bluuebunny/crossref_metadata_2025 huggingface dataset:
A common pathway controls cell size in the sepal and leaf epidermis leading to a non-random pattern of giant cells
Authors: Clark Frances K. , Weissbart Gauthier , Wang Xihang , Harline Kate , Li Chun-Biu , Formosa-Jordan Pau , Roeder Adrienne H. K.
Published: July 2024

Arabidopsis leaf epidermal cells have a wide range of sizes and ploidies, but how large cells are spatially patterned alongside smaller cells remains unclear. Here, we demonstrate that the same genetic pathway that creates giant cells in sepals is also responsible for their formation in the leaf epidermis. In both sepals and leaves, giant cells are scattered among smaller cells; therefore, we asked whether the spatial arrangement of giant cells is random. By comparing sepal and leaf epidermises with computationally generated randomized tissues we show that giant cells are clustered more than is expected by chance. Our cell-autonomous and stochastic computational model recapitulates the observed giant cell clustering, indicating that clustering emerges as a result of the cell division pattern. Overall, cell size patterning is developmentally regulated by common mechanisms in leaves and sepals rather than a simple byproduct of cell growth.

Teaser

The spatial pattern of giant cells becomes non-random as the surrounding cells divide.
Context-dependence of deterministic and nondeterministic contributions to closed-loop steering control
Authors: Egger Seth W. , Keemink Sander W. , Goldman Mark S. , Britten Kenneth H.
Published: July 2024

In natural circumstances, sensory systems operate in a closed loop with motor output, whereby actions shape subsequent sensory experiences. A prime example of this is the sensorimotor processing required to align one’s direction of travel, or heading, with one’s goal, a behavior we refer to as steering. In steering, motor outputs work to eliminate errors between the direction of heading and the goal, modifying subsequent errors in the process. The closed-loop nature of the behavior makes it challenging to determine how deterministic and nondeterministic processes contribute to behavior. We overcome this by applying a nonparametric, linear kernel-based analysis to behavioral data of monkeys steering through a virtual environment in two experimental contexts. In a given context, the results were consistent with previous work that described the transformation as a second-order linear system. Classically, the parameters of such second-order models are associated with physical properties of the limb such as viscosity and stiffness that are commonly assumed to be approximately constant. By contrast, we found that the fit kernels differed strongly across tasks in these and other parameters, suggesting context-dependent changes in neural and biomechanical processes. We additionally fit residuals to a simple noise model and found that the form of the noise was highly conserved across both contexts and animals. Strikingly, the fitted noise also closely matched that found previously in a human steering task. Altogether, this work presents a kernel-based analysis that characterizes the context-dependence of deterministic and non-deterministic components of a closed-loop sensorimotor task.

New and noteworthy

We use nonparametric systems identification techniques to assess the context-dependence of deterministic and nondeterministic contributions to a closed-loop behavior. Classical approaches assume a fixed transformation between sensory input and motor output. Here, we reveal strong changes to the measured sensorimotor transformations with behavioral context. In contrast, noise within the transformation exhibited a consistent form across contexts, subjects, and species. Together, this work demonstrates how context affects the systematic and stochastic components of a closed-loop behavior.
Comparative Analysis of Antioxidant Activity, ROS, and Relative Water Content Between Red and Green Cabbage
Authors: Sojib Md. Rayhan , Methela Nusrat Jahan , Das Biswajit , Siddique Md Nure Adil , Sultana Sadia , Karim Ataul , Islam Rafiqul , Jone Md Jahid Hasan
Published: July 2024

Cabbage, the second largest leafy vegetable, is highly valued for its nutritional richness and versatility. As health consciousness increases, the worldwide demand for cabbage continues to grow steadily. Cabbages come in various forms, varying in size, color, texture, and nutritional properties. An experiment was conducted to distinguish significant differences in relative water content (RWC of leaf and RWC of head), relative oxygen species (MDA and H2O2), and antioxidant properties (POD, APX, and CAT) between red and green cabbage varieties. Cabbage samples were grown under fertilizer and control conditions to observe the impact of fertilizers on the acquisition of these properties. The results indicated that fertilizer application positively influenced the acquisition of relative water content, relative oxygen species, and antioxidant properties in both cabbage varieties. The results emphasized that red cabbage excelled in antioxidants and ROS levels, containing higher amounts compared to green cabbage. Conversely, green cabbage showed greater relative water content in both cultivation conditions. These findings suggest that consumers seeking higher antioxidant and ROS levels in their diet may benefit from incorporating more red cabbage into their meals. Further research into the mechanisms behind differences in red and green cabbage could inform breeding programs, enhancing nutritional traits for agricultural and dietary purposes.
Single field evolution rule governs the dynamics of representational drift in mouse hippocampal dorsal CA1 region
Authors: Chen Cong , Yao Shuyang , Cheng Sihui , Li Ang , Yan Yusen , Zhang Xiang , Liu Yuanjing , Wang Yumeng , Cao Qichen , Miao Chenglin
Published: July 2024

How the brain reconciles dynamism with stability to balance learning and reliable memory storage has not yet been fully understood. To address the critical question, we longitudinally recorded place cells in the hippocampal dorsal CA1 region over 7 to 56 days, utilizing multiple goal-oriented navigation paradigms across various environments. We found that over 80% of place cells displayed multiple fields, undergoing complex evolution events including field disappearance, formation, and retention. Place fields from the same neuron showed limited coordination (∼5%), with a preference for synchronized changes. We further uncovered the single field evolution rule: the longer a field remains active, the more likely it is to continue being active; conversely, the longer a field remains inactive, the less likely it is to recover the future fate of a place field depends on its past activity. Mathematical modeling revealed that this rule sufficiently demonstrates the growing stability of the dCA1 spatial representation at the population level.
Assessing Healthy Vaccinee Effect in COVID-19 Vaccine Effectiveness Studies: A National Cohort Study in Qatar
Authors: Chemaitelly Hiam , Ayoub Houssein H. , Coyle Peter , Tang Patrick , Hasan Mohammad R. , Yassine Hadi M. , Al Thani Asmaa A. , Al-Kanaani Zaina , Al-Kuwari Einas , Jeremijenko Andrew , Kaleeckal Anvar Hassan , Latif Ali Nizar , Shaik Riyazuddin Mohammad , Abdul-Rahim Hanan F. , Nasrallah Gheyath K. , Al-Kuwari Mohamed Ghaith , Al-Romaihi Hamad Eid , Al-Thani Mohamed H. , Al-Khal Abdullatif , Bertollini Roberto , Butt Adeel A. , Abu-Raddad Laith J.
Published: July 2024

Background

This study investigated the presence of the healthy vaccinee effect—the imbalance in health status between vaccinated and unvaccinated individuals—in two COVID-19 vaccine effectiveness studies involving primary series and booster vaccinations. It also examined the temporal patterns and variability of this effect across different subpopulations by analyzing the association between COVID-19 vaccination and non-COVID-19 mortality in Qatar.

Methods

Two matched, retrospective cohort studies assessed the incidence of non-COVID-19 death in national cohorts of individuals with a primary series vaccination versus no vaccination (two-dose analysis), and individuals with three-dose (booster) vaccination versus primary series vaccination (three-dose analysis), from January 5, 2021, to April 9, 2024.

Results

The adjusted hazard ratio (aHR) for non-COVID-19 death was 0.76 (95% CI: 0.64-0.90) in the two-dose analysis and 0.85 (95% CI: 0.67-1.07) in the three-dose analysis. In the first six months of follow-up in the two-dose analysis, the aHR was 0.35 (95% CI: 0.27-0.46); however, the combined analysis of all subsequent periods showed an aHR of 1.52 (95% CI: 1.19-1.94). In the first six months of follow-up in the three-dose analysis, the aHR was 0.31 (95% CI: 0.20-0.50); however, the combined analysis of all subsequent periods showed an aHR of 1.37 (95% CI: 1.02-1.85). The overall effectiveness of the primary series and third-dose vaccinations against severe, critical, or fatal COVID-19 was 95.9% (95% CI: 94.0-97.1) and 34.1% (95% CI: −46.4-76.7), respectively. Subgroup analyses showed that the healthy vaccinee effect is pronounced among those aged 50 years and older and among those more clinically vulnerable to severe COVID-19.

Conclusion

A strong healthy vaccinee effect was observed in the first six months following vaccination. This effect may have stemmed from a lower likelihood of vaccination among seriously ill, end-of-life individuals, and less mobile elderly populations.
A retrograde transit filter mediated by optineurin controls mitostasis in distal axons
Authors: Marahori Natalia A. , Gailer Barbara , Schifferer Martina , Kleele Tatjana , Iatroudi Anna , Hannan Shabab B. , Avramopoulos Petros , Engelhardt Stefan , Lakadamyali Melike , Brill Monika S. , Misgeld Thomas
Published: July 2024

The mechanisms of mitochondrial homeostasis in neurons—‘mitostasis’—are enigmatic and disease-prone, given a neuron’s large synaptic pool of mitochondria. To better understand mitostasis in mature mouse motor axons, we used ex vivo optical pulse-chase measurements of mitochondrial volume flux and identified a reiterative degradation system near presynaptic terminals and distal paranodes, which accounts for 75% of mitochondrial turnover in synapses. This distal filter system captures dysfunctional mitochondria from the retrograde stream and redirects them for lysosomal degradation. It depends on optineurin, a motor neuron disease-related mitophagy adaptor, but not on PINK1 and parkin, implicating a non-canonical mitophagy pathway. In presymptomatic motor neuron disease models, where retrograde transport is disrupted, the fraction of removed mitochondria is increased. Thus, we identify a new mitostasis system in distal axons with a cascade of checkpoints for local mitophagy, which normally maintains mitochondrial mass balance but is disrupted early in degenerative axonopathies.
Rapid liquid biopsy assessment through gene profiling from the kidney biopsy transport medium: a technical validation and a proof-of-concept pilot study
Authors: Li Ziyang , Welters Marij J.P. , de Vries Aiko P.J. , Bruijn Jan A. , Baelde Hans J. , Kers Jesper
Published: July 2024

Background

Rapid diagnosis is pivotal in kidney disease for timely and targeted treatment. Conventional microscopic and molecular assessments from biopsy tissues rely on extra sample processing (e.g., formalin-fixation, paraffin-embedding (FFPE)) or an extra biopsy core (e.g., Molecular Microscope Diagnostic System [MMDx]), making same-day diagnosis impractical. Therefore, we introduce a novel and freely accessible material, the biopsy transport medium (BTM), which can serve as a source of biomarkers with high potential and is promising for accelerating the assessment workflow.

Methods

Biopsies were cut from tumor-free tissues obtained from nephrectomies to create BTM mimics for homogenization. We optimized the RNA extraction procedure from BTM by investigating crucial steps in the process. We measured the quantity and integrity of the RNA and different biomarkers derived from BTM through qPCR. Additionally, we performed gene signature profiling on BTM using the Banff Human Organ Transplant (B-HOT) panel in the NanoString nCounter platform as a proof-of-concept study.

Results

The storage time (the duration a biopsy is stored in the BTM), ranging from 0.5 to 24 hours did not significantly affect RNA quality and yield. Differential gene expression analysis on allograft rejection BTM described specific profiles related to rejection. A significant correlation was observed between rejection-related transcripts and the corresponding Banff lesion scores.

Conclusion

This study validated that the BTM can provide transcriptomic information relevant to the state of the kidney. The proof-of-concept study demonstrated that BTM has great potential for reflecting the status of the transplanted kidney. Tailored qPCR panels could allow for fast (same-day) molecular diagnosis.
12-Lipoxygenase inhibition delays onset of autoimmune diabetes in human gene replacement mice
Authors: Nargis Titli , Muralidharan Charanya , Enriquez Jacob R. , Wang Jiayi E. , Kaylan Kerim , Chakraborty Advaita , Pratuangtham Sarida , Figatner Kayla , Nelson Jennifer B. , May Sarah C. , Nadler Jerry L. , Boxer Matthew B. , Maloney David J. , Tersey Sarah A. , Mirmira Raghavendra G.
Published: July 2024

Type 1 diabetes (T1D) is characterized by the autoimmune destruction of insulin-producing β cells and involves an interplay between β cells and cells of the innate and adaptive immune systems. We investigated the therapeutic potential of targeting 12-lipoxygenase (12-LOX), an enzyme implicated in inflammatory pathways in β cells and macrophages, using a mouse model in which the endogenous mouseAlox15gene is replaced by the humanALOX12gene. Our finding demonstrated that VLX-1005, a potent 12-LOX inhibitor, effectively delayed the onset of autoimmune diabetes in human gene replacement non-obese diabetic mice. By spatial proteomics analysis, VLX-1005 treatment resulted in marked reductions in infiltrating T and B cells and macrophages with accompanying increases in immune checkpoint molecule PD-L1, suggesting a shift towards an immune-suppressive microenvironment. RNA sequencing analysis of isolated islets and polarized proinflammatory macrophages revealed significant alteration of cytokine-responsive pathways and a reduction in interferon response after VLX-1005 treatment. Our studies demonstrated that theALOX12human replacement gene mouse provides a platform for the preclinical evaluation of LOX inhibitors and supports VLX-1005 as an inhibitor of human 12-LOX that engages the enzymatic target and alters the inflammatory phenotypes of islets and macrophages to promote the delay of autoimmune diabetes.
Overcrowding Drives Tumor Invasion by Inducing Nanotopographical Transition of Plasma Membrane
Authors: Zhao Xinbin , Tan Min , Li Long , Lin Xubo , Li Zekun , Wang Xiaohuan , Song Bingqi , Guo Zheng , Chen Tailin , Hou Sen , Fan Jiehou , Wang Shijiang , Zhang Yun , Fan Yubo , Du Jing
Published: July 2024

During the development from epithelial neoplasms to invasive carcinoma, uncontrolled growth and proliferation in a confined space cause tumor cells survive in a prolonged overcrowding condition. However, the role of this aberrant physical stimulus induced by overcrowding in the invasiveness acquisition of epithelial cells remains unclear. Here, we first identified overcrowded cancer cells were more abundant at invasive foci in human cancer samples and mouse xenograft models. Combining with mechanical modelling, genetic manipulations and biophysical measurements, we revealed that prolonged overcrowding induces retentive invasiveness in cancer cells by triggering nanocorrugated topographic transition of plasma membrane. Further study demonstrated that the nanocorrugated topographic transition is induced by overcrowding-increased Laplace pressure and disrupts lipid raft-like domains organization to promote tumor invasion. Finally, suppressing nanocorrugated topographical transition of plasma membrane by strengthening membrane-cortex-attachment resists to tumor cell invasion in a mouse model of oncogenesis. This work reveals the profound effect of tissue-scale mechanical revolution-induced biophysical transition of cancer cells in driving tumor invasion.
Using DeepLabCut-Live to probe state dependent neural circuits of behavior with closed-loop optogenetic stimulation
Authors: Gonzalez Melissa , Gradwell Mark A. , Thackray Joshua K , Patel Komal R. , Temkar Kanaksha K. , Abraira Victoria E.
Published: July 2024

Background

Closed-loop behavior paradigms enable us to dissect the state-dependent neural circuits underlying behavior in real-time. However, studying context-dependent locomotor perturbations has been challenging due to limitations in molecular tools and techniques for real-time manipulation of spinal cord circuits.

New Method

We developed a novel closed-loop optogenetic stimulation paradigm that utilizes DeepLabCut-Live pose estimation to manipulate primary sensory afferent activity at specific phases of the locomotor cycle in mice. A compact DeepLabCut model was trained to track hindlimb kinematics in real-time and integrated into the Bonsai visual programming framework. This allowed an LED to be triggered to photo-stimulate sensory neurons expressing channelrhodopsin at user-defined pose-based criteria, such as during the stance or swing phase.

Results

Optogenetic activation of nociceptive TRPV1+sensory neurons during treadmill locomotion reliably evoked paw withdrawal responses. Photoactivation during stance generated a brief withdrawal, while stimulation during swing elicited a prolonged response likely engaging stumbling corrective reflexes.

Comparison with Existing Methods: This new method allows for high spatiotemporal precision in manipulating spinal circuits based on the phase of the locomotor cycle. Unlike previous approaches, this closed-loop system can control for the state-dependent nature of sensorimotor responses during locomotion.

Conclusions

Integrating DeepLabCut-Live with optogenetics provides a powerful new approach to dissect the context-dependent role of sensory feedback and spinal interneurons in modulating locomotion. This technique opens new avenues for uncovering the neural substrates of state-dependent behaviors and has broad applicability for studies of real-time closed-loop manipulation based on pose estimation.

Manuscript

Highlights

Closed-loop system probes state-dependent behaviors at pose-modulated instances

Bonsai integrates DeepLabCut models for real-time pose estimation during locomotion

Phase-dependent TRPV1+sensory afferent photostimulation elicits context-specific withdrawal responses
Spatial dynamics of mammalian brain development and neuroinflammation by multimodal tri-omics mapping
Authors: Zhang Di , Rubio Rodríguez-Kirby Leslie A , Lin Yingxin , Song Mengyi , Wang Li , Wang Lijun , Kanatani Shigeaki , Jimenez-Beristain Tony , Dang Yonglong , Zhong Mei , Kukanja Petra , Wang Shaohui , Chen Xinyi Lisa , Gao Fu , Wang Dejiang , Xu Hang , Lou Xing , Liu Yang , Chen Jinmiao , Sestan Nenad , Uhlén Per , Kriegstein Arnold , Zhao Hongyu , Castelo-Branco Gonçalo , Fan Rong
Published: July 2024

The ability to spatially map multiple layers of the omics information over different time points allows for exploring the mechanisms driving brain development, differentiation, arealization, and alterations in disease. Herein we developed and applied spatial tri-omic sequencing technologies, DBiT ARP-seq (spatial ATAC–RNA–Protein-seq) and DBiT CTRP-seq (spatial CUT&Tag– RNA–Protein-seq) together with multiplexed immunofluorescence imaging (CODEX) to map spatial dynamic remodeling in brain development and neuroinflammation. A spatiotemporal tri-omic atlas of the mouse brain was obtained at different stages from postnatal day P0 to P21, and compared to the regions of interest in the human developing brains. Specifically, in the cortical area, we discovered temporal persistence and spatial spreading of chromatin accessibility for the layer-defining transcription factors. In corpus callosum, we observed dynamic chromatin priming of myelin genes across the subregions. Together, it suggests a role for layer specific projection neurons to coordinate axonogenesis and myelination. We further mapped the brain of a lysolecithin (LPC) neuroinflammation mouse model and observed common molecular programs in development and neuroinflammation. Microglia, exhibiting both conserved and distinct programs for inflammation and resolution, are transiently activated not only at the core of the LPC lesion, but also at distal locations presumably through neuronal circuitry. Thus, this work unveiled common and differential mechanisms in brain development and neuroinflammation, resulting in a valuable data resource to investigate brain development, function and disease.
Parallel evolution of methyltransferases leads to vobasine biosynthesis inTabernaemontana elegansandCatharanthus roseus
Authors: Farzana Maisha , Richardson Matthew Bailey , Deschênes Daniel André Ramey , Mai Zhan , Njoku Destiny Ichechi , Deslongchamps Ghislain , Qu Yang
Published: July 2024

Monoterpenoid indole alkaloids (MIA) are one of the largest and most complex alkaloid class in nature, boasting many clinically significant drugs such as anticancer vinblastine and antiarrhythmic ajmaline. Many MIAs undergo nitrogenN-methylation, altering their reactivity and affinity to the biological targets through a straightforward reaction. Remarkably, all known MIAN-methyltransferases (NMT) originate from the neofunctionalization of ancestral γ-tocopherolC-methyltransferases (γTMTs), a phenomenon seemingly unique to the Apocynaceae family. In this study, we unveil and characterize a new γTMT-like enzyme from the plantTabernaemontana elegans(toad tree): perivineNβ-methyltransferase (TePeNMT). TePeNMT and other homologs form a distinct clade in our phylogenetic study, setting them apart from other γTMTs and γTMT-like NMTs discovered to date. Enzyme kinetic experiments and enzyme homology modeling studies reveal the significant differences in enzyme active sites between TePeNMT and CrPeNMT, a previously characterized perivineNβ-methyltransferase fromCatharanthus roseus(Madagascar periwinkle). Collectively, our findings suggest that parallel evolution of ancestral γTMTs may be responsible for the occurrence of perivineN-methylation inT. elegansandC. roseus.
Synergy and antagonism in the integration of BCR and CD40 signals that control B-cell proliferation
Authors: Huang Helen , Vaidehi Narayanan Haripriya , Hoffmann Alexander
Published: July 2024

In response to infection or vaccination, a successful antibody response must enrich high-affinity antigen-reactive B-cells through positive selection, but eliminate auto-reactive B-cells through negative selection. B-cells receive signals from the B-cell receptor (BCR) which binds the antigen, and the CD40 receptor which is stimulated by neighboring T-cells that also recognize the antigen. How BCR and CD40 signaling are integrated quantitatively to jointly determine B-cell fate decision and proliferation remains unclear. To investigate this, we developed a differential-equations-based model of the BCR and CD40 signaling networks activating NFκB. Our model accurately recapitulates the NFκB dynamics of B-cells stimulated through their BCR and CD40 receptors, correctly predicting that costimulation induces more NFκB activity. However, when linking it to established cell fate decision models of cell survival and cell cycle control, it predicted potentiated population expansion that was not observed experimentally. We found that this discrepancy was due to a time-dependent functional antagonism exacerbated by BCR-induced caspase activity that can trigger apoptosis in founder cells, unless NFκB-induced survival gene expression protects B-cells in time. Guided by model predictions, sequential co-stimulation experiments revealed how the temporal dynamics of BCR and CD40 signaling control the fate decision between negative and positive selection of B-cell clonal expansion. Our quantitative findings highlight a complex non-monotonic integration of BCR and CD40 signals that is controlled by a balance between NFκB and cell-death pathways, and suggest a mechanism for regulating the stringency of B-cell selection during an antibody response.

Highlights

CD40 and BCR signaling in B-cells synergize to potentiate NFκB cRel activation

BCR-apoptotic signaling may enhance or antagonize CD40-driven proliferation

BCR-induced apoptosis may be rescued by CD40 within a temporal window

A mathematical model reveals regulators of the dose-dependent selection stringency
Live-Cell Quantification Reveals Viscoelastic Regulation of Synapsin Condensates by α-Synuclein
Authors: Wang Huan , Hoffmann Christian , Tromm Johannes V , Su Xiao , Elliott Jordan , Wang Han , Baum Jean , Pang Zhiping P. , Milovanovic Dragomir , Shi Zheng
Published: July 2024

Synapsin and α-synuclein represent a growing list of condensate-forming proteins where the material states of condensates are directly linked to cellular functions (e.g., neurotransmission) and pathology (e.g., neurodegeneration). However, quantifying condensate material properties in living systems has been a significant challenge. To address this, we develop MAPAC (micropipette aspiration and whole-cell patch clamp), a platform that allows direct material quantification of condensates in live cells. We find 10,000-fold variations in the viscoelasticity of synapsin condensates, regulated by the partitioning of α-synuclein, a marker for synucleinopathies. Through in vitro reconstitutions, we identify 4 molecular factors that distinctly regulate the viscosity and interfacial tension of synapsin condensates, verifying the cellular effects of α-synuclein. Overall, our study provides unprecedented quantitative insights into the material properties of neuronal condensates and reveals a crucial role of α-synuclein in regulating condensate viscoelasticity. Furthermore, we envision MAPAC applicable to study a broad range of condensates in vivo.
The Role of TandemHeartTMcombined with ProtekDuoTMas Right Ventricular Support Device: A Simulation Approach
Authors: De Lazzari Beatrice , Badagliacca Roberto , Capoccia Massimo , Maybauer Marc O , De Lazzari Claudio
Published: July 2024

Right ventricular failure increases short-term mortality in the setting of acute myocardial infarction, cardiogenic shock, advanced left-sided heart failure and pulmonary hypertension. Right ventricular failure remains quite a challenging condition to manage in view of its complex background and still incomplete understanding of its pathophysiology. Percutaneous and surgically implanted right ventricular assist devices (RVADs) have been investigated in different clinical settings. The use of the ProtekDuoTM(LivaNova, London, UK) is currently a promising approach due to its features such as groin-free approach leading to early mobilisation, easy percutaneous deployment, compatibility with different pumps and oxygenators, and adaptability to different configurations. The aim of this work was to simulate the behaviour of the TandemHeartTMpump applied “in series” and “in parallel“ mode and the combination of TandemHeartTMand ProtekDuoTMcannula as right ventricular assist device using CARDIOSIM©software simulator platform. The effects induced on the main hemodynamic and energetic variables were analysed for both the right atrial-pulmonary arterial and right ventricular-pulmonary arterial configuration with different pump rotational speed and following of Milrinone administration. The TandemHeartTMincreased right ventricular end systolic volume by 10%, larger increases were evident for higher speeds (6000 and 7500 rpm) and connections with 21 Fr inflow and 17 Fr outflow cannula, respectively. Both TandemHeartTMand ProtekDuoTMsupport increased left ventricular preload. When different RVAD settings were used, Milrinone therapy increased the left ventricular pressure-volume area and decreased the right pressure-volume area slightly. A reduction in oxygen consumption (demand) was observed with reduced right stroke work and pressure volume area and increased oxygen supply (coronary blood flow).
Consistent long-distance foraging flights across years and seasons at colony level in a Neotropical bat
Authors: Calderón-Capote María C. , van Toor Mariëlle L. , O’Mara M. Teague , Bayer Travis D. , Crofoot Margaret C. , Dechmann Dina K.N.
Published: July 2024

All foraging animals face a trade-off: how much time should they invest in exploitation of known resources versus exploration to discover new resources? For group-living central place foragers, balancing these competing goals poses particular challenges. The availability of social information may discourage individuals from investing in risky, expensive but possibly rewarding exploration. We GPS-tracked groups of greater spear-nosed bats (Phyllostomus hastatus) from three colonies on Isla Colón in Panamá. In the dry season, when these omnivores forage on the nectar of ephemeral balsa flowers (Ochroma pyramidale), bats consistently travelled long distances to remote, colony-specific foraging areas, bypassing flowering trees closer to their roosts. They continued to use these same areas in the wet season, when feeding on a diverse, presumably ubiquitously distributed diet, but also visited other, similarly distant foraging areas. Foraging areas were shared within, but not always between colonies. Our longitudinal dataset suggests that bats from each colony invest in long-distance commutes to socially learned shared foraging areas, bypassing other available food patches. Rather than investing in exploration to find nearby resources or engaging in a win-stay lost-shift foraging strategy, these bats follow colony specific behaviours consistent with the existence of culturally transmitted preferences for specific feeding grounds.
Exploration of Flavonoids to identify Potential Therapeutic Compounds by Targeting the Non-Structural V protein of Nipah Virus
Authors: Ahmad S Rehan , Zeyaullah Md. , AlShahrani Abdullah M. , Khan Mohammad Suhail , Ali Haroon , Muzammil Khursheed , Mohieldin Ali , AG Altijani Abdelrhman , Dawria Adam , Mohamed Awad Osman Abdalla , Kalam Abul
Published: July 2024

Researchers are interested in a number of interdisciplinary approaches that might speed up and reduce the cost of creating new medications. This work aims to determine target proteins and choose a lead medication to combat the Nipah Virus. Following a study of the literature, we discover the non-structural V protein (UniProt ID: Q997F2). I-TASSER was used to estimate the 3D structure. We examined the flavonoid dataset in search of a strong inhibitor. Pyrx is used to use AutoDock Vina for docking. The interactions between the drug and the target protein binding were examined using BIOVIA Discovery Studio. Desmond’s Molecular Dynamics Simulation (MD simulation) was used to study the stability of protein and inhibitor complexes in a physiological environment. Based on our research, we have designed two lead compounds that lessen the virus’s effect. This discovery will benefit science as it may lead to the development of novel medications. The newly discovered natural compounds showed promise as inhibitors, showing less adverse effects and more efficiency.
Detection of Potential Phytochemicals against ctxAB Toxin to Combat Cholera
Authors: Akter Yasmin , Rahman Khalilur , Reza Md Selim , Al-Mamun Abdullah , Alam Munirul , Haque Mollah Md Nurul , Monir Md. Mamun
Published: July 2024

Vibrio choleraeis a gram-negative curved rod-shaped bacterium responsible for cholera, an intestinal infection characterized by severe acute watery diarrhea that can be fatal if untreated. The major virulence factor forVibrio choleraeis cholera toxin (ctx), a potent toxin which has two subunits, A and B (ctxAB), that are crucial for the progression of the deadly disease. The B subunit is a pentavalent protein that binds to the intestinal mucosa to allow internalization of the A subunit to initiate rice-watery diarrhea. This study explored potential phytochemicals to inhibit the B subunit from binding to the host mucosa by examining their interaction withctxB. Proteins encoded by the three genotypes of thectxBgene (ctxB1, ctxB3, andctxB7) present in the El Tor biotype strains ofV. choleraeO1 responsible for the currently ongoing seventh cholera pandemic were targeted. Analysis of 52 phytochemicals obtained from PubChem identified a group of phytochemicals based on their binding affinity scores with the proteins ofctxBgenotypes. Assessment of drug-likeliness and toxicity risk highlighted two phytochemicals, Limonin and Emodin, as the best potential candidates for inhibiting the mode of action of cholera toxin. Molecular dynamic (MD) simulation-based MM-PBSA analysis suggested these compounds stably interact with the receptors. Molecular docking and molecular dynamic simulations revealed that these phytochemicals might have potential to inhibit the cholera toxin function and reduce the severity of cholera.

Author Summary

Cholera toxin (ctx) subunits A and B (ctxAB) play a significant role in the disease, with the B subunit facilitating the binding of the toxin to the intestinal cells, and the A subunit entering the cells, resulting in the cellular changes that lead to watery diarrhea. To inhibit the B subunit of cholera toxin from binding host mucosa, we explored candidate phytochemicals instead of synthetic molecules as drug agents by examining their binding behavior with ctxB using a molecular docking approach. The molecular docking, molecular dynamic simulations, and toxicity analyses identified two phytochemical compounds that have the potential to inhibit the mechanism of cholera toxin.
Hypersensitivity controlled by mir-9a modulates female receptivity ofDrosophila melanogaster
Authors: Zhang Xiaoli , Bagley Joshua A. , Huang Yongwen , Kim Woo Jae
Published: July 2024

FemaleDrosophila melanogasterundergo a complex behavioral transformation following mating, characterized by increased sensory sensitivity and altered reproductive behaviors. In this study, we investigated the role of miR-9a, a conserved microRNA, in regulating these post-mating changes. We found that miR-9a mutant females exhibited a hypersensitivity phenotype, with increased rejection of courting males, delayed onset of sexual receptivity, and abnormal mating termination behavior. This phenotype was associated with aberrant overgrowth of adult body wall sensory neurons, suggesting a link between neuronal hypersensitivity and reproductive behavior. To further elucidate the underlying mechanisms, we performed genetic interaction studies withsensandbru2, genes known to interact with miR-9a. We found that removing one copy ofsensorbru2in miR-9a mutant backgrounds rescued the female rejection phenotype and normalized neuronal morphology. This suggests that miR-9a regulates sensory neuron development and female receptivity by modulating the expression of target genes likesensandbru2. Our findings reveal a novel role for miR-9a in regulating sensory hypersensitivity and reproductive behaviors inDrosophila. This research provides valuable insights into the molecular mechanisms underlying post-mating behavioral adaptations and neural development. Additionally, our findings highlight the potential ofDrosophilaas a model organism for investigating the role of miR-9 family members in neuronal specification and function, with implications for understanding sensory processing and neural plasticity in other organisms.
The Small GTPase Rho5 – Yet Another Player in Yeast Glucose Signaling
Authors: Schweitzer Franziska , Bischof Linnet , Walter Stefan , Morris Silke , Schmitz Hans-Peter , Heinisch Jürgen J.
Published: July 2024

The small GTPase Rho5 has been shown to be involved in regulating the Baker’s yeast response to stress on the cell wall, high medium osmolarity, and reactive oxygen species. These stress conditions trigger a rapid translocation of Rho5 and its dimeric GDP/GTP exchange factor (GEF) to the mitochondrial surface, which was also observed upon glucose starvation. We here show thatrho5deletions affect carbohydrate metabolism both at the transcriptomic and the proteomic level, in addition to cell wall and mitochondrial composition. Epistasis analyses with deletion mutants in components of the three major yeast glucose signaling pathways indicate a primary role of Rho5 upstream of the Ras2 GTPase in cAMP-mediated protein kinase A signaling. We also observed an inhibitory role of Rho5 on respiratory capacity, which may be explained by its role in mitophagy.
Topological susceptibility and axion potential in two-flavor superconductive quark matter
Authors: Murgana Fabrizio , Castillo David E. Alvarez , Grunfeld Ana G. , Ruggieri Marco
Published: July 2024

We study the potential of the axion, a, of Quantum Chromodynamics, in the two-flavor color superconducting phase of cold and dense quark matter. We adopt a Nambu-Jona-Lasinio-like model. Our interaction contains two terms, one preserving and one breaking the U(1)A symmetry: the latter is responsible of the coupling of axions to quarks. We introduce two quark condensates, hL and hR, describing condensation for left-handed and right-handed quarks respectively; we then study the loci of the minima of the thermodynamic potential, Ω, in the (hL,hR) plane, noticing how the instanton-induced interaction favors condensation in the scalar channel when the θ angle, θ=a/fa, vanishes. Increasing θ we find a phase transition where the scalar condensate rotates into a pseudoscalar one. We present an analytical result for the topological susceptibility, χ, in the superconductive phase, which stands both at zero and at finite temperature. Finally, we compute the axion mass and its self-coupling. In particular, the axion mass ma is related to the full topological susceptibility via χ=ma2fa2; hence our result for χ gives an analytical result for ma in the superconductive phase of high-density Quantum Chromodynamics.

Published by the American Physical Society
2024
Thermodynamically Ideal Quantum State Inputs to Any Device
Authors: Riechers Paul M. , Gupta Chaitanya , Kolchinsky Artemy , Gu Mile
Published: July 2024

We investigate and ascertain the ideal inputs to any finite-time physical process. We demonstrate that the expectation values of entropy flow, heat, and work can all be determined via Hermitian observables of the initial state. These Hermitian operators encapsulate the breadth of behavior and the ideal inputs for common thermodynamic objectives. We show how to construct these Hermitian operators from measurements of thermodynamic output from a finite number of effectively arbitrary inputs. The behavior of a small number of test inputs thus determines the full range of thermodynamic behavior from all inputs. For any process, entropy flow, heat, and work can all be extremized by pure input states—eigenstates of the respective operators. In contrast, the input states that minimize entropy production or maximize the change in free energy are nonpure mixed states obtained from the operators as the solution of a convex-optimization problem. To attain these, we provide an easily implementable gradient-descent method on the manifold of density matrices, where an analytic solution yields a valid direction of descent at each iterative step. Ideal inputs within a limited domain, and their associated thermodynamic operators, are obtained with less effort. This allows analysis of ideal thermodynamic inputs within quantum subspaces of infinite-dimensional quantum systems; it also allows analysis of ideal inputs in the classical limit. Our examples illustrate the diversity of “ideal” inputs: distinct initial states minimize entropy production, extremize the change in free energy, and maximize work extraction.

Published by the American Physical Society
2024
Development and commissioning of a broadband online X-ray spectrometer for the SXFEL Facility
Authors: Yang Zhicheng , Zhang Ximing , Geng Heping , Chen Jiahua , Feng Chao , Liu Bo , Li Bin
Published: July 2024

A broadband online X-ray spectrometer has been designed and commissioned at the SUD beamline of the Shanghai Soft X-ray Free-Electron Laser Facility, which can deliver both SASE and seeded FEL pulses to user experiments, spanning the photon energy range of 50–620 eV. The resolving powers of the spectrometer calibrated via online measurement at 92 eV and 249 eV are ∼20000 and ∼15000, respectively, and the absolute photon energy is characterized by an electron time-of-flight spectrometer. The high energy resolution provided by the spectrometer can differentiate the fine structure in the FEL spectrum, to determine its pulse length.
Analysing student satisfaction with teaching strategies in vocational education
Authors: Noguera Ingrid , Quesada-Pallarès Carla , Sepúlveda-Parrini Paloma
Published: July 2024

Purpose

Pedagogical and digital innovation in vocational education training (VET) is scarce as well as research on the subject. The pandemic may have prompted a modernization of VET that needs to be examined with a focus on the main subjects: the students. The purpose of this paper is to analyse students' perspectives on henceforth VET pedagogies. We aim to investigate students' perspectives and satisfaction regarding the didactic strategies and teaching modalities they experience to inform further trends in VET.

Design/methodology/approach

A quantitative and cross-sectional study was conducted, gathering the views of 460 Catalan VET students through a questionnaire. Data were analysed descriptively and applying the generalised linear model (GLM) mediation model to address the specific aims detailed below.

Findings

The findings show that the most frequent and preferred teaching strategies are lecturing and active learning, while situated learning is found to be less frequent and preferred. Face-to-face is the preferred teaching mode for all teaching strategies. The internship modality does not affect students' satisfaction with teaching strategies, while the professional brunch does.

Research limitations/implications

The limited responses gathered and the impact of the pandemic on the students' views limit the widespread applicability of the results. Future work must collect data from a broader sample and within a context of normality to determine current pedagogies and the use of digital technologies in VET.

Originality/value

Literature on VET pedagogies is scarce, and little is known about the predictable boost that the pandemic gave to the digitalisation and pedagogical modernisation of VET. Our study sheds light on the shift towards combined teaching strategies with a particular focus on active learning.
University students' participation in campus-based events
Authors: Nutsugbodo Ricky Yao , Blankson-Stiles-Ocran Sarah , Osei Benjamin Appiah , Afful Bernadette Ekua Bedua , Kuuder Conrad-Joseph Wuleka , Alhassan Thelma Ziemah , Akogo Josiane , Obeng Esther , Agyiri Philomina Dansowaa , Amponsah Gifty Nancy
Published: July 2024

Purpose

This study examined university students’ participation in campus-based events (CBEs). Using the Stimulus-Organism-Response (SOR) theory, the study specifically assessed the effect of motivation on emotional attachment and experiential value and how these affect the satisfaction and subjective well-being of students.

Design/methodology/approach

An online questionnaire programmed using the Kobo toolbox was used to collect data from 840 CBE participants in August 2023. AMOS Graphics version 23 was used to establish the measurement and structural model to be validated and tested.

Findings

The study found that the organismic elements (emotional attachment and experiential value) significantly mediated stimulus (motivation) and response (satisfaction and subjective well-being). In all, the six hypotheses tested were significant.

Practical implications

The study’s findings suggest that CBE stakeholders must consider the underlying motivations of students, the emotional attachment, and experiential values likely to be derived when designing and organizing CBE activities, and use impactful advertising media to entice and arouse students’ interest in participating in CBEs.

Originality/value

The study contributes to the understanding of the factors that influence CBE participants’ satisfaction and subjective well-being. The study’s focus on motivation, emotional attachment, and experiential value provides insights into developing effective strategies for the events industry.
We’re all just looking at the stars; how behavioral economics helps us understand the barriers to education programming in Tanzania
Authors: King Simon , Gove Amber
Published: July 2024

Purpose

We’re all just looking at the stars; how behavioral economics helps us understand the barriers to education programming in Tanzania.

Design/methodology/approach

This article uses a qualitative approach to explore the behaviorally normed barriers to quality classroom instruction that contribute towards low learning outcomes. Themed text analysis was applied to qualitative secondary data from seventeen classroom observations and teacher interviews collected from low-performing schools in rural Tanzania.

Findings

It was found that teachers in poor-performing schools in Tanzania were focused on the delivery of curriculum and pedagogy, with a misplaced belief that their pupils were performing adequately. The study found no evidence of teacher resistance to change; instead, the teachers were content and often happy to implement the reading program, believing that teaching phonics-based instruction improved their teaching approach. Teachers sought confirmation of their quality instructional practice from convenient yet inaccurate sources that did not include effective pupil assessment.

Research limitations/implications

As a result of the chosen research approach, findings may lack generalizability.

Practical implications

While existing models of teacher change rely on logic and reason for decision-making, this paper provides evidence that teacher models of change are much more complex and irrational, aligned more closely with insights from behavioral economics (BE). Additionally, this paper justifies that traditional research frameworks that study what works provide an incomplete picture to support effective program improvement.

Originality/value

The application of behavioral economics to research and education programming focused on reducing the restraining forces rather than pushing incentives and other program components.