an avoidance response to blue light in the apusomonadPodomonas kaiyoae. This avoidance response is accompanied by an increase in gliding velocity, transient changes in flagellar waveforms, and alterations in cell shape. Dynamic cell contraction is induced by an increase in intracellular free Ca2+ and is inhibited by either a dynein inhibitor or an actin-disrupting drug. These findings suggest that the photophobic behavior ofPodomonas kaiyoaerelies on cytoskeletal responses mediated by both the dynein/tubulin and myosin/actin systems, which were acquired early in eukaryotic evolution. The dominance of the posterior flagellum in cilia-driven directional changes further supports the phylogenetic placement of apusomonads as a sister group to opisthokonts rather than other eukaryotic lineages.
Bumblebees locate goals in 3D with absolute height estimation from ventral optic flow
Authors: Sonntag Annkathrin , Egelhaaf Martin , Bertrand Olivier J. N. , Lihoreau Mathieu
Published: September 2024

Introduction

When foraging, flying animals like bees are often required to change their flight altitude from close to the ground to above the height of the vegetation to reach their nest or a food source. While the mechanisms of navigating towards a goal in two dimensions are well understood, the explicit use of height as a source for navigation in three dimensions remains mostly unknown. Our study aims to unravel which strategies bumblebees use for height estimation and whether they rely on global or local cues.

Methods

We expanded a 2D goal localization paradigm, where a goal location is indicated by cylindrical landmarks, to the third dimension by using spherical landmarks to indicate a feeder’s position in 3D and examined the search pattern of bumblebees. Additionally, we assessed the ability of bees to estimate the height of a feeder based on local landmarks and global references such as the ground floor.

Results

The search distribution for a feeder’s position in 3D was less spatially concentrated compared to in 2D. Assessing the bees’ height estimation ability, we found that bees could estimate a feeder’s height using the ground floor as a reference. However, the feeder needed to be sufficiently close to the ground floor for the bees to choose correctly.

Discussion

When bumblebees are faced with the challenge of foraging in a 3D environment where the height of a food source and landmark cues are important, they demonstrate the ability to learn and return to a specific flower height. This suggests they rely on ventral optic flow for goal height estimation in bumblebees.
Water-saving GC-MC model captures temporally differential enzymatic and transporter activities during C3-CAM transition
Authors: Sarkar Devlina , Kundu Sudip
Published: September 2024

CAM (Crassulacean Acid Metabolism) plants reduce the water loss through transpiration in arid environments (Wickell et al., 2021), using an alternative pathway of carbon assimilation. To ensure food security, engineering CAM into C3plants can be achieved by inverting the stomatal rhythm and the timing of major CO2uptake from day to night. Identification of the metabolic enzymes and intra-cellular transporters, present in both C3and CAM but having different differential temporal activities throughout the diel cycle (Yang et al., 2015; Heyduk et al., 2019) and quantitative estimations of the flux distributions along the biochemical trajectory of C3-to-CAM transition may help us to achieve the goal. Here, we simulate a constraint-based combined metabolic model of guard cell (GC) and mesophyll cell (MC), linking temporal fluctuations of temperature (T) and relative humidity (RH) throughout the diurnal cycle with osmolyte accumulation dependent stomatal opening, CO2uptake and transpirational water loss. Starting with C3metabolism, gradual increase in water-use efficiency (WUE) captures several known and new differential activities of metabolic enzymes, transporters, sugar-malate cycle etc. in GC and MC during C3-to-CAM transition.
Mapping Contributions of the Anterior Temporal Semantic Hub to the Processing of Abstract and Concrete Verbs
Authors: Muraki Emiko J. , Pexman Penny M. , Binney Richard J.
Published: September 2024

Multiple representation theories of semantic processing propose that word meaning is supported by simulated sensorimotor experience in modality-specific neural regions, as well as in cognitive systems that involve processing of linguistic, emotional, and introspective information. According to the Hub and Spoke Model of Semantic Memory, activity from these distributed cortical areas feeds into a primary semantic hub located in the ventral anterior temporal lobe (vATL). Though a substantial amount of research has tested this model in terms of concrete noun representation, there is less known about how this model can account for the representation of verb meaning, and in particular the meaning of abstract verbs which convey important information, for example, about socioemotional dynamics. In the present pre-registered study, we examined whether different types of abstract verbs (mental, emotional, nonembodied) and concrete (embodied) verbs all engage the vATL, and also whether they differentially recruit a broader set of distributed neurocognitive systems (consistent with multiple representation theories). Finally, we investigated whether there is information about different verb types distributed across the broader ATL region, consistent with a Graded Semantic Hub Hypothesis. We collected data from 30 participants who completed a syntactic classification task (is it a verb? Yes or no) and a numerical judgement task which served as an active but less semantic baseline task. Whole brain univariate analyses revealed consistent BOLD signal throughout the canonical semantic network, including the left inferior frontal gyrus, left middle temporal gyrus, and the vATL. All types of abstract verbs engaged the vATL except for mental state verbs. Finally, a multivariate pattern analysis revealed clusters within the ATL that were differentially engaged when processing each type of abstract verb. Our findings extend previous research and suggest that the hub-and-spoke hypothesis and the graded semantic hub hypothesis provide a neurobiologically constrained model of semantics that can account for abstract verb representation and processing.
CAR-T cells targeting CCR9 and CD1a for the treatment of T cell acute lymphoblastic leukemia
Authors: Tirado Néstor , Mansilla María José , Martínez-Moreno Alba , Alcain Juan , García-Peydró Marina , Roca-Ho Heleia , Fernandez-Fuentes Narcis , Garcia-Perez Alba , Guerrero-Murillo Mercedes , Falgàs Aïda , Velasco-Hernandez Talia , Vinyoles Meritxell , Bueno Clara , Engel Pablo , González E Azucena , Vick Binje , Jeremias Irmela , Caye-Eude Aurélie , Baruchel André , Cavé Hélène , Genescà Eulàlia , Ribera Jordi , Díaz-Beyá Marina , Ramírez-Orellana Manuel , Torrebadell Montserrat , Díaz Víctor M , Toribio María L , Sánchez-Martínez Diego , Menéndez Pablo
Published: September 2024

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy characterized by high rates of induction failure and relapse, and effective targeted immunotherapies are lacking. Despite promising clinical progress with genome-edited CD7-directed CAR-T cells, which present significant logistical and regulatory issues, CAR-T cell therapy in T-ALL remains challenging due to the shared antigen expression between malignant and healthy T cells. This can result in CAR-T cell fratricide, T cell aplasia, and the potential for blast contamination during CAR-T cell manufacturing. Recently, CAR-T cells have been described that target non-pan-T antigens, absent on healthy T cells but expressed on specific T-ALL subsets. These antigens include CD1a (NCT05679895), which is expressed in cortical T-ALL, and CCR9. We show that CCR9 is expressed on >70% of T-ALL patients (132/180) and is maintained at relapse, with a safe expression profile in healthy hematopoietic and non-hematopoietic tissues. Further analyses showed that dual targeting of CCR9 and CD1a could benefit ∼86% of patients with T-ALL, with a greater blast coverage than single CAR-T cell treatments. We therefore developed, characterized, and preclinically validated a novel humanized CCR9-specific CAR with robust and specific antileukemic activity as a monotherapyin vitroandin vivoagainst cell lines, primary T-ALL samples, and patient-derived xenografts. Importantly, CCR9/CD1a dual-targeting CAR-T cells showed higher efficacy than single-targeting CAR-T cells, particularly in T-ALL cases with phenotypically heterogeneous leukemic populations. Dual CCR9/CD1a CAR-T therapy may prevent T cell aplasia and obviate the need for allogeneic transplantation and regulatory-challenging genome engineering approaches in T-ALL.
Does transcutaneous vagus nerve stimulation alter pupil dilation? A living Bayesian meta-analysis
Authors: Pervaz Ipek , Thurn Lilly , Vezzani Cecilia , Kaluza Luisa , Kühnel Anne , Kroemer Nils B.
Published: September 2024

Transcutaneous vagus nerve stimulation (tVNS) has emerged as a promising technique to modulate autonomic functions, and pupil dilation has been recognized as a promising biomarker for tVNS-induced monoaminergic release. Nevertheless, studies on the effectiveness of various tVNS protocols have produced heterogeneous results on pupil dilatation to date. Here, we synthesize the existing evidence and compare conventional continuous and pulsed stimulation protocols using Bayesian meta-analysis. To maintain a living version, we developed a Shiny App with the possibility to incorporate newly published studies in the future. Based on a systematic review, we included 18 studies (N = 771) applying either continuous or pulsed stimulation protocols. Across studies, we found anecdotal evidence for the alternative hypothesis that tVNS increases pupil size (g= 0.14, 95% CI = [0.001, 0.29], BF01 = 2.5). Separating studies according to continuous vs. pulsed protocols revealed that results were driven by studies using pulsed taVNS (strong evidence for the alternative hypothesis:g= 0.34, 95% CI = [0.15, 0.53], BF10 = 14.15) while continuous tVNS provided strong evidence for the null hypothesis (g= 0.01, CI = [-0.15, 0.16], BF01= 20.7). In conclusion, our meta-analysis highlights differential effects of continuous and pulsed tVNS protocols on pupil dilation. These findings underscore the relevance of tVNS protocols in optimizing its use for specific applications that may require modulation of tonic vs. phasic monoaminergic responses.
Long-term Tolerance to Islet Transplantation via Targeted Reduction of beta cell-specific T cells
Authors: Kotliar Michael , Cianciolo Eileen E. , Pham Duc Hung , Carroll Kaitlin R. , Barski Artem , Jordan Michael B. , Katz Jonathan D.
Published: September 2024

Type 1 diabetes (T1D) results from insulin insufficiency due to the loss or dysfunction of pancreatic beta cells following T cell-mediated autoimmune attack. Currently the only long-term therapy is daily exogenous insulin replacement. The ideal curative approach is the durable restoration of functional islets via transplantation. To date the limiting factors impeding realization of this goal is the lack of a cost effective and limitless source of high-quality islets suitable for transplantation and the ability to provide long-term islet graft acceptance without prolonged need for deleterious immunosuppression. Ongoing clinical trials are testing islets derived from human induced pluripotent stem cells (iPSC); however, long-term acceptance of islet graft will require a effective therapeutic strategy to prevent engrafted islet destruction by pre-existing islet-antigen specific T cells. Here we demonstrate in the NOD mouse model for T1D that autologous islet graft acceptance can be achieved by the targeted elimination of (re)-activated islet-reactive CD4+and CD8+T effector (Teff) cells in the initial post-transplantation period by using a short-acting, combination therapy that results in the elimination of islet-reactive Teff cells by exacerbation of their natural DNA damage response (DDR) to drive apoptosis while at the same time maintaining endogenous Treg cells.

Article Highlights

Activated beta-cell reactive CD4+and CD8+T effector cells undergo a profound DNA-damage response which is targetable by small molecule inhibitors of the p53 and cell cycle pathways that lead to apoptosis.

The use of a combination of MDM2 and WEE1 inhibitors, which termed “p53 potentiation with checkpoint abrogation” (PPCA), conferred significant therapeutic efficacy in treating mouse models of new onset T1D.

Specific targeting of these T effector cells by PPCA results in a loss of inflammatory T cell subsets, notably proliferation CD4+Th0 and Th1 subsets and CD8+T effector memory cells, as determined by single cell RNA-seq studies with the preservation of T regulatory cells.

When autologous islet grafts are given to established diabetic NOD mice, a single course of PPCA results in long-term islet graft acceptance, restoration of normoglycemia and loss of beta cell specific CD4+and CD8+T cells.

PPCA shows promise as a potential means of estimating islet graft tolerance in T1D recipients of islet graft transplantation.
A gut-brain-gut interoceptive circuit loop gates sugar ingestion in Drosophila
Authors: Cui Xinyue , Meiselman Matthew R. , Thornton Staci N. , Yapici Nilay
Published: September 2024

The communication between the brain and digestive tract is critical for optimising nutrient preference and food intake, yet the underlying neural mechanisms remain poorly understood1-7. Here, we show that a gut-brain-gut circuit loop gates sugar ingestion in flies. We discovered that brain neurons regulating food ingestion, IN18, receive excitatory input from enteric sensory neurons, which innervate the oesophagus and express the sugar receptor Gr43a. These enteric sensory neurons monitor the sugar content of food within the oesophagus during ingestion and send positive feedback signals to IN1s, stimulating the consumption of high-sugar foods. Connectome analyses reveal that IN1s form a core ingestion circuit. This interoceptive circuit receives synaptic input from enteric afferents and provides synaptic output to enteric motor neurons, which modulate the activity of muscles at the entry segments of the crop, a stomach-like food storage organ. While IN1s are persistently activated upon ingestion of sugar-rich foods, enteric motor neurons are continuously inhibited, causing the crop muscles to relax and enabling flies to consume large volumes of sugar. Our findings reveal a key interoceptive mechanism that underlies the rapid sensory monitoring and motor control of sugar ingestion within the digestive tract, optimising the diet of flies across varying metabolic states.
Architecture of the ATP-driven motor for protein import into chloroplasts
Authors: Wang Ning , Xing Jiale , Su Xiaodong , Pan Junting , Chen Hui , Shi Lifang , Si Long , Yang Wenqiang , Li Mei
Published: September 2024

Thousands of nuclear-encoded proteins are transported into chloroplasts through the TOC-TIC translocon spanning the chloroplast envelope membranes. A motor complex pulls the translocated proteins out of the TOC-TIC complex into the chloroplast stroma by hydrolyzing ATP. The Orf2971-FtsHi complex was suggested to serve as the ATP-hydrolyzing motor inChlamydomonas reinhardtii, but little is known about its architecture and assembly. Here, we report the 3.2-Å resolution structure of theChlamydomonasOrf2971-FtsHi complex. The 20-subunit complex spans the chloroplast inner envelope with two bulky modules protruding into the intermembrane space and stromal matrix. Six subunits form a hetero-hexamer potentially providing the pulling force through ATP hydrolysis. The remaining subunits, including potential enzymes/chaperones, likely facilitate the complex assembly and regulate its proper function. Our results provide the structural foundation for mechanistic understanding of chloroplast protein translocation.
Motor decision-making under uncertainty and time pressure
Authors: Contemori Samuele , Carroll Timothy
Published: September 2024

Purposeful movement often requires selection of a particular action from a range of alternatives, but how does the brain represent potential actions so that they can be compared for selection, and how are motor commands generated if movement is initiated before the final goal is identified? According to one hypothesis, the brain averages partially prepared motor plans to generate movement when there is goal uncertainty. This is consistent with the idea that motor decision making unfolds through competition between internal representations of alternative actions. An alternative hypothesis holds that only one movement, which is optimised for task performance, is prepared for execution at any time. Under this conception, decisions about the best motor goal given current information are completed upstream from neural circuits that perform motor planning. To distinguish between these hypotheses, we modified Alhussein and Smith (2021) experiment in which participants had to start reaching toward targets associated with opposite curl force-fields prior to knowing the correct target to reach. Crucially, we forced the participants to initiate movement immediately after target presentation (i.e. mean reaction times ~250ms) so that they had limited opportunity to deliberate between the available alternatives. We found that the reaching dynamics reflected only those learnt for the selected reach direction, rather than a combination of those for the alternative targets presented, irrespective of the time available to initiate movement. The data are consistent with the conclusion that reaching dynamics were specified downstream of action selection under the target uncertainty conditions of this study.
Conserved variation across scales unveils dialectical relationships of micro- and macroevolution
Authors: Saito Keita , Tsuboi Masahito , Takahashi Yuma
Published: September 2024

Variation enables short-term evolution (microevolution), but its role in long-term evolution (macroevolution) is debated. Here, we analyzed a dataset ofDrosophilawing variation across six levels of biological organization to demonstrate that microevolutionary variation and macroevolutionary divergence are positively correlated at all levels from variation within an individual to 40 million years of macroevolution. Surprisingly, the strongest relationship was between developmental noise and macroevolutionary divergence—levels thought to be the most distant—whereas the relationship between standing genetic variation and population divergence was modest, despite established theoretical predictions. Our results indicate that the congruence of developmental system with long-term history of fluctuation in adaptive peaks creates dialectical relationships between microevolution and macroevolution.
Constructing a Draft Indian Cattle Pangenome Using Short-Read Sequencing
Authors: Azam Sarwar , Sahu Abhisek , Pandey Naveen Kumar , Neupane Mahesh , Van Tassell Curtis P , Rosen Benjamin D , Gandham Ravi Kumar , Rath Subha Narayan , Majumdar Subeer S
Published: September 2024

Background

Indian cattle known asdesicattle, renowned for their adaptability to harsh environments and diverse phenotypic traits, represent a valuable genetic resource. While reference genome assemblies have been instrumental in advancing cattle genomics, they often fail to capture the full spectrum of genetic variation present within diverse populations. To address this limitation, we aimed to construct a pangenome fordesicattle by identifying and characterizing Non-Reference Novel Sequences (NRNS).

Findings

We sequenced 68desicattle genomes representing seven distinct breeds, generating 48.35 billion short reads. A PanGenome Analysis (PanGA) pipeline was developed in Bash scripts to process these data to identify NRNS missing in the reference genome. A total of 13,065 NRNS with a cumulative length of ∼41 Mbp were identified that exhibited substantial variation across the population. These NRNS were found to be exclusive to Indiandesicattle, matching only 4.1% with the Chinese indicine pangenome. However, a significant proportion (∼40%) of NRNS displayed ancestral origins within the Bos genus. These sequences were enriched in genic regions, suggesting functional roles, and were associated with quantitative trait loci (QTLs), particularly for milk production. Compared to a single reference genome, the pangenome approach significantly enhanced read mapping accuracy, reduced spurious SNP calls, and facilitated the discovery of novel genetic variants.

Conclusions

This study has successfully established a within-species cattle pangenome specifically focused ondesicattle breeds from India. Our findings highlight the importance of pangenome based analyses for understanding the complex genetic architecture ofdesicattle.
Histone serves as an eat-me signal to induce RAGE-mediated phagocytosis
Authors: Li Yuqing , Zhou Xiaoman , Yang Yan , Du Congcong , Liu Yi-shi , Li Zijie , Nakanishi Hideki
Published: September 2024

The receptor for advanced glycation end products (RAGE) is a multiligand receptor that can induce phagocytosis in both professional and nonprofessional phagocytes. We found that histones are another ligand for RAGE. Binding between histones and RAGE is increased when DNA is attached to histones. While histones are chromosomal proteins in healthy cells, they are exposed to the cell surface as a complex with DNA when cells undergo apoptosis. The phagocytosis of apoptotic cells by either professional or nonprofessional phagocytes is enhanced when histones are present on the surface of apoptotic cells. Thus, histones serve as eat-me signals. InRAGEknockout cells, the phagocytosis of apoptotic cells was not influenced by the removal of histones, indicating that RAGE is required for the removal of histones from histone-presenting cells. In RAGE knockout mice, wound healing and removal of apoptotic cells from wound sites are delayed, suggesting that RAGE-mediated phagocytosis functions under physiological conditions.
Neural population dynamics during sleep in a songbird vocal circuit resemble sharp wave ripple activity
Authors: Lorenz Corinna , Das Anindita , Centeno Eduarda Gervini Zampieri , Yeganegi Hamed , Duvoisin Robin , Ursu Roman , Retailleau Aude , Giret Nicolas , Leblois Arthur , Hahnloser Richard H. R. , Ondracek Janie M.
Published: September 2024

During vocal learning, juvenile songbirds use auditory feedback and trial-and-error motor learning to transition from acoustically simple, highly variable songs to complex and stereotypical adult songs. Similar to motor skill learning in mammals, vocal learning in songbirds requires a set of interconnected brain areas that make up an analogous basal ganglia-thalamocortical circuit known as the anterior forebrain pathway (AFP). Although neural activity in the AFP has been extensively investigated during awake singing, very little is known about its neural activity patterns during offline sleep periods.

In this work, we used chronically implanted Neuropixels probes to investigate neural activity in the AFP during offline periods of natural sleep. We found that neurons in the pallial region LMAN (lateral magnocellular nucleus of the nidopallium) transitioned from sparse synchronous firing to asynchronous firing during sleep, which corresponded to slow wave sleep (SWS) and rapid eye movement (REM) sleep, respectively. SWS periods were associated with increased spiking variability for LMAN neurons, but not for neurons in the striatal region Area X (proper name). Coinciding with the increased spiking variability, we observed that populations of LMAN neurons were co-activated at specific time points during sleep in bursting events that were characterized by a negative deflection in the local field potential (LFP) and a transient increase in gamma power. Overall, the LMAN population bursting events were highly reminiscent of sharp-wave ripple (SWR) activity observed in rodent hippocampus.

Contrary to our expectations, we did not observe strong cross-area field coherence between LMAN and Area X, although individual LMAN-Area X LFP pairs did show coherence > 0.5. These results provide the first description of cross-area dynamics within the AFP during sleep. Furthermore, the observation of SWR-like events during sleep in LMAN suggests that large-scale population events have diverse functions across vertebrates.
Novel Role of Endothelial CD45 in Regulating Endothelial-to-Mesenchymal Transition in Atherosclerosis
Authors: Peng Qianman , Arulsamy Kulandaisamy , Lu Yao Wei , Wu Hao , Zhu Bo , Singh Bandana , Cui Kui , Wylie-Sears Jill , Li Kathryn , Wong Scott , Cowan Douglas B. , Aikawa Masanori , Wang Da-Zhi , Bischoff Joyce , Chen Kaifu , Chen Hong
Published: September 2024

Background

Protein-tyrosine-phosphatase CD45 is exclusively expressed in all nucleated cells of the hematopoietic system but is rarely expressed in endothelial cells. Interestingly, our recent study indicated that activation of the endogenous CD45 promoter in human endothelial colony forming cells (ECFCs) induced expression of multiple EndoMT marker genes. However, the detailed molecular mechanisms underlying CD45 that drive EndoMT and the therapeutic potential of manipulation of CD45 expression in atherosclerosis are entirely unknown.

Method

We generated a tamoxifen-inducible EC-specific CD45 deficient mouse strain (EC-iCD45KO) in an ApoE-deficient (ApoE-/-) background and fed with a Western diet (C57BL/6) for atherosclerosis and molecular analyses. We isolated and enriched mouse aortic endothelial cells with CD31 beads to perform single-cell RNA sequencing. Biomedical, cellular, and molecular approaches were utilized to investigate the role of endothelial CD45-specific deletion in the prevention of EndoMT in ApoE-/-model of atherosclerosis.

Results

Single-cell RNA sequencing revealed that loss of endothelial CD45 inhibits EndoMT marker expression and transforming growth factor-β signaling in atherosclerotic mice. which is associated with the reductions of lesions in the ApoE-/-mouse model. Mechanistically, the loss of endothelial cell CD45 results in increased KLF2 expression, which inhibits transforming growth factor-β signaling and EndoMT. Consistently, endothelial CD45 deficient mice showed reduced lesion development, plaque macrophages, and expression of cell adhesion molecules when compared to ApoE-/-controls.

Conclusions

These findings demonstrate that the loss of endothelial CD45 protects against EndoMT-driven atherosclerosis, promoting KLF2 expression while inhibiting TGFβ signaling and EndoMT markers. Thus, targeting endothelial CD45 may be a novel therapeutic strategy for EndoMT and atherosclerosis.
Linear response theory for light dark matter-electron scattering in materials
Authors: Catena Riccardo , Spaldin Nicola A.
Published: September 2024

We combine the nonrelativistic effective theory of dark matter (DM)-electron interactions with linear response theory to obtain a formalism that fully accounts for screening and collective excitations in DM-induced electronic transition rate calculations for general DM-electron interactions. In the same way that the response of a dielectric material to an external electric field in electrodynamics is described by the dielectric function, so in our formalism the response of a detector material to a DM perturbation is described by a set of which can be directly related to densities and currents arising from the nonrelativistic expansion of the Dirac Hamiltonian. We apply our formalism to assess the sensitivity of non-spin-polarized detectors, and find that in-medium effects significantly affect the experimental sensitivity if DM couples to the detector's electron density, while being decoupled from other densities and currents. Our formalism can be straightforwardly extended to the case of spin-polarized materials.

Published by the American Physical Society
2024
Non-Markovian collective emission of giant emitters in the Zeno regime
Authors: Qiu Qing-Yang , Lü Xin-You
Published: September 2024

We explore the collective Zeno dynamics of giant artificial atoms that are coupled, via multiple coupling points, to a common photonic or acoustic reservoir. In this regime, the establishment of atomic cooperativity and the revivification of exponential decay are highly intertwined, which is utterly beyond the non-Markovian regime with only retarded backaction. We reveal that giant atoms build up their collective emission smoothly from the decay rate of zero to that predicted by Markovian approximation and show great disparity between different waveguide QED setups. As a comparison, the steplike growth of instantaneous decay rates in the retardation-only picture has also been shown. All of these theoretical pictures predict the same collective behavior in the long time limit. From a phenomenological standpoint, we observe that the atomic superradiance exhibits significant directional property. In addition, the subradiant photons feature prolonged oscillation in the early stage of collective radiance, where the energy is exchanged remarkably between giant emitters and the field. Our results might be probed in state-of-art waveguide QED experiments and fundamentally broaden the fields of collective emission in systems with giant atoms.

Published by the American Physical Society
2024
Observation of Pairwise Level Degeneracies and the Quantum Regime of the Arrhenius Law in a Double-Well Parametric Oscillator
Authors: Frattini Nicholas E. , Cortiñas Rodrigo G. , Venkatraman Jayameenakshi , Xiao Xu , Su Qile , Lei Chan U. , Chapman Benjamin J. , Joshi Vidul R. , Girvin S. M. , Schoelkopf Robert J. , Puri Shruti , Devoret Michel H.
Published: September 2024

By applying a microwave drive to a specially designed Josephson circuit, we have realized a double-well model system: a Kerr oscillator submitted to a squeezing force. We have observed, for the first time, the spectroscopic fingerprint of a quantum double-well Hamiltonian when its barrier height is increased: a pairwise level kissing (coalescence) corresponding to the exponential reduction of tunnel splitting in the excited states as they sink under the barrier. The discrete levels in the wells also manifest themselves in the activation time across the barrier which, instead of increasing smoothly as a function of the barrier height, presents steps each time a pair of excited states is captured by the wells. This experiment illustrates the quantum regime of Arrhenius’s law, whose observation is made possible here by the unprecedented combination of low dissipation, time-resolved state control, 98.5% quantum nondemolition single shot measurement fidelity, and complete microwave control over all Hamiltonian parameters in the quantum regime. Direct applications to quantum computation and simulation are discussed.

Published by the American Physical Society
2024
Crystal structures and properties of derivatives of the alkaloid matrine: salts and hydrate forms
Authors: Liu Jiyong , Shi Dier , Yu Kaxi , Liu Shuna , Chen Linshen , Hu Xiurong
Published: September 2024

We report the crystal structures of three matrine derivatives, namely, the salts (1R,2R,9S,17S)-6-oxo-7,13-diazatetracyclo[7.7.1.02,7.013,17]heptadecan-13-ium (2E)-3-(3,4-dihydroxyphenyl)prop-2-enoate (matrine caffeinate) sesquihydrate, C15H25N2O+·C9H7O4
−·1.5H2O (Matrine–CA), and the 2-hydroxybenzoate (salicylate) monohydrate, C15H25N2O+·C7H5O3
−·H2O (Matrine–SA), as well as the 1.75-hydrate form, (1R,2R,9S,17S)-7,13-diazatetracyclo[7.7.1.02,7.013,17]heptadecan-6-one 1.75-hydrate, C15H24N2O·1.75H2O (Matrine–H). Each derivative exhibited a consistent molecular conformation for the matrine core, which is notably distinct from that of the anhydrous form. Notably, both salts crystallized in the orthorhombic space group P212121, with an asymmetric unit featuring one cation and one anion. Within the two salt structures, intermolecular proton transfer between matrine and the acid is observed, culminating in the formation of a matrine cation protonated at the tertiary amine N site. The Matrine–CA crystal packing is manifested as a three-dimensional (3D) network arising from one-dimensional (1D) supramolecular helical chains, stabilized by N—H...O and O—H...O hydrogen bonds. In the case of Matrine–SA, the matrine cation is interconnected via hydrogen bonds with salicylate anions and water molecules, also forming a 1D helical motif. The structure of the hydrate form, Matrine–H, is reported again with the disordered solvent molecules accurately located. To further elucidate the structural attributes, Hirshfeld surface analysis and fingerprint plots are employed, offering a nuanced perspective on the intermolecular contacts and interactions within these crystalline forms.
On the importance of crystal structures for organic thin film transistors
Authors: Schweicher Guillaume , Das Susobhan , Resel Roland , Geerts Yves
Published: September 2024

Historically, knowledge of the molecular packing within the crystal structures of organic semiconductors has been instrumental in understanding their solid-state electronic properties. Nowadays, crystal structures are thus becoming increasingly important for enabling engineering properties, understanding polymorphism in bulk and in thin films, exploring dynamics and elucidating phase-transition mechanisms. This review article introduces the most salient and recent results of the field.
Are farmers willing to pay for low-carbon agriculture? Evidence from China
Authors: Yang Wanping , Mou Muge , Mu Lan , Zeng Xuanwen
Published: September 2024

Purpose

Reducing carbon emissions in agriculture is vital for fostering sustainable agricultural growth and promoting ecological well-being in rural areas. The adoption of Low-Carbon Agriculture (LCA) by farmers holds great potential to accomplish substantial reductions in carbon emissions. The purpose of this study is to explore the farmers' preference and willingness to engage in LCA.

Design/methodology/approach

This study employs the Choice Experiment (CE) method to examine farmers' preferences and willingness to adopt LCA, using field survey data of 544 rural farmers in the Weihe River Basin between June and July 2023. We further investigate differences in willingness to pay (WTP) and personal characteristics among different farmer categories.

Findings

The empirical results reveal that farmers prioritize government-led initiatives providing pertinent technical training as a key aspect of the LCA program. Farmers' decisions to participate in LCA are influenced by factors including age, gender, education and the proportion of farm income in household income, with their evaluations further shaped by subjective attitudes and habits. Notably, we discovered that nearly half of the farmers exhibit indifference towards LCA attributes.

Originality/value

To the best of the authors' knowledge, this study is the first to investigate farmers' attitudes toward LCA from their own perspectives and to analyze the factors influencing them from both subjective and objective standpoints. This study presents a fresh perspective for advocating LCA, bolstering rural ecology and nurturing sustainable development in developing nations.
Optimize data association of point cloud to improve the quality of mapping and positioning
Authors: Zhou Guangbing , Quan Letian , Huang Kaixuan , Zhang Shunqing , Xu Shugong
Published: September 2024

Purpose

Accurate mapping is crucial for the positioning and navigation of mobile robots. Recent advancements in algorithms and the accuracy of LiDAR sensors have led to a gradual improvement in map quality. However, challenges such as lag in closing loops and vignetting at map boundaries persist due to the discrete and sparse nature of raster map data. The purpose of this study is to reduce the error of map construction and improve the timeliness of closed loop.

Design/methodology/approach

In this letter, the authors introduce a method for dynamically adjusting point cloud distance constraints to optimize data association (ODA-d), effectively addressing these issues. The authors propose a dynamic threshold optimization method for matching point clouds to submaps during scan matching.

Findings

Large deviations in LiDAR sensor point cloud data, when incorporated into the submap, can result in irreparable errors in correlation matching and loop closure optimization. By implementing a data association framework with double constraints and dynamically adjusting the matching threshold, the authors significantly enhance submap quality. In addition, the authors introduce a dynamic fusion method that accounts for both submap size and the distance between submaps during the mapping process. ODA-d reduces errors between submaps and facilitates timely loop closure optimization.

Originality/value

The authors validate the localization accuracy of ODA-d by examining translation and rotation errors across three open data sets. Moreover, the authors compare the quality of map construction in a real-world environment, demonstrating the effectiveness of ODA-d.
A panel data regression model for defense merger and acquisition activity
Authors: Mack Corey , Koschnick Clay , Brown Michael , Ritschel Jonathan D. , Lucas Brandon
Published: September 2024

Purpose

This paper examines the relationship between a prime contractor's financial health and its mergers and acquisitions (M&A) spending in the defense industry. It aims to provide models that give the United States Department of Defense (DoD) indications of future M&A activity, informing decision-makers and contributing to ensuring competitive markets that benefit the consumer.

Design/methodology/approach

The study uses panel data regression models on 40 companies between 1985 and 2021. The company's financial health is assessed using industry-standard financial ratios (i.e. measures of profitability, efficiency, solvency and liquidity) while controlling for economic factors such as national productivity, defense budgets and firm size.

Findings

The results show a significant relationship between efficiency and M&A spending, indicating that companies with lower efficiency tend to spend more on M&As. However, there was no significant relationship between M&A spending and a company's profitability or solvency. These results were consistent with previous research and the study's hypotheses for profitability and solvency. However, the effect of liquidity was the opposite of the expected result, possibly due to the defense industry's different view on liquidity compared to previous research.

Originality/value

The paper provides insights into the relationship between a prime contractor's financial health and its M&A spending, a topic with limited research. The findings can inform policymakers and regulators on the industrial base's future M&A activity, ensuring competitive markets that benefit the consumer.
Yeast polysaccharides: The environmentally friendly polysaccharides with broad application potentials
Authors: Dong Wenjing , Li Yichen , Xue Shurong , Wen Fengge , Meng Demei , Zhang Yuyu , Yang Rui
Published: September 2024

Yeast cell wall (YCW) polysaccharides, including β‐glucans, mannans, chitins, and glycogens, can be extracted from the waste of beer industry. They are environmentally friendly, abundant, inexpensive raw materials, and have shown broad biological activities and application potentials. The exploitation of yeast polysaccharides is of great importance for environmental protection and resource utilization. This paper reviews the structural features and preparation of YCW polysaccharides. The solubility and emulsification of yeast polysaccharides and the properties of binding metal ions are presented. In addition, biological activities such as blood glucose and lipid lowering, immune regulation, antioxidant, promotion of intestinal health, and promotion of wound healing are proposed, highlighting the beneficial effects of yeast polysaccharides on human health. Through modification, the physical and chemical properties of yeast polysaccharides are changed, which emphasizes the promotion of their biological activities and properties. In addition, the food applications of yeast polysaccharides, including the food packaging film, emulsifier, thickening agent, and fat alternatives, are focused and discussed.
Effects of cholesterol‐lowering probiotic fermentation on the active components and in vitro hypolipidemic activity of sea buckthorn juice
Authors: Fan Ying , Shang Yueling , Li Fengwei , Liu Jinbin , Wang Dujun , Zhang Ya , Yu Xiaohong , Wang Wei
Published: September 2024

Sea buckthorn has lipid‐lowering properties and is widely used in the development of functional foods. In this study, a probiotic (Lactobacillus plantarum, Lp10211) with cholesterol‐lowering potential and acid and bile salt resistant was screened for the fermentation of sea buckthorn juice. Changes in the active ingredients, such as sugars and phenolics, before and after fermentation, as well as their in vitro lipid‐lowering activities, were compared. The contents of reducing and total sugars decreased substantially after fermentation. Lp10211 primarily utilized fructose for growth and reproduction, with a utilization rate of 76.9%. The phenolic compound content of sea buckthorn juice increased by 37.06% after fermentation and protected the phenolic components from degradation (protocatechuic and p‐coumaric acids) and produced new polyphenol (shikimic acid). Enhanced inhibition of pancreatic lipase activity (95.42%) and cholesterol micellar solubility (59.15%) was evident. The antioxidant properties of the fermentation broth were improved. Notably, Lp10211 preserved the color and reversed browning in sea buckthorn juice. The collective findings indicate that fermentation of sea buckthorn juice by Lp10211 may enhance the functional components and lipid‐lowering activity of sea buckthorn, which may provide a new approach for the development of lipid‐lowering foods.
Complications after benign gynecologic surgery—How are they captured in register‐based research? A national register study in Sweden
Authors: Collins Elin , Liv Per , Strandell Annika , Furberg Maria , Ehrström Sophia , Pålsson Mathias , Idahl Annika
Published: September 2024

Introduction

The evidence on complication rates after gynecological surgery is based on multiple types of studies, and the level of evidence is generally low. We aimed to validate the registration of complications in the Swedish National Quality Register of Gynecological Surgery (GynOp), by cross‐linkage to multiple national registers.

Material and Methods

A national register‐based study using prospectively collected data was conducted, including women who had surgery on the uterus or adnexa for benign indications from January 1, 2017, to December 31, 2020. In Sweden, complications after gynecological surgery are registered in GynOp, and if the complication has rendered any interaction with healthcare, it is also in national health registers. The GynOp register, the National Patient Register, the Prescribed Drugs Register, and the Cause of Death Register were cross‐linked. Complications in GynOp and complications according to ICD10 were analyzed, as well as the cause of death if occurring within 3 months of surgery and prescription of antibiotics ≤30 days. Comparisons between the registries were descriptive.

Results

During the study period 32 537 surgeries were performed, of which 26 214 (80.6%) were minimally invasive. Complications were reported in GynOp for 569 women (1.7%) at surgery, 1045 (3.2%) while admitted, and 3868 (13.7%) from discharge to 3 months after surgery. In comparison, according to the Patient Register, 2254 women (6.9%) had postoperative complications within 3 months of discharge (difference of 6.8 percentage points [95% confidence interval 6.2–7.2]). Furthermore, 4117 individuals (12.7%) had a prescription of antibiotics ≤30 days which could indicate a postoperative infection. The rates of hemorrhage, wound dehiscence, and thrombosis were comparable between GynOp and the Patient Register while diagnoses not leading to contact with specialized care had higher rates in the quality register. The coverage of complications was 79.1% in GynOp and 46.1% in the Patient Register, using the total number of complications from both registers as the denominator.

Conclusions

A higher frequency of complications is captured in GynOp than in the National Patient Register. Patient‐reported outcomes assessed by a physician are beneficial in identifying complications indicating the importance of structured pre‐defined follow‐up over a set period.