bluuebunny/crossref_metadata_2025 huggingface dataset:
Early life stress-induced miR-708-5p regulates mood disorder-associated behavioural phenotypes in mice and is a potential diagnostic biomarker for bipolar disorder
Authors: Gilardi Carlotta , Martins Helena C. , Bianco Alessandra Lo , Bicker Silvia , Germain Pierre-Luc , Gross Fridolin , Sungur Ayse Özge , Kisko Theresa M. , Stein Frederike , Meinert Susanne , Schwarting Rainer K. W. , Wöhr Markus , Dannlowski Udo , Kircher Tilo , Schratt Gerhard
Published: March 2024

Mood-disorders (MDs) are caused by a complex interplay of genetic and environmental (GxE) risk factors. However, the molecular pathways engaged by GxE risk factors to trigger specific MD-associated endophenotypes are still poorly understood. Here, by using unbiased small RNA sequencing in peripheral blood mononuclear cells (PBMCs), we identified the BD-associated miR-708-5p as one of the most strongly upregulated microRNAs in peripheral blood of both healthy human subjects with a high genetic or environmental (early life stress) predisposition to develop MDs. miR-708 is also upregulated in the hippocampus of rats which underwent juvenile social isolation, a rodent model of early life stress. Furthermore, ectopic overexpression of miR-708-5p in the hippocampus of adult male mice is sufficient to elicit MD-associated behavioural endophenotypes, demonstrating a causal role for elevated miR-708-5p levels in MD development. We further show that miR-708-5p directly targets Neuronatin (Nnat), an endoplasmic reticulum (ER) resident protein involved in calcium homeostasis. Consequently, restoring Nnat expression in the hippocampus of miR-708-5p overexpressing mice rescues miR-708-5p dependent behavioural phenotypes. Finally, miR-708-5p is strongly upregulated in PBMCs derived from patients diagnosed with MD, in particular BD males. Peripheral expression of miR-708-5p, in conjunction with the previously identified miR-499-5p, allows to differentiate male BD patients from patients suffering from major depressive disorder (MDD) and healthy controls. In summary, we describe a functional role for the miR-708-5p/Nnat pathway in MD etiology and identify miR-708-5p as a potential biomarker for the differential diagnosis of MDs.
Slippery sequences stall the 26S proteasome at multiple points along the translocation pathway
Authors: Ragwan Edwin R. , Kisker Faith M. , Morning Amelia R. , Weiser Kaya R. , Lago Athena V. , Kraut Daniel A.
Published: March 2024

In eukaryotes, the ubiquitin-proteasome system is responsible for intracellular protein degradation. Proteins tagged with ubiquitin are recognized by ubiquitin receptors on the 19S regulatory particle (RP) of the 26S proteasome, unfolded, routed through the translocation channel of the RP, and are then degraded in the 20S core particle (CP). Aromatic paddles on the pore-1 loops of the RP’s Rpt subunits grip the substrate and pull folded domains into the channel, thereby unfolding them. The sequence that the aromatic paddles grip while unfolding a substrate is therefore expected to influence the extent of unfolding, and low complexity sequences have been shown to interfere with grip. However, the detailed spatial requirements for grip while unfolding proteins, particularly from the N-terminus, remain unknown. We determined how the location of glycine-rich tracts relative to a folded domain impairs unfolding. We find that, in contrast to a previous report, inserting glycine-rich sequences closer to the folded domain reduced unfolding ability more than positioning them further away. Locations that have the biggest effect on unfolding map onto the regions where the aromatic paddles are predicted to interact with the substrate. Effects on unfolding from locations up to 67 amino acids away from the folded domain suggest that there are additional interactions between the substrate and the proteasome beyond the aromatic paddles that facilitate translocation of the substrate. In sum, this study deepens understanding of the mechanical interactions within the substrate channel by mapping the spacing of interactions between the substrate and the proteasome during unfolding.

Importance

The proteasome processively unfolds and degrades target proteins in eukaryotes. However, some substrates are prematurely released, and the resulting partially degraded proteins can cause problems for cells and can be linked to neurodegenerative diseases. In this paper, we use a series of substrates that can stall the proteasome during degradation to probe the translocation pathway substrates must traverse during unfolding. We find that multiple points along the translocation pathway are impacted by these slippery substrates.
Meiosis-specific functions of kinetochore protein SPC105R required for chromosome segregation inDrosophilaoocytes
Authors: Joshi Jay N. , Changela Neha , Mahal Lia , Defosse Tyler , Jang Janet , Wang Lin-Ing , Das Arunika , Shapiro Joanatta G. , McKim Kim
Published: March 2024

The reductional division of meiosis I requires the separation of chromosome pairs towards opposite poles. We have previously implicated the outer kinetochore protein SPC105R/KNL1 in driving meiosis I chromosome segregation through lateral attachments to microtubules and co-orientation of sister centromeres. To identify the domains of SPC105R that are critical for meiotic chromosome segregation, an RNAi-resistant gene expression system was developed. We found that SPC105R’s C-terminal domain (aa 1284-1960) is necessary and sufficient for recruiting NDC80 to the kinetochore and building the outer kinetochore. Furthermore, the C-terminal domain recruits BUBR1, which in turn recruits the cohesion protection proteins MEI-S332 and PP2A. Of the remaining 1283 amino acids, we found the first 473 are most important for meiosis. The first 123 amino acids of the N-terminal half of SPC105R contain the conserved SLRK and RISF motifs that are targets of PP1 and Aurora B kinase and are most important for regulating the stability of microtubule attachments and maintaining metaphase I arrest. The region between amino acids 124 and 473 are required for two activities that are critical for accurate chromosome segregation in meiosis I, lateral microtubule attachments and bi-orientation of homologs.

Significance Statement

Kinetochore proteins regulate meiosis specific functions. SPC105R is a central regulator of kinetochore function but its role in meiosis is not well understood.

We identified regions of SPC105R that regulate key meiosis I functions, including fusing sister centromeres and the way the kinetochore interacts with the microtubules.

SPC105R is a hub that recruits several proteins to regulate kinetochore activity. Future work will involve identifying the proteins recruited by SPC105R that mediate these functions in meiosis.
Assessing Individual Sensitivity to the Thermal Grill Illusion: A Two-Dimensional Adaptive Psychophysical Approach
Authors: Sardeto Deolindo Camila , Ehmsen Jesper Fischer , Courtin Arthur S. , Mitchell Alexandra G. , Kraenge Camilla E. , Nikolova Niia , Allen Micah G. , Fardo Francesca
Published: March 2024

In the thermal grill illusion (TGI), the spatial alternation of non-noxious warm and cold temperatures elicits burning sensations that resemble the presence of noxious stimuli. Previous research has largely relied on the use of specific temperature values (i.e., 20°C and 40°C) to study this phenomenon in both healthy individuals and patient populations. However, this methodology fails to account for inter-individual differences in thermal sensitivity, limiting the precision with which TGI responses can be evaluated across diverse populations. To address this gap, we created a Two-Dimensional Thermal Grill Calibration (2D-TGC) protocol, enabling an efficient and precise estimation of the combinations of warm and cold temperatures needed to elicit burning sensations tailored to each individual. By applying the 2D-TGC protocol in 43 healthy participants, we demonstrated key findings: (1) The TGI can be thresholded using an adaptive psychophysical method. (2) Multiple combinations of warm and cold temperatures can elicit this phenomenon. (3) The protocol facilitated the identification of temperature combinations that elicit TGI with varying levels of probability, intensity, and perceived quality ranging from freezing cold to burning hot. (4) TGI responsivity can be quantified as a continuous variable, moving beyond the conventional classification of individuals as responders vs. non-responders based on arbitrary temperature values. The 2D-TGC offers a comprehensive approach to investigate the TGI across populations with altered thermal sensitivity, and can be integrated with other methods (e.g., neuroimaging) to elucidate the mechanisms responsible for perceptual illusions in the thermo-nociceptive system.
CAR T cell infiltration and cytotoxic killing within the core of 3D breast cancer spheroids under control of antigen sensing in microwell arrays
Authors: Cho Youngbin , Laird Matthew , Bishop Teddi , Li Ruxuan , Ruffo Elisa , Lohmueller Jason , Zervantonakis Ioannis K.
Published: March 2024

The success of chimeric antigen receptor (CAR) T cells in blood cancers has intensified efforts to develop CAR T therapies for solid cancers. In the solid tumor microenvironment, CAR T cell trafficking and suppression of cytotoxic killing represent limiting factors for therapeutic efficacy. Here, we present a microwell platform to study CAR T cell interactions with 3D tumor spheroids and determine predictors of anti-tumor CAR T cell function. To precisely control antigen sensing by CAR T cells, we utilized a switchable adaptor CAR system, that instead of directly binding to an antigen of interest, covalently attaches to co-administered antibody adaptors that mediate tumor antigen recognition. Following addition of an anti-HER2 adaptor antibody, primary human CAR T cells exhibited higher infiltration and clustering compared to the no adaptor control. By tracking CAR T cell killing at the individual spheroid level, we showed the suppressive effects of spheroid size and identified the initial CAR T cell : spheroid area ratio as a predictor of cytotoxicity. Spatiotemporal analysis revealed lower CAR T cell numbers and cytotoxicity in the spheroid core compared to the periphery. Finally, increasing CAR T cell seeding density, resulted in higher CAR T cell infiltration and cancer cell elimination in the spheroid core. Our findings provide new quantitative insights into CAR T cell-mediated killing of HER2+ breast tumor cells. Given the miniaturized nature and live imaging capabilities, our microfabricated system holds promise for discovering cell-cell interaction mechanisms that orchestrate antitumor CAR T cell functions and screening cellular immunotherapies in 3D tumor models.
Reduced GABA transmission onto ventral tegmental area dopamine neurons underlies vulnerability for hyperactivity in a mouse model of Anorexia Nervosa
Authors: Ducrocq Fabien , Brouwer Eileen , Kooij Karlijn L. , Wolterink-Donselaar Inge G. , Drost Lisa , Hak Jaimie , Veendijk Melissa , Luijendijk Mieneke C. M. , Meye Frank J. , Adan Roger A. H.
Published: March 2024

Anorexia nervosa (AN) has the highest mortality among psychiatric diseases. Hyperactivity is a persistent symptom, which is difficult to control for patients and a major barrier to recovery as it interferes with weight gain. Alteration of mesolimbic dopamine transmission has been hypothesized as a critical factor for the development and maintenance of the disease and for hyperactivity. At what level the changes in dopamine occur in anorexic states and whether local mesolimbic neurocircuit plasticity is causally involved remains unclear. Especially the role of local GABA control over dopamine neurons, a powerful regulator of the dopamine system, in an AN context is unknown. We hypothesize that combining caloric restriction with exercise, such as in the activity-based anorexia (ABA) model, alters dopamine transmission via GABA disinhibition that, in turn, facilitates the expression of maladaptive behaviors such as hyperactivity.

Therefore, we characterized the impact of the ABA model on plasticity of the dopamine reward system. In ex-vivo brain slices of mice exposed to this model, ventral tegmental area dopamine (VTADA) neurons displayed a higher firing frequency compared to control mice supporting that the midbrain dopamine system undergoes plasticity. This coincided with reduced GABAergic transmission on VTADAneurons. This reduction was at least in part attributable to local VTA GABA (VTAGABA) neurons. Indeed, VTAGABAneurons were less excitable, displayed a lower firing frequency and a lower probability of release onto VTADAneurons. Restoring the excitability of VTAGABAneurons via chemogenetic activation rescued mice from starvation, by decreasing running wheel activity.

In summary, we found that the anorexic state leads to dysregulation of VTAGABAtransmission on VTADAneurons that reinforces maladaptive behaviors such as excessive exercise. We uncovered a new mechanism linked to the disturbed dopamine system in ABA-exposed animals, identifying a hitherto unknown role of decreased local GABAergic control over VTA dopamine neuron output.
Pavlovian cue-evoked alcohol seeking is disrupted by ventral pallidal inhibition
Authors: Richard Jocelyn M. , Armstrong Anne , Newell Bailey , Muruganandan Preethi , Janak Patricia H. , Saunders Benjamin T.
Published: March 2024

Cues paired with alcohol can be potent drivers of craving, alcohol-seeking, consumption, and relapse. While the ventral pallidum is implicated in appetitive and consummatory responses across several reward classes and types of behaviors, its role in behavioral responses to Pavlovian alcohol cues has not previously been established. Here, we tested the impact of optogenetic inhibition of ventral pallidum on Pavlovian-conditioned alcohol-seeking in male Long Evans rats. Rats underwent Pavlovian conditioning with an auditory cue predicting alcohol delivery to a reward port and a control cue predicting no alcohol delivery, until they consistently entered the reward port more during the alcohol cue than the control cue. We then tested the within-session effects of optogenetic inhibition during 50% of cue presentations. We found that optogenetic inhibition of ventral pallidum during the alcohol cue reduced port entry likelihood and time spent in the port, and increased port entry latency. Overall, these results suggest that normal ventral pallidum activity is necessary for Pavlovian alcohol-seeking.
A small molecule inhibitor Mirin prevents TOP3A-dependent mtDNA breakage and segregation
Authors: Aasumets Koit , Hangas Anu , Bader Cyrielle P. J. , Erdinc Direnis , Wanrooij Sjoerd , Wanrooij Paulina H. , Goffart Steffi , Pohjoismäki Jaakko L.O.
Published: March 2024

Mirin, the chemical inhibitor of MRE11, has been recently reported to prevent immune response activation caused by mitochondrial DNA (mtDNA) breakage and release upon replication stalling. We show here that Mirin prevents mitochondrial replication fork breakage in mitochondrial 3’-exonuclease MGME1 deficient cells and the resulting innate immune response induction, but that this occurs independently of MRE11. Furthermore, Mirin also caused alteration of mtDNA supercoiling and accumulation of hemicatenated replication termination intermediates, hallmarks of topoisomerase dysfunction, as well as alleviated topological changes induced by the overexpression of mitochondrial TOP3A, including TOP3A-dependent strand breakage at the non-coding region of mtDNA, potentially explaining its protective effect in the MGME1-knockout cells. Although Mirin does not inhibit TOP3Ain vitro, our results demonstrate its MRE11-independent effects in cells and give insight into the mechanisms of mtDNA segregation, as well as the maintenance of genomic integrity in mitochondria.

Significance Statement

Broken mitochondrial DNA (mtDNA) inMGME1knockout cells activates innate immune response, which is prevented by Mirin, a small molecule inhibitor of MRE11.

Mirin also interferes with mtDNA replication termination and segregation, suggesting that termination intermediates or paused forks are a major source of mtDNA breakage.

We show that these effects are likely dependent on topoisomerase 3A (TOP3A) -related processes in mitochondria, questioning the Mirin target also in the nucleus.
A Toolbox forNeisseria meningitidis: Gene Editing, Complementation and Labelling
Authors: Wuckelt Morgane , Laurent Audrey , Mouville Clémence , Meyer Julie , Jamet Anne , Lecuyer Hervé , Nassif Xavier , Bille Emmanuelle , Pelicic Vladimir , Coureuil Mathieu
Published: March 2024

The efficient transformation ofNeisseria meningitidisandNeisseria gonorrhoeaefacilitates the rapid construction of bacterial mutants with insertion of antibiotic resistance cassettes. However, this strategy limits the construction of strains with multiple mutations. Recent advances in markerless strategies forNeisseriaspecies have enabled the construction of mutants without antibiotic resistance markers. However, these innovative approaches have potential limitations related to the selection strategy or the possible occurrence of spontaneous mutations in the selection marker genes. In addition, complementation tools or labelling strategies forN. meningitidisare also lacking. In this study, we have introduced new tools for markerless mutation, genetic complementation and labelling inN. meningitidis, thus improving the research possibilities for understanding and tackling these pathogens.
Regulation of Versican Expression in Macrophages is Mediated by Canonical Type I Interferon Signaling via ISGF3
Authors: Chang Mary Y. , Chan Christina K. , Brune Jourdan E. , Manicone Anne M. , Bomsztyk Karol , Frevert Charles W. , Altemeier William A.
Published: March 2024

Growing evidence supports a role for versican as an important component of the inflammatory response, with both pro- and anti-inflammatory roles depending on the specific context of the system or disease under investigation. Our goal is to understand the regulation of macrophage-derived versican and the role it plays in innate immunity. In previous work, we showed that LPS triggers a signaling cascade involving TLR4, the Trif adaptor, type I interferons, and the type I interferon receptor, leading to increased versican expression by macrophages. In the present study, we used a combination of chromatin immunoprecipitation, siRNA, chemical inhibitors, and mouse model approaches to investigate the regulatory events downstream of the type I interferon receptor to better define the mechanism controlling versican expression. Results indicate that transcriptional regulation by canonical type I interferon signaling via the heterotrimeric transcription factor, ISGF3, controls versican expression in macrophages exposed to LPS. This pathway is not dependent on MAPK signaling, which has been shown to regulate versican expression in other cell types. The stability of versican mRNA may also contribute to prolonged versican expression in macrophages. These findings strongly support a role for macrophage-derived versican as a type I interferon-stimulated gene and further our understanding of versican’s role in regulating inflammation.
Annealing for prediction of grand canonical crystal structures: Implementation of
n
-body atomic interactions
Authors: Couzinié Yannick , Nishiya Yusuke , Nishi Hirofumi , Kosugi Taichi , Nishimori Hidetoshi , Matsushita Yu-ichiro
Published: March 2024

We propose an annealing scheme usable on modern Ising machines for crystal structures prediction (CSP) by taking into account the general n-body atomic interactions and in particular three-body interactions which are necessary to simulate covalent bonds. The crystal structure is represented by discretizing a unit cell and placing binary variables which express the existence or nonexistence of an atom on every grid point. The resulting quadratic unconstrained binary optimization (QUBO) or higher-order unconstrained binary optimization (HUBO) problems implement the CSP problem and is solved using simulated and quantum annealing. Using the example of Lennard-Jones clusters we show that it is not necessary to include the target atom number in the formulation allowing for simultaneous optimization of both the particle density and the configuration and argue that this is advantageous for use on annealing machines as it reduces the total amount of interactions. We further provide a scheme that allows for reduction of higher-order interaction terms that is inspired by the underlying physics. We show for a covalently bonded monolayer MoS2 crystal that we can simultaneously optimize for the particle density as well as the crystal structure using simulated annealing. We also show that we reproduce ground states of the interatomic potential with high probability that are not represented on the initial discretization of the unit cell.

Published by the American Physical Society
2024
Nuclear magnetic shielding in heliumlike ions
Authors: Yerokhin Vladimir A. , Pachucki Krzysztof , Harman Zoltán , Keitel Christoph H.
Published: March 2024

QED calculations of the nuclear magnetic shielding constant in heliumlike ions are presented. We combine the nonrelativistic QED approach based on an expansion in powers of the fine-structure constant α and the so-called all-order QED approach, which includes all orders in the parameter Zα but uses a perturbation expansion in the parameter 1/Z (where Z is the nuclear charge number). The combination of the two complementary methods makes our treatment applicable to both low-Z and high-Z ions. Our calculations confirm the presence of a rare antiscreening effect for the relativistic shielding correction and demonstrate the importance of the inclusion of the negative-energy part of the Dirac spectrum.

Published by the American Physical Society
2024
Shift of Brewster's angle with two-dimensional materials and structures
Authors: Yermakov Oleh
Published: March 2024

The Brewster effect has a number of applications in antireflection coatings, spectroscopy, and polarization optics, but its tunability is still of high demand. In this Letter, we discover a method of Brewster angle control with two-dimensional conducting layers. Namely, we analyze the angular shift of Brewster's angle depending on the surface conductivity of a two-dimensional layer. First, we derive the analytical model with exact conductivity-dependent solution. Then, we investigate the Brewster angle shift in the cases of monolayer graphene and plasmonic metasurface. Finally, we support our analytical results by the full-wave numerical simulations. The results obtained may find a plethora of applications in flat optical and planar photonic devices.

Published by the American Physical Society
2024
Pressure-dependent phase transitions in hybrid improper ferroelectric Ruddlesden-Popper oxides
Authors: Clarke Gabriel , Daisenberger Dominik , Luo X. , Cheong S. W. , Bristowe Nicholas C. , Senn Mark S.
Published: March 2024

The temperature-dependent phase transitions in Ruddlesden-Popper oxides with perovskite bilayers have been under increased scrutiny in recent years due to the so-called hybrid improper ferroelectricity that some chemical compositions exhibit. However, little is currently understood about the hydrostatic pressure dependence of these phase transitions. Herein we present the results of a combined high-pressure powder synchrotron x-ray diffraction experiment and abinitio study on the bilayered Ruddlesden-Popper phases Ca3Mn2O7 and Ca3Ti2O7. In both compounds we observe a first-order phase transition, that in combination with our density functional theory calculations, we can confidently assign as being between polar A21am and nonpolar Acaa structures. Interestingly, we show that while the application of pressure ultimately favors a nonpolar phase, as is commonly observed for proper ferroelectrics, regions of response exist where pressure actually acts to increase the polar mode amplitudes. The reason for this can be untangled by considering the varied response of octahedral tilts and rotations to hydrostatic pressure and their trilinear coupling with the polar instability.

Published by the American Physical Society
2024
Cross section measurements of neutron elastic and inelastic scattering on
Fe54
Authors: Gkatis G. , Diakaki M. , Noguere G. , Nyman M. , Oprea A. , Paradela C. , Pirovano E. , Plompen A. J. M.
Published: March 2024

Scattering experiments were performed at the Geel Electron Linear Accelerator (GELINA) to determine the differential cross sections of neutron elastic and inelastic scattering on Fe54, using a highly enriched sample. Neutron energies were calculated via the time-of-flight technique. The scattered neutrons were detected using the ELastic and Inelastic Scattering Array (ELISA), a spectrometer consisting of 32 liquid organic scintillators, able to separate neutron and photon induced events via pulse-shape analysis. The detectors are mounted at eight specific angles with respect to the neutron beam direction to allow the concurrent calculation of both the differential and the integral cross section using the Gauss-Legendre quadrature rule. For elastic scattering, angular distributions and integral cross sections were produced in the energy range from 1 to 8 MeV, whereas for inelastic scattering, partial differential and angle integrated cross sections were estimated from the first excited state of Fe54 in the energy range from 2.5 to 5.5 MeV. The results are compared with the available experimental and evaluated nuclear data, as well as with theoretical calculations performed with the TALYS 1.9 and EMPIRE 3.2 codes.

Published by the American Physical Society
2024
Gauge-independent transition separating confinement and Higgs phases in lattice SU(2) gauge theory with a scalar field in the fundamental representation
Authors: Ikeda Ryu , Kato Seikou , Kondo Kei-Ichi , Shibata Akihiro
Published: March 2024

According to the preceding studies, the lattice SU(2) gauge-scalar model with a single scalar field in the fundamental representation of the gauge group has a single confinement-Higgs phase where confinement and Higgs regions are subregions of an analytically continued single phase and there are no thermodynamic phase transitions, which is a well-known consequence of the Osterwalder-Seiler-Fradkin-Shenker theorem. In this paper, we show that we can define new types of gauge-invariant operators by combining the original fundamental scalar field and the so-called color-direction field which is obtained by change of field variables based on the gauge-covariant decomposition of the gauge field due to Cho-Duan-Ge-Shabanov and Faddeev-Niemi. By performing the numerical simulations on the lattice without any gauge fixing, we reproduce the conventional thermodynamic transition line in the weak gauge coupling, and moreover we find a new transition line detected by the new gauge-invariant operators which separates the confinement-Higgs phase into two parts, confinement phase and the Higgs phase, in the strong gauge coupling. All results are obtained in the gauge-independent way, since no gauge fixing has been imposed in the numerical simulations. Moreover, we discuss a physical interpretation for the new transition from the viewpoint of the realization of a global symmetry.

Published by the American Physical Society
2024
Unlocking the surface chemistry of ionic minerals: a high-throughput pipeline for modeling realistic interfaces
Authors: Mates-Torres Eric , Rimola Albert
Published: March 2024

A systematic procedure is introduced for modeling charge-neutral non-polar surfaces of ionic minerals containing polyatomic anions. By integrating distance- and charge-based clustering to identify chemical species within the mineral bulk, our pipeline, PolyCleaver, renders a variety of theoretically viable surface terminations. As a demonstrative example, this approach was applied to forsterite (Mg2SiO4), unveiling a rich interface landscape based on interactions with formaldehyde, a relevant multifaceted molecule, and more particularly in prebiotic chemistry. This high-throughput method, going beyond techniques traditionally applied in the modeling of minerals, offers new insights into the potential catalytic properties of diverse surfaces, enabling a broader exploration of synthetic pathways in complex mineral systems.
Fuel consumption estimation for jet aircraft: a mathematical model development
Authors: Benkhaled Amar , Benkhedda Amina , Benaouda Zouaoui Braham , Ribouh Soheyb
Published: March 2024

Purpose

Reducing aircraft fuel consumption has become a paramount research area, focusing on optimizing operational parameters like speed and altitude during the cruise phase. However, the existing methods for fuel reduction often rely on complex experimental calculations and data extraction from embedded systems, making practical implementation challenging. To address this, this study aims to devise a simple and accessible approach using available information.

Design/methodology/approach

In this paper, a novel analytic method to estimate and optimize fuel consumption for aircraft equipped with jet engines is proposed, with a particular emphasis on speed and altitude parameters. The dynamic variations in weight caused by fuel consumption during flight are also accounted for. The derived fuel consumption equation was rigorously validated by applying it to the Boeing 737–700 and comparing the results against the fuel consumption reference tables provided in the Boeing manual. Remarkably, the equation yielded closely aligned outcomes across various altitudes studied. In the second part of this paper, a pioneering approach is introduced by leveraging the particle swarm optimization algorithm (PSO). This novel application of PSO allows us to explore the equation’s potential in finding the optimal altitude and speed for an actual flight from Algiers to Brussels.

Findings

The results demonstrate that using the main findings of this study, including the innovative equation and the application of PSO, significantly simplifies and expedites the process of determining the ideal parameters, showcasing the practical applicability of the approach.

Research limitations/implications

The suggested methodology stands out for its simplicity and practicality, particularly when compared to alternative approaches, owing to the ready availability of data for utilization. Nevertheless, its applicability is limited in scenarios where zero wind effects are a prevailing factor.

Originality/value

The research opens up new possibilities for fuel-efficient aviation, with a particular focus on the development of a unique fuel consumption equation and the pioneering use of the PSO algorithm for optimizing flight parameters. This study’s accessible approach can pave the way for more environmentally conscious and economical flight operations.
Inverting the paradigm: digital transformation’s impact on firm performance and the counterintuitive role of gender
Authors: Shehadeh Maha , Alshurafat Hashem , Arabiat Omar
Published: March 2024

Purpose

This study aims to analyze the impact of digital transformation on firm performance within the banking sector, specifically focusing on the Amman Stock Exchange (ASE)-listed banks from 2015 to 2022. Additionally, it explores the influence of gender dynamics on the implementation and outcomes of these digital transformation initiatives.

Design/methodology/approach

The study adopts a robust empirical approach, using manual content analysis of annual reports from ASE-listed banks. The Digital Transformation Disclosure Index (DTDI) is used to assess the extent and nature of digital transformation initiatives within these banks. The methodology is designed to provide a comprehensive evaluation of the correlation between digital transformation efforts, firm performance and gender dynamics.

Findings

The research reveals that digital transformation initiatives have a significant positive impact on the performance of ASE-listed banks. It also uncovers nuanced insights into the role of gender dynamics, indicating that gender diversity within firms influences the adoption and success of digital transformation strategies in complex ways.

Research limitations/implications

The findings of this study contribute to the understanding of digital transformation in the banking sector, offering empirical evidence on its benefits for firm performance. Additionally, the study illuminates the intricate role of gender dynamics in digital transformation, providing a new perspective on organizational diversity within the context of technological change.

Originality/value

This research pioneers in academically linking digital transformation and gender dynamics within the banking sector, addressing a notable gap and introducing a fresh academic perspective. Practically, it equips banking executives and policymakers with actionable insights for gender-inclusive digital strategies, crucial for enhanced firm performance. Methodologically, the study sets a benchmark in research innovation, using the DTDI to offer a replicable model for future investigations in this evolving field.
Does political skill promote knowledge hiding? An impression management perspective
Authors: Chen Lifan , Zhang Shanshan , Hu Xiaoli , Liu Shengming , Lan Rujia
Published: March 2024

Purpose

As a counterproductive interpersonal work behavior, knowledge hiding inhibits team creativity, hampers collaboration and ultimately has a detrimental impact on organizational performance. Drawing upon the impression management perspective. This study aims to investigate how and when employees’ political skill affects their knowledge-hiding behavior in real work contexts.

Design/methodology/approach

The authors tested the hypotheses using data gathered from 266 employees in China using a time-lagged research design.

Findings

The results indicate that political skill positively influences knowledge hiding through the supplication strategy. Moreover, the positive effect of political skill on this strategy is stronger under higher levels of competition.

Research limitations/implications

A cross-sectional design and the use of self-report questionnaires are the limitations of this study.

Originality/value

The authors contribute to the literature on the emergence of knowledge hiding by identifying an impression management perspective. The authors also contribute to the literature on political skill by exploring the potential negative effects of political skill in the interpersonal interaction. Moreover, the authors enrich the understanding of the literature in competitive climate by introducing the impression management theory and exploring its influence on knowledge floating.
Relations of subordination: Canada’s first indigenous dean of a law school
Authors: Grant James D.
Published: March 2024

Purpose

The goal was emancipatory, to characterise and dislodge oppressive management practices, to allow for the possibility of seeking an alternative organisational construction free of postcolonial/subaltern subordination and discrimination in a local, well-documented narrative.

Design/methodology/approach

The study was informed by a postcolonial/subaltern perspective and drew on the employment experience of an Aboriginal woman, Canada’s first Indigenous Dean of a law school. The researcher employed a combination of case study and critical discourse analysis with the aim of advancing rich analyses of the complex workings of power and privilege in sustaining Western, postcolonial relations.

Findings

The study made several conclusions: first, that the institution, a medium-sized Canadian university, carefully controlled the Indigenous subaltern to remake her to be palatable to Western sensibilities. Second, the effect of this control was to assimilate her, to subordinate her Indigeneity and to civilise in a manner analogous to the purpose of Indian residential schools. Third, that rather than management’s action being rational and neutral, focused on goal attainment, efficiency and effectiveness, it was an implicit moral judgement based on her race and an opportunity to exploit her value as a means for the university’s growth and status.

Originality/value

Through a postcolonial/subaltern perspective, this study demonstrated how management practices reproduced barriers to the participation of an Indigenous woman and the First Nations community that an organisation was intended to serve. The study demonstrated how a Western perspective – that of a university’s administration, faculty and staff – was privileged, or taken for granted, and the Indigenous perspective subordinated, as the university remained committed to the dispossession of Indigenous knowledge and values.
The role of microbiota on rheumatoid arthritis onset
Authors: Juárez‐Chairez Milagros Faridy , Cid‐Gallegos María Stephanie , Jiménez‐Martínez Cristian , Prieto‐Contreras Luis Fernando , Bollain‐y‐Goytia de‐la‐Rosa Juan José
Published: March 2024

Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes inflammation and pain, which can lead to the loss of normal joint function. Although the exact cause of the disease is not yet fully understood, both environmental factors and genetics may play a role in its development. Moreover, research suggests microbiota contributes to the onset and progression of RA. People with RA show higher quantities of bacteria such as Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella copri, Proteus mirabilis, and Lactobacillus salivarius compared to healthy individuals. Conversely, studies propose that Lactobacillus casei, a probiotic bacterium with immunomodulatory properties, has beneficial effects for RA in murine and human models. Therefore, this work reviews the potential role of the gut microbiota in the development of RA and explores the feasibility of using probiotic bacteria as a supplementary treatment for this disease.
Lung transplant airway complications treated with biodegradable airway stents: The Dutch multi‐center experience
Authors: van Pel Roel , Gan Tji , Daniels Johannes M. A. , Ruigrok Dieuwertje , Hellemons Merel E. , Klooster Karin , Slebos Dirk‐Jan
Published: March 2024

Introduction

Treatment of post lung‐transplant airway complications is challenging, and treatment with conventional airway stents is associated with adverse events. More recently, biodegradable airway stents (BDS) have been introduced and may be used to reduce these adverse events. In this study we explore the feasibility of treatment with BDS post lung transplant.

Methods

All patients treated with BDS in The Netherlands were included in this retrospective multicenter study. Feasibility, life span of the stent, occurrence of adverse events, and evolution of lung function were evaluated.

Results

Twelve patients (six malacia and six stenosis) received a total of 57 BDS, ranging from 1 to 10 BDS per patient. Six patients had been pretreated with conventional airway stents. Median stent life span was 112 days (range 66–202). No adverse events occurred during stent placement. In 5 out of 57 stent placements, a single additional bronchoscopy was necessary because of mucus accumulation (n = 4) or excessive granulation tissue (n = 1). All stent naïve patients became airway stent independent after treatment; all patients pretreated with conventional airway stents were still airway stent dependent at the end of follow up.

Conclusion

Treatment with BDS is safe and feasible. Adverse events were mild and easily treatable. All patients with initial treatment with BDS were airway stent independent at the end of follow up with a median treatment of 4 BDS.
Early ablation of newly diagnosed paroxysmal atrial fibrillation (NEWPaAF) versus newly diagnosed persistent atrial fibrillation (NEWPeAF): Comparison of patient populations and ablation outcomes
Authors: Winkle Roger A. , Hardwin Mead R. , Engel Gregory , Salcedo Jonathan , Brodt Chad , Barberini Patricia , Lebsack Cynthia , Kong Melissa H. , Kalantarian Shadi , Patrawala Rob A.
Published: March 2024

Introduction

Little is known about very early atrial fibrillation (AF) ablation after first AF detection.

Methods

We evaluated patients with AF ablation <4 months from newly diagnosed paroxysmal AF (NEWPaAF) and newly diagnosed persistent AF (NEWPeAF). We compared the two patient populations and compared ablation outcomes to those undergoing later ablation.

Results

Ablation was done <4 months from AF diagnosis in 353 patients (135 = paroxysmal, 218 = persistent). Early ablation outcome was best for NEWPaAF versus NEWPeAF for initial (p = 0.030) but not final (p = 0.102) ablation. Despite recent AF diagnosis in both groups, they were clinically quite different. NEWPaAF patients were younger (64.3 ± 13.0 vs. 67.3 ± 10.9, p = 0.0020), failed fewer drugs (0.39 vs. 0.60, p = 0.007), had smaller LA size (4.12 ± 0.58 vs. 4.48 ± 0.59 cm, p < 0.0001), lower BMI (28.8 ± 5.0 vs. 30.3 ± 6.0, p = 0.016), and less CAD (3.7% vs. 11.5%, p = 0.007), cardiomyopathies (2.2% vs. 22.9%, p = 0.0001), hypertension (46.7% vs. 67.4%, p < 0.0001), diabetes (8.1% vs. 17.4%, p = 0.011) and sleep apnea (20.0% vs. 30.3%, p = 0.031). For NEWPaAF, early ablation AF‐free outcome was no better than later ablation (p = 0.314). For NEWPeAF, AF‐free outcomes were better for early ablation than later ablation (p < 0.0001). Delaying ablation allowed more strokes/TIAs in both AF types (paroxysmal p = 0.014, persistent p < 0.0001).

Conclusions

Patients presenting for early ablation after newly diagnosed persistent AF have more pre‐existing comorbidities and worse initial ablation outcomes than patients with NEWPaAF. For NEWPaAF, there was no advantage to early ablation, as long as the AF remained paroxysmal. For NEWPeAF, early ablation gave better outcomes than later ablation and they should undergo early ablation. For both AF types, waiting was associated with more neurologic events, suggesting all patients should consider earlier ablation.
A multi‐centre randomized controlled trial comparing connective tissue graft with collagen matrix to increase soft tissue thickness at the buccal aspect of single implants: 3‐Year results
Authors: Surdiacourt Lenz , Christiaens Véronique , De Bruyckere Thomas , De Buyser Stefanie , Eghbali Aryan , Vervaeke Stijn , Younes Faris , Cosyn Jan
Published: March 2024

Aim

To compare connective tissue graft (CTG) with collagen matrix (CMX) in terms of increase in buccal soft tissue profile (BSP) when applied at single implant sites.

Materials and Methods

Patients with a single tooth gap in the anterior maxilla and horizontal mucosa defect were enrolled in a multi‐centre randomized controlled trial. All were fully healed sites with a bucco‐palatal bone dimension of at least 6 mm, and received an immediately restored single implant using a full digital workflow. Patients were randomly allocated to the control (CTG) or test group (CMX: Geistlich Fibro‐Gide, Geistlich Pharma AG, Wolhusen, Switzerland) to increase buccal soft tissue thickness. Primary endpoints were increase in BSP at T1 (immediately postop), T2 (3 months), T3 (1 year) and T4 (3 years) based on superimposed digital surface models. Secondary endpoints included patient‐reported, clinical and aesthetic outcomes.

Results

Thirty patients were included per group (control group: 15 males, 15 females, mean age 50.1 years; test group: 14 males, 16 females, mean age 48.2 years) and 50 could be re‐examined at T4. The changes in BSP over time were significantly different between the groups (p < .001). At T4, the estimated mean increase in BSP amounted to 0.83 mm (95% confidence interval [CI]: 0.58–1.08) in the control group and 0.48 mm (95% CI: 0.22–0.73) in the test group. The estimated mean difference of 0.35 mm (95% CI: 0.06–0.65) in favour of the control group was significant (p = .021). No significant differences between the groups could be observed in terms of patients' aesthetic satisfaction (p = .563), probing depth (p = .286), plaque (p = .676), bleeding on probing (p = .732), midfacial recession (p = .667), Pink Esthetic Score (p = .366) and Mucosal Scarring Index (p = .438). However, CMX resulted in significantly more marginal bone loss (−0.43 mm; 95% CI: −0.77 to −0.09; p = .015) than CTG.

Conclusions

CTG was more effective in increasing buccal soft tissue profile and resulted in less marginal bone loss than CMX. Therefore, CTG remains the gold standard to increase soft tissue thickness at implant sites. Clinical Trial registration: This study was registered in ClinicalTrials.gov (NCT04210596).
Altered hippocampal doublecortin expression in Parkinson's disease
Authors: Plácido Evelini , Koss David J. , Outeiro Tiago Fleming , Brocardo Patricia S.
Published: March 2024

Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by motor and non‐motor symptoms. Motor symptoms include bradykinesia, resting tremors, muscular rigidity, and postural instability, while non‐motor symptoms include cognitive impairments, mood disturbances, sleep disturbances, autonomic dysfunction, and sensory abnormalities. Some of these symptoms may be influenced by the proper hippocampus functioning, including adult neurogenesis. Doublecortin (DCX) is a microtubule‐associated protein that plays a pivotal role in the development and differentiation of migrating neurons. This study utilized postmortem human brain tissue of PD and age‐matched control individuals to investigate DCX expression in the context of adult hippocampal neurogenesis. Our findings demonstrate a significant reduction in the number of DCX‐expressing cells within the subgranular zone (SGZ), as well as a decrease in the nuclear area of these DCX‐positive cells in postmortem brain tissue obtained from PD cases, suggesting an impairment in the adult hippocampal neurogenesis. Additionally, we found that the nuclear area of DCX‐positive cells correlates with pH levels. In summary, we provide evidence supporting that the process of hippocampal adult neurogenesis is likely to be compromised in PD patients before cognitive dysfunction, shedding light on potential mechanisms contributing to the neuropsychiatric symptoms observed in affected individuals. Understanding these mechanisms may offer novel insights into the pathophysiology of PD and possible therapeutic avenues.

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