bluuebunny/crossref_metadata_2025 huggingface dataset:
Can malaria be eliminated? 15 years on
Authors: Liu Youjia , Richardson Sol
Published: January 2025

This commentary reflects on the ongoing challenges and strategies in malaria elimination, built on insights from Greenwood's 2009 commentary, alongside more recent publications and developments up to 2024. Many of the challenges and strategies discussed by Greenwood remain relevant today. Furthermore, several of Greenwood's predictions have proven accurate 15 years on. Despite significant global progress, malaria elimination faces its toughest challenge, particularly in high-transmission areas. As we confront tougher challenges in malaria elimination, it becomes clear that we must go beyond mere reliance on any single solution.
Mamastrovirus species are shaped by recombination and can be reliably distinguished in ORF1b genome region
Authors: Aleshina Yulia , Lukashev Alexander
Published: January 2025

Astroviruses are a diverse group of small non-enveloped positive sense single-stranded RNA viruses that infect animals and birds. More than half of all known genome sequences of mammalian astroviruses are not assigned to provisional species, and the biological mechanisms that could support segregation of astroviruses into species are not well understood. The systematic analysis of recombination in Mamastrovirus genomes available in GenBank was done to identify mechanisms providing genetic distinction between astroviruses. Recombination breakpoints were present in all Mamastrovirus genome regions, but occurred most commonly at the ORF1b/ORF2 junction. Recombination was ubiquitous within, but never between established and putative new species, and may be suggested as an additional species criterion. The current species criterion for the genus Mamastrovirus based on ORF2 amino acid sequence p-distances did not reliably distinguish several established species and was of limited use to identify distinct groups among unclassified astroviruses that were isolated recently, predominantly from cattle and pigs. A 17% nucleotide sequence distance cut-off in ORF1b fairly distinguished the established species and several groups among the unclassified viruses, providing better correspondence between phylogenetic grouping, reproductive isolation and the virus hosts. Sequence distance criteria (17% in nucleotide sequence of ORF1b and 25% in amino acid sequence of ORF2) and the recombination pattern corresponded fairly well as species criteria, but all had minor exclusions among mammalian astroviruses. A combination of these taxonomic criteria supported the established Mamastrovirus species and suggested redefining a few provisional species that were proposed earlier and introducing at least six novel species among recently submitted rat and bovine astroviruses.
Association between obesity and Bell’s palsy by combining Mendelian randomization and network pharmacology
Authors: Zhong Li , Jiang Wei , Liu Yan , Huang Juan
Published: January 2025

Background:

The issue of obesity has emerged as a significant global health challenge; nevertheless, the association between Bell’s palsy (BP) and obesity remains ambiguous. In this study, the Mendelian randomization (MR) approach was employed to investigate their relationship, while network pharmacology methods were utilized to unveil the underlying mechanisms.

Methods:

We utilized single nucleotide polymorphisms closely linked to obesity and BP as instrumental variables for the MR analysis. Four robust bidirectional MR analysis methods, namely inverse variance weighting (IVW), weighted median, weighted mode, and MR-Egger were employed to assess the association between obesity and BP. Additionally, sensitivity analysis was conducted to evaluate levels of heterogeneity, sensitivity, and stability. Furthermore, we identified therapeutic targets associated with obesity and BP. Subsequently, a protein–protein interaction network analysis was conducted. Finally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were employed to investigate potential mechanisms underlying the relationship between obesity and BP.

Results:

The IVW analysis demonstrated a significant positive correlation between obesity and BP (odds ratio [OR] = 1.267, 95% confidence interval [95% CI] = 1.049–1.530, P = .013). However, there was no evidence to suggest that BP increased the risk of obesity. Furthermore, network pharmacology analysis revealed that the 2 diseases shared a total of 712 common targets. GO enrichment analysis shows that this process mainly regulates chemical synaptic signal transmission by modulating receptor signaling factor activity, receptor ligand activity, etc. KEGG enrichment analysis shows that the EGFR/PI3K/Akt signaling pathway plays a significant role in this process.

Conclusion:

Our study findings suggest that obesity may increase the risk of BP, and its underlying mechanism may potentially involve regulating chemical synaptic transmission through the EFGR/PI3K/Akt signaling pathway.
Schwannoma in the lower inner quadrant of the right breast in a male patient: A rare case report
Authors: Chen Jingjing , Huang Yan , Liu Haofeng , Sun Yuanyuan , Liu Fufeng
Published: January 2025

Rationale:

Lower inner-quadrant breast schwannomas are exceedingly rare, with no reports of their occurrence in male patients in the literature. In this report, we describe a male patient with a schwannoma in the lower inner quadrant of the right breast.

Patient concerns:

A 26-year-old man presented at our hospital with a 6-month history of a lump in the right breast and reported pain in the area 3 days prior to presentation. Ultrasonography identified a 0.86 × 0.64 cm hypoechoic nodule 0.41 cm beneath the skin in the lower inner quadrant of the right breast. The nodule exhibited clear boundaries and uniform internal echogenicity with no signs of significant blood flow on color Doppler flow imaging. The patient was concerned that the nodule was benign or malignant.

Diagnoses:

Histopathological and immunohistochemical analyses after complete surgical excision confirmed that the lesion was breast schwannoma. The postoperative course was unremarkable and the tumor did not recur during 7 years of follow-up.

Interventions:

Biochemical parameters were examined preoperatively. The radiological examination of breast color Doppler ultrasound was performed.

Outcomes:

A well-shaped, 0.86 × 0.64 cm mass, complete capsule in the lower inner quadrant of the right breast was surgically resected. The postoperative course was unremarkable and the tumor did not recur during 7 years of follow-up.

Lessons:

Breast schwannoma is an extremely rare tumor that is very difficult to preoperatively diagnose. Preoperative biochemical examination and ultrasonography can only provide diagnostic ideas. Histological and immunohistochemical analyses are required for confirmation. It can transform into malignant peripheral nerve sheath tumors, but not often. Consequently, regular postoperative follow-up is required for such patients, especially ultrasonography.
High-dose methotrexate-based chemotherapy for induction remission of newly diagnosed primary CNS lymphoma: A systematic review and meta-analysis
Authors: Shi Han , Sun Xuefei , Wu Yuchen , Cui Qu , Sun Shengjun , Ji Nan , Liu Yuanbo
Published: January 2025

Background:

This study aimed to comprehensively assess the optimal regimen for high-dose methotrexate (HD-MTX) in treating primary central nervous system lymphoma (PCNSL).

Methods:

We have searched 8 databases, including PubMed, EMBASE, Cochrane Library, WOS, Epistemonikos, CNKI, WAN-FANG Database, and CBM, and were selected for the clinical trials about PCNSL. A total of 37 studies were included in our analysis, consisting of 6 randomized controlled trials and 31 single-arm clinical studies.

Results:

After analyzing the data from 37 clinical studies, we found that the pooled overall response rate (ORR) for low-dose (<3 g/m2), medium-dose (3–5 g/m2), and high-dose (>5 g/m2) methotrexate (MTX) were 0.78, 0.80, and 0.80, respectively. The pooled 2-year overall survival (OS) for low-dose, medium-dose, and high-dose MTX were 52%, 60%, and 71%, respectively. The ORR, complete response (CR), and 2-year OS of patients who received <5 cycles of MTX were 79%, 41%, and 59%, respectively, whereas those for PCNSL patients who received >5 cycles of MTX were 81%, 54%, and 64%, respectively. The pooled ORR for MTX, dual therapy, triplet therapy, tetrad therapy, and multiple therapy were 71%, 70%, 81%, 85%, and 80%, respectively. The pooled 2-year OS for different numbers of medication combinations were 59%, 52%, 66%, 63%, and 60%, respectively. The addition of cytarabine to MTX-based chemotherapy resulted in higher CR, although no statistically significant difference was observed in OS. Adding rituximab to the treatment regimen improved patients’ progression-free survival without affecting treatment response or OS.

Conclusion:

Based on the findings of this study, the treatment strategies of MTX are associated with the prognosis and efficacy response of PCNSL patients. The results suggested that the current recommended HD-MTX dosage of 3.5 g/m2 is sufficient for PCNSL to have a favorable treatment response and prognosis. When the number of MTX treatment cycles increases, the therapeutic effect and prognosis of PCNSL patients are improved. The patients treated with MTX-based triplet combination regimens have a better ORR and CR. Although HD-MTX is generally well tolerated, it is necessary to be cautious about the use of multiple therapy that includes cytarabine to prevent potential acute toxicity.
Kidney and pregnancy outcomes in pregnancy-associated atypical hemolytic uremic syndrome: A systematic review and meta-analysis
Authors: Meena Priti , Gala Ruju , Das Rashmi Ranjan , Bhargava Vinant , Saivani Yellampalli , Panda Sandip , Mantri Alok , Agrawaal Krishna Kumar
Published: January 2025

Background:

Pregnancy-associated atypical hemolytic uremic syndrome (p-aHUS) is a rare, life-threatening condition characterized by microangiopathic hemolytic anemia, thrombocytopenia, elevated liver enzymes, and acute kidney injury. Prompt diagnosis and therapy are crucial due to the high risk of progression to chronic kidney disease (CKD), end-stage kidney disease (ESKD), and dialysis dependency, as well as significant maternal and fetal morbidity and mortality.

Methods:

A comprehensive literature search was conducted across EMBASE, MEDLINE, and the Cochrane CENTRAL from January 2000 to March 2024. Studies reporting on pregnancy and kidney outcomes in women diagnosed with p-aHUS were included.

Results:

Ten studies involving 386 pregnancies in 380 patients met the inclusion criteria for the final analysis. Renal outcomes varied, with mean creatinine levels ranging from 0.72 to 8.734 mg/dL. Dialysis was required in 66.6% of patients, and 25% developed ESKD. Maternal complications included preeclampsia (36.4%) and hemolysis, elevated liver enzymes, and low platelets syndrome (29.7%), with a 5% maternal mortality rate. Fetal complications included intrauterine fetal demise (n = 25), intrauterine growth restriction, low birth weight, and prematurity. Treatment with eculizumab significantly reduced the risk of CKD and ESKD, with a pooled risk ratio of 0.20 (95% confidence interval: 0.09–0.44) and low heterogeneity (I² = 0%, P = .43).

Conclusion:

This analysis highlights the severe kidney and pregnancy outcomes associated with p-aHUS. Eculizumab treatment is significantly beneficial in reducing the risk of CKD and ESKD.
Septic cardiomyopathy or myocardial infarction?: A case report of septic shock with ST-segment elevation on ECG
Authors: Gao Haolei , Wang Xiaodong , Yang Qingyue
Published: January 2025

Rationale:

Sepsis is one of the most prevalent and deadly diseases today. Sepsis involving the heart can progress to septic cardiomyopathy; however, there is a lack of uniform diagnostic criteria. A review of the literature reveals a paucity of literature on sepsis combined with acute myocardial infarction (AMI) and no reports on emergency surgical treatment.

Patient’s concerns:

A 52-year-old patient with trauma-induced sepsis leading to acute heart failure with elevated ST-segment on electrocardiogram and postoperative coronary angiography suggestive of AMI.

Diagnoses:

Small bowel rupture, infectious shock, AMI, hypertensive disease, old cerebral infarction.

Interventions:

The patient was admitted to the hospital and immediately underwent emergency surgery to remove the infected focus, with treatment with meropenem for anti-infection, ambroxol for sputum, parenteral nutritional support, sedation and analgesia, esmolol to control the ventricular rate, uradil to control blood pressure, and transfusion of red blood cells and plasma for correction of anemia and coagulation functions. Coronary angiography was performed 6 months later.

Outcomes:

The patient was discharged after showing signs of improvement and was subsequently monitored in an outpatient clinic setting. At the time of writing, the patient is still alive and well.

Lessons:

In cases of acute heart failure resulting from trauma-induced sepsis, it is crucial to consider myocardial ischemia as a potential factor. Early surgical removal of infected foci may prove beneficial in improving the patient’s prognosis. However, differentiating between septic cardiomyopathy and sepsis-combined myocardial infarction can be challenging, and the appropriateness of the diagnostic criteria for sepsis at this stage is debatable.
Evaluation of the Education & Outreach Symposium at the Microbiology Society Annual Conference 2024
Authors: Lacey Melissa M , Dillon Michael J , Goodman Sean , Easton Victoria , Graham Alison I
Published: January 2025

The Microbiology Society Education & Outreach Symposium serves as a platform for microbiology educators to share contemporary practices with an international audience.  The Symposium is held yearly during the Microbiology Society’s Annual Conference and has become increasingly popular amongst conference attendees.  In an effort to create an inclusive and engaging environment, the 2024 Symposium included contributions from participants at all career stages and from diverse global regions through a variety of presentation formats, including invited talks, offered presentations, flash talks, and posters.  Cabaret-style seating was used to encourage discussion amongst participants and digital tools were used for anonymous feedback and questions after each talk to ensure all voices had an opportunity to be heard.  Here we present an analysis of qualitative and quantitative participant responses addressing two key research questions: 1) Did the Symposium foster an inclusive atmosphere for participants across all career stages? and 2) Was the content engaging and relevant to the audience?  A post-Symposium questionnaire revealed strong positive feedback, with all 18 respondents agreeing or strongly agreeing that the 2024 Symposium was both an inclusive environment and covered interesting topics.  Thematic content analysis of free-text responses emphasised a high appreciation for the Symposium’s diversity in speakers and topics, an inclusive room layout, and overall welcoming feeling.  Feedback from participants will actively feed into planning for the 2025 Symposium.
The calculation of the mutation frequency for humans at different proton doses in a mathematical model and estimation of the mutation risks for the space explorations
Authors: Kara Metehan , Demirköz Melahat Bilge
Published: January 2025

DNA is considered a fundamental component of life, yet it remains vulnerable to damage under extreme conditions, such as ionizing radiation exposure. To better understand this fragility, it becomes important to estimate mutation frequencies under different radiation doses. Furthermore, this approach has potential for future applications, especially in the context of deep space exploration, where astronauts are exposed to higher levels of cosmic radiation. For this purpose, we developed a mathematical model by integrating two existing models, the Monte Carlo Excision Repair (MCER) model and the Whack-a-Mole (WAM) model, both specifically adapted for use in manned space missions. The WAM model is supported with the Monte Carlo simulation to address the lack of human experimental data available in previous studies so that by calculating four key variables related to the human cells defined in the WAM model, potential mutations in astronauts during space exploration were estimated. The results showed small deviations from previous studies, which can be attributed to differences in the type of radiation sources as well as the organisms studied being different from those used in previous studies. With this study, researchers can now better predict mutation frequency during deep space missions by considering the impact of cosmic radiation. This is particularly important in the context of future missions to the Moon and Mars, where cosmic radiation will play an important role in mission planning and risk management.
A pathological phosphorylation pattern enhances tau cooperativity on microtubules and facilitates tau filament assembly
Authors: Fan Xiangyu , Okada Kyoko , Lin Henry , Ori-McKenney Kassandra M. , McKenney Richard J.
Published: January 2025

Phosphorylation plays a crucial role in both normal and disease processes involving the microtubule-associated protein tau. Physiologically, phosphorylation regulates tau’s subcellular localization within neurons and is involved in fetal development and animal hibernation. However, abnormal phosphorylation of tau is linked to the formation of neurofibrillary tangles (NFTs) in various human tauopathies. Interestingly, the patterns of tau phosphorylation are similar in both normal and abnormal processes, leaving unclear whether phosphorylated tau retains its functional role in normal processes. The relationship between tau phosphorylation and NFT assembly in tauopathies is also still debated. To address these questions, we investigated the effects of tau phosphorylation on microtubule binding, cooperative protein envelope formation, and NFT filament assembly relevant to tauopathies. Consistent with previous results, our findings show that tau phosphorylation decreases tau’s overall affinity for microtubules, but we reveal that phosphorylation more dramatically impacts the cooperativity between tau molecules during tau envelope formation along microtubules. Additionally, we observed that the specific pattern of phosphorylation, rather than overall phosphorylation level, strongly impacts the assembly of tau filamentsin vitro. Our results reveal new insights into how tau phosphorylation impacts tau’s physiological roles on microtubules and its pathoconversion into NFTs.
Neural correlates of memory updating in the primate prefrontal cortex
Authors: Sawagashira Ryo , Tanaka Masaki
Published: January 2025

Working memory is the ability to temporarily hold and manipulate information during cognitive tasks and is essential for complex behaviors and thinking. Although the primate lateral prefrontal cortex is involved in working memory and the neural representation of short-term memory has been reported, little is known about neuronal activity during memory updating. We trained macaque monkeys to perform an oculomotor version of the n-back task, in which the animals were required to remember the location of serially presented visual stimuli and generate a saccade to the location of the most recent or previous stimulus according to the instructions. We found that many neurons in the lateral prefrontal cortex showed transient activity when the memory of a particular stimulus location was no longer needed, whereas other neurons showed sustained activity when the stimulus location was maintained in memory. Decoding analysis successfully predicted future target selection from neuronal activity, indicating that these neuronal populations contain sufficient information to guide behavior. Furthermore, electrical stimulation applied to recording sites during the task erased specific spatial memories, suggesting that these neurons are causally involved in the retention of short-term memories and their dynamic control.
Measuring bridging forces in protein-DNA condensates
Authors: Ahlawat Vikhyaat , Mudiyanselage Hashini Ekanayake , Zhou Huan-Xiang
Published: January 2025

Protein-DNA condensates mediate transcription and regulate gene expression and DNA replication and repair. The intermolecular bridging forces stabilizing condensates have direct roles in these processes. Here we use optical tweezers to measure bridging forces. In the presence of protamine, a single condensate is observed on a 20.5-knt single-stranded DNA (ssDNA) tethered between two microbeads. Stretching produces force curves with a sawtooth pattern, suggesting that the condensate is dissembled by the sequential rupture of individual protamine-ssDNA bridges. The bridging forces are 11.3 ± 4.6 pN, with unfolding lengths of 1.3 ± 0.8 µm for single bridges. In contrast, double-stranded DNA (dsDNA) forms protamine-bridged tangles that can withstand forces high enough (∼55 pN) for strand separation. ssDNA tracks unpeeled at nicks on dsDNA by overstretching seed tangle formation upon retraction, but the initial condensates have a sufficient ssDNA-to-dsDNA ratio to appear liquid-like, as indicated by a sawtooth pattern in the subsequent stretching. The presence of dsDNA raises bridging forces to 34 ± 8 pN, which revert to ∼10 pN upon adding external ssDNA. In line with these single-molecule results, protamine-dsDNA mixtures form solid-like aggregates and require the addition of ssDNA to become liquid droplets. Conversely, adding dsDNA slows the fusion of protamine-ssDNA droplets. This work demonstrates the first measurements of bridging forces and shows that the ssDNA-to-dsDNA ratio can tune their magnitude in protein-DNA condensates.
Pectobacterium versatile beta-lactamase, a common good of the soft rot Pectobacteriaceae species complex
Authors: Lorang Camille , Canto Pierre-Yves , Gueguen Erwan , Pedron Jacques , Barny Marie-Anne
Published: January 2025

Little is known about the role of antibiotics and associated resistance in microbial ecosystems in the absence of clinical antibiotic pressure. The Soft Rot Pectobacteriaceae (SRP) species complex, which comprises 37 bacterial species that are collectively responsible for the severe rotting of many crops, is an interesting model to analyse the role of β-lactam and β-lactamases in natural ecosystems. In particular, within this complex, most Pectobacterium versatile strains harbour a β-lactamase called BlaPEC-1. The aim of our work was to analyse the role of BlaPEC-1 during infection. To this end, two blaPEC-1-deleted strains were constructed and compared with their wild-type counterparts in vitro and in potato tuber infections. In vitro, the BlaPEC-1 β-lactamase enables P. versatile to resist ampicillin or carbapenem produced by Pectobacterium brasiliense. In mono-infections on potato tubers, blaPEC-1-deleted strains were unaffected in terms of virulence, fitness or association with commensal bacteria. In mixed infections, the BlaPEC-1 β-lactamase proved necessary for the coexistence of P. versatile with the carbapenem-producing strain, and also for the protection of carbapenem-sensitive strains both in vitro and in planta. Interestingly, in planta protection was observed even if the blaPEC-1 gene was repressed and bacteria expressing BlaPEC-1 were in the minority within the symptom. These results indicate that BlaPEC-1 exerts a true β-lactamase function during the infection process and acts as a public good of the SRP species complex. Finally, our results highlight the important role of β-lactamase in maintaining of strains diversity in natural ecosystem.
Emergence of multiple collective motility modes in a physical model of cell chains
Authors: Zhang Ying , Bastounis Effie E. , Copos Calina
Published: January 2025

Collective cell migration underpins key (patho)physiological processes, ranging from embryonic development to wound healing and cancer metastasis. While notable progress has been made in elucidating mechanisms that drive collective cell motility, the classification remains incomplete. In this study, we focus on the migration patterns of small cell chains, specifically cohesive pairs of cells migrating after each other on flat surfaces. Experiments withDictyostelium discoideum(Dd) cells, which typically display amoeboid motility, revealed two distinct motility modes in cell pairs: the individual contributor (IC) mode, where each cell generates its own traction force dipole, and the supracellular (S) mode, characterized by a single dipole. Intriguingly, the IC mode dominates in Dd pairs, but the S mode prevails in Madin-Darby canine kidney (MDCK) cell doublets, which typically undergo mesenchymal motility. This observation highlights an apparent discrepancy in emergent motility modes between cell types. To uncover the physical mechanisms driving these diverse motility modes, we developed a two-dimensional biophysical model incorporating mechanochemical details such as cell-cell adhesion, combined with membrane-cortex contractility, and cell-matrix adhesion. Our model could recapitulate many experimental observations; the IC mode emerged naturally in amoeboid doublets when both cells exerted similar traction stresses, while the S mode dominated with “stronger” leaders that essentially pull on trailers. In contrast, in our simulations, mesenchymal MDCK-like pairs largely migrated in supracellular arrangement (S mode), with traction stress patterns representative of a rear-drive system with a “pushy” trailer, rather than a front-drive system. Our findings also showed that increasing cell-matrix adhesion predisposes amoeboid cell chains to act autonomously (IC mode), but the chain’s motility mode was largely insensitive to changes in cell-cell adhesion parameters. Contrary to amoebas, MDCK-like cell chains showed a bias towards S mode when increasing cell-matrix adhesion and a preference on IC mode when increasing cell-cell adhesion. Extending the model to longer cell chains, we showcase the model’s applicability across scales, providing a foundation for exploring collective migratory behavior in other contexts.
Synaptic Targets of Circadian Clock Neurons Influence Core Clock Parameters
Authors: Scholz-Carlson Eva , Iyer Aishwarya Ramakrishnan , Nern Aljoscha , Ewer John , Fernandez Maria Paz
Published: January 2025

Neuronal connectivity in the circadian clock network is essential for robust endogenous timekeeping. In the Drosophila circadian clock network, the four pairs of small ventral lateral neurons (sLNvs) serve as main pacemakers. Peptidergic communication via sLNv, which release the key output neuropeptide, Pigment Dispersing Factor (PDF), has been well characterized. In the absence of PDF, flies become largely arrhythmic, similar to the phenotype associated with the loss of the mammalian circadian peptide, VIP. In contrast, little is known about the role of the synaptic connections that sLNvs form with downstream neurons. Connectomic analyses revealed that despite their role as key pacemaker neurons within the clock network, the sLNvs form very few monosynaptic connections with other clock neurons. However, they form strong synaptic connections with a small group of previously uncharacterized neurons, SLP316, which in turn synapse onto dorsal clock neurons. Here, we show that silencing SLP316 neurons via tetanus toxin (TNT) expression shortens the free-running period, whereas hyper-exciting them by expressing the constitutively open Na[+] channel, NaChBac, results in period lengthening. Under light-dark cycles, silencing SLP316 neurons also causes lower daytime activity and higher daytime sleep, likely due to increased sleep pressure. Our results revealed that the main postsynaptic partners of the Drosophila pacemaker neurons are a non-clock neuronal cell type that regulates the timing of sleep and activity.
Plasticity and invariance of Arabidopsis inflorescence and floral shoot apical meristems in response to mineral nutrients
Authors: Landrein Benoit , Abley Katie , Formosa-Jordan Pau , Meyerowitz Elliot M. , Jönsson Henrik , Locke James C. W.
Published: January 2025

In many species, floral organ production is invariant while flower production rate can be plastic. This allows plants to adapt flower number to their environment whilst maintaining a constant flower structure. TheCLAVATA/WUSCHELfeedback loop underpins both inflorescence (IM) and floral meristem (FM) activity, respectively responsible for flower and floral organ production. We explore how plasticity and invariance can differ between IM and FM in response to nutrient availability. FM size is less sensitive to changes in nutrients than IM size, and floral organ production is insensitive to these small size changes. However,clavata3mutants display larger changes in FM size, approaching those observed in WT IM under nutrient change, with increased floral organ number. This suggests that invariant floral organ production requires that FM size undergoes limited changes in response to nutrients. Compared to the IM, in the FM, levels of cytokinin (CK) signaling are lower and CK signaling andWUSCHELexpression are less impacted by nutrient level. Through genetic perturbations, we show a reduced response of FMs to varying cytokinin levels. Our work shows one way that the balance between plasticity and invariance can be set differently in different contexts.
Arp2/3-mediated bidirectional actin assembly by SPIN90 dimers in metazoans
Authors: Liu Tianyang , Cao Luyan , Mladenov Miroslav , Romet-Lemonne Guillaume , Way Michael , Moores Carolyn A.
Published: January 2025

Branched actin networks nucleated by the Arp2/3 complex play critical roles in various cellular processes, from cell migration to intracellular transport. However, when activated by WISH/DIP/SPIN90 family proteins, Arp2/3 nucleates linear actin filaments. Unexpectedly, we found that human SPIN90 is a dimer that can nucleate bidirectional actin filaments. To understand the basis for this, we determined a 3 Å resolution structure of human SPIN90-Arp2/3 complex nucleating actin filaments. Our structure shows that SPIN90 dimerises via a 3-helix bundle and interacts with two Arp2/3 complexes. Each SPIN90 molecule binds both Arp2/3 complexes to promote their activation. Our analysis demonstrates that single filament nucleation by Arp2/3 is mechanistically more like branch formation than previously appreciated. The dimerisation domain in SPIN90 orthologues is conserved in metazoans, suggesting that this mode of bidirectional nucleation is a common strategy to generate anti-parallel actin filaments.
Insights into adhesive and neuronal cell populations of the chaetognathSpadella cephalopterausing a single-nuclei transcriptomic atlas and genomic resources
Authors: Barrera Grijalba Cristian Camilo , Ordoñez June F , Montenegro Juan , Wollesen Tim
Published: January 2025

To cope with extreme environmental conditions diverse marine species have developed mechanisms that allow them to permanently or temporarily attach to substrates. In the intertidal zone of marine habitats, where tidal ranges and currents may drift organisms away from their habitat, temporary adhesive systems such as the one inherent the arrow wormSpadella cephaloptera(Chaetognatha) constitute an essential trait for the survival of this taxon. The underlying molecular mechanism of this system has not been described yet, and the existing morphological information is limited to adults. Furthermore, a relationship between the nervous system and the attachment inS. cephalopteraremains to be demonstrated. In this study, single-nuclei sequencing ofS. cephalopterahatchlings was performed, using as a reference a newly sequenced and assembled genome to identify the transcriptomic profiles of the cells mediating attachment, neuronal populations, and the main cell types of chaetognath hatchlings. Our findings, supported by previous studies, suggest that the chaetognath adhesive system evolved convergently to those of other other metazoans. Moreover, diverse cell types were identified in the ventral nerve center and multiple ciliated cell types previously described from anatomical observations were validated. Ongoing in-depth investigation of these data, together with datasets from other developmental stages, will provide further insights into the evolutionary origins of the unique chaetognath body plan.
Measuring the Burgers vector of dislocations with dark-field X-ray microscopy
Authors: Pal Dayeeta , Wang Yifan , Gurunathan Ramya , Dresselhaus-Marais Leora
Published: January 2025

The subsurface dynamics of dislocations are essential to many properties of bulk crystalline materials. However, it is challenging to characterize a bulk crystal by conventional transmission electron microscopy (TEM) due to the limited penetration depth of electrons. A novel X-ray imaging technique – dark-field X-ray microscopy (DFXM) – was developed to image hierarchical dislocation structures in bulk crystals. While today's DFXM can effectively map the line structures of dislocations, it is still challenging to quantify the Burgers vectors, the key characterization governing the dislocation behaviors. We extend the `invisibility criterion' formalism from the TEM theory to the geometrical-optics model of DFXM and demonstrate the consistency between DFXM and dark-field TEM using multi-diffraction-peak imaging for a single edge dislocation. Due to the practical difficulty of multi-peak DFXM experiments, we further study how the Burgers vector effect is encoded for a single-peak DFXM experiment. Using the geometrical-optics DFXM simulation, we explore the asymmetry of rocking tilt scans at different rolling tilts and develop a new method to characterize the Burgers vector. The conclusions of this study advance our understanding of the use of DFXM in characterizing individual dislocations, enabling the connection from bulk DFXM imaging to dislocation mechanics.
New robotic tools for multimodal non-destructive analysis and characterization of 2D and 3D objects
Authors: Kotrlý Marek , Uher Josef , Jakubek Jan , Skála Roman , Boháčová Jana , Turková Ivana , Starkbaumová Kamila
Published: January 2025

The forensic field has until now been missing more versatile equipment for non-destructive characterization, analysis and inspection of 2D and 3D objects. Also, the need for increasingly frequent analysis of art forgeries, where non-destructive analysis is required at least in the first step, is calling for a multimodal solution. A prototype device for robotic analysis, imaging and mapping of 3D objects is being developed and tested to be used in these areas. The system is based on the principle of integrating imaging and analytical technologies onto six-axis robotic arms, which allow substantial flexibility in the sample size or shape. The system enables non-destructive examination of a wide spectrum of samples with complicated curvatures. The new generation of X-ray imaging detectors provide a high picture quality with a spatial resolution level in the micrometre range in 2D or 3D imaging. The basic version of the robotic scanner allows transmission X-ray imaging and mapping of the individual photons with high-sensitivity and high-resolution detectors. The broad capabilities of XRD imaging are now being complemented by X-ray fluorescence point analysis and mapping, multispectral macro imaging, and multispectral X-ray diffraction analysis.
Numerical study of current distribution under high-velocity in railgun with moving boundary conditions
Authors: Xu Jinghan , Xia Shengguo , Chen Lixue , Gu Anbang , Yang Hongdan , Li Chengxian
Published: January 2025

Purpose

The purpose of this paper is to investigate the moving boundary conditions on the sliding armature and rail (A/R) interface. As the computational domains involve both moving and stationary conductors, Lagrangian description and backward difference schemes are adopted for spatial and temporal discretization, arising discontinuities in variables. The proposed formulation can compute the current distribution under high velocities (∼km/s) without numerical oscillations and avoids mesh re-generation, saving computational resources.

Design/methodology/approach

The governing equations in Lagrangian description, backward difference schemes and derivations of moving boundary conditions are shown in detail. The interface matrix is explicitly enforced on the whole domain matrix and pseudocodes are presented for implementation. Moreover, shifted interpolated quantity method is proposed to deal with unevenly sized mesh, which can calculate acceleration scenarios and save computation resources under high velocities. Comparative calculations with previous methods under low velocities are conducted to verify the correctness of computational and physical models.

Findings

The current distributions with constant velocities are consistent with previous two-dimensional and low-velocity studies, further verifying the correctness of the method. The three-dimensional high-velocity results show that the current tends to concentrate near the trailing edge of A/R interface and diffuses into the bulks over time, with higher velocity contributing to less significant current diffusion. The velocity skin effect precedes the magnetic diffusion, conductivity and other factors that influence the current distribution.

Originality/value

The proposed methods can compute the current distributions in railgun under velocity accelerated to over 2,000 m/s, and the results provide more comprehensive understandings of the current evolution process under velocity skin effect in railgun.
Lemon Tree Hotels: decisions at the intersection of ownership and asset-light strategies
Authors: Laddha Seema , Iyer Kamatchi
Published: January 2025

Learning outcomes

The case study aims to facilitate a deep understanding of the strategic decisions in the context of asset-light model, its competitive advantage and industry dynamics within the context of the Indian hospitality sector. Suggested teaching objectives for the case study are as follows:▪ Analyze the strategic decisions made by Lemon Tree Hotels in the context of the Indian hospitality industry.▪ Evaluate the challenges and opportunities associated with the transition from an ownership-centric model to an asset-light strategy.▪ Discuss the competitive advantage built by Lemon Tree Hotels and the implications of its unique market offering.▪ Explore the impact of the post-pandemic era on the hospitality sector and the strategic adjustments made by the company.▪ Encourage critical thinking about the future trajectory of Lemon Tree Hotels, considering the ownership dilemma and evolving market dynamics.

Case overview/synopsis

The case study explores the strategic decisions made by Lemon Tree Hotels, a mid-market hotel chain in India, at the intersection of ownership and asset-light strategies. The founder, Patanjali Keswani, faced a dilemma of whether to persist with the ownership-centric model that propelled the company’s success or to pivot toward an asset-light approach, acknowledging the capital-intensive nature inherent in the industry. The case delves into the complexities of expansion, the adoption of an asset-light model and the challenges and opportunities encountered. Keswani’s calculated decisions and the company’s unique offering established its competitive edge. However, the shift to an asset-light model raised questions about the sustainability of this advantage in the more competitive mid-segment hospitality sector. The case discusses the challenges in the mid-market hotel industry in India, the transformative changes in consumer expectations and the strategic significance of the company’s transition to an asset-light model. The narrative unfolds through a lens that considers the competitive advantage built on a positive brand image, operational efficiency and a unique market offering. The case concludes at a strategic juncture, leaving Keswani and Lemon Tree Hotels grappling with the dilemma of ownership versus asset-light strategies, with implications for the company’s future trajectory.

Complexity academic level

The case study is designed for postgraduate students studying management, business administration and strategic management.

Supplementary material

Teaching notes are available for educators only.

Subject code

CSS11: Strategy.
Artificial neural networks for flood susceptibility analysis in Gangarampur sub-division of Dakshin Dinajpur, West Bengal, India
Authors: Paul Asit
Published: January 2025

Purpose

The study aims to identify the areas of flood susceptibility and to categorize the Gangarampur sub-division into various flood susceptibility zones. It also aspires to evaluate the efficacy of integrating Geographic Information Systems (GIS) with Artificial Neural Networks (ANN) for flood susceptibility analysis.

Design/methodology/approach

The factors contributing to floods such as rainfall, geomorphology, geo-hazard, elevation, stream density, land use and land cover, slope, distance from roads, Normalized Difference Water Index (NDWI) and distance from rivers were analyzed for flood susceptibility analysis. The use of the ANN model helps to construct the flood susceptibility map of the study area. For validating the outcome, the Receiver Operating Characteristic (ROC) is employed.

Findings

The results indicated that proximity to rivers, rainfall deviation, land use and land cover are the most significant factors influencing flood occurrence in the study area. The ANN model demonstrated a prediction accuracy of 85%, validating its effectiveness for flood susceptibility analysis.

Originality/value

The research offers a novel approach by integrating Geographic Information Systems (GIS) with Artificial Neural Networks (ANN) for flood susceptibility analysis in the Gangarampur sub-division. By identifying key factors such as proximity to rivers, rainfall deviation and land use, the study achieves 85% prediction accuracy, showing the effectiveness of ANN in flood risk mapping. These findings provide critical insights for planners to devise targeted flood mitigation strategies.
Enhancing teachers’ creative teaching through transformational leadership within a diverse workplace: the role of principals’ cross-cultural competence, and teachers’ task independence and promotion focus
Authors: Tang Chia Wei
Published: January 2025

Purpose

Drawing on concepts from workplace diversity and cognitive evaluation theories (CETs), this study seeks to deepen our understanding of the link between transformational leadership and teachers’ creative teaching in a more and more diverse campus.

Design/methodology/approach

Survey data involving a total of 895 high school teachers across Taiwan were collected using purposive sampling methodology and analysed with SPSS and SmartPLS software.

Findings

The results reveal that the positive relationship between the principal’s transformational leadership and teachers’ creative teaching is partially mediated by teachers’ promotion focus and task interdependence which could reduce the defensive silence and reluctant collaboration found in diverse workplaces. Moreover, principals’ cross-cultural competence also moderates such relationship, since it helps transformational leader to take adaptive measures to address the challenges associated with managing differences in perspective and ideas within a heterogeneous workforce. Based on these findings, implication for educational leadership is discussed.

Originality/value

Studies have affirmed the positive association between transformational leadership and creative teaching. However, the mechanism sustaining this relationship and how this relationship can further be intensified are still unknown, especially in a more and more diverse education context. Our analysis shows that principals’ cross-cultural competence, and teachers’ task independence and promotion focus are relevant factors school leaders should consider in enhancing the link between their transformational leadership and teachers' creative teaching.
Servant leadership and employee creativity in Islamic context: role of employee empowerment and knowledge sharing
Authors: Alasmari Saad , Ali Anees Janee , Khalid Jamshed , Chuanmin Mi , Rasheed Muhammad Shahid
Published: January 2025

Purpose

In today’s volatile global marketplace, cultivating human capital via efficient leadership has become an indispensable requisite for organizational growth. This study aims to examine how servant leadership affects employee creativity through employee empowerment. Moreover, this study examines the moderating effect of knowledge sharing in the relationship between employee empowerment and employee creativity.

Design/methodology/approach

Quantitative data were processed using Smart PLS-SEM to test the hypothesis. Survey data for this study were obtained from 368 employees working in two Islamic holy sites: the Masjid al-Haram and the Masjid an-Nabawi.

Findings

A positive correlation is found between employee empowerment and employee creativity. In addition, employee empowerment mediates the relationship between servant leadership and employee creativity. Lastly, knowledge sharing moderates the effect of employee empowerment on employee creativity.

Practical implications

The findings shed light on the need for servant leadership in service sector organizations. The findings imply that employee creativity in religious firms can be promoted by servant leadership. The results of this study can assist managers in developing a deeper understanding of contextual factors such as employee empowerment and knowledge sharing while formulating policies and development plans.

Originality/value

The impact of servant leadership in fostering creativity within religious organizations has not been investigated sufficiently. This study expands the literature by offering a thorough understanding of the contextual factors influencing employee creativity in religious organizations such as the mediating role of employee empowerment and the moderating role of knowledge sharing.
The potential of digital-based technology in improving organizational performance
Authors: Odebode Adedayo Ayodeji , Ogunbayo Oyeronke Toyin
Published: January 2025

Purpose

The growing concern with the rapid evolution in adopting emerging technologies in the real estate industry to enhance performance is a threat to conventional practice. The paper aims to examine the latent influence of digital-based technology on employees toward improving organizational performance.

Design/methodology/approach

The study employed an exploratory research design. The study sampled 132 real estate firms in Lagos State, Nigeria. The study adopts a random sampling method, and only 87 questionnaires were retrieved and found suitable for analysis. The data were analyzed using descriptive and inferential statistics.

Findings

The study perceived that the adoption of digital-based tools enhances employee creativity and usage, work ethics, decision-making skills, behaviors and traits toward business performance. Furthermore, firm culture, training and development, assessment of employee productivity metrics, the firm’s expectations and strategic technology applications are significant factors that impact employee decisions to drive organizational performance.

Practical implications

The study has an implication for the real estate industry in a achieving technology-based performance system by involving employees’ in attaining overall organizational business objectives.

Originality/value

The paper is relevant because it examines the empirical study of the influence of digital technologies in enhancing employee performance with the goal of enhancing the organization’s competitiveness while maintaining flexible approaches to withstand future business risk and uncertainty.