bluuebunny/crossref_metadata_2025 huggingface dataset:
A computational Evo-Devo approach for elucidating the roles of PLETHORA transcription factors in regulating root development
Authors: Rodríguez Herrera Joel , Galván Alcaraz Kenia Aislinn , Albarrán Hernández Ramsés Uriel , Villa Núñez Juan Pablo , Rodríguez Alonso Gustavo , Shishkova Svetlana
Published: December 2024

PLETHORA (PLT) transcription factors play essential roles in regulating various developmental processes in plants, including embryogenesis, rhizotaxis, phyllotaxis, and most prominently, root development, by regulating cell proliferation and differentiation along the root. Despite their important roles in plant development, PLT transcription factors have mainly been studied inArabidopsis thalianaand only a few crop species.A. thalianahas sixPLTgenes, which are expressed in overlapping domains and have partially redundant activities, with numerous shared target genes. Here we identified putativePLTorthologs across Viridiplantae, including representatives of all extant plant clades, reconstructing the molecular phylogeny of PLTs and integrating synteny and microsynteny analyses. We suggest that PLTs arose by neofunctionalization prior to the divergence of Spermatophyta and that they might regulate their target genes in a context-specific manner given the presence of intrinsically disordered regions at their N- and C-termini. After identifying direct PLT targets in public databases, we inferred a gene regulatory network driven by PLTs in the root apical meristem in six angiosperm species. Our results suggest that the direct PLT targets regulate ribosome and ribonucleoprotein biogenesis as well as RNA processing, among other basic cellular processes. The central relevance of these processes may account for the high conservation and stability of PLT-driven gene regulatory networks across angiosperms.
Prophage induction contributes to alterations in the gut phageome during intestinal inflammation
Authors: Sinha Anshul , Qian Amy , Boutin Tommy , Maurice Corinne F.
Published: December 2024

Bacteriophages (phages) are abundant members of the gut microbiota and regulators of bacterial communities. During homeostasis, gut phage communities are longitudinally stable and lysogenic replication is dominant. In chronic gut inflammatory disorders, such as inflammatory bowel diseases (IBDs), there are alterations in phage diversity, which may result from changes in phage replication cycle dynamics. Here, we used a combination ofin vitro, simplified community, and whole-community bioinformatics approaches to investigate whether prophage induction contributes to these alterations. We identified several compounds associated with gut inflammation that induced prophages in commensal gut bacterial isolates. Analysing data from two mouse models of colitis, we observed that shifts in the composition of temperate phages occur over the course of inflammation, supporting a switch from lysogenic to lytic replication. Collectively, our observations support the idea that prophage induction contributes to alterations in the phageome associated with inflammation.
The SWIB domain-containing DNA topoisomerase I ofChlamydia trachomatismediates DNA relaxation
Authors: Shen Li , Diggs Caitlynn , Ferdous Shomita , Santos Amanda , Wolf Neol , Terrebonne Andrew , Carvajal Luis Lorenzo , Zhong Guangming , Ouellette Scot P. , Tse-Dinh Yuk-Ching
Published: December 2024

The obligate intracellular bacterial pathogen,Chlamydia trachomatis(Ct), has a distinct DNA topoisomerase I (TopA) with a C-terminal domain (CTD) homologous to eukaryotic SWIB domains. Despite the lack of sequence similarity at the CTDs betweenC. trachomatisTopA (CtTopA) andEscherichia coliTopA (EcTopA), full-length CtTopA removed negative DNA supercoilsin vitroand complemented the growth defect of anE. coli topAmutant. We demonstrated that CtTopA is less processive in DNA relaxation than EcTopA in dose-response and time course studies. An antibody generated against the SWIB domain of CtTopA specifically recognized CtTopA but not EcTopA orMycobacterium tuberculosisTopA (MtTopA), consistent with the sequence differences in their CTDs. The endogenous CtTopA protein is expressed at a relatively high level during the middle and late developmental stages ofC. trachomatis. Conditional knockdown oftopAexpression using CRISPRi inC. trachomatisresulted in not only a developmental defect but also in the downregulation of genes linked to nucleotide acquisition from the host cells. Because SWIB-containing proteins are not found in prokaryotes beyondChlamydiaspp., these results imply a significant function for the SWIB-containing CtTopA in facilitating the energy metabolism ofC. trachomatisfor its unique intracellular growth.

Importance

C. trachomatis(Ct) is a medically important bacterial pathogen that is responsible for the most prevalent sexually transmitted bacterial infection. Bioinformatics, genetics, and biochemical analyses have established that the presence of a SWIB domain in CtTopA, a DNA topoisomerase I, is relevant to chlamydial physiology. Further defining the mechanisms of the C-terminal SWIB domain on the catalytic function of CtTopA in an intracellular pathogen is warranted for a more complete understanding of the interactions betweenC. trachomatisand its host cells.
Production of the cobalamin lower ligand, 5,6-dimethylbenzimidazole, by a diatom under cobalamin-deplete conditions
Authors: Gleason Anna K. , Bannon Catherine C. , Bertrand Erin M.
Published: December 2024

Cobalamin, or vitamin B12, is a micronutrient required by half of all surveyed phytoplankton but produced only by select bacteria and archaea. Cobalamin influences community composition and primary productivity in various regions of the ocean and has been shown to be a critical currency in microbial interactions. Many prokaryotes and some phytoplankton can salvage and remodel cobalamin-related compounds, e.g. cobinamides and/or pseudocobalamin, to generate cobalamin using the lower ligand 5,6-dimethylbenzimidazole (DMB). The sources of DMB remain poorly characterized but are currently attributed to prokaryotes alone. Here, we grew axenic cultures of a recently isolatedThalassiosiraceaediatom over a range of cobalamin concentrations (0, 0.75, 10, 100 pM). Then, using mass spectrometry, we quantified cobalamin and DMB in both particulate (cellular) and dissolved (media) phases. We found that this diatom is a facultative cobalamin consumer: it takes up cobalamin when available but can survive in its absence. Strikingly, under low cobalamin availability, we demonstrate that the diatom produces DMB. This highlights eukaryotic production as a source of the molecule and suggests that cobalamin remodeling by phytoplankton may be less dependent on prokaryotes than previously imagined. We detected DMB in the media during stationary phase, highlighting eukaryotic production of the molecule as a public good. We provide evidence that DMB is produced by this diatom as a mechanism to cope with low cobalamin availability, suggesting that even amongst organisms that don’t absolutely require it, cobalamin use has important consequences for fitness.

Importance Section

Cobalamin (vitamin B12) is a scarce micronutrient in the ocean that impacts the composition and activity of marine microbial communities. Microbes employ a range of strategies to cope with low cobalamin availability, including remodeling degraded cobalamin compounds into cobalamin if DMB, a critical component of cobalamin, is available. Here we show that a recently isolatedThalassiosiraceaediatom doesn’t need cobalamin to survive, but will take it up and use it when available. Additionally, the diatom produces DMB under low cobalamin conditions. DMB production was previously thought to be restricted to bacteria and archaea, so these results suggest cobalamin remodeling by phytoplankton is not as dependent on interactions with prokaryotes as previously imagined. This work also demonstrates that even organisms that don’t absolutely require cobalamin for survival have adopted metabolic strategies to cope with its absence, emphasizing the importance of this vitamin for phytoplankton metabolism.
Dynamic interplay between RNAN6-methyladenosine modification and porcine reproductive and respiratory syndrome virus infection
Authors: Wang Zi-Han , Li Jing , Ma Sai-Ya , Liu Meng-Xuan , Zhan Yu-Fei , Jin Feng , Liu Bing-Xin , Wang Wenjing , He Mei , Yang Yu-Chuan , Tang Yandong , Wang Peng , Zhang Wuchao , Tong Jie
Published: December 2024

N6-methyladenosine (m6A) has attracted significant attention for its role in various biological processes, including RNA stability, translation, and the immune response. Understanding the role of m6A in viral infections is crucial to deep the complex interaction between virus and host cells. Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a significant pathogen affecting swine health worldwide. Here, we firstly identified the m6A peaks in the PRRSV genome by m6A RNA immunoprecipitation sequencing (m6A-seq). Seven m6A-enriched regions within the PRRSV genome were detected, with one located in the N protein-coding region and the others distributed across nonstructural protein-coding regions. Notably, the Nsp2-coding region contained the highest m6A peak, spanning approximately 178 nucleotides. Functional analyses demonstrated a positive correlation between m6A modification levels and PRRSV replication in porcine alveolar macrophages (PAMs), as modulating the expression of m6A methyltransferases and demethylases significantly influenced viral replication. Moreover, treatment with the universal methylation inhibitor 3-deazaadenosine (3-DAA) effectively suppressed PRRSV replication, suggesting its potential as a novel anti-PRRSV therapeutic. To further elucidate the role of m6A in PRRSV infection, we analyzed the m6A landscape in PAMs infected with pandemic and highly pathogenic PRRSV strains. Among the 4,677 transcripts exhibiting altered m6A modification levels, the MAPK14 gene as well as other genes in p38/MAPK signaling pathway potentially emerged as the preliminary targets of m6A-mediated epigenetic regulation during PRRSV infection. These findings provide new insights into the epigenetic mechanisms underlying PRRSV infection and may facilitate the development of targeted anti-PRRSV strategies and therapeutics.

IMPORTANCE

The involvement of m6A in viral genome has broader implications for our understanding of virus evolution and pathogenicity. The ability of viruses to adapt to their hosts and exploit host cellular mechanisms is a critical factor in their success as pathogens. As m6A is a modification that can be manipulated by both host and virus, studying its role in viral infections may reveal new insights into viral evolution. Understanding how different viruses utilize m6A could inform strategies for developing antiviral therapies that target these interactions. Such therapies could disrupt the ability of viruses to exploit m6A modifications, potentially reducing their virulence and enhancing host defenses.
TurboID-based proximity labeling discovers ABCF2 as an adhesion receptor for the zoonotic pathogenPasteurella multocida
Authors: Wang Fei , Shang Yuyao , Chen Menghan , Wang Zhihao , Liu Hanyuan , Hua Lin , Li Wentao , Chen Huanchun , He Qigai , Wu Bin , Peng Zhong
Published: December 2024

Pasteurella multocidais a zoonotic pathogen that can cause fatal infections in both animals and humans. A significant number of putative adhesive factors have been predicted to contribute to the pathogenesis ofP. multocida, but their interactive proteins on host cells remain unclear. In this study, we experimentally verified the roles of three previously proposed proteins (PlpE, PtfA, Hsf-2) in the adherence ofP. multocida. Through turboID-based proximity labeling screening, we identified ATP-binding cassette sub-family F member 2 (ABCF2) as a host interactive protein for PlpE/PtfA/Hsf-2. Crucial amino acid residues in PlpE, PtfA, and/or Hsf-2 that are essential for interacting with ABCF2 included Asp-123 (PlpE), Lys-88 (PtfA), Asp-136 (PtfA), Ala-464 (Hsf-2), Glu-473 (Hsf-2), and Arg-489 (Hsf-2). Knocking down or knocking out ABCF2 significantly reduced the adherence and invasion ofP.multocidato host cells, while overexpression of ABCF2 markedly increased these effects. However, ABCF2 did not contribute to the adherence of other bacterial species such asKlebsiella pneumoniaeandBordetella bronchiseptica. Additionally, we demonstrated thatP. multocidainfection upregulated the expression of host ABCF2 by activating the p38 MAPK and NF-κB signaling pathways. Furthermore, we showed that ABCF2 was involved in theP. multocida-induced p53-dependent apoptotic signaling pathway. To the best of our knowledge, this is the first identification of ABCF2 as a host factor contributing to the adherence ofP. multocidaand only the second report of ABCF2’s involvement in bacterial pathogenesis.

Importance

P. multocidacan cause fatal infections in both animals and humans, yet the mechanisms related to its pathogenesis remain to be fully explored. In this study, we identified ABCF2 as a crucial host interactive protein for three adhesive proteins encoded byP. multocidaand experimentally verified its role in the adherence and invasion ofP. multocida. Furthermore, we elucidated howP. multocidamodulates ABCF2 during its infection and revealed p53-dependent apoptosis as a downstream effect of ABCF2 duringP. multocidainfection. Given the absence of reports on ABCF2 contributing to the pathogenesis ofP. multocidaand only one previous report on the involvement of ABCF2 in bacterial pathogenesis prior to this study, this research could be valuable for comprehending the interactions between bacteria and hosts during bacterial infections.
PqsE acts as an adaptor protein for the quorum-sensing transcription factor RhlR inPseudomonas aeruginosa
Authors: Tchadi Bilalay V. , Derringer Jesse J. , Detweiler Anna K. , Taylor Isabelle R.
Published: December 2024

Pseudomonas aeruginosais a human pathogen that poses a significant health threat. Pathogenic behaviors ofP. aeruginosaare under control of the bacterial cell-cell communication system known as quorum sensing (QS). One of the QS master regulators, RhlR, is a receptor/transcription factor that not only relies on binding of its canonical ligand, C4-homoserine lactone (HSL), but additionally requires a protein-protein interaction with the enzyme, PqsE. We constructed heterologous reporter strains inEscherichia colithat allow measurements of the reliance of RhlR on C4-HSL and/or PqsE-binding for the ability to activate transcription of three RhlR-regulated genes:rhlA(PqsE-independent),phzM(PqsE-dependent), andazeB(PqsE-suppressed). Analogous assays measuring activation of the three genes inP. aeruginosawere performed and the patterns observed correlated tightly with the heterologous reporter assays. These results indicate that binding of PqsE to RhlR is able to fine-tune RhlR transcription factor activity in a promoter-specific manner.

Importance

Pseudomonas aeruginosais an opportunistic human pathogen that can cause fatal infections. There exists an urgent need for new, effective antimicrobial agents to combatP. aeruginosa. The PqsE-RhlR protein-protein interaction is essential forP. aeruginosato be able to make toxins, form biofilms, and infect host organisms. In this study, we use both non-native models inE. coliand measurements of gene expression/toxin production inP. aeruginosato show that the PqsE-RhlR interaction enables fine-tuned gene expression and a heightened ability ofP. aeruginosato adapt to external conditions. These findings will be highly valuable as continued efforts are made to design inhibitors of the PqsE-RhlR interaction and test them as potential antimicrobial agents againstP. aeruginosainfections.
mRNArchitect: optimized design of mRNA sequences
Authors: Budzinska Magdalena A. , Leonard Theodore E. , Chang Rachel Y. , Chaudhary Natasha , Cheetham Seth W. , Mercer Timothy R. , Gunter Helen M.
Published: December 2024

mRNA design is the critical first step in the development of a new vaccine or therapy. The mRNA primary sequence is assembled from multiple elements, including the coding sequence of the target protein or gene, flanking untranslated regions that enhance translation, and the poly(A) tail, which improves mRNA stability. The coding sequence can also be optimized to improve translation and stability, and the depletion of uridines and double-stranded RNA secondary structures can reduce reactogenicity. Here, we introducemRNArchitect, a software toolkit to assist in the design of mRNA sequences according to user requirements.mRNArchitectcan rapidly assemble and optimize mRNA sequences based on criteria including GC content, secondary structure, codon optimization, and uridine depletion. The sequences generated bymRNArchitectcan also be readily synthesized into DNA templates, and have been validated across a variety of applications. We offermRNArchitectas an open-source software toolkit to help scientists design new mRNA medicines.

Availability and implementation

mRNArchitectis available via a web portal atwww.basefacility.org.au/software/and Github athttps://github.com/BaseUQ/mRNArchitect.mRNArchitectis open-source and freely available under MIT License.
The MpANT-auxin loop modulatesMarchantia polymorphadevelopment
Authors: Dipp-Alvarez Melissa , Lorenzo-Manzanarez J. Luis , Flores-Sandoval Eduardo , Méndez-Álvarez Domingo , Espinal-Centeno Annie , León-Ruiz Jesús , Olvera-Martínez Fernando , Bowman John L. , Arteaga-Vázquez Mario A. , Cruz-Ramírez Alfredo
Published: December 2024

AINTEGUMENTA-LIKE/PLETHORA(APB)genes are considered part of the ancestral developmental toolkit in land plants. InArabidopsis thaliana, these transcription factors are induced by auxin and are primarily expressed in tissues with actively dividing cells, where they play essential roles in organ development.Marchantia polymorpha, a liverwort that diverged fromA. thalianaearly in embryophyte evolution, possesses a singleAPBortholog, MpAINTEGUMENTA(MpANT), encoded in its genome. In this study, we aimed to characterize the function of MpANT. Analysis of a transcriptional fusion line indicates that MpANTis predominantly expressed in the meristematic region. We report that the MpANTpromoter region contains severalcis-acting Auxin Responsive Elements (AREs) and demonstrate that its expression, which occurs predominantly in meristematic regions, is significantly altered by addition of exogenous auxin and inhibition of auxin transport. These findings indicate that MpANTacts downstream of Auxin Response Factors (ARFs) and auxin signaling. Analyses of loss- and gain-of-function MpANTalleles highlight the importance of this transcription factor in meristem maintenance and cell proliferation. Additionally, we found that MpANTacts upstream of the auxin transporter MpPIN1by influencing auxin distribution. Taken together, our findings reveal a feedforward regulatory loop involving auxin, MpANT, and MpPIN1that is important for Marchantia development.
Linguistic networks uncover grammatical constraints of protein sentences comprised of domain-based words
Authors: Shimpi Adrian A. , Naegle Kristen M.
Published: December 2024

Evolution has developed a set of principles that determine feasible domain combinations analogous to grammar within natural languages. Treating domains as words and proteins as sentences, made up of words, we apply a linguistic approach to represent the human proteome as an n-gram network. Combining this with network theory and application, we explore the functional language and rules of the human proteome. Additionally, we explored subnetwork languages by focusing on reversible post-translational modifications (PTMs) systems that follow a reader-writer-eraser paradigm. We find that PTM systems appear to sample grammar rules near the onset of the system expansion, but then convergently evolve towards similar grammar rules, which stabilize during the post-metazoan switch. For example, reader and writer domains are typically tightly connected through shared n-grams, but eraser domains are almost always loosely or completely disconnected from readers and writers. Additionally, after grammar fixation, domains with verb-like properties, such as writers and erasers, never appear – consistent with the idea of natural grammar that leads to clarity and limits futile enzymatic cycles. Then, given how some cancer fusion genes represent the possibility for the emergence of novel language, we investigate how cancer fusion genes alter the human proteome n-gram network. We find most cancer fusion genes follow existing grammar rules. Collectively, these results suggest that n-gram based analysis of proteomes is a complement to the more direct protein-protein interaction networks. N-grams can capture abstract functional connections in a more fully described manner, limited only by the definition of domains within the proteome and not by the combinatorial challenge of capturing all protein interaction connections.
Newtonian restricted three-body gravitational problem with positive and negative point masses
Authors: Thong Kok Hong , Melatos Andrew
Published: December 2024

The Newtonian restricted three-body problem involving a positive primary point mass, m+, and a negative secondary point mass, m−, in a circular orbit, and a positive or negative tertiary point mass, m3, with m+>|m−|≫|m3|, is solved. Five Lagrange points are found for m3, three of which are coplanar with m+ and m−, and two of which are not, a subtle consequence of the gravitational repulsion from m−. All Lagrange points are linearly unstable, except for one point in the regime m+≳8.4|m−|, which is linearly stable and collinear with m+ and m−.

Published by the American Physical Society
2024
Algebraic structures in closed superstring field theory, homotopy transfer, and effective actions
Authors: Singh Ranveer Kumar
Published: December 2024

A consistent action for heterotic and type II superstring field theory was recently proposed by Sen. We give an algebraic formulation of this action in terms of certain twisted L∞ algebra. We further show that Sen’s Wilsonian effective superstring field action can be obtained using homotopy transfer and the effective theory also possesses the algebraic structure of a twisted L∞ algebra.

Published by the American Physical Society
2024
Robust double Bragg diffraction via detuning control
Authors: Li Rui , Martínez-Lahuerta V. J. , Seckmeyer S. , Hammerer Klemens , Gaaloul Naceur
Published: December 2024

We present a theoretical model and numerical optimization of double Bragg diffraction, a widely used technique in atom interferometry. We derive an effective two-level-system Hamiltonian based on the Magnus expansion in the so-called quasi-Bragg regime, where most Bragg-pulse atom interferometers operate. Furthermore, we extend the theory to a five-level description to account for Doppler detuning. Using these derived effective Hamiltonians, we investigate the impacts of AC-Stark shift and polarization errors on the double Bragg beam splitter, along with their mitigations through detuning control. Notably, we design a linear detuning sweep that demonstrates robust efficiency exceeding 99.5% against polarization errors up to 8.5%. Moreover, we develop an artificial-intelligence-aided optimal detuning control protocol, showcasing enhanced robustness against both polarization errors and Doppler effects. This protocol achieves an average efficiency of 99.92% for samples with a finite momentum width of 0.05ℏkL within an extended polarization error range of up to 10%.

Published by the American Physical Society
2024
Physical consequences of Lindbladian invariance transformations
Authors: de Almeida Yohan Vianna , Nicacio Fernando , Santos Marcelo F.
Published: December 2024

On its own, the invariance properties of Markovian master equations have mostly played a mathematical or computational role in the evaluation of quantum open system dynamics. Because all forms of the equation lead to the same time evolution for the state of the system, the fixation of a particular form has only gained physical meaning when correlated with additional information such as in the evolution of quantum trajectories or the study of decoherence-free subspaces. Here, we show that these symmetry transformations can be exploited, on their own, to optimize practical physical tasks. In particular, we present a general formulation showing how they can be used to change the measurable values of physical quantities regarding the exchange of energy and/or information with the environment. We also analyze examples of optimization in quantum thermodynamics and, finally, discuss practical implementations in terms of quantum trajectories.

Published by the American Physical Society
2024
Symmetry-Enforced Entanglement in Maximally Mixed States
Authors: Moharramipour Amin , Lessa Leonardo A. , Wang Chong , Hsieh Timothy H. , Sahu Subhayan
Published: December 2024

Entanglement in quantum many-body systems is typically fragile to interactions with the environment. Generic unital quantum channels, for example, have the maximally mixed state with no entanglement as their unique steady state. However, we find that for a unital quantum channel that is “strongly symmetric,” i.e., it preserves a global on-site symmetry, the maximally mixed steady state in certain symmetry sectors can be highly entangled. For a given symmetry, we analyze the entanglement and correlations of the maximally mixed state in the invariant sector (MMIS) and show that the entanglement of formation and distillation are exactly computable and equal for any bipartition. For all Abelian symmetries, the MMIS is separable and for all non-Abelian symmetries, the MMIS is entangled. Remarkably, for non-Abelian continuous symmetries described by compact semisimple Lie groups (e.g., SU(2)), the bipartite entanglement of formation for the MMIS scales logarithmically with the number of qudits N.

Published by the American Physical Society
2024
Psychological capital and the entrepreneurial performance of migrant workers: intermediary role of entrepreneurial opportunity identification
Authors: Ma Hongyu , Zhang Yongmei Carol , Topolansky Barbe Federico Guillermo , Stuart Mark
Published: December 2024

Purpose

There is a pressing need for research on the difference in entrepreneurial performance influenced by the integration of migrant workers’ psychological capital and entrepreneurial opportunity identification. In addition, there is limited research on the association of entrepreneurial performance with different dimensions of psychological capital and how these dimensions affect the entrepreneurial performance of migrant workers. This research will partially address this gap in knowledge by assessing the influence of psychological capital and entrepreneurial opportunity identification on the entrepreneurial performance of migrant workers in China.

Design/methodology/approach

This paper conducts a theoretical analysis of psychological capital, entrepreneurial opportunity identification and entrepreneurial performance and proposes a theoretical model of entrepreneurial opportunity identification acting as the intermediary role between psychological capital and the entrepreneurial performance of migrant workers. Based on the data collected from 899 rural households in Shaanxi Province, a structural equation model and a bootstrap method are used to verify the association between psychological capital, entrepreneurial opportunity identification and entrepreneurial performance.

Findings

Both entrepreneurial opportunity identification and psychological capital are conducive to the improvement of entrepreneurial performance. However, the entrepreneurial opportunity identification is found to exert a more significant impact on the entrepreneurial performance of migrant workers than psychological capital does. Findings have also revealed that the intermediary role of entrepreneurial opportunity identification is more prominent in the relationship between adventure and innovation and the entrepreneurial performance of migrant workers than that of self-confidence and optimism and entrepreneurial performance of migrant workers.

Originality/value

Based on the results of empirical analysis, the paper proposes corresponding policy recommendations for guiding migrant workers to capitalize on their psychological capital, identify entrepreneurial opportunities, weigh up entrepreneurial risks and ultimately improve their entrepreneurial performance.
Full-cycle grids numerical simulation of the performance for newly developed micro turbine engine
Authors: Zhang Tianhe , Wu Lihong , Li Zheng , Liu Shewen
Published: December 2024

Purpose

The purpose of this research is to investigate the feasibility of using the components series connection (CSC) method to predict the performance of a newly developed micro turbine engine (MTE) under rated operating condition.

Design/methodology/approach

The main research object is the MTE with known factory performance parameters, and the finite element method is used to discretize its main components into a full-cycle grid and then simulate it in the computational fluid dynamics method under rated operating condition using the CSC method. Finally, compare the results obtained by numerical simulations with the factory design parameters of the MTE.

Findings

The performance and flow field of MTE and each component were simulated and obtained. Compared with the factory design parameters, the errors are acceptable, with the outlet average total temperature and thrust exhibiting errors of 1.4% and 7.6%, respectively.

Practical implications

This paper introduces a faster and more convenient method for simulating the performance of MTE components and the entire engine while also making the simulations more realistic. The method was used to analyze the performance of the components and the whole engine of a newly developed MTE.

Originality/value

This research validates the feasibility of evaluating the overall performance of the MTE using the CSC method and provides a new method to solve performance calculations for MTE under any known working conditions.
Efficacy of growth-led unemployment reduction hypothesis in India using Okun’s law
Authors: Sharma Akhilesh Kumar , Rai Sushil Kumar
Published: December 2024

Purpose

The purpose of this paper is to examine whether increased labour productivity could reduce the impact of output growth on the unemployment rate in India over the period 1991–2019 through Okun’s law and its expanded form.

Design/methodology/approach

The study uses Okun’s law and its expanded form, with the inclusion of labour productivity in the actual model. Further, the relationship between output growth, unemployment rate, and labour productivity is analysed by using the gap model, the difference model, the dynamic model, the error correction model (ECM), and the vector autoregressive (VAR) approach.

Findings

The empirical results from the applied models do not confirm an inverse relationship between output growth and the unemployment rate with an unexpected positive sign of Okun’s coefficient. The evidence of preference for more capital-intensive techniques in the Indian economy is also strongly supported by the results of the expanded form of Okun’s law with a statistically significant positive coefficient of GDP and labour productivity.

Originality/value

The study examined the proposed relationship using Okun’s law and its expanded form, which had not been employed in earlier studies in the context of India. The authors also show that a high economic growth rate is a necessary but not sufficient condition to solve the chronic and structural unemployment problem in India.
Evaluation of the impact of oleic acid-capped Al2O3 nanoparticles on the tribological performance of conventional lube oil
Authors: Singh Anoop Pratap , Dwivedi Ravi Kumar , Suhane Amit , Madhuri K. Sudha , Shende Vikas
Published: December 2024

Purpose

This study aims to evaluate the influence of oleic acid (OA)-capped Al2O3 nanoparticles on the tribological performance of conventional lube oil. The goal is to determine the optimal nanoparticle concentration that enhances lubricant efficiency by reducing friction and wear.

Design/methodology/approach

The research involved preparing nanolubricants with four different concentrations of Al2O3 nanoparticles: 0.05, 0.1, 0.25 and 0.5 wt.%. Tribological performance was assessed using a four-ball tribotester, which measured the coefficient of friction (COF) and wear scar diameter (WSD) under standardized testing conditions.

Findings

The experimental results revealed that the nanolubricant containing 0.1 wt.% OA-Al2O3 nanoparticles exhibited the most significant improvement in tribological performance. This formulation achieved a 38.84% reduction in COF and a 23.87% reduction in WSD compared to the base lubricant. These findings demonstrate the effectiveness of incorporating OA-capped Al2O3 nanoparticles in reducing friction and wear, thereby enhancing the overall performance of conventional lubricants.

Originality/value

This study demonstrates the benefits of OA-capped Al2O3 nanoparticles in lubricants, including a 38.84% reduction in COF and a 23.87% reduction in WSD. By systematically analyzing different nanoparticle concentrations, it identified that 0.1% by weight of nanoparticles is the most effective formulation for reducing friction and wear.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0236/
Examining the use of multiple cognitive load measures in evaluating online shopping convenience: an EEG study
Authors: Mirhoseini Mahdi , Léger Pierre-Majorique , Sénécal Sylvain
Published: December 2024

Purpose

In the past decade, the use of neurophysiological measures as a complementary source of information has contributed to our understanding of human–computer interaction. However, less attention has been given to their capability in providing measures with high temporal resolution. Two studies are designed to address the challenge of measuring users’ cognitive load in an online shopping environment and investigate how it is related to task difficulty, task uncertainty and shopping convenience.

Design/methodology/approach

Two experiments using behavioral and neurophysiological measures are conducted to investigate how various types of the cognitive load construct can be measured and used in an online shopping context.

Findings

Results of the first study suggest that although all cognitive load measures are influenced by task difficulty, only accumulated load (i.e. total cognitive load experienced during a task) is sensitive to task uncertainty. Results of the second study show that convenience negatively influences accumulated load, and the latter negatively influences user satisfaction.

Practical implications

Our research offers practical value by providing designers with a validated method to measure users’ cognitive load, enabling the identification of usability issues and design improvement.

Originality/value

This study contributes to the literature by developing a rich and temporally high-resolution measurement of the cognitive load construct and examining how it can inform us about users’ cognitive state in an online shopping environment.
Towards a better understanding of customer satisfaction with shopping mall food courts
Authors: Dabral Paritosh , Chelamallu Karunya , Sthapit Erose , Björk Peter , Piramanayagam Senthilkumaran
Published: December 2024

Purpose

In this study, we examined the attributes that determine shoppers’ satisfaction with food courts in shopping malls and the effects of this satisfaction on behavioural intentions towards shopping malls.

Design/methodology/approach

The data for this study were collected from 380 shoppers who visited food courts in shopping malls located in Hyderabad, India. The data were analysed using structural equation modelling.

Findings

The results indicate that fair prices, authenticity and the quality of the food, service and environment predict shoppers’ dining satisfaction and behavioural intentions. The findings also indicate that satisfaction with food court experiences has a strong positive influence on shoppers’ intention to revisit shopping malls.

Practical implications

Food service providers in Indian shopping malls should recognise that offering suitably priced and high-quality experiences is vital for sustaining their businesses in the long term as well as offer prompt service and warm hospitality to visitors to enhance customer satisfaction.

Originality/value

This study has implications for mall operators and food court managers seeking to enhance customer satisfaction with food courts and sustain the success of shopping malls. To the best of our knowledge, this is the first study to examine the factors that influence shoppers’ dining satisfaction and behavioural intentions in this context.
Preferences and attitudes on acetate‐ versus lactate‐buffered crystalloid solutions for intravenous fluid therapy—An international survey
Authors: Ellekjaer Karen Louise , Sivapalan Praleene , Myatra Sheila N. , Grønningsæter Lasse , Hästbacka Johanna , Young Paul J. , Boyle Andrew J. , Ostermann Marlies , Pfortmueller Carmen A. , Jovaišienė Ieva , De Waele Jan , Reintam Blaser Annika , Al‐Fares Abdulrahman , Khanna Ashish K. , Arabi Yaseen M. , Fujii Tomoko , Keus Eric , Mer Mervyn , Alshamsi Fayez , Cronhjort Maria , Perner Anders , Møller Morten H. ,   National and site investigators
Published: December 2024

Background

Clinical practice guidelines recommend use of buffered crystalloid solutions in critically ill patients but do not distinguish between solutions based on different buffering anions, that is, acetate‐ versus lactate‐buffered solutions. We therefore surveyed relevant physicians about their preferences and attitudes toward each solution.

Methods

We conducted an international online survey of anesthesiologists (within perioperative care) and intensive care unit (ICU) physicians. The survey comprised 13 questions on respondents' attitudes and preferences regarding the use of acetate‐ and/or lactate‐buffered crystalloid solutions, including their opinions on a potential clinical trial comparing these solutions and the clinical importance of such a trial.

Results

A total of 1321 respondents participated, with a response rate of 34%, ranging from 14% to 96% across 18 countries. Most surveyed physicians reported using buffered crystalloid solutions “very often” (76%) or “often” (16%). Availability of acetate‐ and lactate‐buffered solutions varied, as 35% of respondents reported having both types available, 35% reported having only acetate‐, and 24% reported having only lactate‐buffered solutions available.

Most respondents (87%) would support a randomized trial in adult emergency surgical patients and ICU patients comparing an acetate‐ versus lactate‐buffered crystalloid solution. The median rating of the clinical importance of this question was 5 (interquartile range 4–6) on a scale from 1 to 9.

Conclusions

In this international survey, the reported use of buffered crystalloid solutions was high. Availability of the different solutions varied widely. The support for a potential randomized trial was high, with the clinical importance rated important but not critical by most respondents.
Gut microbiota metabolism of branched‐chain amino acids and their metabolites can improve the physiological function of aging mice
Authors: Wang Hongchao , Feng Ling , Pei Zhangming , Zhao Jianxin , Lu Shourong , Lu Wenwei
Published: December 2024

The metabolism of branched‐chain amino acids by gut microbiota can improve overall health and may reverse aging. In this study, we investigated Parabacteroides merdae, a gut microbe that is known to catabolise branched‐chain amino acids (BCAAs). Three metabolites of BCAAs isovalerate, 2‐methylbutyrate, and isobutyrate were used to treat D‐gal induced aging mice. The results showed that these treatments could delay aging in mice by providing health benefits in reducing oxidative stress and inflammation, improving muscle capacity, reversing brain acetylcholine levels, and regulating blood glucose. The mechanism was preliminarily explored by combining the gut microbiota metagenome and faecal serum metabolome. Parabacteroides merdae altered the species composition and structure of the gut microbiota in mice. Increasing the abundance of beneficial bacteria, such as Bifidobacterium pseudolongum. Three metabolites affects the gut microbiota and the body's pathways of protein and improves the overall health through a variety of signaling pathways. Overall, regulating the gut microbiota involved in branched‐chain amino acid metabolism to bring health benefits may be a new way of reversing aging.
Randomized Controlled Trials of Psilocybin‐Assisted Therapy in the Treatment of Major Depressive Disorder: Systematic Review and Meta‐Analysis
Authors: Menon Vikas , Ramamurthy Parthasarathy , Venu Sandesh , Andrade Chittaranjan
Published: December 2024

Introduction

There is growing interest in the use of psychedelic‐assisted therapy (PAT) for major depressive disorder (MDD), including treatment‐resistant depression. We used randomized controlled trial (RCT) data to compare summary estimates of change in depression ratings with PAT versus comparator treatments in MDD. We also compared response and remission rates, and adverse effects.

Methods

We searched MEDLINE, EMBASE, Cochrane Central Register for Controlled Trials (CENTRAL), and SCOPUS from inception till April 2024. Our primary efficacy outcome was 1‐week (or nearest) between‐group change in depression ratings. Secondary efficacy outcomes were changes in depression ratings at days 2, 14, and 42 (or nearest) and study‐defined response and remission rates at week 1 (or nearest). Safety outcomes were reported adverse effects. We pooled outcomes in random‐effects meta‐analyses using standardized mean difference (SMD; Hedges g) for continuous outcomes and risk ratio (RR) for categorical outcomes.

Results

We found 6 eligible RCTs (pooled N = 427), all on psilocybin. The pooled SMD for 1‐week between‐group change in depression ratings was −0.72 [95% CI, −0.95 to −0.49; I2 = 17%; 5 RCTs; n = 403], favouring PAT; results were similar at days 2, 14, and 42. The response [RR = 3.42; 95% CI, 2.35–4.97; I2 = 0%; 4 RCTs; n = 373] and remission [RR = 3.66; 95% CI, 2.26–5.92; I2 = 0%; 4 RCTs; n = 373] rates also favored PAT. The PAT group had a small but significantly increased risk of developing any adverse event [RR = 1.20; 95% CI, 1.01–1.42; I2 = 43%; 4 RCTs; n = 373] and a significantly higher risk of experiencing headache [RR = 1.78; 95% CI, 1.10–2.86; I2 = 52%; 4 RCTs; n = 373] and dizziness [RR = 6.52; 95% CI, 1.19–35.87; I2 = 0%; 3 RCTs; n = 269]. Low heterogeneity characterized most analyses and findings were similar in sensitivity analyses.

Conclusion

Antidepressant effects of psilocybin‐assisted therapy are superior (with at least medium effect sizes) to comparator interventions for at least up to 6 weeks postintervention.
A literature review of model fit and model comparisons with confirmatory factor analysis: Formalizing the informal in organizational science
Authors: Howard Matt C. , Boudreaux Melanie , Cogswell Joshua , Manix Kelly G. , Oglesby Matthew T.
Published: December 2024

Researchers often stray from recommendations provided by simulation studies when conducting confirmatory factor analysis (CFA), causing unwieldy applications of the analysis and diminished confidence in published results. We introduce three particularly important informal practices associated with (1) alternative interpretations of model fit, (2) the use of inadvisable combinations of fit indices, and (3) the failure to conduct effective model comparisons. We then review over 2000 CFAs in premier organizational science journals. Our results support that researchers widely engage in all three informal practices. To address this tension, we (1) formalize modern interpretations of model fit by providing percentile ranges of indices in published articles, such that researchers can make relative and continuous assessments of model fit. We (2) emphasize the importance of assessing multiple recommended fit indices together to provide complete depictions of model soundness. Lastly, we (3) demonstrate the necessity to perform appropriate model comparisons, including the assessment of more complex models.
A retrospective analysis of clinical features, management and outcomes in dogs and cats with Eastern Brown Snake envenomation (2016–2022)
Authors: Day SK , Nash KJ , Midwinter MJ , Goodwin WA
Published: December 2024

Australian Eastern brown snakes (Pseudonaja textilis) can cause venom‐induced consumptive coagulopathy (VICC) in envenomated dogs and cats due to toxin‐induced consumption of clotting factors. The objective of this study was to describe presenting clinical signs, prevalence of VICC and haemorrhage, VICC resolution timelines and patient outcomes in a population of dogs and cats with Eastern brown snake envenomation (EBSE). Data from dogs and cats presenting with EBSE were retrospectively evaluated. Univariable and multivariable analyses were performed to test predictor variable effects on outcomes. Animals who were euthanased for financial reasons on presentation were excluded from treatment and outcome analysis. Two‐hundred and forty dogs and 98 cats were included. On presentation, 66% (159/240) of dogs had lower motor neuropathy (LMN), 31% (74/240) had preparalytic collapse and 30% (72/240) had signs of haemorrhage. In cats, 94% (92/98) had LMN, and only 5% (5/98) had haemorrhage. Ninety‐two percent of dogs (209/226) and cats (81/88) were diagnosed with VICC on presentation and median time to normalisation of coagulation tests was 24 hours. Median hospitalisation length was 1.5 days for dogs (lower quartile [LQ]–upper quartile [UQ]: 1.0–3.0) and 2 days for cats (LQ – UQ: 1.0–2.5). Dogs presenting with LMN and no history of preparalytic collapse had significantly longer hospitalisation times (median 2.25 vs. 1.0 days, P‐value <0.001; median 2.0 vs. 1.0 days, P‐value <0.001 respectively). Odds of survival was lower in dogs with LMN (odds ratio [OR]: 0.23) and in the pooled multivariable analysis of dogs and cats with haemorrhage (OR: 0.39). The administration of antivenom overall was found to confer a survival advantage; however analysis failed to show increased odds of survival with administration of more than 4000 units. Overall, 89% (187/210) of dogs and 75% (58/77) of cats survived to discharge.